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Auteur(s) : Z. M'hamed
Mots-clés : Dépense publique ; Performance macroéconomique ; Croissance économique ; Modèle VAR
ISSN : 1112-6132 | E-ISSN : 2588-1930 | Vol : 18, N° : 30, pp : 639-656
Résumé : L’objectif de ce papier est de déterminer l’impact de dépenses publiques sur les performances
macroéconomiques en Algérie en tenant compte des rythmes de croissance. Utilisant des données
annuelles couvrant la période (1992-2019), les régressions du modèle VAR révèlent une relation
positive entre les fondamentaux économiques et la dimension de l’intervention gouvernementale
déployée par de plans de relance budgétaire adoptée depuis l’année 2001. Ce résultat peut sans
doute s’expliquer par le rôle de régulateur et de stabilisateur de l’activité économique globale joué
par l’Etat sur la scène nationale surtout lorsque se profilent de sérieuses menaces de déséquilibres
conjoncturels. Compte tenu de ces spécificités de l’économie algérienne, il est probable que ces résultats ne soient pas généralisables, et, que ces tests investis ne permettent pas de mettre en lumière une causalité significative entre dépenses publiques et croissance économique.
Auteur(s) : Assia Hebri.
Mots-clés : ظام النقل المستدام قياس الآداء ; الخطة الكندية للنقل المستدام
E-ISSN : EISSN: 2716-8301 | Vol : 16, N° : 03, pp : 420-440
Résumé : Transportation system and services are central factors in achieving progress,development and change, as they are indicative of the level of economic, social and environmental development of countries, as these systems involve a wide range of problems that come directly related to current transportation systems, such as polluting emissions, noise, traffic accidents and exhaustion. Resources and difficulty in accessing the luxury causes. Transportation is essential for large-scale development and has a profound personal impact on the lives of individuals.The following study,which was conducted on the Canadian Ministerial Program of Action for the period (2019-2020),by analyzing the tables of measurement indicators used in the field of sustainable transport, emphasizes the strategic importance of measuring the performance of the transportation system and the importance of indicators in forecasting and estimating the future directions of sustainability in Canadian transport for the coming period.
Auteur(s) : Djilali BOUHA, Habib KHELLAFI, El Bahri OULD CHIKH, Hadj Miloud MEDDAH , Abdellah KAOU
Mots-clés : Friction stir welding (FSW); Polymer HDPE; Welding tool; Microhardness; Tool geometries; Bobbin tool FSW
ISSN : 663-4144 | Vol : 61, pp : 95-114
Résumé : Welding polymers by the friction stir welding (FSW) technique is one assembly process
among several known assembly techniques which consists in welding two materials without filler
material. FSW process is based on the generation of heat due to friction and material
deformation under an axial force. Among the main aspects affecting material flow, the choice of
welding tool geometry has become of great interest to improve the welds quality. The main
objective of this unique work is to weld polymers using one of the FSW techniques. A new method
of welding HDPE (high density polyethylene) plates, called BT-FSW (bobbin tool friction stir
welding) was developed. Standard rectangular shape intended for the distribution of natural gas
has been successfully welded by BT-FSW. Tensile tests and hardness measurements were carried
out on samples cut from the welded sheets and the results were analyzed to compare the mechanical
characteristics of the plates welded by the BT-FSW and conventional FSW (C-FSW) processes. The
results of the comparative studies on the micro-hardness characteristics and mechanical properties
of the two welding processes indicate that welding using the bobbin tool can significantly reduce
hardness and improve both weld formation and mechanical properties of joints. This study showed
that the design of the welding tool has a big impact on the weld strength. An improvement in the
mechanical properties of the specimens welded by BT-FSW was observed to give a better welding
quality for the polymers studied.
Auteur(s) : لقام عبد الكريم بوجلال و بوزنورة أسماء
Mots-clés : الطاقة الأحفورية ; الاقتصاد الأخضر ; التهديدات والتحديات
E-ISSN : 2716-8379 | Vol : 10, N° : 01, pp : 59-78
Résumé : الإكراهات البيئية من تدهور التربة، تغير المناخ وتعدد أشكال التلوث، إضافة إلى التهديدات التي يعاني منها الاقتصاد من خطر النضوب والأزمات الاقتصادية لاعتماده على الطاقات الأحفورية، كلها رهانات رئيسية تواجهها الجزائر وتفرض إعادة توجيه النموذج الاقتصادي نحو اقتصاد أخضر. وهذا ما عمدت إليه الجزائر منذ اثنى عشر سنة خاصة في مجالي الطاقة الشمسية وطاقة الرياح، إلا أنها لاتزال في بدايتها مع مواجهتها لتحديات عدة. فاستغلال الطاقات المتجددة في الجزائر يظل ضعيف جدا لم يتعد 0.5℅ من الاستهلاك الكلي وإنتاج الوقود الحيوي يبقى منعدما أما إنتاج الكهرباء انطلاقا من الموارد الطبيعية المتجددة يظل هو الآخر محدودا، مع استمرار الاعتماد الكبير على موارد الطاقة الأحفورية. نظرا للتكلفة المرتفعة لبرنامج التوجه نحو الطاقات المتجددة.
Auteur(s) : Z. M'hamed ; M. Dahou
Mots-clés : Taux de change ; dévaluation, ; balance commerciale ; Mundell-Fleming
ISSN : 2352-9962 | E-ISSN : 2572-0147 | Vol : 8, N° : 3, pp : 995-1016
Résumé : Ce papier tente d’analyser et d’évaluer l'effet de la politique de dévaluation du dinar, par l’utilisation du modèle de Mundell-Fleming, sur l’économie nationale algérienne. L’approche adoptée met en avant les interactions des principaux variables macroéconomiques afin d'incorporer au mieux l'effet de resserrement monétaire poursuivi souvent en période de mauvaise conjoncture économique. Pour réaliser notre objectif, nous commençons par rappeler les principaux caractères du modèle, puis met en perspective la trajectoire de l’économie algérienne au cours des dernières décennies. Il apparait enfin que cette dévaluation restrictive, dans la phase actuelle, ne présentait aucune efficacité économique.
Auteur(s) : Assia Hebri.
Mots-clés : الإستراتيجية البيئية،الأداء البيئي،التنمية المستدامة،المؤشرات ،كندا. ; Key words: environmental strategy, environmental performance, sustainable development, indicators, Canada
E-ISSN : EISSN: 2600-6693 | Vol : Volume 12, , N° : Numéro 1,, pp : Pages 29-48
Résumé : تهدف هذه الدراسة إلى إبراز الدور الإستراتيجي لعملية قياس الأداء البيئي للإستراتيجيات البيئية الوطنية وأثره المباشر على ميكانيزمات تطويرها محليا و دوليا. أثبتت الدراسة التالية،من خلال تحليل المؤشرات البيئية الكندية الواردة في مشروع الإستراتيجية المعلن عنه في 2016،وخطط العمل التي تبين أولويات الاستدامة في كندا في الفترة المدروسة ما بين(2016-2019)،الأهمية الإستراتيجية للارتباطات النظرية والتطبيقية القائمة بين التطوير الإستراتيجي للأداء البيئي و عملية القياس العلمية للتحقيقات المنجزة لحساب البيئة الكندية. Abstract: This study aims to highlight the strategic role of the process of measuring the environmental performance of national environmental strategies and its direct impact on the mechanisms of their development locally and internationally, The Canadian Environmental Strategy for the period (2016-2019), shows the importance of the theoretical and practical links that exist between the strategic development of environmental performance and the scientific measurement process of environmental indicators contained in the draft strategy announced in 2016.
Auteur(s) : Habib Bouzir, Gherici Beldjilali and Benaoumeur Bayour
Mots-clés : Almost contact metric structure, C12-manifolds, CR-manifolds.
Vol : N18, 2021, N° : 239 , pp : 1-13
Auteur(s) : Habib Bouzir, Gherici Beldjilali and Benaoumeur Bayour
Mots-clés : Almost contact metric structure, C12-manifolds, CR-manifolds.
Vol : N18, 2021, N° : 239 , pp : 1-13
Résumé : In this article, we study some properties of three dimensional
C12-manifolds and we give a method of construction for normal manifold
starting from a non-normal but integrable manifold. Concrete examples
are given.
Auteur(s) : Emad Kamil.Hussein, Tayser Sumer. Gaaz, Kussay Ahmed. Subhi, Samir. Ghouali, Mohammed Seghir. Guellil
E-ISSN : 2321-2543 | Vol : 9, N° : 3, pp : 01-14
Résumé :
Purpose: As a result of a sudden spreading of an epidemic novel virus, scientifically named COVID-19, this paper has been done to present a contribution towards fighting this virus in Iraq.
Methodology: This investigation is focusing on constructing an engineering mathematical model based on the Suspected, Infected, and Recovered model (SIR), given by Kermack and McKendrick.
Main Findings: Iraqi people are facing and suffering from this COVID-19. Three governorates occupying the locally highest infection levels, plus the world's highest deaths to infected cases ratio of about 11%, are Baghdad, Sulaimani, and Karbala.
Implications: It is showed that the Reproduction ratio R0)K is positive (greater than 1) in the three nominated zones, which means that the epidemic disease will keep spreading in a broad manner and depending on many specific factors. Many effective recommendations are presented to avoid spreading this novel virus via many techniques.
Novelty: SIR model is used to assess epidemic levels in 3 zones.
Auteur(s) : H.Assia,D.khaoula- Z.Hayet
Mots-clés : المناخ التنظيمي , ضغوط العمل ، الاتصال الفعال ، إدارة الضغوط الوظيفية ، الموارد البشرية .
E-ISSN : 2602-6058 | Vol : Volume 9, , N° : Numéro 1, pp : , Pages 74-101
Résumé : يشير المناخ التنظيمي إلى التفاعل بين خصائص الفرد المرتبطة إلى حد كبير بالنظام المعرفي والخبرات والتجارب والتعليم والثقافة و بيئة العمل التي تميز المنظمة عن غيرها من المنظمات وتختلف من منظمة إلى أخرى باختلاف الأبعاد التي تحدد المناخ التنظيمي من هيكل تنظيمي ، مركزية القرار،اتصالات،أنظمة أجورو حوافز،نمط القيادة،التكنولوجيا. أكدت الدراسة التالية وجود ارتباطات ذات دلالة إحصائية إيجابية مهمة ومتفاوتة التأثير بين ضغوط العمل والعوامل السابقة ، في إطار مناخ تنظيمي ملائم يعمل كوسيط ناجع بين متطلبات الوظيفة والحاجات المهنية للأفراد.
Auteur(s) : Hebri Assia
Mots-clés : إدارة النفايات؛شراكة هولندية- جزائرية؛تحليل إستراتيجي؛SWOT؛الجزائر. Key Word: Waste management, Dutch-Algerian partnership, Strategic analysis SWOT, Algeria
E-ISSN : 2600-6731 | Vol : Volume 24, N, N° : Numéro 1,, pp : Pages 589-608
Résumé : تهدف الدراسة التالية إلى التحليل الإستراتيجي للفرص الاستثمارية للشركات الهولندية والشركات الأخرى فيما يتعلق بأنظمة تسيير النفايات في الجزائر على أساس وجود فرص كثيرة و متعددة التخصصات.أثبتت الدراسة بواسطة التحليل الإستراتيجي الرباعيSWOT للدراسة الإستراتيجية المعدة من طرف الوكالة الهولندية للأعمال2018،وجود إمكانيات عديدة للشريك الهولندي في مجال التجميع،التسليم،البناء والتطوير التكنولوجي ،زيادة معدلات التدوير الإستغلال الإقتصادي للنفايات،الخدمات الإستشارية و خلق القيمة،بإستخدام الشراكات المحلية ودراسات السوق المتخصصة في مجال تسيير النفايات. Abstract: The following study aims at strategic analysis of investment opportunities for Dutch companies and other companies with regard to waste management systems in Algeria, on the basis of the presence of many opportunities and multidisciplinary, by partnership with Algerian companies working in the field studied. The study was proven by the strategic SWOT contained in the strategic study prepared by Dutch Business Agency 2018, many possibilities exist for the Dutch partner in the field of assembly delivery, construction, technology development, increased recycling rates, economic exploitation of waste and value creation, using partnerships For local market studies specialized in the field of waste management
Auteur(s) : بن زكورة العونية
Mots-clés : جائحة كورونا، البيئة، التلوث البيئي، التدهور البيئي،التكنولوجيا النظيفة،
ISSN : 1572-2676 | E-ISSN : 1572-2676 | Vol : 6, N° : 5, pp : 187-206
Résumé : ملخص: تهدف هذه الدراسة للتعرف على تداعيات جائحة كورونا على البيئة، حيث أثر انتشار فيروس كوفيد 19 بشكل سلبي على العديد من القطاعات الاقتصادية العالمية، كما كان له بعض التأثيرات الايجابية على قطاعات أخرى كقطاع الانترنت والتجارة الالكترونية، الخدمات اللوجستية، البرمجيات وكذا قطاع البيئة. باعتبار البيئة من العناصر الأكثر تضررا من تطور نشاط الإنسان، فقد جاءت الجائحة لتحد من هذا النشاط وتسمح للبيئة باسترجاع عافيتها. كما أن هذه الأزمة أكدت على ضرورة الاعتماد على التكنولوجيا النظيفة كآلية لحماية البيئة من التدهور، حيث تعبر هذه الأخيرة على مجموع الاستراتيجيات المتبعة للتعامل مع مصدر المشكلة والوقاية من التلوث وبالتالي تحقيق التنمية المستدامة.
Auteur(s) : Mohammed Anis. Oukebdane, Samir. Ghouali, Emad Kamil. Hussein, Mohammed Seghir. Guellil, Amina Elbatoul. Dinar, Walid. Cherifi, Abd EllahYoucef. Taib, Boualem. Merabet
Résumé : The severe damage caused by COVID-19 has become a reality, and there is no longer a way to save humanity from this epidemic except diagnose and prevention, especially with emergence delay and lack of vaccine recognized by the World Health Organization. Without therapeutic treatment or explicit restorative immunizations for COVID-19, it is fundamental to diagnose the disease at an early stage and quickly seclude patients contaminated with the virus. This study aims at estimating the damage via consistency of chest imaging, which is not always feasible or possible. Here, an application is proposed to solve the problem via a WEB Predictor ‘COVIDz” and a program exploiting deep learning, so as emergency care will be able to systematically bring chest X-ray images and predict the percentage of the absence or presence of COVID-19. The proposed approach (custom VGG model) and our WEB site “COVIDz” objective validation of the suggested solution obtained the best classification efficiency of 99.64%, F-score of 99.2%, precision of 99.28%, MCC of 99.28%, recall of 99.28%, and a specificity value of 100%.
Auteur(s) : Assia Hebri.
Mots-clés : لتنوع البيولوجي،الخطط القطاعية،الإستراتيجية الجزائرية،الإستدامة،الجزائر. ; Keywords:Biodiversity, Sectoral Plans,Algerian Strategy,sustainability,Algeria
E-ISSN : 2600-6839 | Vol : Volume 11,, N° : Numéro 3, pp : , Pages 349-366
Résumé : تقوم الدراسة التالية على إبراز ضرورة إدماج الاستدامة في إعداد السياسات العامة التي تظهر جليا في الخطط الفصلية والسنوية لجميع القطاعات ضمن الإستراتيجية الجزائرية للتنوع البيولوجي(2016-2030). تحقيقا لأهداف أيشي للتنوع البيولوجي في مشروع الإستراتيجية المقترح للفترة المدروسة ،تؤكد الدراسة على ضرورة حوكمة التنفيذ القائم على التنسيق والتكامل بين جميع الفاعلين بالدولة لضمان التحسين المستمر. Abstract: The following study highlights the need to integrate sustainability into the development of public policies that are evident in the quarterly and annual plans for all sectors within the Algerian Biodiversity Strategy (2016-2030). To achieve Aichi's objectives in the strategy project ,the study emphasizes the need for governance of implementation based on coordination and integration among all actors in the country to ensure continuous improvement
Auteur(s) : Mohamed A MEDEBBER1, Belkacem OULD SAID2, Noureddine Retiel
Mots-clés : Natural Convection; Surface Radiation; Finite Volume Method; Coaxial Conical Cavity
ISSN : 1662-9507 | Vol : 408, pp : pp 19-32
Résumé : The present study investigates the combined free convection and surface radiation in a
conical annular cylinder filled with air (Pr=0.71). The steady-state continuity, Navier–Stokes and
energy equations were carried out by the finite volume method, and the Discrete Ordinates Method
(DOM) was used to solve the radiative heat transfer equation (RTE). The boundary conditions are
such that the inner and the outer radius of cone are maintained at hot (Th) and cold (Tc) isothermal
temperature. The horizontal upper and lower walls are assumed to be isolated. Concerning the
radiation exchange, we consider that the fluid (air) is transparent, so only the solid surfaces
contribute to the radiation exchange and assumed to be diffuse-gray. The computations are
performed for Rayleigh number (Ra) in the range 103≤Ra≤106, the surface emissivity (ε) 0≤ε≤1 and
the cone angle (????????) 63º, 76º, 80º and 84º. The key parameters for this analysis are considered as
Rayleigh number (Ra), surface emissivity (ε) and the cone angle (????????). Results are presented in terms
of isotherms, streamlines and the average Nusselt numbers.
ISSN : 2180-1843 | E-ISSN : 2289-8131 | Vol : 13, N° : 1,
Résumé : Nowadays, computer equipment has hardware or software clocks to which they refer to time stamp files, transactions and emails. The design of a quartz oscillator, such as clocks drift functions like ordinary watches that do not perfectly match. Therefore, it needs networked machines sharing common resources. For instance, UNIX makes command updates key files ensuring that files on which it depends exist and are up-to-date. Also, correlating log messages from several systems becomes very difficult if it does not occur at the same time. This paper focuses mainly on how to detect attacks, trying to predict attacks based on delays caused by this equipment. A server is configured using NTP protocol whose main target is to be implemented in UNIX system, to see how the NTP server is managed with the powerful package Chrony for Ubuntu. The examined results via Python reveal that clients neither will be nor able to make final decisions just after negotiating with servers in several attempts, before or after accepting their clock.
Auteur(s) : Mohammed Anis. Oukebdane, Samir. Ghouali, Emad Kamil. Hussein, Mohammed Seghir. Guellil, Amina Elbatoul. Dinar, Walid. Cherifi, Abd EllahYoucef. Taib, Boualem. Merabet
Vol : 6, N° : 5,
Résumé : Nowadays, electrical grids are using information and communication technologies for providing intelligence in electrical grids, since alternative energy sources are increasing to meet the world’s energy consumption demand. Interest in Internet of Things (IoT) is lastingly growing and may involve more data-sensitive projects when applied in smart micro-grids (SMGs), and security is a priority to be ensured for power distribution and consumption. Moreover, standards for IoT platforms should be optimized for monitoring such consumption and controlling grid resources, which present more demanding challenges. In such context, this work aims to adopt an appropriate PV-based energy generation system feeding a remote telecom network (RTN), via evaluating its performance, and monitor a related smart micro-grid (SMG) to offer a secure and energy-efficient management for RTNs. Simulink simulations have proved DC/DC converters as the best choice for future telecoms applications by using PV systems. Boost converters reveal to be suitable for PV systems while optimizing a fewer transformers electric energy conversion. A focus is also on how to detect and counteract attacks to prevent power theft/loss while feeding RTNs, showing that the best security choice is the use of Snort to prevent from inside net LAN, and ASA firewall to obstruct attacks from outside.
Auteur(s) : Dr LEKKAM Abdelkrim Boudjelal
Mots-clés : Taux de change, Monnaie, Régime de change, Marché des changes, Politique de change
ISSN : 1012-0009 | E-ISSN : 2437-0568 | Vol : 37, N° : 01, pp : 41-71
Résumé : L'Algérie est face à un environnement économique envisageant des changements significatifs, à l’intérieur du pays comme à l’extérieur. Beaucoup de ces changements ont d’importantes implications pour le choix du régime de change et sont probablement en train de rendre la défense de tout type d’ancrage difficile. Un régime de change autour d’un panier et admettant un degré de flexibilité à la monnaie nationale, en accord avec Williamson (1998, 2000), Dornbush et Park (1999) et Goldstein (2000), nous semble convenir le mieux. Il a la possibilité de se décliner sous différentes formes selon la situation du pays et les objectifs à atteindre. Il ressort donc de ce papier est que la politique de change en Algérie reste toujours restrictive, même si on parle d’un marché des changes pseudo-libéral à travers les mécanismes du marché interbancaire de change.
Auteur(s) : Fethi Mohammed Bekkara,Youcef Benmimoun, Amel Kheiter, Amine Chelih, AmarTilmatine
Mots-clés : Air filtersCorona chargingPotential decayGround electrodeFiltration efficiency
Vol : 110, N° : 103554,
Auteur(s) : MA Bekhti, MS Belardja, M Lafjah, F Chouli, A Benyoucef
ISSN : 1548-0569 | Vol : 42, N° : 1, pp : 127-133
Résumé : Des matériaux hybrides à base d'Al 2 O 3 , modifiés avec de la polyaniline ont été obtenus. Des échantillons ont été synthétisés par polymérisation chimique de monomère d'aniline avec des nanoparticules d'Al 2 O 3 , le persulfate d'ammonium a été utilisé comme oxydant. Les échantillons résultants ont été entièrement caractérisés par spectroscopie photoélectronique aux rayons X (XPS), diffraction des rayons X (XRD), spectromètre infrarouge à transformée de Fourier (FTIR), microscopie électronique à balayage (SEM) et spectroscopies UV-vis, qui ont montré que les polymérisations ont été réalisées. Il est important de noter que ce travail représente un moyen efficace de définir les propriétés optiques des nanocomposites synthétisés, obtenus en ajustant les quantités d'Al 2 O 3pendant la polymérisation,
Auteur(s) : Leila Mouacher, Ahmed Yahiaoui, Aicha Hachemaoui, Abdelkader Dehbi, Ali Mustapha Benkouider
Mots-clés : Organoclay,conjugated polymer, nanocomposites, structural, thermal, and electrical properties
ISSN : 0303-402X | E-ISSN : 1435-1536 | Vol : 299, N° : 05, pp : 763–772
Résumé : A detailed study about the chemical oxidative polymerization of aniline with/or 2-aminothiazole in the presence of an organoclay has been reported. The first step achieved was the organophilization of the clay by using cetrimonium bromide (CTAB) surfactant; then, the nanocomposites were synthesized with the addition of a stoichiometric amount of ammonium persulfate (APS) in aqueous solution. The effect of varying the reaction time and oxidant/monomer and co-monomer molar ratio on the polymer yield was investigated. The resulting nanocomposites were fully characterized using FTIR and UV-Vis measurements which have shown that polymerizations have been carried out. XPS has certified that the clay has undergone a cationic exchange of sodium by the cationic surfactant. X-ray diffraction confirmed that polymers/copolymers were largely incorporated into the clay. Good electrical response and improved thermal stability for the synthesized nanocomposites have been observed.
Auteur(s) : بن زكورة العونية
Mots-clés : جائحة كورونا، البيئة، التلوث البيئي، التدهور البيئي،التكنولوجيا النظيفة،
ISSN : 6774- 2600 | E-ISSN : 6774- 2600 | Vol : 9, N° : 1, pp : 707-728
Résumé : The research deals with the subject of environemental protection in Algeria in the framework of sustainable development and biodiversity through a regulation of the negative behaviour of the citizen by using a range of texts and procedures that put an end to the aggressions suffered this environement. The study concluded that when it comes to preserving the evironment, it is not enough to legislate, but rather to coordinate all the efforts of stakeholders to mitigate the risks of various types of pollution. Abstract: La recherche traite du sujet de la protection de l’environnement en Algérie dans le cadre du developpement durable et la biodiversité à travers une régulation du comportement négatif du citoyen en usant d’une panoplie de textes et de procédures qui mettent fin aux agressions que subit cet environnement. L’étude a conclu à une réalité ; quand il s’agit de préserver l’environnement, il ne suffit pas légiférer ne suffit pas mais plutôt coordonner tous les efforts des parties prenantes pour atténuer les risques de pollutions diverses. يعالج البحث مسألة حماية البيئة في الجزائر في إطار تحقيق التنمية المستدامة والتنوع البيولوجي، من خلال ضبط السلوك السلبي للمواطن بمجموعة من القوانين و الإجراءات التي تحد من التدهور البيئي. توصلت الدراسة إلىحقيقة أنه عندما يتعلق الأمر بحماية البيئة فلا يكفي الإعتماد على سن القوانين و انما يرتبط بتكاتف الجهود بين كل الأطراف المعنية للحد من خطر التلوث بمختلف أشكاله.
Auteur(s) : MS. Guellil S. Ghouali O. Khedir D. Benabou H. Ayad SE. Sari-Hassoun
Mots-clés : Sustainability GDP Energy consumption Goal programming model Work force Environment
Résumé : Objective programming models propose an explanatory framework to look at multi-criteria issues, including a couple of clashing targets. Genuine issues regularly include uncertain data, which makes weighted objective programming (WGP) models the most appealing decision. This article offers a WGP model that consolidates ideal resource distribution to simultaneously satisfy planned objectives on economic improvement, vitality utilization, workforce, and ozone-depleting substance (GHG) emanation decrease associated with key financial areas of Algeria. The model offers significant encounters to chiefs for fundamental arranging and adventure portions towards doable progression. We exhibit the authenticity and substantiality of the model through a numerical case.
Auteur(s) : Amina Elbatoul. Dinar Samir. Ghouali Rachid. Merzougui Attaouia. Bentahar Boualem. Merabet
Mots-clés : ACWKC; C300M shelf; CICK; cloud; GUSQ; IP-MSAN; optical infrastructures
ISSN : 2191-6322 |
Auteur(s) : N. E-h. Bouabida, A. Hachemaoui, A. Yahiaoui, H. Gherras, A. Belfedal, A. Dehbi, , A. H I. Mourad
Mots-clés : Copolymer synthesis, solubility, poly(pyrrole-co-2-nitrocinnamaldehyde), pyrrole, 2-nitrocinnamaldehyde
ISSN : 1560-0904 | Vol : 62, N° : 02,
Résumé : Poly(aniline-co-4-bromoaniline) nanocomposites were prepared via in situ polymerization in different
molar ratio in the presence of Cu2+−monmorillonite. The X-ray diffraction confirmed that the basal
space of Cu2+−montmorillonite increased after the organophilization. Poly(aniline-co-4-bromoaniline)/
Cu2+−monmorillonite nanocomposites were prepared by intercalating of aniline and 4-bromoaniline
with treated organically layers of Cu2+−monmorillonite following by polymerization initiated by ammonium
peroxdisulfate. The nanocomposites were characterized by FTIR, XRD, and UV–Vis spectroscopy.
Auteur(s) : Djilali Benyerou, El Bahri Ould Chikh, Habib Khellafi, Hadj Miloud Meddah, Ali Benhamena, Kaddour Hachelaf, Abdellah Lounis
Vol : 15, N° : 55,
Résumé : Friction stir spot welding (FSSW) is a very important part of conventional friction stir welding (FSW) which can be a replacement for riveted assemblies and resistance spot welding. This technique provides high quality joints compared to conventional welding processes. Friction stir spot welding (FSSW) is a new technology adopted to join various types of metals such as titanium, aluminum, magnesium. It is also used for welding polymer materials which are difficult to weld by the conventional welding process. In various industrial applications, high density polyethylene (HDPE) becomes the most used material. The parameters and mechanical properties of the welds are the major problems in the welding processes. In this paper, we have presented a contribution in finite element modeling of the friction stir spot welding process (FSSW) using Abaqus as a finite element solver. The objective of this paper is to study the HDPE plates resistance of stir spot welding joints (FSSW). First, we show the experimental tests results of high-density polyethylene (HDPE) plates assembled by friction stir spot welding (FSSW). Three-dimensional numerical modeling by the finite element method makes it possible to determine the best representation of the weld joint for a good prediction of its behavior. Comparison of the results shows that there is a good agreement between the numerical modeling predictions and the experimental results.
Auteur(s) : Amina Elbatoul. Dinar Samir. Ghouali Boualem. Merabet Mohammed. Feham
Mots-clés : ASTM Elecsys NTP Optical DNA biochip UNIX
pp : 89-101
Résumé : DNA biochip technology (especially in the optical field) can study a large amount of nucleic acid records at high throughput. It makes viable the simultaneous scrutiny of quite a few of tens of thousands of genes belonging to a healthy or diseased biological sample in terms of its genome (DNA). This article overviews optical DNA biochips as well as the Network Time Protocol (NTP) protocol deployment for synchronization among the collection database and the optical biochip automaton via the ASTM Elecsys protocol for better real-time detection with diagnosis of genetically mutated cancer. The present study utilizes the UNIX Server platform and NTP to synchronize communication between servers and optical DNA. Section 7.4 brings in automates.
Auteur(s) : Mohamed Amine MEDEBBER, Noureddine RETIEL, Belkacem OULD SAID
Mots-clés : heat transfer and mass
Vol : 05, N° : 01, pp : 4 3 0 – 4 3 9
Résumé : This study concerns the two-dimensional numerical simulation of the double diffusive
convection in cylindrical vertical annular cavity. The vertical walls are maintained at
different uniform temperatures and concentration. The governing equations are solved
numerically using the finite volume method. The coupling between the continuity and
momentum equations is effected using the SIMPLER algorithm. Numerical analysis has
been carried out for a wide range of the buoyancy ratio (N=0.8 and 1.3). The influence
of the buoyancy ratio (N) parameters on the streamlines, isotherms, isoconcentration,
average Nusselt number and Sherwood numbers has been numerically investigated in
detail.
Auteur(s) : Habib Bouzir, Gherici Beldjilali
Mots-clés : Trans-Sasakian manifolds, Kählerian manifolds; product manifolds
Vol : 13, N° : 2,
Résumé : It’s shown that for some changes of metrics and structural tensors, the product of two transSasakian manifolds is a Kählerian manifold. This gives new positive answer and more generally
to Blair-Oubin˜a’s open question. (See [7] and [17]). Concrete examples are given.
Auteur(s) : Amina Elbatoul. Dinar Boualem. Merabet Samir. Ghouali
Résumé : As of now, all servers have an equipment or programming clock to which reference is made to time stamp records, exchanges, messages, and so forth. This clock, albeit structured around a quartz oscillator, floats like any customary watch, which implies this common watch cannot a match to such created machines that are networked and share common resources like file systems. For example, UNIX is a development tool which makes command, based on its work on comparing file modification dates. Similarly, the correlation of log messages from several systems becomes very difficult if they are not at the same time. In this article, we will concentrate on this topic by designing a server utilizing the NTP convention since the primary “focus” of the NTP usage is UNIX frameworks, and to be more explicit, we will see the management of the NTP server with the Chrony tool.
Auteur(s) : K. Ismaiel, T.M. Mohamed, S. Abderrahmane.
Mots-clés : Tridiagonal Toeplitz matrix, square root, persymmetric matrix, eigenvalue.
ISSN : 2313-626X | Vol : 7(2020)(7), N° : 7, pp : 92-94
Résumé : In this paper, we present an explicit formula to find square roots of a tridiagonal Toeplitz matrix, and we show that these square roots have the form of a persymmetric matrix with examples to illustrate.
Auteur(s) : MELIANI AMINA
Mots-clés : MDR, P AERUGINOSA
ISSN : 1611-2156 | Vol : 19, pp : 1-4
Résumé : It was with great interest that we have read the review article entitled “Antibiotic re-
sistance in Pseudomonas aeruginosa: mechanisms and alternative therapeutic strategies”. We truly thank Pang and colleagues for this successful research review (Pang et al., 2019).
A myriad of factors involved in the P. aeruginosa resistance are provided in this overview.
Interestingly, these multidrug resistant (MDR) bacteria have engaged an intrinsic, acquired and adaptive antibiotic resistance. In thepresent contribution, we are highlighting how biofilm-mediated
resistance comes into play.
Auteur(s) : Yasser Bouzid, Mehdi Zareb, Houria Siguerdidjane, Mohamed Guiatni
Mots-clés : Reference model-based control Nonlinear control Robust Control IDA-PBC ADRC ESO Quadrotor
ISSN : 0921-0296 | E-ISSN : 1573-0409 | Vol : 100, N° : 1, pp : 597–614
Résumé : It is relevant to develop an adequate control algorithm for quadrotors that guarantees a good compromise robustness/ performance. This compromise should be ensured with or without external disturbances. In this paper, we investigate and apply a revisited formulation of a reference model-based control strategy by introducing a boosting mechanism. This mechanism uses an Extended State-based Observer (ESO) to estimate the uncertainties and variety of disturbances. The estimation is continually updated and rejected from the main control loop. The reinforcement principle is inspired from the popular Active Disturbance Rejection Control (ADRC) technique in order to enhance the robustness ability of a nonlinear reference model-based control strategy (i.e. Interconnection and Damping Assignment-Passivity Based Control (IDA-PBC)). The obtained controller is augmented by an additional input, which is derived via sliding modes framework to handle the estimation errors and ensure asymptotic stability. This combination leads to promising results by improving the nominal control technique. The primary results are shown through numerical simulations and are confirmed, experimentally, with several scenarios.
Auteur(s) : Mokhtar Besseghier; Djebbar Ahmed Bouzidi
Mots-clés : OFDM/OQAM Estimation CFO
ISSN : 1089-7798 | E-ISSN : 1558-2558 | Vol : 24, N° : 7, pp : 1451 - 1454
Résumé : To solve the performance degradation due to Carrier Frequency Offset (CFO) for OFDM/OQAM system, a new blind CFO estimation method is proposed in this letter. This method uses the header structure of the transmitted signal by considering that there is an OFDM/OQAM symbol of null-valued OQAM symbols before the first one and exploits the orthogonality among subcarriers as well as the orthogonality between synthesis and analysis filter banks to estimate the CFO. Therefore, without compromising the spectral efficiency of OFDM/OQAM system this method can estimate accurately the CFO. Simulation results illustrate the effectiveness of the proposed method.
Auteur(s) : Assia Hebri / Khelil Sara.
Mots-clés : la comptabilité des ressources humaines, outils de l’audit social, la gestion des RH, la performance du capital humain, Indicateurs.
ISSN : 2661-7374 | Vol : 03, N° : 05, pp : 57-69.
Résumé : L’objectif de cette recherche, était de déterminer les outils de l’audit social dans la filiale de Tube, groupe Chiali sidi BelAbes, Algérie. Après une analyse d’un échantillon de charges du personnel sous forme l’indicateurs ratios, et de diagrammes et par l’utilisation d’un questionnaire sur les méthodes de calcul des salaires et la politique de rémunération, on a constaté qu’Il ya une absence d’un système d’évaluation des connaissances dans la rémunération du personnel.
Auteur(s) : Assia Hebri.
Mots-clés : : مناخ الأعمال ، الشركات العائلية الأوربية ، النجاعة ، البارومتر السنوي 2017 ، الإبداع والتطوير .
ISSN : 2661-779X | Vol : 04, N° : 01, pp : 274-285.
Résumé : تهدف هذه الدراسة إلى تحليل الأثر الكبير الذي تحدثه التفاعلات العامة والخاصة للشركات العائلية مهما كان حجمها ونشاطها مع مناخ الأعمال السائد في موقعها الجغرافي و تفاعلها مع بيئتها الداخلية والخارجية ومسؤوليتها اتجاه الأطراف أصحاب المصلحة - أكد الاستبيان السنوي لعام 2017 من إعداد الفدرالية الأوربية للشركات العائلية EBF ومجموعة مستشاري شركة مرافقة الأعمال العائلية KPMG ، بعد أن حقق نسبة أكثر من 1100 إجابة من مالكي الشركات العائلية في كل مكان في أوروبا لسنة 2017، على قوة روابط الشركات العائلية الأوربية على الرغم من التحديات التي تواجهها يوميا وإعادة استثمار أرباحهم والبحث عن الجديد و الفرص التطويرية التي تسمح لهم بخلق ظروف ملائمة للنمو المستدام لشركاتهم .
Auteur(s) : C Boudia, A Bengueddach, H Haffaf
Mots-clés : University Teaching Strategies, Oriented-Object Programming, Collaborative Learning,
ISSN : 1854-3871, 0350-5596 | Vol : 43, N° : 1, pp : 129–144
Résumé : Several strategies and methods have been designed and tested to allow students to have better teaching
and learning of programming concepts and training their programming skills acquired. In our
university, old and classic pedagogical methods are still used in the learning of Oriented-Object
Programming (OOP). This paper explores the experimentation of a pedagogical approach designed for
Mostafa Stambouli Mascara University’s computer sciences students to enhance their chances to get an
effective teaching using a collaborative learning and early introduction of current technologies. The
study was made of 108 second year informatics students’ for two semesters (October–January 2016-
2017, September-December 2017-2018) who were identified in a controlled experience for collaborative
learning OOP in lab session. Students gathered into predetermined groups based on initial test and
some setting. The students are supposed to share the same programming assignment by distributing
roles according to global pedagogical scenario for problem-resolving activities. This experience allows
the teachers to apply this strategy and see students in closer and permit them to express their problems
and search together for solutions. The principal objective was to offer a new experience to motivate
students and make this design a smart opportunity to have better programming performance.
Furthermore, as a result of testing this new strategy, the students’ academic progress is clear. A
questionnaire was distributed with the purpose of analyzing students’ motivation and satisfaction levels
alongside the effects of the experiment. Results show that students found that among other benefits this
method facilitates the learning process.
Auteur(s) : BELDJILALI gherici
Mots-clés : Almost contact metric structure, Almost Golden structure, Golden sectional curvature
ISSN : 1307-5624 | Vol : 13, N° : 1, pp : 1-8
Résumé : In this paper, we introduce a new class of almost Golden Riemannian structures and study their essential examples as well as their fundamental properties. Next, we investigate a particular type belonging to this class and we establish some basic results for Riemannian curvature tensor and the sectional curvature. Concrete examples are given.
Auteur(s) : Mohamed Amine Medebber, Nourddine Retiel, belkacem Ould said, Abderrahmane Aissa, and Mohammed El Ganaoui
Mots-clés : Computational fluid mechanics; Coupled Natural convection with Surface radiation; Finite Volume Method; Partially Annular; Nusselt Number
E-ISSN : 2261-236X | Vol : 307, N° : 01029 (2020),
Résumé : A transient two dimensional study of free convection in a vertical cylinder partially annulus is conducted numerically. Uniform temperature is imposed cross a vertical wall, while the top and bottom walls are adiabatic. The governing equations are solved numerically by using a finite volume method. The coupling between the continuity and momentum equations is effected using the SIMPLER algorithm. Solutions have been obtained for Prandtl numbers equal to 7.0, Rayleigh numbers of 103 to 106 and height ratios 0.5. The influence of physical and geometrical parameters on the isotherms, velocity fields, average Nusselt has been numerically investigated.
Auteur(s) : Yasser Bouzid, Houria Siguerdidjane, Elmehdi Zareb
Mots-clés : Quadrotor, autonomous system, internal model control, PI controller
ISSN : 0959-6518 | E-ISSN : 2041-3041 | pp : 1-13
Résumé : As known, internal model control is equivalent to a PI or a PID controller provided that the mathematical model associated to the process to be controlled is of first or second order respectively. So, to go beyond these particular cases and to make an extension in bringing more theoretical results, the article proposes a method to reach the equivalence between an internal model control and a PI controller regardless of the model order. To this end, the key idea consists of using a specific filter that exhibits superior robustness level compared to the classical filter and further leads to get a structure of a PI controller whatever the order of the model is. The developed procedure constitutes the main contribution of this article. To meet given set of specifications, the controller parameters are tuned through a straightforward analytic way using the dynamics of the tracking error. The proposed tuning strategy constitutes another contribution of the article. Furthermore, to evaluate the efficiency level of this procedure, an application to control an autonomous vehicle is described and the simulation results are shown to be satisfactory confirmed by a series of experimental tests.
Auteur(s) : M Khaldi, M M Bouziane, A Vivet, H Bougherara
Mots-clés : biodegradable; cellulose and other wood products; fibers; hydrophilic polymers; mechanical properties
ISSN : 0021-8995 | E-ISSN : 1097-4628 | Vol : 137, N° : 137,
Résumé : Composites reinforced with plant‐based fibers present a high potential for valorization in new industrial applications due to their good specific mechanical characteristics, renewability, and recyclability. In order to accelerate their wide industry adoption, it is critical to assess their behavior and durability in heat and humid environments. This article aims at investigating the effects of temperature and relative humidity (RH) on the longitudinal and transverse mechanical properties of the lignocellulosic fibers extracted from alfa plant (Stipa tenacissima L). For this purpose, tensile and nanoindentation tests were performed on elementary alfa fibers subjected to a thermal cycle of 200°C. The fibers were held at various periods of 15, 30, 60 and 120 min. The test results showed that the longitudinal and transverse Young's moduli are moderately affected by short thermal cycles having duration of 15–30 min. However, for longer thermal cycle (i.e., 2 hr), a degradation of 21% for the transverse modulus was recorded. This degradation doubled for the longitudinal modulus (43 vs. 21%). A similar trend was observed for the breaking strength. This study also showed that the RH strongly affects the mechanical performances of alfa fibers.
Auteur(s) : S. Bousalem
Mots-clés : Hybrid materialsPolyanilineZnOOptical propertiesElectrochemical properties
ISSN : 0009-2614 |
Résumé : Hybrid-materials were prepared via chemical polymerization in presence of aniline with various amounts of ZnO. The structural, functional, optical, morphological and electrical properties of nanocomposites were investigated by XRD, FT-IR, UV-Visible, TGA, SEM and electrical conductivity. XRD and SEM analysis shows the formation of nanocomposite and confirms the amorphous and crystalline nature of material. FT-IR spectrum reveals the functional groups present in the samples and the electroactive and optical properties were affected. Results showed that our nanocomposites exhibited a direct optical energy gap that decreased from 3.12 to 2.76 eV with the increment of the amounts of ZnO in nanocomposite.
Auteur(s) : Abbes Beloufa, Driss Bouguenna, Nawel Kermas & Donat Josef As
ISSN : 0361-5235 |
Auteur(s) : T.M. Mohamed, K. Ismaiel, S. Abderrahmane.
ISSN : 1607-2510 | Vol : 20(2020), pp : 199-203
Résumé : A finite Toeplitz matrix T is normal if and only if it is a rotation and a translation of a Hermitian Toeplitz matrix (Type I) or it is a generalised circulant (Type II). In this paper, we show that the powers of a Type II matrix T are also Type II.
Auteur(s) : Z. M'hamed ; K. Ali
Mots-clés : Partenariat ; Accord d’association ; Modèle d’équilibre général calculable ; Matrice de comptabilité sociale ; Algérie ; Union européenne
E-ISSN : 2600-6502 | Vol : 13, N° : 3, pp : 326-339
Résumé : Dans le cadre de l’analyse des effets des accords d’association euro – méditerranéens, nous essayerons d’utiliser un modèle d’équilibre général calculable, afin de quantifier cet impact. Pour cet objectif, nous élaborerons une matrice de comptabilité sociale, qui nous permettra de valider notre modèle et d’effectuer nos simulations. Nous analyserons les scénarii relatifs à la substitution entre les importations et la production nationale, par les consommateurs et les producteurs. Pour la résolution du modèle, nous utiliserons le logiciel GAMS.
Auteur(s) : Assia Hebri.
Mots-clés : التنوع ، إدارة التنوع ، الشركة الدولية ، التدريب الدولي ، شركة زين للاتصالات
Vol : ?????? 6,, N° : ????? 2, , pp : 133-151
Résumé : تهدف هذه الدراسة إلى إبراز الدور الإستراتيجي لإدارة التنوع الثقافي في الموارد البشرية ، الذي يعد من أكثر المواضيع أهمية و هذا نظرا للقناعة المتزايدة بأهمية إدارة وتنمية التنوع في الموارد البشرية كأحد العناصر العامة والمؤثرة في نجاح تلك المنظمات، مع الإشارة إلى حالة شركة زين للاتصالات التي حققت ميزة تنافسية مهمة في ميدان نشاطها بفضل استقطاب المواهب من مختلف الجنسيات وتطويرها وخلق بيئة عمل مناسبة بالتركيز على النجاعات العملية و ليس الاختلافات التي يمكن التعامل معها بإتباع استراتيجيات مدروسة لإدارة التنوع التي أصبحت من الأعراف الدولية اليومية في أماكن العمل.
Auteur(s) : Z. M'hamed ; R. Lotfi
Mots-clés : Partenariat ; Accord d’association ; Modèle d’équilibre général calculable ; Matrice de comptabilité sociale ; Algérie ; Union européenne
E-ISSN : 2602-5191 | Vol : 6, N° : 2, pp : 22-46
Résumé : Dans cette étude, nous tentons d’analyser les perspectives de l’économie algérienne dans le contexte actuel de chute des prix pétroliers sur le système bancaire et le développement économique. Pour cela, nous discutons la question de la gouvernance de système bancaire algérien et ses défis face à cette nouvelle conjoncture pétrolière, et qui place l’Algérie devant des choix difficiles accompagnée par un recul de 30% de la fiscalité pétrolière, une essence pour les plans de dépenses du gouvernement.
Auteur(s) : Mokhtar Besseghier; Djebbar Ahmed Bouzidi; Zouggaret Abdelhak; Iyad Dayoub
Mots-clés : Estimation
ISSN : 1018-4864 | E-ISSN : 1572-9451 |
Résumé : Orthogonal frequency division multiplexing based cooperative system using Alamouti space–time block coding at relay node represents an alternative solution to achieve better connectivity and significant enhancement to the data rate in wireless fading channels. But, these advantages cannot be achieved without an efficient estimation of the channels which becomes more challenging for cooperative communications. This paper addresses the joint channel estimation and data detection for cooperative communication systems. Indeed, equispaced pilot symbols are used by maximum likelihood (ML) algorithm to derive channels estimator, and then equalizers are calculated and applied to improve receiver data detection. The main contribution of our work is the development of the ML estimator, the corresponding Cramer–Rao lower bound, mean square error, signal to interference plus noise ratio, outage probability, bit error probability and the use of simulations to demonstrate the superior performances of the proposed methods.
Auteur(s) : Samir Ghouali, Mohammed Seghir Guellil, Mostefa Belmokaddem
ISSN : 978-3-030-37206-4 | Vol : 102, pp : 329-337
Mots-clés : سوق الشغل- مرفق التنصيب- الإتفاقية الدولية رقم 181 - عروض العمل- طلبات العمل-ضبط سوق العمل- الوكالة الوطنية للتشغيل- الهيئات الخاصة للتنصيب.
E-ISSN : 2600-6952 | Vol : 33, N° : 04, pp : 121-153
Résumé : لم يمانع المشرع الجزائري من فتح الوساطة في التشغيل لأشخاص القانون الخاص طبيعيين ومعنويين ،لكنه حصر مشاركتهم في تسجيل العمال،إنتقائهم،وتقديمهم للهيئات المستخدمة قصد تنصيبهم ومن دون الإخلال بالإعتراف لهم بالبحث عن عروض العمل وجمعها وتوزيعها وهو ما يعني أنّه حصر مهمتهم في الوساطة في التنصيب، ما جعله يسمي الأشخاص التي تتولى هذه المهمة بالهيئات الخاصة للتنصيب بدل وكالات الإستخدام الخاصة وفق ما حددته منظمة العمل الدولية.
تتناول الورقة البحتية المقدّمة تحديدا لماهية وكالات الإستخدام الخاصة والشكل الذي اختار المشرع الجزائري أن تظهر به أو ما يعرف بهيئات التنصيب الخاصة كاستجابة لتحرير الوساطة في التشغيل،من خلال إعادة النظر في آليات ضبط سوق العمل وتنظيمه ،لتنتقل الوساطة في التشغيل من الإحتكار الكلي للوكالة الوطنية للتشغيل إلى المشاركة المقيّدة لوكالات الإستخدام الخاصة.
ABSTRACT
The Algerian legislator did not object to the opening of employment mediation to private law persons; however, he limited their participation in the registration, selection and submission of workers to the bodies used for their inauguration without prejudice to their recognition of the search, collection and distribution of work. , which means that inventory their mission on mediation at the inauguration, who undertake this task to the private bodies for installation, instead of private employment agencies as defined by the International Labor Organization.
This paper deals with the specific nature of the private employment agencies and the form in which the Algerian legislator chose to be represented by the so-called private instigators, with the aim of liberalizing employment mediation, by revising the mechanisms of regulating and regulating the labor market, in order to restrict participation of private use agencies
Auteur(s) : Samir Ghouali, Mohammed Moulay, Mohammed Feham
Mots-clés : Electrical Continuity; MDF; MSAN; Dispatcher; ZTE
ISSN : 2180-1843 | E-ISSN : 2289-8131 | Vol : 11, N° : 04, pp : 19-23
Résumé : The continuity test of a telephone line is a technique used very often by every Telecom site engineer. Continuity refers to communication that does not face any interruption. Very often, the continuity measurement takes place during troubleshooting to ensure that the lines are intact. The work presented in this paper is based on the principle of MDF continuity rule lines for MSAN site. It presents the practical realization of a continuity tester circuit to verify several telephone lines simultaneously, specifically 24 pairs (24 subscribers) at the same time. Our solution suggested for making troubleshooting in one of the outages/ malfunctions more flexible and fluid in terms of intervention and time for repair. A case study involving 18 sites in two different regions in Algeria, Constantine (without circuit) and El Oued (with circuit) was conducted and the results showed there was a gain ratio estimated at about 338/1361 (Min).
Auteur(s) : A. Mazot
Mots-clés : locuteur, énonciateur, effacement énonciatif, engagement énonciatif, On.
ISSN : 2602+7585 | N° : 4, pp : 228-240
Résumé : Notre étude s’inscrit dans le cadre de la théorie de la linguistique de l’énonciation. Notre corpus est composé d’un ensemble d’énoncés tirés de10 numéros du Quotidien d’Oran et qui s’inscrivent dans une période qui s’étend de janvier à octobre 2019. Nous nous attachons dans cette présente recherche à analyser une marque linguistique permettant au locuteur-journaliste d’introduire d’une façon explicite ou implicite son point de vue dans l’énoncé tout en exprimant des attitudes envers son énoncé et son interlocuteur. Nous nous inspirons des recherches menées par Vion ( 2001) et Rabatel ( 2003,2004, 2005) et qui consistent à proposer un appareil formel des procédés de l’effacement énonciatif. En s’inscrivant dans cette optique, nous proposons une analyse de l’usage du pronom On dans les articles du Quotidien d’Oran.
Auteur(s) : Mohamed El-Amine Bekhti, Ahmed Yahiaoui, Aicha Hachmaoui, Abdelghani Benyoucef
ISSN : 1021-9986 | Vol : 38, N° : 6, pp : 127-133
Résumé : Au niveau du laboratoire, nous avons étudié les effets de divers facteurs, la concentration initiale d'ions métalliques, le pH de la solution, la quantité de boue utilisée et le temps de contact, sur l'adsorption des ions zinc et plomb sur le matériau du barrage (Mascara, Algérie ). Les constituants des sédiments limoneux sont le quartz, la calcite et un mélange d'argiles. Le temps d'équilibre était de l'ordre de 60 min. Le diagramme d'adsorption est lisse et continu conduisant à la saturation, suggérant la possible couverture monocouche d'ions zinc et plomb à la surface de l'adsorbant. Le degré d'adsorption augmente avec l'augmentation du pH. De plus, l'adsorption des métaux augmente avec l'augmentation de la quantité d'adsorbant. La modélisation de l'adsorption a été réalisée en utilisant les modèles d'adsorption de Langmuir et Freundlich pour déterminer les paramètres mécanistiques associés au processus d'adsorption. Le modèle isotherme Langmuir-Freundlich était le meilleur pour décrire les données expérimentales. La capacité de sorption maximale s'est avérée être de 42,73 et 131,57 mg/g pour le Zn2+ et le Pb2+, respectivement.
Auteur(s) : د.بزاوية مختار
Mots-clés : الرحالة- الجوانب العلمية- الجزائر- اللغويات
ISSN : 2170_1636 | E-ISSN : 2600_6324 | Vol : 09, N° : 03, pp : 273-291
Résumé : تميزت بعض الرحلات بنشاط علمي متميز، فأضحت تزخر بالعلم والأدب والتاريخ والاجتماع، وغيرها من الفنون، ومن أنفس هذه الرحلات رحلة الطيب المهاجي التي وسمها بــــ : "أنفس الذخائر وأطيب المآثر". ولقد حوت هذه الرحلة من العلوم اللغوية والشرعية ما لا يخفى على اللبيب، فالشيخ الجليل يمثل ظاهرة دينية إصلاحية جمعت إلى معانيها موهبة أصيلة، أهّلته لأنْ يحتل مكانة عالية في العلوم اللغوية والشرعية، فهو من العلماء الجزائريين الذين أدخلهم التاريخ من بابه الواسع.
ومن البديهي أنّ العالم لا يمكن أن يُبرِز للناس علمَه وإنتاجه وهو منغلق على نفسه، لذا قام شيخنا برحلات علمية مختلفة كرحلته إلى الحرمين الشريفين وتونس وغيرهما، ولقي عدة مشايخ وأخذ عنهم الإجازات، مما أسهم في تفاعل ثقافي كبير بينه وبين علماء الأمصار الإسلامية. وقد اكتشفوا من خلال هذا التفاعل قدرة الشيخ وموهبته العلمية الخارقة.
كما حوت هذه الرحلة مسائل علمية دقيقة في العلوم اللغوية كالنحو والصرف، والعلوم الشرعية وفتاوى ونوازل كثيرة، مما أبرز تمكّن الشيخ من العلوم واللغوية والشرعية، وقدرته العجيبة في تناول هذه المسائل بالتحليل العميق، والرؤية النافذة. ولقد ركزت في مداخلتي على بعض هذه الجوانب العلمية باعتبارها عاملا مهما من عوامل التفاعل الثقافي بين العلماء الجزائريين وغيرهم.
Auteur(s) : Beldjilali gherici
Mots-clés : Golden manifold; Almost contact metric manifold.
ISSN : 2219-5688 | Vol : 9, N° : 1, pp : 594-603
Résumé : In this work, we have dealt with almost contact metric structures induced by
Golden structures and simultaneously as one can be obtained from the other, and provided the
following results besides some side ones. Various examples are discussed.
Auteur(s) : Brahim Dehri; Mokhtar Besseghier; Djebbar Ahmed Bouzidi; Iyad Dayoub
Mots-clés : STBC-OFDM
ISSN : 1751-8628 | E-ISSN : 1751-8636 | Vol : 13, N° : 17, pp : 2827 - 2833
Résumé : Here, the authors propose a robust blind digital modulation classification (BDMC) algorithm for space time block coding (STBC)-based MIMO-OFDM system in the presence of carrier frequency offset (CFO) and channel estimation errors. Previous papers published on the topic of modulation identification were limited to single-carrier systems operating over frequency-flat channels. The problem of joint channel and CFO estimation in conjunction with blind digital modulation classification for STBC-OFDM in frequency selective channel and in the presence of the impulsive noise has not been addressed before to the best of their knowledge. To cope with performance degradation of BDMC due to CFO and channels errors, they propose joint semi-blind CFO and channels estimation methods. Higher order statistics (HOS), used for feature extraction, are combined with pattern recognition methods to solve the modulation identification problem. The main contribution of their work is the development of estimators, the study of their impacts on the blind classification capability, and the use of simulations to demonstrate the superior performance of the proposed algorithms.
Auteur(s) : U. Mohan Rao ; I. Fofana ; A. Betie ; M. A. Senoussaoui ; M. Brahami ; E. Briosso
Mots-clés : Reactors , Aging , Power transformer insulation , Oil insulation , Power transformers
ISSN : 0883-7554 | E-ISSN : 1558-4402 | Vol : 35, N° : 6, pp : 33 - 42
Résumé : Transformers are one of the most strategic components in balancing the voltage levels and hence a high priority is given to their performance [1]. It is established that, insulation technology plays a critical role in judging the performance and service life in oil filled apparatus [2]. Performance of the insulation system depends mainly on the deterioration behavior of insulation oil and paper. The mechanisms that are responsible for premature aging of oil/paper insulation are almost the same in all the oil filled apparatus. Yet, there will be a significant difference in the intensity of the aging mechanisms in different apparatus. This intensity is attributable to rating, design, and duration of operation for different machines. The detailed discussions on these mechanisms are presented in the subsequent sections of this paper. However, aging of service insulants is unavoidable and is to be maintained at a lower rate or arrested to the greatest possible extent, such that, catastrophic failures and unscheduled outages may be mitigated [3]. Normally, utilities follow scheduled condition monitoring activities to avoid the consequences of premature aging. Hence, knowledge on these in-service condition monitoring activities will be helpful in understanding the exact deterioration rate of the insulation system. Real time in-service experience of several transformer fleets that belong to United Kingdom utilities are reported in [4]. An early degradation of insulation is noticed through increase in acidity and furan concentration in oil for several transformers in the fleet. Authors investigated this early degradation in different perspectives including loading conditions, manufacturers, and oil chemistry changes. It is inferred that changes in oil chemistry is an important attribute for early degradation and hence utilities are advised to adopt different asset management strategies for affected and unaffected transformers in a fleet. Recently, failure rate data of servic...
Auteur(s) : بن زكورة العونية
Mots-clés : Sukuk, economic development, social development, types of Sukuk, the challenges of Sukuk , Malaysian Experience Mots clés : sukuk financiers islamiques, développement économique, développement social, types de sukuk, les défis sukuk financiers islamiques, Expérience malaisienn
ISSN : 6820- 2600 | E-ISSN : 2600-6820 | Vol : 10, N° : 2, pp : 208-222
Résumé : This study is designed to identify the Islamic financial sukuk as one of the Islamic financial instruments for mobilizing saving and for the use of investmenT instruments to contribute to the financing for economic and social development process. The financial sukuk is known as financing instruments used in Islamic financial instruments according to the regulations of Islamic law (chari’a), and vary the versions of the diversity and versatility of the exporting as well as nature. Despite the increasing trend toward these instruments according to the Islamic finance act of 2018 and following the successful experience of Malaysia, but this deal funding instruments still sees many challenges. Résumé : Cette étude vise à identifier le sukuk financiers islamiques comme l’un des instruments financiers islamiques destinés à mobiliser l’épargne à utiliser les outils d’investissement pour contribuer au financement du processus de développement économique et social. les sukuk financiers sont défini comme étant des outils de financement utilisés dans les établissements financiers islamiques selon les règlements de la loi islamique (chari’a). ses formes sont variées selon leurs utilisations. Leurs émetteurs et leurs natures. Malgré la tendance croissante vers l’utilisation de ces outils conformément au rapport financier de l’année 2018 et à la suite de l’expérience réussie du Malaisie, leur utilisation est confrontée à plusieurs défis
Auteur(s) : بن زكورة العونية
Mots-clés : البيئة، الجباية البيئية،التنمية المستدامة، الاقتصاد الأخضر
ISSN : 1111-5149 | E-ISSN : 2430- 2588 | Vol : 20, N° : 2, pp : 291-312
Résumé : ملخّص: يهدف هذا البحث للتعرف على دور تكنولوجيا المعلومات في تحسين جودة الخدمات المصرفية، لاسيما على مستوى البنوك الإسلامية. يظهر أثر استخدام هذه الأخيرة في التغيير الجذري للمعاملات المصرفية من شكلها التقليدي الذي يرتكز على الاتصال المباشر بين البنك والعميل، إلى الشكل الالكتروني الذي يعتمد في أساسه على تقليل تكاليف الخدمة المصرفية بالاعتماد على الوسائل التكنولوجية للوصول إلى أكبر شريحة من المتعاملين. إن استعمال التكنولوجيا على مستوى المصارف الإسلامية، ولاسيما المصرف محل الدراسة، جعل من تقديم وعرض الخدمات الالكترونية أمرا حتميا يفرض نفسه بهدف تعزيز قدرتها التنافسية. فقد سعى بنك السلام جاهدا إلى توفير جملة من الخدمات الالكترونية لعملائه، وذلك بتوفير المعلومات اللازمة عن البنك وفروعه عبر موقعه، مع السماح لهم بالتعرف على مختلف الخدمات المقدمة سواء التقليدية أو الالكترونية. زيادة على توفير البيانات المتعلقة بنشاطه ومستوى أدائه من خلال نشر مختلف البيانات اللازمة ضمن تقاريره السنوية. ما توصلنا إليه ، هو قدرة البنك على توظيف تكنولوجيا المعلومات بما يسمح له تحقيق جودة الخدمة المصرفية، قدرة توسيع شريحة المتعاملين معه و تحسين أدائه في ظل تغيرات البيئة المصرفية. Abstract : This research aims to identify the role of the technology of information in improving quality of the banking services, particularly at the level of the Islamic banks. the impact of using this latter appears in the radical change of the banking transactions from its traditional shape which is based on the direct contact between bank and customer, to the electronic which based to reduce the costs of banking services through reliance on technological means to access to the largest slice of dealers. The use of technology on the level of Islamic banks, especially banks under study, made from provide electronic services inevitable imposes itself in purpose to enhance their competitiveness. AL Salam bank- Algeria has endeavoured to provide a range of e-services to its clients and that by providing the necessary information about the bank and its branches through its location ,as well as allowing them to identify the various services provided by both conventional and electronic. Increase the availability of data related to its activity and the level of its performance from deployment various necessary data in his annual reports. What we have achieved is the ability of the bank to employ information’s technology to allow the achievement of the quality of the banking service, ability to expand the segment of its dealers and improve its performance under changes in the banking environment
Auteur(s) : د.بزاوية مختار
Mots-clés : المناظرات؛ المحاورات؛ النحاة ؛ اللغويون؛ الاختلافات.
ISSN : 2335-1586 | E-ISSN : 2600_6324 | Vol : 08, N° : 04, pp : 509-530
Résumé : كانت نشأة النحو لغايات نبيلة وهي صون القرآن الكريم واللغة العربية من اللحن والتغيير، وقد كان النحو العربي في بدايته يزخر بمجالس العلماء من القراء واللغويين ورواة الأشعار، فيتدارسون مسائل العربية ويستنبطون قواعدها.
ومع مرور الزمن تحول النحو إلى باب من التكلف والتعقيد وكثرة الاختلافات والمذاهب النحوية، وبين هذا وذاك سجلت لنا كتب النحو واللغة والتاريخ مناظرات ومحاورات بين هؤلاء العلماء، ساهمت بشكل كبير في إثراء الدرس اللغوي والنحوي.
وفي هذا البحث حاولت أن أجمع بعض ما تفرّق في الكتب من هذه المناظرات والمحاورات، مركزا على ما ورد في كتاب "طبقات النحويين واللغويين" للزبيدي، ولذلك لأتعرف على البواعث الحقيقية لهذه المناظرات، فهل كانت خدمة للدرس والتعلم؟ أم مفاخرة ومكابرة وترفا علميا ابتُلي به أسلافنا آنذاك؟
Auteur(s) : بن زكورة العونية & سعيدي فاطمة الزهراء
Mots-clés : البيئة، الجباية البيئية،التنمية المستدامة، الاقتصاد الأخضر
ISSN : 2170-1776 | E-ISSN : 2600-6979 | Vol : 10, N° : 3, pp : 249-269
Résumé : مثل البيئة الوسط الذي يوفر كل المقومات اللازمة لحياة الإنسان، فقد عرف هذا المحيط العديد من التقلبات التي أثرت على مكوناته وكذا قدرته على توفير نفس الاحتياجات لأجيال المستقبل. وبناءا على هذا، جاءت هذه الدراسة لتسلط الضوء على آليات حماية البيئة في ظل التشريعات الجزائرية وما مدى تطبيقها واحترامها من جهة وكذا مساهمتها في حماية البيئة من جهة أخرى. فالجزائر كغيرها من الدول تبنت العديد من القوانين لحماية البيئة من مختلف الملوثات في إطار الجباية البيئية بهدف الحث على حماسة البيئة والتوجه نحو التوجه نحو التنمية المستدامة والاقتصاد الأخضر.
Auteur(s) : BELDJILALI gherici, MOHAMED CHERIF Ahmed, ZEGGA Kaddour
Mots-clés : Product manifolds Sasakian manifolds Kählerian manifolds
ISSN : 0138-4821 | Vol : 60, N° : 3, pp : 445-458
Résumé : The aim of this paper is to construct a 1-parameter family of Sasakian manifold starting from a single Sasakian manifold. Concrete examples are given.
Auteur(s) : Yasser Bouzid, Houria Siguerdidjane, M Zareb, Yasmina Bestaoui.
Mots-clés : Reference model IDA-PBC Autonomous UAV Internal energy Tracking control
ISSN : 2405-8963 | E-ISSN : 24058963 | Vol : 52, N° : 12, pp : 158-163
Résumé : This paper proposes a method to reach the equivalence between an IMC and a PI controller regardless of the model order. To this end, the key idea consists of using a specific IMC filter that exhibits a good level of robustness and further leads to get a structure of a PI controller whatever the order of the model is. The developed procedure constitutes the main contribution of this paper. To meet given set of specifications, the controller parameters are tuned through a straightforward analytic way using the dynamics of the tracking error. Furthermore, in order to evaluate the efficiency level of this procedure, an application to control an autonomous vehicle is described and the simulation results are shown to be satisfactory.
Auteur(s) : C Zelmat, T Fergoug, M Azayez, N Meddah, F Chater, H Boudjoras, Y Bouhadda
Vol : 293, pp : 111572
Résumé : Solubility and micelle formation of tetracaine-hydrochloride (TC,HCl) in aqueous solution has been studied by thermal conductivity. From thermal variations of the specific conductivity, parameters such as the critical micelle concentration, cmc, Krafft temperature, TK, and the variation of solubility with temperature were determined. The cmc's data analysis according to the mass action model has enabled to determine free energies of adsorption and of the micelles formation. A partial phase diagram of TC,HCl in water was also deduced and the micellization process discussed in light of enthalpy and entropy contributions.
Auteur(s) : H. Gherras, A. Yahiaoui, A. Hachemaoui, A. Belfedal, A. Dehbi, A. Zeinert
Mots-clés : Copolymer synthesis, solubility, poly(pyrrole-co-2-nitrocinnamaldehyde), pyrrole, 2-nitrocinnamaldehyde
Résumé : The use of conductive polymers as a substitute for metallic conductors and semiconductors has attracted much attention
in the literature. In particular, aromatic heterocyclic polymers constitute an important class since they possess chemical
and electrical stability in both the oxidized (doped) and neutral (undoped) state. A series of poly(pyrrole-co-2-nitrocinnamaldehyde)
were obtained via the condensation of pyrrole and 2-nitrocinnamaldehyde in chloroform using acid
exchanged montmorillonite clay called maghnite-Hþ as an efficient catalyst. The conjugated copolymer was characterized
using proton nuclear magnetic resonance, ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, and
scanning electron microscopy.
Auteur(s) : Ahmed Bouteffahaa,*, Abdelber Bendaoudb, Abdeldjalil Reguigb, Lucien Dascalescu
Mots-clés : Electrostatic processes Corona Current-voltage characteristics Current density Electric field Grid
ISSN : 0304-3886 | Vol : 101, N° : C, pp : 103367
Résumé : The triode-type electrode system is frequently employed for accurately controlling the corona charging of in-
sulating materials. The primarily aim of this paper is to characterize the effects of grid geometry of the triode-
type corona electrode system by current-voltage and current density distribution measurements. The ionizing
element of the electrode system is a thin Tungsten wire (diameter: 200 μm) attached to a cylinder (diameter:
26 mm) and distanced at 34 mm from its axis. The wire-cylinder assembly is a “dual” electrode, facing a grid
electrode, connected to a well-defined potential, and a grounded plate electrode. The geometry of the grid has a
very significant influence on the current-voltage characteristics of the triode system, on the corona onset voltage
value and on the repartition of the current density. The experimental results obtained for different geometries of
the grid electrode system are interpreted in order to make some recommendations regarding its design.
Auteur(s) : Beldjilali gherici
Mots-clés : Almost contact metric manifolds, Global basis.
ISSN : 2636-7467 | Vol : 2, N° : 2, pp : 175-186
Résumé : In this paper, starting from only a global basis of vector fields, we construct a
class of almost contact metric manifolds and we give concrete example. Next, we study some
essential types belonging to this class on dimension 3 and we construct several examples.
Auteur(s) : Salah Eddine Sari Hassoun, Mohammed Mékidiche, Mohammed Seghir Guellil
ISSN : 2651-396X | Vol : 14, N° : 29, pp : 199 - 223
Auteur(s) : F.Z.Kouidri
Mots-clés : Nanocomposites. Polymer-SiC. Optical properties. Electrochemical properties
ISSN : 0022-2860 | Vol : 1188, pp : 121-128
Résumé : Hybridization of nanomaterials constitutes an interesting approach to boost and develop novel properties and applications. In this work, different polyaniline (PANI)-derived polymer-SiC nanocomposites have been successfully synthesized by facile surface-initiated polymerization of aniline (ANI) and/or 4-Anisidine (4ANS) on HCl-functionalized SiC. The obtained materials were characterized by different analytical techniques as well as solubility, conductivity and electrochemical tests. The effect of the nature and combination of the substituents in the polymer was analyzed. XRD; thermogravimetry; and vibrational FTIR spectroscopy revealed effective polymerization and interaction between the polymers and the SiC nanoparticles to form PANI-SiC, poly(ANI-co-4ANS)-SiC and P4ANS-SiC nanocomposites. The presence of electron-donating (para) -OCH3 substituents was found to hinder this interaction and/or to retard the polymerization, decreasing the content and crystallinity of the polymer in the nanocomposite. However, the dispersibility of the nanocomposites in different solvents greatly increased, and the electroactive and optical properties were affected. As a result, the poly(ANI-co-4ANS)-SiC nanocomposite exhibits higher dispersibility, lower band gap, similar conductivity and richer electroactivity than PANI-SiC, and an intermediate polymerization yield. Then, engineering the substituents of polymer chains is demonstrated to be an efficient approach to tailor the properties of (PANI)-derived polymer-SiC nanocomposites.
Auteur(s) : Redouane Ayad, Wahid Nouibat, Mehdi Zareb, Yasmina Bestaoui Sebanne
Mots-clés : VTOL-UAV Fractional-order control Attitude control Modified Black–Nichols FOPID Quadrotor
ISSN : 2228-6179 | E-ISSN : 2364-1827 | Vol : 43, N° : 1, pp : 349-360
Résumé : This article presents a new design of fractional order ???????????? ????????
, for the full control of quadrotor (attitude and position)using a modified Black–Nichols method. First, we use single-input–single-output approach to design fractional-order ???????????? ???????? controllers for each position and attitude component. After that, we employ the same ???????????? ???????? controllers in the multiple-input–multiple-output model of quadrotor to test their performance. It is shown that we can improve the robustness and performance of the control significantly. Fractional-order modeling and control toolbox is used with Simulink model of quadrotor to prove and validate the performance of our controllers considering several scenarios.
Auteur(s) : Z. M'hamed ; K. Ali
Mots-clés : الشراكة قطاع عام - قطاع خاص ; التنمية ; الجزائر
E-ISSN : 2600-6383 | Vol : 8, N° : 1, pp : 122-133
Résumé : عتمـدت الحكومـة الجزائريـة في السـنوات الأخـيرة مبـادرات كبـيرة و متعـددة هتـدف إلى تشـجيع الشـراكة بـين القطـاعين العـام والخـاص.
فحسب العديد من الخبراء و المحللين، لا تزال هذه الحملة بدائية كو�ا لم تساهم إلى حد كبير للمساعدة من حيث النتائج لتصبح أداة
لتحسين وترشيد الإنفاق العام لاسيما اشكالية الإطار القانوني و وضوحه للمتعاملين الاقتصاديين. الغرض من هـذه الورقـة هـو تحليـل
و قراءة لهاته المبادرة الى جانب دراسة فرص تفعيلها و تحقيقها للتنمية الاقتصادية المستدامة لتجنب تكرار الأخطاء الماضية مع المقارنة
ابلتجارب الدولية و على الخصوص للدول الشقيقة كالمغرب و تونس.
Auteur(s) : Samir Ghouali,Mohammed Feham, Rachid Merzougui
Mots-clés : MSAN, AX MA5600T, C300M, NGN
ISSN : 2080-2242 | Vol : 11, N° : 02, pp : 32-34
Résumé : The evolution of an existing network to the new structure will require a phased migration strategy aimed at minimising capital expenditure during the transition phase, while reaping the benefits early on. Any action taken during this transition step should simplify the network's evolution to the NGN packet-switched architecture. This paper presents the development of PSTN networks into NGN Optical Fiber, its configuration and implementation of Smart AX MA5600T HUAWEI and C300M ZTE Shelfs MSANs solutions.
Mots-clés : المؤسسة العمومية-المرفق العام- العون الاقتصادي
E-ISSN : 2616-6526 | Vol : 16, N° : 01,
Résumé : تسعى الجزائر كدولة يعيش اقتصادها مرحلته الانتقالية ، إيجاد حلول وسط تمكّنها من تفعيل المبادئ الأساسية لاقتصاد السوق ،بعد ضبط الآليات التي تكرّس الدور التنظيمي و الرقابي للدولة في المجال الإقتصادي. تعتبر المؤسسة العمومية بمفاهيمها المختلفة أحد أهمّ صور تدخل الدولة في المجال الإقتصادي. ترتبط دراسة المؤسسة العامة من الناحية القانونية ارتباطا و ثيقا بالنظرية التقليدية للمرفق العام و القانون الإداري ، لذلك فمن البديهي أن يؤدي تحوّل هذه النظرية – تحديثها – إلى تحوّل في الطبيعة القانونية للمؤسسة العامة و في طبيعة الوظائف التي تؤديها و التي ترتبط في جزء منها بإدارة المرافق العامة الإقتصادية . و من هذا المنطلق جاءت إشكالية الورقة المقدمة، للبحث في مدى ملائمة الإطار القانوني للمؤسسة العمومية الإقتصادية تحديدا لمبادئ و قواعد اقتصاد السوق و للآليات المختلفة التي تدار بها المرافق العامة الإقتصادية .
Abstract:
As a country whose economy is in transition, Algeria seeks to find solutions that help it to activate the basic principles of the market economy, without ignoring its significant role as a joint economic participant, after the organization of the mechanisms that devote the regulatory role of the state in the economic sector and the public institution in its different concepts, the role of the intervening participant and the officer emerge. The public institution is adopted by Algeria as well as other countries, in order to avoid misadministration and administrative routine, as it is considered a tool of economic planning. In this sense, the problematic presented this paper was to examine the appropriateness of the legal framework of the public economic institution specifically to the principles and rules of the market economy and to the different mechanisms in which the economic utilities are managed
Mots-clés : الحماية الإجتماعية - هياكل الضمان الإجتماعي - - مبدأ التوحيد- النظام الإجباري- الأنظمة التكميلية
E-ISSN : 2588-2384 | Vol : 32, N° : 03, pp : 562-589
Résumé : يعتبر الحق في الضمان الاجتماعي من الحقوق التي كرّستها دساتير مختلف الدول ،حيث إنبثق هذا التكريس من المواثيق والإعلانات الدولية المختلفة لاسيما المادة 22 من الإعلان العالمي لحقوق الإنسان، و التي نصت على أن:" كل شخص باعتباره عضوًا في المجتمع، له الحق في الضمان الاجتماعي " و إذا كان الإعتراف بالضمان الاجتماعي كنظام كامل متكامل هو القاسم المشترك لمختلف الدول على إختلاف أنظمتها السياسية و توجّهاتها الإقتصادية ، إلا أن الإختلاف يكمن في طريقة تجسيده و الهيئات المشرفة على تنفيذه و طريقة تمويله و من ثمة كيفية توزيع مداخيله، أما عن المخاطر التي يغطيها فهي لا تخرج عن تطبيق مقتضيات الإتفاقية الدولية رقم 102.
تهدف الورقة العلمية المقدمة إلى إجراء دراسة مقارنة حول كيفية تطوّر تنظيم أنظمة الضمان الإجتماعي في كل من الجزائر والمغرب ، بغية معرفة طبيعة منظومة الضمان الاجتماعي في كل دولة و العوامل التي ساهمت في تحديدها بالتبعية ،كما تقتصر الدراسة على الجزائر و المغرب لتباين و إختلاف أنظمة الضمان الاجتماعي المطبقة في كل منهما.
Abstract:
The right to social security is one of the rights enshrined in the constitutions of the different States. This commitment stems from various international conventions and declarations, in particular article 22 of the Universal Declaration of Human Rights, which states: "Everyone, as a member of society, has the right to social security and is entitled to realization,..". If the recognition of social security as a complete integrated system is the common denominator of different states on the difference of their political systems and economic orientations, this difference lies in the manner of its embodiment and the bodies supervising its implementation and the manner of financing it and it is how to allocate its income, and the risks covered by it does not go to the application of the provisions of Convention no. 102.
The paper aims to conduct a comparative study on how the organization of social security systems in Algeria and Morocco has evolved in order to know the nature of the social security system in each state and the factors that contributed to its subsequent identification, as the study on Algeria and Morocco are limited to security systems variation and difference social aspects of each
Auteur(s) : M. DEBBAL M. BOUREGAA H. CHIKH-BLED M. CHIKH-BLED M. OUADAH
Mots-clés : optoelectronics, photonic fiber, sensor, numerical simulation, optical fiber, chromatic dispersion
ISSN : 2191-6322 | Vol : 40, pp : 1-4
Résumé : This paper describes study of photonic crystal fiber (PCF) in order to study the influence of temperature on the chromatic dispersion; these types of fibers are based on commercial structures, but air holes will be infiltrated with water. Using finite domain-beam propagation method, it is shown that the zero dispersion wavelength can be shifted from 1.058753 to 1.271767 µm, a shift
of 213 nm. At 50 °C, a shift of 169 nm.
Auteur(s) : Beloufa Abbès, Benaoumeur Bakhti, Driss Bouguenna, Mohammed Reda Chellali
Mots-clés : Half-Heusler, ab initio, Electronic, Magnetic, Mechanic properties
ISSN : 0921-4526 | E-ISSN : 1873-2135 | Vol : 563, N° : 15, pp : 50–55
Résumé : The structural, electronic, magnetic and mechanical properties of the ternary CrFeZ half-Heusler compounds (with Z = Si, Sn, Ge) have been determined ab initio using a full-potential linearized muffin tin orbital approach. Equilibrium properties such as lattice constant, bulk modulus and its pressure derivative are calculated. Spin-orbit interaction effect in the electronic structure and Fermi levels are revealed. The majority-spin electrons are found to be metallic in nature, while the minority-spin electrons are found to be semiconducting electronic band-structure. It is shown that calculated band structures, density of states, magnetic moments, and elastic constants of these alloys agree well with available with theoretical and experimental data. In addition, the investigated compounds are found to be mechanical stable. Our findings predict new properties, as-yet unreported elastic parameters in the C1b structure, and thus may be realized under ideal experimental circumstances, which make them potential candidates for future spintronic applications.
Auteur(s) : M. Zareb, W. Nouibat, Y. Bestaoui, R. Ayad, Y. Bouzid
Mots-clés : Mini-UAV Fuzzy control Autopilot Genetic algorithms
ISSN : 2228-6179 | E-ISSN : 2364-1827 | pp : 1-29
Résumé : This paper presents an off-line design strategy of an intelligent 3D autopilot of Micro-UAV Quadrotor. It consists of hybridization between two fuzzy controllers for the x and y motions and four PID classical controllers for the attitude/altitude motions. Genetic algorithms are used to adapt and optimize the value of the six controllers' parameters to achieve the best performance and decrease the consumed energy. Also, in order to ensure the global optimum control parameters, genetic algorithm named Bi-GA is used to automatically configure the two GAs using for the tuning process. This design strategy can be used to different types of Quadrotor (with cross or X configuration). Initially, in order to get the controller parameters, simulation tests are made on a commercial Quadrotor named AR.Drone V2. Finally, these parameters values are tested in an experiment using the robot operating system. The results of these experimentations confirm the effectiveness of using genetic algorithms in the design of intelligent PID autopilot.
Auteur(s) : بن أمينة مصطفى
Mots-clés : العلامة. التقليد ، الردع، الحجز. الوصف
Vol : 2, N° : 4, pp : 44-53
Résumé : يسعى المشرع الجزائري في أحكام الأمر رقم 03-06 المتعلق بالعلامات إلى توفير أقصى درجات الحماية القانونية للعلامات ويظهر هذا في تجريمه لفعل تقليد العلامة و استعمالها في مجال المنافسة دون إذن أو ترخيص من مالكها ، إضافة إلى تخصيص مجموعة من الإجراءات التحفظية التي تسبق أو تتزامن مع دعوى الموضوع.
إن الاجراءات التحفظية التي جاء بها المشرع الجزائري في قانون العلامات تسعى عموما لوقف عملية التقليد و تقليص حجم الضرر الذي يصيب مالك العلامة ، كما أنها تمثل تعاملا تشريعيا سريعا مع ظاهرة التقليد التي أصبحت صورها تتطور بشكل متسارع .
The Algerian legislator seeks the provisions of Order No. 03-06 on marks to provide the maximum legal protection for marks. This is manifested in the criminalization of the trademark tradition and its use in the field of competition without the authorization or authorization of the owner, in addition to the allocation of a set of precautionary measures preceding or coinciding The precautionary measures introduced by the Algerian legislator in the Trademark Law generally seek to stop the process of imitation and reduce the scale of damage to the owner of the mark, and represent a quick legislative deal with the phenomenon of tradition, whose images are rapidly evolving
Auteur(s) : MECHEROUR, M. E. A., & HACINI, I.
Mots-clés : Fonction RH, empowerment, marketing RH, innovation organisationnelle
ISSN : 2028-5175 | Vol : 1, N° : 19, pp : 368-388
Résumé : This study aims to highlight the contribution of the modern HRM practices such as empowerment and HR marketing to the actors' innovative behaviors. The study is conducted in Algeria Telecom Company, Unit of mascara. In the context of the stimulation of innovation following to “liberalize the creativity that’s in you”, the company has adopted several organizational changes in different fields such as the structure and policies. The results revealed that there is positive impact of empowerment and HR marketing on organizational innovation in Algeria Telecom.
Auteur(s) : K. Yamani
Mots-clés : Pyrrole N-Methylpyrrole Zirconium(IV) oxide Nanocomposites Electrochemical properties
ISSN : 1388-6150 | Vol : 135, pp : 2089-2100
Résumé : New polypyrrole (PPy)-derived polymer/ZrO2 nanocomposite materials are prepared by single-step oxidative polymerization of pyrrole (Py) and/or N-methylpyrrole (mPy) in the presence of HCl-functionalized ZrO2 nanoparticles and ammonium persulfate. The physicochemical features of the PPy–ZrO2, poly(Py-co-mPy)–ZrO2 and PmPy–ZrO2 hybrids were analyzed by XPS, FTIR, XRD and UV–Vis techniques. To explore the advantages of these nanocomposites for potential applications, their thermal, conductive and electrochemical properties were investigated. The characterization reveals that a chemical bonding, based on electrostatic interactions, is established between the polymers and the ZrO2 nanoparticles. Interestingly, it is found that the growth of polymer on the surface of Cl-functionalized ZrO2 becomes more significant as the Py moiety (–NH– species) content in the polymer increases. The thermal stability and conductivity of the polymers increase by hybridization with the ZrO2 nanoparticles. This is assigned to the affective interaction of the polymers with the ZrO2 nanoparticles. Particularly, the resulting nanocomposites keep high conductivities, ranging between 0.323 and 0.929 S cm−1. Finally, voltammetric characterization shows that the PPy–ZrO2 and poly(Py-co-mPy)–ZrO2 nanocomposites are electroactive, thus demonstrating their capability for electrochemical applications. These results highlight the great influence of the nanoparticle interface and the nature of monomer on the nanocomposite formation and properties.
Auteur(s) : B. Mohamed B. Mohammed
Mots-clés : GJMS operators, critical sobolev exposent, nodal solutions
ISSN : 17476933, 17476941 | Vol : 64, N° : 12, pp : 2105-2116
Résumé : In this paper, we investigate the existence of nodal solutions to elliptic problems involving the GJMS operators on Riemannian manifolds with boundary.
Auteur(s) : BELDJILALI gherici
Mots-clés : Almost Golden structure integrability G-Golden manifold
ISSN : 1660-5454 | E-ISSN : 1660-5446 |
Résumé : In this paper, we introduce a new class of almost Golden Riemannian manifolds and we construct a concrete example. Then, we are particularly interested in two more special types where we will study their fundamental properties and we present many examples which justify their study.
Auteur(s) : Mohamed A MEDEBBER, Abderrahmane AISSA, Mohamed El Amine SLIMANI and Noureddine Retiel
Mots-clés : Computational fluid mechanics; Natural Convection; Nanofluid; Magnetic Field; Finite Volume Method; Cylindrical coordinate, Partially Annular; Average Nusselt Number.
ISSN : 1662-9507 | Vol : 392, pp : 123-137
Résumé : The two dimensional study of natural convection in vertical cylindrical annular enclosure
filled with Cu-water nanofluid under magnetic fields is numerically analyzed. The vertical walls are
maintained at different uniform hot and cold temperatures, TH and TC, respectively. The top and
bottom walls of the enclosure are thermally insulated. The governing equations are solved
numerically by using a finite volume method. The coupling between the continuity and momentum
equations is effected using the SIMPLER algorithm. Numerical analysis has been carried out for a
wide range of Rayleigh number (103 ≤Ra≤106), Hartmann number (1 ≤Ha≤100) and nanoparticles
volume fraction (0 ≤ϕ≤0.08). The influence of theses physical parameters on the streamlines,
isotherms and average Nusselt has been numerically investigated.
Auteur(s) : Mouffoki Abderrahmane, Aicha Bessaim, Houari Mohammed Sid Ahmed, Abdelhakim Kaci, Tounsi Abdelouahed, El Abbas Adda Bedia
Mots-clés : FG nanobeam, vibration, thermal loading, shear deformation beam theory
ISSN : 2515-0464 | E-ISSN : 2515-0472 | Vol : 2, N° : 1, pp : 54-62
Résumé : In this article, thermo vibration analysis of functionally graded (FG) nanobeams subjected to linear and uniform temperature distribution is studied. The structure is modelled by new efficient shear beam theory considering the effect of shear deformation without shear correction factor. The mentioned theory satisfies the zero boundary traction conditions on the beam surfaces and can be used for transverse shear strains trigonometric distribution. Material properties of the nanostructure are assumed temperature-dependent and FG based on the distribution of power law. The influence of size scale is captured utilising Eringen theory of non-local elasticity. Based on the present theory, the motion equations are obtained using principle of Hamilton. It is found that the applied theory is very simple and leads to accurate results for thermo vibration analysis of FG nanobeams.
Auteur(s) : Zine El Abidine Elmagroud
Mots-clés : Internet Addiction. Students. Secondary school
ISSN : 2304-3717 | E-ISSN : 2312-8003 | N° : 43, pp : 499-508
Résumé : The present study aim at identifying the level of Internet addiction among Secondary School. And see if there are differences in the level of Internet addiction to students depending on the gender variable. residence and educational level.The sample consisted of (109) Students.The researcher uses Internet addiction scale. The results of this study show There is a moderate level of Internet addiction among secondary school students.It also shows There were no differences between males and females in internet addiction and Specialization.
Auteur(s) : Z. M'hamed ; B. Brahim ; L. Lakhdar
Mots-clés : Bien-être, Ouverture, croissance, MENA
E-ISSN : 2602-6694 | Vol : 7, N° : 1, pp : 105-113
Résumé : Depuis les années 80, nombreux pays en développement ont vu leur revenu individuel décliner,
cependant que certains autres, en nombre non négligeable, ont réussi à mettre à leur actif une
croissance modeste. Cette croissance économique lente, sinon nulle, a poussé ces pays d’être
engager en coopération avec les institutions internationales (FMI, Banque Mondiale) dans des
programmes d’ajustement structurel. Notre question est de savoir si l’ouverture sur l’extérieur et la
croissance économique auront-ils une incidence sur leur bien-être économique et social ? Pour ce
faire, nous essayerons d’examiner, dans le cadre d’un modèle de données de panel, l’influence de la
croissance via l’ouverture sur le bien-être économique à partir d'un échantillon pour certains pays
arabes (Algérie, Egypte, Jordanie, Maroc et Tunisie), couvrant la période 1980 à 2016.
Auteur(s) : B. Bouderbala, Z. Souidi, A. Hamimed, B. Bouamar
Mots-clés : Rainfall erosivity, Erosion, Annual rainfall, Macta
ISSN : 1808-0936 | Vol : 71, N° : 1, pp : 274-294
Résumé : The aim of the present study is to estimate rainfall erosivity in the Macta watershed of western Algeria. Mapping using GIS (geographical information system) allowed better visualization of the erosivity. Five indices of erosivity were tested on a rainfall series of 42 stations over a period of 41 years. The indices used were the Arnoldus index, the Arnoldus modified Fournier index (MFI), the Rango-Arnoldus index, the Leprun index and the Val et al. index. Rainfall of between 300 and 400 mm occurs in 24 stations (57% of the watershed) where the respective values of the Arnoldus, MFI and Rango-Arnoldus erosivity range from 86.54 to 123.93 MJ Mw/ha.year, 47.47 to 75.33 and 16.11 to 36.13, respectively. Monthly rainfall variability has an important role in the concentration of erosivity. Erosion values (MFI) at the watershed range from 19.22 to 126.78, which indicates a low erosivity potential. Rainfall of less than 300 mm recorded in 15 rain gauges (36%) has respective erosivity values ranging from 39.78 MJ Mw / ha.year, 19.22 and 3.34 to 109.73, 50.27 and 17.80. The erosivity index depends not just on the annual rainfall but also on the intra-annual rainfall pattern. The ratio of the MFI index to the Rango-Arnoldus R index will be closer to unity when rainfall is higher. The lower the rainfall, the more the ratio increases in favour of MFI index. The same indices are very close when the annual rainfall reaches and exceeds 500 mm. Our study has shown the importance of inter-annual variability and its influence on rainfall erosivity. The same index of erosivity can have different values for the same amount of annual rainfall, which means that it is the inter-annual variability of rainfall that leads to a high erosivity index. The method of calculating erosivity described by Paez proved effective, as it overcomes the constraint related to the unavailability of rainfall intensity data, especially in semi-arid areas. The present study could serve as a strategic support for socio-environmental decisions and could also complement any study, taking into account the different factors of water erosion. Our results can thus be taken as extra support to any study and decision on hydro-environmental development within the Macta watershed.
Auteur(s) : Dahou,K., Hacini, I & J Burgoyne
Mots-clés : Knowledge management, organizational learning,
ISSN : 1366-5626 | Vol : 31, N° : 3, pp : 2-16
Résumé : Purpose Organizational learning (OL) represents the real value and the heart of strategic management, the focal point to keep track of international development. This paper aims to investigate the effect of knowledge management (KM) on the development of OL capability (OLC) in international hotels installed in Algeria. Design/methodology/approach This deductive descriptive case study research examines the impact of KM, using knowledge conversion process (KCP) on the development of OLC. In all, 70 expatriates were targeted to respond to questionnaires, while only 47 were valid for analysis. Multiple regression analysis is used to analyze the influential processes on OLC. Findings The socialization, externalization and internalization have a direct positive significant effect on the development of OLC. Socialization is the major influencing factor. However, the combination has no effect on OLC. In sum, KM has an impact on the development of OLC in international hotels in Algeria. Practical implications Exhibiting the strong interdependency between KM and OL, expatriates emphasize on KM as the learning facilitator. The international hotels keen to realize KM as major process to build OLC. Socialization and internalization reinforce learning by providing primordial sophisticated tacit knowledge. Externalization generates expertise and strategic knowledge. Originality/value First, the research confirms the effect of KM process using KPC on OLC, stimulating learning at all levels; especially, in a developing Arab country, emphasizing the research’s theoretical contribution. The research is of high contribution, first of a kind in exploring the development of OLC in international hotels in the Algerian context; it is a newly emergent market, in its infancy stage, and an alternative that Algeria tries to boost to steer away from petroleum dependency.
Auteur(s) : Mohammed Seghir Guellil, Oussama KHEDIR, Assia Brahimi
ISSN : 2588-2503 | Vol : 3, N° : 1, pp : 01-19
Auteur(s) : Z. M'hamed ; A. Mokhtar
Mots-clés : التعاون ; التجارة الخارجية ; غاز طبيعي ; الجزائر ; الاتحاد الأروبي
E-ISSN : 2661-779X | Vol : 3, N° : 1, pp : 199-210
Résumé : تتناول هذه الورقة دراسة لاتفاقية الشراكة المبرمة والممضية بين الحكومة الجزائرية والاتحاد الأوروبي في أبريل 2002. نهيك عن هدف توسيع اطار تجاري محض كإنشاء منطقة تبادل حر في غضون عام 2021، بدا من المثير للاهتمام أن نحلل في السياق الحالي لتراجع أسعار النفط، منذ صائفة 2014، لآفاق الاقتصاد الجزائري من خلال هذه الاتفاقات المتعلقة بالتعاون في مجال الطاقة، حيث أن الجزائر تمثل سند مهم للطاقة بالنسبة للاتحاد الأوروبي من خلال شبكات النفط والغاز والكهرباء، مع قربها الجغرافي من أوروبا، الى جانب تاريخهما المشترك و الذي يمتد الى القرون الوسطى.
Auteur(s) : I. F.Bouguenna, A.Azaiz, A. Tahour
Mots-clés : Electric vehicleDynamicPMSMNeuro-fuzzy sliding mode controlExtended state observer ESO
ISSN : 0360-5442 | Vol : 169, N° : 169, pp : 1054-1063
Résumé : The choice of the control techniques has a positive impact on the traction chain particularly disturbance rejection ability and the energy management in the electric vehicle (electric motor, inverter, transmission, ect.). In this paper, a robust neuro-fuzzy-sliding mode control (RNFSMC) with extended state observer (ESO) technique is applied on the traction chain of the electric vehicle (Permanent magnet synchronous motor PMSM, Inverter, Transmission). However, most of the existing strategies of control that are applied on the traction chain lead to chattering phenomena, reducing the electric motor performance and disturbance rejection ability without forgetting the bad energy management on board the electric vehicle. To further enhance the performance of the traction chain, a hybrid control scheme is used to severally decrease the chattering phenomena in the PMSM electric motor and evolve the disturbance rejection ability which employs two types of controllers: Neuro-fuzzy sliding mode control on the direct current loop and ESO controller on both speed, and quadrature current loops taking into account the dynamic of the vehicle. Simulations by Matlab/Simulink are used to indicate the validity of the planed scheme on the closed-loop system. The simulation results show the effectiveness of the proposed control strategy with desired tracking accuracy.
Auteur(s) : I.Khelifa
Mots-clés : Conjugated polymer. Poly(orthophenylenediamine). Modifed-clay. Electrochemical properties
ISSN : 0022-2860 | Vol : 1178, pp : 327-332
Résumé : This work describes the synthesis and characterization of new poly(o-phenylenediamine (PoPD)/modified-clay nanocomposite materials. For the synthesis, the raw clay (named as Mag) used in this study was from Maghnia (west Algeria), (Mag) clay was ion-exchanged with cobalt(II) sulfate hydrate and copper sulfate. The modified-clays were then dispersed in a oPD monomer-containing acidic solution to carry out in-situ intercalative oxidative polymerization by ammonium persulfate. XRF and XRD characterization reveal the success of ion-exchange to form highly intercalated Mag-Co and Mag-Cu clays. After polymerization, the disappearance of the interlayer-spacing diffraction peak for the PoPD-Mag-Cu and PoPD-Mag-Co nanocomposites points out fully exfoliation of the clay structure. The formation of intercalated PoPD into modified-clay nanocomposites was confirmed by XRD, TEM, TG analysis, FTIR spectroscopy and UV–vis studies. The nanocomposites show optical properties and the redox processes observed by cyclic voltammetry indicate that the reported polymerization into modified-clays leads to electroactive hybrid materials. All these properties make these polymer/clay nanocomposites attractive materials for multiple applications.
Auteur(s) : H. Soltani
Mots-clés : Nanocomposites. Polymer-SiC. Optical properties. Electrochemical properties
ISSN : 1574-1443 | Vol : 29, pp : 841-850
Résumé : In this study, polyaniline/Clay nanomaterials (PANI/Clay) was synthesized through one-step method and used as an adsorbent to remove Cu(II) ions from aqueous solution. The PANI/Clay was characterized using X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, cyclic voltammograms and physical adsorption of gases. Adsorption parameters such as contact time, pH value, and initial metal ion concentration were investigated. The results revealed that PANI/Clay exhibits a much higher adsorption capacity than the natural clay; the attractive adsorption capacity reached 22.77 mg/g with 0.05 g of 100 mg PANI/Clay at an initial pH solution of 6 and adsorption temperature of 25 °C. Moreover, the Langmuir model well describes the adsorption data with the maximum sorption capacity of 22.77 mg/g. Pseudo-second-order model can fit well the kinetic data obtained from batch Cu(II) removal experiments. The Cu(II) adsorption on PANI/Clay nanocomposite was mainly attributed to electrostatic interaction, donor–acceptor interaction and intermolecular interactions.
Auteur(s) : B. Sid Ahmed, B. Fouzia, A. Adda, G. Farid
Mots-clés : Salinity; olive tree; salt stress; proline; chlorophyll.
ISSN : 1112-9867 | E-ISSN : ******* | Vol : 11, N° : 1, pp : 525-538
Résumé : Salinity is a major problem directly affecting the ecological balance and the development of agriculture in the Mediterranean basin, particularly North Africa. This phenomenon is considered as the most important abiotic factor limiting crops growth and productivity, degrading and polluting soils in arid and semi-arid. In order to study the influence of salinity, on the physiological parameters and to assess the potential of adaptation of the olive tree in a saline environment, three parcels containing the Sigoise variety and subject to different degrees of salinity were selected: Parcel 1 (non-saline); Parcel 2 (saline); Parcel 3 (very saline). Under a saline constraint, the results showed two contrasting tendencies, an intense increase in the content of proline, sodium (Na+) and chlorophyll (b), while water content, potassium and chlorophyll (a) decreased strongly with increasing salinity.
Auteur(s) : Ahmed Bensari, El Bahri Ould Chikh, Benattou Bouchouicha, Malika Tirenifi
Mots-clés : Welding; Residual Stress; Energy Release Rate; Stress Intensity Factor.
ISSN : 19718993 | Vol : 47 , pp : 17-29
Résumé : To evaluate the integrity of a structure is to prove its ability to
perform its mechanical functions for all modes of loading, normal or
accidental, and throughout its life. In the context of the nuclear safety, for the
most important structures such as the tank or the primary circuit, the
presence of a degradation in these structures grouping several aspects, such as
cracks created during welding. We seek then, to show the mechanical
resistance for this defect mode. It also seeks to fit the mechanical resistance
of a structure in the presence of a crack when the defects have been detected
during an inspection. In this context, the fracture mechanics provides the
necessary tools to analyze cracked components. Its purpose is to establish a
fracture criterion to foreordain the loading margins in normal or accidental
operating conditions. Each type of rupture must be the subject of a specific
characterization
Auteur(s) : Hachellaf Kaddour, El Bahri Ould Chikh, Meddah Hadj Miloud, Lounis Abdellah
Mots-clés : Polymers; Tensile tests; FSW; Vickers hardness test
ISSN : 19718993 | Vol : 47 , pp : 459-467
Résumé : Welding is a technique of fusion joining the material involving
a process of inter-molecular diffusion adhesion. Polymer welding is an
assembly method among several known assembly techniques such as gluing.
This welding process applies to thermoplastics; they have the rheological or
softening characteristics during melting. This process is fast and controlled in
order to obtain a solid and durable mechanical connection on the series parts.
This study focuses on the weldability of high density polyethylene (HDPE)
using the friction stir welding technique. A parametric choice was made to
optimize the operating parameters namely the shape of the welding tool, the
speed of rotation and the speed of advance of the tool. Monotonic tensile
tests were used to compare the mechanical characteristics between a HDPE
test specimen and a specimen taken from an FSW weldment.
It emerges from this study that the FSW welding introduces a weakening of
the joints characterized by a clear decrease of the deformation at break.
Auteur(s) : M.Bouregaa, M.Chikh-Bled, M.Debbal, C.Ouadah, H.Chikh-Bled
ISSN : 2080-2242 | Vol : 10, N° : 04, pp : 121-123
Résumé : Many multiple access techniques have been proposed and demonstrated to provide flexible solutions for FTTH network configurations. The performance of this system suffers because of the correlation properties that contribute to a high level of Multiple Access Interference (MAI), low system capacity (users), and lower transmission rate. In this paper, we have proposed Optical CDMA (OCDMA) as a configuration solution for FTTH networks to improve the performance of this type of network.
Auteur(s) : صدار لحسن ،مزيان محمد
Mots-clés : هيئة التدريس ،معاير الجودة ،التعليم العالي ،الجامعة
ISSN : 2170-1822 | E-ISSN : 2600-6189 | Vol : ?????? ?????? , N° : ??? ??? ?????? 2018, pp : 333-364
Auteur(s) : Mohammed Seghir GUELLIL , Mostéfa BELMOKADDEM, Mohamed BENBOUZIANE
ISSN : 1886-516X | Vol : 26, pp : 71–83
Auteur(s) : B. Moulai Ali, El Bahri Ould Chikh, B. Bachir Bouiadjra
Mots-clés : Polyvinyl chloride, stress triaxiality, damage, tensile test
Vol : 61, N° : 3, pp : 1–11
Résumé : The polymers are known to be delicate to hydrostatic pressure. The impact of stress triaxiality proportion
on damage and cavitation has been shown in numerous investigations. This article proposes trial
examinations to control both the stress triaxiality proportion and the void distribution by microscopic observations
of surfaces from tensile tests. For that, the Gurson−Tvergaard−Needleman model was adjusted with
the assistance of a finite element code, by utilizing multi-scale trial information. At that point correlation
between both numerical and analytical models and experimental data was performed.
In addition, a better understanding of the time development of critical parameters, for example, the porosity
(volume change) and the stress triaxiality proportion (hydrostatic pressure), was featured.
Auteur(s) : منصوري مصطفى
Mots-clés : الاحتراق النفسي، الآستاذ، التعليم الثانوي
ISSN : 2253-0746 | E-ISSN : 2600-6472 | Vol : 7, N° : 1, pp : 160-171
Résumé : هدفت الدراسة إلى معرفة مستوى الاحتراق النفسي لدى أساتذة التعليم الثانوي، وكذا التعرف على الفروق في مستوى الشعور بالاحتراق النفسي تبعا لمتغير الجنس وسنوات الخبرة والحالة الاجتماعية لدى الآساتذة، جرت الدراسة بمدينة معسكر حيث تكونت عينة الد راسة من 160 أستاذ وأستاذة تم اختيارهم بطريقة عشوائية، طبق عليهم مقياس ماسلاش للاحتراق النفسي، وتمت المعالجة الإحصائية للبيانات ببرنامج الرزم الإحصائية للعلوم الاجتماعية وكشفت النتائج عن وجود مستوى مرتفع من الاحتراق النفسي لدى أساتذة التعليم الثانوي،كماأظهرت النتائج عدم وجود فروق ذات دالة إحصائية في درجة الاحتراق النفسي تبعا لمتغير الجنس، وسنوات الخبرة، والحالة الاجتماعية
Auteur(s) : BENMESMOUDI AALI
Mots-clés : Plagiarism, online plagiarism, offline plagiarism, self plagiarism, cheating in exams
ISSN : 2311-5181 | N° : 48, pp : 139-147
Résumé : In this paper we clarify the phenomenon of plagiarism which threatens the credibility of both the examination and the learning process
Auteur(s) : Djazia Bouderbala, Zahira Souidi, Frédéric Donze, Mohamed Chikhaoui, Laounia Nehal
Mots-clés : Erosion . GIS . Remote sensing . USLE . Fergougwatershed . North-Western Algeria
Vol : 11, N° : 23, pp : 744
Résumé : Fergoug watershed is subject to severe water erosion and land degradation that threaten agricultural sustainability for local
populations. Soil loss and degradation by water erosion were estimated using the universal soil loss equation (USLE). The spatial
distribution of soil losses was determined using the following parameters: the erosivity factor (R), obtained using climatic data
from 12 local stations over a period of 41 years; the land cover factor (C), obtained using LandSat-TM satellite imagery 7 and 8;
the erodibility factor (K), estimated from soil particle size analyses; and the topographic factor (LS), obtained from a digital
terrain model. The Fergoug watershed is characterized by complex topography, and the topographic factor reached a value of
14.29. The erodibility factor K ranged from 0.08 to 0.38, and high values were recorded for about 20% of the watershed. The
rainfall erosivity factor R ranged between 212.32 and 146.73 from east to west. The plant cover factor varied inter- and intraannually
from 2.24 in May 2000 to 0.06 in May 2015. As a result, soil losses varied from 0.35 to 617.66 tons per hectare per year
(t/ha/year) in a rainy year, and from 0.27 to 1188.92 t/ha/year in a dry year. The combined effects of the slope angle and the
vegetation cover were shown to play a major role in soil losses in this area.
Auteur(s) : K. Khaldi
Mots-clés : Adsorption. Isotherms. Quinmerac Diatomite activation
ISSN : 1068-3755 | Vol : 54, pp : 194-202.
Résumé : Algerian aluminosilicate mineral natural diatomite and its modified variant were applied to remove quinmerac (QM)—a week acid herbicide from aqueous solutions. Then samples were investigated by the transmission electron microscopy, X-ray diffraction analysis, X-ray fluorescence and physical adsorption of gases. The adsorption experiments were carried out at ambient temperature in baths at different pH and the results showed that the amount of adsorbed QM increased at a higher pH, reaching a maximum at pH 2.5. The Langmuir model provided the best correlation of the experimental data for adsorption equilibrium. It was found that the modified diatomite exhibits a slightly better efficiency in the removal of QM than natural diatomite; this is why it could be considered to be an alternative material for removing a specific pollutant from environment.
Auteur(s) : A. Belalia
Mots-clés : Conjugated polymer. Poly(orthophenylenediamine). Modifed-clay. Electrochemical properties
ISSN : 1560-0904 | Vol : 60, pp : 816-824
Résumé : PANI and PANI-SiO2 were prepared by chemical oxidative polymerization in acidic medium of hydrochloric acid (1 M) using ammonium persulfate as oxidant. The developed adsorbents were characterized using various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and physical adsorption of gases. To further explore the advantages of these materials for real applications, we investigated the electrochemical properties of these samples electrodes. The efficiency of PANI, SiO2 and PANI-SiO2 for the adsorptive removal of phenol (Ph) from aqueous solutions has been evaluated with respect of several experimental conditions. These latter has to do with the effect of contact time and the effect of pH. The experimental data were analyzed by the Langmuir and Freundlich isotherm models. The Langmuir isotherm fits the experimental data very well due to the homogeneous distribution of active sites onto adsorbents surface. The kinetics study revealed that adsorption of Ph onto three samples follows the pseudo-second order kinetic model.
Auteur(s) : Mohamed A. MEDEBBER, Belkacem OULD SAID, Noureddine RETIEL
Mots-clés : Free convection; Surface radiation; Finite Volume Method; Coordinate cylinder, Radiative Transfer Equation (RTE), Discrete Ordinates Method (DOM), Partially Annular caviy; Average Nusselt Number.
ISSN : 1662-9507 | Vol : 389, pp : 36-49
Résumé : Two dimensional combined free convection and thermal radiation in an annular region of
two concentric vertical cylinders filled with air (Pr=0.71) has been numerically investigated. The
steady-state continuity, Navier–Stokes and energy equations were carried out by the finite volume
method, and the Discrete Ordinates Method (DOM) was used to solve the radiative heat transfer
equation (RTE). The flow is considered to be laminar and the properties of air are assumed to be
constant except for the density variation for which the Boussinesq approximation is used.
Concerning the radiation exchange, we consider that the fluid (air) is transparent, so only the solid
surfaces contribute to the radiation exchange and assumed to be diffuse-gray. The computations are
performed for Rayleigh number (Ra) in the range 103≤Ra≤106 and for the surface emissivity (ε)
0≤ε≤1 while the radii ratio of the curvature (K) is kept equal to 2. The key parameters for this
analysis are considered as Rayleigh number (Ra), surface emissivity (ε). Results are reported in
terms of isotherms, streamlines and total average Nusselt numbers. The results showed that the
mean total Nusselt number increases monotonically with increasing Ra number and the surface
emissivity.
Auteur(s) : Abdallah, OULD CHIKH El Bahri, MEDDAH Hadj Miloud, GUERAICHE Larbi, HACHELLAF Kaddour
Mots-clés : Polymer PEHD; friction-stir spot welding FSSW; assemblage; welding parameters; tools geometries.
ISSN : 10120386 | Vol : 389, pp : 205-215
Résumé : This research paper aims at studying the friction stir spot welding (FSSW) some of
thermoplastic polymer materials (HDPE and HDPE-PMMA) using a specifal geometry tool without
a pin. The effect of the tool geometry on the welds static resistance was studied via several tool
shape, a flat shape below the tool, a shape with concavity angles ranging from 0° to 16°, a flange
shape of the sharp-edged tool, a chamfered flange shape and a rounded shape. This work is done to
increase the surface area of the weld and further to maximize the static strength of the friction stir
spot welding. Experimental tests have been carried out under various operational parameters such
as the tool rotation speed, tool plunge depth and dwell time. This later has been carried out to
highlight the effect of the tool’s geometry and the operational parameters of the welding on the
surface in virtue on static resistance of the friction stir spot welding of thermoplastic polymers.
Tests of lap-shear at speed of 5m/s have showed that the tool geometry plays a very important part.
This study shows that a FSSW welding tool with 4° concavity angle tool and a rounded flange
shape gives the best welding quality for the polymers studied.
Auteur(s) : I. F.Bouguenna, A.Azaiz, A. Tahour
Mots-clés : Electric vehicleDynamicPMSMNeuro-fuzzy sliding mode controlExtended state observer ESO
E-ISSN : 2267-1242 | Vol : 61, N° : 7,
Résumé : In this paper a neuro-fuzzy-sliding mode control (NFSMC) with extended state observer (ESO) technique; is designed to guarantee the traction of an electric vehicle with two distinct permanent magnet synchronous motor (PMSM). Each PMSM systems (source-convertermotor) are attached to an electronic differential (ED), in order to adjust the senses of direction of the vehicle, and sustain a stable speed by adapting the difference in velocity of each motor-wheel according to the direction in the case of a turn. Two types of controllers are employed by a hybrid control scheme to assure the control and the performance of the vehicle. This hybrid control scheme guarantees the stability of the vehicle by ED, reduces the chattering phenomena in the PMSM electric motor, and improves the disturbance rejection ability which employs tow types of controllers. The neuro-fuzzy sliding mode control on the direct current loop and ESO controller on the speed loop, and the quadratic current loop; taking into account the dynamic of the vehicle. Simulation runs under Matlab/Simulink to assess the efficiency, and strength of the recommended control method on the closed loop system.
Auteur(s) : Hacini, I, & Dahou, K
Mots-clés : Data Envelopment Analysis, Domestic banks, Effi ciency, Foreign banks
ISSN : 1366-5626 | Vol : 2, N° : 10, pp : 06–119
Résumé : The study investigates the differences in technical, pure technical, and scale efficiencies of domestic and foreign banks in Algeria over the period of 2000–2012. The study uses annual data of 10 foreign banks and 05 domestic banks operated in Algeria. The input-oriented Data Envelopment Analysis model is used to measure the banks’ efficiency score. In addition, a set of parametric and non-parametric tests are used for investigating the differences in efficiencybetween foreign and domestic banks. The findings reveal that the banks in Algeria could improve their technical efficiency by 23%. In addition, it seems that banks in Algeria suffer from the scale inefficiency. On the other hand, the foreign banks are more technically efficient than domestic banks. The superiority of foreign banks in technical efficiency is due to their superiority in the scale efficiency.
Auteur(s) : S.Daikh
Mots-clés : Nanocomposites. Aniline. Zinc oxide. Zinc chloride. Electrochemical properties
ISSN : 1068-3755 | Vol : 121, pp : 78-84
Résumé : An in-situ polymerization method has been employed to prepare HCl-doped polyaniline (PANI)/ZnO nanocomposites and (HClZnCl2) doped PANI/ZnO. Structural characteristics were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet spectroscopy (UV), thermogravimetric analysis (TGA) and Transmission Electron Micrographs (TEM). TGA results showed that the decomposition of the HCl doped PANI/ZnO nanocomposites was less than that of (HClZnCl2) doped PANI/ZnO nanocompositess. Conduction studies were done by using four-probe method. Electrical conductivity study shows an increase in the conductivity of the samples with the (HClZnCl2) doped) PANI/ZnO to 0.081 S cm−1. To further explore the advantages of these nanocomposites for real applications, we investigated the electrochemical properties of these samples electrodes, the (HClZnCl2-doped) PANI/ZnO nanocomposite presented much higher electrochemical response to (HCl-doped) PANI/ZnO and (ZnCl2-doped) PANI/ZnO nanocomposites.
Auteur(s) : بن زكورة العونية
Mots-clés : المؤ.ص.م، التنمية المستدامة، الأطراف ذات المصلحة ، أبعاد التنمية
ISSN : 9796- 2571 | E-ISSN : 5051 -2602 | Vol : 3, N° : 2, pp : 228-244
Résumé : تهدف دراستنا إلى التعرف على علاقة المؤسسات الصغيرة والمتوسطة بالتنمية المستدامة من خلال دراسة ميدانية على مجموعة من المؤسسات في ولاية معسكر. تعتبر التنمية المستدامة في الوقت الحالي تحدي أمام مسيري المؤسسات في ظل التوجه نحو الاقتصاد الأخضر، فهي مطالبة بمراعاة مصالح الأطراف الفاعلة في المجتمع بما فيها الدولة.
كشفت الدراسة عن انعدام العلاقة بين المؤسسة والتنمية المستدامة، فالمؤسسات تحترم وتطبق القوانين والتشريعات ، إلا أنهالا تهتم بمسؤوليتها اتجاه الأطراف ذات المصلحة من ناحية إشباع رغباتهم .فالتنمية المستدامة لا تمثل محور في الأهداف الإستراتيجية للمؤسسة أو حتى ضمن تطلعاتها المستقبلية.
L’objectif de notre étude est d’identifier la relation entre les petites et moyennes entreprises et le développement durable à travers l’étude appliquée sur un ensemble d’entreprises activant au niveau de la wilaya de Mascara. Le développement durable est, en ces temps, considéré comme un défi lancé au managers d’entreprise compte tenu de la tendance à l' économie verte, elles sont tenues de prendre en considération les intérêts des acteurs de la société, y compris l'Etat.
L'étude a permis de constater l'absence de la relation entre l’entreprise et le développement durable, les entreprises respectent et appliquent les lois et les règlements, mais elles ne tiennent pas compte de la responsabilité envers les parties prenantes en terme de satisfaction de leurs préférences. Le développement durable n’est pas au centre des objectifs stratégiques de l'organisation et même de leurs aspirations
Auteur(s) : Assia Hebri.
Mots-clés : L’énergie, le programme énergétique, L’efficacité énergétique, Les énergies renouvelables, L’Algérie.
Vol : ?????? 3,,, N° : ????? 5, pp : ?????? 350-369
Résumé : Cette étude décrit les deux scénarios proposés par l’ Observatoire Méditerranéen de l’énergie (OME) d’ici 2040 , pour la production et la consommation de l’énergie dans les pays de nord et sud méditerranéen , Elle décrit les deux scénarios proposés par l’ Observatoire Méditerranéen de l’énergie (OME) d’ici 2040 , pour la production et la consommation de l’énergie dans les pays de nord et sud méditerranéen , plus les tendances d’efficacité énergétique dans ses pays et donc préciser les points positifs et négatifs des politiques énergétiques utilisés par voie d’analyse, comparaison et de conclusion, ce qui nous permet de saisir un nombre très important des informations utiles à l’illustration des tendances futurs dans le domaine de l’énergie pour ces pays.
Auteur(s) : H. Gherras, A. Yahiaoui, A. Hachemaoui, A. Belfedal, A. Dehbi, A-H I. Mourad;
Mots-clés : proposed technique; Maghnite-H+ catalyst; conducting PPPM copolymer; pyrrole; pyrrole-2-carboxaldehyde
Vol : 39, N° : 09,
Résumé : In the current research, the proposed technique to synthesise poly {(2,5-diyl pyrrole) (2-pyrrolyl
methine)} (PPPM) copolymer by condensation of pyrrole and pyrrole-2- carboxaldehyde monomers catalyzed by
Maghnite-H+ is introduced. The protons are exchanged with Maghnite-H+, which is available in the form of a
montmorillonite silicate clay sheet. The effect of several parameters such as time and temperature of copolymerization,
[pyrrole]/[pyrrole-2-carboxaldehyde] molar ratio, amount of Maghnite-H+, and solvent on the produced poly
(2,5-diyl pyrrole-2- pyrrolyl methine) semiconductor copolymer material (yield%) was investigated.
Auteur(s) : Amina Meliani
Mots-clés : Biofilm, Chemotaxis , regulatory system
ISSN : 2210-4410 | E-ISSN : 2210-4429 | Vol : 31, pp : 1 - 25
Résumé : Chemotaxis in Pseudomonas species is one of the most diversified and
best-understood signal transduction network. Most strains possess one or two sets
of the chemotaxis genes. They have the ability to sense changes in the concentration
of chemicals in the environment and respond by altering their pattern of motility
using the two chemotaxis pathways. The flagella-mediated pathway and the
pili-mediated system are involved in bioremediation, pathogenesis and plant protection.
Although a large number of Pseudomonas species have chemotaxis abilities,
only seven species have had their chemotaxis abilities screened. P. aeruginosa
is now considered as a model organism for the study of chemotaxis systems. This
chapter reviews chemotaxis and biodegradation in Pseudomonas species.
Mots-clés : المراقبة الميدانية- المراقبة المحاسباتية- مراقب الضمان الإجتماعي – المؤمن له إجتماعيا-المكلف
ISSN : 1112-9751 | E-ISSN : 2253-0363 | Vol : 10 , N° : 03, pp : 270-302
Résumé : تقتضي ضرورة التطبيق السليم لتشريع الضمان الاجتماعي، ضمان المراقبة المستمرة لمختلف أحكامه ،حيث تعتبر المراقبة الإدارية في مجال الضمان الاجتماعي أهم الآليات التي تساهم في ضمان ديمومة المنظومة وتأديتها لمختلف وظائفها . تمحورت إشكالية الورقة البحثية حول البحث في حدود مساهمة المراقبة الإدارية في المحافظة على ديمومة منظومة الضمان الاجتماعي ، الإجابة التي إستدعت ضرورة التدقيق في ماهية المراقبة الإدارية، بغية حصر أهم أثارها بالتبعية بعد تحديد مضمونها و الفئات المشمولة بها
Abstract:
The need for proper application of the social security legislation, requires to ensure the continuous monitoring of the various provisions. Therefore, administrative control is considered in the area of social security the most important mechanisms that contribute to ensure the sustainability of the organization and performing its various functions.
Auteur(s) : F. Zahaf , R.Marouf, F.Ouadjenia, J. Schott
Mots-clés : Bentonite; Modified clay; Heavy metals; Adsorption kinetics
ISSN : 1944-3994 | E-ISSN : 1944-3986 | Vol : 131, pp : 282–290
Résumé : Clays intercalated with organic molecules and/or hydroxy-metal cations, also known as inorganic–
organic clays (IOCs), have attracted a great deal of attention among researchers in recent years.
In the present work, cetyltrimethyl ammonium bromide (CTMAB) and hydroxy-aluminum (Al13)
were selected to be used as intercalants in bentonite that was originally brought from the town of
Mostaganem (Algeria). The modified bentonite materials were used to adsorb three heavy metals,
namely Pb(II), Cr(III) and Cu(II). Some samples of B–Al and B–CTAB were prepared and characterized
using different techniques, like XRD, FTIR, and BET. The adsorption process was carried out
under various operational conditions by varying the temperature, initial concentration of metal
and contact time. The results obtained indicated a significant increase of the interlayer spacing after
intercalation with CTAB. The BET surface area also increased. The sequence of adsorption capacity
for the three metals was found to be like Cr3+ > Pb2+ > Cu2+. The adsorption kinetics could be very
well described using the pseudo-second order kinetic model. The Intra-Particle Diffusion (IPD)
model for sorption was also investigated and compared to other models; it was used to identify
the sorption mechanism. Several thermodynamic studies found out that the adsorption process is
endothermic and spontaneous in nature.
Auteur(s) : Malika ABBES, Abderrahmane HAMIMED, Aicha LAFRID, Habib MAHI, Laounia NEHAL
Mots-clés : drought, Northwestern Algeria, SPI, NDVI, linear regression, satellite imagery
ISSN : 0370-0798 | Vol : 25, pp : 85–113
Résumé : Over the last decades, Algeria has witnessed intense and persistent drought periods characterized
by a significant rainfall deficit. The Northwestern Algeria, such as the most south Mediterranean
regions, is marked by alternating wet and dry periods and mixing between Atlantic and Mediterranean
airs. In a climate context increasingly disturbed by anthropogenic activities, it is essential to analyze the
dry episodes at spatial and temporal scales. In order to understand this problem, this work aims to use the
potential of Landsat satellite imagery for monitoring drought conditions in the Cheliff watershed in the
northwestern Algeria. As known, the behavior of vegetation is strongly related to climate changes. On
this basis, a comparison of the variations in the standardized normalized difference vegetation index
(NDVI) and those of the drought indices calculated from meteorological data was implemented. In fact,
the rainfall series from fifty meteorological stations were analyzed. The standardized precipitation index
(SPI) was calculated for the years 1987, 2000, 2006, 2011 and 2015, corresponding to the acquisition
dates of Landsat images. Similarly, an extraction of the NDVI values was performed for each meteorological
station. The linear regression between SPI and NDVI showed a good correlation. Thus, the obtained
results enabled establishing a new drought index based essentially on satellite data. This index
represents the advantage for monitoring spatially the drought phenomena and can solve the problem of
climatic data lack.
Auteur(s) : Meriem Amina Zingla, Chiraz Latiri, Philippe Mulhem, Catherine Berrut, Yahya Slimani.
Mots-clés : Information Retrieval; Query Expansion; Microblog Information Retrieval; Tweets Search; Explicit Semantic Analysis; Tweet Contextualization; TREC 2011; INEX 2014; WIKIPEDIA; DBPEDIA; Association Rules.
Vol : 21, N° : 4, pp : 337-367
Auteur(s) : BELDJILALI gherici, BELKHELFA mohamed.
Mots-clés : Product manifolds, Trans-Sasakian structures, K¨ahlerian structures
ISSN : 1539-854X | Vol : 21, N° : 2, pp : 1-14
Résumé : In this paper we give a generalization of the doubly D-homothetically warped
metric introduced by Blair [4], and we study the construction of K¨ahlerian structure
on the product of two almost contact metric structures. It is shown that if one factor is
β-Kenmotsu, the other is β-Kenmotsu or α-Sasakian, and if one factor is cosymplectic,
the other is α-Sasakian, but the product of two α-Sasakian is never K¨ahlerian. Several
examples are discussed
Auteur(s) : Amina Houari, Wassim Ayadi, Sadok Ben Yahia
Mots-clés : Biclustering · Formal concept analysis · Data mining · Bioinformatics · DNA microarray data · Bond correlation measure
ISSN : 1868-8071 | Vol : 9, N° : 11, pp : 1879-1893
Résumé : Biclustering has been very relevant within the field of gene expression data analysis. In fact, its main thrust stands in its ability to identify groups of genes that behave in the same way under a subset of samples (conditions). However, the pioneering algorithms of the literature has shown some limits in terms of the quality of unveiled biclusters. In this paper, we introduce a new algorithm, called BiFCA+, for biclustering microarray data. BiFCA+ heavily relies on the mathematical background of the formal concept analysis, in order to extract the set of biclusters. In addition, the Bond correlation measure is of use to filter out the overlapping biclusters. The extensive experiments, carried out on real-life datasets, shed light on BiFCA+’s ability to identify statistically and biologically significant biclusters.
Auteur(s) : Amel BOUKHLIF, Ali MERDJI, Noureddine DELLA, El-Bahri OULD CHIKH, Osama MUKDADI and Rajshree HILLSTROM
Mots-clés : dental bridge, FE analysis study, supporting implants, bone, masticatory load, stress analysis
ISSN : 2296-9845 | Vol : 37, pp : 43-54
Résumé :
The number of supporting dental implants is an important criterion for the surgical
outcome of dental bridge fixation, which has considerable impact on biomechanical load transfer
characteristics. Excessive stress at the bone–implant interface by masticatory loading may result in
implant failure. The aim of this study was to evaluate the impact of the number of implants
supporting the dental bridge on stress in neighboring tissues around the implants. Results of the
study will provide useful information on appropriate surgical techniques for dental bridge fixation.
In this study, osseointegrated smooth cylindrical dental implants of same diameter and length were
numerically analyzed, using three-dimensional bone–implant models. The effect of the number of
supporting implants on biomechanical stability of dental bridge was examined, using two, three and
four supporting implants. All materials were assumed to be linearly elastic and isotropic.
Masticatory load was applied in coron-apical direction on the external part of dental bridge. Finite
Element (FE) analyses were run to solve for von Mises stress. Maximum von Mises stresses were
located in the cervical line of cortical bone around dental implants. Peak von Mises stress values
decreased with an increase in the number of implants that support the dental bridge. Results of this
study demonstrate the importance of using the correct number of supporting implants to for dental
bridge fixation.
Auteur(s) : Mohammed El Amine Senoussaoui , Mostefa Brahami, Issouf Fofana
Mots-clés : DGA, Power transformer, Diagnosis, Machine learning, Ensemble technique
ISSN : 1751-8687 | E-ISSN : 1751-8695 | Vol : 12, N° : 15, pp : 3673-3679
Résumé : Since the discovery of dissolved gas analysis (DGA), it is considered as a leading technique for the diagnosis of liquid insulated power equipment. However, accurate analysis results can only be achieved if the measured gases closely reflect the actual equipment condition to enable an appropriate interpretation of these gases. In general, conventional techniques such as the ratio method, key gases, and Duval triangle combined or not with artificial intelligence techniques such as machine-learning algorithms are used for DGA interpretation. Here, four well-known machine-learning algorithms are compared in terms of DGA fault classification – Bayes network, multilayer perceptron, k-nearest neighbour, and J48 decision tree. Moreover, the effect of applying ensemble methods such as boosting through the Adaboost algorithm and bootstrap aggregation (bagging) is analysed, and the performances of these algorithms are evaluated. The data for developing classification models was transformed into three forms, other than the raw data. The obtained results clearly presented the efficiency and stability of some algorithms such as the J48 tree and Bayes networks for DGA fault classification, in particular, when the data is appropriately pre-processed. Moreover, the performance of these algorithms was found to consistently improve by integrating the concepts of multiple models or ensemble methods.
Auteur(s) : Salem A Al-Jundi , Mohammed Seghir GUELLIL
ISSN : 1756-9869 | Vol : 15, N° : 4, pp : 524-540
Auteur(s) : Assia Hebri.
Mots-clés : L’énergie, le programme énergétique, L’efficacité énergétique, Les énergies renouvelables, L’Algérie.
Vol : ?????? 9, , N° : ????? 1, , pp : ?????? 351-362
Résumé : L’objectif principal de cette étude est de cibler quelques pratiques techniques et économiques utilisées dans le domaine énergétique, selon les capacités énergétiques de l’Algérie, elle s’appuie sur les indicateurs d’efficacité énergétique par grand secteur consommateur d’énergie. Pour maitriser la consommation énergétique et assurer le passage sein et rationnel au domaine des énergies renouvelables. On trouve ici que les piliers de ce passage sont divers et multiples, débutant de l’efficacité des politiques générale de l’énergie, passant par une stratégie seine et fiables pour les indicateurs énergétiques, arrivant au perspectives claires et lignes directrices des stratégies globales de productions et consommation de cette énergie. L’objectif de l’efficacité énergétique consiste à produire les mêmes biens ou services, mais en utilisant le moins d’énergie possible. Le programme algérien comporte des actions qui privilégient le recours aux formes d’énergie les mieux adaptées aux différents usages et nécessitant la modification des comportements et l’amélioration des équipements.
Auteur(s) : T.Aicha, B. Hamida, M.Boumediene
Mots-clés : zizyphus lotus- methanolic extract-
ISSN : 1112-9867 | Vol : 10, N° : (2), pp : 252-266
Résumé : The aim of this in vitro study was to assess the antibacterial effect of the methanolic extract obtained from the roots of Zizyphus lotus(communally Sedra) collected in Mascara on analysis which revealing 433,65μg EGA / mg dm ofcollected from the oral cavity (10 students) against bacteria responsible of oral pathologies, isolated from students aged from 20 to 28 years. Chemical qualitative analysis of this extract revealed the presence of polyphenols, flavonoids and tannins confirmed by a quantitative analysis polyphenols, 247,87μg EQ / mg dm of flavonoids and 167.05 μg ECT/ mg dm of tannins.microbiological analysis of samples bacterial groups (streptococci, staphylococci, lactobacilli and enterobacteria).Extract of Zizyphus lotus tested on agar medium and microdilution method showed an
important inhibition diameter of 40 mm respectively towards Lactobacillus sp.
Auteur(s) : عمري رشيد
Mots-clés : الطلاق التعسفي، التعسف، الطلاق، التليق ، الضرر، التعويض الضمان ، المسؤولية0
ISSN : ISSN: 1112- 5357 | E-ISSN : EISSN 2602 5736 | Vol : 19, N° : 01, pp : 227-256.
Auteur(s) : M. Belkhelfa, H. Boukhari, A. Hasni
Mots-clés : Thurston geometry · Hypersurface · Minimal · Totally umbilical · Pseudo-parallel · Sasakian
Vol : 59, N° : 4, pp : 739–760
Résumé : The aim of this paper is to give the conditions for the hypersurface γ × H2
to be minimal in Thurston geometry F4. In addition we show that γ ×H2 is not totally
umbilical neither pseudo-parallel nor Sasakian, where γ is a curve in R2 and H2 is
hyperbolic plane.
Auteur(s) : Abdel-Nour Zaim, , El Bahri Ould Chikh, Benattou Bouchouicha
Mots-clés : Thermoplastic elastomers, Rate-dependence, Stress-strain behavior, Volumetric strain
ISSN : 1229-9197 | E-ISSN : 1875-0052 | Vol : 19, N° : 4, pp : 734-741
Résumé :
In this article, the thermo-mechanical characterization of poly(butylene terephthalate)/poly(tetramethylene oxide)
(PBT/PTMO) is studied by thermal analysis, dynamic mechanical analysis, and uniaxial tensile tests. The results of
poly(ether esters) show that the melting temperature is equal to Tm=193 oC, which is 31 oC, lower than that of the melting
temperature of poly(butylene terephthalate) (PBT). Its glass transition temperature, Tg is equal to -61 oC, determined by
DMA. The melting and cooling temperatures (Tm, Tc) after aging at T0+48 h and T0+week are virtually unchanged. Moreover,
the results of the tensile tests show that the effect of the low deformation rate reduces the friction resulting from the sliding
mechanisms between the amorphous and crystalline parts.
Auteur(s) : Abdel-Nour Zaim, , El Bahri Ould Chikh, Benattou Bouchouicha
Mots-clés : Thermoplastic elastomers, Rate-dependence, Stress-strain behavior, Volumetric strain
ISSN : 1229-9197 | E-ISSN : 1875-0052 | Vol : 19, N° : 4, pp : 734-741
Résumé :
In this article, the thermo-mechanical characterization of poly(butylene terephthalate)/poly(tetramethylene oxide)
(PBT/PTMO) is studied by thermal analysis, dynamic mechanical analysis, and uniaxial tensile tests. The results of
poly(ether esters) show that the melting temperature is equal to Tm=193 oC, which is 31 oC, lower than that of the melting
temperature of poly(butylene terephthalate) (PBT). Its glass transition temperature, Tg is equal to -61 oC, determined by
DMA. The melting and cooling temperatures (Tm, Tc) after aging at T0+48 h and T0+week are virtually unchanged. Moreover,
the results of the tensile tests show that the effect of the lo
Auteur(s) : BENMESMOUDI AALI
Mots-clés : examinations, cheating
ISSN : 2311-5181 | N° : 39, pp : 139-147
Résumé : this article is about a phenomenon which threatens the integrity of the educational evaluation, mainly the national examinations, such as Baccalaureate and BEM
Auteur(s) : MF Bekkara, L Dascalescu, Y Benmimoun, T Zeghloul, A Tilmatine, N Zouzou
ISSN : 1286-0042 | E-ISSN : 1286-0050 | Vol : 81, N° : 1, pp : 1-7
Auteur(s) : Hachellaf Kaddour, Meddah Hadj Miloud, Ould Chikh El Bahri et Lounis Abdellah
Mots-clés : Polymères, essais de traction, FSW, FEM, couplage, procédé-propriété
N° : 18, pp : 83-86
Résumé : Le but de notre travail expérimental est de proposer un modèle d’outil qui pourrait être utilisé comme un outil prédictif pour obtenir
une bonne soudure des polymères comme le PEHD par la technique de soudage par friction malaxage FSW ou un soudage linéaire des
plaques plates minces. Une série des essais expérimentaux concernant ce type de soudage (FSW) ont été réalisés avec différents type
d'outils en fonction des paramètres optimaux de soudage tel que la vitesse d'avance, la vitesse de rotation, la forme géométrique d’outil, …
etc. Des résultats satisfaisants ont été obtenus montrant l’influence de ces paramètres sur la qualité du joint.
Auteur(s) : Samir Habibi, Noureddine Mahmoudi, Benaoumeur Aour, Laid aminallah, Ould Chikh el bahri
Mots-clés : Heat treatments; Characterization; Nanoindentation; Modulus of elasticity; Hardness
Vol : 2, N° : 002, pp : 168 – 174
Résumé : The thermal affectation is the basis of metallurgical modifications of the base metal
which can induce fragilities, decreases in mechanical strength, lack of ductility ... These
modifications depend on the material examined, the process used, the mode of operation
followed ... This research is devoted to the experimental study, whose objective is the
study of low-carbon steels who sustained of the various heat treatments. Then, the
instrumented nanoindentation test is developed to analyze the characteristic loading and
unloading curves of the examined specimens. In this case, we focus on the effect of heat
treatments on the metallographic examination and the mechanical properties of the
studied steels. At the same time, we study the coherence of the results obtained between
the heat treatment and the nanoindentation process in the determination of elasticity
modulus and hardness.
Auteur(s) : Abdel-Nour Zaim, Benattou Bouchouicha, Meddah Hadj Miloud, EL Bahri Ould Chikh
Mots-clés : Triaxiality, Plastic instability, polyester; Damage
ISSN : 1663-4144 | Vol : 34, pp : 13-28
Résumé :
In this work, we focus on a new generation of polymer named Polybutylene terephthalate
(PBT). In order to analyse and determine true behaviour of this polymer, a special experimental
method was used. Hence, the true stress/strain responses are investigated under a large plastic
deformation in different stress triaxiality frameworks with a particular attention on the volumetric
strain evolution, with their decomposition to an elastic volumetric strain, plastic volumetric strain
and the pure shear. Moreover, the effect of stress triaxiality on the plastic instability and the fracture
strain is also examined. With the plastic instability analysis, it was found that plastic strain
hardening increases gradually with the triaxiality. Finally, in order to evaluate the damage of this
polymer, a theoretical damage formula is proposed.
Auteur(s) : Bouzir Habib
Mots-clés : generalized Kählerian manifolds, generalized contact structures, generalized almost complex structures.
Résumé : Le concept de la géométrie généralisée est dû à Nigel Hitchin (\cite{hg}, 2003), et elle est intéressante dans la théorie physique de la supersymétrie. En géométrie généralisée on étudie non pas le fibré tangent d'une variété différentiable $M$, qui est noté $TM$ mais plutôt la somme du fibré tangent et du fibré cotangent, que nous noterons par $\mathds{T}M:=TM \oplus T^{*}M$, qu'on appel le fibré de Pontryagin (ou le fibré tangent généralisé) sur la variété $M$ avec la somme de Whitney $TM \oplus T^{*}M$ des fibrés tangent et cotangent.\\
Auteur(s) : Mohammed Seghir GUELLIL? Mostéfa BELMOKADDEM, Samir GHOUALI
ISSN : 2547-8818 | Vol : 4, N° : 10, pp : 406-416
Auteur(s) : Mohammed Seghir Guellil, Mostefa Belmokaddem, Samir Ghouali
Mots-clés : Agriculture gross production value, arable land, active population, energy consumption, panel co - integration, panel Granger causality.
ISSN : 2547 - 8818 | Vol : 04, N° : 10, pp : 406-416
Résumé :
The overall goal of this paper is to investigate the long run and casual relationship between agriculture gross production value (AGPV), arable land (AL), total economically active population in agricultural sector (APA) and total primary energy consumption in the agricultural sector given the historical trend of the se variables. For a panel of 76 countries during the period 1991–2012, the paper’s three main findings are that: (i)Neutrality hypothesis is adopted because there is no causality between AL and AGPV.; (ii) APA-led AGPV; (iii) Feedback hypothesis indicates that there are four cases of bidirectional causality between the rest of the variables. Adaptation measures are recommended for both authorities and farmers to ensure food security, such as providing incentives for farmers to adopt more recent technologies, which consumes less energy, land reclamation, steer more employees towards the agricultural sector.
Auteur(s) : ben azzouz saber
Mots-clés : securite
ISSN : 243-115 | N° : 05, pp : 104-113
Auteur(s) : Mustapha Mansouri
Mots-clés : Internet Addiction, Psychological disorders Students, secondary school
ISSN : 2304-3717 | E-ISSN : 2312-8003 | N° : 41, pp : 386-396
Résumé : The present study aim at identifying the level of Internet addiction and its Relation to some Psychological disorders among secondary school Students and to identify the differences in psychological disorders to the degree of addiction and differences Psychological disorders of Internet addicts according to gender variableThe sample consisted of 258 Studentswho taught in the secondary schools of Mascara in western Algeria; Applied the Internet addiction test and psychological disorders questionnairethe study revealed the following results:
-There is a positive correlation between Internet addiction and psychological disorders among secondary school students
- There are differences in psychological disorders among high and low Internet addicts of secondary school students in favor of addicts
-There are differences in the psychological disorders of Internet addicts according to the gender variable in favor of females
Auteur(s) : Benounissa Leila& BENABOU Djillali
Mots-clés : knowledge economy, investing in people, human development, education, patents.
E-ISSN : 2602-6651 | Vol : 1, N° : 2, pp : 54-63
Résumé : From the important slogan: humans are a capital that must be invested, in order to take advantage of their capabilities and output their capacity for survival, exploration, analysis restoration, innovation and creativity to focus on investing the remaining natural, material, human and social capitals. We will try in this paper to address the standard study in Algeria during the period 1990 -2007 and that by exploring the evolution of the human development index, education and indicators as well as the number of patents in Algeria throw the test of the variables stability used in the study, and the correlation between these variables. Finally causality test of Granger. The aim of this study is to address the importance of human resources and the need to invest in people to move towards a knowledge economy.
Auteur(s) : S. Doucha, M. Abri, H. Abri Badaoui, B. Fellah
ISSN : 2088-8708 | E-ISSN : 10.11591/ijece.v7i6.pp3467-3474 | Vol : 07, N° : 06, pp : 3467~3474
Résumé : A new type of leaky-wave antenna (LWA) using half-mode substrate integrated waveguide (HMSIW) as the base structure is proposed in this paper. The structure consists of an array of slot, antenna designed to operate in X band applications from 8 to 12 GHz. HMSIW preserves nearly all the advantages of SIW whereas its size is nearly reduced by half. The antenna radiates one main beam that can be steered from the backward to the forward direction by changing frequency. Copyright © 2017 Institute of Advanced Engineering and Science. All rights reserved.
Auteur(s) : A. Remil, Y. Mouchaal , A. B. Reguig, A. L. Toumi, h. Gherrass, A. Hachemaoui, A. Yahiaoui , A. Khelil
Résumé : The mastery of the optoelectronic properties of conjugated copolymers by substituting their radicals
is a promising way for increasing the light absorption and charge career transport in the organic
devices active layer. In this paper, we present the chemical synthesis of four di®erent conjugated
benzaldehyde derivatives and pyrrole-based copolymers (P–P:B) followed by their conception in
thin ¯lms on glass substrates by dip coating root from a solution in dichloromethane.
Auteur(s) : R.mounia, K.Nnouria, B.kouider
Mots-clés : التجارة الدولية، سوق العمل، خلق فرص العمل، المحتوى في مجال العملية الدولية، انفتاح المحلية للصناعات التحويلية
ISSN : 2519-9293 | E-ISSN : 2519-9285 | Vol : 3, N° : 1, pp : 174-190
Résumé : الهدف من هذا العمل هو الدراسة الكمية لتأثير التجارة الدولية على حركة خلق و تدمير الوظائف في الصناعة التحويلية للجزائر، من خلال تطبيق طريقة مضمون العمالة في التجارة الدولية، بالاضافة لاقتراح نموذج لقياس أثر تحرير التجارة على العمالة المحلية في الصناعات التحويلية على المدى الطويل و القصير، و لاظهار الى أي مدى تؤثر تدفقات التجارة الخارجية على هيكل العمالة المحلية في الصناعات التحويلية.
Auteur(s) : Amina Houari, Wassim Ayadi, Sadok Ben Yahia
Mots-clés : Biclustering; Negative correlations; Generic Association Rules ; Data mining; Bioinformatic; DNA microarray data.
ISSN : 1877-0509 | Vol : 112, pp : 278-287
Résumé : A majority of existing biclustering algorithms for microarrays data focus only on extracting biclusters with positive correlations of genes. Nevertheless, biological studies show that a group of biologically significant genes may exhibit negative correlations. In this paper, we propose a new biclustering algorithm, called NBic-ARM. Based on Generic Association Rules, our algorithm identifies negatively-correlated genes. To assess NBic-ARM’s performance, we carried out exhaustive experiments on three real-life datasets.
Our results prove NBic-ARM’s ability to identify statistically and biologically significant biclusters.
Auteur(s) : E. Abdelkader, H. Mohammed, B. Boumediene, B. Sid Ahmed
Mots-clés : Climate change Water resources Spatial variability Drought Macta watershed Algeria
ISSN : 1866-7511 | E-ISSN : ******* | Vol : 10, N° : 22, pp : 1-14
Résumé : This work describes the climate change impact study on rainfall patterns in Macta watershed, located in the northwest of Algeria. The monthly rainfall data collection, verification and validation have built a database with 42 stations, each with 42 years of observations from 1970 to 2011. The study of annual total rainfall has identified a downward trend and quantifies the deficits that are within the observation time series. The division of the annual rainfall series into four periods allowed to highlighting the increase in inter-year temporal variability with the coefficient of variation increases from 17 to 27%. The study shows an annual rainfall deficit increment from 13 to 25%. The standard deviation values decrease significantly for the last two periods showing a spatial variability. Multivariate statistical study by the hierarchical clustering method resulted in the formation of station groups indicating the unification of monthly rainfall patterns.
Auteur(s) : شعنبي نور الدين
Mots-clés : القلق،الخوف، الموت، قلق الموت
ISSN : 2437-0363 | N° : 9, pp : 176-186
Résumé : هدفت الدراسة إلى الكشف عن مستوى قلق الموت لدى عينة من اﻟﻤﺠتمع الجزائري، وكذا التعرف على الفروق في مستوى الشعور بقلق الموت تبعا لمتغير الجنس والمستوى التعليمي والحالة الاجتماعية والسن، جرت الدراسة بمدينة معسكر حيث تكونت عينة الدراسة من 106 فرد تم اختيا رهم بطريقة عشوائية، طبق عليهم مقياس قلق الموت، وتمت المعالجة الإحصائية للبيانات ببرنامج الرزم الإحصائية للعلوم الاجتماعية، وكشفت الدراسة عن النتائج التالية:
- وجود مستوى مرتفع من قلق الموت لدى عينة الدراسة.
- توجد فروق دالة إحصائيا في درجة قلق الموت تبعا لمتغير الجنس.
- لا توجد فروق دالة إحصائيا في درجة قلق الموت تبعا لمتغير الحالة الاجتماعية والمستوى التعليمي والسن .
Auteur(s) : Mazot A.
Mots-clés : polyphonie, discours de presse, locuteur, énonciateur, point de vue.
ISSN : 2507-721X | Vol : 2, N° : 1, pp : 79-86
Résumé : Notre étude s’inscrit dans le cadre de la théorie de polyphonie linguistique. Notre corpus est composé d’un ensemble d’énoncés tirés du Quotidien d’Oran. Nous nous attachons à analyser quelques marques de polyphonie permettant au journaliste d’introduire d’une façon explicite ou implicite une ou plusieurs voix dans son discours, tout en véhiculant des points de vue et en exprimant des attitudes envers son énoncé et les voix qu’il met en scène. Nous nous inspirons des travaux menés par Oswald Ducrot (1980/1984) et Jean Claude Anscombre (1983) qui relèvent essentiellement de la linguistique de l’énonciation, de la théorie de l’argumentation dans la langue et de la théorie de polyphonie linguistique.
Auteur(s) : Beldjilali gherici
Mots-clés : Golden Riemannian manifold, Almost Hermitian manifold, Almost contact metric manifold.
ISSN : 0138-4821 | Vol : 59, N° : 4, pp : 761-777
Résumé : We introduce the notion of Golden Riemannian manifolds of type (r, s) and starting from a Golden Riemannian structure, we construct some remarkable classes of the induced structures on Riemannian manifold. Concret examples are given.
Auteur(s) : Beldjilali gherici
Mots-clés : locally conformally Kähler manifold, Sasakian manifold, product manifolds.
ISSN : 0972-415X | Vol : 20, N° : 4, pp : 427-441
Résumé : The purpose of this paper is to determine some remarkable classes of the induced structures on the product of a locally conformally Kähler manifold with the real line and an almost contact metric manifold.
Auteur(s) : K. Zegga, G. Beldjilali and A. Mohammed Cherif
Mots-clés : product manifolds, Sasakian structures, Kählerian structures.
ISSN : 0972-415X | Vol : 20, N° : 4, pp : 409-425
Résumé : In this paper, we construct a Sasakian structure on the product of Sasakian manifold and Kählerian manifold with exact Kähler form.
Mots-clés : لامية، الأفعال، الوهراني، شرح ابن مالك
ISSN : 2437-0738 | Vol : 3, N° : 3, pp : 223-244
Résumé : حاولت في الورقة البحثية ان أميط اللثام عن احد أعلام الجزائرية في علم اللغة وفروعها، خاصة وأن صاحب هذا الشرح أعني الوهراني مغمور لا توجد له تراجمة في كتب التراجم، وكان الغرض في إجلاء جهود علماء الجزائر في الشروح الصرفية ، مبينا منهجه في الشرح بعد التعريف به وقيمة الشرح في ميزان الشروح الصرفية
Auteur(s) : S.Benyakhou
Mots-clés : alcohol dehydrogenation; biomass; lignin; bio-char; CO2 gasification; activated carbon; sodium
ISSN : 2073-4344 | Vol : 1150, pp : 580-585
Résumé : Hydrochloric acid functionalized silica gel (SiO2) has been successfully used for the grafting of poly(2-Aminophenyl disulfide) (poly(2APhS)) moieties through in-situ polymerization in the presence of ammonium peroxodisulfate (APS) as oxidant. The organic-inorganic hybrid (poly(2APhS)/SiO2 with different amounts of SiO2: 0.5 g, 1.5 g and 2 g) were thoroughly characterized through powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and ultraviolet spectroscopy (UV) measurements. The results confirm the successful formation of the poly(2APhS)/SiO2 composite. The surface morphology of the samples was characterized by transmission electron microscopy (TEM). The obtained images show the formation of poly(2APhS) on surface of silica gel. Although the incorporation of SiO2 nanoparticles reduces the electric conductivity of the poly(2APhS), the resulting samples still keep high conductivities, ranging between 8.2 × 10−4 to 1.1 × 10−6 S cm−1. The electrochemical properties of the composite were characterized by the cyclic voltammetry. The comparison between the different samples shows that the electrochemical activity is significantly depending on the amount of added SiO2. There is a clear and good electroactivity for poly(2APhS)/SiO2 with amounts of SiO2: 0.5 g and 1.5 g, respectively, compared to that observed in materials nanocomposite with amounts of SiO2: 2.0 g. However, that effect may be explained by a decrease of polymer in surface area with increase amount of SiO2 nanoparticle.
Auteur(s) : F. J. G. Mateos
Mots-clés : alcohol dehydrogenation; biomass; lignin; bio-char; CO2 gasification; activated carbon; sodium
ISSN : 2073-4344 | Vol : 7, pp : 308
Résumé : The properties of lignin and its potential as a renewable source make it an ideal precursor for carbon products. Specifically, the high content of Na observed in Kraft lignin makes this industrial by-product an interesting precursor for the preparation of catalysts for different applications. In this work, basic activated carbons with different textural properties and surface chemistry were obtained from Kraft lignin by direct carbonization at various temperatures. The influence of a further washing treatment and partial gasification with CO2 was also evaluated. The carbon catalysts were tested as catalysts for the alcohol decomposition reaction. In this sense, 2-propanol, a molecule widely used for testing the acidic-basic character of heterogeneous catalysts, was selectively transformed into acetone, meanwhile, ethanol and methanol yielded mainly acetaldehyde and formaldehyde, respectively.
Auteur(s) : Mohamed A. MEDEBBER, Noureddine RETIEL
Mots-clés : natural convection, Finite Volume Method, partially annular, Nusselt number
ISSN : 1428-1511 | E-ISSN : 2354-0192 | Vol : 22, N° : 1, pp : 71–86
Résumé : A study of free convection in a vertical cylinder partially annulus is conducted numerically.
Uniform temperature is imposed cross a vertical wall, while the top and bottom
walls are adiabatic. The governing equations are solved numerically by using a finite volume
method. The coupling between the continuity and momentum equations is effected
using the SIMPLER algorithm. Solutions have been obtained for Prandtl numbers equal
to 7.0, Rayleigh numbers of 103 to 106 and height ratios of 0 to 1. The influence of
physical and geometrical parameters on the streamlines, isotherms, average Nusselt has
been numerically investigated.
Auteur(s) : B. Mohamed B. Mohammed
Mots-clés : Fourth elliptic equation; Nodal solutions; critical Sobolev exponent
ISSN : 17476933, 17476941 | Vol : 63, N° : 10, pp : 1421-1437
Résumé : Using a variational method, we prove the existence of nodal solutions to prescribed scalar Q- curvature type equations on compact Riemannian manifolds with boundary. These equations are fourth-order elliptic equations with critical Sobolev growth.
Auteur(s) : Mazot A.
Mots-clés : polyphonie, discours de presse, locuteur, énonciateur, point de vue.
N° : 14, pp : 391-401
Auteur(s) : F. Chouli
Mots-clés : Hybrid materials Nanoparticle Zinc oxide 4-Chloroaniline Electrical conductivity
ISSN : 1548-0569 | Vol : 38 , pp : 254-260
Résumé : Nanocomposites were successfully synthesized by the oxidative polymerization of p‐anisidine and/or aniline monomers (at initial “p‐anisidine:aniline” mole ratios of “100 : 0,” 50 : 50,” and “0 : 100”) with titanium(IV) oxide nanoparticles, in the presence of hydrochloric acid as a dopant with ammonium persulfate as an oxidant. The morphological, structural, conductivity, and electrochemical properties of the synthesized nanocomposites were studied using Transmission Electron Microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, and UV–vis spectroscopies. The presence of polymer on TiO2 nanoparticles in samples nanocomposites was confirmed by the Transmission Electron Microscopy coupled with Energy Dispersive X‐ray Spectroscopy. The thermal stability of samples nanocomposites were evaluated using the Thermogravimetric Analysis. Electrical conductivity of nanocomposites obtained is in the range of 0.08 − 0.91 S cm−1. The electrochemical behavior of the polymers extracted from the nanocomposites has been analyzed by cyclic voltammetry. Good electrochemical response has been observed for polymer films; the observed redox processes indicate that the polymerization on TiO2 nanoparticles produces electroactive polymers. These composite microspheres can potentially be used in commercial applications as fillers for antistatic and anticorrosion coatings. POLYM. COMPOS., 38:E254–E260, 2017. © 2015 Society of Plastics Engineers
Mots-clés : المسننين-الرعاية المؤسساتية-الحق في النفقة-دعم البقاء في الوسط الاسري
ISSN : 2147-3153 | E-ISSN : 2148-2217 | N° : 09, pp : 1-28
Résumé : تقوم السياسة الإجتماعية في الجزائر على مبادئ قارة منطلقها تكفل الدولة بكل أفراد المجتمع مع إعتبار الأسرة الأساس الذي ينبني عليه هذا التكــــفل، هــــذا الأخير يتخذ أشكالا مختلفة، تتعد بتعدد الأفراد المكونين لها و الذين يشكلون خارج الأسرة ما يعرف بالفئات الخاصة كالأطفال ، النساء، و المسنين و بربط هذه الفئات بالأسرة و بالجرائم التي أصبحت تقع داخلها تتأكد ضرورة إعتماد آليات فعالة للحماية عندما تكون الفئة المستهدفة هي فئة الأصول لتتضاعف ضرورات الحماية أكثر عندما يتعلق الأمر بالأصول المسنين، ما يجعل آليات الحماية تتنوع بين الآليات الإجتماعية و الآليات الجزائية.
ÖZET
Cezayir’de, toplumsal siyaset, toplumun bütün fertlerinin sorumluluklarını üstlenen yerleşik prensipler üzerine kuruludur. Bu prensipler bu sorumlulukları üstlenirken aileyi de temel olarak kabul etmektedir. Aile kurumu kendisini oluşturan fertlerin ve toplumda aile dışında bulunan özel kesimlerin –ki bunlar çocuklar, kadınlar ve yaşlılar olarak değerlendirilir- çeşitliliğine göre farklılık gösterir. Bu grupların aileyle ilişkilendirilmesi ve aile içinde işlenen suçların da göz önünde bulundurulmasıyla hedeflenen kitle bu temel kitle olunca ve durum yaşlıları da ilgilendirince yaşlı fertlerin korunmasındaki etkili tedbirlerin bulunmasının zorunluluğu daha da artmakta ve bu koruyucu tedbirler toplumsal tedbirler ve cezaî tedbirler olarak çeşitlilik göstermektedir
Abstract
The social policy in Algeria is built on solid principles, which state ensure all members of the community with the consideration of family foundation upon which the latter provide various forms, include a wide range of components individuals which form outside the family what is known as special categories, such as children, women, the elderly and linking these categories to the family and the crimes that happens inside. Therefore it is confirmed the need to adopt effective mechanisms of protection when the target category is the asset class to multiply the needs of protection more when it comes to aging assets, making protection mechanisms, ranging from social and penal mechanisms.
Auteur(s) : I. F.Bouguenna, A.Azaiz, A. Tahour
Mots-clés : Dynamics Electric vehicle Fuzzy sliding PMSM Sliding mode control
ISSN : 2088-8694 | Vol : 8, N° : 3, pp : 1050-1061
Résumé : This paper present a speed hybrid fuzzy-sliding mode control (HFSMC) of a
permanent magnet synchronous motor (PMSM) to ensure the traction of an
electric vehicle; at the first we applied the sliding mode control (SMC) with
three surfaces on the PMSM by taking into account the dynamics of the
vehicle; And afterwards we applied the fuzzy-sliding mode in which the
surface of the speed is replaced by a Fuzzy-PI controller; Simulation under
Matlab/Simulink has been carried out to evaluate the efficiency
and robustness of the proposed control on a system drive. It should be noted
that the reference speed is the European urban driving schedule ECE-15
cycle.
Auteur(s) : MF BEKKARA Y BENMIMOUN A TILMATINE K MILOUDI S FLAZIS
Mots-clés : Reactor, Cold plasma Glow discharge Sputtering Vacuum
ISSN : 0304-3886 | Vol : 88, pp : 225-231
Auteur(s) : Nehal Laounia, Hamimed Abderrahmane, Khaldi Abdelkader, Souidi Zahira, Zaagane Mansour
Mots-clés : evapotranspiration, remote sensing, METRIC, energy balance, Landsat
ISSN : 0102-7786 | E-ISSN : 1982-4351 | Vol : 32, N° : 4, pp : 691-702
Résumé : Monitoring evapotranspiration and surface energy fluxes over a range of spatial and temporal scales is crucial for many
agroenvironmental applications. Different remote sensing based energy balance models have been developed, to estimate
evapotranspiration at both field and regional scales. In this contribution, METRIC (Mapping EvapoTranspiration
at high Resolution with Internalized Calibration), has been applied for the estimation of actual evapotranspiration in the
Ghriss plain in Mascara (western Algeria), a semiarid region with heterogeneous surface conditions. Four images acquired
during 2001 and 2002 by the Landsat-7 satellite were used. The METRIC model followed an energy balance approach,
where evapotranspiration is estimated as the residual term when net radiation, sensible and soil heat fluxes are
known. Different moisture indicators derived from the evapotranspiration were then calculated: reference evapotranspiration
fraction, Priestley-Taylor parameter and surface resistance to evaporation. The evaluation of evapotranspiration
and surface energy fluxes are accurate enough for the spatial variations of evapotranspiration rather satisfactory than sophisticated
models without having to introduce an important number of parameters in input with difficult accessibility in
routine. In conclusion, the results suggest that METRIC can be considered as an operational approach to predict actual
evapotranspiration from agricultural areas having limited amount of ground information.
Auteur(s) : BOUZIR Habib, BELDJILALI gherici, BELKHELFA mohamed, AISSA Wade
Mots-clés : product manifolds, trans-Sasakian manifolds, generalized Kählerian manifolds, generalized contact structures, transformation of generalized almost contact structures, generalized almost complex structures.
ISSN : 1212-5059 | E-ISSN : 0044-8753 | Vol : 53, N° : 1, pp : 35-48
Résumé : The aim of this paper is two-fold. First, new generalized Kähler
manifolds are constructed starting from both classical almost contact metric and almost Kählerian manifolds. Second, the transformation construction on classical Riemannian manifolds is extended to the generalized geometry setting
Auteur(s) : Diaf Fredj
Mots-clés : polyphonie argumentative, stratégies discursives, surgissements, coïncidences, la situation du discours, l’entourage affectif, variables argumentatifs, le présupposé, le posé, les enchaînements, source d’hypothèses, manœuvres.
ISSN : 6858-1112 | Vol : revue, N° : 7, pp : 59-80
Résumé : Notre recherche se focalise sur la conception énonciative du sens, cas des slogans engagés dans les législatives 2012, baptisées printemps algérien. C’est précisément une étude sur la polyphonie argumentative articulée par l’activation, d’une part, des variables argumentatives ‘‘mais’’ introduisant la restriction, la précision et la correction et ‘‘pour’’ dans la caractérisation de la notion de changement (conditions et signification). Quant à la négation, elle se considère comme un jugement sur un jugement dans la mesure où une proposition affirmative traduit ce sentiment. Et d’autre part, des fragments tirés des chansons sportives dans la confection des slogans des campagnes électorales. Certes la situation de discours et l’entourage affectif en sont autres mais là le paramètre de la coïncidence intervient pour donner une interprétation de discours. Notre étude a révélé le non-dit à travers le dit.
Auteur(s) : B.kamel.Y.souad.A.rachid
Mots-clés : oeuvres social .service social
ISSN : 2170-0907 | N° : 9, pp : 311-324
Résumé : les oeuvres sociales des travailleures sont etroitement liees a la politique sociale de letat ayant une humanitaire vu le premier concept duquel elles sont generees a savoire le service social.
cependant limiter l objet des oeuvres sociales dans le cadre des relations de travaile comme l une des branches de la protection sociale lui confere le caractere du droit conscacre par la loi que tout emploiyeure doit garantir dans les limites des possiblites qui lui sont offertes.
Auteur(s) : Samir Ghouali, Yassine Zakarya Ghouali, Mohammed Feham
Mots-clés : Panel Co-integration, Panel Granger Causality, FMOLS and DOLS Estimators, Cardiorespiratory electromyography galvanic signals
ISSN : 2156-5570 | Vol : 08, N° : 02, pp : 156-165
Résumé :
To examine the long-term causality between Cardiorespiratory Electromyography Galvanic signals for 17 drivers taken from Stress Recognition in Automobile Drivers database.
Methods: Two statistical methods, co-integration to reveal an eventual existence of a long-term relationship between ECG (Electrocardiograph),EMG (electromyography, GSR (galvanic skin resistance),heart rate (HR) and respiration,well as the Application of the model of Granger causality.
Results: ECG shows certain dependence to EMG,GSR, heart rate and respiration.The results for ECG dependent suggest that an increase of 1% in EMG, FOOTGSR, HAND GSR, HR and RESPIRATION implies a variation of ECG which take a value respectively of 0.016248%, 0.007241%, 0.028366%, 0.000511% and 0.000110% in the within dimension based on the FMOLS(Fully Modified Ordinary Least Squares).With same way, the result for ECG suggest that an increase of 1% in EMG, FOOT GSR, HAND GSR, HR and RESPIRATION implies a variation of ECG which take a value respectively,of 0.065684%, 0.014534%, 0.032800%, 0.000304%, 0.005986% in the between dimension based on the same method. The results of panel Granger causality show a bi-directional relationship between ECG and FOOT GSR, HAND GSR and respiration signals, it must be noted as a unidirectional causality from EMG to ECG.
Conclusion:This study shows the long-term interaction between the bio signals, and reveal how the understanding of these interactions can help the doctors to understand the risks
that may exist between these interactions. The main advantage of a multidimensional and multivariate model is to solve a multitude of problems that prevent doctors to treat the patients better and is not the case for studies in two dimensions.
Auteur(s) : O. Saiah, A. Hachemaoui, A. Yahiaoui
ISSN : ISSN 0930-777X | Vol : 04, pp : 515–518
Résumé : Herein, we describe the synthesis of polyfuran, polyaniline,
and their copolymer nanocomposites by in-situ oxidative polymerisation
of corresponding monomers in the presence of
montmorillonite, using ammonium persulfate as an oxidant.
The obtained nanocomposites were characterised by Fourier-
transform infrared spectroscopy, X-ray diffraction analysis,
and UV-vis spectroscopy.
Auteur(s) : B. Djilali, R. Bachir , H. Ahmed, B. Zaouaoui, S. Fatima, O.Y. Karima, B. Sid Ahmed
Mots-clés : lactic acid production, date juice, streptococcus thermophilus
ISSN : 2572-8466 | E-ISSN : ++++++ | Vol : 3, N° : 3, pp : 362?364
Résumé : The interest in the fermentative production of lactic acid has increased due to the prospects of environmental friendliness and of using renewable resources instead of petrochemicals. In this context, we have judged that is gainful to use the date juice which is with a low commercial value as a substrate for the production of lactic acid by Streptococcus thermophilus. Further, dates are rich in sugar ranging from 65% to 80% on dry weight basis mostly of inverted form (glucose and fructose), which can used as carbon source for the fermentation and the production of microbial biomass. The parameters optimization for lactic acid production by S. thermophilus grown on medium based on dates in order to improve yields is applied in this study. The results showed that the maximum of lactic acid production (36.9g/l) is obtained after the enrichment of date juice with yeast extract (15%), Tween 80 (1g/l) MgSO4 (0.5g/l), MnSO4 (0.02g/l) and K2HPO4 (1g/l).
Auteur(s) : Mohamed A. MEDEBBER, Noureddine RETIEL
Mots-clés : Double-diffusive convection, the finite volume method, partially annular, the Nusselt number, the Sherwood numbers
ISSN : 1662-9507 | Vol : 374, pp : 1-17
Résumé : This article reports a numerical study of double-diffusive convection within the annular
region of two concentric vertical cylinders. The outer vertical wall is maintained at lower uniform
temperature and concentration, while the inner vertical wall is maintained at higher uniform
temperature and concentration. The top and bottom horizontal walls are adiabatic and impermeable
to mass transfer. The resulting governing equations are solved using a finite volume method. The
coupling between the continuity and momentum equations is solved using the SIMPLER algorithm.
The compilations have been obtained for Prandtl numbers (Pr) equal to 7.0, and Lewis number (Le)
equal to 100. The thermal Rayleigh number (RaT) and height ratio (X) are, respectively, varied in
the range 103≤RaT≤106 and 0.0≤X≤1.0. The influence of physical and geometrical parameters on
the streamlines, isotherms, isoconcentrations, average Nusselt and Sherwood numbers has been
numerically investigated in detail
Auteur(s) : Nawel Kermas, Bouaza Djellouli, Driss Bouguenna*, Wondwosen Eshetu, Oana Moldovan and Benjamin Iñiguez
Mots-clés : I-V and C-V characteristics, Transconductance, AlxGa1−xN/GaN, HEMTs, Mole fraction, Threshold voltage, Numerical simulation, Atlas TCAD simulator
ISSN : 1569-8025 | E-ISSN : 1572-8137 | Vol : 17, N° : 1, pp : 224–229
Auteur(s) : Ahmed Larbaoui, Baghdad Belabbes, Abdelkader Meroufel, Driss Bouguenna
Mots-clés : Machine synchrone à aimant permanent (MSAP), Contrôle robuste, Régulateur hybride par mode glissant, Commande par logique floue (CLF), Commande par mode glissant (SMC), Régulateur mode glissant floue (RMGF) (Permanent magnet synchronous motor (PMSM), Robust control, Sliding mode hybrid regulator, Fuzzy logic control (FLC), Sliding mode control (SMC), F
E-ISSN : 0035-4066 | Vol : 62, N° : 2, pp : 192-196
Auteur(s) : A Nadjem, M Kachi, MF Bekkara, K Medles, T Zeghloul, L Dascalescu
ISSN : 0304-3886 | Vol : 86, pp : 18-23
Auteur(s) : B. Bouchouicha, M. Zemri, A. Zaim, B. Ould Chikh
Mots-clés : Microhardness · Plastic zone · Local energy · Cracking · E48 Steel
ISSN : 2369-0739 | E-ISSN : 2369-0747 | Vol : 192, pp : 107–116
Résumé : The fatigue damage of a material generally
goes through of an incident or a heterogeneity producing
a local stress concentration. The growth of crack is
related to the existence of a plastic zone at the crack
tip and accompanied by an energy dissipation. The
objective of this study is to analyze the evolution of
the energy at the crack tip during the propagation of
a crack in a welded joint. In order to determine the
energy nearest the end of the crack in the plastic zone,
we used microhardnessmeasurements. The estimate of
the total strain in each measurement point was determined
by a polynomial relation between Hv and εt /2.
After the determination of the average strain, the total
energy in each zone was deducted. The higher value
of this energy is in the Weld Metal, it is more lower
in the Base Metal and even lower in the Heat Affected
Zone.
Auteur(s) : Habib Bouzir, Gherici Beldjilali, Mohamed Belkhelfa, and Aissa Wade
Mots-clés : eneralized Kählerianmanifolds, generalized contact structures, generalized almost complex structures.
Vol : Tomus 53, N° : 53,
Résumé : The aim of this paper is two-fold. First, new generalized Kählermanifolds are constructed starting from both classical almost contact metricand almost Kählerian manifolds. Second, the transformation constructionon classical Riemannian manifolds is extended to the generalized geometrysetting
(2) (PDF) Generalized Kählerian manifolds and transformation of generalized contact structures. Available from: https://www.researchgate.net/publication/315969588_Generalized_Kahlerian_manifolds_and_transformation_of_generalized_contact_structures [accessed Oct 06 2020].
Auteur(s) : Z. M'hamed
Mots-clés : Taux de change, régime du change, croissance économique, Afrique du Nord.
E-ISSN : 2600-6197 | Vol : 8, N° : 1, pp : 47-59
Résumé : L’objectif de cette étude est d’analyser la relation empirique entre le régime de change et la croissance économique pour certains pays de l’Afrique du Nord (Algérie, Egypte, Maroc et Tunisie), entre 1980 et 2014. Les résultats obtenus suggèrent un effet significatif du régime de change sur la croissance, que ce soit par le biais d’une combinaison de l’accroissement des échanges commerciaux et du taux d’investissement ou par celui d’un niveau important de l’ouverture commerciale. Il apparaît donc que l’abandon des régimes fixes observé par ces pays au cours de ces dernières décennies se justifie par un objectif de stabilité de leurs croissances.
Auteur(s) : A. Bekhoukh
Mots-clés : Hybrid materials Nanoparticle Zinc oxide 4-Chloroaniline Electrical conductivity
ISSN : 0022-2860 | Vol : 27, pp : 13-20
Résumé : 4-Chloroaniline (4ClAni) in the presence of zinc oxide (ZnO) nanoparticles were prepared by chemical oxidative polymerization in hydrochloric acid solution using Ammonium persulfate as oxidant. The effects of amount of ZnO nanoparticles (1, 1.5, 2, 2.5 and 3 g, respectively) on the properties of products were investigated. The obtained nanocomposites was characterized using XRD, IR, UV–visible, and XPS which confirmed the incorporation of the nanoparticle ZnO in the P(4ClAni) matrix and the maximum interaction occurs for 2 g ZnO loading. The TGA analysis was used to confirm the thermal stability and number of water molecules in each nanocomposites chain unit. Although the incorporation of ZnO nanoparticles reduces the electric conductivity of the P(4ClAni), the resulting nanocomposites still keep high conductivities, ranging between 2.19 × 10−2 and 5.92 × 10−4 S cm−1. Good electrochemical response has been observed for samples of amounts ZnO less than 2 g; the observed redox processes indicate that the polymerization on ZnO nanoparticles produces electroactive polymers. The P(4ClAni) layer adhered well to the ZnO nanoparticles and can be used as practical applications.
Auteur(s) : بن دحمان أمينة، ركراك مونية، عمراني فاطمة
Mots-clés : صدمات أسعار النفط، الانفاق الحكومي، اختبار سببية قرانجر
ISSN : 2170-0311 | E-ISSN : 2600-6197 | N° : 9, pp : 173-182
Résumé : الدافع من وراء هذه الدراسة هو البحث في طبيعة تأثير تقلبات أسعار النفط على السياسة المالية في البلاد, باستخدام منهجية سببية قرانجر وخلال الفترة الزمنية 1970-2014، من خلال تحديد اتجاه السببية بين تقلبات أسعار النفط الخام ( سعر النفط الحقيقي، الصدمات الموجبة لأسعار النفط، الصدمات السالبة لأسعار النفط) و أهم المتغيرات الرئيسية للسياسة المالية في الجزائر ( الانفاق الحكومي، نفقات التسيير و نفقات التجهيز). و من خلال نتائج الدراسة القياسية تم ايجاد علاقة سببية تتجه من أسعار النفط نحو مؤشرات الميزانية العامة في البلد، كل هذا يشير بقوة الى ضرورة تنويع الاقتصاد للحد من تأثير تقلبات أسعار النفط على عائدات الحكومة، ولا بد من الحكومة اشراك مبدأ التخطيط في الانفاق العام في البلاد.
Auteur(s) : B. Sid Ahmed, B. Kheloufi , B. Djilali, B.R. Ghalem, E. Abdelkader
Mots-clés : Pistachio, variety, lifted, seedlings, growth.
ISSN : 2090-4274 | E-ISSN : ++++++ | Vol : 7, N° : 3, pp : 157-165
Résumé : The present work is to study the emergence and growth of seedlings of five pistachio varieties that are: Batouri,
Achouri, Neb-Djemel, Adjmi and Bayadhi. The study was conducted in a greenhouse temperature and photoperiod
were controlled. The seeds are germinated in pots filled with peat without going through the damp cold
stratification at a temperature of 4ºC. The results obtained showed that growth parameters (length and diameter of
the plants) revealed significant tests while other parameters (emergence rate, root length and number of leaves per
plant) had showed no significant tests. About the number of emerged plants per day, variety Achouri comes first
while the variety Neb-Djemel comes last. About the number of emerged plants per day, variety Achouri comes first
while the variety Neb-Djemel comes last. For the evolution of growth in height, it is on average 2cm per week until
two months after emergence; then it becomes 0.37 and 0.88cm for the final week of growth.
Auteur(s) : Brahami Imen Souhila, Brahami Mostefa, Tilmatine Amar, Senoussaoui Mohammed El Amine
Mots-clés : Photovoltaic generator, Solar panels; tracker; yield, optimization
ISSN : 1582-4594 | Vol : 17, N° : 3, pp : 178-187
Résumé : Electricity generation using conventional sources such as fossil fuels raises a lot of problems either economically since it is a non-renewable or environmentally, due to the release of greenhouse gas that are the main causes of global warming. Electrical energy from photovoltaic effect provides an alternative to that produced in fossil energy power plants since it is
sustainable and environmentally friendly. Many kinds of research have been conducted and still developing in order to improve overall solar system’s efficiency and especially photovoltaic ones. The solar tracker is one of the elements that contribute to increase the maximum power captured from solar panels by adjusting their position in an optimal direction towards the sun. In this paper, the design of low cost, solar generator provided with a new single axis
tracker (east-west) for a predetermined inclination of 30 degrees was developed. This new tracker, on sunny days, can increase the generation of the power station by 30% in comparison with a fixed system, even if it is made of cheap material, such as resistors and transistors. The generator follows the sun using a low power motor connected to a force multiplier; which provides a low energy consumption.
Auteur(s) : Fellah benzerga, Mehadji Abri, Hadjira ABRI Badaoui, JUNWU Tao
ISSN : 1109-2742 | E-ISSN : 2224-2864 | Vol : 16, N° : 39, pp : 347-352
Résumé : The aim of this paper is to present a novel technique for the design of millimetre substrate integrated waveguide (SIW) power dividers based on the Quick Finite Element Method. The return losses, transmission coefficients and the field's distribution are presented and analyzed by this technique. To present the validity and the performances of our structures, the obtained results are compared with CST commercial software in the band frequencies from 40 to 75 GHz. The numerical simulation program can provides useful design information as well as physical insights for frequencies in the millimeter wave range.
Auteur(s) : Mazot A.
Mots-clés : polyphonie, discours de presse, locuteur, énonciateur, point de vue.
ISSN : 1112-4245 | Vol : 2, N° : 9, pp : 95-113
Résumé : Notre étude s’inscrit dans le cadre de la théorie de polyphonie linguistique. Notre corpus est composé d’un ensemble d’articles tirés du Quotidien d’Oran. Nous nous attachons à analyser quelques marques de polyphonie permettant au journaliste d’introduire d’une façon explicite ou implicite une ou plusieurs voix dans son discours, tout en véhiculant des points de vue et en exprimant des attitudes envers son énoncé et les voix qu’il met en scène. Nous nous inspirons des travaux menés par Oswald Ducrot et Jean Claude Anscombre qui relèvent essentiellement de la linguistique de l’énonciation, de la théorie de l’argumentation dans la langue et de la théorie de polyphonie linguistique.
Auteur(s) : S. Benykhlef
Mots-clés : Polyaniline 2-Chloroaniline Aluminum oxide Nanocomposite Electrochemical properties
ISSN : 0303-402X | Vol : 294, pp : 1877-1885
Résumé : This paper presents the physicochemical, conductive, and electrochemical properties of different polyaniline (PANI)-derived polymer/Al2O3 nanocomposites synthesized by chemical oxidation polymerization method carried out in two stages: first, activation of the surface of the Al2O3 nanoparticles by hydrochloric acid and second, polymerization of 2-chloroaniline (2ClANI), aniline (ANI), and the copolymer (2ClANI-ANI) in the presence of Al2O3 by using ammonium persulfate as oxidant in aqueous hydrochloric acid. XRD and TEM results reveal the growth of the polymers on Al2O3 nanoparticles and the formation of PANI-derived polymer/Al2O3 nanocomposites. FTIR and UV-Vis show a systematic shifting of the characteristic bands of the polymers with the presence of Al2O3 nanoparticles. Moreover, these nanoparticles enhance the thermal stability of the polymers, as found by thermogravimetric analysis (TGA). Although the incorporation of Al2O3 nanoparticles reduces the electric conductivity of the polymers, the resulting nanocomposites still keep high conductivities, ranging between 0.3 × 10−2 and 9.2 × 10−2 S cm−1. As a result, the polymer/Al2O3 nanocomposites exhibit a good voltammetric response. All these synergetic features of the nanocomposites are assigned to the effective interaction of the polymers and Al2O3 particles at nanoscale.
Auteur(s) : خذير أسامة، بلمقدم مصطفى، قليل محمد صغير
ISSN : 1112-9786 | Vol : 5, pp : 206-228
Auteur(s) : صدار لحسن ،جعيجع عمر
Mots-clés : اختبار القدرة على التفكير الابتكاري ،الخصائص السيكومترية خصائص السيكوميترية
ISSN : 7872 1112 | E-ISSN : 2007 -1910 | Vol : 1, N° : 11, pp : 33-57
Résumé : هدفت الدراسة الحالية إلى تقنين اختبار القدرة على التفكير الابتكاري لسيد خير الله على تلاميذ السنة الأولى من التعليم الثانوي، تم تطبيق الاختبار على (100) تلميذ وتلميذة، منهم (55) أنثى، ومن خلال المنهج الوصفي تم التوصل إلى أن الاختبار يتمتع بصدق التمييز وصدق الاتساق الداخلي والصدق الذاتي، كما يتمتع أيضا بالثبات من خلال تجزئته أو إعادة تطبيقه بعد (15) يوما أو معامل ألفا كرونباخ، والخلاصة أن جميع الطرق المتبعة أكدت على تمتع الاختبار بخصائص سيكومترية عالية، وعليه يمكن الوثوق بنتائجه إذا ما طبق على عينة مماثلة لعينة الدراسة الحالية.
Auteur(s) : Yasser Bouzid, Houria Siguerdidjane, Yasmina Bestaoui, M Zareb
Mots-clés : Reference model IDA-PBC Autonomous UAV Internal energy Tracking control
ISSN : 0921-0296 | Vol : 87, N° : 2, pp : 341-362
Résumé : Motion control design plays a crucial role in autonomous vehicles. Mainly, these systems operate in conditions of under-actuation, which make the control a serious task especially in presence of practical constraints. The main objective within this paper is to ensure the tracking of 3D reference trajectory overcoming some of the issues related to the control of multi-rotor vehicles (such as underactuation, robustness, limited power, accuracy, overshoot, etc.). Therefore, a control scheme for Vertical Take Off and Landing (VTOL) multi-rotor Unmanned Aerial Vehicle (UAV) is designed, applying the Interconnection and Damping Assignment-Passivity Based Control (IDA-PBC) technique. As reference model based technique, the control specifications are readily met by fixing a desired dynamic model, which is a major advantage of the technique. Moreover, a port −controlled Hamiltonian representation is exploited in order to point out the physical properties of the system such as its internal energy. This latter is exploited, as a fitness function for an optimization algorithm, in order to decrease the consumed energy especially at the take-off step and allows the tuning of the controller parameters. The numerical simulations have shown satisfactory results that support the claims using a nominal system model or disturbed model. The designed controller has been implemented on a real vehicle for which one demonstrates, in an indoor area manipulation, the effectiveness of the proposed control strategy.
Auteur(s) : F. Z. Dahou
Mots-clés : Hybrid materials Nanoparticle Zinc oxide 4-Chloroaniline Electrical conductivity
ISSN : 1548-0569 | Vol : 35, pp : 411-418
Résumé : Polymer/clay nanocomposite particles with 2‐aminophenol (2AP) and polyaniline and modified montmorillonite by copper minerals were synthesized using an in situ intercalative oxidative polymerization method. The nanocomposites were characterized by elementary analysis, X‐ray diffraction, FTIR, thermogravimetric analysis, transmission electron microscopy, and conductivity measurements. The insertion of the polymer into the layer of the clay was confirmed by X‐ray diffraction analysis, which shows a significantly larger d spacing expansion from 13.35 to 13.45 Å, thus indicating that the conducting polymer chain was aligned with layers of the clay. The conductivity of the nanocomposites salt is between 8.87×10−5 and 9.78×10−4 S/cm, probably due to the confined environment in the nanometer size layers of the nanocomposite. The electrochemical behavior of the polymers extracted from the nanocomposites has been studied by cyclic voltammetry. Good electrochemical response has been observed for polymers grown into M‐Cu; the redox processes indicate that the polymerization into M‐Cu is electroactive.
Auteur(s) : M.A. Nouairi, T. Fergoug, M. Azayez, H. Boujoures, C. Zelmat, Y.Bouhadda
Mots-clés : Complexation, Tetracaine hydrochloride, 1H-NMR, β-Cyclodextrin, UV-Visible Spectrophotometry, quantum calculations
ISSN : ISSN: 2028-2508 | Vol : Volume 8, N° : issue 5, pp : 1589-1598
Résumé : The complexation of the drug Tetracaine-hydrochloride (TC,HCl) with β-
cyclodextrin (β-CD) was studied by means of UV-Visible Spectrophotometry and
positive electrospray ionization mass spectrometry ESI+/MS and 1D 1H-NMR. The
experimental results confirm that an inclusion complex was formed between the drug
and β-CD and that the cationic end of the guest molecule is inserted into β-CD cavity.
Quantum semi-empirical calculations were performed to determine the best inclusion
pathway between the cationic Tetracaine and the β-CD. Potential energy scan
showed that the most stable inclusion complex is obtained when the guest molecule
is inserted with its ammonium group into the cavity of β-CD from its wider rim in
accordance to experimental results.
Auteur(s) : F Kherbouche, Y Benmimoun, A Tilmatine, A Zouaghi, N Zouzou
Mots-clés : Electrostatic precipitator Corona discharge High resistivity particles Asymmetrical geometry Collection efficiency
ISSN : 0304-3886 | Vol : 83, pp : 7-15
Résumé : In this paper, a new electrostatic precipitator (ESP) with asymmetrical wire-to-cylinder configuration is investigated experimentally and numerically. The main objective is to evaluate the collection efficiency of high resistivity particles.The electrical measurements show that the corona discharge behavior is similar to that obtained in symmetrical wire-to-cylinder configuration. Results show that the collection efficiency can reach 95% in the case of negative corona discharge.
In order to understand the particle trajectories inside the ESP, the experimental results are compared with numerical simulation by using a coupled model. Numerical results indicate that particles can be collected on the collecting electrode backside.
Auteur(s) : BELDJILALI gherici, BELKHELFA mohamed.
Mots-clés : Kählerian structures, product manifolds, Sasakian structures
ISSN : 1312-5192 | Vol : 42, N° : 1, pp : 1-13
Résumé : We introduce the notion of D-homothetic bi-warping and starting from a Sasakian manifold M, we construct a family of Kählerian structures on the product R × M. After, we investigate conditions on the product of a cosymplectic or Kenmotsu manifold and the real line to be a family of conformal Kähler manifolds.
We construct several examples.
Auteur(s) : Fellah benzerga, Mehadji Abri, Hadjira ABRI Badaoui
Mots-clés : Substrate integrated waveguide (SIW) V-band Bend analysis Two dimensional finite element method (2D-FEM) CST Microwave Studio
ISSN : 12 | E-ISSN : 231 | Vol : 41, N° : 9, pp : pp 3335–3343
Résumé : In this paper, two classes of V-band substrate integrated waveguide (SIW) bends operating in V-band frequency in the range [58–63 GHz] for the 90∘90∘ SIW bend with inductive via and in the range [57–68 GHz] for the circular SIW bend and corporate 1×41×4 and 1×81×8 SIW power dividers that provide equal power split with high isolation in all output ports operating in V-band [45–80 GHz] are presented and studied. The advantages of the SIW technique are its low profile, low cost, mass production, ease of fabrication and full integration with planar circuits. All the SIW bend topologies are optimized and designed to operate in the V-band frequency range. The bends and dividers are analyzed using the two-dimensional finite element method (2D-FEM). The analysis was performed in H-plane using a powerful full-wave method based on the two-dimensional finite element method (2D-FEM) programmed under MATLAB environment. The return losses, transmission coefficients and the field’s distribution are exposed in this paper. To validate our results numerically, a comparison is made and the obtained results are compared with those given by the CST Microwave Studio. It is observed that the simulation computation time is reduced with good accuracy since the discretization was done only in two dimensions.
Auteur(s) : T. Seddik, GÖKAY Uğur, F Soyalp, R Khenata, Deo Prakash, IV Kityk, Saleem Ayez Khan, A Bouhemadou, S Bin-Omran, DP Rai, KD Verma
Mots-clés : Antiperovskite; FP-APW+LO; Magnetic properties; Elastic properties; Electronic band-structure; Thermoelectric properties
ISSN : 0749-6036 | Vol : 109, pp : 1-12
Résumé : In this work, we have theoretically investigated the band structure of antiperovskite chromium-based carbides and nitrides Cr3PX (X = C and N) using the first-principles calculation based on the FP-APW+LO method. The principal structural properties i.e., lattice constants (a,b,c) and internal parameters are in accordance with the experimental results. The calculated values of elastic constants indicated that the mechanical strength for both Cr3PC and Cr3PN compounds at (001) plane is higher than the (100) and (010) planes. Moreover, the Cr3PX compounds are expected to be hard materials with ductile nature. In addition, we have found that the FM ground state of herein materials Cr3PC and Cr3PN are energetically favorable with low magnetic moments of about 2.27 and 2.94 μB, respectively, confirming that these are weak ferromagnets. Based on the spin-polarized electronic band structure we have found that both alloys have metallic behavior, such behavior has been shown in the calculated electrical conductivity. We have also estimated other thermoelectric constants like the Seebeck coefficient, thermal conductivity, power factor and electrical resistivity of Cr3PC and Cr3PN compounds.
Auteur(s) : T. Seddik, GÖKAY Uğur, R Khenata, Ş Uğur, Fethi Soyalp, G Murtaza, DP Rai, A Bouhemadou, S Bin Omran
Mots-clés : Electronic structure, band gap, optoelectronic, FP-LAPW + lo, TB-LMTO
ISSN : 1674-1056 | Vol : 25, N° : 10, pp : 107801
Résumé : In the present work, we investigate the structural, optoelectronic and thermoelectric properties of the YLi3X2 (X = Sb, Bi) compounds using the full potential augmented plane wave plus local orbital (FP-APW+lo) method. The exchange–correlation potential is treated with the generalized gradient approximation/local density approximation (GGA/LDA) and with the modified Becke–Johnson potential (TB-mBJ) in order to improve the electronic band structure calculations. In addition, the estimated ground state properties such as the lattice constants, external parameters, and bulk moduli agree well with the available experimental data. Our band structure calculations with GGA and LDA predict that both compounds have semimetallic behaviors. However, the band structure calculations with the GGA/TB-mBJ approximation indicate that the ground state of the YLi3Sb2 compound is semiconducting and has an estimated indirect band gap (Γ–L) of about 0.036 eV while the ground state of YLi3Bi2 compound is semimetallic. Conversely the LDA/TB-mBJ calculations indicate that both compounds exhibit semiconducting characters and have an indirect band gap (Γ–L) of about 0.15 eV and 0.081 eV for YLi3Sb and YLi3Bi2 respectively. Additionally, the optical properties reveal strong responses of the herein materials in the energy range between the IR and extreme UV regions. Thermoelectric properties such as thermal conductivity, electrical conductivity, Seebeck coefficient, and thermo power factors are also calculated.
Auteur(s) : D. Bouguenna*, T. Wecker, D.J. As, N. Kermas and A. Beloufa
Mots-clés : Transmission coefficient • Density of states • Local density of states • Cubic AlxGa1−xN/GaN • Superlattice • Nanostructures • MODFETs • nextnano3
ISSN : 1569-8025 | E-ISSN : 1572-8137 | Vol : 15, N° : 4, pp : 1269–1274
Résumé : Numerical analysis of the transmission coefficient, local density of states, and density of states in superlattice nanostructures of cubic AlxGa1−xN/GaN resonant tunneling modulation-doped field-effect transistors (MODFETs) using nextnano3 software and the contact block reduction method is presented. This method is a variant of non-equilibrium Green’s function formalism, which has been integrated into the nextnano3 software package. Using this formalism in order to model any quantum devices and estimate their charge profiles by computing transmission coefficient, local density of states (LDOS) and density of states (DOS). This formalism can also be used to describe the quantum transport limit in ballistic devices very efficiently. In particular, we investigated the influences of the aluminum mole fraction and the thickness and width of the cubic AlxGa1−xN on the transmission coefficient. The results of this work show that, for narrow width of 5 nm and low Al mole fraction of x=20% of barrier layers, cubic AlxGa1−xN/GaN superlattice nanostructures with very high density of states of 407 eV−1 at the resonance energy are preferred to achieve the maximum transmission coefficient. We also calculated the local density of states of superlattice nanostructures of cubic AlxGa1−xN/GaN to resolve the apparent contradiction between the structure and manufacturability of new-generation resonant tunneling MODFET devices for terahertz and high-power applications.
Auteur(s) : BELDJILALI gherici, BELKHELFA mohamed.
Mots-clés : Almost Hermitian almost contact structure, almost contact metric manifolds with 3-structures, hyperkählerian structure.
ISSN : 1307-5624 | Vol : 9, N° : 2, pp : 80-86
Résumé : The purpose of this paper is to define some classes of almost contact metric 3-structures manifolds
and almost quaternionic metric with an almost Hermitian almost contact metric structure. Next,
we construct an almost quaternionic Hermitian structure on the product of two almost Hermitian
almost contact metric structures. This gives a new positive answer to a question raised by T.
Tshikuna-Matamba.
Auteur(s) : HOCINE ABDELHAK AZZEDDINE, MUSTAPHA TIOURSI, DJAMEL-EDDINE CHAOUCH, BRAHIM KHIARI
Mots-clés : PV, MPPT, RBF
ISSN : ?0035-4066 | Vol : 61, pp : 255-257
Résumé : In this work, we develop a radial basis artificial neural network to predict the voltage and the current at maximum power point of a photovoltaic panel under different cell temperature and solar irradiance conditions. For training the proposed artificial neural network, we generate a group of maximum power points defined by their corresponding current and voltage values using
the photovoltaic panel single diode model. To ensure the validity of the artificial neural network, we compare the obtained results to those obtained by using the photovoltaic panel single diode model for cell temperature and solar irradiance conditions other than those used for the training phase. Results show that the developed artificial neural network can predict accurately and quickly the current and the voltage of the photovoltaic panel at the maximum power point for any cell temperature and solar irradiance conditions.
Auteur(s) : Samir Ghouali, Mohammed Feham, Yassine Zakarya Ghouali
Mots-clés : Direction of information, Cardiorespiratory hemodynamic signals, Granger causality, Multivariate study, (MGH/MF) waveform database
ISSN : 2194-1009 | pp : 275-300
Résumé : Granger causality (GC) is one of the most popular measures to reveal causality influence of time series based on the estimated linear regression model and has been widely applied in economics and neuroscience due to its reliability, clarity, and robustness.
Granger causality has recently received increasing attention to study causal interactions of neurophysiological data; in this chapter we have developed a model of causality between the respiratory, hemodynamic, and cardiac signals, more specifically, a study based on the Granger causality between three ECG leads, blood pressure, central venous pressure, pulmonary arterial pressure, respiratory impedance, and airway CO2. We selected 187 patients of 250 for our study, taken from Montreal General Hospital/MF (Massachusetts General Hospital/Marquette Foundation) databases. These signals are ideal for understanding causality and coupling (unidirectional or bidirectional).
In this approach we aim to analyze and understand the interactions between the signals mentioned above, and identify the significance of this interaction. The originality of this chapter is the number of variables selected for the study. Unlike the majority of studies that are conducted only with two variables, our study is multidimensional. The main advantage of a multidimensional and multivariable model is to solve a myriad of problems which is not the case in the two-dimensional
studies.
Auteur(s) : Dr LEKKAM Abdelkrim Boudjelal
Mots-clés : Prix du pétrole, réserves de change, offre de monnaie, PIB, crédit intérieur, emprunt extérieur net, balance commerciale, balance des paiements, ajustement, AMBP, modèle POLAK.
ISSN : 1112-6191 | Vol : 12, N° : 12, pp : 16-29
Résumé : L’économie algérienne est fortement caractérisée par une dépendance d’exportation des hydrocarbures, des emprunts extérieurs, d’un contrôle des changes rigoureux de la part des pouvoirs publics et d’un marché informel dominant. En Effet, le « contre chocs » pétrolier de 1986 avec le resserrement de la contrainte extérieure de biens de consommation, celle-ci revêtant à ce jour, une double forme, importante facture alimentaire engendrant une aggravation du déficit commercial et l’obligation d’importer davantage de denrées alimentaire. Elle a obligé le gouvernement algérien à accroitre ses exportations et son ouverture commerciale afin de pouvoir dégager un excédent dans la balance des paiements (BP). L’approche monétaire à la balance des paiements constitue un cadre théorique permettant d’identifier les éléments des déséquilibres de la balance des paiements et du budget gouvernemental. À l’aide du modèle de POLAK, l’évaluation de certains paramètres et la compréhension des interactions existantes entre les différentes variables de l’économie, nous aiderons à mieux percevoir la nature de ces déséquilibres. Le but principal du modèle a toujours été l'analyse et la compréhension des déficits de la balance des paiements et les actions politiques mises en œuvre pour les surmonter. Il importe de clarifier la manière dont l’approche monétaire de la balance des paiements (AMBP) pourrait contribuer à identifier les éléments des déséquilibres de la balance des paiements extérieurs. Ainsi que les actions politiques mises en œuvre pour les surmonter. Nous avons estimé les paramètres du modèle pour la période de 2000 à 2013. D’où, nous avons signalé que les entrées nettes de capitaux non
Auteur(s) : Mohammed Seghir GUELLIL , Mostéfa BELMOKADDEM
ISSN : 1112-9786 | Vol : 4, pp : 1-15
Auteur(s) : Ibari Benaoumeur, Benchikh Laredj, Hanifi Elhachimi Amar Reda, Ahmed-foitih Zoubir
Mots-clés : Non-linear systems; Trajectory tracking; Dynamic model; backstepping
Vol : 2, N° : 3, pp : 478-485
Résumé : This paper proposes a backstepping controller design for trajectory tracking of unicycle-type mobile robots. The main object of the control algorithms developed is to design a robust output tracking controller. The design of the controller is based on the lyapunov theorem, kinematic tracking controller of an unicycle-like mobile robot is used to provides the desired values of the linear and angular velocities for the given trajectory. A Lyapunov-based stability analysis is presented to guarantee the robot stability of the tracking errors. Simulation and experimental results show the effectiveness of the proposed robust controller in term of accuracy and stability under different load conditions.
Auteur(s) : Abdenour Hamdaoui, Nadia Mezouar, Djamel Benmansour, and Driss Bouguenna*
Mots-clés : ames-Stein estimator, multivariate normal distribution, non-central chi-square distribution, quadratic risk, shrinkage estimator.
E-ISSN : 2278-5728 | Vol : 12, N° : 3, pp : 14-28
Auteur(s) : M. Khaldi, A. Vivet, A. Bourmaud, Z. Sereir, B. Kada
Mots-clés : composites; fibers; mechanical properties; resins; surfaces and interfaces
ISSN : 0021-8995 | E-ISSN : 1097-4628 | Vol : 133, N° : 31,
Résumé : In this article, we first review state‐of‐the‐art experimental techniques and measurements to characterize the mechanical properties of anisotropic vegetal alfa fibers, epoxy‐resin, and the behavior of the interphase between the matrix and alfa fibers. Second, we conduct experimental tests to determine the mechanical properties of fibers, resin, and the interphase. Third, we carry out a series of finite element simulations to predict damage initiation and to estimate crack propagation in alfa‐fiber/epoxy‐resin (AFER) composites. Different tests to determine the longitudinal Young's modulus of alfa fibers and epoxy resin as well as nanoindentation tests to obtain the transverse stiffness of the fibers are presented. Experimental results from the characterization are introduced in a micromechanical model to estimate, using the concept of the energy release rate (ERR), the matrix crack, and its interaction with interfacial debonding. The wettability problems in the preparation of vegetable composites and their effect on fiber‐matrix interfacial debonding are also addressed. The analysis of the damage behavior of AFER composites demonstrates that under load transverse to the fiber axis, a crack initiated in the matrix is propagated perpendicular to the direction of the load. Near the interface, the ERR decreases and this energy is higher in the presence of interfacial debonding areas generated by problems of fiber wettability.
Auteur(s) : B.kamel.Y.souad.A.rachid
Mots-clés : maladie professionnnelle
ISSN : 2477-9784 | N° : 01, pp : 286-301
Résumé : Pour determiner la notion maladie professionnelle il et necessaire d enfaire la distinction avec la notion de maladie ordinaire dont on fait a certains egards l amalgame avec la notion maladie professionnelle la notion d accident de travail souvent adjacente a celle de maladie professionnelle.
Auteur(s) : Jihong Xia, Genting Yu, Junqiang Lin, Weijie Cao, Zihan Yi, Lihuai Lin, Laounia Nehal
Mots-clés : riparian zone; slightly-curved; water pressure distribution; small-disturbance theory
Vol : 8, N° : 2, pp : 61
Résumé : A curved riparian zone can create highly complex flow patterns that have a great effect
on erosion, pollutant transport, surface water-groundwater exchange and habitat qualities. The
small-disturbance theory has been applied to derive the analytical solutions of pressure distributions
along a sinusoidal riverbank. Experiments have also been performed to test the hydrodynamic and
geomorphic effects on pressure distribution and to verify the applicability of the derived expressions.
The derived expressions were simple, accurate and agreed remarkably well with experimental
results for the riparian banks with a low degree of curvature. On the contrary, when a riparian
bank had a high degree of curvature, these expressions applying the approach of small-disturbance,
could not effectively estimate the pressure distributions for a complex bank boundary or complex
flow conditions. Moreover, sensitive analysis has indicated that the disturbed pressures along the
riparian banks increased with increasing Froude number Fr, as well as the ratio of bank amplitude
to wavelength a/. However, a/ has been found to have more significant influence on pressure
variation in subcritical flow.
Auteur(s) : N Baki, RD Eithiraj, H Khachai, R Khenata, G Murtaza, A Bouhemadou, T. Seddik, S Bin-Omran
Mots-clés : Electronic structure, band gap, optoelectronic, FP-LAPW + lo, TB-LMTO
ISSN : 0947-8396 | Vol : 45, N° : 1, pp : 435-443
Résumé : The structural, elastic, electronic, optical and thermodynamic properties of the sodium polonide Na2Po compound have been studied through the full potential linearized augmented plane wave plus local orbitals (FP-LAPW + lo) and tight-binding linear muffin-tin orbital (TB-LMTO) methods. The exchange–correlation potential was treated within the local density approximation for the TB-LMTO calculations and within the generalized gradient approximation for the FP-LAPW + lo calculations. In addition, Tran and Blaha-modified Becke–Johnson (TB-mBJ) potential and Engel–Vosko generalized gradient approximation were used for the electronic and optical properties. Ground state properties such as the equilibrium lattice constant, bulk modulus and its pressure derivative were calculated and compared with available data. The single-crystal and polycrystalline elastic constants of the considered compound were calculated via the total energy versus strain in the framework of the FP-LAPW + lo approach. The calculated electronic structure reveals that Na2Po is a direct band gap semiconductor. The frequency-dependent ielectric function, refractive index, extinction coefficient, reflectivity oefficient and electron energy loss function spectra are calculated for a wide energy range. The variations of the lattice constant, bulk modulus, heat capacity, volume expansion coefficient and Debye temperature with temperature and pressure were calculated successfully using the FP-LAPW + lo method in combination with the quasi-harmonic Debye model.
Auteur(s) : Z. M'hamed
Mots-clés : REGIME DE CHANGE, PAYS ARABES,L’IMPACT DU REGIME DE CHANGE DANS LES PAYS ARABES
ISSN : 2352-9962 | E-ISSN : 2572-0147 | Vol : 2, N° : 2, pp : 7-27
Résumé : Cet article réexamine la contribution du régime de change à la croissance sur la base
d’estimations en données de panel pour 8 pays méditerranéens couvrant la période 1980 à 2013.
Nos estimations valident l’hypothèse d’une influence positive du régime de change sur la
croissance, que ce soit par le biais d’une combinaison de l’accroissement des échanges
commerciaux et du taux d’investissement ou par celui d’un niveau important de l’ouverture
commerciale. Il apparait donc que l’abandon des régimes fixes observé au cours de la dernière
décennie se justifie par un objectif de stabilité de la production.
Auteur(s) : Benounissa Leila& BENABOU Djillali
Mots-clés : اقتصاد المعرفة، الجودة التعليمية، مؤسسات التعليم العالي، معايير التصنيف، الجامعات الجزائرية
E-ISSN : 2602-5183 | Vol : 1, N° : 1, pp : 107-117
Résumé : لقد أصبح الولوج إلى اقتصاد المعرفة ضرورة ملحة بالنسبة لكل دول العالم؛ بحيث يجب أن تهيأ له كل التسهيلات من خلال بناء بنية تحتية تكنولوجية حديثة يعم فيها استخدام الإنترنيت في كافة مجالات الحياة، وكذلك بناء رأسمال بشري قوي من خلال الاهتمام بالتعليم والتكوين المستمر. تعتبر مؤسسات التعليم العالي أهم مراكز تحصيل ونشر المعرفة والتكنولوجياتالحديثة؛ حيث أصبحت جودة هاته المؤسسات من أهم عوامل تمييز الدول في ما يخص اقتصاد المعرفة. وعليه، فإن الهدف من هذا العمل هو الوقوف على العوامل المحددة لجودة مؤسسات التعليم العالي، وكذا المعايير المعتمدة عالميا لتصنيفها، ومحل الجامعات الجزائرية من هذا الواقع الجديد
Auteur(s) : A Bendjedid, T. Seddik, R Khenata, H Baltache, G Murtaza, A Bouhemadou, S Bin Omran, Sikander Azam, Saleem Ayaz Khan
Mots-clés : AmO2; GGA+U+SO; Phase transition; Electronic band-structure; Optical properties
ISSN : 0947-8396 | Vol : 396, pp : 190-197
Résumé : In this work, we have investigated the structural, phase transition, optoelectronic and magnetic properties of AmO2 using the full potential linearized augmented plane wave plus local orbital (FP-LAPW+lo) method. The exchange-correlation potential was treated with the generalized gradient approximation (GGA). Moreover, the GGA+U approximation (where U denotes the Hubbard Coulomb energy U term) is employed to treat the f electrons properly. The structurally stable AmO2 compound is the Fm3m phase and at a pressure between 40 and 60 GPa underwent a phase transition to the Pnma phase. Our present calculations have considered ferromagnetic and simple antiferromagnetic ground states and the AF state is favored. However, the experimental situation suggests a complex magnetic structure, perhaps involving multipolar ordering. Our band structure calculation with GGA and GGA+U predicted the metallic behavior of AmO2; however, with the spin–orbit coupling (SOC) added to the Coulomb energy U term, semiconducting ground states with antiferromagnetism is correctly predicted. The projected density of states from the energy-band structure indicates that the band gap opening is governed by the partially filled Am “5f” state, and the calculated gap is approximately 1.29 eV. Moreover, the optical properties reveal strong response of AmO2 in the UV region.
Auteur(s) : Mohammed Abbes SAHRAOUI, Mostéfa BELMOKADDEM, Mohammed Seghir GUELLIL, Yassine Zakarya GHOUALI
ISSN : 2212-5671 | Vol : 23, pp : 276-290
Auteur(s) : Mohammed Seghir GUELLIL, Mostéfa BELMOKADDEM, Mohammed Abbes SAHRAOUI, Yassine Zakarya GHOUALI
ISSN : 2212-5671 | Vol : 23, pp : 1613–1623
Auteur(s) : Driss Bouguenna*, Nawel Kermas, Bouaza Djellouli
Mots-clés : cubic AlxGa1-xN/GaN, InP/InyGa1-yAs, device simulation, DG MOSFET, DG MOS-HEMT, nextnano3.
ISSN : 2320-3331 | E-ISSN : 2395 -0056 | Vol : 2, N° : 9, pp : 2072-2077
Résumé :
In this paper, we have compared the performance of cubic AlxGa1-xN/GaN and InP/InyGa1-
yAs DG MOS-HEMTs, by analyzing the impact of gate length (LG) using 2D nextnano3 software. Driftdiffusion model was taken for simulating the proposed device. The gate length was varied from (12 to 18) nm in a step of 3 nm. As gate length is reduced for scaling, higher drain current is observed, again as Indium content y of channel layer InyGa1-yAs is increased, there is an increase in drain current density, while threshold voltage is decrease comparable to InP/InyGa1-yAs DG MOS-HEMT. Except drain current density and threshold voltage all other parameters are acceptable, a needful to improve the two parameters. However, the proposed model of cubic AlxGa1-xN/GaN DG MOS-HEMT is the ultimate to replace InP/InyGa1-yAs DG MOS-HEMT and MOSFET for next-generation microwave and power switching application fields in the future.
Auteur(s) : Yassine Zakarya GHOUALI, Mohammed Abbes SAHRAOUI, Mostéfa BELMOKADDEM, Mohammed Seghir GUELLIL
ISSN : 2212-5671 | Vol : 26, pp : 114-125
Auteur(s) : Assia Hebri.
Mots-clés : La responsabilité sociale des entreprises, partie prenantes, le système de management , Sonatrach ,performance globale , système de pilotage .
ISSN : 2253-0363 | Vol : Volume 6, , N° : Numéro 16, , pp : Pages 464-479.
Résumé : Résumé : L objectif de cette étude est de mettre l' accent sur les principes clés des bonnes pratiques de la responsabilité sociale des entreprises et leurs impacts sur la réalisation de sa performances , dans un environnement interne et externe . La mise en place d’un système de management intégré HSE pour le Groupe Sonatrach constitue une priorité absolue du management à différents niveaux. Il s’agit par cette action de mettre en œuvre les engagements de la politique HSE du Groupe. Le processus, déjà entamé, permettra une meilleure évaluation des Performances HSE du Groupe ; et un niveau de comparaison universel .
Auteur(s) : Amina Meliani
Mots-clés : Biofilm, Bioremediation
ISSN : 2352-474X | E-ISSN : 2352-4758 | Vol : 12, pp : 358 of 396
Résumé : With the need of green chemicals and sustainable agroecosystem, biosurfactants’
study and application is becoming imperative.Nowadays,it is known that Rhamnolipids are potent biosurfactants with high potential for bioremediation applications. The elimination of a wide range of pollutants in different ecosystems is an absolute requirement to promote a sustainable development
of our society with low environmental impact. Biological processes play a major role inn the
removal of contaminants and they taken advantage of the astonishing catabolic versatility
of microorganisms to degrade/convert such compounds. The need to remediate these pollutants from contaminated sites has led to the development of effective, economic and environmentally friendly technologies. One of the current strategies used to enhance this process is the application of Pseudomonas PGPR to remediate contaminated soils in association with plants. Of all the present
contaminants, the profound impacts of organic and heavy metal pollutants have attracted worldwide
attention. This review focuses on the progress of PGPR for remediation of soils contaminated with the description of certain mechanisms andstrategies.
Auteur(s) : H. Mekkaoui , A. Yahiaoui, A. Hachemaoui , A. M. Benkouider and Mohammed Belbachir
Mots-clés : Maghnite, Montmorillonite, Catalyst, Epichlorhydrin, Macromonomer, Polyepichlorhydrin, Methacrylic Anhydride.
ISSN : 0975-7384 | Vol : 9, N° : 7, pp : 933-944
Résumé : The polymerization of epichlorhydrin (ECH) catalyzed by Maghnite-H+; (Mag-H+), a montmorillonite sheet
silicate clay exchanged with protons, was investigated. The cationic ring-opening polymerization of epichlorhydrin
was initiated by Mag-H+ at different temperatures ( 20, 30, 40, 50 and 60°C) in bulk and in a solvent. The effects of
the amount of Mag-H+ and the temperature were studi ed. The polymerization rate and the average molecul ar
weights increased with an increase in the temperatu re and the proportion of the catalyst. These result s indicated the
cationic nature of the polymerization and suggested that the polymerization was initiated by proton addition to the
monomer from Mag-H+. Moreover, we used a simple method, in one step in bulk and in solution at room
temperature (20°C), to prepare a telechelic bismacr omonomer: α,ω-bisunsaturated polyepichlorhydrin. The
telechelique polymer was characterized by means of 1H-NMR, FT-IR spectroscopy, UV and GPC
Auteur(s) : K. El Assad Zemallach Ouari, B. Kouskoussa, M. Makha, K. Benchouk, A. Khelil
Mots-clés : Organic solar cells, Indium free, Flexibility, Electrical modelling.
ISSN : 2348-8131 | Vol : 2, N° : 3, pp : 5-11
Résumé : The energy conversion efficiency of indium free flexible organic solar cells based on simple planar CuPc/C60 heterojunction is studied as a function of the anode free properties. The free indium anode consists in a MoO3/Ag/MoO3 multilayer structure. It is shown that the efficiency of the cells is optimized when the Ag film thickness is increased from 11nm to 17 nm. Moreover the best efficiency are achieved when a double anode buffer layer, Au/CuI is introduced between the MoO3/Ag/MoO3 electrode and the CuPc organic layer. Such behaviours are interpreted with the help of a equivalent electrical circuit of the cells. It is shown that, when deposited onto very thin flexible plastic substrate the properties of the MoO3/Ag/MoO3 electrodes are degraded during the realisation of the cell, which justifies the need of thicker Ag film and of the ultra tin Au film.
Auteur(s) : Y.Hachemi, SM.Benslimane
Mots-clés : Web Service Composition; Case Based Planning; User Preferences.
ISSN : 2074-9007 | E-ISSN : 2074-9015 | Vol : 07, N° : 06, pp : 74-82
Résumé : Web service selection is an indispensable process
for web service composition. However it became a difficult
task as many web services are increased on the web and mostly
they offer similar functionalities, which service will be the best.
User preferences are the key to retain only the best services for
the composition. In this paper, we have proposed a web service
composition model based on user preferences. To improve the
process of web service composition we propose a case-based
planning approach with user preferences which uses successful
experiences in past to solve similar problems. In this paper we
integrate user preferences in the phase of selection, adaptation
and planning. Our main contributions are a new method of case
retrieval, an extended algorithm of adaptation and planning
with user preferences. Results obtained offer more than a
solution to the user and taking both functional and nonfunctional requirements.
Auteur(s) : F.Ouadjenia, F. Zahaf , R.Marouf,
Mots-clés : Adsorption; Malachite Green; Kinetic; Silt.
E-ISSN : 978-93-84422-22-6 | pp : 328-334
Résumé : In this work, the potential feasibility of silt dam for removal of malachite green (MG), a cationic dye from aqueous solution was investigated. XRD, MEB and chemical composition analysis were used to characterize the adsorbent material. XRD analysis identified illite as the major clay mineral. The effects of contact time and temperature (298, 303, 313 and 323 K) on the malachite green adsorption have been examined. The results indicated that dye removal was seen to increase with increasing contact time until equilibrium. The experimental isotherm data were analyzed using the Langmuir and Freundlich equations. Data isotherms were good fitted by Freundlich equation. Two kinetic models, the pseudo first order and second-order equations, were selected to follow the adsorption process. Kinetic parameters, rate constants, equilibrium adsorption capacities and correlation coefficients, for each kinetic equation were calculated and discussed. It was shown that the adsorption of malachite green onto adsorbent could be described by the pseudo second-order equation.
Auteur(s) : Z. M'hamed
Mots-clés : Régime de change, croissance économique, données de panel
ISSN : 2170-1083 | E-ISSN : 2600-6138 | Vol : 2, N° : 1, pp : 24-35
Résumé : Cet article réexamine la contribution du régime de change à la croissance sur la base d’estimations en données de panel pour 8 pays méditerranéens couvrant la période 1980 à 2013. Nos estimations valident l’hypothèse d’une influence positive du régime de change sur la croissance, que ce soit par le biais d’une combinaison de l’accroissement des échanges commerciaux et du taux d’investissement ou par celui d’un niveau important de l’ouverture commerciale. Il apparait donc que l’abandon des régimes fixes observé au cours de la dernière décennie se justifie par un objectif de stabilité de la production.
Auteur(s) : Sebane Mounia Aicha
ISSN : 1112-5373 |
Auteur(s) : B. Sid Ahmed, B. Kheloufi , E. Abdelkader
Mots-clés : Pistacia vera L.; biometrics; fruit; kernel; varieties
ISSN : 0975-7384 | E-ISSN : ++++++ | Vol : 7, N° : 4, pp : 1120-1130
Auteur(s) : T.Aicha,M.Catherine B.Mohamed, M.Boumediene
Mots-clés : exopolysaccharides-antioxydant activity- pathogenic bacteria- mentha viridis
ISSN : 0975-7384 | Vol : 7, N° : 6, pp : 90-95
Résumé : Natural extracts contain a variety of phenolic compounds which have an antioxidant and antibacterial capacity;they can successfully replace antibiotics that show their inefficiencies against multi-resistant bacteria. In this context, this study was intended as a contribution to the understanding and evaluation of the bioactive potential of methanolic, hydro-methanolic and aqueous extracts of Mentha viridis. The qualitative analysis revealed the presence of polyphenols and flavonoids, which were confirmed-by-quantitative-analysis. The extracts of Mentha viridis expressed an important anti-production activity of the Exopolysaccharides by all pathogens strains. The amount of exopolysaccharides (EPS) produces by bacteria decreased considerably with all extracts comparatively
to control (without extracts). The extracts showed strong properties to trap molecules of free radical DPPH with an inhibition power ranging from 45 to 85%.
Key words: antibacterial, antioxidant, extracts, Mentha viridis, multi-resistant bacteria
Auteur(s) : Y. Mouchaal, H. Gherras, A. B. Reguig, A. Hachemaoui, A. Yahiaoui, M. Makha, A.Khelil, J-C. Bernede
Résumé : A new material: conjugated poly {(2,5-diyl pyrrole) [4-nitrobenzylid`ene]}, that we called
(PPNB), has been synthesized and characterized. The cyclic voltammetry has been used in order to estimate
first oxidation (Ep) and reduction (En) potentials of our polymer. These values have been assigned,
respectively, to the position of the highest occupied molecular orbital (HOMO) and the lowest unoccupied
molecular orbital (LUMO) and determination of the energy band gap which have been estimated to be 6.16,
3.89 and 2.27 eV respectively.
Auteur(s) : A Djied, T. Seddik, O Merabiha, G Murtaza, R Khenata, R Ahmed, S Bin-Omran, Ş Uğur, A Bouhemadou
Mots-clés : NaZnAs; FP-LAPW+lo; Phase transition; Electronic band structure; Optical properties
ISSN : 0925-8388 | Vol : 622, pp : 812-818
Résumé : In this study, we predict the structural phase transitions as well as opto-electronic properties of the filled-tetrahedral (Nowotny–Juza) NaZnAs compound. Calculations employ the full potential (FP) linearized augmented plane wave (LAPW) plus local orbitals (lo) scheme. The exchange–correlation potential is treated within the generalized gradient approximation of Perdew–Burke and Ernzerhof (GGA-PBE). In addition, Tran and Blaha (TB) modified Becke–Johnson (mBJ) potential is also used to obtain more accurate optoelectronic properties. Geometry optimization is performed to obtain reliable total energies and other structural parameters for each NaZnAs phase. In our study, the sequence of the structural phase transition on compression is Cu2Sb-type → β → α phase. NaZnAs is a direct (Γ–Γ) band gap semiconductor for all the structural phases. However, compared to PBE-GGA, the mBJ approximation reproduces better fundamental band gaps. Moreover, for insight into its potential for photovoltaic applications, different optical parameters are studied.
Auteur(s) : F. Zahaf , R.Marouf, N.Dali , J. Schott
Mots-clés : Bentonite; intercalation; dye; adsorption
Vol : 6, N° : 01, pp : 11-14
Auteur(s) : Benabou Djilali ; Benounissa Leila
Mots-clés : Patents , Economic indicators , Indexes , Production , Investment , Technological innovation
Résumé : Due to the urgent need for the integration of all countries into a new economy; the importance of knowledge and its effective role in advancing the development has accelerated. This is why such economy is known as the knowledge economy. This is what makes us say that we live the transformation from an industry-oriented economy to an knowledge-oriented economy and that the creation of wealth is no longer depending on a physical assets, but it became the basis of all immaterial assets in particular knowledge. In this paper we will try to address the impact of the knowledge economy on the economic growth in Algeria. At first, we tried to present the most important points related to the knowledge economy and then we present the relationship between theories of knowledge economy and the economic growth. As for the practical side, we tried through many indicators and data issued by various specializing organizations, to rate Algeria among a group of countries. We made an analytical and descriptive study, then we studied the relationship between one of these indicators and the GDP, and due to the lack of data for a long time, we took the patents as an indicator to make the causality test.
Auteur(s) : Mokhtar Besseghier; Djebbar Ahmed Bouzidi
Mots-clés : Joint Semi-Blind Estimation
ISSN : 1434-8411 | E-ISSN : 1434-8411 | Vol : 69, N° : 4, pp : 759-764
Résumé : The greatest threat to the OFDM system is the loss of orthogonality between subcarriers due to the carrier frequency offset (CFO) which results in significant performance degradation. In addition to this last problem was the effect of propagation over multipath fading channel. Hence, both the channel and the CFO need to be estimated and corrected at the receiver for subsequent symbol detection. A new joint semi-blind CFO and channel estimation method for OFDM systems operating in multipath fading channels is investigated in this paper. The proposed algorithms are based on virtual subcarriers (VSC) in one hand and on a new design of pilot patterns in OFDM blocks in other hand. We propose to use Newton-Raphson algorithm for the estimation of CFO that has a faster convergence and a lower complexity compared to similar estimators that not employed this algorithm. Finally, we derive the Modified Cramer-Rao bounds (MCRB) for semi-blind CFO and channel estimation to evaluate the performance bounds of the proposed methods for commonly encountered scenarios. The simulation results are given to verify the validity of the proposed methods.
Auteur(s) : M El Amine Monir, H Baltache, G Murtaza, R Khenata, Waleed K Ahmed, A Bouhemadou, S Bin Omran, T. Seddik
Mots-clés : Half-metallic; Magnetic moment B and structure; FP-LAPW; GGA
ISSN : 0304-8853 | Vol : 374, pp : 50-60
Résumé : Based on first principles spin-polarized density functional theory, the structural, elastic electronic and magnetic properties of Zn1−xVxSe (for x=0.25, 0.50, 0.75) in zinc blende structure have been studied. The investigation was done using the full-potential augmented plane wave method as implemented in WIEN2k code. The exchange-correlation potential was treated with the generalized gradient approximation PBE-GGA for the structural and elastic properties. Moreover, the PBE-GGA+U approximation (where U is the Hubbard correlation terms) is employed to treat the “d” electrons properly. A comparative study between the band structures, electronic structures, total and partial densities of states and local moments calculated within both GGA and GGA+U schemes is presented. The analysis of spin-polarized band structure and density of states shows the half-metallic ferromagnetic character and are also used to determine s(p)-d exchange constants N0α (conduction band ) and N0β (valence band) due to Se(4p)–V(3d) hybridization. It has been clearly evidence that the magnetic moment of V is reduced from its free space change value of 3 µB and the minor atomic magnetic moment on Zn and Se are generated.
Auteur(s) : T.Aicha,M; Catherine ,B.Mohamed, M.Boumediene
Mots-clés : Mentha viridis- adhesion- pathogenic bacteria- extract
ISSN : 2320-3358 | Vol : 15, N° : 1, pp : 12-22
Résumé : Micro-organisms do not always exist in planctonic forms (single cells or small groups). To survive, especially in limiting media, they may adhere to inert or living surfaces. This enables them to multiply within a community protected by an extracellular matrix, thus forming a biofilm which protects them from antimicrobials especially antibiotics. In this paper, the aim of this study was to investigate autoaggregation, co-aggragation, surface hydrophobicity and exopolysaccharides production of different pathogenic bacteria treated with methanolic, hydro-methanolic and aqueous extract of Mentha viridis collected in El Bayadh (South West of Algeria). The qualitative analysis revealed the presence of polyphenols and flavonoids, which were confirmed-by-quantitative-analysis. All extracts showed an antibacterial activity (antiadhesiveness).The percentage of autoaggregation, coaggregation decreased in presence of extract comparing to control. E.coli was hydrophobic while the others hydrophilic. The amount of exopolysaccharides (EPS) produces by bacteria decreased considerably with all extracts comparatively to control (without extracts).
Keywords: antiadhesiveness activity, extracts, Mentha viridis, multi-resistant bacteria, polyphenols.
Auteur(s) : R.mounia, D.mohamed, N.abdelkader
Mots-clés : okun's Law, economic growth, unemployment rate, HP filter, ARDL Bounds Testing Approach to Co-integration.
ISSN : 2437-1033 | E-ISSN : 2602-5183 | Vol : 1, N° : 00, pp : 1-17
Résumé : The study provides an estimation of Okun’s law in Algeria during the period (1970 - 2014) using for this purpose time series of techniques. Our empirical analysis consists of Dickey-Fuller test (ADF) (Dickey and Fuller 1979 and 1981), and the Phillips–Perron (1988) test and ARDL Bounds Testing Approach to Co-integration test between unemployment rate and economic growth. The estimated results of the present study conformed existence of stable, long run negative effect juste in one model (the difference version of Okun's law), whereas, in short run no relationship is observed. A one percent increase in economic growth is associated with reduction in the unemployment level by 0.265 percent in the long run. The ECM indicates high speed of adjustment of short run fluctuation as 63 percent short disequilibrium adjusts in a year. Algeria must try to increase and diversify the sources of economic growth. The results of this study have important implications for determining macroeconomic policy. It is absolutely essential that the Algerian economy cease to be excessively dependent on the hydrocarbon sector, which is intensive capital but requires little labour. The Algerian economy should diversify away from its dependence on the energy sector.
Auteur(s) : K. El Assad Zemallach Ouari, Z. El Jouad, K. Benchouk, B. Kouskoussa, L. Cattin, M. Makha, A. Khelil, M. Morsli, M. Addou, J.C. Bernède.
Mots-clés : Interfaces, organic compounds, oxides, vacuum deposition, ageing, electrical properties.
Vol : 52, pp : 829-838
Résumé : The behaviour of small-molecule organic solar cells based on coper-phthalocyanine/fullerene with different cathode buffer layer is investigated as a function of air exposure duration. We present the study of the effect of MoO3 on the properties of photovoltaic solar cells (OPVCs) when it is introduced in the cathode buffer layer (CBL). Photovoltaic performances were measured as a function of time of air exposure. During the first days of air exposure the efficiency of the OPVCs with MoO3 in their CBL increases significantly, while it decreases immediately after air exposure in the case of reference OPVCs, i.e. without MoO3 in the CBL. Nevertheless, the lifetime of the OPVCs with MoO3 in their CBL is around 60 days, while it
is only 10 days in the case of reference OPVCs. The initial increase of the OPVC with MoO3 in their CBL is attributed to the slow decrease of the work function of MoO3 due to progressive contamination. Then, the progressive degradation of the OPVCs efficiency is due water vapour and oxygen contamination of the organic layers. The use of a double CBL, Alq3/MoO3, allows to interrupt the growth of pinholes, defects and increases the path of permeating gas. Also it can prevent the contamination of the organic layer by Al. All this results in significant increase of the lifetime of the OPVCs
Auteur(s) : Mokhtar Besseghier; Djebbar Ahmed Bouzidi; Iyad Dayoub
Mots-clés : Joint Semi-Blind Estimation
ISSN : 0929-6212 | E-ISSN : 1572-834X | Vol : 81, N° : 2, pp : 473-487
Résumé : The large number of subcarriers, used in OFDM systems, increases the sensivity to frequency offset which results from a Doppler shift, due to mobile movement, as well as from a mismatch between the carrier frequencies at the transmitter and receiver. The problem of channel estimation in a practical OFDM receiver that suffers from CFO has been addressed in this paper. We first derived the modified MUSIC based blind CFO estimator. Next, we propose new joint training-based and joint semi-blind CFO and channel estimation for OFDM systems. Whereas the training-based estimator only assumes knowledge of pilot tones, the semi-blind estimator assumes knowledge of the virtual subcarriers (VSCs). For both estimators we derive a maximum likelihood (ML) algorithm for block processing and LMS algorithm for adaptive processing. It is demonstrated that the CFO estimators are able to perform well with a very small number of OFDM blocks. The performance of our estimators was investigated by simulations.
Auteur(s) : Samir Ghouali, Mohammed Feham, Yassine Zakarya Ghouali
Mots-clés : Panel Co-integration, Panel Granger Causality, Cardiorespiratory Hemodynamic signals, Multivariate study, (MGH / MF) waveform database
ISSN : 2320 –3765 | Vol : 03, N° : 11, pp : 13470-13483
Résumé :
In this article, we conducted an investigation using very powerful mathematical model to verify if a long-term relationship exists between Cardiorespiratory hemodynamic signals, the methodology we applied in this paper is mainly based on four basic parts, in first part we applied unit root tests to assess the stationarity of series, the second step is to apply the test of Co-integration model and quantify this long-term relationship. Finally we applied the Granger causality tests to the entire panel that consists of 186 patients taken from Montreal Hospital/General MF (Massachusetts General Hospital/Marquette Foundation) database. The results found in this study show the long-term interaction between the Cardiorespiratory hemodynamic signals, and reveals how the understanding of these interactions can help the doctors to understand the risks that may exist between these interactions.
Auteur(s) : Jihong Xia, Lihuai Lin, Junqiang Lin, Laounia Nehal
Mots-clés : decision support system (DSS); diagnosis; geographic information systems (GIS); river health
ISSN : 2073-4441 | Vol : 6, pp : 3136-3151
Résumé : The development of a decision support system (DSS) to inform policy making
has been progressing rapidly. This paper presents a generic framework and the
development steps of a decision tool prototype of geographic information systems
(GIS)-based decision support system of river health diagnosis (RHD-DSS). This system
integrates data, calculation models, and human knowledge of river health status
assessment, causal factors diagnosis, and restoration decision making to assist decision
makers during river restoration and management in Zhejiang Province, China. Our
RHD-DSS is composed of four main elements: the graphical user interface (GUI), the
database, the model base, and the knowledge base. It has five functional components: the
input module, the database management, the diagnostic indicators management, the
assessment and diagnosis, and the visual result module. The system design is illustrated
with particular emphasis on the development of the database, model schemas, diagnosis
and analytical processing techniques, and map management design. Finally, the application
of the prototype RHD-DSS is presented and implemented for Xinjiangtang River ofHaining County in Zhejiang Province, China. This case study is used to demonstrate the
advantages gained by the application of this system. We conclude that there is great
potential for using the RHD-DSS to systematically manage river basins in order to
effectively mitigate environmental issues. The proposed approach will provide river
managers and designers with improved insight into river degradation conditions, thereby
strengthening the assessment process and the administration of human activities in
river management.
Auteur(s) : Y.Hachemi, SM.Benslimane
Mots-clés : Case-Based Planning, Ontologies, User Preferences, Web Service Composition
ISSN : 1938-0194 | E-ISSN : 1938-0208 | Vol : 06, N° : 04, pp : 58-71
Résumé : Web services composition has emerged as a solution to answer the requester's requirements. However, the selection of an appropriate Web service has become a difficult task due to the number of Web services present on the Web and mostly they offer similar functionalities. User preferences are a key factor that can be used to rank candidate services and retain only the best ones. To improve the process of web service composition the authors propose a Case-Based Planning (CBP) approach based on preferences which uses successful experiences in past to solve similar problems at present or/and in the future. How to make a choice base on non-functional factors becomes a problem that need to be solved. This paper, argues that the selection should be considered in a global manner based on the user's preferences. The authors present a framework that deals with web service composition based on user preferences and CBP method. Results obtained offer more than a solution to the user and taking both functional and non-functional requirements.
Auteur(s) : Samir Ghouali, Mohammed Feham, Yassine Zakarya Ghouali
Mots-clés : Cardiorespiratory Hemodynamic signals; Direction of information; Granger Causality; Multivariate study; (MGH / MF) waveform database
ISSN : 2251-3388 | Vol : 02, N° : 02, pp : 57-66
Résumé :
Auteur(s) : Hamimed, A., Benslimane, M., Khaldi, A., Nehal, L., Zaagane, M
Mots-clés : Remote sensing, triangle concept, energy balance, evapotranspiration, vegetation index, surface temperature, Priestley-Taylor
N° : 18, pp : 179-195
Résumé :
The quantification of evapotranspiration from irrigated areas is important for agriculture water management, especially in arid and semi-arid regions where water deficiency is becoming a major constraint in economic welfare and sustainable development. Conventional methods that use point measurements to estimate evapotranspiration are representative only of local areas and cannot be extended to large areas because of landscape heterogeneity. Remote sensing-based energy balance models are presently most suited for estimating evapotranspiration at both field and regional scales. In this study, we aim to develop a methodology based on the triangle concept, allowing estimation of evapotranspiration through the classical equation of Priestley and Taylor (1972) where the proportional coefficient α in this equation is ranged using a linear interpolation between surface temperature and Normalized Difference Vegetation Index (NDVI) values. Preliminary results using remotely sensed data sets from Landsat ETM+ over the Habra Plains in west Algeria are in good agreement with ground measurements. The proposed approach appears to be more reliable and easily applicable for operational estimation of evapotranspiration over large areas.
Auteur(s) : Hamimed, A., Nehal, L., Khaldi, A., & Azzaz, H
Mots-clés : évapotranspiration, bilan d'énergie, télédétection, Lansdat, METRIC, Algérie
Vol : 8, pp : 197-213
Résumé : L'évapotranspiration est une composante majeure du bilan hydrologique, car elle exprime
les échanges de masse et d'énergie entre le système sol-eau-végétation et l'atmosphère. Sa connaissance
précise est indispensable dans plusieurs applications environnementales, telles que la climatologie,
l'hydrologie et l'agronomie. La télédétection est un outil incontournable pour l'évaluation de
l'évapotranspiration, à la fois dans l'espace et dans le temps.
Dans cette contribution, le modèle de spatialisation METRIC (Mapping EvapoTranspiration at high
Resolution with Internalized Calibration) est appliqué pour l'estimation de l'évapotranspiration d'un
agro-système semi-aride situé dans la plaine du Sersou en Algérie. Deux images du satellite Landsat 7
acquises le 13 mars 2012 et le 30 avril 2012 ont été utilisées. Le modèle METRIC se base sur la
résolution de l'équation du bilan d'énergie à la surface, où l'évapotranspiration est estimée comme le
terme résiduel lorsque le rayonnement net, le flux de chaleur sensible et le flux de chaleur du sol sont
connus. Différents indices d'alimentation en eau de surface dérivés de l'évapotranspiration ont été
ensuite calculés : la fraction d'évapotranspiration de référence, le paramètre de PRIESTLEY-TAYLOR et
la résistance de surface à l'évaporation. Ces indices permettent le diagnostic quantitatif de l'état
hydrique du pixel. Les résultats obtenus concernent la validation du modèle utilisé pour l'analyse de la
distribution spatiale de l'évapotranspiration et des flux énergétiques de surface. En conclusion, les
résultats montrent que le modèle peut être considéré comme une approche prometteuse de spatialisation
de l'évapotranspiration dans le cas des régions où les informations de terrain sont rares ou
difficiles à collecter.
Auteur(s) : A. Larbaoui, B. Belabbes, A. Meroufel, A. Tahour, and D. Bouguenna*
Mots-clés : Backstepping control, Lyapunov theorem, Integral action, Permanent Magnet Synchronous Motor (PMSM), Model Reference Adaptive System (MRAS), observer
ISSN : 2320-3331 | Vol : 9, N° : 4, pp : 59-68
Résumé : The work developed in this article, has aims to control design law is based on Backstepping method to ensure the servo-control of the permanent magnet synchronous motors (PMSM). The slow convergence of adaptation can result, in some cases; irreversible instabilization loop, especially in the presence of nonlinearity and/or couplings. Hence, the Backstepping method coupled with introduction of integral actions is an
alternative choice. Moreover, the Backstepping theory is a recursive design methodology that makes use of the
Lyapunov stability theory. Strong properties of overall and asymptotic stability can be achieved. The second part of this work is a direct application of the control proposed to associate an observer, is the Model Reference Adaptive System (MRAS) to observe the position and the rotor speed of the MRAS. Furthermore, the simulation under the Matlab/Simulink software allows highlighting the performance of the control strategy adopted
Auteur(s) : Assia Hebri.
Mots-clés : Responsabilité sociale des entreprises, partie prenantes, le système de management, Sonatrach, performance globale, système de pilotage
Vol : ????? 1,, N° : ????? 1, , pp : ????? 25-39
Résumé :
La recherche proposée tente d’appréhender l’image de l’entreprise comme le résultat des perceptions et représentations des différentes parties prenantes au sujet du rôle et de l‘impact qu‘exerce l’entreprise sur ces mêmes acteurs et la participation de ses acteurs dans la réalisation de la performance dans leur sens globale. L’hypothèse sous-jacente postule que chaque catégorie d’acteur possède une manière propre d’interpréter les caractéristiques de l’activité en fonction de ses propres contraintes et intérêts. Sur cette base, ces acteurs élaborent une représentation particulière de l’entreprise qu’ils tentent de diffuser afin de rallier d’autres catégories d‘acteurs à leurs points de vue..
Auteur(s) : G Murtaza, SK Gupta, T. Seddik, R Khenata, ZA Alahmed, R Ahmed, H Khachai, PK Jha, S Bin Omran
Mots-clés : FP-APW + lo; Electronic properties; Optical properties; Thermodynamic properties
ISSN : 0925-8388 | Vol : 597, pp : 36-44
Résumé : Structural, elastic, optoelectronic and thermodynamic properties of REGa3 (RE = Sc and Lu) compounds have been studied self consistently by employing state of the art full potential (FP) linearized (L) approach of augmented plane wave (APW) plus local orbitals method. Calculations were executed at the level of Perdew–Burke and Ernzerhof (PBE) parameterized generalized gradient approximation (GGA) for exchange correlation functional in addition to modified Becke–Johnson (mBJ) potential. Our obtained results of lattice parameters show reasonable agreement to the previously reported experimental and other theoretical studies. Analysis of the calculated band structure of ScGa3 and LuGa3 compounds demonstrates their metallic character. Moreover, a positive value of calculated Cauchy pressure, in addition to reflecting their ductile nature, endorses their metallic character as well. To understand optical behavior calculations related to the important optical parameters; real and imaginary parts of the dielectric function, reflectivity R(ω), refractive index n(ω) and electron energy-loss function L(ω) have also been performed. In the present work, thermodynamically properties are also investigated by employing lattice vibrations integrated in quasi harmonic Debye model. Obtained results of volume, heat capacity and Debye temperature as a function of temperature for both compounds, at different values of pressure, are found to be consistent. The calculated value of melting temperature for both compounds (ScGa3 and LuGa3) is found to be similar to the experimental data with an underestimation of 5%.
Auteur(s) : Benounissa Leila
Mots-clés : المعرفة، اقتصاد المعرفة، مؤشرات اقتصاد المعرفة، النمو الاقتصادي، الجزائر، دراسة قياسية
ISSN : 2600-6197 | Vol : 5, N° : 1, pp : 86-93
Résumé : ظرا للضرورة الملحة لاندماج كل الدول نحو اقتصاد جديد ازدادت فيه اهمية المعرفة و دورها الفعال في دفع عجلت التنمية واصبحت مقياسا للثروة اذا سمي هذا الاقتصاد "باقتصاد المعرفة" هذا ما يدفعنا للقول أن التحول من اقتصاد مقاد بواسطة الصناعة الى اقتصاد مدار بواسطة المعلومات و المعارف و يدفعنا للقول أن خلق الثروة لم يعد وفق سياق مادي، بل أصبح مبني على كل ما هو غير مادي وموجه خصوصا بواسطة المعرفة سنحاول في هذه الورقة معالجة أثر اقتصاد المعرفة و النمو الإقتصادي (دراسة حالة الجزائر) في البداية حاولنا معرفة أهم النقاط النظرية المتعلقة باقتصاد المعرفة، ثم ننتقل إلى نقطة مهمة أخرى وهي النظريات الرابطة بين اقتصاد المعرفة و النمو الاقتصادي. أما في الجانب التطبيقي فحاولنا من خلال العديد من المؤشرات والمعطيات الصادرة من مختلف الهيئات والمنظمات المتخصصة تصنيف الجزائر ضمن مجموعة من الدول. وقمنا بدراسة تحليلية ثم دراسة العلاقة بين أحد هذه المؤشرات و الناتج المحلي الإجمالي، لعدم توفر المعطيات لفترة زمنية طويلة اخذنا براءات الاختراع كمؤشر لاختبار السببية.
Auteur(s) : Abdelmadjid. Benmohammed, Omar. Khoumeri, Ayada. Djafri, Thierry. Terme, Patrice. Vanelle
Mots-clés : 4-phenyl-3-thiosemicarbazones, thiazolidinones
ISSN : 1420-3049 | Vol : 19, N° : 3, pp : 3068–3083
Auteur(s) : A Djied, H Khachai, T. Seddik, R Khenata, A Bouhemadou, N Guechi, G Murtaza, S Bin-Omran, ZA Alahmed, M Ameri
Mots-clés : NaZnP; FP-APW + lo; Phase transition; Elastic constants; Electronic properties; Optical properties
ISSN : 0927-0256 | Vol : 84, pp : 396-403
Résumé : Ab-initio full potential augmented plane wave plus local orbitals method has been used to investigate the structural phase transition, mechanical and optoelectronic properties of the Nowotny–Juza filled-tetrahedral compound NaZnP. The exchange-correlation potential was treated within the generalized gradient approximation of Perdew–Burke and Ernzerhof (GGA-PBE) and the modified Becke–Johnson potential (TB-mBJ) to improve the accuracy of the electronic band structure. Total-energy and geometry optimizations have been carried out for all structural phases of NaZnP. The following sequence of pressure-driven structural transitions has been found: Cu2Sb-type → β-phase → α-phase. The single-crystal elastic constants of NaZnP in the Cu2Sb-type structure have been calculated using total-energy versus strain method and their corresponding elastic moduli of polycrystalline aggregate, including Young’s modulus, shear modulus and Poisson’s ratio, have been derived. From the elastic parameters, it is inferred that this compound is brittle in nature. The elastic anisotropy was studied in detail using three different indexes; especially the 3D direction dependence of the Young’s modulus was visually described. Furthermore, calculated electronic band structure shows that NaZnP in the Cu2Sb-type phase has a direct energy band gap (Γ–Γ). The TB-mBJ approximation yields larger fundamental band gaps compared to those of PBE-GGA. The examined charge density distributions for the Cu2Sb-type structure show a covalent character for Zn–P bond and ionic nature for Na–P bond. Additionally, real and imaginary parts of the dielectric function, reflectivity and energy loss function spectra have been calculated for radiation up to 30.0 eV with an incident radiation polarized parallel to both [1 0 0] and [0 0 1] crystalline directions.
Auteur(s) : O Merabiha, T. Seddik, R Khenata, G Murtaza, A Bouhemadou, Y Takagiwa, S Bin Omran, D Rached
Mots-clés : FP-APW + lo; GGA, GGA + U; Magnetic properties; Electronic properties; Thermodynamic properties
ISSN : 0925-8388 | Vol : 586, pp : 529-535
Résumé : Structural, magnetic, electronic and thermodynamic properties of the hexagonal U3ZrSb5 are theoretically investigated by using the full potential linearized augmented plane wave plus local orbital’s (FP-LAPW + lo) method. The exchange–correlation potential was treated with the generalized gradient approximation GGA of Wu and Cohen. Moreover, the GGA + U approximation (where U is the Hubbard correlation terms) is employed to treat the f electrons properly. The calculated structural parameters are in good agreement with the experimental data. The magnetic study reveals that U3ZrSb5 is a ferromagnetic material. Furthermore, we present a comparative study between the band structures, electronic structures, total and partial densities of states and local moments calculated within both GGA and GGA + U schemes. Our band structure calculations show the metallic behavior of this ferromagnetic compound. The thermodynamic properties are predicted through the quasi-harmonic Debye model, in which the lattice vibrations are taken into account. The variation of relative change in volume, heat capacities and the Debye temperature with temperature and pressure are successfully achieved.
Auteur(s) : M Ould Kada, T. Seddik, Adlane Sayede, R Khenata, A Bouhemadou, E Deligoz, ZA Alahmed, S Bin Omran, D Rached
Mots-clés : Intermetallics; electronic structure; mechanical properties; thermodynamic properties; ab initio calculations
ISSN : 0217-9792 | Vol : 28, N° : 3, pp : 1450006
Résumé : Structural, electronic, elastic and thermodynamic properties of Rh3X(X = Zr, Nb, Ta) intermetallic compounds are investigated in the framework of density functional theory (DFT). The exchange-correlation (XC) potential is treated with the generalized gradient approximation (GGA) and local density approximation (LDA). The computed ground state properties agree well with the available theoretical and experimental values. The elastic constants are obtained by calculating the total energy versus volume conserving strains using Mehl model. The electronic and bonding properties are discussed from the calculations of band structures (BSs), densities of states and electron charge densities. The volume and bulk modulus at high pressure and temperature are investigated. Additionally, thermodynamic properties such as the heat capacity, thermal expansion and Debye temperature at high pressures and temperatures are also analyzed.
Auteur(s) : A Missoum, T. Seddik, G Murtaza, R Khenata, A Bouhemadou, Y Al-Douri, A Abdiche, H Meradji, H Baltache
Mots-clés : FP-LAPWGGA; Structural properties; half-Heusler
Vol : 92, N° : 10, pp : 1105-1112
Résumé : To study the structural, electronic, and optical properties of the half-Heusler CoCrZ (Z = Al, Ga), we have performed ab initio calculations using the full-potential with the mixed basis (APW + lo) method within the generalized gradient approximation. The structural properties as well as the band structures, and total and atomic projected densities of states are computed. From electronic band structures we have found that both compounds have a semimetallic nature. We also studied the evolution of electronic structure of CoCrAl under external hydrostatic pressure. It is found that the pseudo gap around the Fermi level increases continuously with increasing pressure, while the electronic density of states at the Fermi level does not change significantly. Furthermore, the optical properties, such as the dielectric function and refractive index were evaluated and discussed under pressure up to 20 GPa, and the electrical conductivity and electron energy loss were calculated for radiation up to 30 eV. The same way, we have studied the magnetic properties of CoCrAl for lattice expansion up to a = 1.1a0 where a transition from the paramagnetic phase to the half-metallic phase is expected.
Auteur(s) : Mostéfa BELMOKADDEM, Yassine Zakarya GHOUALI, Mohammed Seghir GUELLIL, Mohammed Abbes SAHRAOUI
ISSN : 2212-5671 | Vol : 3, N° : 2, pp : 1-30
Auteur(s) : Mostéfa BELMOKADDEM, Yassine Zakarya GHOUALI, Mohammed Seghir GUELLIL
ISSN : 2067 – 9459 | Vol : 5, N° : 19, pp : 49-62
Auteur(s) : Jihong Xia, Launia Nehal
Mots-clés : riparian zone; flexible aquatic vegetation; ecohydraulics; Manning coefficient n; vertical velocity; turbulence
ISSN : 2073-4441 | Vol : 5, N° : 4, pp : 2080-2093
Résumé : Vegetation in riparian zones has a significant influence on resistance, velocity
distribution and turbulence intensity. This study experimentally investigated the effect of
emergent bending riparian zone vegetation on the flow. The results showed that the frond
and stem parts of Acorus calami had different influences on hydraulic features and that the
relative depth ratio of water depth h to stem height hs was a key determinant of those
influences. Manning coefficient n varied greatly with the variation of vegetation densities,
relative depth ratio of water depth h to stem height hs, Re and Fr. Manning coefficient n
increased with increasing vegetation density, particularly in cases when h/hs > 1. The
velocity distributions did not follow logarithmic profiles, but they instead exhibited double
logarithmic profiles. In addition, vegetation characteristics were shown to influence the
height of maximum velocity. The position of maximum velocity is further away from the
bed in cases with denser vegetation distribution. Finally, turbulence intensity showed more
significant variation in the stem part and peaked near the middle of the stem, at z/hs = 0.5,
where z was the distance from the bottom.
Auteur(s) : T. Seddik, R Khenata, A Bouhemadou, N Guechi, Adlane Sayede, Dinesh Varshney, Y Al-Douri, AH Reshak, S Bin-Omran
Mots-clés : Yttrium monochalcogenides; FP-LAPWGGA; Structural properties; Elastic constants; Thermodynamic properties
ISSN : 0921-4526 | Vol : 428, pp : 78-88
Résumé : The full potential linearized augmented plane wave method within the framework of density functional theory is employed to investigate the structural, thermodynamic and elastic properties of the yttrium chalcogenides (YX: X=S, Se, and Te) in their low-pressure phase () and high-pressure phase (). The exchange-correlation potential is treated with the generalized gradient approximation of Perdew–Burke–Ernzerhof (GGA-PBE). Temperature dependence of the volume and both adiabatic and isothermal bulk moduli is predicted for a temperature range from for the both phases of the herein considered materials. Furthermore, we have analyzed the thermodynamic properties such as the heat capacities, CV and CP, thermal expansion, α, and Debye temperature, ΘD, under variable pressure and temperature. We have calculated the isothermal elastic constants CijT of the YX monochalcogenides in both NaCl-B1 and CsCl-B2 phases at zero pressure and a temperature range . The results show that rare earth yttrium monochalcogenides are mechanically stable at high temperature. The elastic anisotropy of all studied materials in the two phases has been studied using three different methods.
Auteur(s) : Driss Bouguenna*, A. Boudghene Stambouli, A. Zado, D.J. As, N. Mekkakia Maaza,
Mots-clés : Cubic AlxGa1−xN/GaN, NanostructuresDevice simulationMODFETMOS-MODFETNextnano3
ISSN : 0749-6036 | E-ISSN : 1096-3677 | Vol : 62, pp : 260-268
Résumé : We report some comparative results on cubic AlxGa1−xN/GaN nanostructures MODFET and MOS-MODFET. The drain current characteristics of cubic AlxGa1−xN/GaN MODFET and MOS-MODFET are simulated by changing the different device parameters such as Al content x and the cubic GaN buffer layer thickness using 2D nextnano3 numerical simulation software. Drift–diffusion model has taken for simulating the proposed device. These results clearly indicate that the transistor simulation with 5 nm isolator SiO2 layer thickness under the gate, Al content of x = 25% and 200 nm cubic GaN buffer layer thickness shows the tremendous I–V characteristics. Also, this structure shows an increase of the drain saturation current and a decrease in the threshold voltage. Moreover, our simulation results exhibited lower threshold voltage and higher drain current density of MOS-MODFET is a factor 30% higher than the same current of a conventional MODFET. The MODFET with 5 nm isolator SiO2 layer thickness has been much better performance. To avoid current flow through the high conductive 3C-SiC substrate a 150 nm p-doped cubic GaN layer is deposited. A comparison between our experimental and simulation results are shown to be in good agreement for cubic Al0.25Ga0.75N/GaN nanostructures MOS-MODFET. The demonstrated MOS-MODFET will be attractive for the next-generation microwave and high power switching application fields.
Auteur(s) : BELDJILALI gherici, BELKHELFA mohamed, HASNI abdelbasset
Mots-clés : Four-dimensional Pseudosymmetric Kahlerian Manifolds, Ricci tensor
ISSN : 2277-5129 | Vol : 2, N° : 4, pp : 1-6
Résumé : In the present paper, we prove that for a 4-dimensional properly pseudosymmetric Kählerian manifold M, the Ricci tensor vanishes on the set p in {M/ f(p) 6≠ 0} where f is the structure function (i.e R(X,Y ) = f(XÙY).R) and for f > 0 the manifold is not compact. Various examples are discussed.
Auteur(s) : Hamimed, A., Nehal, L., Benslimane, M., Khaldi, A
Mots-clés : emergent vegetation, density, Manning resistance coefficient, Drag
ISSN : 1112-3680 | N° : 15, pp : 55-63
Résumé : Vegetation growing in the water along rivers has been the subject of several studies since it was recognized that it could have a significant impact on the water flow. It may increases resistance to flow and causes higher water levels. Also, it has affects on the turbulent structure such as the mean velocity profiles. For flow of water through emergent vegetation, previous investigations show different results. Hence, better knowledge on its impact on flow conditions is needed. The purpose of this paper is to investigate, how density and placement of emergent vegetation influence flow resistance, water depth and velocity profile. Experiments using artificial vegetation selected to simulate emergent vegetation were carried out in a laboratory flume instead of natural channel, and Manning’s n is used to denote the resistance coefficient. The results show large variations in the Manning resistance coefficient with depth of flow and vegetative density. Vegetation causes resistance to flow; it reduces flow velocities and increases water depth. For the vegetation densities considered, the presence of foliage significantly reduces the mean velocities. Also mean velocity profile is set by the vertical structure of the vegetative drag.
Auteur(s) : Assia Hebri.
Mots-clés : responsabilité sociale des entreprises, partie prenantes, le système de management, Sonatrach, performance globale, système de pilotage
ISSN : 2067 - 9459 | Vol : , N° : 02 / 2013 , pp : 79-86
Résumé : La réalisation de la performance globale d’une entreprise, résulte de l’état d‘un
rapport de force entre différentes manières de présenter et se représenter la place de
l‘entreprise sur diverses échelles d’évaluation propres à chaque groupe d‘acteurs. La
première étape dans l’opérationnalisation de cette approche par les parties prenantes
consiste à identifier les différentes catégories d’acteurs à prendre en compte dans l’analyse.
On va donc regroupé ses parties prenantes, dans les six grandes catégories influents sur
la réalisation de la performance de l’entreprise étudié, ils sont: les clients, la communauté
locale et la société civile, les fournisseurs, l’environnement, la flexibilité organisationnelle
et l’adaptation au changement, les employés
Auteur(s) : Z. M'hamed
Mots-clés : MENA countries, exchange rate change, economic growth, panel data
ISSN : 1112-6132 | E-ISSN : 2588-1930 | Vol : 9, N° : 11, pp : 1-21
Résumé : This paper examined the empirical relationship between the
exchange rate regime and economic growth using pane data
regressions for 8 countries in the Middle East and North Africa
(Algeria, Egypt, Iran, Jordan, Lebanon, Morocco, Syria and Tunisia)
for the period 1980-2012. The main results are: the exchange rate
regime appears to affect economic growth through a combination of
increased foreign trade and investment rate but with a weights higher
degree of openness to international trade.
Auteur(s) : Assia Hebri.
Mots-clés : / سوناطراك/الأخطار المهنية /استثمارات طوير حصة الأمن و السلامة في العمل
Vol : ?????? 1, , N° : ????? 1, , pp : ?????? 263-297
Résumé : لقد ساهمت الديناميكية العميقة و المنسجمة لمجمع سوناطراك و التي تتضمن إضافات و استثمارات جديدة كل عام في تطوير حصة الأمن و السلامة في العمل خلالها و الاهتمام الكبير بالبيئة . يتضمن هذا البحث إستراتيجية المجمع المبنية على اهتمامه في الفترة الأخيرة بتخفيض منحنيات الكوارث و الحوادث التي تمس مواقع العمل و العمال بها ، فقد حقق المجمع انخفضا في معدلات شدة الإصابة و تكرار الحوادث خلال الفترة الأخيرة و هذا كان بفضل انطلاق العمل بنظام الأمن و الصحة و البيئة، ليعزز السياسة الوقائية بالمجمع ، و هو نظام مؤسس و مهيكل مكن من تحديث و انسجام طرق التسيير في مجال الأمن و هذا ما يشكل إيجابيات لكل عمال المجمع و ما يرسي ثقافة خاصة للأمن داخله.
Auteur(s) : Mostefa BELMOKADDEM, Sidi Mohamed Boumediene KHETIB, Mohammed Seghir GUELLIL
Mots-clés : oil economy, OAPEC, macro-econometric modeling, trajectory of GDP, oil production, analysis of panel data, economic growth
Vol : 2, N° : 1, pp : 31-50
Auteur(s) : بن مصمودي علي
Mots-clés : البلوغ، مداخل تدريس التربية الجنسية،
ISSN : 2009-5129 | N° : 16, pp : 181-190
Résumé : كيف يمكن ان ندرس التربية الجنسية بدون اثارة الغرائز بحيث يتم ذلك بصورة علمية
Auteur(s) : T.Aicha,M.Catherine, A. Abdelkader ,M.Boumediene
Mots-clés : Salvadora persica- enfants scolarisés- antimicrobial activity- in vitro- in vivo
ISSN : 0378-8741 | Vol : 144, pp : 57-66
Résumé : Ethnopharmacological relevance: Salvadora persica L. (miswak) is traditionally used to ensure oral
hygiene Muslim people in developing countries where it is growing. The antibacterial properties of
Salvadora persica L. originating from various geographic areas have already been reported. However,
they have never been tested for samples originating from Hoggar, where extreme weather conditions
could lead to different properties for this Salvadora persica L. ecotype.
Aim of the study: To assess the in vitro and in vivo antimicrobial activities of methanolic extract of
Algerian Hoggar Salvadora persica L. (miswak) on some isolated and identified strains from the oral
cavity of school children aged from 6 to 12 with (n¼20) and without (n¼20) caries.
Materials and methods: After a qualitative and quantitative analysis of dental plaque samples from the
selected children, the effect of methanolic extract of Hoggar miswak against oral bacterial and fungal
strains isolated from the oral cavity of children with caries was tested by both agar disc diffusion and microdilution methods. The stability and physicochemical parameters of Hoggar Salvadora persica L.
mouthwash were also assessed compared. The in vivo antimicrobial effect of Hoggar miswak rinse on
dental plaque samples was also tested over a week.
Results: Four bacterial genera (Staphylococcus, Streptococcus, Escherichia and Lactobacillus) were commonly identified in all subjects at different colonization levels. A statistically significant difference in colonization levels between the two groups of children was recorded. Hoggar miswak extract more significantly inhibited the growth of Gram negative bacteria from the dental plaque than Gram positive ones. Hoggar Salvadora persica L. mouthwash was stable at 4 1C and 25 1C over the period of conservation (one week) while a temperature of 40 1C induced variations in the physicochemical
parameters and considered not suitable for preservation. The in vivo study revealed a significant
reduction in bacteria of the oral cavity using miswak mouthwash as compared to placebo.
Conclusion: Hoggar miswak extract displayed a strong antimicrobial effect both in vitro and in vivo. Its use as a mouthrinse could therefore be recommended as a preventive measure to preserve from
tooth decay.
Auteur(s) : Driss Bouguenna*, A. Boudghene Stambouli, A. Zado, D.J. As, N. Mekkakia Maaza,
Mots-clés : Cubic AlxGa1-xN/GaN, MODFET, Δ-doping, Drain Current, Threshold Voltage, Nextnano3
ISSN : 1844-6035 | E-ISSN : 2067-2128 | Vol : 2, N° : 5, pp : 309-315
Auteur(s) : T. Seddik, R Khenata, A Bouhemadou, D Rached, Dinesh Varshney, S Bin-Omran
Mots-clés : A. Alkali metal chalcogenides B. FP-L/APW + lo method D. Structural properties D. Elastic constants D. Electronic properties
ISSN : 0927-0256 | Vol : 61, pp : 206-212
Résumé : The structural, electronic and elastic properties of the tetragonal alkali metal chalcogenides KLiX [X: S, Se and Te] have been investigated using the full-potential (linearized) augmented plane wave plus local orbitals method. The exchange–correlation potential is treated within the generalized gradient approximation of Wu and Cohen. Moreover, the alternative form of GGA proposed by Engel and Vosko is also used for the electronic properties. The calculated structural parameters are in excellent agreement with the experimental data. The elastic constants Cij are predicted using the total energy variation versus strain technique. The polycrystalline elastic moduli, namely; shear modulus, Young’s modulus, Poisson’s ratio, sound velocities and Debye temperature are derived from the obtained single-crystal elastic constants. Brittleness behavior of these compounds is interpreted via the calculated elastic constants Cij. Calculated band structures show that KLiS and KLiSe have an indirect energy band gap, whereas KLiTe has a direct energy band gap. The contribution of alkali metals and chalcogen atoms to the electronic band structure and electronic density of states has been analyzed. This is the first quantitative theoretical prediction of the elastic and electronic properties for these investigated compounds and still awaits experimental confirmations.
Auteur(s) : T. Seddik, R Khenata, O Merabiha, A Bouhemadou, S Bin-Omran, D Rached
Mots-clés : Ab initio calculation; FP-APW + lo; Structural properties; Elastic constants
ISSN : 0947-8396 | Vol : 106, N° : 3, pp : 645-653
Résumé : The elastic, electronic and thermodynamic properties of fluoro-perovskite KZnF3 have been calculated using the full-potential linearized augmented plane wave (FP-LAPW) method. The exchange-correlation potential is treated with the generalized gradient approximation of Perdew-Burke-Ernzerhof (GGA-PBE). Also, we have used the Engel and Vosko GGA formalism (GGA-EV) to improve the electronic band structure calculations. The calculated structural properties are in good agreement with available experimental and theoretical data. The elastic constants C ij are calculated using the total energy variation with strain technique. The shear modulus, Young’s modulus, Poisson’s ratio and the Lamé coefficients for polycrystalline KZnF3 aggregates are estimated in the framework of the Voigt-Reuss-Hill approximations. The ductility behavior of this compound is interpreted via the calculated elastic constants C ij . Electronic and bonding properties are discussed from the calculations of band structure, density of states and electron charge density. The thermodynamic properties are predicted through the quasi-harmonic Debye model, in which the lattice vibrations are taken into account. The variation of bulk modulus, lattice constant, heat capacities and the Debye temperature with pressure and temperature are successfully obtained.
Auteur(s) : H. Gherras, A. Hachemaoui, A. Yahiaoui, A. Benyoucef, A.Belfedal, M.Belbachir
ISSN : 03796779 |
Auteur(s) : بن مصمودي علي
Mots-clés : الضغط النفسي الحالي، الضغط النفسي المت
N° : 07, pp : 74-81
Résumé : اهم الاستراتيجيات التي يستخدمها الفرد لمواجهة الضغوط النفسية
Auteur(s) : T. Seddik, R Khenata, A Bouhemadou, Ali H Reshak, F Semari, B Amrani
Mots-clés : Yttrium chalcogenides, Ab initio calculation; FP-APW + lo; Structural properties; Phase transition; Elastic constants
ISSN : 0921-4526 | Vol : 49, N° : 2, pp : 394-399
Résumé : The full-potential linearized augmented plane-wave plus local orbitals method with the generalized gradient approximation for the exchange–correlation potential (FP-APW + lo-GGA) is used to predict the structural, elastic and high pressure properties of YX with X = S, Se and Te. Ground state properties such as lattice constant, bulk modulus and its pressure derivative are obtained. The pressures at which these compounds undergo structural phase transition from NaCl-type to CsCl-type phases are calculated. The elastic constants and their pressure dependence are calculated using the total energy variation with strain technique. The shear modulus, Young’s modulus, Poisson’s ratio and Lamé’s coefficients are estimated in framework of Voigt–Reuss–Hill approximation for polycrystalline YX aggregates. The Debye temperature is estimated from the average sound velocity. To our knowledge this is the first quantitative theoretical prediction of the elastic and high pressure properties for these compounds and still awaits experimental confirmations.
Auteur(s) : T Seddik, F Semari, R Khenata, A Bouhemadou, B Amrani
Mots-clés : Lutetium chalcogenidesAb initio calculationFP−APW+loStructural propertiesPhase transitionElastic constants
ISSN : 0921-4526 | Vol : 405, N° : 1, pp : 394-399
Résumé : Using first-principles density functional calculation, the pressure-induced structural phase transformation and mechanical properties of NaCl type (B1) structure in Lutetium chalcogenides (LuX: X=S, Se, Te) were studied by means of the full-potential augmented plane wave plus local orbitals (FP−APW+lo) method. The calculations were performed within the generalized gradient approximation (GGA) for the exchange-correlation potential. The calculated ground-state properties such us lattice constants agree quit well with the experimental findings. We have determined the full set of first-order elastic constants and their pressure dependence, which have not been calculated and measured yet. The Debye temperature is estimated from the average sound velocity. To our knowledge this is the first quantitative theoretical prediction of the structural phase transition and elastic properties for these compounds and still awaits experimental confirmations.
Auteur(s) : K. Benchouk; K. Zamallach; A. Khelil; J.C. Bernede
Vol : 13, pp : 01-04
Résumé : Thin films of CuAlTe2 were elaborated by a sequential deposition of three elements
Cu; Al and Te under secondary vacuum on glass slides followed by an annealing of 1/2 hour in
an open tube within argon atmosphere. The X-rays diffraction diagram depicts a (112)
preferential orientation and the presence of low intensities peaks characterizing the
chalcopyrite structure. This shows that the majority of crystallites are directed towards the
(112) direction with an orientation factor having an approximate value of 70 %. The height of
the crystallites has been assessed using a scanning electron microscope and found to be larger
than 200nm.
Auteur(s) : Y.Hachemi, B.Malki, D.Amar Bensaber
Mots-clés : Web Service Composition; MDA
Vol : 02,
Résumé : Currently, Web services are available on Internet in a simple and easy way to use. However, a single service can not respond to a predetermined request by user. Thus, it is necessary to compose services, ie, organize them in a manner to achieve the goal automatically. The semantic web services increases the descriptions of web services using semantic annotations (eg ontology). There are different approaches to express the semantic aspect as OWL-S, WSMO, WSDL-S and a recent W3C recommendation SAWSDL (Semantic Annotations for WSDL and XML Schema). To address complexity, scalability and heterogeneity problems of Web Systems, the OMG has proposed the model driven approach MDA based on the concepts of models, metamodels and transformations. The method describes a process that guides the developer through various phases, starting with the models, and ending with a new compound that can be deployed and published.
Auteur(s) : A Bouhemadou, R Khenata, M Kharoubi, T. Seddik, Ali H Reshak, Y Al-Douri
Mots-clés : III-P compoundsFP-APW + loElastic moduliPressure effect
ISSN : 0927-0256 | Vol : 45, N° : 2, pp : 474-479
Résumé : The effect of high-pressures on the structural and elastic properties of XP zinc-blende compounds, with X = B, Al, Ga and In, has been investigated using the full-potential augmented plane wave plus local orbitals method within density functional theory. The bulk properties, including lattice constant, bulk modulus and its pressure derivative are obtained. The elastic constants and their pressure dependence are calculated using total energy variation with strain technique. We derived the bulk modulus, shear modulus, Young’s modulus and Poisson’s ratio for ideal polycrystalline XP aggregates. We estimated the Debye temperature of XP compounds from the average sound velocity. Our results are in reasonable agreement with the available theoretical and experimental data.
Auteur(s) : H.leila.
Mots-clés : obligation de reseve
ISSN : 2352-9784 | N° : 03, pp : 113-120
Auteur(s) : NEHAL Laounia , YAN Zhong min , XIA Ji hong
Mots-clés : open channel flow , nonsubmerged vegetation , vegetation density , flow resistance , velocity distribution
ISSN : 1001-6058 | Vol : 17, N° : 4, pp : 498-502
Résumé : Vegetation is an important feature of many rivers. Vegetation along rivers
produces high resistance to flow and, as a result, has a large impact on water
levels in rivers and lakes. The effects of instream-unsubmerged vegetation
(such as the reed-similar Kalmus) on flow resistance and velocity distributions is
studied in the paper. Artificial vegetation is used in the experimental study to
simulate the Acorus Calmus L. As shown in experimental tests the resistance
depends strongly on vegetation density and the Manning resistance coefficient
varies with the depth of flow. A simplified model based on concepts of drag is
developed to evaluate the roughness coefficient (Manning's n) for nonsubmerged
vegetation. In vegetated channels the overall flow resistance is
influenced significantly by the distribution pattern of the vegetated beds. Within
vegetation, vertical variation in velocity is different from that in the nonvegetated
bed, which reflects the variation in vegetation density. Vertical
turbulent transport of momentum is negligible as demonstrated by experiments.
Auteur(s) : لقام عبد الكريم بوجلال و الهلة محمد
ISSN : ?.?.?.? 978 ?9931 ? 9612 ? 5 ? 3 |
Résumé : كتاب جماعي: نشر بحث المعنون بـ "دور العينة في عملية جمع بيانات البحث العلمي" في كتاب جماعي محكم، ذو ترقيم دولي الموسوم بـ "الدليل المنهجي في إعداد المذكرات و الرسائل الجامعية في العلوم الإقتصادية ، العلوم التجارية و العلوم التسيير بين التأصيل العلمي و الممارسات التطبيقية". كلية العلوم الإقتصادية والتجارية و العلوم التسيير بالتعاون مع مخبر الدراسات و البحوث في التنمية الريفية. جامعة "محمد البشير الإبراهيمي" ـ برج بوعريرج ـ ر.د.م.ك 978 ـ9931 ـ 9612 ـ 5 ـ 3 ISBN ـ الجزائر.
Auteur(s) : Habib Bouzir, Gherici Beldjilali
Vol : June 2021, N° : ol.26, No.2, 2021,
Résumé : o equip a space with a structure leads to the production of a new mathemati-cal object and consequently to contribute to the development of science. Manifoldsequipped with certain differential-geometric structures are richer and more practicalspaces, they have been studied widely in differential geometry. Indeed, D. Chinea andC. Gonzalez [1] obtained a classification of the (2n + 1)-dimensional almost contactmetric manifold based onU(n) representation theory, which is an analogy of the clas-sification of the 2n-dimensional almost Hermitian manifolds established by A. Grayand H. M. Hervella [4].
(PDF) Almost Hermitian Golden manifolds. Available from: https://www.researchgate.net/publication/352569218_Almost_Hermitian_Golden_manifolds [accessed Aug 06 2021].
Auteur(s) : Habib Bouzir
N° : 2019,
Auteur(s) : H. Gherras, A. Hachemaoui, A. Yahiaoui, M. Belbachir , A. Belfedal
Résumé : A new poly (heteroary1ene methylene) containing one to four -pyrrole rings alternating with an sp3-carbon atom in the main chain were synthesized and characterized. The synthesized poly [(pyrrole-2, 5-diyl)-co-(4-nitrobenzylidene)] was found to be highly dehydrogenated, thus resulting in black materials with conjugated segments larger than a single pyrrole ring. The conjugated polymers containing alternating aromatic and quinoid heteroarylene moieties in the main chain were prepared by polycondensation of 4-nitrobenzaldehyde and pyrrole catalysed by Maghnite-H+.
Auteur(s) : Samir. Ghouali Mohammed Seghir. Guellil Mostéfa. Belmokaddem
pp : 329-337
Résumé : Renewable energy shapes have been broadly utilized in the previous decades, featuring a Green move in energy production. A genuine explanation for this swing to Renewable energy generation is internationals directives, which set the worldwide objectives for energy production from inexhaustible sources, greenhouse gas emissions and increase in energy efficiency. The ability expansion-planning problem of the renewable energy industry implies some important decisions concerning the optimal mix of different plant types, locations where each plant should be built, and capacity extension decisions over the planning horizon for each plant.
The aim of this paper is to analyse the relationship between the type of renewable energy by combining the geographical, climatic and ecological criteria, in the Algerian framework, using a multi criteria analysis, precisely Fuzzy Goal Programming model, based on a multi-source, multi-sink network, in order to determine the optimal number of renewable energy plants for electric generation in the Algerian territory.
Auteur(s) : M. Hebali, M. Bennaoum, H.A. Azzeddine, B. Ibari, M. Benzohra, D. Chalabi
ISSN : 2077-6772 | Vol : 12, N° : 06, pp : 1-4
Auteur(s) : H.A.AZZEDDINE , D.CHAOUCH1 , M.Berka1 , M.Hebali A.Larbaoui1 , M.Tioursi
Mots-clés : Fuel cell
Vol : 96, pp : 124-127
Résumé : This article presents a control of a three-phase low voltage grid connected fuel cell system which participating in the improvement of the quality of energy at the connection point by ensuring the reactive energy compensation, the active power control and the harmonic filtering
functionalities. A p-q theory based control has been developed to control the injected fuel cell active power and to allow the system to provide the reactive energy compensation function. The system is structured around a proton exchange membrane (PEM) fuel cell system and a three-phase
voltage inverter.
Auteur(s) : Ali Taghezout, Bendouba Mostefa ,Djebli Abdelkader ,Aid Abdelkarim et Habib Khellafi
Vol : 46, pp : 45-52
Résumé : In this paper a numerical modeling was carried out to study the problem of plane elasticity in a medium cracked by the method of the extended finite elements (XFEM) in a thin cracked plate made of aluminum using the software Abaqus 6.13.This method improved the capability of the classical finite element method especially the crack propagation problems. Furthermore, the extended finite elements method has been used to simulate tensile and fracture behavior of the study materials. Based on variation in size and shape of crack, the results obtained will be compared with those obtained experimentally, this comparison shows a good agreement.
Auteur(s) : Attaouia. Bentahar, Malika. Kandouci, Samir. Ghouali
Résumé : This work is focused to carry out the investigation of wavelength division multiplexing (WDM) approach on free space optical (FSO) transmission systems using Erbium Ytterbium Doped Waveguide Amplifier (EYDWA) integrated as post-or pre-amplifier for extending the reach to 30 Km for the cost-effective implementation of FSO system considering weather conditions. Furthermore, the performance of proposed FSO-wavelength division multiplexing (WDM) system is also evaluated on the effect of varying the FSO range and results are reported in terms of Q factor, BER, and eye diagrams. It has been found that, under clear rain the post-amplification was performed and was able to reach transmission distance over 27 Km, whereas, the FSO distance has been limited at 19.5 Km by using pre-amplification.
Auteur(s) : Amin. Hocine, Mohammed Seghir. Guellil, Eyup. Dogan, Samir. Ghouali, Noureddine. Kouaissah
E-ISSN : 1573-3009 |
Résumé : Optimizing sustainable renewable energy portfolios is one of the most complicated decision making problems in energy policy planning. This process involves meeting the decision maker’s preferences, which can be uncertain, while considering several conflicting criteria, such as environmental, societal, and economic impact. In this paper, rather than using existing techniques, a novel multi-objective decision making (MODM) model, named fuzzy goal programming with interval target (FGP-IT), is proposed and constructed based on recent developments and concepts in fuzzy goal programming (FGP) and revised multi-choice goal programming (RMCGP). The model deals with decision making problems involving a high level of uncertainty by offering decision makers a more flexible way to formulate and express their preferences, namely, fuzzy interval target goals. The proposed method is used to optimize a hypothetical sustainable wind energy portfolio in Algeria. The results show that the FGP-IT model is capable of assisting decision makers with uncertain preferences in making such complicated decisions.
Auteur(s) : Mokhtar Besseghier; Djebbar Ahmed Bouzidi
Mots-clés : Estimation CFO
ISSN : 1757-2665 | E-ISSN : 1757-2657 |
Résumé : Space Time Block Coding-Orthogonal Frequency Division Multiplexing (STBC-OFDM) based MIMO (Multi Input Multi Output) system has been shown to be robust against non ideal operating conditions such as antenna correlation, channel estimation errors, and Doppler effects. But, the later suffers from carrier frequency offset (CFO) which makes channels estimation more challenging.rnIn this paper, we propose joint semi-blind CFO and channels estimators based on modified- multiple signal classification (M-MUSIC) algorithm for STBC-OFDM system over MIMO channels. Channels state information can be estimated at the receiver using pilot symbols embedded in each transmission block. To this end, we propose to encode pilot symbols by a Specific Space-Time Block Coder (S-STBC) while information symbols are encoded by Alamouti based space-time block coding (A-STBC). MUSIC based estimation algorithms are characterized by a high computational complexity. To overcome this drawback, we derive an iterative algorithm which leads to low complexity, high performance CFO and channels estimation. The performance of our algorithms is compared with existing approach by simulations.
Mots-clés : Galerkin method; fractional derivative ; semilinear Equations
Auteur(s) : D. Mohammed
Mots-clés : Fuzzy ; MRI Image Clustering
Vol : 13, N° : 13, pp : 2395-2400
Auteur(s) : K. Fatma Zohra
Mots-clés : Generalized functions; ultradistributions; microlocal analysis
Vol : 46, N° : 2, pp : 181-200
Auteur(s) : B. Chikh
Mots-clés : Colombeau generalized functions; ultradistributions
Vol : 70, N° : 2,
Auteur(s) : B. Chikh
Mots-clés : Colombeau generalized functions; ultradistributions
Vol : 213, pp : 235-250
Auteur(s) : B. Chikh
Mots-clés : Colombeau generalized functions; ultradistributions
Vol : 41, pp : 53-62
Auteur(s) : B. Chikh
Mots-clés : Colombeau generalized functions; Regularity
Vol : 88, pp : 39-53
Auteur(s) : B. Chikh
Mots-clés : Colombeau generalized functions; Regularity
Vol : 15, N° : 3, pp : 37-72
Auteur(s) : B. Chikh
Mots-clés : Colombeau generalized functions; Regularity
Vol : 15, N° : 4, pp : 427—447
Auteur(s) : B. Chikh
Mots-clés : Colombeau generalized functions; solvability of differential operators
Vol : 25, N° : 4, pp : 467-477
Auteur(s) : houraya Bouabana-Tebibel ; Stuart H. Rubin ; Kadaouia Habib ; Sofia Mellah ; Lynda Allata
Mots-clés : Complex Systems , Component-Based Language , Domain-Specific Language , SysML
N° : 13867497,
Résumé : Abstract:
The modeling and design of complex systems continues to face grand challenges in feedback and control. Existing languages and tools, either textual or graphical, bring some improvement for such purposes, but much remains to be done in order to readily insure scalability. In this paper, we propose a language, which gathers specialization and composition properties. It is our belief that the latter properties bear the necessary capabilities to overcome the difficulties raised when developing these systems. The language is designed, on one hand, in a way to be specific to complex system domains. It supports, on the other hand, a component-based structure that conforms to a user-friendly component assembly. It is conceived in the spirit of SysML concepts. Its' programs generate Internal Block Diagrams. A programming tool is built on the basis of the Eclipse framework.
Auteur(s) : S. Bentata , B. Ait Saadi & H. Sediki
Auteur(s) : Z. Aziz, S. Bentata and R. Djelti
Auteur(s) : Z. Aziz, S. Bentata and R. Djelti
Auteur(s) : R. Djelti, S. Bentata and Z. Aziz
Auteur(s) : R. Djelti, S. Bentata and Z. Aziz
Auteur(s) : H. Khalfoun, M. Bouamoud and S. Bentata
Auteur(s) : R. Bentata and S. Bentata
Auteur(s) : R.Djelti, S. Bentata and Z. Aziz
Vol : 8, N° : 1,
Auteur(s) : H. Khalfoun, S. Bentata, M. Bouamoud and L. Henrard
Auteur(s) : R.Djelti, S. Bentata, Z. Aziz and A. Bebes
Auteur(s) : Z. Aziz, S. Bentata, R. Djelti and E. Alandaloussi
Vol : Vol. 23, N° : No. 19,
Auteur(s) : R.Djelti, S. Bentata, Z. Aziz and A.. Besbes
Vol : , Vol. 23, N° : No. 25 5067 ,
Auteur(s) : H Khalfoun, M Bouamoud, S Bentata, L Henrard and C Vandenbem
Vol : , Vol. 23, N° : No. 25 5067 ,
Auteur(s) : R.Djelti, S. Bentata, Z. Aziz and A.. Besbes
Vol : 23, N° : 25 5067 ,
Auteur(s) : R.Djelti, S. Bentata, Z. Aziz and A.. Besbes
Auteur(s) : H. Khalfoun, S. Bentata, M. Bouamoud, L. Henrard and C. Vandenbem
Auteur(s) : Z. Aziz, S. Bentata, R. Djelti and Y. Sefir
Auteur(s) : Z. Aziz, Y. Sefir, R. Djelti and S. Bentata
Auteur(s) : R.Djelti, Aziz.Z, Bentata.S, A Besbes
Auteur(s) : S.Terkhi, S.Bentata, R.Djelti, B.Bouadjemi
Auteur(s) : A. Abbad, S. Bentata, W. Benstaali, H.A. Bentounes, and B.Bouadjemi
Auteur(s) : A. Abbad, W. Benstaali, H.A. Bentounes, S. Bentata and A. Belaidi
Auteur(s) : W. Benstaali, S. Bentata, A. Abbad and A. Belaidi
Auteur(s) : S.Terkhi, Z. Aziz, S.Bentata, B.Bouadjemi
Auteur(s) : F.Z. Meghoufel, S. Bentata, S. Terkhi, F. Bendahma and S. Cherid
Auteur(s) : B. Bouadjemi, S. Bentata, A. Abbad, W. Benstaali and B.Bouhafs
Auteur(s) : R.Djelti, Z. Aziz, S. Bentata
Auteur(s) : W. Benstaali, S. Bentata, H. A. Bentounes, A. Abbad, B. Bouadjemi
Auteur(s) : S. Cherid, S. Bentata, R.Djelti and Z. Aziz
Auteur(s) : A. Zitouni, S. Bentata, W. Benstaali and B.Abbar
Auteur(s) : B. Bouadjemi, S. Bentata, A. Abbad and W. Benstaali
Auteur(s) : A. Abbad, H. A. Bentounes, W. Benstaali, S. Bentata, B. Bouadjemi
Auteur(s) : Radouan Djelti, Samir Bentata, Zoubir Aziz and Anissa Besbes
Auteur(s) : A. Abbad, H. A. Bentounes, W. Benstaali, S. Bentata, B. Bouadjemi
Auteur(s) : A. Abbad, W. Benstaali, H. A. Bentounes, S. Bentata, Y. Benmalem
Auteur(s) : A. Souidi, S. Bentata, W. Benstaali, B. Bouadjemi, A. Abbad, T. Lantri
Auteur(s) : F. Bendahma, R. Djelti and S. Bentata
Auteur(s) : T. Lantri, S. Bentata, B. Bouadjemi, W. Benstaali, B. Bouhafs, A. Abbad, A. Zitouni
Auteur(s) : S. Cherid W. Benstaali, A. Abbad, S. Bentata, T. Lantri, B. Abbar,
Auteur(s) : M. Rezaiguia, W. Benstaali, A. Abbad, S. Bentata, B. Bouhafs
Auteur(s) : Bouziane M M, Khaldi M, Serier B, Benseddiq N, Zerdali M, Benbarek S, Bachir Bouiadjra B A
Auteur(s) : H.A.Azzeddine, M.Tioursi. D.chaouch
Mots-clés : PV, modélisation, RBF
ISSN : 1841-3323 | Vol : 54, N° : 6, pp : 1-3
Auteur(s) : Zouzou, Noureddine & Mayer-Laigle, Claire & Rouau, Xavier & Zouaghi, Ayyoub & Fouad, Kherbouche & Dascalescu,L
Mots-clés : Corona discharge; Electrostatic hazards; Electrostatic precipitators; Finely ground lignocellulosic materials; Particle collection efficiency; Triode-type electrodes.
ISSN : 0093-9994 | E-ISSN : 1939-9367 | Vol : 55, N° : 3, pp : 3114 - 3121
Résumé : The main objective of this paper is to develop a novel two-stage-type electrostatic precipitator to collect finely ground lignocellulosic particles. To prevent the danger of explosion of such a powdery material, ion generation and particle charging processes are separated. Main results show that the particles can be highly charged in a two-coaxial-cylinders triode-type device, which also facilitates their collection. For instance, the collection efficiency reaches 92 % for particle size of about 0.3 μm, and exceeds 99% for particle size greater than 2 μm.
Auteur(s) : I. ALIMIICHOLA, L. GAIDI
Mots-clés : leachate, unsaturated soil, TDR methed
Vol : 85, N° : 1-2, pp : 2-8
Résumé : To design waste containment barriers, low permeability soils or manufactured liner products are required. For hydraulic barriers in waste containment system, it is recommended to use soil layer of 5 m thickness when the coefficient of the permeability is higher than 10− 6 m/s or a layer of one meter thickness, when the coefficient of permeability is lower than 10− 9 m/s. So some authors tried to prove analytically, that the barrier thickness can be reduced when the permeability of the soil is less than 10− 9 m/s (e.g. 10− 10 or 10− 11 m/s). This suggestion does not take into account the ion sorption and the solute migration delay which can occur in an unsaturated zone and reduce the solute transfer
Mots-clés : المعنى، الدّلالة، اللسانيات، السياق، النظرية السياقية، التداولية
ISSN : 2520-7148 | E-ISSN : 2520-713X | Vol : 02, N° : 01, pp : 83-96
Résumé : يعتبر المعنى من القضايا الأكثر أهمية في الكلام البشري، فهو الهدف المقصود من أيّ نظام لغويّ، أمّا المستويات اللسانية الأخرى (الصوتية والصرفية والتركيبية) فهي حاملة للمعنى، ووسيلة أساسية من وسائل التبليغ. ونظراً لطبيعة المعنى التي تمتاز بالغموض والتغيّر والتبدّل، كانت الحاجة ماسّة لدراسة هذا المكوّن المهمّ من مكوّنات اللسان البشريّ، فظهر بسبب ذلك علم الدّلالة، الذي ناقش قضايا المعنى بشبكة من الآليات المعرفية التي سمحت بالحفر في المعنى والوصول إلى نتائج أكثر دقّة وموضوعية
Mots-clés : البشير الإبراهيمي، الحجاج، التداولية، اللسانيات، الدلالة
ISSN : 2335-1071 | E-ISSN : 2602-5922 | Vol : 02, N° : 05, pp : 73-91
Résumé : يمثّل الحجاج الركن الأساس لفن الخطابة، بسبب حاجة هذه الأخيرة لمختلف الأدوات التي تمكّنها من التأثير في المتلقي وتغيير قناعاته، وهو ما نلمس أثره بوضوح في خطبة الشيخ الإبراهيمي التي ألقاها في مسجد كتشاوة، حيث استخدم ترسانة من الآليات الحجاجية، معتمدا على ذخيرة لغوية وثقافية هائلة، سمحت بتنويع المنظومة الحجاجية عبر ثلاثة أسس؛ الأساس الاستشهادي، والأساس الأسلوبي، والأساس المنطقي. وقد تفرّع كلّ واحد منها إلى بنيات حجاجية أصغر، سمحت في النهاية ببناء شبكة حجاجية قوية، ومترابطة، ومنسجمة، تجمع بين الإقناع والإمتاع.
Mots-clés : سيميائية ، الفضاء المقدّس، الرحلات الحجازية، الجزائرية، الحسين الورثيلاني
ISSN : 2478-0197 | E-ISSN : 2676-1718 | Vol : 03, N° : 01, pp : 09-25
Résumé : يعتبر أدب الرّحلة مجالاً فنياً ومعرفياً مهمًّا في تاريخ الثقافة العربية، فهو يتقاطع مع التاريخ والجغرافيا والدين والأدب والفلسفة.. ما يجعله يحظى بالكثير من الخصوصية، وقابلاً للتناول المعرفي ضمن مسارات بحثية مختلفة، ونظراً لمركزية الفضاء في فعل الارتحال، فإنّ هذه الورقة حاولت أن تبحث في رمزيته ضمن معطيات المنهج السّيميائي، طمعاً في الوصول إلى الدّلالات الثاوية خلف هذه العلامة.
Auteur(s) : S.nawel, B.Aicha
Mots-clés : Pratiques théâtrales, théâtre, communication orale, compétence orale, enseignement/apprentissage du français.
ISSN : 1112-4245 1112-4245 1112-4245 | N° : 10-11, pp : p. 331 - 344
Résumé : Cet article porte sur les pratiques théâtrales en classe de FLE. Il propose une réflexion sur la manière d’utiliser le théâtre comme outil pédagogique pour apprendre le FLE. IL s’agit d’une expérience menée avec mes étudiants de 1ère année LMD, du département de langue et littérature françaises de l’université de Mascara (Algérie). Nous voulons revenir ici sur une pratique différente,qui n’a pas été suffisamment exploitée par les enseignants et pratiquée par les étudiants en classe. Visant donc à leur faire prendre conscience de la réalité de la langue française telle qu’elle se parle, et développer chez eux l’expression orale, et encourager les enseignants à intégrer les activités théâtrales en classe sans objectif de monter une pièce théâtrale, mais de travailler l’oral de manière ludique.
Auteur(s) : Meriem Amina Zingla, Chiraz Latiri, Yahya Slimani, Catherine Berrut
Mots-clés : Tweet contextualization track Twitter Query expansion Wikipedia Association rules Informativeness evaluation.
Vol : 60, N° : 1, pp : 498-507
Auteur(s) : Meriem Amina Zingla, Chiraz Latiri, Yahya Slimani
Mots-clés : Short query expansion Microblog retrieval Wikipedia DBpedia TREC microblog
Vol : 96, N° : 1, pp : 225-234
Auteur(s) : Khellafi Habib , Bendouba Mostefa ,Djebli Abdelkader, Aid Abdelkrim, Benseddiq Noureddine , Benguediab Mohamed , Talh Abderrahim.
Vol : 5 (2018), pp : 73–80
Résumé : Mechanical and structural components are subject in the most cases during their services to random loading. For this reason, it is necessary to reduce the complex history of these kinds of loading in a series of constant amplitude cycles. There are several counting methods that lead to different results. Among all these methods, it is recognized that the Rainflow Cycle Counting method provides the most conservative results. In this paper, a finite elements analysis technique is presented to predict the fatigue life using this method associate with the S-N method which is used for high cycle fatigue applications that makes no distinction between initiation or growing a crack, but rather, predicts the total life to failure. Comparison between numerical and experimental results is considering in this paper.
Mots-clés : الدين، الفلسفة، التطور، المنهج، فلسفة الدين
ISSN : 2253-0592 | Vol : 11, N° : 08/01, pp : 155-166
Résumé : نحاول في موضوعنا طرح تحليل فلسفي لتطور العلاقة بين مجالين مهمين من حياة البشر، ألا وهما الدين والفلسفة، حيث نطمح إلى فهم التغير الحاصل في النظر إلى مفهوم وموضوع وغاية الدين عبر تاريخ الفكر الفلسفي، لفهم طبيعة الوثبة الحاصلة من فلسفات دينية إلى فلسفة في الدين وإشكال مقالنا ينطلق من وجود نقلة نوعية عرفها الفكر الفلسفي حول الدين من فلسفات دينية مجالها التسليم أو الاعتقاد ثم التعقل إلى فلسفة في الدين تتأسس على الانتقاد و التعقل دون حدود وقيود مواكبة مستجدات الواقع والعلم
Auteur(s) : KHELLAFI Habib,Bouziane Mohamed Mokhtar ,Djebli Abdelkader, Abdeldjelil Mankour,Bendouba Mostefa,Bel Abbes Bachir Bouiadjra et Ould Chikh El Bahri.
Vol : 41,
Résumé :
Generally, implants fixations in orthopedic surgery are insured by bone cement; which is generated mainly from polymer polymethylmethacrylate (PMMA). Since, the cement is identified as the weakest part among bone-cement-prosthesis assembly. Hence, the characterization of mechanical behaviour is of a crucial requirement for orthopaedic surgeon’s success. In this study, we investigates the failure behaviour of bone cement, under combined shear and compression loading, for the aim to determine the strengths of bone cement for different mode loading conditions. Therefore, experimental cylindrical specimens has been tested to assess different shear-compression stresses. Based on the mechanical tests, a finite elements model of cylindrical specimens was developed to evaluate stresses distribution in the bone cement under compression, shear and combined shear-compression loading. Results show that, the load which leading to the failure of the cement decreased with increasing of the specimen angle inclination with respect of loading direction.
Auteur(s) : KHELLAFI Habib , Meddah Hadj miloud, OuldChikh El Bahri,Bouchouicha Benattou, Benguediab Mohamed et Bendouba Mostefa
Vol : 49, N° : 1,
Résumé : The polyvinyl chloride PVC is a polymer material widely used for a large variety of applications. The present work focuses on the identification of the physical processes responsible for the mechanical properties of the PVC containing different crystallinities rate applied in large deformation and different strain rates. In order to understand the behavior of the PVC, a thermodynamic modeling is needed. Therefore, the contribution of this approach was demonstrated by experiment and numerical modeling. This comparative study demonstrates that the proposed model provides better agreement with experimental evidence.
Auteur(s) : Ali Boudjelal Moulay., Bouiadjera Bachir Belabbes., Ould Chikh El Bahri, Elmeguenni Mohamed,
Mots-clés : Amorphous Polymer, Damage, Mechanical Behavior, Modeling
ISSN : 2369-0739 | E-ISSN : 2369-0747 | Vol : 4, N° : 1, pp : 53-58
Résumé : In manufacturing operations, numerous parts and components are formed into different shapes by applying external forces to the workpiece, typically by means of various tools and dies. Common examples of such operations are forging, extruding, drawing and rolling. Forming operations may be carried out at room temperature or at elevated temperatures, and at a low or a high rate of deformation. These operations are also used in forming and shaping non-metallic materials such as plastics and ceramics. However, the processes of working of polymers in a solid state are affected by phenomena of plastic instabilities. These phenomena are interpreters on the basis of intrinsic law of behavior of the material which express the influence of the deformation and the rate of deformation on the plastic yield stress. This law directly reflects the structural modifications undergone by material under the conditions of the test. In addition, she gives the necessary information to the modeling of instabilities using techniques of calculation such as the finite element method.
Auteur(s) : S. Habibi, L. Aminallah, A. Megueni, B. OuldChikh, A. S. Bouchikhi
Mots-clés : small punch test ; plan d’expériences ; optimisation ; dimensionnement ; contraintes
Vol : 1 , N° : 1, pp : 8-15
Résumé : La technique small punch test (SPT) d’un échantillon en miniature est mise en oeuvre pour estimer la charge ultime de l'acier ductile CrMoV. Les courbes caractéristiques par SPT (F-d) pour différentes combinaisons des variables d’essai (épaisseur du spécimen, diamètre du punch et matrice inférieure) ont été examinées. L’objet de cette étude est la mise en oeuvre d'une méthodologie d’optimisation susceptible d’évaluer et de concevoir le dimensionnement du dispositif d’indentation qui répond à la fois aux exigences des modèles implémentés et au modèle proposé par le plan d’expériences. On a adopté une démarche fondée sur l’approche comparative entre les plans d’expériences et les deux méthodes (code de pratique européenne et méthode de Norris et Parker). Le modèle mathématique élaboré par plan d’expériences est implémenté sous Matlab, permet à partir d’un espace de recherche considéré (données de références), une optimisation des paramètres du dispositif, en minimisant l’écart entre les modèles étudiés, sous contraintes pratiques liées au système d’indentation ‘’Pièce-Outil-Machine’’. Les résultats obtenus à une erreur de 0.5*e-3 permettent de déterminer le domaine admissible.