20 research outputs found

    Conductivity modeling of gas sensors based on copper phthalocyanine thin films

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    The main objective of this work is to study the electronic conductivity of copper phthalocyanine (CuPc) thin films in presence of certain strong oxidizing gases involved in air pollution, particularly NO2, for use as gas sensor devices. To achieve this objective, the first part presents a study of the conductivity evolution of these sensors, in order to find the optimal operating temperature and to improve the kinetics of adsorption of gas molecules on the surface of the thin layer. In a second step, we tried to develop a mathematical model that describes as closely as possible the electrical behavior of these sensors in order to simulate their operation and optimize their performances. Elovich models have been applied to both gas adsorption and desorption phases and have led to good similarities between theoretical and measured response curves.Keywords: Gas sensors - thin layer - phthalocyanine - conductivity - modelin

    Complexity analysis of primal-dual algorithms for the semidefinite linear complementarity problem

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    In this paper a primal-dual path-following interior-point algorithm for the monotone semidefinite linear complementarity problem is presented. The algorithm is based on Nesterov-Todd search directions and on a suitable proximity for tracing approximately the central-path. We provide an unified analysis for both long and small-update primal-dual algorithms. Finally, the iteration bounds for these algorithms are obtained

    Ù†ŰžŰ±Ű© في كŰȘۧۚ (Ű§Ù„Ű„ŰłÙ„Ű§Ù… ÙˆŰŁŰ”ÙˆÙ„ Ű§Ù„Ű­ÙƒÙ…) Ù„Ù„ŰŽÙŠŰź Űčلي ŰčŰšŰŻŰ§Ù„Ű±Ű§ŰČق

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    Les rapports entre le politique et le religieux occupent une place trĂšs importante dans le domaine de la recherche. Pour les pays occidentaux la sphĂšre politique et religieuse est bien distincte. En terre d’islam, le couple religion-islam va couvrir l’espace de vie dans sa totalitĂ©, l’Islam est source du politique, c'est-Ă -dire la vie d’ici bas et du spirituel, une confusion qui fait que les musulmans jusqu'Ă  nos jours n’ont toujours par rĂ©solu l’équation sphĂšre politique et sphĂšre religieuse. Tout au long de l’histoire islamique les califats jaloux de leurs prĂ©rogatives, vont tout faire pour affirmer leur lĂ©gitimitĂ© et leur domination, une pratique qui va crĂ©er dans l’imaginaire musulman un repĂšre sur l’art de la gouvernance, plus tard un exemple Ă  suivre. En 1925 un ‘Alim va marquer une rupture avec la confusion du politique et de la religion, proposant une sĂ©paration entre les deux et la recherche d’une nouvelle science politique, celle qui se base sur la raison. Notre travail de recherche a comme point de dĂ©part l’ouvrage polĂ©mique d’Ali Abderraziq, L’islam et les fondements du pouvoir, nous avons voulu remettre au goĂ»t du jour les thĂšses avancĂ©es dans cet ouvrage que Abdou FILALI-ANSARY qualifie de traitĂ© dĂ©cisif sur une question majeure et dĂ©licate, celle des rapports entre le pouvoir politique et le pouvoir religieux. Nous nous sommes intĂ©ressĂ©s dans ce travail aux rapports entre les deux pouvoirs dans les moments fondateurs de la pensĂ©e islamique, Ă  savoir la pĂ©riode prophĂ©tique, celle des califes et le monde d’aujourd’hui. La pĂ©riode de naissance de la umma fut celle de propagation du message divin mais aussi crĂ©ation d’une communautĂ©, qui va vite, par un acte naturel chercher Ă  s’unir autour d’un chef une fois que Mohamed n’est plus de ce monde. De ce fait La question de la succession va rythmer la vie politique dans le monde musulman, et souvent c’est dans le sang que les conflits vont ĂȘtre rĂ©solus. Nous avons tentĂ© d’approcher les liens entre les deux pouvoirs. Pour finir nous nous sommes intĂ©ressĂ© au retour du discours islamique.The relationship between politics and religion is a particularly important part of research. For Western countries, the political and religious sphere is quite distinct. In the land of Islam, the religion-Islam couple will cover the entire living space, Islam is the source of politics, that is, the life of here and the spiritual, a confusion that makes Muslims to this day have not yet solved the equation of the political sphere and the religious sphere. Throughout Islamic history, the caliphate jealous of their prerogatives, will do everything to assert their legitimacy and domination, a practice that will create in the Muslim imagination a reference on the art of governance, later an example to follow. In 1925 an 'Alim will mark a break with the confusion of politics and religion, proposing a separation between the two and the search for a new political science, one based on reason. Our research work starts with Ali Abderraziq polemical work, “Islam and the foundations of power”, and we wanted to update the theses put forward in this book, which Abdou FILALI-ANSARY describes as a decisive treatise on a major and delicate issue, that of the relationship between political and religious power. We have been interested in this work in the relationship between the two powers in the founding moments of Islamic thought, namely the prophetic period, that of the caliphs and the world of today. The period of birth of the umma was that of the propagation of the divine message but also the creation of a community, which goes quickly, by a natural act seek to unite around a leader once Mohamed is no longer of this world. As a result, the question of succession will punctuate political life in the Muslim world, and often it is in the blood that conflicts will be resolved. We have tried to approach the links between the two powers. Finally, we were interested in the return of Islamic discourse

    Les rapports entre pouvoir sĂ©culier et pouvoir religieux dans le monde arabe et musulman : Une Ɠuvre de rupture : Le traitĂ© dĂ©cisif d’Ali ABDERRAZIQ intitulĂ© « L’islam et les fondements du pouvoir  »

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    The relationship between politics and religion is a particularly important part of research. For Western countries, the political and religious sphere is quite distinct. In the land of Islam, the religion-Islam couple will cover the entire living space, Islam is the source of politics, that is, the life of here and the spiritual, a confusion that makes Muslims to this day have not yet solved the equation of the political sphere and the religious sphere. Throughout Islamic history, the caliphate jealous of their prerogatives, will do everything to assert their legitimacy and domination, a practice that will create in the Muslim imagination a reference on the art of governance, later an example to follow. In 1925 an 'Alim will mark a break with the confusion of politics and religion, proposing a separation between the two and the search for a new political science, one based on reason. Our research work starts with Ali Abderraziq polemical work, “Islam and the foundations of power”, and we wanted to update the theses put forward in this book, which Abdou FILALI-ANSARY describes as a decisive treatise on a major and delicate issue, that of the relationship between political and religious power. We have been interested in this work in the relationship between the two powers in the founding moments of Islamic thought, namely the prophetic period, that of the caliphs and the world of today. The period of birth of the umma was that of the propagation of the divine message but also the creation of a community, which goes quickly, by a natural act seek to unite around a leader once Mohamed is no longer of this world. As a result, the question of succession will punctuate political life in the Muslim world, and often it is in the blood that conflicts will be resolved. We have tried to approach the links between the two powers. Finally, we were interested in the return of Islamic discourse.Les rapports entre le politique et le religieux occupent une place trĂšs importante dans le domaine de la recherche. Pour les pays occidentaux la sphĂšre politique et religieuse est bien distincte. En terre d’islam, le couple religion-islam va couvrir l’espace de vie dans sa totalitĂ©, l’Islam est source du politique, c'est-Ă -dire la vie d’ici bas et du spirituel, une confusion qui fait que les musulmans jusqu'Ă  nos jours n’ont toujours par rĂ©solu l’équation sphĂšre politique et sphĂšre religieuse. Tout au long de l’histoire islamique les califats jaloux de leurs prĂ©rogatives, vont tout faire pour affirmer leur lĂ©gitimitĂ© et leur domination, une pratique qui va crĂ©er dans l’imaginaire musulman un repĂšre sur l’art de la gouvernance, plus tard un exemple Ă  suivre. En 1925 un ‘Alim va marquer une rupture avec la confusion du politique et de la religion, proposant une sĂ©paration entre les deux et la recherche d’une nouvelle science politique, celle qui se base sur la raison. Notre travail de recherche a comme point de dĂ©part l’ouvrage polĂ©mique d’Ali Abderraziq, L’islam et les fondements du pouvoir, nous avons voulu remettre au goĂ»t du jour les thĂšses avancĂ©es dans cet ouvrage que Abdou FILALI-ANSARY qualifie de traitĂ© dĂ©cisif sur une question majeure et dĂ©licate, celle des rapports entre le pouvoir politique et le pouvoir religieux. Nous nous sommes intĂ©ressĂ©s dans ce travail aux rapports entre les deux pouvoirs dans les moments fondateurs de la pensĂ©e islamique, Ă  savoir la pĂ©riode prophĂ©tique, celle des califes et le monde d’aujourd’hui. La pĂ©riode de naissance de la umma fut celle de propagation du message divin mais aussi crĂ©ation d’une communautĂ©, qui va vite, par un acte naturel chercher Ă  s’unir autour d’un chef une fois que Mohamed n’est plus de ce monde. De ce fait La question de la succession va rythmer la vie politique dans le monde musulman, et souvent c’est dans le sang que les conflits vont ĂȘtre rĂ©solus. Nous avons tentĂ© d’approcher les liens entre les deux pouvoirs. Pour finir nous nous sommes intĂ©ressĂ© au retour du discours islamique

    Performance Evaluation of IPFC with SMES on the Power System Stability

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    Voltage Source Converter (VSC)-based Flexible Alternative Current Transmission Systems (FACTS) controllers are capable of providing reactive power support and control active and reactive power flow, which will result in improving the power transfer capability of congested transmission lines. The Interline Power Flow Controller (IPFC) and the Superconducting Magnetic Energy Storage (SMES) are the FACTS devices. This paper proposes the use of the IPFC in combination with the SMES as an effective device to enhance the stability of the Single Machine Infinite Bus (SMIB) power system taken as test system. SMES is connected to the dc side of IPFC through an interface with DC-DC chopper. The performance of the IPFC can be improved with the addition of energy storage. A detailed model of IPFC-SMES controller is proposed and a new control scheme is designed. The dynamic performance of the proposed device is validated through digital simulation carried out by using SimPowerSystems of Matlab/Simulink. The results of the simulation show that the used approach can significantly enhance the power system stability

    Le problÚme de complémentarité linéaire semi-défini

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    Dans cet article on présente une synthÚse sur les principaux travaux liés au problÚme de complémentarité linéaire semi-défini. La présentation est donnée de façon à rendre le bagage utilisé pour ce problÚme comprehensible et permettant de nouveaux développements

    Relation microstructure - comportement macroscopique dans les aciers (effet de la taille de grain austénitique sur la plasticité de transformation)

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    Ce travail est une contribution Ă  l'Ă©tude des consĂ©quences mĂ©caniques des transformations de phase Ă  l'Ă©tat solide dans les aciers, en particulier la plasticitĂ© de transformation (TRIP), en prenant en compte l'effet de la taille de grain austĂ©nitique (AGS). L'Ă©volution de l'AGS a Ă©tĂ© Ă©tudiĂ©e sous diffĂ©rentes conditions d'austĂ©nitisation. Des essais de plasticitĂ© de transformation ont Ă©tĂ© conduits avec les mĂȘmes conditions d'austĂ©nitisation afin d'observer l'Ă©volution du TRIP avec l'AGS. Trois types de chargement mĂ©canique sont considĂ©rĂ©s : la traction uniaxiale, la torsion uniaxiale et le cas biaxial de traction + torsion. Les rĂ©sultats montrent que : i) le TRIP augmente avec l'AGS dans le cas de la traction ; ii) il est indĂ©pendant de l'AGS pour la torsion; iii) pour le cas du changement biaxial, le TRIP diminue lĂ©gĂšrement. Ceci montre que les modĂšles dĂ©crivant le TRIP doivent ĂȘtre revus afin de prendre en compte l'AGS.This work is a contribution to the study of mechanical consequences of solid-solid state phase transformations in steels, particularly the Transformation Induced Plasticity (TRIP), and the effect of the Austenite Grain Size (AGS). The evolution of AGS was studied taking into account different austenitization conditions. Then, TRIP tests were carried out with the same conditions to observe the evolution of TRIP with AGS. Three types of loading are considered: the uniaxial tension case, torsion case and biaxial tension and torsion case. The resuslts show that: i)the TRIP increase with AGS in the tensile case. ii) It is independant for the torsion case. iii) For the biaxial loading case, the TRIP decreases slightly. This shows that the micromechanical models describing the TRIP should be reviewed to take account of the AGS.ROUEN-INSA Madrillet (765752301) / SudocSudocFranceF

    OĂč va l'AlgĂ©rie ?. 1, Notre rĂ©volution / Mohamed Boudiaf...

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