36 research outputs found
Partir, revenir, ĂȘtre du M'Zab et d'ailleurs. Regard interdisciplinaire autour des modalitĂ©s de la circulation migratoire
International audienceThis article will explore, by a multidisciplinary way, the concept of circular migration under a dual approach, epistemological and empirical , and illustrate this concept by studying the Mozabite diaspora, a linguistic and religious minority of Algerian, immigrant outside its territory of origin. First, are articulated the different theoretical concepts involved in the migratory movement (migration chain, network migration, migration field, etc) which will, in a second time, applied to the community Mozabite immigrant in Marseille (France). Finally, a communicational approach is mobilized to show how the digital practices and the social web facilitate communication between the various components of this community, cultural transmission and preservation of social ties between people remained in M'Zab and those who are remote.Cet article se propose d'explorer de maniÚre pluridisciplinaire la notion de circulation migratoire sous une double approche, épistémologique et empirique, à partir du regard croisé des sciences de l'information et de la communication et de la géographie, et d'illustrer ce concept par l'étude de la diaspora mozabite, une minorité religieuse et linguistique algérienne, immigrée en dehors de son territoire d'origine. Dans un premier temps, sont donc approfondis et articulés les différents concepts théoriques participant à la circulation migratoire (filiÚre migratoire, réseau migratoire, champ migratoire, etc) qui seront, dans un second temps, appliqués à la communauté mozabite immigrée à Marseille. Enfin, une approche communicationnelle est mobilisée pour montrer comment les pratiques numériques, le web social facilitent la communication entre les différentes composantes de cette communauté, la transmission culturelle et la préservation des liens sociaux entre les populations restées au M'Zab et celles qui en sont éloignées
Comparative Study of Temperature Effect on Thin Film Solar Cells
The quaternary compound Cu2ZnSnS4 (CZTS) is considered as an alternative material to replace CIGS
material in future manufacturing of thin film solar cells. In this paper, a comparative study of temperature
effect on thin film CZTS (Cu2ZnSnS4) and CIGS (Cu(In, Ga)Se2) solar cells was leaded. For this purpose we
used the one dimensional simulation program tool SCAPS-1D (Solar Cell Capacitance Simulator in one
Dimension. The dependence of the CZTS and CIGS solar cells characteristics with temperature was investigated
from 300°K to 360°K. The comparative results showed that the cell with CZTS had an improved
behavior at high operation temperatures. The maximum power coefficients, depending on temperature variations,
were respectively â 1.8 mW/cm2 °K and â 7.84 mW/cm2 °K
Boosting CZTSSe Solar Cell Efficiency by Back Surface Field Layer
In this work, a simulation of the CZTSSe (Cu2ZnSn(S,Se)4) solar cell with Al/ZnO:Al/ZnO(i)/CdS/ CZTSSe/Mo structure have been studied using the SCAPS-1D (Solar Cell Capacitance Simulator in one Dimension). The simulation results have been validated with real experimental results. Next, a novel structure is proposed in which a back surface field (BSF) layer is inserted in order to boost the solar cell performance, a CZTSSe layer has been used as (BSF) layer. The efficiency of CZTSSe solar cell increases from 12.3 % to 15.3 % by inserting a BSF layer. Finally, an optimization of different physical parameters (Thickness and doping concentration) of BSF layer has been done, and the optimum values are determined. In this research work, the proposed structure of CZTSSe solar cells with optimum parameters showed higher functional properties, The maximum value of efficiency achieved was 16.98 % with Jsc = 36.31 mA/cm2, Voc = 0.69 V, and FF = 69.60% under 1.5G AM illumination
Migrations, territorialities, intercultural dynamics : The example of the Algerian Mozabites minority
Ă lâheure oĂč la mobilitĂ© est accrue et les valeurs culturelles se dirigent de plus en plus vers lâunification, il nous a paru important dâobserver les migrations des groupes diasporiques Ă fortes valeurs identitaires et dâanalyser leurs territorialitĂ©s et leurs dynamiques interculturelles. Ce travail ambitionne donc dâamorcer une Ă©tude gĂ©ographique du phĂ©nomĂšne migratoire diasporique. Il porte le regard sur lâanalyse de lâespace migratoire qui se forme entre le lieu dâorigine du groupe minoritaire et ses pĂŽles dâinstallation avec un exemple prĂ©cis sur la minoritĂ© ethnolinguistique et religieuse des Mozabites algĂ©riens qui migrent et sâapproprient diffĂ©rents pĂŽles dans le contexte interne et international. Le choix dâanalyser plusieurs pĂŽles dâinstallation (El-Eulma en AlgĂ©rie, Marseille et Lille en France) et de mettre en rapport la migration interne et la migration internationale de ce groupe, a permis dâĂ©valuer lâinfluence des diffĂ©rents facteurs sur la conception des phĂ©nomĂšnes migratoires diasporiques. Il a aussi Ă©clairĂ© sur la maniĂšre dont lâappartenance identitaire est une variable que le groupe diasporique sollicite fortement pour former son espace et son systĂšme migratoireAt a time when mobility is increasing and cultural values are moving more and more towards unification, it was important to observe the migration of diasporic groups with strong identity values and to analyze their territorialities and intercultural dynamics. This work aims to initiate a geographical study of the diasporic migratory phenomenon. It is concerned with the analysis of the migratory space between the original place of the minority group and its poles of settlement with the specific example of the ethnolinguistic and religious minority of the Algerian Mozabites who migrate and appropriate different clusters in the internal and international context. The choice of analyzing several installation clusters (El-Eulma in Algeria, Marseille and Lille in France) and to compare the internal migration with the international migration of this group, made it possible to evaluate the influence of the different factors on the design of diasporic migratory phenomena. It also enlightened on how identity belonging is a variable solicited by the diasporic group to form its space and its migratory syste
Culture et pratique de lâespace urbain. Analyse de la production et de lâappropriation spatiale Ă partir des exemples comparĂ©s des communautĂ©s mozabites de GhardaĂŻa et SĂ©tif
International audienc
IdentitĂ©s culturelles sexuĂ©es et pratiques de lâespace public: exemple de la diaspora Mozabite immigrĂ©e Ă El Eulma (AlgĂ©rie)
International audienc
La pratique genrĂ©e de lâespace public Ă lâĂ©preuve dâune lĂ©gitimitĂ© culturelle : le cas de la minoritĂ© Mozabite immigrĂ©e dans le nord algĂ©rien
International audienceCette communication sâintĂ©resse Ă lâimpact des facteurs culturels (tant sous lâangle de lâidentitĂ© sociale/collective quâindividuelle) dans la production spatiale Ă travers lâĂ©tude de lâappropriation et du mode dâhabiter du systĂšme urbain dâune minoritĂ© religieuse d'AlgĂ©rie, les Mozabites, immigrĂ©e dans la ville d'El-Eulma (wilaya de SĂ©tif). L'Ă©tude des pratiques spatiales dans un contexte dâinterculturalitĂ© a mobilisĂ© plusieurs approches mĂ©thodologiques : enquĂȘtes par questionnaires, entretiens semi-directifs, observation participante. LâintĂ©rĂȘt sâest notamment portĂ© sur la variabilitĂ© des pratiques selon lâĂąge et surtout le genre. Au final cette recherche nous Ă©claire sur lâusage de l'espace public, les trajectoires gĂ©ographiques quotidiennes des individus, ainsi que sur les modes dâappropriation de la population mozabite dans un contexte dâinterculturalitĂ©
Réseau migratoire et intégration des nouveaux migrants : exemple des communautés mozabites d'El Eulma (Algérie) et de Marseille ( France)
International audienceCet article sâintĂ©resse aux conditions dâaccueil des migrants et Ă leurs modĂšles dâintĂ©gration dans leurs nouveaux territoires dâinstallation Ă partir de lâanalyse des rĂ©seaux migratoires, des initiatives conduites par les acteurs en dehors de tout cadre institutionnel. Pour Ă©tudier le phĂ©nomĂšne, notre attention sâest portĂ©e sur une communautĂ© ethno-linguistique et religieuse particuliĂšre, les Mozabites, observĂ©e dans deux contextes migratoires distincts : El Eulma, une ville du nord algĂ©rien et Marseille, mĂ©tropole du sud de la France. L'Ă©tude de cette minoritĂ© a permis de mesurer le rĂŽle que peut jouer lâidentitĂ© d'un groupe, sa cohĂ©sion sociale et le rĂ©seau migratoire qu'il a Ă©tabli, dans le dĂ©veloppement de lâaccueil des nouveaux migrants : comment ces caractĂ©ristiques se manifestent-elles pour favoriser lâintĂ©gration des nouveaux arrivants dans les territoires d'installation. AprĂšs une brĂšve prĂ©sentation de la communautĂ© mozabite et ses spĂ©cificitĂ©s culturelles, sont analysĂ©es les initiatives dĂ©veloppĂ©es par ses membres pour favoriser lâaccueil et lâintĂ©gration des nouveaux arrivants dans les deux villes dâaccueils
Numerical Simulation of Luminescent Downshifting in Top Cell of Monolithic Tandem Solar Cells
The increase in the conversion efficiency of monolithic tandem solar cells is limited by the short-circuit current density matching between the top and the bottom cells. Generally, the top cell presents the lowest current in the two subcells. In this paper, in order to increase the short-circuit current density in the top cell, we present a theoretical survey of the luminescence downshifting (LDS) approach for the design of monolithic tandem solar cells. The photovoltaic (PV) glass encapsulation material is replaced with a polymer material of polymethyl methacrylate (PMMA) type which is doped with diverse kinds of organic dyes. The performance of the n-p-p+ GaInP structure has been simulated as a function of the organic dyes. Gains achieved for the short-circuit current density and conversion efficiency are, respectively, 13.13% and 13.38%, under AM1.5G illumination spectra
Study of Thin Film Solar Cells in High Temperature Condition
AbstractIn this paper, we study the effect of temperature on the Copper Indium Gallium Selenide (CIGS) thin film solar cells using the one dimensional solar cells simulator SCAPS-1D (Solar Cell Capacitance Simulator). The dependence of the CIGS solar cells characteristics on temperature was investigated from 25°C to 70°C at intervals of 5°C. We observed an apparent degradation in the open-circuit voltage and conversion efficiency with an increase of temperature from 25°C to 70°C, accompanied with degradation in the maximum power of the cell from 18.55 mW/cm2 (25°C) to 14.941 mW/cm2 (70°C). By the using of the luminescent downshifting approach, the conversion efficiency of the CIGS solar cell was enhanced under Standard Test Conditions (STC) at 25°C and in high ambient temperatures test conditions. The coefficient of the voltage variation to temperature ÎVoc /ÎT was reduced from -2 to â1.8 (mV/°C)