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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Un cadre d’analyse interactionniste pour éclairer le rapport entre la formation et l’insertion professionnelle des candidats à l’enseignement au Québec

Bihan, Alain Christophe 08 1900 (has links)
Ce mémoire est une recherche théorique qui tire son origine du constat selon lequel il est difficile d’analyser la réalisation du projet professionnel des candidats à l’enseignement. Tel est le cas en raison des particularités contextuelles et des pluralités théoriques relatives aux notions de formation et d’insertion. À partir de ce constat, ce mémoire propose un cadre d’analyse permettant de comprendre comment les jeunes enseignants du Québec appréhendent le « rapport entre » leur formation et leur insertion face aux différentes contraintes (i.e. rigidité du système institutionnel de la formation, marché de l’insertion fluctuant et saturé, etc.) et aux ressources disponibles (i.e. programme d’études, cours, etc.) pour réaliser leur projet professionnel. Il repose sur l’hypothèse selon laquelle, pour réaliser leur projet professionnel, les candidats à l’enseignement mobilisent des stratégies afin de négocier les contraintes et ressources de leurs contextes respectifs. Dans cette optique, la démarche de cette recherche théorique s’inscrit dans une perspective interactionniste, telle qu’elle est véhiculée par la tradition de Chicago (Chapoulie, 2001). Quelques postulats sont mobilisés pour baliser les différentes étapes d’élaboration du cadre d’analyse. Le premier postulat considère que le « point de vue » de l’acteur est prépondérant pour comprendre ses conduites (Morrissette, Guignon & Demaziére, 2011). Cela amène à articuler les ancrages théoriques nécessaires à l’élaboration du cadre d’analyse en croisant une sociologie interactionniste avec une sociologie de l’action. Plus particulièrement, les concepts de « définition de la situation » de Thomas (1923) et de la « représentation de soi » de Goffman (1969) sont mis à profit. Les notions de coopération, d’incertitude et de rationalité, tirées du modèle de l’acteur stratégique de Crozier et Friedberg (1981), viennent compléter les assises de la modélisation d’une trame de négociation (Strauss & Baszanger, 1992). Le deuxième postulat considère que les contextes, sont prépondérants pour expliquer les conduites humaines (Abbott, 1999). Ces contextes, dits «éloignés» et «rapprochés» de l’acteur, constituent le « contexte d’action » (Strauss & Baszanger, 1992). Ce faisant, ils influent sur les stratégies mobilisées par l’acteur candidat à l’enseignement. Le troisième postulat considère que le monde social est animé par des processus (re)créés au travers des interactions entre acteurs (Morrissette & Guignon, 2014). Il amène à envisager la formation et l’insertion comme des processus sujets à des redéfinitions continues. Cela conduit à repenser la réalisation du projet professionnel des candidats à l’enseignement sous l’angle du « rapport entre ». Ces trois postulats structurent le cadre d’analyse qui se présente comme une « trame de négociation ». Il est développé pour éventuellement éclairer les stratégies de négociation mobilisées en contexte par les candidats québécois à l’enseignement pour réaliser leur projet professionnel. / This thesis is a theoretical research that originated from the observation that it is difficult to analyze the completion of the professional project of Quebec teacher candidates. This is the case because of the contextual features and theoretical plurality of concepts relating to training and workplace insertion. From this observation, this purpose thesis is to develop an analytical framework to understand how Quebec teacher candidates comprehend the “relationship between” their training and professional insertion with regards to various constraints (i.e. a rigid institutional training system, a fluctuating and saturated professional market, etc.) and the available resources (i.e. curriculum, courses, etc..) to achieve their professional project. It is based on the assumption that, to achieve their professional project, teacher candidates mobilize strategies to negotiate constraints and resources in their respective contexts. Accordingly, the approach of the theoretical research is part of an interactionist perspective as conveyed by the tradition of Chicago (Chapoulie, 2001); Some postulates are mobilized to mark out the various stages of development of the theoretical framework. The first postulate considers that the point of view of the actor is paramount to understanding its conduits (Morrissette, Guignon & Demazière, 2011). It leads to articulate the theoretical anchorings necessary for the development of the analytical framework by combining an interactionist sociology with a sociology of action. More specifically, the concepts of “definition of the situation” from Thomas (1923) and “representation of oneself” from Goffman (1969) are utilized. The concepts of cooperation, uncertainty and rationality drawn from the strategic actor model of Crozier and Friedberg (1981), come to supplement the foundations of the modeling of a frame of negotiation (Strauss & Baszanger, 1992). The second postulate considers that the contexts are paramount to explain human conduits (Abbott, 1999). These contexts, which are identified as distant contexts and closer contexts to the actor (Strauss & Baszanger, 1992), provide the action context. In doing so, they influence the strategies used by the actor teacher candidate. The third postulate considers that the social world is driven by processes recreated through the interaction between actors (Morrissette & Guignon, 2014). It takes into consideration that training and integration are subject to the continuous redefinition process. Accordingly, it is about rethinking the achievement of the professional project of teacher candidates in terms of the “relationship between”. These three postulates structure the presentation of an analytical framework that is called a “frame of negotiation”. It is developed to possibly inform the strategies of negotiation mobilized by Quebec teacher candidates in the action context to achieve their professional projects.
12

Vehicular ad hoc networks : dissemination, data collection and routing : models and algorithms

Soua, Ahmed 22 November 2013 (has links) (PDF)
Each day, Humanity loses thousands of persons on roads when they were traveling to work, to study or even to distract. The financial cost of these injuries is also terrifying: Some statistics evaluate the financial cost of vehicle accidents at 160 billion Euro in Europe each year. These alarming figures have driven researchers, automotive companies and public governments to improve the safety of our transportation systems and communication technologies aiming at offering safer roads and smooth driving to human beings. In this context, Vehicular Adhoc Networks, where vehicles are able to communicate with each others and with existent road side units, emerge as a promising wireless technology able to enhance the vision of drivers and offer larger telematic horizon. VANETs promising applications are not only restricted to road safety but span from vehicle trafficoptimization like flow congestion control to commercial applications like file sharing and internet access. Safety applications require that their alert information is propagated to the concerned vehicles (located in the hazardous zone) with little delay and high reliability. For these reasons, this category of applications is considered as delay sensitive and broadcast-oriented nature. While classical blind flooding is rapid, its major drawback is its huge bandwidth utilization. In this thesis, we are interested on enhancing vehicular communications under different scenarios and optimizations: First, We focus on deriving a new solution (EBDR) to disseminate alert messages among moving vehicles while maintaining it efficient and rapid. Our proposal is based on directional antennas to broadcast messages and a route guidance algorithm to choose the best path for the packets. Findings confirmed the efficiency of our approach in terms of probability of success and end-to-end delays. Moreover, in spite of the broadcast nature of the proposed technique, all transmissions stop very soon after the arrival of a packet to its destination representing a strong feature in the conception of EBDR. Second, we propose a novel mathematical framework to evaluate the performance of EBDR analytically. Although most of the proposed techniques present in literature use experimental or simulation tools to defend their performance, we rely here on mathematical models to confirm our achieved results. Our proposed framework allows to derive meaningful performance metrics including the probability of transmission success and the required number of hops to reach thefinal destination. Third, we refine our proposed broadcast-based routing EBDR to provide more efficient broadcasting by adjusting the transmission range of each vehicle based on its distance to the destination and the local node density. This mechanism allows better minimization of interferences and bandwidth's saving. Furthermore, an analytical model is derived to calculate thetransmission area in the case of a simplified node distribution. Finally, we are interested on data collection mechanisms as they make inter-vehicle communications more efficient and reliable and minimize the bandwidth utilization. Our technique uses Q-learning to collect data among moving vehicles in VANETs. The aim behind using the learning technique is to make the collecting operation more reactive to nodes mobility and topology changes. For the simulation part, we compare it to a non-learning version to study the effect of the learning technique. Findings show that our technique far outperforms other propositions and achieves a good trade off between delay and collection ratio. In conclusion, we believe that the different contributions presented in this Thesis will improve the efficiency of inter-vehicle communications in both dissemination and data collection directions. In addition, our mathematical contributions will enrich the literature in terms of constructing suitable models to evaluate broadcasting techniques in urban zones
13

Développement d’une grille pour l’analyse de la culture e-learning dans des forums de discussion en ligne

Leonelli, Andrea 12 1900 (has links)
La formation à distance (FAD) est de plus en plus utilisée dans le cadre de la formation des enseignants aux technologies de l’information et de la communication (TIC). Dans les pays en voie de développement, elle permet non seulement de réduire les coûts par rapport à une formation traditionnelle, mais aussi de modéliser des pratiques pédagogiques exemplaires qui permettent de maximiser le recours aux TIC. En ce sens, la formation continue des enseignants aux TIC par des cours à distance qui intègrent des forums de discussion offre plusieurs avantages pour ces pays. L’évaluation des apprentissages réalisés dans les forums reste cependant un problème complexe. Différents modèles et différentes procédures d’évaluation ont été proposés par la littérature, mais aucun n’a encore abordé spécifiquement la culture e-learning des participants telle qu’elle est définie par le modèle IntersTICES (Viens, 2007 ; Viens et Peraya, 2005). L’objectif de notre recherche est l’élaboration d’une grille opérationnelle pour l’analyse de la culture e-learning à partir des contenus de différents forums de discussion utilisés comme activité de formation dans un cours à distance. Pour développer cette grille, nous utiliserons une combinaison de modèles recensés dans la revue de littérature afin de circonscrire les principaux concepts et indicateurs à prendre en compte pour ensuite suivre les procédures relatives à l’analyse de la valeur, une méthodologie qui appelle la production d’un cahier des charges fonctionnel, la production de l’outil, puis sa mise à l’essai auprès d’experts. Cette procédure nous a permis de mettre sur pied une grille optimale, opérationnelle et appuyée par une base théorique et méthodologique solide. / The reality of a globally interconnected knowledge society is now possible by the continuous advances in Information and Telecommunications Technology (ICT) in which broadband availability has made possible for people to meet, discuss, learn, and innovate in virtual spaces: anywhere and anytime. For this society, the education system has no boundaries with virtual spaces used by educators and students alike to learn and exchange knowledge: the knowledge and role of the teachers in this case is fundamental to the successful development of this society. As such, distance learning is increasingly used for training teachers not only in ICT but also in the use of pedagogical tools that can improve the in-class learning. With the limited availability of physical exchanges, developing countries are main beneficiaries of distance education as it not only provides high quality learning as it attracts worldwide experts in its forums at a fraction of the costs when compared to the traditional face-to-face training but also allows for modeling best teaching practices that can maximize the benefits of ICT in the education system. In this sense, the ICT training of teachers in distance learning courses allows for a wide range and a high qualitative exchange in these discussion forums, which is a clear advantage for developing countries. The evaluation of learning achieved in the forums, however, remains a complex problem. Different models and assessment procedures have been proposed in a wide range of literature but none have specifically addressed the e-learning culture as defined by the model IntersTICES (Viens, 2007 ; Viens and Peraya, 2005). The aim of this research is to develop an analytical framework for the e-learning culture using the contents of discussion forums for training activities in distance learning courses. In developing this analytical framework, we reviewed and used a combination of models identified in the literature and categorized key concepts and indicators for a value analysis methodology and a function analysis system technique. As result, we developed the framework and tested it with experts in the field. This process allowed us to develop an analytical and operational framework supported by a solid theoretical basis.
14

Proposta de ferramental para análise nas perspectivas relacional e ética de estratégias políticas de empresas que operam em setores regulados: o caso do setor ferroviário brasileiro

Silva, Rodrigo Oliveira da 21 December 2016 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2018-04-10T11:48:01Z No. of bitstreams: 1 rodrigooliveiradasilva.pdf: 5997458 bytes, checksum: 0a46aa567e5e1847c47c94d1947e71db (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-04-11T11:12:08Z (GMT) No. of bitstreams: 1 rodrigooliveiradasilva.pdf: 5997458 bytes, checksum: 0a46aa567e5e1847c47c94d1947e71db (MD5) / Made available in DSpace on 2018-04-11T11:12:09Z (GMT). No. of bitstreams: 1 rodrigooliveiradasilva.pdf: 5997458 bytes, checksum: 0a46aa567e5e1847c47c94d1947e71db (MD5) Previous issue date: 2018-12-21 / PROQUALI (UFJF) / Esta pesquisa investiga o setor ferroviário de cargas brasileiro, especialmente no que tange às estratégias políticas das concessionárias do setor. A partir de 2010, mudanças na postura de atuação do órgão regulador, orientado por diretrizes do Governo Federal, trouxeram um impacto considerável no dia a dia das concessio-nárias ferroviárias de carga. A agência reguladora editou, em 2011, três resoluções que ficaram conhecidas como o “novo marco regulatório” do setor ferroviário de cargas. Logo após da edição de tais resoluções, em 2012, houve o primeiro processo de revisão tarifária do setor. Também em 2012, o Governo Federal lançou o Pro-grama de Investimento em Logística (PIL), em que o modelo atual de concessão, conhecido como de integração vertical, seria alterado para um modelo de passagem livre (open acess). Todas estas mudanças geraram uma intensa movimentação de atores do setor ferroviário de cargas. As concessionárias, juntamente com sua asso-ciação de representação de classe, tentaram influenciar, notadamente o órgão re-gulador, em relação aos impactos prejudiciais que tais medidas causariam às suas atividades. Já os usuários, também com o suporte de suas associações de represen-tação, apoiavam a decisão do órgão regulador em tentar minimizar os efeitos da atuação monopolista das concessionárias. Estes movimentos para influenciar o ator público com poder de decisão em determinada questão de política pública são cha-mados de estratégias políticas empresariais, cujo objetivo é gerar decisões políticas favoráveis à empresa ou ao setor ao qual ela pertence. O sucesso das estratégias políticas depende da construção de uma série de entrelaçamentos entre atores que podem influenciar direta ou indiretamente as decisões em políticas públicas e no marco legal e regulatório. Tais entrelaçamentos se constituem alianças estratégicas, que formatam a rede política de valor das empresas. Contudo, é imprescindível que as estratégias políticas estejam aderentes aos princípios da ética e integridade corporativa. Visando auxiliar as empresas que atuam em setores regulados, em especial as do setor ferroviário de cargas, esta pesquisa desenvolveu um ferramental analítico, na perspectiva relacional, de modo a contribuir para a gestão mais efetiva dessas empresas, considerando as particularidades institucionais do seu contexto e a necessidade de respeitar princípios éticos. Tal ferramental originou-se de uma fundamentação teórica, suportada pelas seguintes teorias: estratégias políticas, regulação econômica, ação coletiva, stakeholders, institucional, agência, redes e ética nos negócios. O ferramental analítico proposto foi refinado por meio de entrevistas com profissionais ligados ao setor ferroviário de cargas, pela análise em profundidade de três processos de mudança regulatória e pala aplicação parcial do ferramental analítico proposto em uma das empresas do setor. O método empregado para se alcançar o objetivo do trabalho foi o estudo de casos, em que se triangulou dados de entrevistas semiestruturadas, documentos públicos e registros em diversas mídias. Como principais resultados, a pesquisa pôde evidenciar os tipos de estratégias políticas empregadas pelas concessionárias ferroviárias de carga em processos específicos de mudança regulatória; a percepção dos entrevistados em relação ao ambiente regulatório; e a postura ética dos atores que compõem o setor ferroviário de cargas. Por fim, o ferramental analítico proposto se mostrou pertinente à realidade das empresas do setor. / This research investigates the Brazilian rail freight sector, especially regarding the strategies of the concessionaires of the sector. As of 2010, changes in the regulatory agency's position, guided by Federal Government guidelines, have brought a considerable impact without day to day rail freight concessions. In 2011, the regulatory agency issued three resolutions that became known as the "new regulatory framework" of the rail freight sector. Soon after the issuance of these resolutions, in 2012, there was the first process of tariff revision of the sector. Also in 2012, the Federal Government launched the Logistics Investment Program (PIL), in which the current concession model, known as vertical integration, was changed to a free passage model. All these changes have generated an intense movement of airports of the railroad of loads. As concessionaires, with their association of class representation, they tried to influence, especially the regulatory body, in relation to the impacts. The users, also supported by their representative associations, supported a decision of the regulator to minimize the effects of the monopolistic performance of the concessions. These moves to influence public power with decision-making power in a particular public policy issue are directed at business strategies, its purpose is to generate business-friendly policy decisions or the quality sector. The success of political strategies depends on the construction of a series of interlacings between actors that can influence directly or indirectly as decisions in public policies and not legal and regulatory framework. Such interlinkages constitute strategic alliances, which form a political network of business value. However, it is imperative that policy strategies adhere to the principles of ethics and corporate integrity. Aiming to assist as companies that operate in regulated sectors, especially as the rail freight sector, this research developed a population analyst, from a relational perspective, in order to contribute to a more effective management companies, considering as institutional particularities of their context. Ethical principles. Such manipulation originated from a theoretical foundation, supported later theories: political strategies, economic regulation, collective action, stakeholders, institutional, agency, networks and business ethics. The analytical project proposed for refining by means of interviews with professionals related to the rail freight sector, for in-depth analysis of three processes of regulated change and partial application of the proposed analytical project in a company of the sector. The method used for the purpose of case studies, in which triangulated data from semi-structured interviews, public documents and records in various media. As the main results, the research could highlight the types of incentive systems used in freight rail concessions in specific processes of regulatory change; a perception of the interviewees regarding the regulatory environment; it is an ethical stance of the actors that compose the railroad cargo industry. Finally, the proposed proposal analyst was relevant to the reality of the companies in the sector.
15

Evaluating urban climate policies : A comparative case study of Stockholm and Dublin

Bohman, Jerker January 2020 (has links)
Climate change is a collective action problem that has been seen as something that needs a global solution. This has resulted in multilateral agreements, such as the Paris Agreement, which can largely be said to have been unsuccessful so far. This has led to an increased awareness of the potential of cities as being part of the solution. Cities are often seen as key sources of climate change, but also as key sites for climate action. The Paris Agreement needs to be implemented on all political levels to be effective. This makes cities an important site for climate policy implementation. Some scholars of urban climate governance have looked at ways to evaluate climate policies in cities as a way to improve these processes. This study means to contribute to that field. The aim of the study is to evaluate climate policies in the city plans of Stockholm and Dublin. This has been done by testing an analytical framework which made it possible to shed light on the strengths and weaknesses of the climate policies and the governance structures in the plans. By doing this it was also possible to identify challenges in using the framework and give suggestions on how the framework can be improved. The study takes the form of a comparative case study of the two cities. Document analysis was used as a method to select and analyse the data and the empirical material consisted of the city plans of Stockholm and Dublin. These are policy documents containing general development plans of the cities. It was concluded that both plans contain both strengths and weaknesses. Examples of strengths are that both plans are well-integrated with activities on the regional and national level, that responsibility for implementation is centralised on the local level, that the plans promote innovation and that the plans are connected to long-term goals and visions. Examples of weaknesses are that neither plan makes use of more hard methods such as regulation, that the Dublin City Plan is not integrated with policy on the global level and that the Stockholm City Plan lacks monitoring systems. Regarding the analytical framework it was concluded that it can be used to analyse city plans rather than metropolitan plans. By testing the framework it was also possible to identify challenges in using the framework and give suggestions on how to improve it, such as by making some of the key attributes of the plan more widely applicable.
16

Vehicular ad hoc networks : dissemination, data collection and routing : models and algorithms / Réseaux véhiculaires : dissémination, routage et collecte de données : modèles et algorithmes

Soua, Ahmed 22 November 2013 (has links)
Chaque jour, l'humanité perd des milliers de personnes sur les routes pendant qu'ils se rendaient à travailler, à étudier ou même à se distraire. Ce nombre alarmant s'accumule avec le coût financier terrifiant de ces décès: Certaines statistiques évaluent le coût à 160 milliards d'euros par an en Europe. Dans ce contexte, les réseaux véhiculaires (VANETs) émergent comme une technologie sans fil prometteuse capable d'améliorer la vision des conducteurs et ainsi offrir un horizon télématique plus vaste. Les applications de sécurité routière exigent que le message d'alerte soit propagé de proche en proche par les véhicules jusqu'à arriver à la zone concernée par l'alerte tout en respectant les délais minimaux exigés par ce type d'applications et la grande fiabilité des transmissions. Dans cette thèse, nous nous intéressons à l'amélioration de l'efficacité des communications inter-véhiculaires sous différents scénarios: tout d'abord, nous nous concentrons sur le développement d'une nouvelle solution, appelée EBDR, pour disséminer les informations d'alertes dans un réseau VANET tout en assurant des courts délais de bout en bout et une efficacité pour les transmissions. Notre proposition est basée sur des transmissions dirigées effectuées à l'aide des antennes directionnelles pour la diffusion des messages et un algorithme de guidage d'itinéraire afin de choisir le meilleur chemin pour le paquet. En dépit de son fonctionnement en diffusion, les transmissions de notre technique s'arrêtent très rapidement après l'arrivée du paquet à la destination finale ce qui représente une caractéristique fondamentale dans la conception d’EBDR. Deuxièmement, nous proposons un framework mathématique ayant pour objectif l'évaluation des performances d’EBDR analytiquement. Nos modèles analytiques permettent de dériver des métriques de performances significatives à savoir la probabilité de succès et le nombre de sauts requis pour atteindre la destination finale. En outre, nous proposons une amélioration de notre protocole EBDR dans le but de fournir une diffusion plus efficace. Pour cela, nous nous basons sur l'ajustement de la puissance de transmission de chaque véhicule en fonction de la distance qui le sépare de la destination et la densité locale des nœuds. Ce mécanisme de contrôle de congestion permet de mieux minimiser les interférences et économiser de la bande passante. En plus, un modèle mathématique a été élaboré pour calculer la surface de la zone de transmission dans le cas d'une distribution uniforme des nœuds. Finalement, nous nous sommes intéressés aux mécanismes de collecte de données dans les réseaux véhiculaires. Notre approche est basée sur l'utilisation du principe du Q-learning pour la collecte des données des véhicules en mouvement. L'objectif de l'utilisation de ce mécanisme d'apprentissage est de rendre l'opération de collecte mieux adaptée à la mobilité des nœuds et le changement rapide de la topologie du réseau. Notre technique a été comparée à des méthodes n'utilisant pas du "learning", afin d'étudier l'effet du mécanisme d'apprentissage. Les résultats ont montré que notre approche dépasse largement les autres propositions en terme de performances et réalise un bon compromis entre le taux de collecte et les délais de bout en bout. Pour conclure, nous pensons que nos différentes contributions présentées tout le long de cette thèse permettront d'améliorer l'efficacité des communications sans fil inter-véhiculaires dans les deux directions de recherches ciblées par cette thèse à savoir : la dissémination des messages et la collecte des données. En outre, nos contributions de modélisation mathématique enrichiront la littérature en termes de modèles analytiques capables d'évaluer les techniques de transmission des données dans un réseau véhiculaire / Each day, Humanity loses thousands of persons on roads when they were traveling to work, to study or even to distract. The financial cost of these injuries is also terrifying: Some statistics evaluate the financial cost of vehicle accidents at 160 billion Euro in Europe each year. These alarming figures have driven researchers, automotive companies and public governments to improve the safety of our transportation systems and communication technologies aiming at offering safer roads and smooth driving to human beings. In this context, Vehicular Adhoc Networks, where vehicles are able to communicate with each others and with existent road side units, emerge as a promising wireless technology able to enhance the vision of drivers and offer larger telematic horizon. VANETs promising applications are not only restricted to road safety but span from vehicle trafficoptimization like flow congestion control to commercial applications like file sharing and internet access. Safety applications require that their alert information is propagated to the concerned vehicles (located in the hazardous zone) with little delay and high reliability. For these reasons, this category of applications is considered as delay sensitive and broadcast-oriented nature. While classical blind flooding is rapid, its major drawback is its huge bandwidth utilization. In this thesis, we are interested on enhancing vehicular communications under different scenarios and optimizations: First, We focus on deriving a new solution (EBDR) to disseminate alert messages among moving vehicles while maintaining it efficient and rapid. Our proposal is based on directional antennas to broadcast messages and a route guidance algorithm to choose the best path for the packets. Findings confirmed the efficiency of our approach in terms of probability of success and end-to-end delays. Moreover, in spite of the broadcast nature of the proposed technique, all transmissions stop very soon after the arrival of a packet to its destination representing a strong feature in the conception of EBDR. Second, we propose a novel mathematical framework to evaluate the performance of EBDR analytically. Although most of the proposed techniques present in literature use experimental or simulation tools to defend their performance, we rely here on mathematical models to confirm our achieved results. Our proposed framework allows to derive meaningful performance metrics including the probability of transmission success and the required number of hops to reach thefinal destination. Third, we refine our proposed broadcast-based routing EBDR to provide more efficient broadcasting by adjusting the transmission range of each vehicle based on its distance to the destination and the local node density. This mechanism allows better minimization of interferences and bandwidth's saving. Furthermore, an analytical model is derived to calculate thetransmission area in the case of a simplified node distribution. Finally, we are interested on data collection mechanisms as they make inter-vehicle communications more efficient and reliable and minimize the bandwidth utilization. Our technique uses Q-learning to collect data among moving vehicles in VANETs. The aim behind using the learning technique is to make the collecting operation more reactive to nodes mobility and topology changes. For the simulation part, we compare it to a non-learning version to study the effect of the learning technique. Findings show that our technique far outperforms other propositions and achieves a good trade off between delay and collection ratio. In conclusion, we believe that the different contributions presented in this Thesis will improve the efficiency of inter-vehicle communications in both dissemination and data collection directions. In addition, our mathematical contributions will enrich the literature in terms of constructing suitable models to evaluate broadcasting techniques in urban zones
17

Stratégie d’internationalisation d’une Petite Economie Mature Ouverte (PEMO) : le cas du Luxembourg : déterminants, défis et leviers / Strategy for the internationalisation of a small open mature economy (SOME) : the case of Luxembourg : key elements, challenges and levers

Hostert, Marc 18 October 2013 (has links)
L’attractivité des territoires vis-à-vis des investissements directs étrangers constitue, avec l’ouverture accrue des espaces économiques et politiques, un élément clé de l’intensification des flux d’échanges et d’investissements.Pour tous les pays et, plus particulièrement, pour ceux ne disposant pas d’un marché national important, l’établissement d’un diagnostic d’attractivité et la détermination d’axes prioritaires de développement constituent une démarche fondamentale applicable particulièrement à l’exemple du Luxembourg, une économie considérée comme une petite économie mature ouverte (PEMO).A travers cette recherche, on s’attachera à appliquer et à adapter un modèle d’analyse des fondements de l’attractivité, puis un modèle de détermination des orientations économiques et institutionnelles à privilégier.Cette recherche conduit à définir une démarche prospective structurée, appliquée à la PEMO considérée :- en partant de l’établissement d’une liste de déterminants de compétitivité et d’attractivité ayant potentiellement trait à une PEMO en général, validée ensuite pour le cas concret du Luxembourg par un panel de décideurs ;- en permettant l’établissement d’un diagnostic d’attractivité portant sur la situation actuelle de la PEMO considérée ;- pour déboucher sur la détermination d’activités prioritaires et de profilsd’investisseurs directs étrangers à privilégier, dans un « espace de référence » géo - sectoriel reconsidéré.Cette recherche devrait permettre d’identifier les secteurs d’investissement les plus attractifs pour les entreprises étrangères dans une PEMO comme le Luxembourg. / Together with increased economic and political openness, a location’s or territory’s attractiveness and competitiveness for foreign direct investment (FDI) are key elements for intensifying investment and trade flows.For countries, especially those without a national market of significant scale, establishing a way to identify and analyse priorities for economic development is fundamental.This research defines a general analytical framework applicable to the concepts of attractiveness and competitiveness, and, building on this framework, develops a specific model that could assist key institutions as to identify their preferred orientations in the specific context of an economy considered as a small open mature economy (SOME), in particular, Luxembourg.This research will lead to the definition of a prospective structured approach by:- providing a list of factors which potentially influence the competitiveness and attractiveness of SOMEs; this list having been validated with respect to Luxembourgby national decision makers;- establishing a method for analysing the current situation regarding attractiveness and competitiveness in Luxembourg; and- identifying priority sectors for FDI that could be targeted in a specific location/territory of reference such as Luxembourg.
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The impact of instructional leadership on the culture of teaching and learning in rural schools of the Eastern Cape

Yobe, Abigail 15 November 2019 (has links)
The purpose of this research is to examine the impact of instructional leadership on the culture of teaching and learning in ten rural schools of the Eastern Cape categorised as performing and under performing schools. The research utilises the transformational leadership theory in its theoretical analytical framework as the model for effective leadership. The research argues that principals’ instructional leadership can significantly improve teacher engagement, teacher collaboration and learner performances in the ten rural schools. The study draws on the qualitative research methodology, instruments utilised are interviews of teachers, principals and top education officials within the Buffalo City Municipality. Past matric results of the rural schools under consideration were retrieved from the archives of the National Senior Certificate Results to measure the impact of instructional leadership on the culture of teaching and learning and learners’ performances. The study concludes that there is a relationship between instructional leadership and learners’ outcomes. / Educational Management and Leadership / M. Ed. (Educational Leadership and Management)

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