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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.
161

A qualidade no Programa Universidade Para Todos (PROUNI) segundo os resultados de avaliação de cursos do Sistema Nacional de Avaliação da Educação Superior (SINAES) / Quality in the Program University for All (ProUni) according to the course assessment results by the National Higher Education Assessment System (SINAES)

Camila Yuri Santana Ikuta 24 May 2016 (has links)
A presente pesquisa teve como objetivo discutir a questão da qualidade dos cursos que ofertam bolsas no Programa Universidade para Todos (ProUni). O ProUni é uma política educacional desencadeada pelo Governo Federal e implementada em 2005. É voltada ao segmento de educação superior, possuindo como uma de suas premissas a democratização do acesso, realizando a concessão de bolsas de estudos para estudantes de cursos de graduação e sequenciais de formação específica em Instituições de Ensino Superior (IES) privadas em todo o país. O referencial teórico foi construído em torno da revisão bibliográfica de quatro temas: a trajetória da educação superior brasileira; as políticas de avaliação, em especial o Sistema Nacional de Avaliação da Educação Superior (SINAES); a discussão conceitual sobre qualidade da educação superior; e o debate em torno da política do Programa Universidade para Todos. No desenvolvimento da pesquisa foram utilizados procedimentos metodológicos quantitativos, por meio da análise de dados sobre os cursos que ofertaram bolsas pelo ProUni no município de São Paulo-SP, no primeiro semestre de 2014, em relação aos resultados do Conceito Preliminar de Curso (CPC), considerado o indicador oficial de avaliação da qualidade dos cursos superiores brasileiros. Foi constatado nos resultados que, no caso do grupo de cursos ProUni selecionado, nem sempre apresentam-se resultados ligados à baixa qualidade (considerando como referência de qualidade o CPC). Verificou-se que há concentração predominante na faixa 3 do indicador, considerada satisfatória; entretanto, há menos cursos na faixa 4 e um número bastante reduzido na faixa 5, que são consideradas como as que possuem maior relação com os critérios de qualidade exigidos. Também, há uma parcela menor de cursos com ausência de conceito ou de reconhecimento, o que pode trazer incertezas sobre a qualidade ofertada. Além disso, a correspondência com os critérios de qualidade utilizados mostrou-se desigual quando foram consideradas variáveis como o grau acadêmico (bacharelados e tecnólogos), o tipo de bolsa ofertada (integral ou parcial) e a área de enquadramento dos cursos. Ao realizar uma comparação entre o grupo de cursos ProUni selecionado, em relação com os demais cursos avaliados pelo CPC, em São Paulo-SP e no Brasil, observou-se que os cursos ProUni acompanharam a tendência de resultados dos demais cursos, e em alguns casos, apresentaram inclusive resultados melhores em relação às faixas do CPC. Diante desse quadro, finaliza-se com uma discussão em torno dos limites e possibilidades da avaliação da qualidade dos cursos no ProUni, considerando a literatura sobre esses temas. / The objective of this study was the quality of the courses that offer scholarships through the Program University for All (ProUni). ProUni is an educational policy unleashed by the Federal Government and implemented in 2005. It is intended for higher education with the assumption of democratizing the access by granting scholarships to undergraduates for further specific training in private Higher Education Institutions (IES) all over Brazil. The theoretical framework includes the bibliographical review regarding four topics: the trajectory of higher education in Brazil; the assessment policies, especially the National Higher Education Assessment System (SINAES); the conceptual discussion of quality in higher education; and the debate around the policy of the Program University for All. The methodological procedures of this research were quantitative and analyzed data about the degrees that provide scholarships through ProUni in the city of São Paulo-SP, along the first semester of 2014, in relation to the results of the Preliminary Course Grade (CPC), considering the official indicator of the quality assessment for the Brazilian higher education degrees. The results have shown that, in the case of the ProUni courses selected, not always results were associated with low quality (taking CPC as quality reference). There was a predominant concentration on level 3 of the indicator, considered satisfactory; however, there are less degree courses on level 4 and a rather reduced number on level 5, which are defined as the levels with more compliance with the required quality criteria. Also, there is smaller group of degrees with no grade assigned or officially recognized by the educational authority, which may bring uncertainties about the quality provided by such courses. In addition, the correspondence with the quality criteria utilized turned out to be unequal when considering variables such as the academic level (professional or technical degree), the type of scholarship offered (full or partial) and the framing area of the courses. By comparing the group of ProUni degrees selected, in relation to other degrees assessed by CPC, in São Paulo-SP and in Brazil, it was found that ProUni courses went along the trend of other courses in terms of assessment results, and in some cases, they had better results regarding the CPC levels. Faced with this situation, there is a final discussion around the limits and possibilities of quality assessment for ProUni degree courses, taking the literature covering these topics into consideration.
162

Contribuição à avaliação da estabilidade global e pré-dimensionamento de pórticos planos em concreto pré-moldado / Contribution to the assessment of global stability and preliminary design of precast concrete frames

Fernando de Faria Vecchio Lins 01 July 2013 (has links)
O presente trabalho tem como objetivo desenvolver processos analíticos e programas computacionais para avaliação da estabilidade global e pré-dimensionamento de pórticos planos em concreto pré-moldado com base na garantia da estabilidade global. Em relação à avaliação da estabilidade global, são propostas duas expressões. A primeira está relacionada à expressão do limite do parâmetro de estabilidade aplicada a pórticos planos em concreto pré-moldado. A segunda expressão tem o objetivo determinar o deslocamento horizontal de topo de pórticos planos em concreto pré-moldado de um pavimento. A expressão do limite alternativo do parâmetro de estabilidade é deduzida a partir dos valores obtidos da relação entre o deslocamento horizontal médio e de topo de 1320 pórticos. A expressão é função do fator de restrição da ligação, contemplando, dessa forma, os efeitos causados pela semirrígidez das ligações no comportamento da estabilidade global desse sistema estrutural. A equação de determinação do deslocamento horizontal de topo de pórticos planos em concreto pré-moldado de um pavimento é deduzida com base no método dos deslocamentos. Em relação ao pré-dimensionamento de pórticos planos em concreto pré-moldado, são propostos processos analíticos para o pré-dimensionamento dos pilares de pórticos de um pavimento com ligação semirrígida e de pórticos de múltiplos pavimentos com ligações rígidas e articuladas. Os processos analíticos são constituídos pela expressão da rigidez equivalente de estabilidade de pórticos, desenvolvida através das equações do parâmetro de estabilidade e do seu limite alternativo. O trabalho ainda apresenta o Programa de Avaliação da Estabilidade Global e Pré-dimensionamento de Pórticos Planos em Concreto Pré-moldado, denominado PRE-MOLDIM. O programa é constituído por quatro módulos. O primeiro módulo realiza a avaliação da estabilidade global e verificação da deslocabilidade lateral de pórticos planos em concreto pré-moldado. O segundo módulo tem o objetivo de definir as dimensões mínimas dos pilares em função da garantia da estabilidade global e do deslocamento lateral admissível. O terceiro módulo define o valor da rigidez das ligações necessário para que sejam atendidos os quesitos de estabilidade global e deslocamento lateral admissível. O quarto módulo realiza o dimensionamento da armadura de continuidade de uma típica ligação viga-pilar em concreto pré-moldado. O dimensionamento da armadura de continuidade é realizado em função da garantia da estabilidade global e do deslocamento lateral admissível de pórticos planos em concreto pré-moldado. A aplicação dos processos analíticos e programas computacionais em exemplos comprovaram, de forma satisfatória, o desempenho de suas funções. Os valores obtidos pela expressão alternativa do limite do parâmetro de estabilidade são compatíveis com o limite do coeficiente \'gama\'z. Os valores do deslocamento de topo de pórticos de um pavimento com ligações semirrígidas, obtidos pelo processo analítico, são próximos dos valores obtidos pela simulação numérica. Os pilares pré-dimensionados pelos processos analíticos conseguem garantir de forma satisfatória estabilidade global dos pórticos planos em concreto pré-moldado. / The present work aims to develop analytical processes and computer programs for the evaluation of global stability and preliminary design of plane frames in precast concrete based on ensuring global stability. Regarding the evaluation of global stability, two analytical expressions are proposed. The first is related to the expression of the limit of the stability parameter applied to plane frames in precast concrete. The second expression has the objective to determine the horizontal displacement of the top of plane frames in precast concrete for a floor. The expression of the alternative stability limit of the parameter is deduced from the values obtained from the relationship between the average and the top horizontal displacement of 1320 frames. The expression is a function of the limiting factor of the connection, thus contemplating the effects caused by the semi-rigidity of the connection on the global stability behavior of this structural system. The equation for determining the horizontal displacement of the top of plane frames in precast concrete pavement is obtained based on the displacement method. Regarding the preliminary design of plane frames in precast concrete, analytical procedures are proposed for the preliminary design of column of an one store frame with semi-rigid connection and a multiple store frames with rigid and articulated connections. The analytical processes are constituted by the expression of equivalent stiffness of frame stability, developed through the equations of the stability parameter and its alternative limit. The work also presents the Program of Global Stability Evaluation and Preliminary Design of Plane Frames in Precast Concrete, called PRE-MOLDIM. The program consists of four modules. The first module performs the evaluation of global stability and verification of lateral plane frames displaceability in precast concrete. The second module aims to set minimum dimensions for the pillars due to guarantee the global stability and check the allowable lateral displacement. The third module defines the value of the connections stiffness so the matter of global stability and allowable lateral displacement are satisfied. The fourth module performs the design of continuity armor of a typical beam-column connection in precast concrete. The design armour continuity is made on the basis of ensuring the global stability and lateral displacement allowable plane frames in precast concrete. The application of analytical processes and computer programs in examples proved satisfactorily, the performance of its functions. The values obtained by the alternative expression of the limit of stability parameter are compatible with the limit of the coefficient \'gama\'z. The offset values top venting a pavement with semi-rigid connections, obtained by the analytical process, are close to the values obtained by numerical simulation. The preliminary designed pillars by analytical processes can ensure a satisfactory global stability of the plane frames in precast concrete.
163

Aproveitamento dos resíduos gerados no tratamento preliminar de estações de tratamento de esgoto / Utilization of the waste generated in the preliminary treatment of sewage treatment plants

Nayara Batista Borges 28 November 2014 (has links)
Os sólidos grosseiros, sedimentáveis e flutuantes são removidos no sistema de tratamento preliminar de estações de tratamento de esgoto e, de forma geral, dispostos em aterros sanitários e lixões, sem preocupação relacionada ao seu potencial de aproveitamento, redução, recuperação e impactos ambientais. Apesar da falta de importância atribuída, esses resíduos se mostram um dos problemas no gerenciamento de estações no que se refere ao manuseio, tratamento e destinação final. Nesse contexto, a presente pesquisa tem como objetivo demonstrar a potencialidade do aproveitamento dos resíduos removidos no tratamento preliminar de Estações de Tratamento de Esgoto (ETE), tomando-se como referência a ETE Monjolinho em São Carlos-SP (com capacidade de atendimento de 258.000 habitantes). Para atingir este propósito, foi avaliada a potencialidade do uso dos materiais removidos na unidade do tratamento preliminar, como fontes de energia e de matéria-prima, enfocando tema pouco explorado. Foram estudados os resíduos: i) removidos nos gradeamentos grosseiro e fino, visando seu uso como combustível; ii) o material sedimentável retido nos desarenadores, com intuito de utilizá-lo como agregado para argamassa e concreto não estrutural na construção civil; e, iii) os óleos e graxas removidos, visando o seu aproveitamento como insumo para produção de biocombustível; e também foi avaliada a degradação aeróbia e anaeróbia deste tipo de material. Em relação a cada tipo de resíduo foi possível verificar: i) a potencialidade da geração de energia a partir dos resíduos removidos nos gradeamentos de estações de tratamento de esgoto, tendo em vista os elevados resultados do poder calorífico inferior (4.837 kcal.kg-1 para resíduos do gradeamento grosseiro e 5.059 kcal.kg-1 para resíduos do gradeamento fino) e baixos valores na geração de cinzas (15,91% para resíduos do gradeamento grosseiro e 9,60% para resíduos do gradeamento fino); ii) a viabilidade técnica, econômica e ambiental da utilização da areia residual, removida nos desarenadores de ETEs, como agregado miúdo na incorporação de argamassas para revestimento e preparação de concreto não estrutural, desde que seja submetida ao procedimento de limpeza e secagem; iii) não foi possível obter biodiesel a partir do material flutuante removido nos desarenadores, uma vez que esse resíduo apresentou baixa concentração de óleos e graxas se comparado à outras matérias primas e grande quantidade de sólidos, sendo esses, em boa parte, de natureza orgânica, em consequência disso foi comprovada a potencialidade da degradação aeróbia e anaeróbia do material flutuante, resultando na redução de carga orgânica a ser aplicada nas unidades subsequentes do processo de tratamento. / The coarse, settleable and floating solids are removed in the system of preliminary treatment of the sewage treatment station and are generally disposed in landfills and dumps, regardless of their potential use, reduction, recovery and its environmental impacts. Despite the lack of recognizable relevance, such waste constitutes one of the problems in the management of stations with regard to the handling, treatment and disposal. In this context, the current investigation aims at demonstrating the potential of the use of the waste removed in the preliminary treatment of STPs, taking as reference the Monjolinho STP in Sao Carlos-Brazil (with service capacity of 258,000 population equivalent). To this end, we evaluated the potential use of the material removed in the primary treatment unit, as sources of energy and raw materials, focusing on underexplored topics. The following residues were studied: i) those removed in the coarse and fine screens, aiming its use as fuel; ii) the settleable material retained in the grit chambers, with the intention of using it as aggregate for mortar and nonstructural concrete in construction; and, iii) the oil and grease removed, using it a feedstock for biofuel production; and the aerobic and anaerobic degradations of such material were also evaluated. For each type of waste could be verified: i) the potential of generating energy from waste removed in the screens of the sewage treatment plant, due to the relatively high results of lower calorific value (4,837 kcal.kg-1 for waste collected in the coarse screens and 5,059 kcal.kg-1 for the fine screening residue) and low values regarding the generation of ash (15.91% and 9.60% for the coarse and fine screening, respectively); ii) technical, economic and environmental feasibility of the use of residual sand, removed in the grit chambers, as fine aggregate in the incorporation of mortars for coating and preparation of non-structural concrete, provided that it is submitted to cleaning and drying procedures; iii) it was not possible to obtain biodiesel from the floating material removed in the grit chambers, since this residue showed low concentration of oils and greases when compared to other raw materials and a high content of solids, largely organic in nature. Therefore, it was proved the potential for aerobic and anaerobic degradation of the floating material, resulting in the reduction of the organic load to be applied in the subsequent treatment process units.
164

Intégration de la maturité des connaissances dans la prise de décision en conception mécanique : application à un système solaire. / Integration of knowledge maturity in decision making for mechanical design : application to a solar system.

El amine, Mehdi 16 December 2015 (has links)
La réussite du développement des produits industriels a un enjeu économique considérable pour l’entreprise. Les décisions sur les concepts et sur l’architecture du produit ont un impact considérable sur le coût global du cycle de vie du produit. Les industriels sont alors de plus en plus encouragés à adopter des méthodes permettant de rationaliser les décisions de conception. Ces méthodes doivent être en adéquation avec le niveau de connaissance acquis sur les alternatives de conception, la nature des décisions à prendre et les outils d’évaluation disponibles. Ainsi, deux méthodes d’aide à la décision ont été développées dans cette thèse en fonction de la phase de conception étudiée.Une première méthode est proposée pour la phase amont de conception dans laquelle l’objectif de l’entreprise est de réduire le nombre de concepts proposés initialement pour concentrer ses efforts et ses ressources sur les concepts les plus prometteurs. Durant cette phase, les produits sont définis d’une manière très imprécise. Les concepteurs doivent alors faire beaucoup d'hypothèses lorsqu’ils proposent des modèles de comportement destinés à évaluer les concepts. Ces modèles, qui expriment une connaissance de nature explicite, sont insuffisants pour faire des choix de concepts. Pour remédier à cette difficulté, nous nous orientons dans notre étude vers la connaissance implicite (ou subjective), obtenue au travers de l'expérience et du savoir-faire acquis par les concepteurs. Afin d’intégrer cette connaissance dans la prise de décision, elle est d’abord formalisée au travers d’outils comme les fonctions de préférence. La méthode globale d’aide à la décision proposé permet de combiner à la fois cette connaissance implicite et la connaissance explicite (représentée par les modèles de comportement) pour évaluer chaque concept en termes d’aptitude à respecter les exigences minimales de validation et du niveau d’adéquation avec les objectifs de conception. Les objectifs et préférences des décideurs sont, quant à eux, structurés et formalisés au travers du modèle OIA (Observation-Interprétation-Agrégation) développé auparavant dans le laboratoire I2M-IMC.Une deuxième méthode a été proposée pour la phase aval de conception qui a pour objectif de fixer les paramètres du produit final (choix des matériaux, dimensions, etc.) après que le concept ait été choisi. Durant cette phase, le produit est défini d’une manière plus précise et les modèles de comportement sont plus représentatifs des phénomènes physiques pertinents du concept étudié. Ces modèles restent cependant basés sur des hypothèses qui conduisent parfois à une remise en question de leur exactitude, surtout pour certains paramètres de conception. Fixer les paramètres du produit en se basant uniquement sur ces modèles de comportement nécessite la prise en compte de leur niveau exactitude. Nous avons donc développé un indicateur d’exactitude de ces modèles qui intègre, d’une part, une évaluation objective qui est la mesure d’écart entre le modèle et un comportement de référence (supposé exact) et, d’autre part, sur une évaluation subjectif qui se base sur la mesure de distance avec la solution de référence (solution prototypée) et sur des fonctions de confiances établies par les concepteurs. La combinaison d’une évaluation objective et subjective de l’exactitude permet d’obtenir à la fin un indicateur général d’exactitude capable de couvrir l’intégralité de l’espace de conception. L’indicateur ainsi obtenu est utilisé dans une méthode d’aide à la décision qui qualifie chaque solution candidate en terme de risque engendré par les l’exactitude des modèles et de degré de satisfaction des objectifs de conception (en se basant la modèle OIA). / The successful development of industrial products has a considerable economic challenge for the company. Decisions on concepts and product architecture have a significant impact on the overall cost of the product life cycle. Manufacturers are then increasingly encouraged to adopt methods to streamline design decisions. These methods must be consistent with the level of knowledge acquired on alternative design, the nature of decision making and assessment tools available. Thus, both methods of decision support have been developed in this thesis based on the study design phase.A first method is proposed for the upstream design stage in which the goal of the company is to reduce the number of concepts initially proposed to focus its efforts and resources on the most promising concepts. During this phase, the products are defined very loosely. Designers must then make a lot of assumptions when proposing role models to assess the concepts. These models, which express a knowledge of explicit nature, are insufficient to make choices concepts. To overcome this difficulty, we are moving in our study to the implicit knowledge (or subjective), obtained through the experience and expertise acquired by the designers. To integrate this knowledge in decision-making, it is first formalized through tools such as preferably functions. The overall approach to decision support proposed for combining both the implicit knowledge and explicit knowledge (represented by the role models) to assess each concept in terms of ability to meet the minimum requirements for validation and level fitness with the design goals. The objectives and preferences of decision makers are, in turn, structured and formalized through the OIA model (Observation-Interpretation-Aggregation) previously developed in the laboratory I2M-BMI.A second method was proposed for the downstream design phase that aims to set the parameters of the final product (choice of materials, dimensions, etc.) after the concept was chosen. During this phase, the product is defined in a more precise manner and behavior patterns are more representative of the relevant physical phenomena of the concept studied. These models are however based on assumptions which sometimes lead to a questioning their accuracy, especially for some design parameters. Fix the product parameters based solely on these patterns of behavior requires taking into account their accuracy level. We have therefore developed an accuracy indicator of these models that integrates on the one hand, an objective assessment which is the measure of difference between the model and a reference behavior (assumed correct) and, secondly, on a subjective assessment that is based on the distance measurement with the reference solution (prototyped solution) and trusts functions established by the designers. The combination of objective and subjective assessment of the accuracy provides at the end a general indicator of accuracy able to cover the entire design space. The indicator thus obtained is used in a method of decision support that qualifies each candidate solution in terms of risk posed by the accuracy of the models and level of satisfaction of design objectives (based the model OIA) .
165

Problematické aspekty kritérií C.I.L.F.I.T. zakotvených v soudním rozhodnutí SD EU / Problematic aspects of the C.I.L.F.I.T. criterions enshrined in the CJEU's judgement

Sviatkin, Ivan January 2015 (has links)
The topic of the thesis are CILFIT criterions. These criterions were established by the Court of Justice of the European Union as conditions for application of the acte clair doctrine by national courts of last resort. The conditions determine situations in which such a court does not have an obligation under Article 267/3 to bring a matter before the Court of Justice. First of all, thesis describes the historical circumstances, which gave rise to the CILFIT case as well as the facts of that issue. Then it analyses one by one CILFIT criterions and also current procedure of submitting preliminary questions as a whole. As a part of the analysis, it focuses on the practical application of the abovementioned conditions by the courts of the Member States. It targets purely theoretical ideas too. The thesis, further, identifies certain problematic aspects of the CILFIT conditions. Subsequently, some possible solutions are being suggested and their effectiveness and appropriateness are being examined.
166

Le traitement des exceptions préliminaires devant le CIRDI

Seghiri, Abderrezak 09 1900 (has links)
De plus en plus soulevées, les exceptions préliminaires sont devenues aujourd’hui une institution classique du procès CIRDI. Leur utilisation croissante par les acteurs contentieux, et les multiples enjeux qu’elles recèlent, invitent résolument à s’interroger sur l’existence d’un réel régime juridique qui les encadre et, partant, qui permettrait de garantir un certain degré de prévisibilité. A cet égard, le volet procédural de l’exception renferme maints éléments problématiques. Certains sont liés à la mise en œuvre, d’autres au moment de l’introduction de l’exception. Ainsi, d’une part, cette étude s’intéressera aux motivations réelles derrière la consécration de la faculté de les soulever et aux acteurs contentieux qui en ont accès. D’autre part, ce mémoire se focalisera sur la réalité de l’exigence d’introduction in limine litis pour mieux cerner les dérogations fréquentes ainsi que la souplesse exagérée dont elle fait l’objet. Quant au volet substantiel, nous nous interrogerons sur l’objet de l’exception tant du point de vue de la qualification que du point de vue de la délimitation. Plus précisément, nous aborderons la question de la distinction entre compétence et recevabilité. Pourquoi cette distinction et tantôt observée, tantôt complètement ignorée par les parties au procès. Quel impact pourrait avoir une telle distinction sur le résultat escompté ? De même, nous nous nous interrogerons sur l’extension fréquente, parfois abusive, du champ de la compétence ou de la recevabilité afin de mieux appréhender les contours de l’objet, l’usage qu’en font les Tribunaux CIRDI et les raisons derrière un tel phénomène. / Increasingly used, preliminary objections have now become a traditional institution of ICSID proceedings. The increasing use by litigation actors raises many questions about the reality of their treatment. In particular, it raises questions about the existence of a consistent set of rules that would framework their use and, hence, ensure a certain degree of predictability. In this regard, the procedural aspect of the objections includes many problematic elements. Some are linked to the implementation of the objection, others to the introduction timing. Thus, on the one hand, this research will focus on the real incentives behind the consecration of the right to raise them and who has access to that right. On the other hand, this research will focus on the actuality of the condition to introduce them in limine litis and try to explain the frequent exceptions, and exaggerated flexibility, in the arbitral practice regarding this condition. As to the substantive aspect, we will inquire about the purpose of the objection from both qualification and delimitation point of views. Specifically, we will address the issue of the distinction between jurisdiction and admissibility. Why this distinction is sometimes considered and sometimes completely ignored by the parties to the proceedings. What impact might such a distinction have on the final outcome? Similarly, we will question the frequent extension, sometimes even abusive, of the scope of jurisdiction or admissibility by the ICSID Tribunals to help better understand the borders of the objections substance and the reasons behind such a phenomenon.
167

Amélioration des techniques d'optimisation combinatoire par retour d'expérience dans le cadre de la sélection de scénarios de Produit/Projet / Improvement of combinatorial optimization using experience feedback mechanism

Pitiot, Paul 25 May 2009 (has links)
La définition et l’utilisation d'un modèle couplant la conception de produit et la conduite du projet dès les phases amont de l’étude d’un système correspondent à une forte demande industrielle. Ce modèle permet la prise en compte simultanée de décisions issues des deux environnements produit/projet mais il représente une augmentation conséquente de la dimension de l'espace de recherche à explorer pour le système d'aide à la décision, notamment lorsque il s'agit d'une optimisation multiobjectif. Les méthodes de type métaheuristique tel que les algorithmes évolutionnaires, sont une alternative intéressante pour la résolution de ce problème fortement combinatoire. Ce problème présente néanmoins une particularité intéressante et inexploitée : Il est en effet courant de réutiliser, en les adaptant, des composants ou des procédures précédemment mis en œuvre dans les produits/projets antérieurs. L'idée mise en avant dans ce travail consiste à utiliser ces connaissances « a priori » disponibles afin de guider la recherche de nouvelles solutions par l'algorithme évolutionnaire. Le formalisme des réseaux bayésiens a été retenu pour la modélisation interactive des connaissances expertes. De nouveaux opérateurs évolutionnaires ont été définis afin d'utiliser les connaissances contenues dans le réseau. De plus, le système a été complété par un processus d'apprentissage paramétrique en cours d'optimisation permettant d'adapter le modèle si le guidage ne donne pas de bons résultats. La méthode proposée assure à la fois une optimisation plus rapide et efficace, mais elle permet également de fournir au décideur un modèle de connaissances graphique et interactif associé au projet étudié. Une plateforme expérimentale a été réalisée pour valider notre approche. / The definition and use of a model coupling product design and project management in the earliest phase of the study of a system correspond to a keen industrial demand. This model allows simultaneous to take into account decisions resulting from the two environments (product and project) but it represents a consequent increase of the search space dimension for the decision-making system, in particular when it concerns a multiobjective optimization. Metaheuristics methods such as evolutionary algorithm are an interesting way to solve this strongly combinative problem. Nevertheless, this problem presents an interesting and unexploited characteristic: It is indeed current to re-use, by adapting them, the components or the procedures previously implemented in pasted product or project. The idea proposed in this work consists in using this “a priori” knowledge available in order to guide the search for new solutions by the evolutionary algorithm. Bayesian network was retained for the interactive modeling of expert knowledge. New evolutionary operators were defined in order to use knowledge contained in the network. Moreover, the system is completed by a process of parametric learning during optimization witch make it possible to adapt the model if guidance does not give good results. The method suggested ensures both a faster and effective optimization, but it also makes it possible to provide to the decision maker a graphic and interactive model of knowledge linked to studied project. An experimental platform was carried out to validate our approach.
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Le sérieux et le manifeste en droit judiciaire privé : contribution à une étude de la certitude en droit / Serious argument and obviousness of the case in procedural law

Callet, Clovis 04 December 2015 (has links)
Le moyen sérieux et l’appréciation manifeste sont des notions bien connues des processualistes qui suscitent toujours la défiance et la circonspection. Elles connaissent pourtant un succès législatif spectaculaire et interviennent dans l’application d’un grand nombre de textes dont l’importance pratique et juridique n’est plus à démontrer. Encore considérées comme la clé la plus insaisissable des dispositifs dans lesquelles elles sont intégrées, ces notions appellent une étude synthétique. Faisant le lien entre des analyses doctrinales éparses qui ne s’intéressent à ces notions qu’au sein d’une procédure identifiée, la thèse tente d’en dégager une définition généralement et globalement opérante. Un examen attentif de la jurisprudence conduit à rejeter la définition classique fondée sur l’évidence et à lui substituer une définition fondée sur le concept plus large de certitude.La réflexion glisse alors imperceptiblement vers la théorie du droit et se tourne vers la question de la vérité en droit. Une connaissance objective des règles de droit est-elle possible ?A la recherche d’une définition succède naturellement une recherche des fonctions des notions. Véritables facteurs de rationalisation du droit processuel, elles y occupent une place essentielle. En dégageant les fonctions pratiques et juridiques des notions, la thèse est amenée à sortir des hypothèses consacrées et à rechercher si les conditions du recours à ces notions ne sont pas déjà réunies dans des dispositifs où il n’y est pourtant pas expressément fait référence. Elle quitte même le terrain du droit positif pour interroger la rationalité des mécanismes dont la mise en œuvre dépend des notions étudiées / An increasing number of statutes relies on the concepts of serious argument and obvious evaluation for their application. Yet no satisfying definition of these concepts has still been found. For if it is usually assumed that these concepts depend on the obviousness of the Law and of the disputed facts, a careful examination of the case law shows well enough that this view is false : one often judges an evaluation obvious only after having demonstrated its truth through a complex argumentation and a long reasoning.Thus, the thesis argues that the concepts refer not to the obviousness of the Law and the disputed events but to the certainty of these. Here the Law refers to a question of jurisprudence : is the case easy or hard ? This new definition leads to the discussion of skepticism regarding the Law. Once a definition that fits the case law has been built, it is necessary to identify the reasons, both legal and pratical, for the use of the concepts in procedural law.From this it becomes possible to a build critical look on the statutes that use the concepts of serious argument and obvious evaluation for their application : is this use justified or should the statutes be changed ? It will also be possible to consider that the appplication of statutes that do not refer to these concepts actually depends on them, or at least should depend on them
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La mise en place d’un droit de la concurrence harmonisé en Afrique et ses mécanismes de mise en œuvre. / the establishment of a harmonized competition law in Africa and its implementation mechanisms of

Vilon-Guezo, Neeskens Christian 01 April 2016 (has links)
Dans un contexte de surabondance d’Organisations d’Intégrations Régionales induisant une pluralité de législations communautaires sur le droit de la concurrence,nous pouvons aisément constater qu’un même Etat appartient à différentes Organisations régionales.Dans ce cadre, lorsqu’il y a un contentieux sur la concurrence, ce foisonnement législatif communautaire engendrera de sérieux conflits de compétences et de risque de recoupement de ces différentes normes.S’il est une évidence que le droit de la concurrence est un instrument juridique impératif dans tout processus d’intégration, il n’en demeure pas aussi moins que la garantie de promotion et de sécurisation de l’investissement en est primordiale.Les solutions que nous avons proposées pour concilier l’application simultanée et sans heurts des différentes normes communautaires existantes sur le droit de la concurrence tout en garantissant une sécurité juridique et judiciaire aux entreprises sont nombreuses.C’est dire que l’étude met un accent sur l’adoption d’une norme harmonisée en Afrique afin de mettre en place une politique de la concurrence saine et crédible qui prendrait en compte d’une part les intérêts des différents acteurs économiques et d’autre part des consommateurs.Ainsi nous parviendrons à un véritable instrument juridique d’ouverture économique qui faciliterait l’accès des marchés africains. / In a context of overabundance of regional organisation of Integration leading toseveral community legislations on the competition law, we can easily notice that thesame states belong to these different organisations.Within this framework, when there is litigation about the competition, thiscommunity legislative abundance will lead to serious conflicts of competences andreinterruption risks of these different norms.If it is an abvious fact that, the competition law is an imperative legal instrument inevery integration process, it is not less important that the safeguard of promotion andreassurance of investment is vital.The solution we suggested to reconcile the smoothly simultaneous application of thedifferent community norms existing on the competition law by safeguarding a legaland judicial security to the companies are many.That is, the study emphasizes on the adoption of an harmonized norm inAfrica in order to put in place a politic of a safe and credible competition that willstake into account on the one hand the interests of the different economic actors andon the other hand of the consumers.In this way, we will reach a real legal instrument of economic aperture that will enable the access to African markets.
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Intégration des contraintes d’industrialisation des pièces en matériaux composites pour l’aide à la décision en conception préliminaire appliquée au procédé RTM

Mouton, Serge 21 May 2010 (has links)
L’intégration des contraintes d’industrialisation, des pièces en matériaux composites, en conception préliminaire, est un enjeu majeur de la compétitivité des entreprises, et s’inscrit dans une démarche de développement durable. Un travail de captation et de mise en forme de la connaissance industrielle a permis de développer une stratégie d’optimisation. Cette stratégie repose sur une approche multi-métiers, elle permet d’estimer la performance technique et économique d’une solution d’industrialisation. L’estimation de la performance est basée sur l’évaluation, pour chaque solution d’industrialisation, du risque de rupture du composant assemblé, du niveau d’intégration fonctionnelle et du coût de fabrication. La définition de la meilleure alternative est obtenue par la comparaison de la performance de solutions et s’appuie sur des méthodes et outils d’aide à la décision. Le risque de rupture est estimé à partir des écarts entre des caractéristiques de la pièce fabriquée par procédé Resin Transfer Molding (RTM) et les caractéristiques nominales. Les caractéristiques de la pièce fabriquée prises en compte sont : - les écarts géométriques, - les écarts de caractéristiques mécaniques. Dans l’industrie aéronautique, certaines pièces de structure en matériaux composites sont réalisées par le procédé RTM. Dans ce type de mise en forme, les caractéristiques mécaniques du composant sont directement liées au niveau d’imprégnation de la préforme. Dans le travail de thèse, les défauts d’imprégnation sont identifiés comme des écarts volumiques d’imprégnation. Ces écarts ont pour conséquence d’altérer les propriétés mécaniques du matériau qui constitue la pièce. L’estimation des écarts volumiques d’imprégnation est obtenue à partir de l’analyse des résultats de la simulation par éléments finis de l’écoulement de résine dans le renfort fibreux (logiciel Pam RTM®). La géométrie de la pièce obtenue par procédé RTM diffère de la géométrie nominale, cet écart est due en partie aux différences entre les caractéristiques physiques des constituants du matériau composite. Les variations géométriques de la pièce fabriquée sont identifiées comme des écarts géométriques de fabrication. Les écarts géométriques sont compensés, lors de la phase d’assemblage, par des déformations garantissant les contacts avec les pièces adjacentes. Ces déformations génèrent un état de contraintes mécaniques au sein de la pièce. La quantification de l’état de contraintes mécaniques est obtenue à partir d’une simulation thermomécanique par éléments finis réalisée par le logiciel Samcef®. L’aide à la décision est basée sur l’étude combinée de l’état de contraintes mécaniques due à la compensation des écarts géométriques et de l’incidence des écarts volumiques d’imprégnation sur les propriétés mécaniques de la pièce. Trois critères permettent d’estimer le risque de rupture du composant assemblé : un critère de rupture des matériaux composites quantifie le risque de rupture, les deux autres critères, prenant en compte les défauts d’imprégnation, majorent le risque de rupture. Afin de faciliter l’interprétation des résultats et la phase de comparaison de solutions, le risque de rupture est présenté sous forme d’une cartographie. En fonction des couplages des valeurs des critères, une optimisation de la conception et/ou de l’industrialisation est proposée. Une évaluation du niveau d’intégration fonctionnelle ainsi que du coût de fabrication complète la démarche d’aide à la décision. / Integrating industrialization constraints of composite materials into preliminary design is a major challenge for companies in terms of competitiveness, and is part of a sustainable development approach. Work on capturing and formatting industry knowledge has helped develop a design optimization strategy. This strategy is based on multidisciplinary rules, and estimates the technical and economic performance of an industrialization solution. This estimate is based on the evaluation of failure risk of component assembly, level of functional integration and manufacturing cost. The definition of the best alternative is obtained by comparing solution performances, relying on decision support methods and tools. The failure risk is estimated from differences between the characteristics of the part manufactured by Resin Transfer Molding Process (RTM) and the nominal part (CAD). The following characteristics of the manufactured part are taken into account: ? - geometric deviations, ? - characteristic mechanical deviations. In the aviation industry, some structural composite parts are manufacture by RTM. In this type of manufacture, the mechanical properties of the component are directly related to the level of preform impregnation. In this thesis, the impregnation defects are identified as volumic impregnation deviations. These deviations have the effect of altering the mechanical properties of material. Estimated volume impregnation deviations are obtained by analysing the results of the finite element simulation of resin flow into the fibrous reinforcement (software Pam RTM ®). The part geometry obtained using the RTM process differs from the nominal geometry, with the deviation due partly to differences between the physical components of the composite material. The geometric variations in the manufactured part are identified as geometric manufacturing deviations. These geometric deviations are offset, in the assembly phase, by deformations due to contact with adjacent parts, which generate a state of mechanical stress within the part. The mechanical stress state is quantified from a finite element thermomechanical simulation carried out using the Samcef ® software. Decision support is based on the combined study of the state of mechanical stress due to the compensation of geometric deviations and the incidence of volume impregnation deviations on the mechanical properties of the part. Three criteria are used to estimate the failure risk of the assembled component: a composite materials failure criterion quantifies failure risk; the other two criteria, taking into account the impregnation defects, increase the failure risk. To facilitate interpretation of results and the solution comparison phase, the failure risk is represented by mapping. Depending on the coupling values of the criteria, optimizing the design and/or industrialization is proposed. An evaluation of the level of functional integration and manufacturing cost complete the decision support process.

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