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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.
141

Ordem pública processual: técnica de controle da regularidade do processo civil / Procedural public policy: regularity control technique of civil procedure

Trícia Navarro Xavier Cabral 23 May 2014 (has links)
O processo civil precisa de ordem, simplicidade e eficiência para atingir o seu escopo de prestação de uma tutela jurisdicional adequada, justa e célere. Para tanto, o ordenamento processual tem sofrido relevantes modificações com o objetivo de se adaptar às novas exigências sociais e jurídicas, em que o formalismo deve servir para proteger, e não para derrubar. Além disso, variadas técnicas processuais têm sido utilizadas para conferir mais efetividade à tutela jurisdicional, sem prejuízo da necessária segurança jurídica. Nesse contexto se insere a ordem pública processual, que embora possa ter uma interessante abordagem principiológica, atua no processo como técnica de controle da regularidade de atos e do procedimento. Por sua vez, o papel do magistrado na gestão dessa técnica se mostra fundamental para ela atinja seu objetivo, que é eliminar do processo os defeitos capazes de macular a sua integridade, bem como a legitimidade da tutela judicial. O controle adequado e tempestivo da regularidade dos atos e do procedimento é um dever do juiz e também uma garantia das partes. Dessa forma, a tese busca identificar as questões processuais passíveis de controle, de acordo com o grau de interesse público que cada uma revela, sendo certo que a lei, a doutrina e a jurisprudência servem de fonte e ainda podem modular a relevância da matéria conforme tempo e espaço em que se observam. Por sua vez, a importância da avaliação do interesse público de cada questão processual reflete no regime jurídico que será estabelecido e as consequências que se estabelecem para os eventuais defeitos com base nas particularidades do caso concreto. Ademais, identificada a irregularidade, o processo civil oferece variadas técnicas de superação, convalidação e flexibilização do vício antes de se declarar a nulidade de atos processuais ou de se inadmitir o procedimento adotado pela parte, numa forma de preservar ao máximo o processo. Já no âmbito recursal, embora haja requisitos específicos de admissibilidade, os vícios detectados em primeiro grau de jurisdição perdem força em segundo grau e perante os Tribunais Superiores, haja vista a necessidade casa vez maior de se proporcionar ao jurisdicionado a entrega da prestação jurisdicional completa, ou seja, com o exame do mérito. Registre-se, ainda, a possibilidade de controle judicial nos meios alternativos de resolução de conflitos, uma vez que também devem se submeter a certos requisitos, para que sejam chancelados e legitimados. Como se observa, a abrangência do tema da ordem pública processual faz com que o ele seja extenso e complexo, o que normalmente assusta os operadores do direito. Portanto, o intento deste estudo é não só descrever o assunto, mas também adotar uma linguagem diferenciada, proporcionando uma nova forma de abordar e sistematizar o que ainda parece ser um dogma em nosso sistema processual. / Civil procedure requires order, simplicity, and efficiency in order to attain its scope of providing adequate jurisdictional adjudication that is fair and expeditious. To do so, the procedural system has endured relevant modifications in furtherance of adapting itself to new social and legal requirements, in which formalism should serve to protect and not to overturn. Furthermore, various technical procedures have been used to grant more effectiveness to jurisdictional adjudication, without damage to necessary juridical certainty. In this context, is contained the procedural public policy, which might possess an interesting approach for the principle, that engages the procedure as a technical means to control the regularity of the acts and the proceedings. In turn, the role of the magistrate in the management of this technique shows itself to be essential in order for it to accomplish its objective, which is to eliminate from the procedure, the defects capable of blotting its integrity, as well as the legitimacy of judicial adjudication. Appropriate and timely control of the regularity of the acts and the proceedings is a duty of the judge and also a guaranty to the parties. In this sense, the thesis seeks to identify procedural issues that could be controlled according to the degree of public interest wherein each one is revealed, being certain that the law, doctrine, and jurisprudence are the source and can still modulate the relevant matter according to the time and space in which they are observed, contextualized, or inserted. In turn, the importance of evaluating the public interest of each procedural matter reflects the legal regime to be established and the consequences established for any eventual defects on the basis of the particulars of the recorded case. Additionally, in identifying the irregularity, civil procedure offers various techniques for overcoming, confirming, and easing of a defect before declaring the nullity of the procedural acts or the inadmissibility of the procedure adopted by the party, in a way to preserve most of the procedure. Already in the appellate context, although there are specific requirements of admissibility, the defects detected at the first level of jurisdiction lose strength at the second level and before the Superior courts, giving each time a greater need to provide jurisdiction and the delivery of full jurisdictional performance, that is, with an examination on the merits. Registering still, the possibility of judicial control as an alternative means of dispute resolution, it also must undergo certain requirements, so as to be approved and legitimized. As noted, the range of the theme of procedural public policy causes it to be extensive and complex, which usually alarms jurists. Therefore, the intent of this study will not only be to describe the subject, but also to adopt a differentiated language, providing a new way to approach and systematize what still seems to be dogma in our procedural system.
142

Ordem pública processual: técnica de controle da regularidade do processo civil / Procedural public policy: regularity control technique of civil procedure

Trícia Navarro Xavier Cabral 23 May 2014 (has links)
O processo civil precisa de ordem, simplicidade e eficiência para atingir o seu escopo de prestação de uma tutela jurisdicional adequada, justa e célere. Para tanto, o ordenamento processual tem sofrido relevantes modificações com o objetivo de se adaptar às novas exigências sociais e jurídicas, em que o formalismo deve servir para proteger, e não para derrubar. Além disso, variadas técnicas processuais têm sido utilizadas para conferir mais efetividade à tutela jurisdicional, sem prejuízo da necessária segurança jurídica. Nesse contexto se insere a ordem pública processual, que embora possa ter uma interessante abordagem principiológica, atua no processo como técnica de controle da regularidade de atos e do procedimento. Por sua vez, o papel do magistrado na gestão dessa técnica se mostra fundamental para ela atinja seu objetivo, que é eliminar do processo os defeitos capazes de macular a sua integridade, bem como a legitimidade da tutela judicial. O controle adequado e tempestivo da regularidade dos atos e do procedimento é um dever do juiz e também uma garantia das partes. Dessa forma, a tese busca identificar as questões processuais passíveis de controle, de acordo com o grau de interesse público que cada uma revela, sendo certo que a lei, a doutrina e a jurisprudência servem de fonte e ainda podem modular a relevância da matéria conforme tempo e espaço em que se observam. Por sua vez, a importância da avaliação do interesse público de cada questão processual reflete no regime jurídico que será estabelecido e as consequências que se estabelecem para os eventuais defeitos com base nas particularidades do caso concreto. Ademais, identificada a irregularidade, o processo civil oferece variadas técnicas de superação, convalidação e flexibilização do vício antes de se declarar a nulidade de atos processuais ou de se inadmitir o procedimento adotado pela parte, numa forma de preservar ao máximo o processo. Já no âmbito recursal, embora haja requisitos específicos de admissibilidade, os vícios detectados em primeiro grau de jurisdição perdem força em segundo grau e perante os Tribunais Superiores, haja vista a necessidade casa vez maior de se proporcionar ao jurisdicionado a entrega da prestação jurisdicional completa, ou seja, com o exame do mérito. Registre-se, ainda, a possibilidade de controle judicial nos meios alternativos de resolução de conflitos, uma vez que também devem se submeter a certos requisitos, para que sejam chancelados e legitimados. Como se observa, a abrangência do tema da ordem pública processual faz com que o ele seja extenso e complexo, o que normalmente assusta os operadores do direito. Portanto, o intento deste estudo é não só descrever o assunto, mas também adotar uma linguagem diferenciada, proporcionando uma nova forma de abordar e sistematizar o que ainda parece ser um dogma em nosso sistema processual. / Civil procedure requires order, simplicity, and efficiency in order to attain its scope of providing adequate jurisdictional adjudication that is fair and expeditious. To do so, the procedural system has endured relevant modifications in furtherance of adapting itself to new social and legal requirements, in which formalism should serve to protect and not to overturn. Furthermore, various technical procedures have been used to grant more effectiveness to jurisdictional adjudication, without damage to necessary juridical certainty. In this context, is contained the procedural public policy, which might possess an interesting approach for the principle, that engages the procedure as a technical means to control the regularity of the acts and the proceedings. In turn, the role of the magistrate in the management of this technique shows itself to be essential in order for it to accomplish its objective, which is to eliminate from the procedure, the defects capable of blotting its integrity, as well as the legitimacy of judicial adjudication. Appropriate and timely control of the regularity of the acts and the proceedings is a duty of the judge and also a guaranty to the parties. In this sense, the thesis seeks to identify procedural issues that could be controlled according to the degree of public interest wherein each one is revealed, being certain that the law, doctrine, and jurisprudence are the source and can still modulate the relevant matter according to the time and space in which they are observed, contextualized, or inserted. In turn, the importance of evaluating the public interest of each procedural matter reflects the legal regime to be established and the consequences established for any eventual defects on the basis of the particulars of the recorded case. Additionally, in identifying the irregularity, civil procedure offers various techniques for overcoming, confirming, and easing of a defect before declaring the nullity of the procedural acts or the inadmissibility of the procedure adopted by the party, in a way to preserve most of the procedure. Already in the appellate context, although there are specific requirements of admissibility, the defects detected at the first level of jurisdiction lose strength at the second level and before the Superior courts, giving each time a greater need to provide jurisdiction and the delivery of full jurisdictional performance, that is, with an examination on the merits. Registering still, the possibility of judicial control as an alternative means of dispute resolution, it also must undergo certain requirements, so as to be approved and legitimized. As noted, the range of the theme of procedural public policy causes it to be extensive and complex, which usually alarms jurists. Therefore, the intent of this study will not only be to describe the subject, but also to adopt a differentiated language, providing a new way to approach and systematize what still seems to be dogma in our procedural system.
143

Fluido micropolar: existência e unicidade de solução forte.

REA, Omar Stevenson Guzman 19 February 2016 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-04-11T18:59:11Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertaçãoOmar.pdf: 629619 bytes, checksum: f018416fe978f2e27de6abfe2542c60c (MD5) / Made available in DSpace on 2017-04-11T18:59:11Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertaçãoOmar.pdf: 629619 bytes, checksum: f018416fe978f2e27de6abfe2542c60c (MD5) Previous issue date: 2016-02-19 / CNPQ / Estudamos aspectos teóricos de um sistema que modela o comportamento dos unidos micro polares incompressíveis num domínio limitado _ Rn (n = 2 ou 3). Especificamente, utilizamos o método espectral de Galerkin para mostrar a existência de soluções fortes e com determinadas condições mostramos a unicidade das soluções / We study theoretical aspects of a system that models the behavior of incompressible micropolar uids in a bounded domain _ Rn (n = 2 or 3). Speci cally, we use the spectral Galerkin method to show the existence of strong solutions and under certain conditions show the uniqueness of solutions.
144

A vontade de verdade como vontade de potência - uma perspectiva discursiva sobre a moralidade / The will of truth as will to power – a discoursive perspective about morality

Silva, Anderson Nowogrodzki da 15 February 1993 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-03-31T17:34:14Z No. of bitstreams: 2 Dissertação - Anderson Nowogrodzki da Silva - 2017.pdf: 1741114 bytes, checksum: 6304ba9926289ff4eccc6751865e247c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: Érika, dê uma olhada na data da defesa e publica~]ao, pois colocou 1993 e no trabalho só identifiquei que foi publicado em 2017 . Com relação a defesa não achei a data na ata. on 2017-04-03T12:00:59Z (GMT) / Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-04-05T17:53:57Z No. of bitstreams: 2 Dissertação - Anderson Nowogrodzki da Silva - 2017.pdf: 1741114 bytes, checksum: 6304ba9926289ff4eccc6751865e247c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: A data de publicação está errada, é 2017. on 2017-04-06T11:12:09Z (GMT) / Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-04-06T17:50:47Z No. of bitstreams: 2 Dissertação - Anderson Nowogrodzki da Silva - 2017.pdf: 1741114 bytes, checksum: 6304ba9926289ff4eccc6751865e247c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: Verifique no formulário de metadados a data da defesa, pois você colocou 1993,na ata está 2017 e na dissertação a data de publicação, também, é 2017. Outro erro (MeStrado em Letras e Linguística) on 2017-04-07T11:06:03Z (GMT) / Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-04-07T17:51:37Z No. of bitstreams: 2 Dissertação - Anderson Nowogrodzki da Silva - 2017.pdf: 1741114 bytes, checksum: 6304ba9926289ff4eccc6751865e247c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: Na ata consta a data de defesa 2017 e na dissertação também está 2017. on 2017-04-10T11:20:37Z (GMT) / Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-04-17T17:21:44Z No. of bitstreams: 2 Dissertação - Anderson Nowogrodzki da Silva - 2017.pdf: 1741114 bytes, checksum: 6304ba9926289ff4eccc6751865e247c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-04-18T15:45:39Z (GMT) No. of bitstreams: 2 Dissertação - Anderson Nowogrodzki da Silva - 2017.pdf: 1741114 bytes, checksum: 6304ba9926289ff4eccc6751865e247c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-18T15:45:39Z (GMT). No. of bitstreams: 2 Dissertação - Anderson Nowogrodzki da Silva - 2017.pdf: 1741114 bytes, checksum: 6304ba9926289ff4eccc6751865e247c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 1993-02-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The present work is the result of some observations about the relations between power and knowledge, the regularities and the possibilities of resistance. We decided, then, think and discuss the articulation between the concepts of Will of Truth and Will to Power, in order to understand the way moral establishes itself in the set of interactions. We demonstrates, like that, the way the society commands itself based on the current knowledge and, at the same time, creates resistences, transforming itself through the confrontation of forces, of the logical of power. Then, the theorical-methodological postulate with wich one works is the study of the discourse by the Foucault’s archaeogenealogy, bringing also, to the research, Nietzsche’s notions and reflections, in order to better illustrate the way society is constituted and your ways to see and say. The use of this theoretical contribution is justified because it is based on numerous unfoldings and contributions to the studies of the language in a historicist perspective. Thereby, it seeks to highlight issues pertinent to this field of study; What means Will to Power? What means Will of Truth? How those concepts relate on na enviroment were resistence and regularity coexist? What are the consequences that these concepts can have in what we propose to investigate? How do you set up a moral control mechanism? Those are questions that guide this work and that tend to worry for a more accurate theoretical analysis. Another aspect that is relevant to this approach is the understanding of the concept of device; according Courtine (2013), we should look to the device as a set of knowledges that can be crossed and make others appear, having a strategic function regulated by the power relations. Foucault and Nietzsche provide a basis for reading the concepts that are discussed, being complemented by your readers. This study is qualitative in that we do not look for exhaustive but representative data. Therefore, will be described, related and crossed statements that present in the contemporaneousness the quest to control morally the body, observing the resumption of the “already said” in function of legitimizing the discourses, leading to the discussion of why a person who goes hungry do not steal to eat as an example of the dynamics of morality. Finally, we can infer that the subject of discourse, although situated sociohistorically in capitalist societies, that reinforce the morality control, can resist which leads to the continuous transformation. / O presente trabalho é fruto de algumas observações sobre as relações de poder e saber, as regularidades e as possibilidades de resistência. Decidiu-se, então, pensar e discutir a articulação entre os conceitos de Vontade de Verdade e Vontade de Potência, a fim de entender o modo como a moral se instaura no conjunto das interações. Demonstra-se, assim, o modo como a sociedade se ordena com base na atualidade do saber e, ao mesmo tempo, cria resistências, transformando-se por meio do enfrentamento de forças, da lógica da potência. Então, o postulado teórico-metodológico com o qual se trabalha é o estudo do discurso por meio da arqueogenealogia de Foucault, trazendo, ainda, para a pesquisa, as noções e reflexões de Nietzsche, a fim de melhor ilustrar o modo como se constitui a sociedade, seus modos de ver e dizer. Justifica-se o uso desse aporte teórico por se basear em inúmeros desdobramentos e contribuições para os estudos da linguagem em uma perspectiva historicista. Com isso, busca-se evidenciar questões pertinentes a esse campo de estudo; O que significa Vontade de Potência? O que significa Vontade de Verdade? Como esses conceitos se relacionam num ambiente em que coexistem a resistência e a regularidade? Quais os desdobramentos que esses conceitos podem ter no que se propõe investigar? Como se configura um mecanismo de controle moral? São questões que norteiam este trabalho e que tendem a inquietar para uma análise teórica mais apurada. Outro aspecto que se torna relevante à abordagem é um entendimento sobre o conceito de dispositivo; segundo Courtine (2013), deve-se olhar para o dispositivo como um conjunto de saberes que se entrecruzam e fazem aparecer outros, possuindo uma função estratégica regulada pelas relações de poder. Foucault e Nietzsche constituem a base de leituras dos conceitos que serão abordados, sendo complementados por seus leitores. Essa apreciação é de cunho qualitativo, em que não se buscam dados exaustivos, mas representativos. Assim, serão descritos, relacionados e entrecruzados enunciados, que apresentem, na contemporaneidade, a busca por controlar moralmente o corpo, observando a retomada do “já dito”, em função de legitimar os discursos, levando à discussão do motivo pelo qual uma pessoa que passa fome não rouba para se alimentar, como um exemplo da dinâmica da moralidade. Enfim, podemos inferir que o sujeito do discurso, ainda que situado sociohistoricamente em sociedades capitalistas, que reforçam o controle da moral, pode resistir, o que leva à transformação contínua.
145

Forcing e regularidade na reta real / Forcing and regularity in the real line

Michel Fernandes Gaspar 05 March 2018 (has links)
O estudo das propriedades de regularidade na reta real é tão antigo quanto o surgimento da teoria dos conjuntos no final do século XIX. Essas propriedades indicam bom comportamento para subconjuntos da reta real, sendo os exemplos mais proeminentes a propriedade do conjunto perfeito, a Lebesgue mensurabilidade e a Baire mensurabilidade. Neste trabalho outras propriedades de regularidade são exploradas, como a propriedade de Ramsey, a propriedade doughnut, a Marczewski mensurabilidade, a Miller mensurabilidade, a Laver mensurabilidade, dentre outras. A relação que existe entre propriedades de regularidade e forcing é conhecida desde a década de 70 com os trabalhos de Robert Solovay, que, por exemplo, construiu um modelo de teoria dos conjuntos onde todo subconjunto da reta real é Lebesgue mensurável, Baire mensurável e tem a propriedade do conjunto perfeito. Todas essas propriedades de regularidade são capturadas em uma definição geral recorrendo à poderosa técnica do \\textit{forcing idealizado}, introduzida e explorada por Jindrich Zapletal em 2004. O principal estudo sistemático das propriedades de regularidade via forcing idealizado foi feito por Yurii Khomskii em 2012 em sua tese de doutorado. O resultado de Solovay mencionado acima é provado nesse contexto geral de regularidade. Também são exploradas caracterizações para a regularidade dos conjuntos no segundo nível da hierarquia projetiva via forcing sobre L. Para a maioria dos assuntos abordados é dada alguma nota histórica. / The study of the regularity properties in the real line is as old as the beginning of set theory at the end of the 19th century. These properties indicate well behavior for subsets of the real line, being the Lebesgue measurability, Baire measurability and perfect set properties the most prominent examples. In this work other regularity properties are explored, such as the Ramsey property, the doughnut property, the Marczewski measurability, the Miller measurability, the Laver measurability, among others. The relationship between regularity properties and forcing is known since the 70\'s with the work of Robert Solovay, who, for example, constructed a model of set theory in which every subset of the real line is Lebesgue measurable, Baire measurable, and has the perfect set property. All of theses regularity properties are captured by a general definition making use of the powerful technique of \\textit, introduced by Jindrich Zapletal in 2008. The main systematic study of regularity properties via idealized forcing was done by Yurii Khomskii in 2012 in his Ph.D dissertation. The result of Solovay mentioned above is proved in this general framework. Characterization results for regularity properties of the sets in the second level of the projective hierarchy via forcing over L are also explored. Some historical notes are provided for most of the addressed subjects.
146

Méthodes de résolution d’inclusions variationnelles sous hypothèses de stabilité / Methods for solving variational inclusions under stability assumptions

Burnet, Steeve 30 October 2012 (has links)
Dans cette thèse, nous nous intéressons à des inclusions de la forme 0∈ f( x) + F(x), où f est une application univoque et F est une application multivoque à graphe fermé. Ces dernières années, diverses méthodes de résolutions d'inclusions de ce type ont été développées par les chercheurs et, après un bref rappel sur quelques notions d'analyse (univoque et multivoque) nous en présentons quelques unes utilisant l'hypothèse de régularité métrique sur l'application multivoque. Dans la suite de notre travail, plutôt que d'utiliser cette hypothèse de régularité métrique, nous lui préférons des hypothèses directement liées à la solution qui sont la semistabilité et l'hemistabilité. Notons que la semistabilité d'une solution x̅ de l'inclusion 0∈G(x) est en fait équivalente à la sous-régularité métrique forte de l'application multivoque G en x̅ pour 0. Après avoir présenté des méthodes utilisant la semistabilité et l'hemistabilité, nous exposons les nouveaux résultats auxquels nous avons abouti qui consistent essentiellement en des améliorations des méthodes présentées. Ce que nous entendons par améliorations se décline en deux points principaux : soit nous obtenons un meilleur taux de convergence, soit nous utilisons des hypothèses plus faibles qui nous permettent d'obtenir des taux de convergence similaires. / In this thesis, we focus on inclusions in the form of 0∈ f( x) + F(x), where f is a single-valued function and F is a set-valued map with closed graph. In the last few years, various methods to solve such inclusions have been developed; after having recalled some notions in analysis (single-valued and set-valued) we present some of them using metric regularity on the set-valued map. Then, instead of considering this metric regularity assumption, we prefer assumptions which are directly connected to the solution, that are semistability and hemistability. One can note that semistabily of a solution x̅ of the inclusion 0∈G(x) is actually equivalent strong metric subregularity on the set-valued map G at x̅ for 0. After having presented some methods using semistability and hemistability, we show the new results we obtained, most of them being improvement of the presented methods. What we mean by improvement is mainly a better convergence rate on the one hand, and weaker assumptions that lead to similar convergence rate, on the other.
147

Régularité fine de processus stochastiques et analyse 2-microlocale / Fine regularity of stochastic processes and 2-microlocal analysis

Balança, Paul 06 February 2014 (has links)
Les travaux présentés dans cette thèse s'intéressent à la géométrie fractale de processus stochastiques à travers le prisme d'un outil appelé l'analyse 2-microlocale. Ce dernier est issu d'une autre branche des mathématiques, l'analyse fonctionnelle et l'étude des équations aux dérivées partielles, et s'est avéré être pertinent pour décrire la géométrie fine de fonctions déterministes ou de processus aléatoires, généralisant notamment les exposants de Hölder classiques. Nous envisageons ainsi dans ce manuscrit différentes classes de processus, traitant en premier lieu le cas des martingales continues et de l'intégrale stochastique d'Ito. La régularité 2-microlocale de ces derniers fait notamment apparaître un autre concept, la pseudo frontière 2-microlocale, étroitement lié à son aîné. Nous appliquons également ce formalisme d'étude à une classe de processus gaussiens : le mouvement brownien multifractionnaire. Nous caractérisons ainsi sa régularité 2-microlocale et hölderienne, et déterminons dans un deuxième temps la forme générale de la dimension fractale de ses trajectoires. Dans notre étude portant sur les processus de Lévy, nous combinons le formalisme 2-microlocale à l'analyse multifractale, permettant alors de mettre en évidence des comportements géométriques n'étant pas captés par les outils usuels. Nous obtenons également en corollaire le spectre multifractal des processus fractionnaires de Lévy. Enfin, dans une dernière partie, nous nous intéressons à la définition et aux propriétés de certains processus de Markov multiparamètres, pouvant être plus généralement indicés par des ensembles. / The work presented in this thesis concerns the study of the fractal geometry of stochastic processes using the formalism of 2-microlocal analysis. The latter has been introduced in another branch of mathematics -functional analysis- but has also proved to be relevant to describe the geometry of deterministic functions or random processes, extending in particular the classic Hölder exponents. Several classes of processes are investigated in this manuscript, beginning with continuous martingales and Ito integrals. In particular, the characterisation of the 2-microlocal regularity of the latter leads to the introduction of a closely related concept: the pseudo 2-microlocal frontier. We also investigate using this formalism a class of Gaussian processes called multifractional Brownian motion and obtain a fine description of its Hölder and 2-microlocal behaviours. In addition, we characterize entirely the Hausdorff and Box dimensions of its graph. In our study of Lévy processes, we combine the 2-microlocal formalism and multifractal analysis to describe their regularity, exhibiting in particular some subtle geometrical behaviours which are not captured by classic tools. Furthermore, as a corollary of this result, we also determine the multifractal spectrum of another family of processes: the fractional Lévy processes. Lastly, we also define a class of multiparameter and set-indexed Markov processes and study its properties.
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Cauchy problem for the incompressible Navier-Stokes equation with an external force and Gevrey smoothing effect for the Prandtl equation / Problème de Cauchy pour les équations de Navier-Stokes en présence d'une force extérieure et l'effet régularisant Gevrey de l'équation de Prandtl

Wu, Di 06 November 2017 (has links)
Dans cette thèse on étudie des équations de la mécanique des fluides. On considère deux modèles : les équations de Navier-Stokes équation dans R3 en présence d'une force extérieure, et l'équation de Prandtl dans le demi plan. Pour le système de Navier-Stokes, on s'intéresse à l'existence locale en temps, l'unicité, le comportement global en temps et des critères d'explosion. Pour l'équation de Prandtl dans le demi plan, on s'intéresse à la régularité Gevrey. Le manuscrit est constitué de quatre chapitres. Dans le premier chapitre, on introduit quelques concepts de base sur les équations de la mécanique des fluides et on rappelle le sens physique des deux modèles précédents ainsi que quelques résultats mathématiques. Ensuite on énonce brièvement nos principaux résultats et les motivations. Enfin on mentionne quelques problèmes ouverts. Le second chapitre est consacré au problème de Cauchy pour les équations de Navier-Stokes dans R3 en présence d'une petite force extérieure, peu régulière. On démontre l'existence locale en temps pour ce système pour toute donnée initiale appartenant à un espace de Besov critique avec régularité négative. On obtient de plus trois résultats d'unicité pour ces solutions. Enfin on étudie le comportement en temps grand et la stabilité de solutions a priori globales. Le troisième chapitre traite d'un critère d'explosion pour les équations de Navier-Stokes avec une force extérieure indépendante du temps. On met en place une décomposition en profils pour les équations de Navier-Stokes forcées. Cette décomposition permet de faire un lien entre les équations forcées et non forcées, ce qui permet de traduire une information d'explosion de la solution non forcée vers la solution forcée. Dans le Chapitre 4 on étudie l'effet régularisant Gevrey de la solution locale en temps de l'équation de Prandtl dans le demi plan. Il est bien connu que l'équation de couche limite de Prandtl est instable pour des données initiales générales, et bien posée dans des espaces de Sobolev pour des données initiales monotones. Sous une hypothèse de monotonie de la vitesse tangentielle du flot, on démontre la régularité Gevrey pour la solution de l'équation de Prandtl dans le demi plan pour des données initiales dans un espace de Sobolev. / This thesis deals with equations of fluid dynamics. We consider the following two models: one is the Navier-Stokes equation in R3 with an external force, the other one is the Prandtl equation on the half plane. For the Navier-Stokes system, we focus on the local in time existence, uniqueness, long-time behavior and blowup criterion. For the Prandtl equation on the half-plane, we consider the Gevrey regularity. This thesis consists in four chapters. In the first chapter, we introduce some background on equations of fluid dynamics and recall the physical meaning of the above two models as well as some well-known mathematical results. Next, we state our main results and motivations briefly. At last we mention some open problems. The second chapter is devoted to the Cauchy problem for the Navier-Stokes equation equipped with a small rough external force in R3. We show the local in time existence for this system for any initial data belonging to a critical Besov space with negative regularity. Moreover we obtain three kinds of uniqueness results for the above solutions. Finally, we study the long-time behavior and stability of priori global solutions.The third chapter deals with a blow-up criterion for the Navier-Stokes equation with a time independent external force. We develop a profile decomposition for the forced Navier-Stokes equation. The decomposition enables us to connect the forced and the unforced equations, which provides the blow-up information from the unforced solution to the forced solution. In Chapter 4, we study the Gevrey smoothing effect of the local in time solution to the Prandtl equation in the half plane. It is well-known that the Prandtl boundary layer equation is unstable for general initial data, and is well-posed in Sobolev spaces for monotonic initial data. Under a monotonicity assumption on the tangential velocity of the outflow, we prove Gevrey regularity for the solution to Prandtl equation in the half plane with initial data belonging to some Sobolev space.
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Problémes bien-posés et étude qualitative pour des équations cinétiques et des équations dissipatives. / Well-posedness and qualitative study for some kinetic equations and some dissipative equations

Cao, Hongmei 14 October 2019 (has links)
Dans cette thèse, nous étudions certaines équations différentielles partielles avec mécanisme dissipatif, telles que l'équation de Boltzmann, l'équation de Landau et certains systèmes hyperboliques symétriques avec type de dissipation. L'existence globale de solutions ou les taux de dégradation optimaux des solutions pour ces systèmes sont envisagées dans les espaces de Sobolev ou de Besov. Les propriétés de lissage des solutions sont également étudiées. Dans cette thèse, nous prouvons principalement les quatre suivants résultats, voir les chapitres 3-6 pour plus de détails. Pour le premier résultat, nous étudions le problème de Cauchy pour le non linéaire inhomogène équation de Landau avec des molécules Maxwelliennes (= 0). Voir des résultats connus pour l'équation de Boltzmann et l'équation de Landau, leur existence globale de solutions est principalement prouvée dans certains espaces de Sobolev (pondérés) et nécessite un indice de régularité élevé, voir Guo [62], une série d'oeuvres d'Alexander Morimoto-Ukai-Xu-Yang [5, 6, 7, 9] et des références à ce sujet. Récemment, Duan-Liu-Xu [52] et Morimoto-Sakamoto [145] ont obtenu les résultats de l'existence globale de solutions à l'équation de Boltzmann dans l'espace critique de Besov. Motivés par leurs oeuvres, nous établissons l'existence globale de la solution dans des espaces de Besov spatialement critiques dans le cadre de perturbation. Précisément, si le datum initial est une petite perturbation de la distribution d'équilibre dans l'espace Chemin-Lerner eL 2v (B3=2 2;1 ), alors le problème de Cauchy de Landau admet qu'une solution globale appartient à eL 1t eL 2v (B3=2 2;1 ). Notre résultat améliore le résultat dans [62] et étend le résultat d'existence globale de l'équation de Boltzmann dans [52, 145] à l'équation de Landau. Deuxièmement, nous considérons le problème de Cauchy pour l'équation de Kac non-coupée spatialement inhomogène. Lerner-Morimoto-Pravda-Starov-Xu a considéré l'équation de Kac non-coupée spatialement inhomogène dans les espaces de Sobolev et a montré que le problème de Cauchy pour la fluctuation autour de la distribution maxwellienne admise S 1+ 1 2s 1+ 1 2s Propriétés de régularité Gelfand-Shilov par rapport à la variable de vélocité et propriétés de régularisation G1+ 1 2s Gevrey à la variable de position. Et les auteurs ont supposé qu'il restait encore à déterminer si les indices de régularité 1 + 1 2s étaient nets ou non. Dans cette thèse, si la donnée initiale appartient à l'espace de Besov spatialement critique, nous pouvons prouver que l'équation de Kac inhomogène est bien posée dans un cadre de perturbation. De plus, il est montré que la solution bénéficie des propriétés de régularisation de Gelfand-Shilov en ce qui concerne la variable de vitesse et des propriétés de régularisation de Gevrey en ce qui concerne la variable de position. Dans notre thèse, l'indice de régularité de Gelfand-Shilov est amélioré pour être optimal. Et ce résultat est le premier qui présente un effet de lissage pour l'équation cinétique dans les espaces de Besov. A propos du troisième résultat, nous considérons les équations de Navier-Stokes-Maxwell compressibles apparaissant dans la physique des plasmas, qui est un exemple concret de systèmes composites hyperboliques-paraboliques à dissipation non symétrique. On observe que le problème de Cauchy pour les équations de Navier-Stokes-Maxwell admet le mécanisme dissipatif de type perte de régularité. Par conséquent, une régularité plus élevée est généralement nécessaire pour obtenir le taux de dégradation optimal de L1(R3)-L2(R3) type, en comparaison avec cela pour l'existence globale dans le temps de solutions lisses. / In this thesis, we study some kinetic equations and some partial differential equations with dissipative mechanism, such as Boltzmann equation, Landau equation and some non-symmetric hyperbolic systems with dissipation type. Global existence of solutions or optimal decay rates of solutions for these systems are considered in Sobolev spaces or Besov spaces. Also the smoothing properties of solutions are studied. In this thesis, we mainly prove the following four results, see Chapters 3-6 for more details. For the _rst result, we investigate the Cauchy problem for the inhomogeneous nonlinear Landau equation with Maxwellian molecules ( = 0). See from some known results for Boltzmann equation and Landau equation, their global existence of solutions are mainly proved in some (weighted) Sobolev spaces and require a high regularity index, see Guo [62], a series works of Alexandre-Morimoto-Ukai-Xu-Yang [5, 6, 7, 9] and references therein. Recently, Duan-Liu-Xu [52] and Morimoto-Sakamoto [145] obtained the global existence results of solutions to the Boltzmann equation in critical Besov spaces. Motivated by their works, we establish the global existence of solutions for Landau equation in spatially critical Besov spaces in perturbation framework. Precisely, if the initial datum is a small perturbation of the equilibrium distribution in the Chemin-Lerner space eL 2v (B3=2 2;1 ), then the Cauchy problem of Landau equation admits a global solution belongs to eL 1t eL 2v (B3=2 2;1 ). Our results improve the result in [62] and extend the global existence result for Boltzmann equation in [52, 145] to Landau equation. Secondly, we consider the Cauchy problem for the spatially nhomogeneous non-cuto_ Kac equation. Lerner-Morimoto-Pravda-Starov-Xu [117] considered the spatially inhomogeneous non-cuto_ Kac equation in Sobolev spaces and showed that the Cauchy problem for the uctuation around the Maxwellian distribution admitted S 1+ 1 2s 1+ 1 2s Gelfand-Shilov regularity properties with respect to the velocity variable and G1+ 1 2s Gevrey regularizing properties with respect to the position variable. And the authors conjectured that it remained still open to determine whether the regularity indices 1+ 1 2s is sharp or not. In this thesis, if the initial datum belongs to the spatially critical Besov space eL 2v (B1=2 2;1 ), we prove the well-posedness to the inhomogeneous Kac equation under a perturbation framework. Furthermore, it is shown that the weak solution enjoys S 3s+1 2s(s+1) 3s+1 2s(s+1) Gelfand-Shilov regularizing properties with respect to the velocity variableand G1+ 1 2s Gevrey regularizing properties with respect to the position variable. In our results, the Gelfand-Shilov regularity index is improved to be optimal. And this result is the _rst one that exhibits smoothing e_ect for the kinetic equation in Besov spaces. About the third result, we consider compressible Navier-Stokes-Maxwell equations arising in plasmas physics, which is a concrete example of hyperbolic-parabolic composite systems with non-symmetric dissipation. It is observed that the Cauchy problem for Navier-Stokes-Maxwell equations admits the dissipative mechanism of regularity-loss type. Consequently, extra higher regularity is usually needed to obtain the optimal decay rate of L1(R3)-L2(R3) type, in comparison with that for the global-in-time existence of smooth solutions.
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Courbes et applications optimales à valeurs dans l'espace de Wasserstein / Optimal curves and mappings valued in the Wasserstein space

Lavenant, Hugo 24 May 2019 (has links)
L'espace de Wasserstein est l'ensemble des mesures de probabilité définies sur un domaine fixé et muni de la distance de Wasserstein quadratique. Dans ce travail, nous étudions des problèmes variationnels dans lesquels les inconnues sont des applications à valeurs dans l'espace de Wasserstein.Quand l'espace de départ est un segment, c'est-à-dire quand les inconnues sont des courbes à valeurs dans l'espace de Wasserstein, nous nous intéressons à des modèles où, en plus de l'action des courbes, des termes pénalisant les configurations de congestion sont présents. Nous développons des techniques permettant d'extraire de la régularité à partir de l'interaction entre l'évolution optimale de la densité (minimisation de l'action) et la pénalisation de la congestion, et nous les appliquons à l'étude des jeux à champ moyen et de la formulation variationelle des équations d'Euler.Quand l'espace de départ n'est plus seulement un segment mais un domaine de l'espace euclidien, nous considérons seulement le problème de Dirichlet, c'est-à-dire la minimisation de l'action (qui peut être appelée l'énergie de Dirichlet) parmi toutes les applications dont les valeurs sur le bord du domaine de départ sont fixées. Les solutions sont appelées les applications harmoniques à valeurs dans l'espace de Wasserstein. Nous montrons que les différentes définitions de l'énergie de Dirichlet présentes dans la littérature sont en fait équivalentes; que le problème de Dirichlet est bien posé sous des hypothèses assez faibles; que le principe de superposition est mis en échec lorsque l'espace de départ n'est pas un segment; que l'on peut formuler une sorte de principe du maximum; et nous proposons une méthode numérique pour calculer ces applications harmoniques. / The Wasserstein space is the space of probability measures over a given domain endowed with the quadratic Wasserstein distance. In this work, we study variational problems where the unknowns are mappings valued in the Wasserstein space. When the source space is a segment, i.e. when the unknowns are curves valued in the Wasserstein space, we are interested in models where, in addition to the action of the curves, there are some terms which penalize congested configurations. We develop techniques to extract regularity from the minimizers thanks to the interplay between optimal density evolution (minimization of the action) and penalization of congestion, and we apply them to the study of Mean Field Games and the variational formulation of the Euler equations. When the source space is no longer a segment but a domain of a Euclidean space, we consider only the Dirichlet problem, i.e. the minimization of the action (which can be called the Dirichlet energy) among mappings sharing a fixed value on the boundary of the source space. The solutions are called harmonic mappings valued in the Wasserstein space. We prove that the different definitions of the Dirichlet energy in the literature turn out to be equivalent; that the Dirichlet problem is well-posed under mild assumptions; that the superposition principle fails if the source space is no longer a segment; that a sort of maximum principle holds; and we provide a numerical method to compute these harmonic mappings.

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