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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.
61

Multiplicidade de Soluções para Problemas Elípticos Semilineares Envolvendo o Expoente Crítico de Sobolev

Prazeres, Disson Soares dos 04 August 2010 (has links)
Made available in DSpace on 2015-05-15T11:46:26Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 549935 bytes, checksum: f7562c326b5af177cb80a71a184aa0c9 (MD5) Previous issue date: 2010-08-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this dissertation, we study the multiplicity of solutions for the following class of semilinear elliptic problems involving the critical Sobolev exponent, ---u = - juj2---2 u + f (x; u) ; x 2 e u = 0; x 2 @ ; where N - 3, - RN is a smooth and bounded domain, - is a positive real parameter and 2- = 2N= (N - 2) is the critical Sobolev exponent. In obtaining our result, we use variational methods, such as, minimax theorems, Lusternik-Schnirelman theorems, as well as, concentration-compactness lemma. / Nesta dissertação, estudamos a multiplicidade de soluções para a seguinte classe de problemas elípticos semilineares envolvendo o expoente crítico de Sobolev, --u = - juj2---2 u + f (x; u) ; x 2 e u (x) = 0; x 2 @ ; onde N - 3, - RN é um dominio suave e limitado, - é um parâmetro real positivo e 2* = 2N= (N - 2) é o expoente crítico de Sobolev. Na prova dos resultados, usamos métodos variacionais, tais como, teoremas do tipo minimax, teoremas do tipo Lusternik-Schnirelman, bem como, lemas de concentração-compacidade.
62

Etude de filtres hyperfréquences compacts à basse fréquence / Study of low frequency compact microwave filters

Thépaut, Loïc 08 March 2017 (has links)
Les développements récents des systèmes hyperfréquences conduisent à des contraintes drastiques sur la taille et le coût des composants, et en particulier sur les Filtres Passe-Bande (BPF). L’objectif de cette thèse était d’apporter des solutions innovantes pour du filtrage large-bande compact en basses fréquences. Nous avons proposé deux solutions topologiques de compacité.La première solution est axée sur l’amélioration de la compacité des résonateurs grâce au résonateur multi-sections. Cette topologie a été théorisée et modélisée afin de l’optimiser. La compacité apportée par le résonateur multi-sections a été démontrée à travers la réalisation de filtres interdigité. La deuxième solution est une nouvelle topologie du filtre combline appelée filtre combline à couplage électrique (ECC). Nous avons également montré que ces solutions topologiques sont compatibles avec d’autres solutions technologiques de compacité (multicouche…).Ces solutions permettent de résoudre les problèmes d’encombrement et d’intégration des filtres actuels tout en gardant des performances électriques équivalentes. / Recent developments in microwave systems lead to drastic constraints on the size and cost of components, and in particularly on Passband Filters (BPF). The aim of this thesis was to provide innovative solutions for low band compact broadband filtering. We proposed two topological solutions of compactness.The first solution focuses on improving the compactness of the resonator thanks to the multisections resonator. This topology has been theorized and modeled to optimize it. The compactness provided by the multi-sections resonator has been shown by the realization of interdigital filters. The second solution is a new topology of the combline filter, electrical coupling combline filter (ECC).We have also shown that these topological solutions are compatible with other technological solutions of compactness (multilayer ...).These solutions solve the size and integration problems of current filters with equivalentelectrical performance.
63

Inégalités de type Trudinger-Moser et applications / Trudinger-Moser type inequalities and applications

Zghal, Mohamed Khalil 06 February 2016 (has links)
Cette thèse porte sur quelques inégalités de type Trudinger-Moser et leurs applications à l'étude des injections de Sobolev qu'elles induisent dans les espaces d'Orlicz et à l'analyse d'équations aux dérivées partielles non linéaires à croissance exponentielle.Le travail qu'on présente ici se compose de trois parties. La première partie est consacrée à la description du défaut de compacité de l'injection de Sobolev 4D dans l'espace d'Orlicz dansle cadre radial.L'objectif de la deuxième partie est double. D'abord, on caractérise le défaut de compacité de l'injection de Sobolev 2D dans les différentes classes d'espaces d'Orlicz. Ensuite, on étudiel'équation de Klein-Gordon semi-linéaire avec non linéarité exponentielle, où la norme d'Orlicz joue un rôle crucial. En particulier, on aborde les questions d'existence globale, de complétude asymptotique et d'étude qualitative.Dans la troisième partie, on établit des inégalités optimales de type Adams, en étroite relation avec les inégalités de Hardy, puis on fournit une description du défaut de compacité des injections de Sobolev qu'elles induisent / This thesis focuses on some Trudinger-Moser type inequalities and their applications to the study of Sobolev embeddings they induce into the Orlicz spaces, and the investigation of nonlinear partial differential equations with exponential growth.The work presented here includes three parts. The first part is devoted to the description of the lack of compactness of the 4D Sobolev embedding into the Orlicz space in the radialframework.The aim of the second part is twofold. Firstly, we characterize the lack of compactness of the 2D Sobolev embedding into the different classes of Orlicz spaces. Secondly, we undertakethe study of the nonlinear Klein-Gordon equation with exponential growth, where the Orlicz norm plays a crucial role. In particular, issues of global existence, scattering and qualitativestudy are investigated.In the third part, we establish sharp Adams-type inequalities invoking Hardy inequalities, then we give a description of the lack of compactness of the Sobolev embeddings they induce
64

Intenzivní městský dům / Intensive City House

Murínová, Lenka January 2017 (has links)
The topic of diploma thesis is to design a "city house", in a form of the intensive urban structure, using the area with the greatest efficiency in terms of housing, services and jobs on a relatively small area. The main function of the new complex is housing supplemented by services, as well as, leisure and education facilities. The art school, the gallery, the office space and other facilities serve not only the residents of the "intensive house", but also the rest of the public, with the possibility of getting new jobs at an accessible distance, which is the main task of an intensive structure. The aim is to create a multifunctional urban building that revitalizes the inefficiently used area and at the same time brings green spaces designed for relaxation that are missing in this area.
65

Valorisation des sédiments de dragage dans des matrices polymères / Valoization of dredged sediments in polymer matrix

Ennahal, Ilyas 14 June 2019 (has links)
En France, les volumes de sédiments de dragage générés chaque année pour la maintenance des ports et des voies navigables sont estimés à environ 50 millions de mètres cubes. La gestion de ces sédiments représente un enjeu économique, social et environnemental pour les gestionnaires. Aujourd’hui, l’une des solutions privilégiées est le développement de la gestion à terre de ces matériaux, qui consiste à les réutiliser comme matières premières secondaires en substitution partielle ou totale de matières nobles. De nombreux travaux de recherche ont été effectués sur la problématique de la valorisation des sédiments de dragage et de curage et de nouvelles filières sont actuellement toujours à l’étude (ciments, enrochements pour travaux maritimes et fluviaux, bétons cellulaires, granulats artificiels, etc.). Ce travail de thèse s’inscrit dans un contexte d’économie circulaire et vise à permettre le développement d’une gestion durable et responsable des ressources naturelles non renouvelables. Ceci à travers la réutilisation des sédiments de dragage dans la formulation de matériaux composites traités par des liants thermodurcissables ou thermoplastiques. Ainsi, après un travail de synthèse bibliographique sur les principales propriétés des sédiments de dragage, les méthodes de formulation des mortiers polymères et les modalités d’intégration des matériaux alternatifs dans ces matrices sont été décrites. Les expérimentations portent plus particulièrement sur la formulation de matériaux à partir de polymères thermodurcissables (résines de type Epoxy ou Polyester) et thermoplastiques (plastiques recyclés issus du tri des déchets). La validation des performances techniques des formulations optimisées pour chacun des traitements a été effectuée pour des usages en revêtements de sols ou en granulats légers dans des bétons hydrauliques. Enfin, la dernière partie de la thèse a été consacrée à l’étude de l’acceptabilité environnementale des nouveaux matériaux à travers la réalisation des essais de lixiviation dynamique sur monolithes. Les travaux menés ont permis de démontrer la faisabilité technique et environnementale de la valorisation des sédiments en tant que charge minérale dans des matrices polymères, avec des taux d’incorporation de sédiments significatifs pouvant atteindre jusqu’à 80 %. Ce qui confirme l’intérêt de cette typologie de traitement pour la valorisation des sédiments de dragage. / In France, the volume of dredged sediments generated each year through maintenance of ports and waterways, is estimated at around 50M cubic meters. The management of these sediments represents an economic, social and environmental stake for the managers of the waterways. Today, one of the solution is the onshore management of these sediments, which consists on their reuse as secondary raw materials in partial or total substitution of natural materials for civil engineering applications such as sub-base road materials, embankments, concrete, bricks/tiles, and cement production. In this context this study was initiated in order to define a long-term value chain for dredging sediments for a sustainable and responsible management of natural resources. This through the valorization of dredged sediments in polymer matrix mortar formulations. Indeed, this research presents an innovative solution that preserves natural resources by promoting the use of local resources, such as dredged sediments. In order to achieve this objective, the study included several phases : the first part is devoted to the state of the art concerning dredged sediments, polymer mortars and the recovery of waste in polymer mortars. In the second part, we studied recovery of sediment in thermosetting matrix polymers (Epoxy-Polyester). In the third part we studied the possibilities of incorporating sediments in recycled thermoplastic matrix. The materials from this combination have been used as lightweight aggregates for mortar formulation. Finally, in the last part was devoted to environmental monitoring of new formulated materials. This is done through leaching tests carried out on crushed samples and monoliths, to ensure the environmental safety of these materials. The result obtained with the different formulations tested, show the technical and environmental feasibility of valorization of sediments as mineral filler in polymer mortars, with sediments incorporation rates range between 50 and 80%. Indeed, the use of a polymer matrix makes it possible to have better physico-mechanical and chemical results with cementitious matrix mortars.
66

Pathwise anticipating random periodic solutions of SDEs and SPDEs with linear multiplicative noise

Wu, Yue January 2014 (has links)
In this thesis, we study the existence of pathwise random periodic solutions to both the semilinear stochastic differential equations with linear multiplicative noise and the semilinear stochastic partial differential equations with linear multiplicative noise in a Hilbert space. We identify them as the solutions of coupled forward-backward infinite horizon stochastic integral equations in general cases, and then perform the argument of the relative compactness of Wiener-Sobolev spaces in C([0, T],L2Ω,Rd)) or C([0, T],L2(Ω x O)) and Schauder's fixed point theorem to show the existence of a solution of the coupled stochastic forward-backward infinite horizon integral equations.
67

Tipo arquitetônico em empreendimentos habitacionais de interesse social: impactos ambientais, diferenças no custo e em quesitos de habitabilidade / Architectural type in social housing design: environmental impacts, differences in cost and habitability

Schneck, Eduardo Reuter 15 January 2013 (has links)
Submitted by Maicon Juliano Schmidt (maicons) on 2015-07-03T19:26:11Z No. of bitstreams: 1 Eduardo Reuter Schneck.pdf: 5168869 bytes, checksum: 117b2eaaed9751212603a9e4d30d8740 (MD5) / Made available in DSpace on 2015-07-03T19:26:11Z (GMT). No. of bitstreams: 1 Eduardo Reuter Schneck.pdf: 5168869 bytes, checksum: 117b2eaaed9751212603a9e4d30d8740 (MD5) Previous issue date: 2013-01-15 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nos últimos anos, tem sido expressiva a oferta de unidades habitacionais em empreendimentos habitacionais de interesse social (EHIS), sendo a maioria fomentada por programas de subsídio e financiamento do governo federal. Em contrapartida, o grande número de obras acaba por aumentar os impactos ao meio ambiente, inerentes ao processo de produção dos edifícios. Além disso, verifica-se no setor uma preferência por edificações cujo tipo arquitetônico adotado é possivelmente mais oneroso do que outras alternativas, além de uma reduzida qualidade das unidades habitacionais. Portanto, a eficiência na execução destes empreendimentos é um aspecto relevante no que diz respeito à otimização no uso dos recursos - tanto naturais como financeiros. No âmbito do conceito do tripé da sustentabilidade, torna-se fundamental o conhecimento das relações do tipo arquitetônico e demais decisões tomadas na etapa de projeto, quando se tem maior influência em fatores que podem reduzir custos, aprimorar quesitos de habitabilidade e ainda minimizar os impactos ambientais. Neste sentido, o objetivo principal desta pesquisa é investigar a influência do tipo arquitetônico em impactos ambientais, no custo e em quesitos de habitabilidade em empreendimentos habitacionais de interesse social (EHIS). Para tanto, foi utilizado o projeto e o orçamento de um EHIS localizado no município de São Leopoldo/RS, fornecidos por uma empresa construtora e cujo tipo arquitetônico com planta em forma H é amplamente difundido na região. A partir desse projeto, denominado Projeto-base, foram feitas simulações do tipo arquitetônico visando aprimorar quesitos de habitabilidade e aumentar o índice econômico de compacidade (IeC), partindo do pressuposto de que com o aumento do IeC reduz-se a quantidade de materiais aplicados nos projetos e, consequentemente, minimiza-se os impactos ambientais além dos custos de produção. Os projetos simulados, denominados Projetos-propostos, tiveram a energia incorporada (EI) e a emissão de CO2 dos materiais estimadas, com o intuito de compará-las com o Projeto-base. Em seguida, foram investigadas as diferenças no custo e também em quesitos de habitabilidade, visando à comparação entre o Projeto-base e os Projetos-propostos. Os resultados apontam para uma redução de 7% da EI e 8% de emissão de CO2 em benefício do projeto-proposto. Em termos de custos de produção, o projeto-proposto apresentou redução de 7%, além de melhorias nos quesitos de habitabilidade como conforto térmico e lumínico, funcionalidade e flexibilidade de planta. / In recent years, there has been a significant supply of housing units in social housing design (SHD), mostly fomented by grant programs and federal government funding. In contrast, the large number of works ultimately increase environmental impacts, inherent in the process of buildings production. Still, there are lots of buildings whose architectural type adopted are demonstrably more expensive than other alternatives, with a reduced quality in housing units. Therefore, the efficient implementation of these projects is an important aspect with regard to optimizing the use of resources - both natural and financial. Under the concept of the triple bottom line, it is crucial to understand the relationships of the type and other architectural decisions taken at the design stage, when it has the greatest influence on factors that can reduce costs, improve habitability and also minimize the environment impacts. In this sense, the main objective of this research is to investigate the influence of architectural type in environmental impacts, cost and habitability in social housing design (SHD). For this, we used the design and budget of a SHD located in São Leopoldo/RS and whose H-shaped design is widespread in the region. From that project, called Base-project, simulations were made of plants aiming to improve habitability questions and increase the economic index of compactness (EIC), on the assumption that with increasing EIC it is possible to reduce the amount of materials used in projects and hence to minimize environmental impacts and production costs. The Proposed-projects had the embodied energy (EE) and CO2 emissions of materials estimated, in order to compare them with the Base-project. Next, it was investigated the differences in cost and also in habitability, evaluated and compared among all projects. The results indicate a reduction of 7% of EE and 8% of CO2 emissions in favor of the Proposed-project. In terms of production costs, the Proposed-project declined by 7%, in addition to improvements in habitability such as luminic and thermal comfort, functionality and flexibility of the plant.
68

Correlação entre compacidade, energia incorporada e emissões de CO2, em projetos de habitação de interesse social / Correlation betwenn design compactness and constructive systems applied in social housing with embodied energy and CO2 emissions

Postay, Renata 27 March 2015 (has links)
Submitted by Maicon Juliano Schmidt (maicons) on 2015-08-06T18:22:40Z No. of bitstreams: 1 Renata Postay.pdf: 3569727 bytes, checksum: 4d066a333e97647bdda37f1b5c173ac2 (MD5) / Made available in DSpace on 2015-08-06T18:22:40Z (GMT). No. of bitstreams: 1 Renata Postay.pdf: 3569727 bytes, checksum: 4d066a333e97647bdda37f1b5c173ac2 (MD5) Previous issue date: 2015-03-27 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Ministério das Cidades / UNISINOS - Universidade do Vale do Rio dos Sinos / A construção civil consome uma grande quantidade de matérias primas e energia. No consumo de energia especificamente, o segmento residencial é muito expressivo pois utiliza o equivalente aos setores comercial e público juntos, em todas as fontes de energia, envolvendo desde a energia para a produção de materiais e componentes, como a energia utilizada na fase de uso das edificações. No Brasil, o setor de habitação de interesse social (HIS) teve um impulso significativo com o Programa Minha Casa Minha Vida (PMCMV), que objetiva a redução do deficit habitacional brasileiro e a promoção do crescimento econômico. Práticas de ações voltadas à economia e otimização da construção, desde a fase de projeto até a execução, são muito oportunas, tendo em vista a atual crise energética que o país vem enfrentando e a escala do segmento de HIS. Neste contexto, o projeto tem papel crucial como indutor da racionalização da construção, pois, a escolha dos materiais e decisões quanto à arquitetura tem influência direta no consumo de materiais e impactos relacionados. O estudo busca investigar o efeito da compacidade do projeto (através do índice econômico de compacidade – IeC) em diferentes sistemas construtivos, utilizados em empreendimentos de habitação de interesse social (EHIS), na energia incorporada (EI) e nas emissões de CO2. A pesquisa analisou cinco projetos de edifícios do PMCMV, e para cada um considerou três sistemas construtivos (alvenaria estrutural com blocos cerâmicos, alvenaria estrutural com blocos de concreto e paredes de concreto). A pesquisa foi conduzida através de três etapas: (1) quantificação dos materiais dos projetos; (2) análise da energia incorporada e emissões de dióxido de carbono (CO2) dos materiais de construção através de dados publicados na literatura e em dados do software Cambridge Engineering Select; (3) verificação da correlação entre compacidade, energia incorporada e emissões de CO2. Quanto ao consumo de materiais, os resultados mostram diferença aproximada de 20% em massa (kg) entre os projetos com menor e maior índice econômico de compacidade, e diferença entre 16% a 20% na análise de EI e emissões de CO2, quando são analisados projetos de um mesmo sistema construtivo. / Civil construction consumes a large amount of raw materials and energy. In energy consumption specifically, the residential segment is very significant because it uses, in all energy sources, the equivalent of the commercial and public sectors together, ranging from the energy to materials and components production, such as the energy used in the use phase of buildings. In Brazil, the social housing sector had a significant growth with the program “Minha Casa Minha Vida (MCMV)” (my house, my life), which aims to reduce the Brazilian housing deficit and to promote economic growth. Actions aimed at saving and optimization of construction are very timely, from the design stage to execution, given the current energy crisis the country is facing, and the scale of social housing segment. In this context, the design plays a crucial role as an inducer of the rationalization of construction, therefore, the choice of materials and decisions on the architecture has a direct influence on materials consumption and related impacts. The study aims to investigate the relationship between design compactness (through economic index of compactness) and construction systems used in social housing developments (EHIS) with embodied energy and CO2 emissions. The research examined five designs of buildings of MCMV, considering construction systems (structural masonry with ceramic bricks, masonry with concrete blocks and concrete walls) for each design. The study was conducted through three steps: (1) quantification of the materials of the designs; (2) analysis of the embodied energy and carbon dioxide (CO2) emissions, from data published in the literature and in the CES Selector software; (3) verification of the relationship between compactness and construction systems, with consumption of EI and CO2 emissions. Regarding the consumption of materials, the results show an approximate 20% difference in weight (kg) between projects with lower and higher economic index of compactness, and the difference between 16% to 20% in EI analysis and CO2 emissions, considering the same construction system.
69

Resultados de existência para alguns problemas não lineares com valores na fronteira de equações diferenciais / Existence results for some nonlinear problems of boundary value differential equations.

Santos, Dionicio Pastor Dallos 26 May 2017 (has links)
O principal objetivo deste trabalho é estudar a existência de soluções para alguns problemas de valores de contorno de equações diferenciais ordinárias não lineares em dimensão finita e infinita. Todos os sistemas considerados nesta investigação são transformados em equações funcionais nas quais o objetivo é encontrar um ponto fixo de um oportuno operador definido em um espaço de funções (que depende do problema estudado). Para isso, faremos uso do grau de Leray-Schauder e de um conceito de grau topológico, devido a R. Nussbaum, para perturbações não compactas da identidade em espaços de Banach. / The main purpose of this work is to study the existence of solutions to some boundary value problems for nonlinear ordinary differential equations in finite and infinite dimension. All systems considered in this research are transformed into functional equations in which the objective is to find a fixed point of a suitable operator defined in a space of functions (which depends on the studied problem). To do this, we use the Leray-Schauder degree and a concept of topological degree due to R. Nussbaum for non-compact perturbations of identity in Banach spaces.
70

Resultados de existência para alguns problemas não lineares com valores na fronteira de equações diferenciais / Existence results for some nonlinear problems of boundary value differential equations.

Dionicio Pastor Dallos Santos 26 May 2017 (has links)
O principal objetivo deste trabalho é estudar a existência de soluções para alguns problemas de valores de contorno de equações diferenciais ordinárias não lineares em dimensão finita e infinita. Todos os sistemas considerados nesta investigação são transformados em equações funcionais nas quais o objetivo é encontrar um ponto fixo de um oportuno operador definido em um espaço de funções (que depende do problema estudado). Para isso, faremos uso do grau de Leray-Schauder e de um conceito de grau topológico, devido a R. Nussbaum, para perturbações não compactas da identidade em espaços de Banach. / The main purpose of this work is to study the existence of solutions to some boundary value problems for nonlinear ordinary differential equations in finite and infinite dimension. All systems considered in this research are transformed into functional equations in which the objective is to find a fixed point of a suitable operator defined in a space of functions (which depends on the studied problem). To do this, we use the Leray-Schauder degree and a concept of topological degree due to R. Nussbaum for non-compact perturbations of identity in Banach spaces.

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