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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

Les effets de l'Internet sur les règles de conflit de compétence internationale : comparaison entre les droits irakien, français et américain / The effects of the Internet on international competence conflict rules

Obbed, Khair Al Deen Kadhim 28 June 2016 (has links)
La législation irakienne définit le contrat comme étant l’union d'une offre faite par la partie contractante avec l'acceptation d'une autre partie et ce de manière à établir les effets dans l'objet du contrat. Ainsi, la place occupée par le contrat de vente en droit irakien est importante. Lorsque les parties relèvent d’ordres juridiques différents, leurs rapports sont régis par le droit international privé, qui détermine le tribunal apte à trancher le litige. Cette thèse de doctorat vise alors à vérifier la capacité à appliquer les règles de conflit de compétence internationale en droit irakien sur des contrats « virtuels » ou dématérialisés. Comme nous le verrons, dans ce domaine, « virtuel » ne veut pas pour autant dire que ce contrat n’est pas réel, comme le spécifie très clairement la loi irakienne. Il reste rattaché au territoire. Le problème est que le droit irakien, en ignorant les notions de frontière et de territorialité, ne reconnaît pas sa propre « immatérialité ». Cette réalité dans les textes et la pratique implique que les opérations qui se produisent sur Internet ne sont pas prises en compte par les règles de conflits de compétence internationale. C’est la raison pour laquelle nous avons souhaité vérifier et comprendre la capacité et l’effectivité des règles de conflit de compétence internationale dans le cadre de litiges sur Internet. Ce faisant, nous espérons mettre en lumière les règles les plus appropriées, qui correspondent le mieux à la nature du contrat virtuel, à savoir son immatérialité. Pour ce faire, nous entreverrons quelques développements sur les litiges de l’Internet. Ainsi nous disposons de deux domaines de recherche : un premier au niveau de la législation nationale, comme le droit français et le droit américain ; un deuxième au niveau des conventions internationales, comme les conventions des Nations-Unies en 2005, la convention de la Haye en 2005, la convention de Bruxelles en 1968 ou encore les règlements de Bruxelles 2000 et 2012. / Iraqi law defines the contract as the union of an offer made by the contracting party with the acceptance of another party and that in order to establish the effects in the contract. The place of the sales contract under Iraqi law is important. When the parties come from different legal orders, their relations are governed by the private international law which determines the court will decide. This thesis research aims to test the ability to apply the international rules of conflict of jurisdiction under Iraqi law on the virtual contract, which is paperless. We shall see, this is not to mean however that the contract is not real, as clearly specifies Iraqi law. It remains attached to the territory. In contrast, the Iraqi law does not recognize its immaterial that meanwhile ignores borders and notions of territoriality. This reality in the texts and practices therefore makes transactions that occur on the Internet are not taken into account by the rules of international jurisdiction conflicts. That is why, we wanted to check and understand the capacity and effectiveness of international jurisdiction conflict rules in the context of Internet disputes. So we will try to find the most appropriate rules, consistent with the nature of the virtual contract, namely its immateriality. This search will reveal developments in litigation of the Internet. Thus, it takes two directions: first at the national legislation, such as French and US law. Second, at the stage of international conventions such as the United Nations Conventions 2005, Hague Convention, the Brussels Convention 1968 and the 2000 and 2012 regulations.
162

Structural Behaviour of Lapped Cold-Formed Steel Z-Shaped Purlin Connections with Vertical Slotted Holes

Liu, Jingnan January 2014 (has links)
Lapped joints of cold-formed steel (CFS) Z-shaped purlins are extensively used in metal building roof systems. The research that has been carried out so far for these lapped connections is primarily focused on connections with round holes. However, the lapped connections with vertical slotted holes are extensively used in current construction practice to simplify the erection of continuous Z-shaped roof purlins. There is no design guideline or recommendation available for CFS Z-purlin lapped connections with vertical slotted holes. Presented in this paper are the results of an experimental study and analysis of the structural behaviour of lapped CFS Z-shaped purlin connections with vertical slotted holes. 42 flexural tests were performed on lapped CFS Z-shaped purlins with vertical slotted connections with different lap lengths, purlin depths, thicknesses and spans. The flexural strength and deflection of each specimen were measured. The characteristics of moment resistance and flexure stiffness of the lapped purlins were computed. The test results show that the lapped purlins with vertical slotted holes may be more flexible than the lapped purlins with round holes or continuous purlins without lapped joint. Thus, the slotted connections may need greater lap lengths to achieve full stiffness of continuous purlins. The results also indicate that the characteristics of moment resistance and flexural stiffness in the slotted connections are dependent on the ratio of lap length to purlin depth, the ratio of lap length to purlin thickness, the ratio of purlin depth to purlin thickness, and the ratio of lap length to span. Based on the results, design recommendations for evaluating the moment resistance and flexural stiffness of lapped slotted connections were proposed.
163

Wage rigidities in chosen EU countries

Janus, Ondřej January 2015 (has links)
The objective of this thesis is to estimate the real wage rigidities in chosen EU countries and their influence on long term unemployment. Two main approaches used in this thesis are multiple regression analysis applied on Phillips curve and Structural VAR. The results show the development of wage flexibility before and after the crisis, heterogeneity of wage flexibility across the chosen EU countries and positive correlation between wage flexibility and low long-term unemploy-ment rate.
164

Controle de ressonância de base de máquinas rotativas por meio de forças axiais

Pádua, Eduardo de Melo January 2017 (has links)
Orientador: Prof. Dr. Reyolando M. L. R. F. Brasil / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Mecânica, 2017. / Neste trabalho realiza-se um estudo do efeito causado pela alteracao da rigidez geometrica, por meio de forcas axiais, na frequencia natural de bases de maquinas rotativas, na forma de viga e portico plano, todos metalicos, no intuito de tira-las na ressonancia ou proximo dessa regiao. Essa regiao proxima da ressonancia e chamada de regiao fora de seguranca e compreende o intervalo que comeca em 20% abaixo da frequencia da maquina ate 25% acima dela. Duas ferramentas foram utilizadas para realizar o estudo, Metodo de Rayleigh e Metodo dos Elementos Finitos (MEF). Na viga estuda-se um perfil estrutural de um tubo retangular em aco estrutural, utilizando o Metodo de Rayleigh e o MEF. Ja o portico e estudado somente pelo MEF, so que mais perfis foram analisados desse mesmo tubo. No caso da base como viga, sem carregamento algum, ela se mostrou dentro na zona perigosa, tanto por Rayleigh como por MEF. Uma intervencao com forcas axiais foi realizada para estabilizar as bases. No portico tanto portico, o perfil 60x60 nao ficou dentro da zona perigosa, ja os demais, 80x80 e perfil ¿§, ficaram dentro da regiao { 0,8¿¶, 1,25¿¶ }. O estudo mostrou que a rigidez geometrica / In this work a study of the effect caused by the alteration of the geometric stiffness, by means of axial forces, in the natural frequency of bases of rotating machines, in the form of beam and plan portico, all metallic, in order to take them out in the resonance or near this region. This region near the resonance is called unsafe region, and comprises the range starting at 20% below the frequency of the machine and to 25% above it. Two tools were used to carry out the study, Rayleigh Method and Finite Element Method (FEM). In the beam, a structural profile of a rectangular tube in structural steel is studied, using the Rayleigh Method and MEF. Already the portico is studied only by MEF, except that more profiles were analyze in this same tube. In the case of the base as beam, without any loading, it showed itself inside the dangerous zone, by both Rayleigh and MEF. An axial force intervention was performed to stabilize the bases. In the planar portal frame, the 60x60 profile was not inside the dangerous zone, while the others, 80x80 and profile É, were within the region {0.8Ù, 1.25Ù}. The study showed that the geometric stiffness has a close relation with the natural frequencies in solid structures.
165

Estudo das ligações por conectores de chapas com dentes estampados em peças estruturais de madeira

Martins, Odilon [UNESP] 26 July 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-26Bitstream added on 2014-06-13T20:08:04Z : No. of bitstreams: 1 martins_o_me_ilha.pdf: 1853643 bytes, checksum: e5ed74dccf9c216b529f9bef47b8a14d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No Brasil, é comum o uso de estruturas treliçadas de madeira na construção de coberturas nas edificações e, que, na maioria das vezes, são feitas de forma artesanal ou empírica. Para que haja uma otimização na produção dessas estruturas, através da industrialização, é conveniente o conhecimento e o domínio dos sistemas construtivos disponíveis. A utilização dos conectores metálicos, de chapa com dentes estampados (CDE) nas ligações dos elementos estruturais das treliças, é considerada, pela literatura, uma boa opção de sistema construtivo em escala industrial. Neste trabalho foram determinadas a resistência e a rigidez das ligações por conector CDE, em peças estruturais de madeira, para as classes de resistência: C20; C30 e C40, através dos modos básicos de ruptura das peças ligadas, que são: arrancamento dos dentes na peça de madeira; cisalhamento e tração da chapa. Também foi verificada a influência da variação na umidade das peças de madeira, ao serem prensadas pelo conector CDE, na resistência e rigidez da ligação, visando com isso, contribuir com a Revisão da Norma Brasileira (NBR-7190/97). / The usage of wood trusses is common in the construction of roofs in Brazil, the most of the times are built in way craft or empiric. Obtaining an optimization in the production of these structures, through the industrialization, it is convenient the knowledge and the domain of the available constructive systems. The usage of the metallic connectors, as the metal connectors plates (MCP) in the connections of the structural elements of the truss is considered, for the literature, a nice option of constructive system in industrial scale. In this work, the resistance and the rigidity of the connections for connector MCP, in structural pieces of wood, for the resistance classes C20; C30 and C40, were certained through the basic manners of rupture of the linked pieces are: pull-out of the teeth in the wood piece; cut and traction of the connector. The influence of the variation in the humidity of the wood pieces as they are pressed by the connector MCP, in the resistance and the rigidity of the connections was verified as well, seeking with that, to contribute with Brazilian Code (NBR-7190/97) Revision.
166

Determinação teórico-experimental da rigidez ao cisalhamento devido à restrição das telhas conectadas nas terças

Pinto, Eduardo Lourenço [UNESP] 19 May 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-05-19Bitstream added on 2014-06-13T19:32:22Z : No. of bitstreams: 1 pinto_el_me_ilha.pdf: 1624906 bytes, checksum: 5bc2d5cfa5a9fecd4b7df0008cf99be3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Fundação de Ensino Pesquisa e Extensão de Ilha Solteira (FEPISA) / O desenvolvimento da presente pesquisa tem a finalidade de estudar um dos efeitos principais de restrição de telhas conectadas nas terças, que é a rigidez ao cisalhamento. O valor da rigidez ao cisalhamento é determinado pela influência da restrição da telha no deslocamento lateral da terça sobre o seu eixo longitudinal, em função do espaçamento dos parafusos de conexão. Para a determinação da rigidez ao cisalhamento foi utilizado um procedimento experimental, semelhante ao modelo numérico, referido como DOUBLE BEAM SHEAR TEST - DBST, que permite avaliar a restrição dada pela telha à terça ao cisalhamento. Para os testes do modelo DBST foi utilizado o Laboratório de Engenharia Civil, onde foram ensaiadas séries desse conjunto para a determinação da rigidez ao cisalhamento. As terças são constituídas de perfil formado a frio. As distâncias entre as terças são compreendidas entre os valores de 1000 a 2300 mm. As telhas são do tipo ondulada com altura de 17 mm e trapezoidal com altura compreendida entre 25 mm e 100 mm. As espessuras das telhas estão entre os valores de 0,43 mm e 0,80 mm. / The development of the present research has the purpose to study one of the main effect of restriction of the sheeting connected in purlin, that it is the rigidity to the shear. The value of the rigidity to the shear is determined by the influence of the restriction of the sheeting in the lateral displacement of purlin on its longitudinal axis, in function of the spacing of the connection screws. For the determination of the rigidity to the shear an experimental procedure was used, similar to the numerical model, related as DOUBLE BEAM SHEAR TEST - DBST, that allows to evaluate the restriction given for the sheeting to purlin to the shear. For the tests of model DBST the Laboratory of Civil Engineering was used, where had been assayed series of this set for the determination of the rigidity to the shear. Purlins are constituted of the cold formed profile. The distances between purlins are understood between the values of 1000 the 2300 mm. The sheeting are of the type wavy with height of 17 mm and trapezoidal with height understood between 25 mm and 100 mm. The thicknesses of the sheeting are between the values of 0,43 mm and 0,80 mm.
167

Constructive approaches to the rigidity of frameworks / Constructive approaches to the rigidity of frameworks

Nguyen, Viet Hang 17 October 2013 (has links)
La théorie de la rigidité étudie l'unicité des réalisations des graphes, i.e., des charpentes. Initialement motivée par l'ingénierie des structures, la théorie de la rigidité trouve aujourd'hui des applications dans plusieurs domaines importants comme la prédiction de la flexibilité des protéines, la conception assistée par ordinateur, la localisation dans les réseaux des capteurs, etc. Cette thèse traite une grande variété de problèmes concernant différents types de rigidité, qui correspondent à différents niveaux d'unicité (locale/infinitésimale, globale et universelle) dans des modèles variés de charpentes. D'abord, nous développons des résultats sur la construction récursive et la décomposition des graphes avec des conditions mixtes de sparsité ainsi que des résultats sur le packing des arborescences avec des contraintes de matroïde. Ces résultats sont alors utilisés pour obtenir des caractérisations de la rigidité infinitésimale des charpentes avec des contraintes mixtes. Nous étudions aussi l'effet des opérations d'extension sur des charpentes et étendons un résultat connu sur la préservation de la rigidité globale d'$1$-extension dans les charpentes à direction et à longueur de la dimension deux aux dimensions supérieures. Pour la rigidité universelle, un sujet que l'on connait très peu, nous obtenons une caractérisation complète pour la classe des charpentes biparties complètes sur la ligne. Nous généralisons aussi une condition suffisante pour la rigidité universelle des charpentes en permettant des positions non générales. / The theory of rigidity studies the uniqueness of realizations of graphs, i.e., frameworks. Originally motivated by structural engineering, rigidity theory nowadays finds applications in many important problems such as predicting protein flexibility, Computer-Aided Design, sensor network localization, etc. The present thesis treats a wide range of problems concerning different kinds of rigidity, corresponding to different scopes of uniqueness (local/infinitesimal, global and universal), in various types of frameworks. First, we develop results in inductive construction and decomposition of graphs with mixed sparsity conditions as well as results on the packing of arborescences with matroidal constraints. These results are then used to obtain characterizations of infinitesimal rigidity in frameworks with mixed constraints. We also investigate the effect of extension operations on frameworks and extend a known result on the global rigidity preservation of $1$-extension on direction-length frameworks in dimension two to all dimensions. For universal rigidity, where little is known, we obtain a complete characterization for the class of complete bipartite frameworks on the line. We also generalize a sufficient condition for the universal rigidity of frameworks by allowing non-general positions.
168

Determinação teórico-experimental da rigidez ao cisalhamento devido à restrição das telhas conectadas nas terças /

Pinto, Eduardo Lourenço. January 2006 (has links)
Orientador: Renato Bertolino Junior / Banca: José Antonio Matthiesen / Banca: Francisco Carlos Rodrigues / Resumo: O desenvolvimento da presente pesquisa tem a finalidade de estudar um dos efeitos principais de restrição de telhas conectadas nas terças, que é a rigidez ao cisalhamento. O valor da rigidez ao cisalhamento é determinado pela influência da restrição da telha no deslocamento lateral da terça sobre o seu eixo longitudinal, em função do espaçamento dos parafusos de conexão. Para a determinação da rigidez ao cisalhamento foi utilizado um procedimento experimental, semelhante ao modelo numérico, referido como DOUBLE BEAM SHEAR TEST - DBST, que permite avaliar a restrição dada pela telha à terça ao cisalhamento. Para os testes do modelo DBST foi utilizado o Laboratório de Engenharia Civil, onde foram ensaiadas séries desse conjunto para a determinação da rigidez ao cisalhamento. As terças são constituídas de perfil formado a frio. As distâncias entre as terças são compreendidas entre os valores de 1000 a 2300 mm. As telhas são do tipo ondulada com altura de 17 mm e trapezoidal com altura compreendida entre 25 mm e 100 mm. As espessuras das telhas estão entre os valores de 0,43 mm e 0,80 mm. / Abstract: The development of the present research has the purpose to study one of the main effect of restriction of the sheeting connected in purlin, that it is the rigidity to the shear. The value of the rigidity to the shear is determined by the influence of the restriction of the sheeting in the lateral displacement of purlin on its longitudinal axis, in function of the spacing of the connection screws. For the determination of the rigidity to the shear an experimental procedure was used, similar to the numerical model, related as DOUBLE BEAM SHEAR TEST - DBST, that allows to evaluate the restriction given for the sheeting to purlin to the shear. For the tests of model DBST the Laboratory of Civil Engineering was used, where had been assayed series of this set for the determination of the rigidity to the shear. Purlins are constituted of the cold formed profile. The distances between purlins are understood between the values of 1000 the 2300 mm. The sheeting are of the type wavy with height of 17 mm and trapezoidal with height understood between 25 mm and 100 mm. The thicknesses of the sheeting are between the values of 0,43 mm and 0,80 mm. / Mestre
169

A influência da não-linearidade física do concreto armado na rigidez à flexão e na capacidade de rotação plástica. / The influence of physical non-linearity of the reinforced concrete on flexural rigidity and on plastic rotation capacity.

Roberto Buchaim 18 July 2001 (has links)
O presente trabalho é uma contribuição para o esclarecimento e a quantificação das influências na deformabilidade e na capacidade portante de elementos unidimensionais de concreto armado em solicitação plana, decorrentes da não-linearidade física dos materiais concreto e aço, bem como da fissuração e do enrijecimento da armadura tracionada, também na sua fase plástica. Para aplicações práticas determinam-se a rigidez à flexão e a capacidade de rotação plástica dos elementos estruturais, o que permite limitar com mais precisão e coerência a demanda de rotação plástica obtida na análise. De início, descrevem-se os comportamentos não-lineares do concreto e do aço, aplicando-se conceitos da Mecânica da Fratura, bem como a atuação conjunta destes materiais, sob os aspectos de aderência e de fissuração. O núcleo deste trabalho concentra-se na obtenção do diagrama momento-curvatura e dos seus pontos principais, e na subseqüente determinação da capacidade de rotação plástica dos mencionados elementos. Consideram-se as seções geradas a partir da seção duplo T assimétrico, com várias camadas de armadura, sujeitas à flexão composta normal. Com dados deste diagrama e através do modelo da viga equivalente simétrica, posteriormente estendido à viga equivalente assimétrica e às vigas contínuas de pórticos planos, determina-se a capacidade de rotação plástica, considerando-se nesta suas múltiplas influências. Por fim, comparam-se os resultados teóricos e experimentais da capacidade de rotação plástica, e resumem-se as principais conclusões encontradas e os pontos que exigem subseqüente desenvolvimento. / The present study is a contribution to the enlightenment and evaluation of the influences on deformability and load carrying capacity of one-dimensional elements of reinforced concrete subject to in-plane loading, arisen from the constitutive non-linearity of concrete and steel, as well as from the concrete cracking and the tension stiffening of the reinforcement, prior and after yielding. For practical applications, the flexural rigidity and the plastic rotation capacity of structural elements are determined, which makes it possible to limit, more precisely and coherently, the plastic rotation demand coming from the analysis. Firstly, the non-linear behaviors of concrete and steel are described, applying concepts of Fracture Mechanics, and then the joint action of both materials concerning bond and cracking is studied. The core of this study lies on obtaining the bending moment-curvature diagram, specially its main points, and on the subsequent determination of the plastic rotation capacity of the aforementioned elements. The cross-sections generated from an asymmetric double T cross-section are considered, with several layers of reinforcement, acted upon simple or combined bending about one principal axis. With data based on this diagram and through the model of equivalent symmetric beam, later extended to equivalent asymmetric beam and to continuous beams of plane frames, the plastic rotation capacity is determined, considering its multiple influences. Finally, theoretical and experimental results of plastic rotation capacity are compared, and the main conclusions and points in need of subsequent development are summarized.
170

Rigidez da esfera no espaÃo euclidiano / Sphere rigidity in the euclidean space

Neilha Marcia Pinheiro 23 May 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Neste trabalho, provamos novos resutados de rigidez para hipersuperfÃcies quase-Einsteins no espaÃo euclidiano, baseado-se nos resultados pinching do autovalor. EntÃo, nÃs deduzimos alguns resultados anÃlogos para hipersuperfÃcies quase-umbÃlicas e uma nova caracterizaÃÃo de esferas geodÃsicas / In this work, we prove new rigidity results for almost-Einstein hypersurfaces of the Euclidean space, based on previous eigenvalue pinching results. Then, we deduce some comparable result for almost-umbilic hypersurfaces and new characterizations of geodesic spheres.

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