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De, Stefano Cosimo Antonio. "Wave propagation in bi-dimensional periodic tensegrity materials and structures." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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The study of the metamaterials and the phononic crystals is unavoidable for the development of innovative isolation techniques (acoustic, seismic or thermal) thanks to their
control properties over the propagation of elastic waves at different wavelength scales. Making use of the spatial periodicity of such materials, it is possible to study the unit cell individually and only subsequently extending the type harmonic plane wave Solution of the equations of motion to the whole domain by applying the Floquet-Bloch theorem. In this thesis we study the dispersion curves obtained in the cases of one-dimensional and two-dimensional lattices through scripts in Matlab. Thus we obtain the characteristic band diagrams of the dispersion curves of these materials (pass band, stop band, bandgap and fano resonance). In particular, the present work focuses on the study of a lattice whose cells are tensegrity structures modeled as a reticular structure with the
lamped mass approach: the study is reduced to the simplest case of two-dimensional monoatomic lattice. From the dynamic analysis of this model we obtain the dispersion curves of the pre-tension variation in the elements.
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Saleur, Benoît. "Trois problèmes géométriques d'hyperbolicité complexe et presque complexe." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112256/document.
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Cette thèse est consacrée à l'étude de trois problèmes d'hyperbolicité complexe et presque complexe. La première partie est dédiée à la recherche d'une conséquence quantitative de l'hyperbolicité au sens de Kobayashi, qui est une propriété qualitative. Le résultat obtenu prend la forme d'une inégalité isopérimétrique qui évoque l'inégalité d'Ahlfors relative aux recouvrements des surfaces de surfaces. Sa démonstration est purement riemannienne.La deuxième partie de la thèse est consacrée à la démonstration d'une version presque complexe du théorème de Borel, qui affirme que les courbes entières dans le plan projectif complexe évitant quatre droites en position générale sont linéairement dégénérées. Dans un plan projectif presque complexe, les J-droites substituent aux droites projectives et nous disposons d'un énoncé analogue pour les J-courbes entières. La démonstration de ce résultat repose sur l'utilisation de projections centrales et sur la théorie de recouvrement des surfaces d'Ahlfors.La dernière partie est consacrée à la démonstration d'une version presque complexe du théorème de Bloch, qui affirme qu'une suite non normale de disques holomorphes du plan projectif évitant quatre droites en position générale converge, en un certain sens, vers une réunion de trois droites. Notre résultat implique en particulier l'hyperbolicité du complémentaire dans le plan projectif presque complexe de quatre J-droites modulo trois J-droitesThis thesis is dedicated to the study of three problems of complex and almost complex hyperbolicity. Its first part is dedicated to the research of a quantitative consequence to Kobayashi hyperbolicity, which is a qualitative property. The result we obtain has the form of an isoperimetric inequality that suggests Ahlfors' inequality, the central result of the theory of covering surfaces. Its proof uses only riemannian tools.The second part of the thesis is dedicated to the proof of an almost complex version of Borel's theorem, which says that an entire curve in the compex preojective plane missing four lines in general position is degenerate. In an almost compex context, we can obtain a similar result for entire J-curves just by replacing projective lines by J-lines. The proof of this result uses central projections and Ahlfors' theory of covering surfaces.The last part is dedicated to the proof of an almost complex version of Bloch's theorem, which says that given a sequence of holomorphic discs in the projective plane, either it is normal, either it converges in some sens to a reunion of three lines. Our result will show in particular that the complementary set of four J-lines in general position is hyperbolic modulo three J-lines
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Bogdanic, Dusko. "Graded blocks of group algebras." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:faeaaeab-1fe6-46a9-8cbb-f3f633131a73.
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In this thesis we study gradings on blocks of group algebras. The motivation to study gradings on blocks of group algebras and their transfer via derived and stable equivalences originates from some of the most important open conjectures in representation theory, such as Broue’s abelian defect group conjecture. This conjecture predicts the existence of derived equivalences between categories of modules. Some attempts to prove Broue’s conjecture by lifting stable equivalences to derived equivalences highlight the importance of understanding the connection between transferring gradings via stable equivalences and transferring gradings via derived equivalences. The main idea that we use is the following. We start with an algebra which can be easily graded, and transfer this grading via derived or stable equivalence to another algebra which is not easily graded. We investigate the properties of the resulting grading. In the first chapter we list the background results that will be used in this thesis. In the second chapter we study gradings on Brauer tree algebras, a class of algebras that contains blocks of group algebras with cyclic defect groups. We show that there is a unique grading up to graded Morita equivalence and rescaling on an arbitrary basic Brauer tree algebra. The third chapter is devoted to the study of gradings on tame blocks of group algebras. We study extensively the class of blocks with dihedral defect groups. We investigate the existence, positivity and tightness of gradings, and we classify all gradings on these blocks up to graded Morita equivalence. The last chapter deals with the problem of transferring gradings via stable equivalences between blocks of group algebras. We demonstrate on three examples how such a transfer via stable equivalences is achieved between Brauer correspondents, where the group in question is a TI group.
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Gramain, Jean-Baptiste. "Generalized Block Theory." Phd thesis, Université Claude Bernard - Lyon I, 2005. http://tel.archives-ouvertes.fr/tel-00010451.
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Cette these presente quelques aspects de la theorie des blocs generalises pour les groupes finis. Apres une breve description des theories classique et generalisee, on y etudie les proprietes des blocs generalises de certains groupes. On montre l'existence d'isometries parfaites generalisees dans trois familles de groupes de Lie de rang 1, generalisant ainsi une conjecture de M. Broue. On etudie ensuite le concept de groupe de Cartan generalise, et une formule est donnee pour l'ordre dans le groupe de Cartan des caracteres du groupe symetrique. Enfin, on definit des blocs generalises dans les groupes lineaires finis, et on montre que certaines unions de blocs de caracteres unipotents satisfont un analogue de la Conjecture de Nakayama ainsi qu'un analogue du Deuxieme Theoreme de Brauer.
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Montúfar, López Hernán Roberto. "Teoria de Conley para campos Gutierrez-Sotomayor." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307543.
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Orientador: Ketty Abaroa de RezendeTese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica
Made available in DSpace on 2018-08-16T08:12:09Z (GMT). No. of bitstreams: 1 MontufarLopez_HernanRoberto_D.pdf: 8015438 bytes, checksum: 1175f8d0f78fe476b09178b6e50f10ec (MD5) Previous issue date: 2010
Resumo: Em [6] são apresentadas condições necessárias e suficientes para a estabilidade estrutural e o teorema de densidade para campos de vetores em 2-variedades com singularidades simples dos seguintes tipos: cone, guarda-chuva de Whitney, ponto duplo e ponto triplo. Nesta tese, estudamos os fluxos induzidos por estes campos de vetores, que denominamos fluxos Gutierrez-Sotomayor, do ponto de vista topológico utilizando a teoria de Conley. Apresentamos uma fórmula dinâmico-topológica que relaciona o índice de Conley de uma variedade com singularidades simples M que possui uma estratificação que a decompõe numa união disjunta da sua parte regular e da sua parte singular. Usando essa estratificação mostramos que se a singularidade está na parte singular S de M o seu índice pode ser calculado tanto com respeito a M como com respeito a S. Definimos uma função de Lyapunov, neste contexto, e mostramos sua existência para fluxos sem órbitas periódicas e sem ciclos singulares. Em seguida, por uma análise da seqüência de homologia longa exata de um par índice determinamos propriedades que um grafo de Lyapunov deve satisfazer para estar associado a um fluxo. Também abordamos a questão da realização de grafos de Lyapunov abstratos. Para isto, primeiramente apresentamos a igualdade de Poincaré-Hopf, para o caso bidimensional, que caracteriza a relação entre o primeiro número de Betti das 1-variedades ramificadas que são fronteiras de um bloco isolante com seu número de componentes de fronteira e o índice numérico de Conley. Em seguida, mostramos que dados números inteiros positivos que satisfaçam a condição de Poincaré-Hopf sempre é possível construir um bloco isolante que satisfaz estes dados dinâmicos e homológicos
Abstract: In [6] a characterization and genericity theorem for C1-structurally stable vector fields tangent to a 2-dimensional compact subset M of Rk are established. Also in [6], new types of structurally stable singularities and periodic orbits are presented. In this thesis we study the continuous flows associated to these vector fields, which we refer to as the Gutierrez-Sotomayor flows on manifolds M with simple singularities using Conley Index Theory. We consider a stratification of M which decomposes it into a union of its regular and singular strata. We prove certain Euler type formulas which relate topology of M and dynamics on the singular strata. We show the existence of a Lyapunov function for Gutierrez-Sotomayor flows without periodic orbits and singular cycles in this context. Using long exact sequence analysis of index pairs we determine necessary and sufficient conditions for a Gutierrez-Sotomayor flow to be defined on an isolating block. We organize this combinatorially with the aid of Lyapunov graphs and using a Poincar'e-Hopf equality we give necessary conditions for a Lyapunov graph to be associated to a Gutierrez-Sotomayor flow and we also prove these conditions are sufficient
Doutorado
Geometria e Topologia
Doutor em Matemática
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Salminen, Adam D. "On the sources of simple modules in nilpotent blocks." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1124221435.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains viii, 87 p. Includes bibliographical references (p. 85-87). Available online via OhioLINK's ETD Center
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Nova, Araujo Miguel Antonio da. "2D Bloch electrons in magnetic fields." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387617.
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Kendall, Toby. "Theoretical models of trade blocs and integrated markets." Thesis, University of Warwick, 2000. http://wrap.warwick.ac.uk/4014/.
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This thesis consists of four main chapters, together with a general introduction and conclusion. The thesis examines, both separately and together, the formation of trade blocs and global market integration. All the models use a partial equilibrium framework, with firms competing as Cournot oligopolists. Chapter 2 presents two models of trade bloc formation under segmented markets. In the first model, with common constant marginal costs, global free trade is optimal for all countries when there are no more than four countries, but with five or more countries there is an incentive to form a trade bloc containing most countries, but excluding at least one. The second model introduces a cost function where a firm's marginal cost is lower when it is located in a larger trade bloc, with little effect on the results. Chapter 3 analyses the formation of trade blocs between countries with different market sizes under segmented markets. The formation of a two country customs union or free trade area will always raise the smaller country's welfare, while the larger country will usually lose from a free trade area, and sometimes from a customs union. Chapter 4, which is joint work with David R. Collie and Morten Hviid, presents a model of strategic trade policy under integrated markets, under complete and incomplete information. In the former case, a low cost country will give an export subsidy which is fully countervailed by the high cost country's import tariff. In the simultaneous signalling game, each country's expected welfare is higher than under free trade. Chapter 5 considers models of trade bloc formation under integrated markets. With common constant costs, there is no incentive for blocs to form. When costs are decreasing in membership of a bloc, either global free trade is optimal or countries would prefer to belong to the smaller of two blocs.
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Ahsani, Sepide. "Wawe propagation in periodic tensegrity structural systems." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
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Periodic structure is a type of periodic medium. Their main characteristics are defined by their unit cell, which is the cell that by repeating it, the lattice is constructed. The main advantage of such structure is that the wave propagation in it can be investigated by using the application of Floquet-Bloch theorem and therefore investigating only a single unit cell. This feature highly reduces the computational cost.
In this work a two-dimensional lattice is built using a tensegrity structural unit cell. A tensegrity structure is consist of tension and compression components arranged in a discontinuous system.
The dispersion curve is plotted along the edges of IBZ to understand the effect of pre-tension and pre-compression on the band gaps in two cases of a lattice made of only tension components, i.e. cables or compression components, i.e. bars, and a two-dimensional tensegrity system.
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Tatsumi, Kazuyoshi, Shunsuke Muto, and Ján Rusz. "New algorithm for efficient Bloch-waves calculations of orientation-sensitive ELNES." Elsevier, 2013. http://hdl.handle.net/2237/20831.
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Cisneros-Molina, Jose Luis. "The regulator, the Bloch group, hyperbolic manifolds, and the #eta#-invariant." Thesis, University of Warwick, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311583.
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Norris, Kimberly Jane. "Virginia's Foundation Blocks for Early Learning: Interpretation and Implementation by Practitioners." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/26293.
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Expectations for accountability have led policy makers to create standards designed to educate children to their highest potential. In addition to k-12 standards, the Commonwealth of Virginia created Foundation Blocks for a state-sponsored preschool program called the Virginia Preschool Initiative.
This study included assessment of Virginia's Foundation Blocks for Early Learning: Comprehensive Standards for Four-Year-Olds as they relate to theories of Piaget, Vygotsky, and Rogoff. This assessment included play, scaffolded instruction, emergent literacy, and spatial reasoning. The Foundation Blocks were examined to determine how they were interpreted and implemented by preschool classroom teachers. Using a case-study format, four volunteer teachers participated in three days of classroom observations, be interviewed, and complete a survey.
Evidence showed that the standards were theoretically based, and the participating teachers' pedagogy included play, emergent literacy, and spatial reasoning. Scaffolded instruction was not observed. There were concerns about teachers' low expectations and low-level questioning techniques.Ph. D.
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Allen, Robert Francis. "A class of operators with symbol on the bloch space of a bounded homogeneous domain." Fairfax, VA : George Mason University, 2009. http://hdl.handle.net/1920/4541.
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Thesis (Ph.D.)--George Mason University, 2009.Vita: p. 158. Thesis director: Flavia Colonna. Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Mathematics. Title from PDF t.p. (viewed Oct. 11, 2009). Includes bibliographical references (p. 150-157). Also issued in print.
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Batista, Cesar Adriano. "Generalizações do teorema de representação de Riesz." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/45/45131/tde-20072009-144313/.
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Dados um espaço de medida (X;A;m) e números reais p,q>1 com 1/p+1/q=1, o Teorema de Representação de Riesz afirma que Lq(X;A;m) é o dual topológico de Lp(X;A;m) e que Loo(X;A; m) é o dual topológico de L1(X;A;m) se o espaço (X;A;m) for sigma-finito. Observamos que a sigma-finitude de (X;A;m) é condição suficiente mas não necessária para que Loo(X;A;m) seja o dual de L1(X;A;m). Os contra-exemplos tipicamente apresentados para essa última identificação são \"triviais\", no sentido de que desaparecem se \"consertarmos\" a medida , transformando-a numa medida perfeita. Neste trabalho apresentamos condições sufcientes mais fracas que sigma-finitude a fim de que Loo(X;A;m) e o dual de L1(X;A;m) possam ser isometricamente identificados. Além disso, introduzimos um invariante cardinal para espaços de medida que chamaremos a dimensão do espaço e mostramos que se o espaço (X;A;m) for de medida perfeita e tiver dimensão menor ou igual à cardinalidade do continuum então uma condição necessária e suficiente para Loo(X;A;m) seja o dual de L1(X;A;m) é que X admita uma decomposição.Given a measure space (X;A;m) and real numbers p,q>1 with 1/p+1/q=1, the Riesz Representation Theorem states that Lq(X;A;m) is the topological dual space of Lp(X;A;m) and that Loo(X;A; m) is the topological dual space of L1(X;A;m) if (X;A; m) is sigma-finite. We observe that the sigma-finiteness of (X;A;m) is a suficient but not necessary condition for Loo(X;A;m) to be the dual of L1(X;A;m). The counter-examples that are typically presented for Loo(X;A;m) = L1(X;A;m)* are \"trivial\", in the sense that they vanish if we fix the measure , making it into a perfect measure. In this work we present suficient conditions weaker than sigma-finiteness in order that Loo(X;A; m) and L1(X;A;m)* can be isometrically identified. Moreover, we introduce a cardinal invariant for measure spaces which we call the dimension of the space and we show that if the space (X;A;m) has perfect measure and dimension less than or equal to the cardinal of the continuum then a necessary and suficient condition for Loo(X;A;m) = L1(X;A;m)* is that X admits a decomposition.
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Silva, Valney Veras da. "ArgumentaÃÃo no discurso parlamentar de legitimaÃÃo da corrupÃÃo polÃtica." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13186.
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nÃo hÃA âArgumentaÃÃo no discurso parlamentar de legitimaÃÃo da corrupÃÃo polÃticaâ, tÃtulo desta tese, tem como objetivo investigar o discurso parlamentar de legitimaÃÃo da corrupÃÃo polÃtica, com foco no exame de como se configuram as relaÃÃes entre discurso, ideologia e estratÃgias linguÃstico-discursivas. Observa-se a corrupÃÃo polÃtica pela dimensÃo discursiva, e nÃo somente pelo viÃs das ciÃncias polÃticas, de modo a perceber que hà um discurso produzido para legitimar tal prÃtica, bem como identificar os recursos velados que a naturalizam. Os Estudos CrÃticos do Discurso (ECD) embasam teoricamente a pesquisa, especificamente a abordagem sociocognitiva de van Dijk (2006, 2008), que se configura na sua multidisciplinaridade, a partir das dimensÃes social, cognitiva e discursiva. Por meio da sociocogniÃÃo discursiva à que se torna viÃvel o perscrutar da estratÃgia de legitimaÃÃo da corrupÃÃo polÃtica dentre os textos produzidos na CÃmara Federal de Deputados do Brasil, grupo produtor dos discursos analisados. Ainda no aspecto teÃrico, propÃe-se uma articulaÃÃo entre a Teoria dos Blocos SemÃnticos de Carel e Ducrot (1997, 2001) e a sociocogniÃÃo, para assim fundamentar a metodologia de anÃlise, que investiga o discurso parlamentar de legitimaÃÃo da corrupÃÃo por meio da argumentaÃÃo dos seus sujeitos. O corpus de anÃlise à composto por pronunciamentos de deputados federais, entre os anos 2012 e 2013, sobre o âjulgamento do mensalÃoâ, evento emblemÃtico acerca da corrupÃÃo polÃtica que levou à condenaÃÃo lÃderes do Partido dos Trabalhadores (PT). Entende-se que, como grupo social, a CÃmara de Deputados e o PT, posicionam-se ideologicamente e que tal postura se apresenta no discurso produzido e compartilhado. A legitimaÃÃo discursiva da corrupÃÃo polÃtica produzida por um grupo social configura-se como abuso de poder. A sociocogniÃÃo se coloca no campo dos ECD porque investiga a ideologia de dominaÃÃo a partir da dimensÃo discursiva. A TBS fundamenta as categorias de anÃlise argumentativas necessÃrias ao perscrutar do discurso polÃtico, a partir dos enunciados elencados pelos sujeitos do discurso. Desta forma, entende-se que o desvelar de tais discursos de legitimaÃÃo corrobora contra uma forma mais sutil de opressÃo, a discursivo-ideolÃgica.
The âArgument in parliamentary discourse of legitimation of political corruptionâ, title of this thesis, aims to investigate the parliamentary discourse of legitimation of political corruption, focusing on the examination of how to configure the relationships between discourse, ideology and linguistic-discursive strategies. Perceived that the political corruption by discursive dimension, and not only by political science bias, in order to perceive that there is a discourse produced to legitimize this practice, and to identify the resources veiled that naturalize it. The Critical Discourse Studies (CDS) theoretically underlie the research, specifically the socio-cognitive approach to van Dijk (2006, 2008), which is configured in its multidisciplinary approach, from the dimensions social, cognitive and discursive. Through discursive socio-cognitive is that it becomes feasible to scrutinize the political corruption strategy of legitimation among the texts produced in the Chamber of Deputies of Brazil, producing group discourse analyzed. Although the theoretical aspect, we propose a link between the Theory of Semantic Blocks of Carel and Ducrot (1997, 2001) and sociocogniÃÃo, thus substantiate the analysis methodology, which investigates the parliamentary discourse legitimizing corruption by arguing the their subjects. The corpus of analysis consists of pronouncements of federal deputies, between the years 2012 and 2013, above âjulgamento do mensalÃoâ, flagship event on the political corruption that led the leaders of the Partido dos Trabalhadores (PT) to condemnation. It is understood that, as a social group, the Chamber of Deputies and the PT, position themselves ideologically and that such a stance is presented in the discourse produced and shared. The discursive legitimation of political corruption produced by a social group is characterized as abuse of power. The sociocogniÃÃo arises in the field of CDS because investigates the ideology of domination from the discursive dimension. The TBS based categories of argumentative analysis necessary to scrutinize the political discourse, from the statements listed by the subjects of discourse. Thus, it is understood that the unveiling of such discourses of legitimation corroborates against a more subtle form of oppression, discursive and ideological.
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Spolander, Rebecca. "The Fear of Mrs. Bates : The Use of Psychoanalytical Aspects, Anticipation and Retrospection in Robert Bloch’s Psycho." Thesis, Linnéuniversitetet, Institutionen för språk (SPR), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-70901.
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This essay focuses on psychoanalytical notions in Robert Bloch’s novel Psycho. The theoretical framework is based on Sigmund Freud’s theory of psychoanalysis. Slavoj Žižek’s idea that the house serves as a symbol of Freud’s concept of the Super-Ego, Ego and Id is presented and further developed. Moreover, it is exemplified how the idea of repression as a defense mechanism can be traced in the novel. It is then explained that repression is used as a tool for making the reader feel sympathy for Norman Bates. In addition, Wolfgang Iser’s reception theory is used to explain how Bloch uses gaps and pre-intentions in order to create anticipation and retrospection in the reader to produce suspense and horror. The intention is to prove that the attention to the psychological issues is what makes the monster of the novel more sympathetic and recognizable to us as readers. Thus, the result is that we position ourselves closer to the monster, which leaves us wondering if we could, due to our shared psychology, be monsters as well.
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Schweizer, Christian [Verfasser], and Immanuel [Akademischer Betreuer] Bloch. "Minimal instances for ℤ₂ lattice gauge theories and spin pumps / Christian Schweizer ; Betreuer: Immanuel Bloch." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1196529140/34.
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Laske, Michael. "Le K1 des courbes sur les corps globaux : conjecture de Bloch et noyaux sauvages." Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13861/document.
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Pour X une courbe sur un corps global k, lisse, projective et géométriquement connexe, nous déterminons la Q-structure du groupe de Quillen K1(X) : nous démontrons que dimQ K1(X) ? Q =2r, où r désigne le nombre de places archimédiennes de k (y compris le cas r = 0 pour un corps de fonctions). Cela con?rme une conjecture de Bloch annoncée dans les années 1980. Dans le langage de la K-théorie de Milnor, que nous dé?nissons pour les variétés algébriques via les groupes de Somekawa, le premier K-groupe spécial de Milnor SKM1 (X) est de torsion. Pour la preuve, nous développons une théorie des hauteurs applicable aux K-groupes de Milnor, et nous généralisons l’approche de base de facteurs de Bass-Tate. Une structure plus ?ne de SKM 1 (X) émerge en localisant le corps de base k, et une description explicite de la décomposition correspondante est donnée. En particulier, nous identi?ons un sous-groupe WKl(X):= ker (SKM 1 (X) ? Zl ? Lv SKM 1 (Xv) ? Zl) pour chaque entier rationnel l, nommé noyau sauvage, dont nous croyons qu’il est ?niFor a smooth projective geometrically connected curve X over a global ?eld k, we determine the Q-structure of its ?rst Quillen K-group K1(X) by showing that dimQ K1(X) ? Q =2r, where r denotes the number of archimedean places of k (including the case r = 0 for k a function ?eld). This con?rms a conjecture of Bloch. In the language of Milnor K-theory, which we de?ne for varieties via Somekawa groups, the ?rst special Milnor K-group SKM 1 (X) is torsion. For the proof, we develop a theory of heights applicable to Milnor K-groups, and generalize the factor basis approach of Bass-Tate. A ?ner structure of SKM 1 (X) emerges when localizing the ground ?eld k, and we give an explicit description of the resulting decomposition. In particular, we identify a potentially ?nite subgroup WKl(X):= ker (SKM 1 (X) ? Zl ? Lv SKM 1 (Xv) ? Zl) for each rational prime l, named wild kernel
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Rismal, Nina. "The ends of utopian thinking : Marx, Adorno, Bloch." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/273982.
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My dissertation is concerned with utopian thinking in Critical Theory. It examines the changing conceptions of radically different social orders held by the associates of the Frankfurt School. Its aim is to investigate utopian thinking as a theoretical tool of a system of thought that is oriented towards social transformation. To bring about social transformation was the explicit objective of the Frankfurt School. And yet, as my dissertation demonstrates, some of the key member of the Frankfurt School discarded precisely this utopian tool. This rejection of utopian thinking is one of the central – but also one of the most problematic – aspects of Critical Theory. It goes back to the writings of Marx himself and culminates in the works of Theodor W. Adorno, specifically in his ‘Utopieverbot’ (prohibition of envisaging a utopian society). I argue that this Utopieverbot facilitated the disappearance of utopian thinking in Critical Theory, and furthermore, that it brought this system of thought to a standstill. In addition to the dissolution of utopian thinking my dissertation examines also its potential resuscitation. The foremost defender of utopian thinking I investigate is Ernst Bloch, a critical theorist overshadowed by Adorno himself. Countering Adorno, Bloch posited utopian thinking not only as a possible but also as a necessary theoretical tool of Critical Theory. I argue that Bloch’s ideas can be valuable in resolving the aporia of utopian thinking in Critical Theory. While important in its own right, this aporia is highly significant due to the enormous influence it exerted on the death of utopia in Western political thought, which can be seen as one of the key factors contributing to the escalating social, political and economic regressions of our contemporary era. Understanding the reasons behind the emergence of death of utopia, as well as its possible resolutions, thus present questions that urgently need to be addressed.
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Mauthner, Ulrich [Verfasser], Herbert [Akademischer Betreuer] Spohn, and Stefan [Akademischer Betreuer] Teufel. "Space-adiabatic perturbation theory for Dirac-Bloch electrons / Ulrich Mauthner. Gutachter: Stefan Teufel. Betreuer: Herbert Spohn." München : Universitätsbibliothek der TU München, 2006. http://d-nb.info/1058138499/34.
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Hicks, Katrina. "The representation theory of some groups with blocks of defect group Câ†3 times Câ†3 in characteristic three." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239319.
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Imhof, Sebastian. "Mikroskopische Theorie der optischen Eigenschaften indirekter Halbleiter-Quantenfilme." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-81928.
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Indirekte Halbleiter, wie beispielsweise Silizium, zählen bei technischen Anwendungen zu den wichtigsten halbleitenden Materialien. Die indirekte Bandstruktur führt jedoch dazu, dass diese Materialien schlechte Lichtemitter sind. Die theoretische Beschreibung der optischen Eigenschaften dieser Materialien wurde in früheren Betrachtungen über phänomenologische Ansätze verfolgt. In dieser Arbeit wird eine mikroskopische Theorie, basierend auf den Heisenberg-Bewegungsgleichungen, entwickelt, um die Prozesse im Bereich der indirekten Energielücke zu beschreiben.
Nach Herleitung der relevanten Gleichungen wird im ersten Anwendungskapitel die Absorption und optische Verstärkung im thermischen Gleichgewicht diskutiert. Bei der Diskussion wird insbesondere auf den Unterschied zu direkten Halbleitern eingegangen. Es zeigt sich, dass sich die optische Verstärkung in indirekten Halbleitern fundamental von denen in direkten unterscheidet. Im Gegensatz zum direkten Halbleiter kann die maximale optische Verstärkung eines indirekten Übergangs die maximale Absorption um Größenordnungen übertreffen.
Im zweiten Anwendungsteil werden Nichtgleichgewichtsphänomene diskutiert. Durch starke optische Anregung kann eine hohe Elektronenkonzentration am Gamma-Punkt erzeugt werden. Da das globale Bandstrukturminimum aber am Rand der Brillouinzone liegt, verweilen die Elektronen nicht lange dort, sondern streuen in das Leitungsbandminimum. Dieser Prozess der sogenannten Intervalley-Streuung wird im Hinblick auf Gedächtniseffekte diskutiert. Nach dem Streuprozess der Elektronen besitzt das System eine Überschussenergie, die sich in einem Aufheizen der Ladungsträger zeigt. Das zweite Nichtgleichgewichtsphänomen ist das Abkühlen des Lochsystems, welches aufgrund der Trennung der Elektronen und Löcher in indirekten Halbleiter auch im Experiment getrennt untersucht werden kann. Mithilfe eines Experiment-Theorie-Vergleichs wird ein schneller Elektron-Loch-Streuprozess nachgewiesen, der dazu führt, dass in indirekten Halbleitern das Thermalisieren und Equilibrieren der Elektronen und Löcher auf der gleichen Zeitskala stattfindet.
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Semaan, Gaby. "Arab Americans Unveil the Building Blocks in the Construction of Our Cultural Identity." Bowling Green State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1187204165.
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Ordinola, David Martín Carbajal. "Sequência exata de Bloch-Wigner e K-teoria algébrica." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/55/55135/tde-09012017-162909/.
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A K-teoria algébrica é um ramo da álgebra que associa para cada anel com unidade R, uma sequência de grupos abelianos chamados os n-ésimos K-grupos de R. Em 1970, Daniel Quillen dá uma definição geral dos K-grupos de um anel qualquer R a partir da +-construção do espaço classificante BGL(R). Por outro lado, considerando R um anel comutativo, obtém-se também a definição dos K-grupos de Milnor KMn (R). Usando o produto dos K-grupos de Quillen e Milnor e suas estruturas anti-comutativas, definimos o seguinte homomorfismo tn : KMn (R) → Kn(R): Mostraremos nesta dissertação que se R é um anel local com ideal maximal m tal que R / m é um corpo infinito, então esse homomorfismo é um isomorfismo para 0 ≤ n ≤ 2. Em geral tn nem sempre é injetor ou sobrejetor. Por exemplo quando n = 3, sabe-se que t3 não é sobrejetor e definimos a parte indecomponível de K3(R) como sendo o grupo Kind3 (R) := coker (KM3 (R) → t3 K3(R)). Usando alguns resultados de homologia dos grupos lineares, nesta dissertação mostraremos a existência da sequência exata de Bloch-Wigner para corpos infinitos. Esta sequência dá uma descrição explícita da parte indecomponível do terceiro K-grupo de um corpo infinito. TEOREMA (Sequência exata de Bloch-Wigner). Seja F um corpo infinito e seja p(F) o grupo de pre-Bloch de F, isto é, o grupo quociente do grupo abeliano livre gerado pelos símbolos [a], a ∈ F×, pelo subgrupo gerado por elementos da forma [a] - [b] + [b/a] - [1-a-1 /1-b-1] + [1-a /1-b] com a, b ∈ F× - {1}, a /= b. Então temos a sequência exata TorZ1 (μ (F), μ (F)) ~ → Kind3 (F) → p(F) → (F× ⊗ ZFx)σ F×)σ → K2(F) → 0 onde (F× ⊗ ZF×)σ := (F×; ⊗ ZF×)/ e TorZ1 (μ (F); μ (F)) ~ é a única extensão não trivial de Z=2Z por TorZ1 (μ (F); μ (F)) se char(F) ≠ 2 e μ 2 ∞ (F) é finito e é TorZ1 (μ (F); μ (F)) caso contrário. O homomorfismo p(F) → (F× ⊗ ZF×) σ é definido por [a] → a ⊗ (1-a). O estudo da sequência exata de Bloch-Wigner é justificada pela relação entre o segundo e terceiro K-grupo de um corpo F.The algebraic K-theory is a branch of algebra that associates to any ring with unit R a sequence of abelian groups called n-th K-groups of R. In 1970, Daniel Quillen gave a general definition of K-groups of any ring R using the +-construction of the classifying space BGL(R). On the other hand, if we consider a commutative ring R, we can define the Milnors K-groups, KMn (R), of R. Using the product of the Quillen and Milnors K-groups and their anti-commutative structure, we define a natural homomorphism tn : KMn (R) → Kn(R): In this dissertation, we show that if R is a local ring with maximal ideal m such that R=m is infinite, then this map is an isomorphism for 0<= n<= 2. But in general tn is not injective nor is surjective. For example when n = 3, we know that t3 is not surjective and define the indecomposable part of K3(R) as the group Kind3 (R) := coker (KM3 (R) → t3 K3(R)). Using some results about the homology of linear groups, in this dissertation we will prove the Bloch-Wigner exact sequence over infinite fields. This exact sequence gives us a precise description of the indecomposable part of the third K-group of an infinite field. THEOREM (Bloch-Wigner exact sequence). Let F be an infinite field and let p(F) be the pre-Bloch group of F, that is, the quotient group of the free abelian group generated by symbols [a], a ∈ F× - [1}, by the subgroup generated by the elements of the form [a][b]+ b/a][ 1-a-1/1-b-1]+ [1-a/1-b] with a; b ∈ F×, a =/ b. Then we have the exact sequence TorZ1 (μ (F), μ (F)) ~ → Kind3 (F) → p(F) → (F× ⊗ ZF×)$sigma; → K2(F) → 0 where (F× ⊗ ZF×)σ := (F× ⊗ ZF×) / a &38855; b +b ⊗ a | a; b ∈ F× and TorZ1(μ(F);μ(F)) is the unique non trivial extension of Z=2Z by TorZ1 (μ (F); μ (F)) if char(F) =/ 2 and μ2 ∞ is finite and is TorZ1 (μ (F);μ (F)) otherwise. The homomorphism p(F) → (F×ZF×)%sigma; is defined by [a] → a ⊗ (1-a). As it is shown, the study of the Bloch-Wigner exact sequence is also justified by the relation between the second and third K-group of a field F.
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Barbosa, Enio Perez Rodrigues. "Planejamentos combinatórios construindo sistemas triplos de steiner." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tede/3074.
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Intuitively, the basic idea of Design Theory consists of a way to select subsets, also called blocks, of a finite set, so that some properties are satisfied. The more general case are the blocks designs. A PBD is an ordered pair (S;B), where S is a finite set of symbols, and B is a collection of subsets of S called blocks, such that each pair of distinct elements of S occur together in exactly one block of B. A Steiner Triple System is a particular case of a PBD, where every block has size only 3, being called triples. The main focus is in building technology systems. By resolvability is discussed as a Steiner Triple Systems is resolvable, and when it is not resolvable. This theory has several applications, eg, embeddings and even problems related to computational complexity.
Intuitivamente, a idéia básica de um Planejamento Combinatório consiste em uma maneira de selecionar subconjuntos, também chamados de blocos, de um conjunto finito, de modo que algumas propriedades especificadas sejam satisfeitas. O caso mais geral são os planejamentos balanceados. Um PBD é um par ordenado (S;B), onde S é um conjunto finito de símbolos, e B é uma coleção de subconjuntos de S chamados blocos, tais que cada par de elementos distintos de S ocorrem juntos em exatamente um bloco de B. Um Sistema Triplo de Steiner é um caso particular de um PBD, em que todos os blocos tem tamanho único 3, sendo chamados de triplas. O foco principal está nas técnicas de construção dos sistemas. Por meio da resolubilidade se discute quando um Sistema Triplo de Steiner é resolvível e quando não é resolvível. Esta teoria possui várias aplicações, por exemplo: imersões e até mesmo problemas relacionados à complexidade computacional.
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Dalton, Karen Sonya Helen. "Pulsed field studies of magnetotransport in semiconductor heterostructures." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325936.
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DeBono, Daniela. "In search of the building blocks of a human rights culture : lessons from the treatment of irregular immigrants in Malta." Thesis, University of Sussex, 2012. http://sro.sussex.ac.uk/id/eprint/38668/.
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The treatment of irregular migrants in Malta is problematic from a human rights perspective, for it contravenes the principle of universalism that is intrinsic to human rights philosophy. This study investigates this treatment. Crucially, it identifies four elements of political practice in the absence of which it is contended a human rights culture cannot flourish, as well as underlying patterns in Maltese political culture which contravene these four elements. Its ultimate aim is to propose meaningful, effective and long-lasting human-rights-compliant solutions to the treatment of irregular immigrants in Malta. Based on a reading of foundational documents of the modern human rights movement, especially the Universal Declaration of Human Rights, the thesis posits that human rights should be ‘located' between the political and the cultural. The four basic principles of human rights identified as framing the optimal political conditions for the nurturing of a human rights culture are related to dignity, a cosmopolitan orientation, democratic practice and a commitment to equality. This concept of a human rights culture is innovatively used as an analytical tool for examining Maltese responses to irregular migration. This is done in a two-way manner, with the examination of practice enriching the identified theoretical framework, and the theoretical framework then guiding the search for possible new human-rights-consistent policy directions which Malta could take. Drawing on a range of ethnographic methods, including in-depth interviews and participant observation, this study brings to light the difficulties of putting into practice human rights principles within an already established local culture grappling with its own ghosts like occupations and colonial experiences. Although resistance to change is often difficult to identify since it is shrouded in ‘modern' language, hidden under security arguments or bureaucratic explanations. Interviews and a range of documents illustrate the multi-layered misconceptions, stereotypes and fear that play out among the Maltese.
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Vinches, Marc. "Application de l'analyse structurale, de la geostatistique et de la theorie des blocs-cles a l'etude de la stabilite des massifs rocheux fractures." Paris, ENMP, 1988. http://www.theses.fr/1988ENMP0136.
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Matsui, Masafuyu. "Role of Interchain Interaction in Determining the Band Gap of Trigonal Selenium: A Density Functional Theory Study with a Linear Combination of Bloch Orbitals." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/195940.
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Brito, Frederico Borges de. "Um estudo sobre processos de descoerência em qubits de estado sólido." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277286.
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Orientador: Amir Ordacgi CaldeiraTese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
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Resumo: Esta tese teve como objetivo estudar processos de perda de coerência quântica, chamados de descoerência, em sistemas de matéria condensada eleitos pela literatura como possíveis implementações do bit quântico (qubit). Esta perda de coerência quântica ocorre devido ao inevitável acoplamento do sistema de interesse com o seu ambiente. Como os estados de superposição quântica são a chave para a realização de operações baseadas na lógica quântica, tem-se que tais processos limitam ou até mesmo impedem o uso de determinados sistemas na esperada realização física do computador quântico. Os sistemas de matéria condensada padecem de uma dificuldade maior para se isolar o qubit do seu ambiente, o que acarreta, em geral, na observação de tempos de coerência piores do que os encontrados em seus concorrentes. Por outro lado, a possibilidade de construção de vários qubits acoplados e de manipulação de cada um de modo individual, usando-se técnicas convencionais de engenharia, têm impulsionado esforços nestes tipos de dispositivos. Os sistemas abordados na tese foram: qubits supercondutores contendo junções Josephson; e qubits de pontos quânticos. Para a investigação completa do primeiro tipo tivemos que desenvolver o modelo Caldeira-Leggett para o caso de várias fontes de dissipação acopladas ao qubit. Com a prescrição apresentada aqui, pudemos determinar o número de banhos de osciladores necessários para a correta descrição das fontes, e verificar que as taxas totais de relaxação e de descoerência não são necessariamente as somas das taxas devido a cada fonte individualmente. Além disso, pudemos aplicar o formalismo desenvolvido no estudo de um qubit de uxo em investigação. Para o sistema de pontos quânticos seguimos a linha de determinação do banho efetivo visto pelo grau de liberdade de spin do elétron aprisionado no ponto quântico. Determinada a função espectral efetiva, pudemos encontrar soluções analíticas para a dinâmica do valor esperado para cada uma das componentes de spin s x,y,z. o que permitiu uma análise completa dos efeitos de cada parâmetro físico do sistema. Em ambos os casos, fomos capazes de indicar os melhores regimes de operação de cada qubit, e dar estimativas dos tempos de relaxação e de descoerência
Abstract: The purpose of this thesis was to study the process of loss of quantum coherence, named decoherence, in condensed matter systems cited in the literature as possible candidates for the implementation of a quantum bit (qubit). Decoherence occurs due to the inevitable coupling of the system of interest to its environment. Once the quantum superposition states are the key to perform operations based on quantum logic, these processes limit, or even hinder, the utilization of some of those systems in the physical realization of the quantum computer. Relatively to its competitors, condensed matter systems usually present a higher degree of difficulty as one tries to minimize the coupling between the qubit and its environment, which, generally, worsens its coherence time observations. On the other hand, these devices present advantages which stimulates its study, such as: the possibility of construction of several coupled qubits and the possibility of manipulating each one individually, using conventional engineering techniques. The systems studied in this thesis were: superconducting qubits with Josephson junctions; and electronic spins quantum dots. Aiming at a complete investigation of the first system, we developed the Caldeira-Leggett model for the case of several dissipation sources coupled to the qubit. With the prescription presented here, we determine the number of oscillator baths needed to the correct description of the noise sources, and verify that the total relaxation and decoherence rates are not necessarily the sum of the individual rates relative to each source. Moreover, we applied this formalism to the study of a ux qubit currently under investigation. For the quantum dot qubits, we employed the effective bath approach to treat the dynamics of the spin of the electron localized in the quantum dot. As a result, we found analytical solutions for the dynamics of the average value of each one of the spin components s x,y,z . In both cases, we indicated the best operational regime of each qubit and gave estimates of the relaxation and decoherence times
Doutorado
Física da Matéria Condensada
Doutor em Ciências
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Ito, William Hideki. "Contribuição ao estudo de instabilidade em túneis não revestidos da estrada de ferro Vitória-Minas através da teoria dos blocos-chave e caracterização da rocha através de ensaios laboratoriais e de campo." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3145/tde-23062016-163256/.
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No país existem inúmeras estruturas e obras civis que estão em operação a dezenas de anos e necessitam de monitoramento periódico devido a sua importância. Por este motivo, a dissertação apresenta um caso de um túnel antigo com problema de queda de bloco e visa instigar novas pesquisas e aumentar o conhecimento sobre o tema. Foram realizadas inspeções em campo em alguns túneis não revestidos da Estrada de Ferro Vitória-Minas (EFVM), bem como os ensaios em laboratório e in situ realizados nas amostras e no maciço rochoso para caracterizar o problema. Para o estudo foi escolhido o túnel Monte Seco Linha 1 e Linha 2 nos quais foram realizadas sondagens rotativas inclinadas e orientadas próximas ao eixo para investigação dos planos de descontinuidade. Os conceitos da Teoria dos Blocos-Chave foram aplicados às famílias de descontinuidades encontradas nos Túneis Monte Seco L1 e L2 para identificar os possíveis blocos instáveis formados pelas escavações. Para obtenção dos parâmetros geotécnicos de resistência e deformabilidade foram realizados ensaios de compressão uniaxial instrumentados com strain gages. A resistência a tração foi obtida através de Ensaio de Compressão Diametral (ECD). No ensaio de campo foi utilizado o Martelo de Schmidt para avaliação da rocha in situ. Através da análise dos dados foi possível distinguir setores cuja ocorrência de queda de blocos são maiores e a classe do maciço rochoso de acordo com a proposta de Bieniawski.In the country there are numerous structures and civil works that are in operation for tens of years and require periodic monitoring due to its importance. For this reason, the dissertation presents a case of an old tunnel with block fall problem and aims to instigate new research and increase knowledge on the subject. Inspections were carried out in the field in some tunnels uncovered of the Railroad Vitória-Minas (EFVM) and testing in the laboratory and in situ carried out on the samples and the rock mass to characterize the problem. To study the tunnel Monte Seco Line 1 and Line 2 of which were held rotary polls inclined and oriented close to the axis to investigate the discontinuation plans was chosen. The concepts of the Key Block Theory were applied to the families of discontinuities found in Tunnels Monte Seco L1 and L2 to identify potential unstable blocks formed by the excavations. To obtain the geotechnical parameters of strength and deformability were performed uniaxial compression tests instrumented with strain gages. The tensile strength was obtained by diametral compression test (ECD). A field test was used to evaluate Schmidt hammer rock in situ. Through the analysis of the data was possible to distinguish sectors whose occurrence of falling blocks are larger and the rock mass class in accordance with the proposal of Bieniawski.
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Ladeira, Wagner Júnior. "Integração produtiva no Mercosul : uma análise dos fatores que interferem no processo de internacionalização da produção de firmas brasileiras." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/37184.
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A integração produtiva com o MERCOSUL, nos últimos, anos tem recebido uma atenção especial na agenda de políticas internacionais do governo brasileiro. Esse fato pode ser explicado pelo número crescente de empresas brasileiras que procuram integrar sua produção com empresas da Argentina, Uruguai, Paraguai e Venezuela. Dentro desse contexto, o objetivo geral desta tese é analisar as relações funcionais dos fatores relacionados à natureza da firma e à formação de blocos econômicos que interferem nas estratégias de integração produtiva no MERCOSUL. Para entender o objeto de estudo desta tese, foi desenvolvida uma base teórica com foco nas abordagens epistemológicas das estratégias de integração produtiva, na teoria da firma e na formação de blocos econômicos. Logo após, foi apresentado um modelo teórico, fundamentado em hipóteses, as quais são baseadas na abordagem teórica da firma e nos estudos de formação de blocos econômicos. A pesquisa realizada utilizou uma abordagem mista, dividida em três etapas. Na primeira etapa, foram coletados 137 questionários, e serviu para a purificação do instrumento de Coleta de Dados. Na segunda etapa, com a coleta final de 516 respondentes, foi feita a análise dos dados quantitativos. Para isso, utilizou-se a Modelagem de Equações Estruturais (MEE), avaliando individualmente os construtos e discutindo as relações do modelo estrutural e suas hipóteses. Logo após a interpretação dos dados quantitativos, utilizou-se a técnica de análise de conteúdo para interpretar as relações validadas ou não na MEE. Nessa fase, foram realizadas 11 entrevistas semiestruturadas, que tiveram como objetivo analisar os achados teóricos e empíricos do trabalho. Após a validação e análise do modelo, foram feitas as considerações finais dos achados desta pesquisa. Constatou-se que a integração produtiva no MERCOSUL trata-se de um tema evidente, especialmente pelas complexas relações existentes nos fatores que antecedem (influenciam) sua prática. Como pode ser depreendida na base teórica e na análise dos resultados, a materialização dos benefícios da integração envolve um profundo processo de reorganização estratégica da estrutura produtiva das empresas e dos países-membros do MERCOSUL. Desse modo, o presente estudo pretendeu contribuir para a discussão dos estudos de internacionalização da produção em blocos econômicos, incentivando futuros debates que venham a contribuir para a evolução desse campo.In recent years, the productive integration with Mercosur has received special attention in the international political agenda of the Brazilian government. This fact can be explained by the increasing number of Brazilian companies that seek to integrate their production with companies in Argentina, Uruguay, Paraguay and Venezuela. Within this context the overall aim of this thesis is to analyze the functional relationships of the factors related to the nature of the firm and the formation of economic blocks that interfere with productive integration strategies in MERCOSUR. To understand the subject matter of this thesis, it was developed a theoretical basis with a focus on epistemological approaches of integration strategies in production, the theory of the firm and the formation of economic blocs. Soon after, it was presented a theoretical model based on assumptions related to the theoretical approach of the firm and in studies about the formation of economic blocs. The survey used a mixed approach, divided into three steps. In the first stage 137 questionnaires were collected. This first stage was the cleansing function of the instrument Data Collection. In the second stage, with the final collection of 516 respondents, it was analyzed the quantitative data. For this matter we used the Structural Equation Modeling (MEE), evaluating the individual constructs and discussing the relationships of the structural model and its assumptions. Soon after the interpretation of quantitative data, we used the technique of content analysis to interpret the relationships validated in the MEE. This phase was conducted by eleven semi-structured interviews aimed to analyze the findings of the theoretical and empirical work. After validation and analysis of the model, it was made the final considerations of the findings of this research. It was found that the productive integration in MERCOSUR is clearly an issue, especially the complex relationships that exist in the factors leading (influencing) their practice. As can be deduced from the theoretical basis and analysis of results, the realization of the benefits of integration involves a thorough process of strategic reorganization of production structures and member countries of MERCOSUR. Thus, this study aimed to contribute to the discussion of studies about the internationalization of production blocs, encouraging future research which may contribute to the evolution of this field.
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Francisco, Bruno Mattiello. "Um modelo de leilões com conteúdo local: análise e modelagem dos leilões de concessão de blocos exploratórios de petróleo e gás promovidos pela ANP no Brasil." reponame:Repositório Institucional do FGV, 2014. http://hdl.handle.net/10438/14009.
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Brazil’s oil auctions use an equation to form a score that defines the winner. Each company or consortium interested in the oil block must bid in three attributes: Signature Bonus (BA), Minimum Exploration Program (PEM) and Local Content (CL). Each of these attributes receives a weight in the equation and bidder’s final score also depends on the others companies bid. Although oil auctions have being widely studied in the economy the multi-attribute score auction is still poorly analyzed specially as a mechanism of mining rights allocation. The present work highlights the insertion of the local content as an attribute which transforms the auction structure from what could be a first price auction to a multi-attribute score auction. Through the project’s costs curve is demonstrated how the local content is related to another important score attribute that is the signature bonus. To better understand the insertion of the local content attribute we have created three cases of hypothetical auctions. We also have fixed the minimum exploration program and made some simplifications in order to build those cases. In the first scenario (Sem CL), the structure comes down to a first-price auction, where only the BA attribute defines the auction winner. In the second scenario (CLO=CLR), where the local content does impact the final score, the bidder is obligated to realize the local content as was bid. The last scenario is the complete case (Com Multa) which allows the bidder to failure the local content bid when paying the penalty represents an economic gain to the company. Taking those cases into consideration we have verified that, although the company’s revenue and the allocation efficiency don’t vary, the government revenue drops significantly when the local content is introduced as an attribute of score auctions.
Os leilões para concessão de blocos de petróleo no Brasil utilizam uma equação para formar a pontuação que define o vencedor. Cada participante deve submeter ao leiloeiro um lance composto por três atributos: Bônus de Assinatura (BA), Programa Exploratório Mínimo (PEM) e Conteúdo Local (CL). Cada atributo possui um peso na equação e a nota final de cada participante também depende dos lances ofertados pelos outros participantes. Apesar de leilões de petróleo serem muito estudados na economia, o leilão multi-atributos, do tipo máxima pontuação, ainda é pouco analisado, principalmente como mecanismo de alocação de direitos minerários. Este trabalho destaca a inserção do CL como atributo que transforma a estrutura, do que poderia ser um leilão simples de primeiro preço, em um leilão multi-atributos de máxima pontuação. Demonstra-se como o CL, através da curva de custos do projeto, está relacionado também ao Bônus de Assinatura, outro importante atributo da equação. Para compreender o impacto do fenômeno da inserção do CL, foram criados três casos de leilões hipotéticos, onde, dentre outras simplificações, o programa exploratório mínimo foi fixado para todas as empresas envolvidas. No caso base (Sem CL), simula-se a estrutura de um leilão de primeiro preço, onde apenas o BA define o vencedor do leilão. Já no caso forçado (CLO=CLR), há inserção do atributo CL, sendo o participante obrigado a cumprir o CL ofertado. Por fim, o caso completo (Com Multa) permite que o participante preveja a aplicação de multa por descumprimento do CL ofertado e, caso haja benefício econômico, descumpra efetivamente o CL ofertado. Considerando estes casos, argumenta-se que, apesar do o lucro das empresas e a eficiência do leilão não serem alterados, a inclusão do conteúdo local na estrutura do leilão pode ter reflexos consideráveis na receita do governo.
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Podzimski, Reinold Ephraim [Verfasser]. "Shift currents in bulk GaAs and GaAs quantum wells analyzed by a combined approach of k.p perturbation theory and the semiconductor Bloch equations / Reinold Ephraim Podzimski." Paderborn : Universitätsbibliothek, 2016. http://d-nb.info/1123126739/34.
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Huang, Fan. "Allocation des ressources fondée sur la qualité du canal pour la voie descendante des systèmes LTE." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS250/document.
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La recherche effectuée dans cette thèse a pour cadre les réseaux radio privés dédiés aux forces de sécurité civile. En effet, doté actuellement d’un service bande étroite, ils doivent évoluer pour faire face à de nouveaux besoins comme la vidéo ou le multimédia. L’objectif est donc d’adapter la technologie LTE aux contraintes et propriétés de ces réseaux particulier. Ainsi, le nombre d’utilisateurs est limité mais le service doit toujours être disponible et des priorités peuvent être mises en œuvre.Dans ce contexte, l’allocation des ressources de communication est un problème important avec des prérequis différents des réseaux d’opérateurs. Notre conception d’algorithmes d’allocation a donc été menée avec deux objectifs principaux : maximiser l'efficacité du spectre et servir équitablement les utilisateurs au lieu de maximiser le débit global du réseau.Cette thèse propose des nouvelles stratégies de l’allocation des blocs de ressources (RB) dans les systèmes LTE sur le lien descendant. Au contraire des algorithmes classiques d'allocation des ressources qui se basent sur la capacité de RB déjà estimée, nos stratégies d’allocation des RB cherchent à améliorer le débit utilisateur, en utilisant la coopération à base de Beamforming et les modèles de la théorie des jeux.1. L’interférence inter-cellulaire est le principal problème des systèmes OFDMA. Grâce aux antennes MIMO (Multiple-Input-Multiple-Output), la technique de Beamforming améliore le signal reçu afin d'augmenter le SINR (Signal-to-Interference-plus-Noise-Ratio), mais le signal amélioré peut également influencer l’interférence inter-cellulaire dans les cellules voisines. Dans les méthodes traditionnelles, le contrôleur alloue les RBs aux UEs (User Equipement) en fonction de la capacité des RB et d'autres paramètres, le système applique alors la technique de Beamforming aux équipements utilisateurs choisis. Après la formation des faisceaux, la capacité des RB varie mais l'ordonnanceur conserve la même allocation. Au contraire, notre système alloue les RBs et choisit les vecteurs de Beamforming conjointement pour améliorer les performances de la technique de Beamforming. Il accroît le débit moyen en augmentant la capacité moyenne du RB. Comme plusieurs paramètres sont pris en compte, la complexité augmente exponentiellement aussi. Dans cette thèse, nous avons développé une méthode itérative pour réduire la complexité. Notamment, elle améliore de plus de 10% le débit des utilisateurs en bord de la cellule.2. Contrairement aux performances des algorithmes qui maximisent le débit global du réseau, les approches d’allocation de ressources à base de théorie des jeux maximisent la fonction d'utilité des UE du point de vue économique. Si le modèle a une solution NBS (Nash Bargaining Solution) il offre une solution optimale de Pareto de la fonction d'utilité. L’allocation traditionnelle est d'optimiser l'allocation de sous-porteuses à chaque intervalle de temps, mais dans le système OFDMA, les sous-porteuses sont formées de RBs dans le temps. Nous proposons une approche RB NBS, qui est plus efficace que les schémas existants. Nous analysons les canaux de fast-fading et les comparons sans l'influence de l’atténuation. En raison de la grande atténuation de signal en bordure de la cellule, l’utilisateur a toujours des RB de plus faible capacité que celui au centre de la cellule. Notre idée est d'ajouter un facteur de compensation pour combattre l'influence de la perte de propagation. Les facteurs de compensation sont soigneusement choisis afin de maximiser la fonction NBS. Cependant, le calcul de ces facteurs a une grande complexité et nous développons quatre solutions approchées qui donnent les mêmes performances avec une bonne précision. L'évaluation des performances de notre approche confirme que notre méthode et ses solutions approchées sont capables de partager équitablement les ressources sur toute la celluleThis research takes place in the context of Private Mobile Radio networks evolution which aims at designing a new LTE based PMR technology dedicated to public security services. As the frequency bands dedicated to this service is scarce and the need of public safety forces is different, we have revisited the Resource Allocation problem in this thesis with two main objectives: designing new allocation algorithms which outperform the spectrum efficiency and serving fairly the users instead of maximizing the global network throughput.This thesis proposes new Resource Block (RB) allocation strategies in LTE downlink systems. Instead of the well-known resource allocation algorithms, which work on the condition that the RB capacity is already estimated, our RB allocation schemes can improve the potential of the channel capacity, using Beamforming cooperation and game-theoretical problems1. With the MIMO (Multiple-Input-Multiple-output) antennas, the Beamforming technique improves the received signal in order to increase the SINR (Signal-to-Interference-plus-Noise-Ratio), but the improved signal may also influence the inter-cell interference in the neighbouring cells. As inter-cell interference is the main interference in the OFDMA system, a smart scheduling can choose UEs (User Equipment) in adjacent cells to control interference increment caused by Beamforming.In traditional methods, the scheduler allocates RBs to UEs depending on the RB capacities and other parameters, the system then applies the Beamforming technique to these chosen UEs. After the Beamforming, the RB capacity varies but the scheduler keeps the same allocation.Our scheme allocates the RBs and chooses Beamforming vectors at the same time to enhance the performance of the Beamforming technique. It increases the average throughput by increasing the RB’s average capacity. Because more parameters are taken into account, the complexity also increases exponentially. In the thesis we find an iterative method to reduce the complexity. From the simulations, our iterative method also has good performance and improves more than 10% of throughput on the cell edge.2. In contrast to the performance first algorithms, game theoretic allocation schemes maximize the UEs’ utility function from the economical point of view. The NBS (Nash Bargaining Solution) offers a Pareto optimal solution for the utility function.The traditional NBS allocation in an OFDMA system is to optimize the subcarrier allocation at each time slot, but in the OFDMA system, the subcarriers are composed of Resource Blocks (RB) in time series. We propose an RB NBS approach, which is more efficient than the existing subcarrier NBS allocation scheme.We analyze the fast-fading channels and compare them without the path-loss influence. Because of the great path-loss in cell edge, the edge UE always has lower RB capacity than the cell center UE. Our idea is to bring in a compensating factor to overcome this path-loss influence, and the compensating factors are carefully chosen to maximize the NBS function. However, the computation of these factors has a high complexity and we develop four approximated solutions which give same performance and accuracy. The performance evaluation confirms that our method and its approximated solutions are able to spread resources fairly over the entire cell
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Laurent, Arthur. "Autour des nombres de Tamagawa." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00858435.
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Les nombres de Tamagawa des courbes elliptiques apparaissent dans la formulation de la conjecture de Birch et Swinnerton-Dyer comme certains facteurs locaux. Bloch et Kato (1990) ont trouvé une vaste généralisation de cette définition classique en termes de la théorie de Hodge p-adique. Ils ont associé un nombre de Tamagawa Tam(T) à tout réseau T de représentations p-adiques de de Rham au sens de J.-M. Fontaine. Ces nombres interviennent dans les conjectures de Bloch et Kato sur les valeurs spéciales des fonctions L des motifs.J.-M. Fontaine et B.Perrin-Riou ont formulé une conjecture reliant Tam(T) et le nombre de Tamagawa Tam(T*}(1)) de la représentation duale. Cette conjecture est connue pour les représentations cristallines ce qui permet de calculer explicitement les nombres de Tamagawa des représentations cristallines dont les poids de Hodge-Tate sont tous positifs. En revanche, dans la plupart des autres cas, nous n'avons pas de méthode de calcul explicite. Cette thèse a pour but de donner un encadrement des nombres de Tamagawa des représentations absolument cristallines le long de la tour cyclotomique sans hypothèses supplémentaires sur les poids de Hodge-Tate. Le premier chapitre de cette thèse est dédié à des rappels sur la théorie de Hodge p-adique, la classification de Fontaine des représentations p-adique de corps locaux via la théorie des (phi, Gamma)-modules, sur la cohomologie galoisienne, sur les modules de Wach ou sur la cohomologie d'Iwasawa. Le second chapitre est dédié à l'exponentielle de Bloch and Kato. Seront rappelées sa définition et sa construction de l'exponentielle de Bloch and Kato en termes de (phi, Gamma)-modules faite par D.Benois. Cette dernière construction permet de généraliser deux résultats de D.Benois et L.Berger qui relient l'exponentielle aux modules de Wach et qui permet de décrire des objets qui apparaissent naturellement dans l'étude des nombres de Tamagawa. Le dernier chapitre est le cœur de cette thèse. Nous commencerons en définissant les nombres de Tamagawa Tam(T) et en donnant certaines propriétés et résultats déjà connus. Nous énonçons ensuite le théorème final qui donne un encadrement des nombres de Tamagawa d'une représentation absolument cristalline V. Y sont également donnés certains cas d'égalité qui permettent de retrouver des formules connues --- lorsque V est positive ou lorsqu'elle provient d'une courbe elliptique et plus généralement d'un groupe formel de dimension 1 et de hauteur 2. Pour prouver ces résultats, nous écrivons les nombres de Tamagawa sous forme d'un indice généralisé dans lequel apparaissent les objets étudiés dans le chapitre précédent. La thèse se termine avec l'étude de plusieurs cas particuliers qui permettent de retrouver des résultats déjà connus.
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Chinello, Gianmarco. "Représentations l-modulaires des groupes p-adiques : décomposition en blocs de la catégorie des représentations lisses de GL(m,D), groupe métaplectique et représentation de Weil." Thesis, Versailles-St Quentin en Yvelines, 2015. http://www.theses.fr/2015VERS045V/document.
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Cette thèse traite deux problèmes concernant la théorie des représentations `-modulairesd’un groupe p-adique. Soit F un corps local non archimédien de caractéristique résiduelle pdifférente de `. Dans la première partie, on étudie la décomposition en blocs de la catégoriedes représentations lisses `-modulaires de GL(n; F) et de ses formes intérieures. On veutramener la description d’un bloc de niveau positif à celle d’un bloc de niveau 0 (d’un autregroupe du même type) en cherchant des équivalences de catégories. En utilisant la théoriedes types de Bushnell-Kutzko dans le cas modulaire et un théorème de la théorie descatégories, on se ramene à trouver un isomorphisme entre deux algèbres d’entrelacement.La preuve de l’existence d’un tel isomorphisme n’est pas complète car elle repose sur uneconjecture qu’on énonce et qui est prouvée pour plusieurs cas. Dans une deuxième partieon généralise la construction du groupe métaplectique et de la représentation de Weil dansle cas des représentations sur un anneau intègre. On construit une extension centrale dugroupe symplectique sur F par le groupe multiplicatif d’un anneau intègre et on prouvequ’il satisfait les mêmes propriétés que dans le cas des représentations complexesThis thesis focuses on two problems on `-modular representation theory of p-adic groups.Let F be a non-archimedean local field of residue characteristic p different from `. In thefirst part, we study block decomposition of the category of smooth modular representationsof GL(n; F) and its inner forms.We want to reduce the description of a positive-levelblock to the description of a 0-level block (of a similar group) seeking equivalences of categories.Using the type theory of Bushnell-Kutzko in the modular case and a theorem ofcategory theory, we reduce the problem to find an isomorphism between two intertwiningalgebras. The proof of the existence of such an isomorphism is not complete because itrelies on a conjecture that we state and we prove for several cases. In the second part wegeneralize the construction of metaplectic group and Weil representation in the case ofrepresentations over un integral domain. We define a central extension of the symplecticgroup over F by the multiplicative group of an integral domain. We prove that it satisfiesthe same properties as in the complex case
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Giuliani, Chiara. "Alteration of ocean waves by periodic submerged structures for renewable energy extraction." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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Questa tesi si concentra sul comportamento di strutture immerse e sulla loro interazione con fenomeni ondosi oceanici allo scopo di modificarne l’ampiezza in superficie. Si suppone che queste strutture siano disposte sul fondale marino secondo schemi geometrici ricorrenti, per esempio lenti. Opportune disposizioni strutturali possono indurre un’interferenza costruttiva sulle onde di superficie, le quali presentano tipicamente un carattere pseudo-periodico nel tempo e nello spazio aumentandone così l’ampiezza.
Noto che l’energia delle onde di superficie è proporzionale alla loro ampiezza, i risultati proposti in questa ricerca possono essere utilizzati per migliorare, in maniera del tutto sostenibile, l’efficienza dei dispositivi che sfruttano il moto ondoso per l’estrazione di energia rinnovabile, anche noti come energy harvesters. Per questi ultimi infatti l’efficienza della conversione dell’energia dipende dalla variazione altimetrica fra la cresta e il ventre dell’onda.
Nello studio del problema, si considereranno le equazioni classiche di Navier-Stokes applicate al caso di fondali medio bassi (shallow waters). Successivamente teorie complesse per lo studio di sistemi periodici (già utilizzate in altri campi come la fisica quantistica e l’elettromagnetismo), verranno applicate per descrivere l’interazione tra le onde e il fondale periodico. Tale formulazione consentirà di progettare le strutture sul fondale capaci ottimizzare l’ampiezza dell’onda rispetto al caso di fondale indisturbato.
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Gruber, Michael. "Nichtkommutative Blochtheorie." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 1998. http://dx.doi.org/10.18452/14360.
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In der vorliegenden Arbeit "Nichtkommutative Blochtheorie" beschäftigen wir uns mit der Spektraltheorie bestimmter Klassen von Hilbertraumoperatoren, den elliptischen Operatoren auf Darstellungsräumen von Hilbert-C*-Moduln. Die auftretenden C*-Algebren kodieren dabei Symmetrieeigenschaften der entsprechenden Operatoren.Für kommutative Symmetrien ist die Blochtheorie ein geeignetes Hilfsmittel. Wir schildern diese Methode zunächst in einem geometrischen Kontext, der allgemein genug ist, um die bekannten Ergebnisse über die Abwesenheit singulärstetigen Spektrums im Hinblick auf physikalische Anwendungen zu erweitern. Wir lassen uns dann durch eine Neuinterpretation der Blochtheorie aus einem nichtkommutativen Blickwinkel inspirieren zur Entwicklung einer nichtkommutativen Blochtheorie. Dabei werden bestimmte Eigenschaften von C*-Algebren verknüpft mit Eigenschaften des Spektrums elliptischer Operatoren. Diese Blochtheorie für Hilbert-C*-Moduln erlaubt es, verschiedene bekannte Resultate aus dem Bereich kommutativer (diskreter und kontinuierlicher) Geometrien mit nichtkommutativen Symmetrien in einem neuen gemeinsamen Rahmen zusammenzufassen, der Raum läßt für Modelle nichtkommutativer Geometrien mit nichtkommutativen Symmetrien. Wichtigstes Beispiel für die behandelte Klasse von Operatoren in der mathematischen Physik sind die Schrödingeroperatoren mit periodischem Magnetfeld und Potential. Wir ordnen sie in den Rahmen kommutativer und nichtkommutativer Blochtheorie ein und wenden die zuvor bereitgestellten Methoden an.In this doctoral thesis "Nichtkommutative Blochtheorie'' (non-commutative Bloch theory) we investigate the spectral theory of a certain class of operators on Hilbert space: the elliptic operators associated with representations of Hilbert C*-modules. The C*-algebras that arise encode symmetry properties of the corresponding operators. For commutative symmetries Bloch theory is a proper tool. We describe this method in a geometric context which is general enough to extend known results about absence of singular continuous spectrum in view of physical applications. Then --- inspired by a new interpretation of Bloch theory from a non-commutative point of view --- we develop a non-commutative Bloch theory. Here certain properties of C*-algebras get linked to spectral properties of elliptic operators. This Bloch theory for Hilbert \CS-modules allows to unite, in a new common framework, several known results from the field of commutative (discrete and continuous) geometries having non-commutative symmetries; this leaves ample room for models of non-commutative geometries having non-commutative symmetries. In mathematical physics, the most important example for the class of operators considered is given by the Schrödinger operators with periodic magnetic field and potential. We place them into the framework of commutative and non-commutative Bloch theory and apply the methods developed before.
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Hossain, A. N. M. Shahriyar. "Metamaterials: 3-D Homogenization and Dynamic Beam Steering." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1574430585435814.
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Hejtmánek, Michal. "Užití genetického programování v návrhu digitálních obvodů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-235950.
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The goal of this work was the study of evolutionary algorithms and utilization of them for digital circuit design. Especially, a genetic programming and its different manipulation with building blocks is mentioned in contrast to a genetic algorithm. On the basis of this approach, I created and tested a hybrid method of electronic circuit design. This method uses spread schemes according to the genetic algorithm for the pattern problems witch are solved by the genetic programming. The method is more successful and have faster convergence to a solution in difficult electronic circuits design than a common algorithm of the genetic programming.
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Nemati, Navid. "Theorie macroscopique de propagation du son dans les milieux poreux 'à structure rigide permettant la dispersion spatiale: principe et validation." Phd thesis, Université du Maine, 2012. http://tel.archives-ouvertes.fr/tel-00848603.
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Ce travail présente et valide une théorie nonlocale nouvelle et généralisée, de la propagation acoustique dans les milieux poreux à structure rigide, saturés par un fluide viscothermique. Cette théorie linéaire permet de dépasser les limites de la théorie classique basée sur la théorie de l'homogénéisation. Elle prend en compte non seulement les phénomènes de dispersion temporelle, mais aussi ceux de dispersion spatiale. Dans le cadre de la nouvelle approche, une nouvelle procédure d'homogénéisation est proposée, qui permet de trouver les propriétés acoustiques à l'échelle macroscopique, en résolvant deux problèmes d'action-réponse indépendants, posés à l'échelle microscopique de Navier-Stokes-Fourier. Contrairement à la méthode classique d'homogénéisation, aucune contrainte de séparation d'échelle n'est introduite. En l'absence de structure solide, la procédure redonne l'équation de dispersion de Kirchhoff-Langevin, qui décrit la propagation des ondes longitudinales dans les fluides viscothermiques. La nouvelle théorie et procédure d'homogénéisation nonlocale sont validées dans trois cas, portant sur des microgéométries significativement différentes. Dans le cas simple d'un tube circulaire rempli par un fluide viscothermique, on montre que les nombres d'ondes et les impédances prédits par la théorie nonlocale, coïncident avec ceux de la solution exacte de Kirchhoff, connue depuis longtemps. Au contraire, les résultats issus de la théorie locale (celle de Zwikker et Kosten, découlant de la théorie classique d'homogénéisation) ne donnent que le mode le plus attenué, et encore, seulement avec le petit désaccord existant entre la solution simplifiée de Zwikker et Kosten et celle exacte de Kirchhoff. Dans le cas où le milieu poreux est constitué d'un réseau carré de cylindres rigides parallèles, plongés dans le fluide, la propagation étant regardée dans une direction transverse, la vitesse de phase du mode le plus atténué peut être calculée en fonction de la fréquence en suivant les approches locale et nonlocale, résolues au moyen de simulations numériques par la méthode des Eléments Finis. Elle peut être calculée d'autre part par une méthode complètement différente et quasi-exacte, de diffusion multiple prenant en compte les effets viscothermiques. Ce dernier résultat quasi-exact montre un accord remarquable avec celui obtenu par la théorie nonlocale, sans restriction de longueur d'onde. Avec celui de la théorie locale, l'accord ne se produit que tant que la longueur d'onde reste assez grande.
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Metzger, Xavier. "Le terme pardon : emplois et signification." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEH138/document.
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Ce travail doctoral a pour objectif d’analyser la signification du terme pardon dans tous ses emplois en langue française contemporaine. Le cadre théorique de la sémantique argumentative et de la TBS nous a permis de schématiser et de comprendre non seulement les différences de signification dans les emplois du nom commun mais également de discerner le mode d’action de la locution dans toutes ses fonctions argumentatives.Après avoir mis de côté ce qui appartient à la construction encyclopédique de la notion du pardon, à savoir le caractère d’un acte souverain, l’analyse argumentative a permis de décrire toute la richesse de la signification du terme en tant qu’état, processus et achèvement, ainsi que son caractère fondamental de promesse. Elle nous a également amené à dissocier d’un côté l’acte d’excuse performatif dans les échanges réparateurs et, de l’autre, des fonctions argumentatives variées dans les emplois conversationnels et de politesse.Notre démarche a permis d’enrichir les apports du dictionnaire et de l’approche lexicologique. A l’issue de l’analyse d’une centaine d’exemples, nous avons pu rapprocher le terme pardon de celui de paixThis doctoral work aims to analyze the meaning of the term forgiveness in all its uses in contemporary French.The theoretical framework of the argumentative semantics and the TBS allowed us to schematize and understand not only the differences of meaning in the uses of the common noun but also to discern the mode of action of the phrase in all its argumentative functions.After setting aside what belongs to the encyclopedic construction of the notion of forgiveness, namely the character of a sovereign act, the argumentative analysis has allowed to describe all the richness of the meaning of the term as a state, a process and a completion, as well as its fundamental promise. It has also led us to dissociate on the one hand the performative excuse act in repairs and, on the other hand, various argumentative functions in conversational and politeness jobs.Our approach has enriched the contributions of the dictionary and the lexicological approach. At the end of the analysis of a hundred examples, we were able to bring the term forgiveness closer to that of peace
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Falque, Justine. "Classification of P-oligomorphic groups, conjectures of Cameron and Macpherson." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS484/document.
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Les travaux présentés dans cette thèse de doctorat relèvent de la combinatoire algébrique et de la théorie des groupes. Précisément, ils apportent une contribution au domaine de recherche qui étudie le comportement des profils des groupes oligomorphes.La première partie de ce manuscrit introduit la plupart des outils qui nous seront nécessaires, à commencer par des éléments de combinatoire et combinatoire algébrique.Nous présentons les fonctions de comptage à travers quelques exemples classiques, et nous motivons l'addition d'une structure d'algèbre graduée sur les objets énumérés dans le but d'étudier ces fonctions.Nous évoquons aussi les notions d'ordre et de treillis.Dans un second temps, nous donnons un aperçu des définitions et propriétés de base associées aux groupes de permutations, ainsi que quelques résultats de théorie des invariants. Nous terminons cette partie par une description de la méthode d'énumération de Pólya, qui permet de compter des objets sous une action de groupe.La deuxième partie est consacrée à l'introduction du domaine dans lequel s'inscrit cette thèse, celui de l'étude des profils de structures relationnelles, et en particulier des profils orbitaux. Si G est un groupe de permutations infini, son profil est la fonction de comptage qui envoie chaque entier n > 0 sur le nombre d'orbites de n-sous-ensembles, pour l'action induite de G sur les sous-ensembles finis d'éléments.Cameron a conjecturé que le profil de G est équivalent à un polynôme dès lors qu'il est borné par un polynôme. Une autre conjecture, plus forte, a été plus tard émise par Macpherson : elle implique une certaine structure d'algèbre graduée sur les orbites de sous-ensembles, créée par Cameron et baptisée algèbre des orbites, soutenant que si le profil est borné par un polynôme, alors l'algèbre des orbites est de type fini.Comme amorce de notre étude de ce problème, nous développons quelques exemples et faisons nos premiers pas vers une résolution en examinant les systèmes de blocs des groupes de profil borné par un polynôme --- que nous appelons P-oligomorphes ---,ainsi que la notion de sous-produit direct.La troisième partie démontre une classification des groupes P-oligomorphes, notre résultat le plus important et dont la conjecture de Macpherson se révèle un corollaire.Tout d'abord, nous étudions la combinatoire du treillis des systèmes de blocs,qui conduit à l'identification d'un système généralisé particulier, constituébde blocs ayant de bonnes propriétés. Nous abordons ensuite le cas particulier o`u il se limite à un seul bloc de blocs, pour lequel nous établissons une classification. La preuve emprunte à la notion de sous-produit direct pour gérer les synchronisations internes au groupe, et a requis une part d'exploration informatique afin d'être d'abord conjecturée.Dans le cas général, nous nous appuyons sur les résultats précédents et mettons en évidence la structure de G comme produit semi-direct impliquant son sous-groupe normal d'indice fini minimal et un groupe fini. Ceci permet de formaliser une classification complète des groupes P-oligomorphes,et d'en déduire la forme de l'algèbre des orbites : (à peu de choses près) une algèbre d'invariants explicite d'un groupe fini. Les conjectures de Macpherson et de Cameron en découlent, et plus généralement une compréhension exhaustive de ces groupes.L'annexe contient des extraits du code utilisé pour mener la preuve à bien,ainsi qu'un aperçu de celui qui a été produit en s'appuyant sur la nouvelle classification, qui permet de manipuler les groupes P-oligomorphes en usant d'une algorithmique adaptée. Enfin, nous joignons ici notre première preuve, plus faible, des deux conjecturesThis PhD thesis falls under the fields of algebraic combinatorics and group theory. Precisely,it brings a contribution to the domain that studies profiles of oligomorphic permutation groups and their behaviors.The first part of this manuscript introduces most of the tools that will be needed later on, starting with elements of combinatorics and algebraic combinatorics.We define counting functions through classical examples ; with a view of studying them, we argue the relevance of adding a graded algebra structure on the counted objects.We also bring up the notions of order and lattice.Then, we provide an overview of the basic definitions and properties related to permutation groups and to invariant theory. We end this part with a description of the Pólya enumeration method, which allows to count objects under a group action.The second part is dedicated to introducing the domain this thesis comes withinthe scope of. It dwells on profiles of relational structures,and more specifically orbital profiles.If G is an infinite permutation group, its profile is the counting function which maps any n > 0 to the number of orbits of n-subsets, for the inducedaction of G on the finite subsets of elements.Cameron conjectured that the profile of G is asymptotically equivalent to a polynomial whenever it is bounded by apolynomial.Another, stronger conjecture was later made by Macpherson : it involves a certain structure of graded algebra on the orbits of subsetscreated by Cameron, the orbit algebra, and states that if the profile of G is bounded by a polynomial, then its orbit algebra is finitely generated.As a start in our study of this problem, we develop some examples and get our first hints towards a resolution by examining the block systems ofgroups with profile bounded by a polynomial --- that we call P-oligomorphic ---, as well as the notion of subdirect product.The third part is the proof of a classification of P-oligomorphic groups,with Macpherson's conjecture as a corollary.First, we study the combinatorics of the lattice of block systems,which leads to identifying one special, generalized such system, that consists of blocks of blocks with good properties.We then tackle the elementary case when there is only one such block of blocks, for which we establish a classification. The proof borrows to the subdirect product concept to handle synchronizations within the group, and relied on an experimental approach on computer to first conjecture the classification.In the general case, we evidence the structure of a semi-direct product involving the minimal normal subgroup of finite index and some finite group.This allows to formalize a classification of all P-oligomorphic groups, the main result of this thesis, and to deduce the form of the orbit algebra: (little more than) an explicit algebra of invariants of a finite group. This implies the conjectures of Macpherson and Cameron, and a deep understanding of these groups.The appendix provides parts of the code that was used, and a glimpse at that resulting from the classification afterwards,that allows to manipulate P-oligomorphic groups by apropriate algorithmics. Last, we include our earlier (weaker) proof of the conjectures
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Lorenzon, Anna Maria. "Utopia e materialismo: estudo sobre a interpretação blochiana das Onze teses de Marx sobre Feuerbach." Universidade Estadual do Oeste do Parana, 2015. http://tede.unioeste.br:8080/tede/handle/tede/2070.
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Only apparently paradoxical, the concepts of Utopia and Materialism are essential to understand the philosophy of Ernst Bloch, to the extent that underlie what the author calls, in the title of his magnum opus, The Principle of Hope. Reason of controversy between marxist interpreters, Bloch argues that many of the foundations of his Concrete Utopia part of the own philosophy of Karl Marx, and, based on this claim, we will try to explain in this work, the blochian arguments that prove not only the conciliation of utopia and materialism, but also the intrinsic relationship of the marxism with the blochian notion of concrete utopia. The so-called Marx's Eleven Theses on Feuerbach, were, according to Bloch, the first writings to indicate the reality which can be changed, out of the materialism of the base behind the lines into that of the Front and therefore received a major chapter in The Principle of Hope Changing the World or Marx's Eleven Theses on Feuerbach which is our object of study, as well as others texts of the young Marx indicated by Bloch. Our author brings contributions to marxist studies in that it suggests the rehabilitation of the revolutionary imagination within marxism, doing it without contesting the need for economic and political analysis, but integrating utopian thinking, in all its dimensions, on the horizon of the marxist transformation project of the world. The point of convergence of blochian philosophy with Marxian theory is perceived in the common horizon of the authors: the humanization of the world and the release from alienation and exploitation of human beings. Our work is structured according to the grouping of the Theses used by Bloch, according to a philosophical criteria, sorting them by themes and content. In the first chapter, we discuss the materialistic-utopian elements of blochian philosophy having as guide the interpretation made by the author of the epistemological and anthropological-historical groups of the marxian Eleven Theses respectively, theses 5, 1 and 3, and theses 4, 6, 7, 9 and 10. Already present in the classic questions of German idealism, reappear here problems related to the reconciliation of nature and spirit, especially the blochian concept of possibility , which appears as a mediator category of classical concepts freedom and necessity . Meanwhile, in the anthropological sphere, highlights the question of the human, surfacing recovery of humanism found in the author's thought. The humanization process is only possible, in the blochian perspective, with theory and philosophical praxis connected, both in marxist molds. As a result, in the second chapter we will cover the blochian modes and criteria for the transformation of the world. In this sense, the thesis 2 e 8, theory-praxis group, not only deal with the activity of thought, but also concerned about the criteria that demonstrate and validate the truth of a theory that is intended to serve as a guide to transforming actions, and culminate in the famous thesis 11, which guides the author's conception of philosophy, that is, a philosophy understood in the future-laden properties of reality .
Apenas aparentemente paradoxais, os conceitos de Utopia e Materialismo são imprescindíveis para compreender a filosofia de Ernst Bloch, na medida em que fundamentam aquilo que o autor denomina, no título de sua obra magna, O Princípio Esperança. Motivo de controvérsias entre os intérpretes marxistas, Bloch alega que muitos dos fundamentos de sua Utopia Concreta fazem parte da própria filosofia de Karl Marx, e, baseando-nos nessa alegação, tentaremos explicitar, neste trabalho, os argumentos blochianos que comprovam não só a conciliação de utopia e materialismo, mas também a relação intrínseca do marxismo com a noção blochiana de utopia concretamente concebida. As chamadas Onze teses de Marx sobre Feuerbach, foram, segundo Bloch, os primeiros escritos a indicar o caminho para a realidade passível de transformação, do materialismo da etapa para o da linha de frente e, por isso, receberam um capítulo destaque em O Princípio Esperança A transformação do mundo ou As Onze teses de Marx sobre Feuerbach , que é nosso objeto de estudo, assim como outros textos do jovem Marx indicados por Bloch. Nosso autor traz contribuições para os estudos marxistas na medida em que sugere a reabilitação da imaginação revolucionária no interior do marxismo, fazendo-o sem contestar a necessidade da análise econômico-política, mas integrando o pensamento utópico, em todas as suas dimensões, no horizonte do projeto marxista da transformação do mundo. O ponto de convergência da filosofia blochiana com a teoria marxiana é percebido no horizonte comum dos autores: a humanização do mundo e a libertação da alienação e da exploração do ser humano. Nosso trabalho está estruturado de acordo com o agrupamento das Teses utilizado por Bloch, segundo um critério filosófico, separando-as por temas e conteúdos. No primeiro capítulo, abordaremos os elementos utópico-materialistas da filosofia blochiana tendo como guia a interpretação feita pelo autor dos grupos epistemológico e histórico-antropológico das Onze Teses marxianas respectivamente, teses 5, 1 e 3, e teses 4, 6, 7, 9 e 10. Já presentes nas questões clássicas do idealismo alemão, reaparecem aqui os problemas relacionados à conciliação da natureza e do espírito, com destaque para o conceito blochiano de possibilidade , que aparece como categoria mediadora dos conceitos clássicos de liberdade e de necessidade . Enquanto isso, na esfera antropológica, evidencia-se a pergunta pelo humano, vindo à tona a valorização do humanismo encontrado no pensamento do autor. O processo de humanização só é possível, na perspectiva blochiana, com teoria e práxis filosóficas conjugadas, ambas nos moldes marxistas. Em vista disso, no segundo capítulo abordaremos os modos e critérios blochianos para a transformação do mundo. Nesse sentido, as teses 2 e 8, do grupo teoria-práxis, não apenas tratam da atividade do pensamento, como também preocupam-se com os critérios que comprovam e validam a veracidade de uma teoria que pretende servir como guia para ações transformadoras, e culminam na famosa tese 11, que orienta a concepção de filosofia do autor, isto é, uma filosofia entendida nas propriedades da realidade portadoras do futuro .
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Adouane, Amine Mohamed. "Dynamic management of spectral resources in LTE networks." Thesis, Versailles-St Quentin en Yvelines, 2015. http://www.theses.fr/2015VERS007V/document.
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La croissance exponentielle du nombre de dispositifs communicants et des services sans fils émergents fixe des objectifs toujours plus haut pour répondre à la demande de capacité sans cesse croissante des utilisateurs. Cela pose des défis constants pour atteindre les objectifs envisagés. La réutilisation spectrale élevée (High efficiency spectral reuse) a été adopté, cependant, elle conduit à des interférences accrues sur le réseau, ce qui dégrade les performances. L'OFDM (Orthogonal Frequency Division Multiplexing) est utilisé comme solution dans les réseaux de 4 G. Grâce à son orthogonalité, l'OFDM élimine l'interférence intra-cellulaire, mais l'interférence inter-cellule reste importante. Plusieurs méthodes connues sous le nom d'Inter-Cell interférences coordination (ICIC) ont été proposées pour les diminuer. L'ICIC permet la gestion des ressources radio coordonnée entre plusieurs cellules appelées ENodeB. Ces eNodeB peuvent partager les informations nécessaires grâce à l'interface X2 qui les relient, ces informations sont transmises par des messages LTE normalisés. Lorsque les ENodeBs sélectionnent égoïstement les ressources, la théorie de jeux non-coopératifs est largement appliquée pour trouver un juste équilibre. Dans cette thèse, nous mettons l'accent sur l'ICIC pour la liaison descendante d'un système OFDMA cellulaire dans le contexte du projet SOAPS (Spectrum opportuniste accès à la Sécurité publique). Ce projet a pour but l'amélioration de la planification des ressources de fréquences pour fournir des services à large bande dans les systèmes PMR (radiocommunications mobiles privées) en utilisant les technologies LTE. Nous adressons le problème d'ICIC en proposant quatre solutions différentes sous forme d'algorithmes entièrement décentralisés, ces algorithmes se basent sur la théorie des jeux non-coopératifs avec des équilibres de Nash purs des jeux considérésThe exponential growth in the number of communications devices has set out new ambitious targets to meet the ever-increasing demand for user capacity in emerging wireless systems. However, the inherent impairments of communication channels in cellular systems pose constant challenges to meet the envisioned targets. High spectral reuse efficiency was adopted as a solution to higher data rates. Despite its benefits, high spectral reuse leads to increased interference over the network, which degrades performances of mobile users with bad channel quality. To face this added interfence, OFDM (Orthogonal Frequency Division Multiplexing) is used for the new 4th generation network. Thanks to its orthogonality OFDM eliminates the intra-cellular interference, but when the same resources are used in two adjacents cells, the inter-cell interference becomes severe. To get rid of the latter, several methods for Inter-Cell Interference Coordination (ICIC) have been proposed. ICIC allows coordinated radio resources management between multiple cells. The eNodeBs can share resource usage information and interference levels over the X2 interface through LTE-normalized messages. Non-cooperative game theory was largely applied were eNodeBs selfishly selects resource blocks (RBs) in order to minimize interference. In this thesis, we stress on ICIC for the downlink of a cellular OFDMA system in the context of the SOAPS (Spectrum Opportunistic Access in Public Safety) project. This project focuses on the improvement of frequency resource scheduling for Broadband Services provision by PMR (Private Mobile Radio) systems using LTE technologies. We addressed this problem with four different solutions based on Non-cooperative game theory, three algorithms are devoted to RB selection in order to manage the interference, while the last one is a power control scheme with power economy and enhanced system performances
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Farvacque, Manon. "Evaluation quantitative du risque rocheux : de la formalisation à l'application sur les linéaires et les zones urbanisées ). How argest wildfire events in France? A Bayesian assessment based on extreme value theory ). Hows rockfall risk impacted by land-use and land-cover changes? Insights from the French Alps. Quantitative risk assessment in a rockfall-prone area: the case study of the Crolles municipality (Massif de la Chartreuse, French Alps)." Thesis, Université Grenoble Alpes, 2020. https://tel.archives-ouvertes.fr/tel-02860296.
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L’aléa chute de blocs est caractérisé par le détachement brutal d’une masse rocheuse, depuis une paroi (sub)verticale, qui se propage rapidement vers l’aval par rebonds successifs. Ces événements, fréquents en zones de montagne, représentent un aléa majeur pour les infrastructures collectives et les habitations, et induisent fréquemment de graves accidents. En France, par exemple, le détachement d’un volume rocheux de 30 m3 en 2014 a provoqué le déraillement du train touristique des Pignes, faisant deux victimes et neuf blessés. En 2015, l’endommagement des voies et la perturbation du trafic ferroviaire suite à un événement rocheux survenu entre Moûtiers et Bourg-Saint-Maurice a induit 1.34M€ de réparations, et 5.4M€ de dommages indirects.Ces différents événements illustrent bien notre vulnérabilité face aux événements rocheux, et soulignent que les collectivités locales et les pouvoirs publics sont encore fréquemment démunis en matière de méthode de diagnostic et d’analyse du risque de chute de blocs. Dans ce contexte, l’évaluation des risques par une approche de type quantitative, appelée QRA (Quantitative Risk Assessment), est devenue incontournable pour l’aménagement des territoires de montagne et le choix des mesures de mitigation. Chaque terme de l’équation du risque, dont les composantes principales sont l’aléa, la vulnérabilité, et l’exposition, sont alors fidèlement quantifiés, offrant des informations sur les dommages potentiels.Malgré le vif intérêt alloué aux approches de type QRA pour la gestion des risques rocheux, de telles applications restent encore inhabituelles. La rareté de ces approches est principalement liée à la difficulté à évaluer précisément chacune des composantes du risque. De plus, les quelques études qui proposent une approche QRA dans le domaine rocheux font généralement l’hypothèse de la stationnarité du processus, alors que l’étalement urbain, ou l’évolution de l’occupation des sols, qui modifient le fonctionnement du processus ne sont pas intégrés. Enfin, le risque rocheux – comme la plupart des autres risques naturels – est exprimé par la moyenne des dommages. Cependant, cette moyenne arithmétique est associée à plusieurs faiblesses, et n’offre qu’une seule valeur du risque, généralement inadaptée aux différentes contraintes auxquelles doivent faire face les gestionnaires. Dans ce contexte, l’objectif de cette thèse est de renforcer les bases formelles du calcul du risque dans le domaine des chutes de blocs, d’évaluer les effets des changements environnementaux sur le risque rocheux, et de proposer une méthode où le risque de chutes de blocs est quantifié à partir de mesures de risque alternatives à la moyenne arithmétique. A cet effet, nous proposons une procédure holistique de QRA où le risque rocheux est quantifié en combinant un modèle de simulation trajectographique avec des courbes de vulnérabilité et un large spectre de volume rocheux et de zones de départ de chutes de blocs. La faisabilité et l’intérêt de cette procédure est illustré sur deux cas d’études réels : la commune de Crolles (Alpes Françaises), et la vallée de l’Uspallata (Cordillère des Andes). Par ailleurs, nous mesurons l’effet des changements environnementaux sur le risque de chutes de blocs en appliquant la QRA dans différents contextes d’utilisation et d’occupation des sols. Enfin, nous proposons une approche innovante où deux mesures de risque, dites "quantile-based measures", sont introduites. Ces dernières permettent une meilleure prise en compte des événements extrêmes et permettent d’envisager la gestion du risque à divers horizons temporelsRockfalls are a common type of fast moving landslide, corresponding to the detachment of individual rocks and boulders of different sizes from a vertical or sub-vertical cliff, and to their travel down the slope by free falling, bouncing and/or rolling. Every year, in the Alpine environment, rockfalls reach urbanized areas causing damage to structures and injuring people. Precise rockfall risk analysis has therefore become an essential tool for authorities and stakeholders in land-use planning.To this aim, quantitative risk assessment (QRA) procedures originally developed for landslides have been adapted to rockfall processes. In QRAs, rockfall risk for exposed elements is estimated by coupling the hazard, exposure and vulnerability components. However in practice, the estimation of the different components of risk is challenging, and methods for quantifying risk in rockfall-prone regions remain scarce. Similarly, the few studies which so far performed QRAs for rockfall assume stationary, precluding reliable anticipation of the risk in a context where environmental and societal conditions are evolving rapidly and substantially. Moreover, rockfall risk remains - as for most of natural hazards - always defined as the loss expectation. This metric offers a unique risk value, usually inconsistent with short/long term constraints or trade-offs faced by decision-makers.On this basis, this PhD thesis therefore aims at (i) reinforcing the basis of QRA, (ii) assessing the effect of environmental changes on rockfall risk, and (iii) proposing method for quantifying rockfall risk from measures of risk alternative to the standard loss expectation. In that respect, we propose a QRA procedure where the rockfall risk is quantified by combining a rockfall simulation model with the physical vulnerability of potentially affected structures and a wide spectrum of rockfall volumes as well as release areas. The practicability and interest of this procedure is illustrated on two real case studies, i.e. the municipality of Crolles, in the French Alps, and the Uspallata valley, in the central Andes mountains. Similarly, the effect of environmental changes on rockfall risk is considered by comparing rockfall risk values in different land-use and land-cover contexts. Last, we implement in our procedure on an individual basis two quantile-based measures, namely the value-at-risk and the expected-shortfall, so as to assess rockfall risk for different risk-management horizon periods. All in all, this PhD thesis clearly demonstrates the added value of QRA procedure in the field of rockfall, and reinforces its basis by implementing analytical, statistical or numerical models. The resulting panel of risk maps, also proposed under non-stationary contexts, are of major interest for stakeholders in charge of risk management, and constitute appropriate basis for land-use planning and prioritizing of mitigation strategies
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Samb, El Hadji. "Contrôlabilité de systèmes paraboliques couplés : quelques phénomènes hyperboliques dans le contrôle des équations paraboliques." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0223.
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Nous étudions la contrôlabilité à zéro de systèmes paraboliques linéaires, en particulier les phénomènes qualifiés "d'hyperboliques" dans le contrôle des systèmes paraboliques, tels que des conditions sur la géométrie de la zone de contrôle ou sur le temps. Nous nous sommes intéressés, dans un premier temps, à une extension à la dimension N>1 d'espace d’un résultat dans Dolecki 1973, publié en 1973, qui donne une caractérisation de la contrôlabilité ponctuelle de l'équation de la chaleur mono-dimensionnelle. Nous prouvons la contrôlabilité interne de l’équation de la chaleur N-dimensionnelle sur des domaines de la forme (0,1) x Ω2, avec Ω2 un domaine borné et régulier de RN -1, N>1, lorsque le contrôle est exercé sur {x0} x ω2, avec x0 ∈ (0,1) et ω2 ⊆ Ω2. Notre résultat s’appuie sur la stratégie dite de Lebeau-Robbiano et exige une limite supérieure du coût du contrôle mono-dimensionnel sur (0,1). Dans une seconde partie nous avons étudié la contrôlabilité à zéro de deux équations paraboliques couplées par une matrice dont les coefficients dépendent de l’espace. Dans ce cas un phénomène étonnant apparaît : la condensation des fonctions propres. Les travaux précédents imposaient que la famille des fonctions propres de l’opérateur parabolique considéré forme une base de Riesz. Le système que nous avons étudié ne satisfait pas cette hypothèse. S’inspirant de la "méthode des moments par blocks", proposée par Benabdallah,Boyer et Morencey 2018, nous formulons l’expression d’un temps minimal de contrôle T0 dépendant de la condensation simultanée de fonctions propres et valeurs propresThis thesis focuses on the zero controllability of linear parabolic systems, in particular on new phenomena called "hyperbolic" in the control of parabolic systems, such as conditions on the geometry of the control zone or on time. We start with the study of an extension, to the N>1 space dimension, of a result in Dolecki 1973 published in 1973. Which gives a characterization of the pointwise controllability at time T of the one-dimensional heat equation. We obtain a necessary and sufficient condition that completely characterizes the distributed null-controllability of the N-dimensional heat-equation, on domains of the form (0,1) x Ω2, with Ω2 a smooth domain of RN-1, N>1, when the control is exerted on {x0} x ω2, with x0 ∈ (0.1) and ω2 ⊆ Ω2. Our result is based on the Lebeau-Robbiano strategy and requires an upper bound of the cost of the one dimensional pointwise null-control on (0.1). In a second part we studied the null-controllability of two parabolic equations coupled by a matrix whose coefficients depend on space. In this case a surprising phenomenon appears : the condensation of eigenfunctions.The previous work required that the family of eigenfunctions to the parabolic operator considered form a Riesz base. The system we studied does not satisfy this hypothesis. Inspired by the "block moment method", proposed in Benabdallah,Boyer et Morencey 2018, we formulate an expression of a minimum time of control T0 depending on the simultaneous condensation of eigen values and eigen functions
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Lévêque, Gaëtan. "Manipulation d'atomes froids par champs optiques confinés : théorie et simulation numérique." Phd thesis, Université Paul Sabatier - Toulouse III, 2003. http://tel.archives-ouvertes.fr/tel-00006141.
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Ce travail porte sur l'interaction dipolaire d'atomes neutres avec un rayonnement électromagnétique structuré sur une échelle plus petite que la longueur d'onde de la lumière. Ces champs optiques sont obtenus par interaction d'une onde évanescente de Fresnel avec des nanostructures diélectriques à haut indice de réfraction déposées à la surface d'un prisme. Deux thèmes sont abordés. Le premier concerne l'étude, d'un point de vue théorique, d'une expérience de diffraction d'atomes neutres par un miroir atomique nanostructuré. La modulation du potentiel provient de l'interaction de l'onde évanescente avec un réseau matériel périodique sub-longueur d'onde. Dans un premier temps, les spécificités de cette méthode de diffraction sont dégagées par un calcul analytique reposant sur plusieurs approximations concernant la structure du champ optique et la structure interne atomique. Elle est ensuite complétée d'une étude numérique qui permet de prendre en compte toute la complexité du problème. Le deuxième thème est une étude du comportement en champ proche de cavités résonantes constituées d'ensembles d'anneaux diélectriques couplés. Ces nanostructures, adressées par un faisceau gaussien évanescent, amplifient à la résonance l'intensité et le gradient du champ électrique d'un facteur de plusieurs centaines. L'objectif est de trouver une configuration permettant la concentration ou la focalisation transversale d'un faisceau d'atomes en vue d'applications en nanolithographie. Cette étude est effectuée en couplant une méthode ab-initio permettant un calcul précis du champ rayonné dans tout l'espace à un modèle analytique simplifié décrivant le comportement modal de ces structures en fonction de leurs caractéristiques géométriques.
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Amoussou-Guenou, Yackolley. "Gouvernance des biens communs dans les blockchains." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS043.
Full textAbstract:
Les blockchains (ou chaîne de blocs) font partie des technologies les plus attrayantes, autant dans le domaine scientifique que pour le grand public. Une blockchain est un registre distribué dont l’objectif est de garantir de la transparence, de l’intégrité des données et d’autres avantages par rapport aux registres centralisés. La technologie blockchain a été révélée et est devenue populaire grâce à l’avènement de la cybermonnaie Bitcoin. Depuis 2008 et la création de Bitcoin, les blockchains sont devenue extrêmement populaires, avec un intérêt à son pic en 2017. Les blockchains sont quasiment une technologie “à la mode”: il existe un observatoire de la blockchain initié par la Commission Européenne, des événements blockchains dans plusieurs pays, etc. La plupart des blockchains ont comme application la finance, mais les propriétés qu’elles promettent sont intéressantes et utiles pour bien des domaines (ex : médecine, notariat, etc.). Malgré les promesses et intérêts, afin d’espérer une meilleure adoption, il est nécessaire de s'assurer que la technologie est viable du point de vue environnemental, que les garanties promises sont satisfaites, qu'elle puisse être utilisée dans les environnements réels, etc. Dans cette thèse, nous définissons le problème résolu par les blockchains à comité ainsi que leur équité ; cela a permis de corriger une des blockchains les plus utilisées. Notre second apport majeur est une méthodologie permettant d’étudier le comportement des participants dans les blockchains. Grâce à cela, nous montrons les conditions nécessaires où le comportement rationnel des participants mène à des situations où les propriétés des blockchains sont satisfaitesBlockchains are one of the most appealing technologies over the last years, both for scientists and for the general public. Blockchains are distributed ledgers that aim to offer transparency, integrity and many more advantages over their centralised counterparts. Blockchains were “revealed” and became popular thanks to the creation and rise of the cryptocurrency Bitcoin. Over the years, blockchain technologies become more and more popular with an exceptional peak in 2017. Blockchains are becoming mainstream technologies, as there is an observatory for blockchains established by the European Commission, blockchain forums in many countries, blockchain start-ups are flourishing, scientific conferences are discussing the topic, and even some scientific conferences are now specifically dedicated to the technology, etc. The blockchain technology promises, thanks to its integrity and transparency properties to be useful and interesting in various domains, and not only for financial systems. However, many questions and doubts float around it. Is it environmentally viable? Is the technology even ensuring its promises? Can they be used in real-life settings, etc. In this thesis, using the lens of distributed systems, we study and define the properties of committee-based blockchains and their fairness; that definition allows formalising and helping correct one of the most used blockchain of that class. Furthermore, adding lenses from game theory, we propose a methodology to analyse the rational behaviours of participants in a blockchains system. Using that methodology, we show, under different mechanisms of rewards, the necessary conditions needed to ensure the blockchain properties