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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Explicit class field theory for rational function fields /

Rakotoniaina, Tahina. January 2008 (has links)
Thesis (MSc)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.
22

Topics in lattice field theory /

Endres, Michael G., January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (p. 72-77).
23

Determinação da razão de ramificação e dos fatores de forma do decaimento semi-leptônico \"K IND.L\"-> \"\"pi\" POT.0\" \"\"pi\" POT.+/-\" e \"ANTPOT.-/+ \"nü\"\". / Determination of the branching ratio and form factors of semi-leptonic decay \"K IND.L\"-> \"\"pi\" POT.0\" \"\"pi\" POT.+/-\" e \"ANTPOT.-/+ \"nü\"\".

Edivaldo Moura Santos 24 August 2005 (has links)
Mediu-se a razão de ramificação do decaimento semi-leptônico \"K IND.L->\"pi\"POT.0\"\"pi\" POT, +/-\" e \"ANTPOT.-/+nu\" (\"BR IND.\"K POT.0\"IND.E4\" = [5.19 =/- \"0.09 IND.sist\"] X \"10 POT.-5\"), baseado numa amostra de 4000 eventos sobre um fundo residual a ser subtraído de 143 (3.6%) eventos. Os dados foram coletados pelo experimento KTeV no Fermilab. A contaminação residual é compatível com \"K IND.->\"\"pi\"POT.=/-\" e \" ANTPOT.=/-\"nu\"\"gama\" ou \"K IND.L->\"\"pi\"POT.=/-\" e \" ANTPOT.=/-\"nu\" ou \"K IND.L\" ->\"pi\" POT.=/-\" e \" ANTPOT.=/-\"nu\" na presença de um ou dois fótons acidentais, respectivamente. A contribuição dominante ao erro sistemático advém de uma discrepância observada entre dados/Monte Carlo com respeito à eficiência de detecção ao longo da direção do feixe de káons. O modo de normalização utilizado na medida da razão de ramificação foi \"K IND.L\" ->\"pi\"POT.=/-\" e \" ANTPOT.=/-\"nu\". Correções radiativas eletromagnéticas de ordem \"\"alfa\"IND.QED\" foram incluídas no Monte Carlo de simulação, tendo a fração radiativa sido conferida por meio de um cálculo analítico, incluindo bremsstrahlung interno e correções virtuais, das quais a correção de vértice fornece uma contribuição finita após o processo de renormalização. Por meio de um ajuste ao espectro e construído do decaimento, três dos fatores de forma que parametrizam o elemento de matriz hadrônica também foram medidos, cujos valores indicam uma violação da regra empírica \"delta\"I=1/2 de cerca de 2%. A dependência, em primeira ordem, de um dos fatores de forma com o momento transferido aos léptons \"q POT.2\" também foi obtida, possibilitando a resolução da ambiguidade quadrática entre \"\"gama\"IND.K\" IND.E.4\" a constante de acoplamento \"L IND.3\" em Teoria de Perturbação Quiral e permitindo uma medida direta dessa constante (\"L IND.3\"=[-4.0 =/- 0.3] X \"10 POT.-3\"). / We have measured the branching fraction of the \"K IND.L->\"pi\"POT.0\"\"pi\" POT, +/-\" e \"ANTPOT.-/+nu\" decay (\"BR IND.\"K POT.0\"IND.E4\" = [5.19 =/- \"0.09 IND.sist\"] X \"10 POT.-5\"), based on a 4000 candidates sample over a residual background of 143 (3.6%) events. The data was collected by the KTeV experiment at Fermilab. The remaining contamination is consistent with \"K IND.->\"\"pi\"POT.=/-\" e \" ANTPOT.=/-\"nu\"\"gama\" ou \"K IND.L->\"\"pi\"POT.=/-\" e \" ANTPOT.=/-\"nu\" ou \"K IND.L\" ->\"pi\" POT.=/-\" e \" ANTPOT.=/-\"nu\" plus one or two accidental photons, respectively. The leading contribution to the systematic error comes from an observed discrepancy between data/Monte Carlo for the detection efficiency along the kaon beam direction. The \"K IND.L\" ->\"pi\"POT.=/-\" e \" ANTPOT.=/-\"nu\" decay was used as normalization mode for the purpose of branching fraction measurement. Radiative corrections of order \"\"alfa\"IND.QED\" were included into the Monte Carlo, the radiative fraction being crosschecked through an analytical calculation, which included internal bremsstrahlung and virtual corrections, of which the vertex correction gives a finite contribution after renormalization. Through a fit to the reconstructed decay spectrum, three form factors appearing in the parametrization of the hadronic matrix element were measured, whose values allow for a violation of the empirical \"delta\"I=1/2 rule of about 2%. We have also measured the first order dependence on the transfered momentum to the leptons of one of the form factors, solving the quadratic ambiguity between \"\"gama\"IND.K\" IND.E.4\" and the low energy coupling constant \"L IND.3\" from Chiral Perturbation Theory, allowing for a direct measurement of this constant (\"L IND.3\"=[-4.0 =/- 0.3] X \"10 POT.-3\").
24

Atores empresariais e sustentabilidade: no jogo político entre econômico, social e ambiental / Business actors and sustainability: in the political game between economic, social and environmental

Moraes, Marcela Oliveira Scotti de 11 June 2019 (has links)
O objetivo deste estudo é analisar o envolvimento de atores empresariais com a agenda da sustentabilidade no Brasil. O foco da pesquisa foi sobre a trajetória de um grupo de atores empresariais na criação de cinco organizações: Instituto Ethos de Empresas e Responsabilidade Social (ETHOS); Instituto Akatu pelo Consumo Consciente (AKATU); Instituto São Paulo Sustentável (ISPS); Instituto Democracia e Sustentabilidade (IDS); e Rede de Ação Política pela Sustentabilidade (RAPS). A pesquisa descreve como estes atores empresariais iniciaram sua atuação coletiva e política em torno de uma agenda econômica e da ideia de um pacto social, passando, por meio das organizações analisadas a incorporar a agenda da sustentabilidade como estratégia de ação. O estudo aponta como diferentes contornos dados à agenda da sustentabilidade nas organizações analisadas permitiram induzir a cooperação de atores sociais ligados a setores distintos, incluindo empresas, ONGs e lideranças políticas / The objective of this study is to analyze the involvement of business actors in the sustainability agenda in Brazil. The focus of the research was on the trajectory of a group of business actors in the creation of five organizations: Instituto Ethos de Empresas e Responsabilidade Social (ETHOS); Instituto Akatu pelo Consumo Consciente (AKATU); Instituto São Paulo Sustentável (ISPS); Instituto Democracia e Sustentabilidade (IDS); and Rede de Ação Política pela Sustentabilidade (RAPS). The research describes how these corporate actors began their collective and political actions around an economic agenda as well as the idea of a social pact, incorporating the sustainability agenda as an action strategy. The study points out how different outlines given to the sustainability agenda in the analyzed organizations helped to induce the cooperation of social actors linked to different sectors, including companies, NGOs and political leaders
25

Scaling conditional random fields for natural language processing /

Cohn, Trevor A. January 2007 (has links)
Thesis (Ph.D.)--University of Melbourne, Dept. of Computer Science and Software Engineering, Faculty of Engineering, 2007. / Typescript. Includes bibliographical references (leaves 171-179).
26

Uniform companions for expansions of large differential fields

Solanki, Nikesh January 2014 (has links)
No description available.
27

Dynamiques réglementaires et planification des firmes : les leçons des limites européennes d’émissions de polluants dans l’automobile / Regulatory dynamics and firms' planning : the lessons of the European air pollutants regulations in the automotive sector

Klebaner, Samuel 06 December 2018 (has links)
L’objectif de cette thèse est de comprendre les mécanismes permettant à une firme industrielle d’agir et de réagir à la règlementation. Le retour de la politique industrielle dans les pays développés s’accompagne d’un regain d’intérêt pour l’étude des effets des politiques industrielles dont la règlementation dans le comportement des firmes régulées. Cependant, les travaux portant sur la « capture règlementaire » ne peuvent pas prendre en compte simultanément la complexité du processus de production de la règle et les mécanismes concrets d’intégration de cette règle dans les activités économiques des firmes. Pour ouvrir ces deux boites noires, nous construisons dans un premier temps un cadre analytique fondé sur la théorie des champs. Ce cadre considère la règlementation comme une institution, et permet d’analyser à la fois la dynamique règlementaire et la dynamique industrielle qu’elle affecte. Dans un second temps, nous élucidons cette double dynamique en étudiant empiriquement les trajectoires des constructeurs en Europe face aux limites d’émissions de polluants atmosphériques. En explicitant tout d’abord les logiques technico-économiques que cette règlementation implique, nous élucidons ensuite la genèse et la dynamique de cette règlementation, afin de mettre en évidence le rôle de la structure et des acteurs dans la production et transformation règlementaire. Enfin, nous montrons comment cette règle est incorporée au sein du processus de planification des activités des constructeurs automobiles. Pour conclure, nous montrons que les enchevêtrements et décalages entre la dynamique règlementaire et de planification impliquent des comportements économiques non déductibles ex ante, du fait de l’incertitude permanente produite par ces dynamiques. / The aim of this thesis is to understand the organizational and institutional mechanisms that drive a manufacturing firm to act on, and react to regulations. The comeback of the industrial policy in developed countries heightens the interest of studies on the effect of such policy, and particularly of regulations on regulated firms. However, scholars in the field of “regulatory capture” cannot consider both the complexity of the rules production and the concrete mechanisms of rules interpretation and integration in the firms’ economic activities. To open these two “black boxes”, we construct first a methodological framework based on the theory of fields. This framework considers regulations as an institution, and permits the analysis of both regulatory dynamics and affected industrial dynamics. Second, we elucidate this double dynamics by empirically studying the car manufacturers’ trajectories in Europe in relation to the air pollutants emissions limits. In clarifying the technical-economic context surrounding this regulation, we then elucidate its genesis and dynamics, highlighting the role of institutions and actors in the rule-making and transformation processes. Then, we show how air pollutants emissions limits are incorporated into the planning process of the car manufacturers’ activities. To conclude, we show that the interactions and inadequacies between the regulations dynamics and the planning activities imply nondeductible ex ante behaviors, as these two dynamics produce permanent uncertainty.
28

Reconfiguração do mercado brasileiro de música : os incumbentes e os novos capitais

Toyama, Míriam Costa 28 August 2015 (has links)
Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-09-23T12:54:21Z No. of bitstreams: 1 TeseMCT.pdf: 3476416 bytes, checksum: 6845703b450e9fbf4fc6b94ebbf91fbe (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T18:00:39Z (GMT) No. of bitstreams: 1 TeseMCT.pdf: 3476416 bytes, checksum: 6845703b450e9fbf4fc6b94ebbf91fbe (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T18:00:45Z (GMT) No. of bitstreams: 1 TeseMCT.pdf: 3476416 bytes, checksum: 6845703b450e9fbf4fc6b94ebbf91fbe (MD5) / Made available in DSpace on 2016-10-04T18:00:52Z (GMT). No. of bitstreams: 1 TeseMCT.pdf: 3476416 bytes, checksum: 6845703b450e9fbf4fc6b94ebbf91fbe (MD5) Previous issue date: 2015-08-28 / Não recebi financiamento / This doctoral dissertation seeks to explain the changes in the music market in the last decade using the Field Theory, by Fligstein and McAdam (2012). Thus, we consider the music market a strategic field of action, which, according to the authors is in frequent adjustment and are subject to external shocks. In this way, through events in nearby fields, the development of innovations that allowed the unauthorized sharing and downloading content over the internet has had a profound impact on the music market, and later on other cultural goods markets. Initial reactions of the incumbent actors have been through strategies that had already been used in earlier times: law suits, educational campaigns and pressuring the government in favor of a stronger legislation. Thus, the reactions of incumbent actors were acoording to what explains the theory, the use of strategies known to restore the status quo. However, due to the crisis that shook the ability of incumbent actors to reproduce their advantages, new players entered the market. In addition, incumbent actors gave way and changed their business models, establishing relations with the new entrants, and adopting new business models leveraging the internet as a means of distribution, dissemination and others. Record companies also started expande their activtities, working with artist's career management. Thus, according to the analysis of the work, we concluded that there was a change in the business model, and that in the Brazilian case these changes followed the international trends. Through research field we conclude that Brazilian companies have adopted the distribution of digital music through online stores and through cell phone companies, streaming services as well as the actors have adopted the 360 contracts. / No presente trabalho busca-se explicar as modificações ocorridas no mercado de música de massa na última década utilizando como referencial teórico a Teoria dos Campos de Fligstein e McAdam (2012). Considera-se o mercado de música um campo de ação estratégica que, de acordo com os autores, está em frequente ajuste e sujeito a choques externos. Transformações em campos próximos, como o desenvolvimento de inovações que permitiram o compartilhamento e download não autorizado de conteúdo através da internet, tiveram impacto profundo sobre o mercado de música e, posteriormente, sobre outros mercados de bens culturais. As reações iniciais dos atores incumbentes constituíram estratégias que já haviam utilizado em momentos anteriores: processos, campanhas educativas e pressões sobre o governo. Tais reações são explicadas pela teoria dos campos: a utilização de estratégias conhecidas a fim de restabelecer o status quo. Entretanto, as mudanças abalaram a capacidade dos atores incumbentes de reprodução de suas vantagens quando entraram novos atores no mercado. Além disso, os atores incumbentes cederam e modificaram seus modelos de negócios, estabelecendo relações com os novos entrantes e adotando modelos de negócios que utilizavam a internet como meio de distribuição, divulgação entre outros. As gravadoras também passaram a atuar de forma mais abrangente, trabalhando com a administração da carreira do artista. Desta forma, de acordo com a análise feita neste trabalho, conclui-se que houve mudanças no modelo de negócios e que, no caso brasileiro, essas mudanças seguiram as tendências internacionais. A pesquisa de campo realizada possibilitou mostrar que as empresas brasileiras adotaram a distribuição de música digital através de venda online, através de empresas de telefonia celular e serviços de streaming, assim como parte dos atores adotaram os contratos 360°. O presente trabalho utiliza pesquisa bibliográfica e estudo de caso para analisar o objeto de estudo.
29

Campos escalares aplicados em cosmologia / Scalar fields applied in cosmology

Vieira, Lucas Elias 13 July 2018 (has links)
Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-08-21T12:44:31Z No. of bitstreams: 2 Dissertação - Lucas Elias Vieira - 2018.pdf: 1438523 bytes, checksum: 81df75730e0ab41f69b4619af81cd7a2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-08-22T12:42:43Z (GMT) No. of bitstreams: 2 Dissertação - Lucas Elias Vieira - 2018.pdf: 1438523 bytes, checksum: 81df75730e0ab41f69b4619af81cd7a2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-08-22T12:42:43Z (GMT). No. of bitstreams: 2 Dissertação - Lucas Elias Vieira - 2018.pdf: 1438523 bytes, checksum: 81df75730e0ab41f69b4619af81cd7a2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-07-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, we study topological defects in classical field theory aiming applications in cosmology. Topological and non-topological solutions were investigated in two dimensions, where we also analyzed the stability of some of these. We consider models of one and two real scalar fields, whose solutions were obtained via quadrature, BPS and orbit methods. The stability of these solutions also were investigated in some cases. In order to apply scalar field theory in cosmology, we revisit some topics of general relativity, such that the principle of equivalence, Einstein's field equations and Schwarzschild's solution for Einstein's equation. We also present some topics in cosmology, relevant to the present work, such that the cosmological principle, Hubble's law and cosmological inflation. We discuss the solutions of the Einstein's equations in the FRW metric in the so-called Hot Big Bang model-the universe composed of matter and radiation. In order to solve some problems of initial conditions of the universe, we introduce the inflationary theory, which supposes that the primordial universe was underwent an accelerated expansion guided by a scalar field. In sequence, we introduce the standard cosmological model, which states that the universe is in accelerated expansion driving by a cosmological constant, named dark energy, which constitutes about seventy percent of the universe energy. Finally, we present a first order formalism for cosmology and discuss two model describing the standard and tachyonics dynamics for scalar field that represent the dark energy. / Neste trabalho foram abordadas soluções do tipo defeitos topológicos em teoria clássica de campos. Foram investigadas soluções topológicas e não topológicas em duas dimensões, onde também analisamos a estabilidade de algumas destas. Consideramos modelos de um e dois campos escalares reais, onde utilizamos os métodos de quadratura, BPS e das órbitas para obter soluções. Com o intuito de aplicar a teoria de campos escalares em cosmologia, introduzimos a teoria da relatividade geral, falando sobre o princípio da equivalência, equações de campo de Einstein e solução de Schwarzschild para as equações de Einstein. Abordamos alguns tópicos em cosmologia, onde enunciamos o princípio cosmológico, lei de Hubble e inflação cosmológica. Resolvemos as equações de Einstein na métrica FRW considerando o universo composto de matéria e radiação denominado modelo Big Bang quente. Com o objetivo de resolver alguns problemas de condições iniciais do universo, introduzimos a teoria inflacionária, a qual propõe que o universo primordial sofreu uma expansão acelerada guiada por um campo escalar. Após mostrar como a teoria da inflação corrige tais problemas, apresentamos o modelo cosmológico padrão, o qual afirma que o universo está em expansão acelerada e utiliza uma constante cosmológica como guia da expansão, tal constante neste cenário representa a denominada energia escura que compõe aproximadamente setenta por cento do universo. Finalmente, nós apresentamos o formalismo de primeira ordem para cosmologia e discutimos dois modelos descrevendo dinâmicas padrão e taquiônica para o campo escalar, representando a energia escura.
30

In Their Own Voice: African American Females In STEM Succeeding Against The Odds

Gillison, Alesia N. 28 March 2023 (has links)
No description available.

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