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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.
261

The Scottish regency of the Earl of Arran : a study of the failure of Anglo-Scottish relations /

Franklin, David Byrd. January 1900 (has links)
Texte remanié de: Th. Ph. D.--University (Ala.)--University of Alabama, 1981. / Bibliogr. p. 189-204. Index.
262

Applications of variational analysis to optimal trajectories and nonsmooth Hamilton-Jacobi theory /

Galbraith, Grant N., January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (p. 87-91).
263

Analytical study of complex quantum trajectories

Chou, Chia-chun, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2009. / Title from PDF title page (University of Texas Digital Repository, viewed on Aug. 6, 2009). Vita. Includes bibliographical references.
264

Putting Katherine Dreier into perspective modern art collecting in early 20th-century America /

Klein, Sara. Bearor, Karen A. January 2005 (has links)
Thesis (M. A.)--Florida State University, 2005. / Advisor: Karen Bearor, Florida State University, School of Visual Arts and Dance, Dept. of Art History. Title and description from dissertation home page (viewed Jan. 25, 2006). Document formatted into pages; contains vii, 62 pages. Includes bibliographical references.
265

The coupled cluster method in the Hamiltonian lattice gauge theory SU(3) glueballs in two dimensions /

Wethkamp, Vera. Unknown Date (has links) (PDF)
University, Diss., 2003--Bonn.
266

Formalismo de Hamilton-Jacobi generalizado : teorias de campos com derivadas de ordem superior /

Bertin, Mario Cezar Ferreira Gomes. January 2010 (has links)
Orientador: Bruto Max Pimentel Escobar / Banca: Dmitry Vasilevich / Banca: José Abdalla Helaÿel-Neto / Banca: Álvaro de Souza Dutra / Banca: Roldão da Rocha Júnior / Resumo: Neste trabalho apresentaremos o formalismo de Hamilton-Jacobi para sistemas singulares em teorias de campos, com foco em teorias com derivadas de ordem superior. Iniciaremos com uma análise preliminar do cálculo variacional para esses sistemas, que envolve as condições para a extremização de uma integral fundamental múltipla e a análise dos teoremas de Noether. Buscaremos seguir este caminho na construção do formalismo de Hamilton- Jacobi em forma covariante, em que nos utilizaremos da clássica abordagem de Carathéodory adaptada a teorias de campos. No terceiro capítulo, mostraremos como o formalismo pode ser construído dada a escolha de uma dinâmica relativística específica e como esta escolha nos permite tratar de sistemas singulares de forma natural. No quarto capítulo abordaremos o problema das condições de integrabilidade, análise que garantirá um método autoconsistente de análise de vínculos. Nesta análise, seremos capazes de relacionar um conjunto de geradores a simetrias da integral fundamental e um segundo tipo a uma modificação da dinâmica com a introdução de parênteses generalizados. Nos dois últimos capítulos apresentaremos aplicações deste método / Abstract: In this work we will develop the Hamilton-Jacobi formalism to singular and higher-order derivative field theories. We will begin with a preliminary approach to the variational problem concerning the search for extrema of a given fundamental integral, and the analysis of the Noether's theorems. Next, we will present a covariant Hamilton-Jacobi theory using the classical approach of Carathéodory applied to field theories. In the third chapter we will show how this formalism can be derived given a choice of relativistic dynamics, and how this choice allows us to deal with singular systems. In the fourth chapter we will address the problem of integrability conditions. This analysis will be the basic tool for a self consistent constraint analysis. We will see that we can relate a certain set of generators to symmetries of the action, as well as a second type of generators to a modification of the dynamics by means of generalized brackets. The two last chapters will be used for applications / Doutor
267

Aplicação de modelos de tempo-contínuo para escolha de portfólio ótimo

Meira, Anna Carolina Granja January 2011 (has links)
A presente dissertação expõe o ambiente em que o Problema de Merton é construído e, baseando-se na bibliografia apresentada, constrói exemplos em softwares cujas especificidades podem colaborar na clareza da resolução. O software Matlab engloba as soluções numéricas, enquanto o software Maple é responsável pela solução de equações diferenciais ordinárias e parciais de forma simbólica. Apresenta-se modificações do Problema de Merton original como exercícios para melhor esclarecer os diferentes parâmetros abordados. Na seção final é apresentada a solução de viscosidade, uma alternativa quando a função valor não apresenta características desejáveis para a análise apresentada. / This dissertation explicit the environment which Merton’s problem is built, according to the presented bibliography, exemples are built in softwares whose specificity might help to clarify the solution. The Matlab software embraces numeric solutions, while Maple software is appropriate to solve ordinary and parcial differential equations in symbolic form. Some modifications are presented to Merton’s Problem as exercise to improve understanding on the variations adopted. On final section, viscosity solutions are presented as an alternative solution for when the value function does not possess the desirables properties that allow the analysis on focus.
268

Formalismo de Hamilton-Jacobi para sistemas singulares

Teixeira, Randall Guedes [UNESP] 08 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:30Z (GMT). No. of bitstreams: 0 Previous issue date: 1996-08Bitstream added on 2014-06-13T19:32:40Z : No. of bitstreams: 1 teixeira_rg_me_ift.pdf: 565736 bytes, checksum: 47638723d76926fa1da8cc7e9ede904d (MD5) / Neste trabalho apresentamos o formalismo Hamiltoniano de Dirac para sistemas singulares, analisando inclusive a construção do gerador de transformações de gauge. A seguir discutimos brevemente a generalização, já conhecida, desse formalismo para o caso de Lagrangeanos singulares de segunda ordem fazendo também uma análise da estrutura de vínculos presente em tais teorias. Desenvolvemos então o formalismo de Hamilton-Jacobi para sistemas singulares fazendo sua generalização para Lagrangeanos de segunda ordem. Por último, ambos formalismos são aplicados à Eletrodinâmica de Podols y e os resultados obtidos são comparados. / In this work we study Dirac's Hamiltonian formulation for singular systems including the construction of the gauge transformations generator. Next we briefy discuss the generalization, already developed, of this formalism for singular second order La grangians. Besides that we also make an anlysis of the constrains structure present in such theories. Then we develop the Hamilton-Jacobi formalism for singular systems making its generalization for the case of second order Lagrangians. Finally, both formalisms are applied to Podols y's eletrodynamics and the obtained results are comparad.
269

Formalismo de Hamilton-Jacobi generalizado: teorias de campos com derivadas de ordem superior

Bertin, Mario Cezar Ferreira Gomes [UNESP] 30 April 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-30Bitstream added on 2014-06-13T20:07:08Z : No. of bitstreams: 1 bertin_mcfg_dr_ift.pdf: 756466 bytes, checksum: ce1f33918fe3aabd6f7ec3c8bae37297 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho apresentaremos o formalismo de Hamilton-Jacobi para sistemas singulares em teorias de campos, com foco em teorias com derivadas de ordem superior. Iniciaremos com uma análise preliminar do cálculo variacional para esses sistemas, que envolve as condições para a extremização de uma integral fundamental múltipla e a análise dos teoremas de Noether. Buscaremos seguir este caminho na construção do formalismo de Hamilton- Jacobi em forma covariante, em que nos utilizaremos da clássica abordagem de Carathéodory adaptada a teorias de campos. No terceiro capítulo, mostraremos como o formalismo pode ser construído dada a escolha de uma dinâmica relativística específica e como esta escolha nos permite tratar de sistemas singulares de forma natural. No quarto capítulo abordaremos o problema das condições de integrabilidade, análise que garantirá um método autoconsistente de análise de vínculos. Nesta análise, seremos capazes de relacionar um conjunto de geradores a simetrias da integral fundamental e um segundo tipo a uma modificação da dinâmica com a introdução de parênteses generalizados. Nos dois últimos capítulos apresentaremos aplicações deste método / In this work we will develop the Hamilton-Jacobi formalism to singular and higher-order derivative field theories. We will begin with a preliminary approach to the variational problem concerning the search for extrema of a given fundamental integral, and the analysis of the Noether’s theorems. Next, we will present a covariant Hamilton-Jacobi theory using the classical approach of Carathéodory applied to field theories. In the third chapter we will show how this formalism can be derived given a choice of relativistic dynamics, and how this choice allows us to deal with singular systems. In the fourth chapter we will address the problem of integrability conditions. This analysis will be the basic tool for a self consistent constraint analysis. We will see that we can relate a certain set of generators to symmetries of the action, as well as a second type of generators to a modification of the dynamics by means of generalized brackets. The two last chapters will be used for applications
270

Investigating Wasp Societies: A Historical and Epistemological Study

January 2016 (has links)
abstract: The study of wasp societies (family Vespidae) has played a central role in advancing our knowledge of why social life evolves and how it functions. This dissertation asks: How have scientists generated and evaluated new concepts and theories about social life and its evolution by investigating wasp societies? It addresses this question both from a narrative/historical and from a reflective/epistemological perspective. The historical narratives reconstruct the investigative pathways of the Italian entomologist Leo Pardi (1915-1990) and the British evolutionary biologist William D. Hamilton (1936-2000). The works of these two scientists represent respectively the beginning of our current understanding of immediate and evolutionary causes of social life. Chapter 1 shows how Pardi, in the 1940s, generated a conceptual framework to explain how wasp colonies function in terms of social and reproductive dominance. Chapter 2 shows how Hamilton, in the 1960s, attempted to evaluate his own theory of inclusive fitness by investigating social wasps. The epistemological reflections revolve around the idea of investigative framework for theory evaluation. Chapter 3 draws on the analysis of important studies on social wasps from the 1960s and 1970s and provides an account of theory evaluation in the form of an investigative framework. The framework shows how inferences from empirical data (bottom-up) and inferences from the theory (top-down) inform one another in the generation of hypotheses, predictions and statements about phenomena of social evolution. It provides an alternative to existing philosophical accounts of scientific inquiry and theory evaluation, which keep a strong, hierarchical distinction between inferences from the theory and inferences from the data. The historical narratives in this dissertation show that important scientists have advanced our knowledge of complex biological phenomena by constantly interweaving empirical, conceptual, and theoretical work. The epistemological reflections argue that we need holistic frameworks that account for how multiple scientific practices synergistically contribute to advance our knowledge of complex phenomena. Both narratives and reflections aim to inspire and inform future work in social evolution capitalizing on lessons learnt from the past. / Dissertation/Thesis / Doctoral Dissertation Biology 2016

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