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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.
71

On a remarkable set of words in the mapping class group /

Cadavid, Carlos Alberto, January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 61-63). Available also in a digital version from Dissertation Abstracts.
72

Bayesian simultaneous intervals for small areas : an application to mapping mortality rates in U.S. Health Service areas

Erhardt, Erik Barry. January 2004 (has links)
Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Poisson-Gamma Regression; MCMC; Bayesian; Small Area Estimation; Simultaneous Inference; Statistics Includes bibliographical references (p. 61-67).
73

Design synthesis of multistable equilibrium systems

King, Carey Wayne, Beaman, Joseph J. Campbell, Matthew I., January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: Joseph J. Beaman, Jr. and Matthew Campbell. Vita. Includes bibliographical references.
74

Density evolution in systems with slow approach to equilibrium

Nelson, Kevin Taylor, Turner, Jack S., Driebe, Dean J. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: Jack S. Turner and Dean J. Driebe. Vita. Includes bibliographical references and index.
75

Leis de escala associadas à quebra de simetria da distribuição de energia em um conjunto de sistemas dinâmicos: aplicações em mapeamentos discretos / Scaling laws associated with a symmetry-break in the energy distribution in a set of dynamical systems: application to discrete mappings

Silva, Matheus Palmero [UNESP] 01 September 2017 (has links)
Submitted by MATHEUS PALMERO SILVA null (matheuspalmero@gmail.com) on 2017-10-23T17:38:42Z No. of bitstreams: 1 Palmero-Dissertação-Final+Ficha.pdf: 7872041 bytes, checksum: 4aced1a4e65b4822d5cad50fbfb47973 (MD5) / Rejected by Luiz Galeffi (luizgaleffi@gmail.com), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: Inserir o número do processo de financiamento FAPESP nos agradecimentos da tese/dissertação. Corrija estas informações e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2017-10-26T16:22:04Z (GMT) / Submitted by MATHEUS PALMERO SILVA null (matheuspalmero@gmail.com) on 2017-10-26T16:38:06Z No. of bitstreams: 1 Palmero-Dissertação-Final+Ficha.pdf: 7872232 bytes, checksum: 5757e6926325d1f74438fff3cd26d5e0 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-10-26T16:55:48Z (GMT) No. of bitstreams: 1 silva_mp_me_rcla.pdf: 7872232 bytes, checksum: 5757e6926325d1f74438fff3cd26d5e0 (MD5) / Made available in DSpace on 2017-10-26T16:55:48Z (GMT). No. of bitstreams: 1 silva_mp_me_rcla.pdf: 7872232 bytes, checksum: 5757e6926325d1f74438fff3cd26d5e0 (MD5) Previous issue date: 2017-09-01 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Nesta dissertação, investigamos propriedades estatísticas de alguns sistemas dinâmicos descritos por mapeamentos discretos nas proximidades de duas transições: (i) integrabilidade para não integrabilidade e; (ii) crescimento limitado de energia para crescimento ilimitado de energia (aceleração de Fermi). O foco principal está na descrição do comportamento da distribuição de probabilidade da velocidade/energia das partículas em dinâmica caótica. A quebra de simetria da distribuição de probabilidade leva a uma escala adicional àquelas já conhecidas na literatura e, com este estudo, acreditamos que a quebra de simetria também possa explicar um fenômeno que já vem sendo observado em mapeamentos discretos. Fenômeno este, até então descrito apenas fenomenologicamente, teve sua primeira observação na publicação seminal de investigação de leis de escala em mapeamentos discretos no periódico Phys. Rev. Let. 93, 014101 (2004), de Edson D. Leonel, Peter V. E. McClintock e Jafferson K. L. Silva. Nossa contribuição para o problema está no desenvolvimento de descrições analíticas e verificações numéricas, baseadas em um estudo sistemático do comportamento difusivo das trajetórias caóticas no espaço de fases dos sistemas dinâmicos de interesse. / In this dissertation, we investigate statistical properties of some dynamical systems described by discrete mappings near two types of transitions: (i) integrability to non-integrability; (ii) limited to unlimited diffusion in energy (Fermi acceleration). The main goal is to describe the behaviour of the probability density of the velocity/energy for a set of particles moving in a chaotic dynamics. The break of symmetry in the probability distribution leads to an additional scaling to those are already known in the literature and, with this study, we believe that the symmetry break might also explain a well-known phenomenon observed for discrete mappings. This phenomenon, it has been reported so far phenomenologically. A first observation in an area-preserving mapping was in a letter published in Phys. Rev. Let. 93, 014101 (2004), authored by Edson D. Leonel, Peter V. E. McClintock and Jafferson K. L. Silva. Our contribution to the problem is on the development of an analytical approach and numerical verifications, based essentially on a systematic study of the diffusive behaviour of chaotic trajectories on the phase space of dynamical systems of interest. / FAPESP: 2014/27260-5
76

Deformações de cônicas e quádricas por operadores lineares / Deformations of conics and quadrics under linear mappings

Tavares, Fabiano Pinto 05 August 2008 (has links)
Orientadores: Sueli Irene Rodrigues Costa, Simão Nicolau Stelmastchuk / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-10T23:29:23Z (GMT). No. of bitstreams: 1 Tavares_FabianoPinto_M.pdf: 877532 bytes, checksum: 0081c7182db3aab71edcbe274822bea5 (MD5) Previous issue date: 2008 / Resumo: Neste trabalho focalizamos a deformação de cônicas e quádricas por transformações lineares. Deduzimos de forma explícita os autovalores e autovetores ortonormais de matrizes reais 2 x 2 e 3 x 3, para os quais não há quase referências na literatura e nem incorporação nos programas computacionais de cálculo simbólico usuais. Esta determinação levou -nos a estudar um pouco da história da resolução das equações de terceiro grau e das condições e formulações das raízes reais destas. Os resultados foram utilizados na determinação explícita das deformações por transformações lineares de cônicas e quádricas, sendo estas discutidas em termos de características das matrizes associadas / Abstract: We discuss here the deformations of conics and quadrics under linear mappings. We set explicitly the eingenvalues and the orthonormal eigenvectors of real symmetric 2 X 2 and 3 X 3 matrices. These expressions are scarce in the literature and not incorporated in symbolic calculus software. The determination of those eigenvalues leaded us to the study of the solution of third degree equations and some of related historical aspects with focus on conditions and expressions for their real solutions Those results are used in the exact determination of the linear deformation of conics and quadrics in terms of the characteristics of their associated matrices / Mestrado / Geometria Topologia / Mestre em Matemática
77

Spectral shaping and distance mapping with permutation sequences

Ouahada, Khmaies Taher 04 June 2012 (has links)
D.Ing. / In this thesis we combined two techniques, namely a spectral shaping technique and a distance-preserving mapping technique to design new codes with both special spectrum shaping and error correction capabilities, in order to overcome certain communication problems like those that occur in a power-line communication channel. A new distance-preserving mapping construction based on graph theory is firstly presented. The k-cube graph construction from binary sequences to permutation sequences reached the upper bound on the sum of the Hamming distances for certain lengths of the permutation sequences and achieves the same sum of the Hamming distances as the best previously published constructions for most of the rest of the lengths. The k-cube graph construction is considered to be a simple and easy construction to understand the concept of mappings and especially the concept of a distance-reducing mapping.
78

Coz-related and other special quotients in frames

Matlabyana, Mack Zakaria 02 1900 (has links)
We study various quotient maps between frames which are defined by stipulating that they satisfy certain conditions on the cozero parts of their domains and codomains. By way of example, we mention that C-quotient and C -quotient maps (as defined by Ball and Walters- Wayland [7]) are typical of the types of homomorphisms we consider in the initial parts of the thesis. To be little more precise, we study uplifting quotient maps, C1- and C2-quotient maps and show that these quotient maps possess some properties akin to those of a C-quotient maps. The study also focuses on R - and G - quotient maps and show, amongst other things, that these quotient maps coincide with the well known C - quotient maps in mildly normal frames. We also study quasi-F frames and give a ring-theoretic characterization that L is quasi-F precisely when the ring RL is quasi-B´ezout. We also show that quasi-F frames are preserved and reflected by dense coz-onto R -quotient maps. We characterize normality and some of its weaker forms in terms of some of these quotient maps. Normality is characterized in terms of uplifting quotient maps, -normally separated frames in terms of C1-quotient maps and mild normality in terms of R - and G -quotient maps. Finally we define cozero complemented frames and show that they are preserved and reflected by dense z#- quotient maps. We end by giving ring-theoretic characterizations of these frames. / Mathematical Science / D. Phil. (Mathematics)
79

Quantifying Lingua-Palatal Contact Patterns of Fricative Productions by Non-native Students Enrolled in a University German Language Course: An Electropalatography Study

Lester, Kate Erin 01 June 2017 (has links)
Electropalatography (EPG) is a computer-based tracking system designed to provide real-time visual biofeedback of articulatory contacts occurring during speech production. Historically, EPG technology has proven functional within the treatment and assessment of speech disorders however, application of EPG technology to assist in second language learning has remained limited. The present thesis is part of a larger study examining the effectiveness of using EPG as an advanced instructional tool for assisting second language (L2) learners of German. Fricative productions ([ç], [x], /s/, and /∫/) within real words were gathered from 12 native English speakers enrolled in a second semester university level course to learn German. Speech productions from student participants were compared against native German speakers' productions collected in a previous study, using electrode mappings, percentages of regional contact, and center of gravity measures. These measures revealed different patterns of palatal contact between fricative sounds, between individual subjects, and cross-linguistically. Fricative sound mappings varied visually as speakers generally produced [ç] and [x] with significantly less palatal contact than when producing /s/ and /∫/. Variation across individual subjects was identified as some produced sounds with nearly no posterior palatal contact while others produced sounds asymmetrically or with decreased overall contact. Cross-linguistic differences were apparent as non-native German speakers frequently contacted greater numbers of electrodes with greater force, compared to the natives. It is anticipated that the information included in this thesis will provide insights into the role of EPG technology as an instructional tool for L2 learners.
80

Untersuchungen von Hintergrundwissen zur Verbesserung von semantischen Mappings

Jacob, Marcel 12 February 2018 (has links)
Diese Bachelorarbeit soll eine Strategie testen, mit der es möglich ist, die Ergebnisse eines gegebenen Schema Mappings zu verbessern, indem die Defizite beim Erkennen von den genannten Beziehungen zumindest teilweise beseitigt werden. Damit dieses Ziel erreicht werden kann, sind verschiedene Schritte notwendig. Zunächst müssen die grundlegenden Begriffe definiert werden, die in unmittelbaren Zusammenhang mit der Vorbereitung, der praktischen Umsetzung und der Evaluation stehen und daher unerlässlich für das Verstehen der Gesamtproblematik sind.

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