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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.
151

On merit functions, error bounds, minimizing and stationary sequences for nonsmooth variational inequality problems. / CUHK electronic theses & dissertations collection

January 2005 (has links)
First, we study the associated regularized gap functions and the D-gap functions and compute their Clarke-Rockafellar directional derivatives and the Clarke generalized gradients. Second, using these tools and extending the works of Fukushima and Pang (who studied the case when F is smooth), we present results on the relationship between minimizing sequences and stationary sequences of the D-gap functions, regardless the existence of solutions of (VIP). Finally, as another application, we show that, under the strongly monotonicity assumption, the regularized gap functions have fractional exponent error bounds, and thereby we provide an algorithm of Armijo type to solve the (VIP). / In this thesis, we investigate a nonsmooth variational inequality problem (VIP) defined by a locally Lipschitz function F which is not necessarily differentiable or monotone on its domain which is a closed convex set in an Euclidean space. / Tan Lulin. / "December 2005." / Adviser: Kung Fu Ng. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6444. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 79-84) and index. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
152

Poincaré recurrence, measure theoretic and topological entropy. / CUHK electronic theses & dissertations collection

January 2007 (has links)
Consider a dynamical system which is positively expansive and satisfies the condition of specification. We further study the topological entropy of the level sets for local Poincare recurrence, i.e. the recurrence spectrum. It turns out that the spectrum is quite irrational as any level set has the same (topological) entropy as the whole system. The erratic recurrence behavior of the orbits brings chaos. For the system concerned, we show that it contains a Xiong chaotic set C which is large in the sense that the intersection of any non-empty open set with C has the same topological entropy as the whole system. The ergodic average can be regarded as a certain recurrence average. We give multifractal analysis of the generalized spectrum for ergodic average, which incorporates the information of the set of divergence points. Note that the set of divergence points for Poincare recurrence or ergodic average has measure zero with respect to any invariant measure. (A Xiong chaotic set may has measure zero with respect to some invariant measures with full support.) The above results support the point of view that small set unobservable in measure may account for the anomalous chaotic behavior of the whole system. / The thesis is on the recurrence and chaotic behavior of a dynamical system. Let the local Poincare recurrence rate at a point be defined as the exponential rate of the first return time of the orbit into its neighborhoods defined by the Bowen metric. Given any reference invariant probability measure mu, we show that the rate equals to the local entropy of mu a.e. Hence, the integration of the rate is exactly the (measure theoretic) entropy of the measure mu. / Shu, Lin. / "January 2007." / Adviser: Ka-Sing Lau. / Source: Dissertation Abstracts International, Volume: 68-08, Section: B, page: 5286. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 83-91). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
153

Sequências espectrais e aplicações para módulos / Spectral sequences and applications to modules

Wellington Marques de Souza 30 January 2017 (has links)
As sequências espectrais foram criadas por Jean Leray num campo de concentração durante a Segunda Guerra Mundial motivado por problemas inerentes à Topologia Algébrica. Num primeiro momento, surge como uma ferramenta para auxiliar no cálculo da cohomologia de um feixe. Porém, Jean-Louis Koszul apresenta uma formulação puramente algébrica para tais sequencias, que consiste basicamente no cálculo da homologia de um complexo total associado a um complexo duplo. Concentraremos nosso trabalho nas definições e resultados que nos permitem demonstrar os seguintes resultados conhecidos da Álgebra usando sequências espectrais: o Lema dos Cinco, o Lema da Serpente, Balanceamento para o Funtor Tor, Mudança de Base para o Funtor Tor e o Teorema dos Coeficientes Universais. Apresentamos, ao final do trabalho, uma generalização que nos permite entender melhor os funtores derivados à esquerda: as Sequências Espectrais de Grothendieck. / Spectral sequences were created by Jean Leray in a concentration camp during World War II motivated by problems of Algebraic Topology. At first, it appears as a tool to assist in calculating the cohomology of a sheaf. However, Jean-Louis Koszul presents a purely algebraic formulation for these sequences, which basically consists in calculating a total of homology complex associated with a double complex. We will focus our work on the definitions and results that allow us to demonstrate known results of algebra using spectral sequences: The Five Lemma, The Snake Lemma, Balancing of functor Tor, Base Change for Tor and Universal Coefficient Theorem. We present, at the end of this work, a generalization that allows us to better understand the left derivative functors: the Spectral Sequence of Grothendieck.
154

Computação inteligente no estudo de variantes de hemoglobina / Intelligent computation applied to the study of hemoglobin variants

Sousa, Thaís Helena Samed e 29 October 2004 (has links)
A evolução in vitro é um método laboratorial criado para a evolução de moléculas, principalmente de proteínas. Por meio de mutações, o método busca novas propriedades de moléculas, objetivando criar novas proteínas e, com isso, intensificar o estudo e a cura de doenças, pelo desenvolvimento de novos fármacos. O grande desafio na evolução in vitro é criar o maior número possível de moléculas de proteínas que atinjam propriedades desejadas, uma vez que apenas uma fração infinitesimal das diversidades geradas utilizando-se seqüências de DNA é aproveitada. Para se obter moléculas com funcionalidade adequada por meio dessa técnica, é requerido muito tempo e aporte financeiro. Com o objetivo de avaliar computacionalmente a funcionalidade de proteínas variantes a partir das seqüências de aminoácidos buscando reduzir o custo e o tempo desprendido em laboratório, este trabalho propõe o uso de técnicas de computação inteligentes (evolução in silicio), baseadas em aprendizado de máquina e computação evolutiva. Para o emprego de técnicas de AM, bancos de dados com elevado número de informações são fundamentais. Neste sentido, escolheu-se investigar as moléculas mutantes de hemoglobina, uma vez que a quantidade de informações disponíveis sobre a mesma é bastante extensa na literatura. Os resultados obtidos mostram que é possível desenvolver algoritmos eficientes para determinar a funcionalidade de variantes de hemoglobina. Com esses resultados, busca-se contribuir no desenvolvimento de técnicas de evolução dirigida com suporte computacional / In vitro evolution is a laboratorial method developed to molecule evolution mainly proteins. By producing mutations, this method looks for new molecule properties, aiming achieve new proteins for the development of drugs for diseases. The great challenge of in vitro evolution is the development of the highest possible number of molecules that reaches desired properties. This objective is a great challenge to be transposed, since only one infinitesimal fraction of generated proteins using DNA sequencies is usefull to obtain molecules with the desired function. Besides high financial support and time are required to apply this technique. With the objective of evaluating computacionaly and functionality of proteins mutants starting from aminoacids sequences looking for to reduce the cost and the time loosened at laboratory, this work proposes the use of intelligent computation techniques based on learning of it conspires and evolutionary computation. On the other hand, when machine learning techniques are used, it is fundamental to access data mining with high number of information. In order to reduce these difficulties, this work proposes a machine learning (ML) based on approach to evaluate computationaly hemoglobin variants. ML techniques require, in general, large data base. In order to supply this requirement, hemoglobin variants were used because there is a large number of hemoglobin variants available in the literature. The obtained results shown that is possible to develop efficient algorithms to determine hemoglobin variant function. These results can contribute for development of molecule evolution techniques
155

Movement preparation and execution in Huntington's and Parkinson's diseases

Johnson, Katherine A. (Katherine Anne), 1973- January 2001 (has links)
Abstract not available
156

Theobroma cacao L. nucleotide sequence of cocoa seed vicilin and patterns of expression of cocoa seed vicilin and albumin protease inhibitor genes /

McHenry, Lauren. January 1992 (has links) (PDF)
Thesis (Ph. D.)--Pennsylvania State University, 1992. / Includes bibliographical references.
157

Methods for vision-based robotic automation

Viksten, Fredrik January 2005 (has links)
<p>This thesis presents work done within the EC-founded project VISATEC. Due to the different directions of the VISATEC project this thesis has a few different threads.</p><p>A novel presentation scheme for medium level vision features applied to range sensor data and to image sequences. Some estimation procedures for this representation have been implemented and tested. The representation is tensor based and uses higher order tensors in a projective space. The tensor can hold information on several local structures including their relative position and orientation. This information can also be extracted from the tensor.</p><p>A number of well-known techniques are combined in a novel way to be able to perform object pose estimation under changes of the object in position, scale and rotation from a single 2D image. The local feature used is a patch which is resampled in a log-polar pattern. A number of local features are matched to a database and the k nearest neighbors vote an object state parameters. This most probable object states are found through mean-shift clustering.</p><p>A system using multi-cue integration as a means of reaching a higher level of system-level robustness and a higher lever of accuracy is developed and evaluated in an industrial-like-setting. The system is based around a robotic manipulator arm with an attached camera. The system is designed to solve parts of the bin-picking problem. The above mentioned 2D technique for object pose estimation is also evaluated within this system.</p>
158

Ideals finitament generats i decreixement de funcions analítiques i acotades

Pau Plana, Jordi 19 June 2001 (has links)
No description available.
159

Automatic Sequences and Decidable Properties: Implementation and Applications

Goc, Daniel January 2013 (has links)
In 1912 Axel Thue sparked the study of combinatorics on words when he showed that the Thue-Morse sequence contains no overlaps, that is, factors of the form ayaya. Since then many interesting properties of sequences began to be discovered and studied. In this thesis, we consider a class of infinite sequences generated by automata, called the k-automatic sequences. In particular, we present a logical theory in which many properties of k-automatic sequences can be expressed as predicates and we show that such predicates are decidable. Our main contribution is the implementation of a theorem prover capable of practically characterizing many commonly sought-after properties of k-automatic sequences. We showcase a panoply of results achieved using our method. We give new explicit descriptions of the recurrence and appearance functions of a list of well-known k-automatic sequences. We define a related function, called the condensation function, and give explicit descriptions for it as well. We re-affirm known results on the critical exponent of some sequences and determine it for others where it was previously unknown. On the more theoretical side, we show that the subword complexity p(n) of k-automatic sequences is k-synchronized, i.e., the language of pairs (n, p(n)) (expressed in base k) is accepted by an automaton. Furthermore, we prove that the Lyndon factorization of k-automatic sequences is also k-automatic and explicitly compute the factorization for several sequences. Finally, we show that while the number of unbordered factors of length n is not k-synchronized, it is k-regular.
160

Highly Non-Convex Crossing Sequences

McConvey, Andrew January 2012 (has links)
For a given graph, G, the crossing number crₐ(G) denotes the minimum number of edge crossings when a graph is drawn on an orientable surface of genus a. The sequence cr₀(G), cr₁(G), ... is said to be the crossing sequence of a G. An equivalent definition exists for non-orientable surfaces. In 1983, Jozef Širáň proved that for every decreasing, convex sequence of non-negative integers, there is a graph G such that this sequence is the crossing sequence of G. This main result of this thesis proves the existence of a graph with non-convex crossing sequence of arbitrary length.

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