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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.
371

SAT-based answer set programming

Lierler, Yuliya 29 September 2010 (has links)
Answer set programming (ASP) is a declarative programming paradigm oriented towards difficult combinatorial search problems. Syntactically, ASP programs look like Prolog programs, but solutions are represented in ASP by sets of atoms, and not by substitutions, as in Prolog. Answer set systems, such as Smodels, Smodelscc, and DLV, compute answer sets of a given program in the sense of the answer set (stable model) semantics. This is different from the functionality of Prolog systems, which determine when a given query is true relative to a given logic program. ASP has been applied to many areas of science and technology, from the design of a decision support system for the Space Shuttle to graph-theoretic problems arising in zoology and linguistics. The "native" answer set systems mentioned above are based on specialized search procedures. Usually these procedures are described fairly informally with the use of pseudocode. We propose an alternative approach to describing algorithms of answer set solvers. In this approach we specify what "states of computation" are, and which transitions between states are allowed. In this way, we define a directed graph such that every execution of a procedure corresponds to a path in this graph. This allows us to model algorithms of answer set solvers by a mathematically simple and elegant object, graph, rather than a collection of pseudocode statements. We use this abstract framework to describe and prove the correctness of the answer set solver Smodels, and also of Smodelscc, which enhances the former using learning and backjumping techniques. Answer sets of a tight program can be found by running a SAT solver on the program's completion, because for such a program answer sets are in a one-to-one correspondence with models of completion. SAT is one of the most widely studied problems in computational logic, and many efficient SAT procedures were developed over the last decade. Using SAT solvers for computing answer sets allows us to take advantage of the advances in the SAT area. For a nontight program it is still the case that each answer set corresponds to a model of program's completion but not vice versa. We show how to modify the search method typically used in SAT solvers to allow testing models of completion and employ learning to utilize testing information to guide the search. We develop a new SAT-based answer set solver, called Cmodels, based on this idea. We develop an abstract graph based framework for describing SAT-based answer set solvers and use it to represent the Cmodels algorithm and to demonstrate its correctness. Such representations allow us to better understand similarities and differences between native and SAT-based answer set solvers. We formally compare the Smodels algorithm with a variant of the Cmodels algorithm without learning. Abstract frameworks for describing native and SAT-based answer set solvers facilitate the development of new systems. We propose and implement the answer set solver called SUP that can be seen as a combination of computational ideas behind Cmodels and Smodels. Like Cmodels, solver SUP operates by computing a sequence of models of completion of the given program, but it does not form the completion. Instead, SUP runs the Atleast algorithm, one of the main building blocks of the Smodels procedure. Both systems Cmodels and SUP, developed in this dissertation, proved to be competitive answer set programming systems. / text
372

Borel Determinacy and Metamathematics

Bryant, Ross 12 1900 (has links)
Borel determinacy states that if G(T;X) is a game and X is Borel, then G(T;X) is determined. Proved by Martin in 1975, Borel determinacy is a theorem of ZFC set theory, and is, in fact, the best determinacy result in ZFC. However, the proof uses sets of high set theoretic type (N1 many power sets of ω). Friedman proved in 1971 that these sets are necessary by showing that the Axiom of Replacement is necessary for any proof of Borel Determinacy. To prove this, Friedman produces a model of ZC and a Borel set of Turing degrees that neither contains nor omits a cone; so by another theorem of Martin, Borel Determinacy is not a theorem of ZC. This paper contains three main sections: Martin's proof of Borel Determinacy; a simpler example of Friedman's result, namely, (in ZFC) a coanalytic set of Turing degrees that neither contains nor omits a cone; and finally, the Friedman result.
373

Gene-pair based statistical methods for testing gene set enrichment in microarray gene expression studies

Zhao, Kaiqiong 16 September 2016 (has links)
Gene set enrichment analysis aims to discover sets of genes, such as biological pathways or protein complexes, which may show moderate but coordinated differentiation across experimental conditions. The existing gene set enrichment approaches utilize single gene statistic as a measure of differentiation for individual genes. These approaches do not utilize any inter-gene correlations, but it has been known that genes in a pathway often interact with each other. Motivated by the need for taking gene dependence into account, we propose a novel gene set enrichment algorithm, where the gene-gene correlation is addressed via a gene-pair representation strategy. Relying on an appropriately defined gene pair statistic, the gene set statistic is formulated using a competitive null hypothesis. Extensive simulation studies show that our proposed approach can correctly control the type I error (false positive rate), and retain good statistical power for detecting true differential expression. The new method is also applied to analyze several gene expression datasets. / October 2016
374

Absolute Continuity and the Integration of Bounded Set Functions

Allen, John Houston 05 1900 (has links)
The first chapter gives basic definitions and theorems concerning set functions and set function integrals. The lemmas and theorems are presented without proof in this chapter. The second chapter deals with absolute continuity and Lipschitz condition. Particular emphasis is placed on the properties of max and min integrals. The third chapter deals with approximating absolutely continuous functions with bounded functions. It also deals with the existence of the integrals composed of various combinations of bounded functions and finitely additive functions. The concluding theorem states if the integral of the product of a bounded function and a non-negative finitely additive function exists, then the integral of the product of the bounded function with an absolutely continuous function exists over any element in a field of subsets of a set U.
375

Analýza nahrávky ve vybraných utkáních volejbalu Ligy mistrů 2009 /2010 / Analysis of the set in chosen volleyball matches in Champion League 2009/2010

Ulč, Jan January 2011 (has links)
In this work we have tried to make analysis of specialized activity of setter's sets. Our research observed five setters from the best european club competitions- Michal Sládeček, Raphael Vieira de Oliveiro, Lukasz Zygadl, Sergey Grankyn and Simon Fischer. The analysis of their game performance in six Champion League matches 2009/2010 was focused on quality of the set, its frequency into particular directions and kind of the set from two different qualities of reception. We also concentrated on laying-out of sets and their qualities until the first sequence. For gathering objective information we used a method of indirect observation. We also had video recordings of all six chosen Champion League matches 2009/2010.Conclusions and results of the thesis could be used during the training process, mainly to improve game activities of an individual. In concrete terms we focused on the position of a setter who works as a prolonged hand of a trainer and is influenced by his commands from the point of view of tactics. This work could refer to the right and tactical laying-out of sets in matches and importance of quality of the set. Creating the metodology for recording and evaluation of the set which is dependent on the previous reception helped us evaluate the individual game performance of the setters in their...
376

Génération de maillage à partir d'images 3D en utilisant l'adaptation de maillage anisotrope et une équation de réinitialisation / Direct multiphase mesh generation from 3D images using anisotropic mesh adaptation and a redistancing equation

Zhao, Jiaxin 03 March 2016 (has links)
Ces dernières années, les techniques d'imagerie ont fait l'objet de beaucoup d'améliorations. Elles permettent de fournir des images numériques 2D ou 3D précises de zones parfois invisibles à l’œil nu. Ces techniques s'appliquent dans de nombreux domaines comme l'industrie cinématographique, la photographie ou l'imagerie médicale... Dans cette thèse, l'imagerie sera utilisée pour effectuer des simulations numériques en la couplant avec un solveur éléments finis. Nous présenterons, en premier lieu, la morphologie mathématique et la méthode d'immersion d'image. Elles permettront l'extraction d'informations permettant la transformation d'une image dans un maillage exploitable. Puis, une méthode itérative d'adaptation de maillage basée sur un estimateur d'erreur sera utilisée afin de construire un maillage optimal. Ainsi, un maillage sera construit uniquement avec les données d'une image. Nous proposerons également une nouvelle méthodologie pour construire une fonction régulière a l'aide d'une méthode de réinitialisation de la distance signée. Deux avantages sont à noter : l'utilisation de la fonction régularisée permet une bonne adaptation de maillage. De plus, elle est directement utilisable par le solveur éléments finis. Les simulations numériques sont donc réalisées en couplant éléments finis stabilisés, adaptation de maillage anisotrope et réinitialisation. L'objectif de cette thèse est donc de simplifier le calcul numérique à partir d'image, d'améliorer la précision numérique, la construction d'un maillage automatique et de réaliser des calculs numériques parallèles efficaces. Les applications envisagées peuvent être dans le domaine médical, de la physique des matériaux ou du design industriel. / Imaging techniques have well improved in the last decades. They may accurately provide numerical descriptions from 2D or 3D images, opening perspectives towards inner information, not seen otherwise, with applications in different fields, like medicine studies, material science or urban environments. In this work, a technique to build a numerical description under the mesh format has been implemented and used in numerical simulations when coupled to finite element solvers. Firstly, mathematical morphology techniques have been introduced to handle image information, providing the specific features of interest for the simulation. The immersed image method was then proposed to interpolate the image information on a mesh. Then, an iterative anisotropic mesh adaptation operator was developed to construct the optimal mesh, based on the estimated error concerning the image interpolation. The mesh is thus directly constructed from the image information. We have also proposed a new methodology to build a regularized phase function, corresponding to the objects we wish to distinguish from the image, using a redistancing method. Two main advantages of having such function are: the gradient of the regularized function performs better for mesh adaptation; the regularized function may be directly used for the finite element solver. Stabilized finite element flow and advection solvers were coupled to the constructed anisotropic mesh and the redistancing function, allowing its application to multiphase flow numerical simulations. All these developments have been extended in a massively parallel context. An important objective of this work is the simplification of the image based computations, through a modified way to segment the image and by coupling all to an automatic way to construct the mesh used in the finite element simulations.
377

A importância da incerteza macroeconômica para prever o consumo nos EUA / The importance of macroeconomic uncertainty to forecast US consumption

Levy, Bruno do Prado Costa 04 December 2017 (has links)
O objetivo deste trabalho é averiguar a existência de incremento de acurácia nos modelos de previsão das diferentes categorias de consumo das famílias nos EUA ao se considerar a incerteza macroeconômica como variável explicativa. Grande parte dos trabalhos existentes na literatura consideram o índice da pesquisa de sentimento do consumidor da Universidade de Michigan ou a confiança do consumidor do Conference Board como variáveis alternativas capazes de antecipar o comportamento do consumo das famílias. Como se tratam de entrevistas que podem carregar parcialidade nas respostas e que não estão estritamente ligadas aos movimentos da incerteza, propomos a utilização de uma medida que agregue econometricamente as variações da incerteza macroeconômica, de tal forma que nossos modelos contenham informações mais refinadas sobre o comportamento da economia. A proposta e comparar o poder preditivo de quatro grupos de modelos econométricos para três horizontes temporais distintos (um, três e doze meses à frente). Para tal, consideramos a utilização do método de avaliação conjunta de superioridade preditiva, o Model Confidence Set. Os resultados obtidos apontam para a existência de contribuição preditiva ao incluir uma variável de incerteza macroeconômica para a previsão do consumo, em especial nos modelos de previsão um passo (mês) à frente. / The aim of this work is to verify the existence of an increase in forecasting models accuracy of different categories of household consumption in USA when considering macroeconomic uncertainty as an explanatory variable. Much of the work in the literature considers the University of Michigan Consumer Sentiment Survey Index or Conference Board Consumer Confidence as alternative variables capable of anticipating household consumption behavior. Because these indexes are composed of interviews that may carry a certain amount of bias in responses and are not strictly linked to the movements of uncertainty, we propose the use of a measure that econometrically adds variations of macroeconomic uncertainty, so that our models contain more refined information on the behavior of the economy. The proposal is to compare the predictive power of four groups of econometric models for three distinct time horizons (one, three and twelve months ahead). For this, we consider the use of the joint evaluation method of predictive superiority, Model Confidence Set. The results obtained point to the existence of a predictive contribution by including a macroeconomic uncertainty variable for consumption forecast, especially in the one step (month) ahead forecast models.
378

Operacionalização e resultados da aplicação do core set resumido de 0 a 18 anos da Classificação Internacional de Funcionalidade, Incapacidade e Saúde para crianças e jovens com paralisia cerebral / Operation and results of common brief ICF core set for children and youth with cerebral palsy aged 0 to 18 years

Oliveira, Rafaela Pichini de 11 April 2017 (has links)
Objetivo: aplicação do core set resumido genérico da CIFCJ para crianças e jovens de 0 a 18 anos com paralisia cerebral em um grupo de pacientes, através de um instrumento baseado no próprio core set, que operacionalize a coleta de dados funcionais. Métodos: Para algumas categorias, foi possível traçar uma relação entre o que se desejava avaliar e instrumentos escolhidos através de revisão da literatura. Nestes casos, as alternativas de resposta desses instrumentos foram agrupadas de forma que satisfizessem os critérios dos qualificadores da CIFCJ. Nos casos em que isso não fosse possível criou-se uma tabela de correspondência para cada item. Todos os pacientes foram classificados de acordo com o sistema de classificação da função motora grossa (GMFCS). Foram avaliados 33 pacientes dos ambulatórios e do Centro de Reabilitação de neurologia infantil do Hospital das Clínicas de Ribeirão Preto, divididos em 3 grupos, de acordo com sua faixa etária, e desenvolvidas tabelas para descrever os qualificadores de cada componente. Os dados do questionário do core set resumido de 0 a 18 anos da CIFCJ-PC foram inseridos em bancos de dados, digitados em planilha do Excel, e a análise descritiva simples deu-se através do programa estatístico SPSS. Resultados: Para cinco categorias foi possível utilizar escalas sem necessidade de perguntas auxiliares. A avaliação realizada apenas por perguntas objetivas, ocorreu em um item de funções do corpo, em três domínios de atividades e participação, e em todos os oito descritores do componente Fatores ambientais. A idade dos participantes variou entre 4 meses e 18 anos, com maior frequência (33%) de pacientes GMFCS III. A frequência de alguma forma de problema nas funções intelectuais foi de 75%, variando entre 63-81% nos três grupos etários. A Sensação de dor (b280) obteve a menor prevalência de deficiências de algum grau, existindo em maior número no grupo de 0 a 6 anos. Encontramos 91% das crianças e jovens avaliados apresentando limitação em algum grau para deslocar-se por diferentes locais (d460). Os principais facilitadores foram Família imediata (e310) (91%), Produtos e tecnologias para uso pessoal na vida diária (e115) (85%) e Serviços, políticas e sistemas de saúde (e580) (82%). A maior barreira entre os fatores ambientais foram Produtos e tecnologias usados em projeto, arquitetura e construção de edifícios (e150). Conclusão: O core set resumido da CIFCJ para crianças e jovens com paralisia cerebral de 0 a 18 anos permite gerar um perfil funcional dos pacientes com esta condição de saúde e identifica as áreas a serem mais bem trabalhadas para cada indivíduo. Aponta ainda as influências, deficiências e barreiras comuns a maioria desses indivíduos, podendo ajudar a diagnosticar problemas na área de saúde, economia e serviço social. / Objective: To apply the common brief ICF-CY core set for children and youth with cerebral palsy in a group of patients, through instruments based on the core set itself, that operationalize the data collection in functioning. Methods: For some categories, it was possible to correlate the domains and an instrument selected through literature review. In these cases, the response alternatives were grouped to satisfy the criteria of the ICF-CY qualifiers. When this was not possible, we created a correlation for each item. All patients were classified according to GMFCS. Thirty-three patients from the outpatient clinics and the Children\'s Neurology Rehabilitation Center (CER) of the Hospital das Clínicas de Ribeirão Preto (HCRP) were divided into three groups, according to their age group. Tables were developed to describe the qualifiers of each component. Data from the ICF-CY common brief core set for children and youth with CP were entered into databases, typed in an Excel spreadsheet, and the simple descriptive analysis was done through the SPSS statistical program. Results: For five categories, it was possible to use scales without the need for auxiliary questions. The evaluation performed with only objective questions, occurred in an item of the component functions of the body, in three domains of activities and participation, and in all eight descriptors of the Environmental factors component. The participants aged from 4 months to 18 years, with a greater frequency (33%) of GMFCS III patients. The prevalence of some sort of problem in intellectual functions was 75%, varying between 63-81% in the three age groups. Sensation of pain (b280) obtained the lowest prevalence of deficiencies, existing in a greater number in the group of 0 to 6 years. We found 91% of the children and young people evaluated, showing some degree of limitation for Moving around different locations (d460). The main facilitators were Immediate family (e310) (91%), Products and technology for personal use in daily living (e115) (85%) and Health services, systems and policies (e580) (82%). The biggest barrier in environmental factors was Design, construction and building products and technology of buildings for public use (e150). Conclusion: common brief ICF-CY core set for children and youth with cerebral palsy is very useful to generate a functional profile for patients with CP, and to identify the areas to be better worked for each individual. This core set also points out influences, deficiencies and barriers that are common for most of these children, and should help on identifying problems in health, economy and social services.
379

Estudo in vitro e in vivo de novos compostos: com alvo-específico (hnRNP K e SET) ou com ação na mitocôndria para uso como antitumoral em carcinoma oral ou como citoprotetor em célula não-tumoral / Studies in vitro and in vivo novel compounds: with target-specific (hnRNP K and SET) or the mitochondrion action for use as antitumor in oral carcinoma cell or as cytoprotection in non-tumor

Goto, Renata Nishida 12 September 2017 (has links)
Os avanços na compreensão da biologia das neoplasias de cabeça e pescoço têm aberto novas direções na ciência. As pesquisas estão sendo direcionadas para o desenvolvimento de terapias com alvos moleculares específicos, os quais são úteis tanto na predição dos tratamentos, quanto na seleção de pacientes que podem responder a uma determinada terapia com base nas alterações moleculares dos tumores. As proteínas hnRNP K e SET, recentemente identificadas como superexpressas em câncer de cabeça e pescoço, representam um novo e atrativo alvo terapêutico para esse tipo de câncer. As mitocôndrias também tem sido objeto de estudo, pois participam nos processos de morte celular por apoptose, e estão envolvidas na sobrevivência celular. Neste estudo avaliamos os efeitos in vitro e in vivo em carcinoma oral e em célula não-tumoral, de novos compostos com alvo-específico (hnRNP K e SET) ou com ação na mitocôndria, para aplicação tanto como antitumoral, como citoprotetor. A citotoxicidade dos compostos foi avaliada pelo método de resazurina nas linhagens tumorais de carcinoma de células escamosas de cabeça e pescoço (HN13, HN12, HN6 e CAL27). Os compostos 11 e 17, alvos específicos da proteína hnRNP K, apresentaram baixa citotoxicidade; o peptídeo OP449, alvo específico da proteína SET, e o composto YV-241, com ação na mitocôndria, apresentaram alta citotoxicidade, com valores de IC50 5,11 e 7,77 ?M, respectivamente. OP449 alterou as proteínas reguladas por SET e reduziu a proliferação das células tumorais no modelo de xenoenxerto ortotópico em camundongo BALB/ c nude; os resultados, porém, não foram significativos. A associação de OP449 com FTY720 promoveu um efeito sinérgico significativo (CID<0,7) na linhagem celular HN12 e reduziu os tumores do xenoenxerto no dorso em camundongos BALB/c nude. O composto YV-241 alterou o potencial de membrana mitocondrial das células tumorais e aumentou o número de mitocôndrias, observado por microscopia eletrônica de transmissão e por microscopia confocal, reduziu proteínas envolvidas com vias de sinalização de sobrevivência, proliferação, ciclo celular e angiogênese, e induziu apoptose com o envolvimento da mitocôndria. Além disso, o composto reduziu os tumores do modelo de xenoenxerto. O possível efeito citoprotetor do composto JM-E-H foi observado na linhagem NOK-SI, por meio da regulação da via de sinalização de HIF-1?. Portanto, OP449 + FTY720 e o composto YV-241 apresentam potencial terapêutico contra carcinoma oral, e o composto JM-E-H, potencial efeito citoprotetor / Advances in understanding the biology of head and neck cancer have opened new directions in science. Research is being directed at the development of therapies with specific molecular targets that are useful in predicting treatments or in selecting patients who may respond to a particular molecular therapy based on molecular changes of the tumors. The hnRNP K and SET proteins, recently identified as overexpressed in head and neck cancer, represent a new and attractive therapeutic target for this type of cancer. Mitochondria have also been the object of study, since they participate in the processes of cell death by apoptosis, and are involved in cell survival. In this work we evaluated the in vitro and in vivo effects in oral carcinoma and non-tumor cell of new compounds with specific target (hnRNP K and SET) or with action in mitocondria, for application either as antitumor or cytoprotectant. The cytotoxicity of the compounds was evaluated by the resazurin method in head and neck squamous cell carcinoma cell lines (HN13, HN12, HN6 and CAL27). Compounds 11 and 17, specific targets of hnRNP K protein, showed low cytotoxicity; the peptide OP449, specific target of SET protein, and compound YV-241, acting on mitochondria, showed high cytotoxicity, with IC50 values of 5.11 and 7. 77?M, respectively. OP449 altered SET-regulated proteins and decreased proliferation of tumor cells in the orthotopic xenograft model in BALB/c nude mouse. The results, however, were not significant. The association of OP449 with FTY720 caused a significant synergistic effect (CID <0.7) on HN12 cell line, and decreased the xenograft tumors. The YV-241 compound altered mitochondrial membrane potential of tumor cells and increased the number of mitochondria, observed by transmission electron microscopy and by confocal microscopy, reduced proteins involved with signaling pathways for survival, proliferation, cell cycle and angiogénesis, and induced apoptosis with the involvement of mitochondria. In addition,the compound reduced tumors of the xenograft model. The possible cytoprotective effect of the compound JM-E-H was observed in the NOK-SI lineage through the regulation of HIF-1? signaling pathway. Therefore, OP449 + FTY720 and compound YV-241 show therapeutic potential against oral carcinoma, and the compound JM-E-H, potential cytoprotective effect
380

Reconstruction 3D de vaisseaux sanguins / 3D reconstruction of blood vessels

Al Moussawi, Ali 17 December 2014 (has links)
Ce travail concerne la reconstruction 3D de vaisseaux sanguins à partir de coupes transversales en nombre éventuellement réduit. Si des données sont manquantes, une reconstruction cohérente avec un réseau de vaisseaux est obtenue. Cette approche permet en outre de limiter les interventions humaines lors du traitement des images des coupes transversales 2D. Sachant que les images utilisées sont obtenues par scanner,la difficulté est de connecter les vaisseaux sanguins entre deux coupes espacées pour obtenir un graphe qui correspond au cœur des vaisseaux. En associant les vaisseaux sanguins sur les coupes à des masses à transporter, on construit un graphe solution d’un problème de transport ramifié. La reconstruction 3D de la géométrie résulte des données 2D d’imagerie issues des différentes coupes transversales et du graphe. La géométrie 3D des vaisseaux sanguins est représentée par la donnée d’une fonction Level Set définie en tout point de l’espace dont l’iso-valeur zéro correspond aux parois des vaisseaux. On s’intéresse ensuite à résoudre numériquement le modèle de Navier-Stokes en écoulement incompressible sur un maillage cartésien inclus dans la géométrie reconstruite. Ce choix est motivé par la rapidité d’assemblage du maillage et des opérateurs discrets de dérivation, en vue d’éventuelles déformation des vaisseaux. L’inadaptation du maillage avec l’interface de la géométrie amène à considérer une condition limite modifiée permettant un calcul consistant des contraintes aux parois. / This work concerns the 3D reconstruction of blood vessels from a limited number of 2D transversal cuts obtained from scanners. If data are missing, a coherentreconstruction with a vessel network is obtained. This approach allows to limit human interventions in processing images of 2D transversal cuts. Knowing that the images used are obtained by scanner, the difficulty is to connect the blood vessels between some widely spaced cuts in order to produce the graph corresponding to the network of vessels. We identify the vessels on each trnasversal cut as a mass to be transported, we construct a graph solution of a branched transport problem. At this stage, we are able to reconstruct the 3D geometry by using the 2D Level Set Functions given by the transversal cuts and the graph information. The 3D geometry of blood vessels is represented by the data of the Level Set function defined at any point of the space whose 0-level corresponds to the vessel walls. The resulting geometry is usually integrated in a fluid mechanic code solving the incompressible Navier-Stokes equations on a Cartesian grid strictly included in a reconstructed geometry. The inadequacy of the mesh with the interface of the geometry is overcomed thanks to a modified boundary condition leading to an accurate computation of the constraints to the walls.

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