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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.
101

O lugar do parentesco na aliança entre um laudo antropológico e um território quilombola : análise a partir do processo de regularização fundiária do Quilombo Cambará em Cachoeira do Sul/RS

Ramos, Ieda Cristina Alves January 2009 (has links)
O presente trabalho pretende analisar, a partir do processo de regularização fundiária da Comunidade Remanescente de Quilombo Cambará em Cachoeira do Sul/RS, o lugar do parentesco na aliança entre um laudo antropológico e um território quilombola. Procurei discutir, a partir das exigências normativas relacionadas ao reconhecimento de comunidades quilombolas do Rio Grande do Sul, o estatuto do relatório antropológico nos desdobramentos da potencialização de Cambará como comunidade. Segue-se nas trilhas deixadas pelos antigos moradores na forma de taperas e de como as taperas codificam o parentesco e circunscrevem o território. Evidenciou-se, também, o modo como o parentesco sobrecodifica o território. E, por fim, se reconstituiu as implicações do processo de construção de um relatório antropológico de uma comunidade quilombola, processo esse que só se completa na aliança entre o território e o texto. Não se trata apenas de constatar o lugar mais ou menos privilegiado que a genealogia do parentesco tende a ocupar na estratégia de escrita desse tipo de relatório acadêmico sob demanda administrativa, nem, tampouco, de reafirmar o quanto o parentesco é importante na territorialização das comunidades quilombolas. A questão que norteou este trabalho pode ser mais bem definida enquanto investigação do modo como se deram a interpenetração de textos, territórios e pessoas na forma de parentesco. A pergunta de partida foi quanto ao como, o parentesco associa pessoas, territórios e textos. / This paper analyses the place of kinship in the union between an anthropological report and a quilombola territory bearing in mind the process of land regularization of Quilombo Cambará’s remaining community in Cachoeira do Sul/RS. Considering the regulatory requirements related to the recognition of quilombola communities of Rio Grande do Sul, I tried to discuss about the status of anthropological report on the steps to development Cambará as a community. In order to do this, we follow the tracks left by previous owners in the form of “taperas” and how these houses codify the kinship and circumscribe the territory. It was clear, too, how the relationship over codify the territory. And finally, the construction implications of an black community anthropological report were reconstructed – a process that is only completed in the alliance between the territory and the text. It is not only see the place more or less privileged that kinship genealogy tends to be as an writing strategy of this kind of academic report on management demand, nor, to reaffirm how important the kinship to the territory establishment of quilombola communities . The question that guided this work can best be defined as research on how texts, territories and people in the form of kinship connected to each other. The starting question was about how the kinship links people, territories and texts.
102

Quantização estocástica e a invariância de Gauge / Stochastic quantization and gauge invariance

Viana, Ricardo Luiz 15 October 1987 (has links)
Na presente dissertação fazemos um resumo das idéias fundamentais do método de Quantização Estocástica de Parisi e Wu, com aplicações a teorias de campo Escalares, de Gauge e Fermiônicas. Em particular, nós utilizamos o esquema de Regularização Analítica Estocástica no cálculo do tensor de polarização para a Eletrodinâmica Quântica com Bósons ou Fêrmions de Dirac. A influência da regularização na invariância de Gauge e estudada para ambas as teorias, e é sugerida uma extensão do método para alguns modelos supersimétricos. / In the present dissertation, we made a survey of the fundamental ideas about Parisi-Wu\'s Stochastic Quantization Method, with applications to Scalar, Gauge and Fermionic theories. In particular, we use the Analytic Stochastic Regularization Scheme to calculate the polarization tensor for Quantum Electrodynamics with bosons or Dirac Fermions. The regularization influence is studied for both theories and an extension of this method for some supersymmetrical models is suggested.
103

Luz na favela : a complexidade no processo de regularização da energia elétrica na favela Bougival, em Santo André-SP

Fournier, Anna Carolina Pires January 2014 (has links)
Orientador: Prof. Dr. Claudio Luis de Camargo Penteado / Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Energia, 2014. / A energia elétrica é um recurso indispensável para a vida nas cidades. Entretanto, seu fornecimento ainda não é universalizado e interrompe-se nas favelas. A presente pesquisa tem por objetivo principal compreender o processo de regularização da eletricidade em favelas. O objeto de estudo escolhido foi a ação realizada na favela Bougival, localizada no município de Santo André (SP), em área de responsabilidade da empresa AES Eletropaulo. Buscando como base a teoria da complexidade de Edgar Morin, propõe-se compreender o processo de regularização da energia elétrica em favelas com seus entraves, obstáculos e particularidades, dentro de uma visão complexa, integrada e sistêmica. Através de recortes metodológicos diversos, tais como as pesquisas bibliográfica e documental, observação em campo, realização de entrevistas e aplicação de questionários, destacam-se os seguintes resultados: a dificuldade no pagamento da alta tarifa de energia, a ausência de orientação aos novos consumidores de eletricidade, e o caráter técnico e unidirecional da ação. / Electricity is an essential resource for life in cities. However, its supply is still not universalized and is constantly interrupted in the slums. The main objective of this research is to understand the process of regularization of electricity in slums. The chosen object of the study was a measure taken in Bougival slum, located in the municipality of Santo André (SP), in a area under the responsibility of energy company AES Eletropaulo. By using Edgar Morin¿s theory of complexity as its basis, the study proposes understanding the process of regularization of electricity in slums, with all its obstacles and circumstances, within a complex, integrated and systemic view. Through various methodological tools, such as bibliographical and archival research, field observation, interviews and questionnaires, the study highlights the following results: the difficulty in paying a high price for energy, the lack of orientation for new consumers of electricity, and the technical and unidirectional character of the procedure.
104

Modelo Simplificado de SimulaÃÃo de ReservatÃrios. RegressÃes dos Volumes Evaporado, Vertido e Regularizado. / Simplefied Simulation Reservoir Model using evaporated, discharged and regularized volumes.

Vitor Moreira da Rocha Ponte 10 June 2008 (has links)
nÃo hà / O presente trabalho tem por objetivo identificar equaÃÃes simplificadas que permitam determinar o comportamento de reservatÃrios a partir de um reduzido nÃmero de parÃmetros. SÃo identificados quatro parÃmetros: i) coeficiente de variaÃÃo dos volumes afluentes anuais ao reservatÃrio; ii) volume adimensional do reservatÃrio, razÃo entre a capacidade de armazenamento do reservatÃrio e o volume mÃdio afluente anual ao mesmo; iii) fator de evaporaÃÃo adimensional, funÃÃo do volume mÃdio afluente anual ao reservatÃrio, dos coeficientes de forma deste reservatÃrio e da evaporaÃÃo potencial lÃquida do espelho dâÃgua, em metros; e iv) garantia, sendo esta considerada mensal ou anual. A partir destes quatro parÃmetros, sÃo determinadas equaÃÃes que permitem prever, para um determinado reservatÃrio, os volumes adimensionais: i) evaporado; ii) vertido; e iii) regularizado. Para a determinaÃÃo destas equaÃÃes sÃo utilizados dados de reservatÃrios gerados aleatoriamente. Estes reservatÃrios foram simulados, determinando os volumes adimensionais evaporado, vertido e regularizado, variÃveis estas ditas dependentes, assim como determinados os valores dos quatro parÃmetros independentes. A partir destas variÃveis dependentes e independentes, sÃo determinadas as equaÃÃes simplificadas atravÃs da tÃcnica de regressÃo linear, determinando os limites de validade e os erros inerentes à aplicaÃÃo das mesmas. Em um segundo momento, as equaÃÃes determinadas no decorrer deste trabalho sÃo validadas atravÃs da anÃlise de setenta e cindo reservatÃrios localizados no Estado da ParaÃba. Destas equaÃÃes, à possÃvel identificar, tanto o comportamento de reservatÃrios, bem como o efeito individual de cada uma das variÃveis independentes no comportamento dos mesmos. As equaÃÃes desenvolvidas nesta Tese sÃo de fÃcil aplicaÃÃo, reduzido dispÃndio de tempo e apresentam, em certa medida, erros reduzidos. / The present research identifies simplified equations capable to determine the behavior of reservoirs. It considers four independent variables: i) coefficient of variation of annual inflow; ii) dimensionless reservoir capacity; iii) dimensionless evaporation factor, function of the average annual inflow, reservoir shape coefficients and potential net evaporation; and iv) probability of failure. The dependents variables are: i) dimensionless evaporation loss volume; ii) dimensionless spill loss volume; and iii) dimensionless release volume. Initially, were used data from reservoirs generated randomly. The reservoirs dependents and independents variables values were determined after its simulation. It was used linear regression to determine the relationship between the dependents and independents variables. Limits of validity and errors were also determined. The equations determined in this research were used in seventy-five reservoirs located in the state of ParaÃba, Brazil, in order to validate them. By using the equations determined in this research, it is possible to identify: i) the behavior of reservoirs; and ii) the individual effect of each independent variable in the reservoir dependents variables. The equations developed in this thesis are easy to apply, time saving and have acceptable errors.
105

On the regularization of the recursive least squares algorithm. / Sobre a regularização do algoritmo dos mínimos quadrados recursivos.

Manolis Tsakiris 25 June 2010 (has links)
This thesis is concerned with the issue of the regularization of the Recursive Least-Squares (RLS) algorithm. In the first part of the thesis, a novel regularized exponentially weighted array RLS algorithm is developed, which circumvents the problem of fading regularization that is inherent to the standard regularized exponentially weighted RLS formulation, while allowing the employment of generic time-varying regularization matrices. The standard equations are directly perturbed via a chosen regularization matrix; then the resulting recursions are extended to the array form. The price paid is an increase in computational complexity, which becomes cubic. The superiority of the algorithm with respect to alternative algorithms is demonstrated via simulations in the context of adaptive beamforming, in which low filter orders are employed, so that complexity is not an issue. In the second part of the thesis, an alternative criterion is motivated and proposed for the dynamical regulation of regularization in the context of the standard RLS algorithm. The regularization is implicitely achieved via dithering of the input signal. The proposed criterion is of general applicability and aims at achieving a balance between the accuracy of the numerical solution of a perturbed linear system of equations and its distance from the analytical solution of the original system, for a given computational precision. Simulations show that the proposed criterion can be effectively used for the compensation of large condition numbers, small finite precisions and unecessary large values of the regularization. / Esta tese trata da regularização do algoritmo dos mínimos-quadrados recursivo (Recursive Least-Squares - RLS). Na primeira parte do trabalho, um novo algoritmo array com matriz de regularização genérica e com ponderação dos dados exponencialmente decrescente no tempo é apresentado. O algoritmo é regularizado via perturbação direta da inversa da matriz de auto-correlação (Pi) por uma matriz genérica. Posteriormente, as equações recursivas são colocadas na forma array através de transformações unitárias. O preço a ser pago é o aumento na complexidade computacional, que passa a ser de ordem cúbica. A robustez do algoritmo resultante ´e demonstrada via simula¸coes quando comparado com algoritmos alternativos existentes na literatura no contexto de beamforming adaptativo, no qual geralmente filtros com ordem pequena sao empregados, e complexidade computacional deixa de ser fator relevante. Na segunda parte do trabalho, um critério alternativo ´e motivado e proposto para ajuste dinâmico da regularização do algoritmo RLS convencional. A regularização é implementada pela adição de ruído branco no sinal de entrada (dithering), cuja variância é controlada por um algoritmo simples que explora o critério proposto. O novo critério pode ser aplicado a diversas situações; procura-se alcançar um balanço entre a precisão numérica da solução de um sistema linear de equações perturbado e sua distância da solução do sistema original não-perturbado, para uma dada precisão. As simulações mostram que tal critério pode ser efetivamente empregado para compensação de números de condicionamento (CN) elevados, baixa precisão numérica, bem como valores de regularização excessivamente elevados.
106

Intervenção para urbanização de assentamentos precários no bairro João Pessoa-PB: uma abordagem da regularização fundiária de assentamentos urbanos irregulares em áreas de preservação permanente.

Dunda, Bruno Faro Eloy 13 November 2014 (has links)
Submitted by Rosina Valeria Lanzellotti Mattiussi Teixeira (rosina.teixeira@unisantos.br) on 2016-04-12T19:03:16Z No. of bitstreams: 1 Bruno Dunda.pdf: 1731182 bytes, checksum: cd1a60df193f4d114de4f05ca05098ae (MD5) / Made available in DSpace on 2016-04-12T19:03:16Z (GMT). No. of bitstreams: 1 Bruno Dunda.pdf: 1731182 bytes, checksum: cd1a60df193f4d114de4f05ca05098ae (MD5) Previous issue date: 2014-11-13 / Most Brazilian cities, either big or medium seized, live together with informal and precarious human settlements which are located in environmentally sensitive and legally protected areas and whose solution represents one of the greatest challenges of public managers. It is estimated that more than twelve million urban homes in Brazil which are occupied by low income people are irregular. This is a real fact to be faced by the public administration, always taking into consideration that there was not a legal alternative of dwelling to the families who live illegally in the settlements. The need to regularize these informal settlements located in environmentally protected areas and, therefore, with restricted occupation to exceptional cases, places ordinary legislators and public administrators between two constitutionally sacred values: the social right to housing and the right to a balanced environment. The Legislative or administrative option for one of these two constitutional values, does not provide a satisfactory solution to face the problem of the informal and precarious settlements. By choosing only the regularization of the land ownership and ensuring legal security for residents of the informal settlements located in environmentally sensitive areas, the legislator and the public administrator would ignore people¿s diffuse right to an ecologically balanced environment which is essential to the healthy life for actual and future generations. On the other hand, a strict application of the environmental standards by vacating the area and its subsequent rebuilding would respect the obligation of preserving the environment, but would also empty the contents of the social right to housing. In this context, the regularization of settlements in permanent preservation areas, as conceived by the Brazilian law, represents the achievement of technical proportionality or the balance, in the face of the collision of two constitutionally sacred values and not as an environmental backlash. This ensures, at the same time, the consecration and the compatibility of the constitutional values which are considered here, namely, the social right to housing and the right to an ecologically balanced environment. / A grande maioria dos municípios brasileiros de médio e de grande porte convive com assentamentos humanos informais e precários, muitos dos quais localizados em áreas ambientalmente sensíveis e legalmente protegidas, cuja solução representa um dos maiores desafios do gestor público. Estima-se que mais de doze milhões de domicílios urbanos ocupados por população de baixa renda, no Brasil, são irregulares, realidade esta a ser enfrentada pela Administração Pública, levando-se sempre em consideração que, em regra, não foi reservada uma alternativa legal de moradia às famílias que vivem de forma irregular nos assentamentos precários. A necessidade de se regularizar esses assentamentos informais localizados em áreas ambientalmente protegidas e, por isso mesmo, de ocupação restringida a casos excepcionais, põe o legislador ordinário e o administrador público diante de dois valores constitucionalmente consagrados: o direito social à moradia e o direito ao meio ambiente equilibrado. A opção legislativa ou administrativa por um desses dois valores constitucionais em detrimento do outro não apresenta uma solução satisfatória para o enfrentamento do problema dos assentamentos informais e precários. Ao optarem unicamente pela regularização da posse, garantindo segurança jurídica aos moradores de assentamentos informais localizados em áreas ambientalmente sensíveis, o legislador e o administrador público ignorariam o direito difuso de todos a um meio ambiente ecologicamente equilibrado e essencial à sadia qualidade de vidas das presentes e das futuras gerações. Por outro lado, a aplicação rígida da norma ambiental mediante a desocupação da área e a sua posterior recomposição atenderia ao dever de preservação do meio ambiente, porém esvaziaria o conteúdo do direito social à moradia. Nesse contexto, a regularização fundiária de assentamentos em áreas de preservação permanente, tal como concebida pela legislação brasileira, representa a concretização da técnica da proporcionalidade ou da ponderação, ante a colisão de dois valores constitucionalmente consagrados, e não como um retrocesso ambiental, garantindo, a um só tempo, a consagração e a compatibilização de ambos os valores constitucionalmente aqui considerados, quais sejam, o direito social à moradia e o direito ao meio ambiente ecologicamente equilibrado.
107

Random neural networks for dimensionality reduction and regularized supervised learning

Hu, Renjie 01 August 2019 (has links)
This dissertation explores Random Neural Networks (RNNs) in several aspects and their applications. First, Novel RNNs have been proposed for dimensionality reduction and visualization. Based on Extreme Learning Machines (ELMs) and Self-Organizing Maps (SOMs) a new method is created to identify the important variables and visualize the data. This technique reduces the curse of dimensionality and improves furthermore the interpretability of the visualization and is tested on real nursing survey datasets. ELM-SOM+ is an autoencoder created to preserves the intrinsic quality of SOM and also brings continuity to the projection using two ELMs. This new methodology shows considerable improvement over SOM on real datasets. Second, as a Supervised Learning method, ELMs has been applied to the hierarchical multiscale method to bridge the the molecular dynamics to continua. The method is tested on simulation data and proven to be efficient for passing the information from one scale to another. Lastly, the regularization of ELMs has been studied and a new regularization algorithm for ELMs is created using a modified Lanczos Algorithm. The Lanczos ELM on average divide computational time by 20 and reduce the Normalized MSE by 14% comparing with regular ELMs.
108

A Global Linear Optimization Framework for Adaptive Filtering and Image Registration

Johansson, Gustaf January 2015 (has links)
Digital medical atlases can contain anatomical information which is valuable for medical doctors in diagnosing and treating illnesses. The increased availability of such atlases has created an interest for computer algorithms which are capable of integrating such atlas information into patient specific dataprocessing. The field of medical image registration aim at calculating how to match one medical image to another. Here the atlas information could give important hints of which kinds of motion are plausible in different locations of the anatomy. Being able to incorporate such atlas specific information could potentially improve the matching of images and plausibility of image registration - ultimately providing a more correct information on which to base health care diagnosis and treatment decisions. In this licentiate thesis a generic signal processing framework is derived : Global Linear Optimization (GLO). The power of the GLO framework is first demonstrated quantitatively in a very high performing image denoiser. Important proofs of concepts are then made deriving and implementing three important capabilities regarding adaptive filtering of vector fields in medica limage registration: Global regularization with local anisotropic certainty metric. Allowing sliding motion along organ and tissue boundaries. Enforcing an incompressible motion in specific areas or volumes. In the three publications included in this thesis, the GLO framework is shown to be able to incorporate one each of these capabilities. In the third and final paper a demonstration is made how to integrate more and more of the capabilities above into the same GLO to perform adaptive processing on relevant clinical data. It is shown how each added capability improves the result of the image registration. In the end of the thesis there is a discussion which highlights the advantage of the contributions made as compared to previous methods in the scientific literature. / Dynamic Context Atlases for Image Denoising and Patient Safety
109

Statistical inference of distributed delay differential equations

Zhou, Ziqian 01 August 2016 (has links)
In this study, we aim to develop new likelihood based method for estimating parameters of ordinary differential equations (ODEs) / delay differential equations (DDEs) models. Those models are important for modeling dynamical processes that are described in terms of their derivatives and are widely used in many fields of modern science, such as physics, chemistry, biology and social sciences. We use our new approach to study a distributed delay differential equation model, the statistical inference of which has been unexplored, to our knowledge. Estimating a distributed DDE model or ODE model with time varying coefficients results in a large number of parameters. We also apply regularization for efficient estimation of such models. We assess the performance of our new approaches using simulation and applied them to analyzing data from epidemiology and ecology.
110

Penalized methods and algorithms for high-dimensional regression in the presence of heterogeneity

Yi, Congrui 01 December 2016 (has links)
In fields such as statistics, economics and biology, heterogeneity is an important topic concerning validity of data inference and discovery of hidden patterns. This thesis focuses on penalized methods for regression analysis with the presence of heterogeneity in a potentially high-dimensional setting. Two possible strategies to deal with heterogeneity are: robust regression methods that provide heterogeneity-resistant coefficient estimation, and direct detection of heterogeneity while estimating coefficients accurately in the meantime. We consider the first strategy for two robust regression methods, Huber loss regression and quantile regression with Lasso or Elastic-Net penalties, which have been studied theoretically but lack efficient algorithms. We propose a new algorithm Semismooth Newton Coordinate Descent to solve them. The algorithm is a novel combination of Semismooth Newton Algorithm and Coordinate Descent that applies to penalized optimization problems with both nonsmooth loss and nonsmooth penalty. We prove its convergence properties, and show its computational efficiency through numerical studies. We also propose a nonconvex penalized regression method, Heterogeneity Discovery Regression (HDR) , as a realization of the second idea. We establish theoretical results that guarantees statistical precision for any local optimum of the objective function with high probability. We also compare the numerical performances of HDR with competitors including Huber loss regression, quantile regression and least squares through simulation studies and a real data example. In these experiments, HDR methods are able to detect heterogeneity accurately, and also largely outperform the competitors in terms of coefficient estimation and variable selection.

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