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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.
271

Desenvolvimento de um sensor de temperatura inteligente - compensação em tempo real dos efeitos de convecção, acumulação e radiação / Development of an intelligent temperature sensor – on-line compensation of the convection, accumulation and radiation effects

Oliveira, Juliana de 13 April 2006 (has links)
Esta tese apresenta o desenvolvimento de uma técnica de processamento numérico capaz de reconstruir o sinal da temperatura do processo original a partir do sinal distorcido, atrasado e ruidoso, medido através de uma sonda intrusiva. Uma técnica de regularização foi adotada para contornar o mau condicionamento do modelo numérico inverso da equação de transdução para obter o sinal do processo, que considera o acúmulo térmico e as transferências de calor convectivo e radiativo entre o meio e o sensor térmico. O método dos mínimos quadrados simplificado foi implementado como técnica de regularização, por ser um método rápido e possuir um código computacional pequeno, permitindo, obter os dados em tempo real e desenvolver um sensor térmico inteligente. Testes numéricos demonstraram as discrepâncias introduzidas pela inércia térmica, convecção e radiação, bem como a extrema sensibilidade da presença de ruídos quando o problema inverso é resolvido. Testes experimentais foram conduzidos para validar o algoritmo de reconstrução sob condições práticas com sinais obtidos por um termopar encapsulado / This thesis presents the development of a numerical processing technique capable of reconstructing the original process temperature signal from distorted, late and noisy measured signal obtained from an intrusive probe. A regularization technique was adopted to palliate the ill conditioning of the inverse numerical model of the transduction equation to obtain the process signal, which considers thermal accumulation and convective and radiative heat transfers between the medium and the thermal sensor. The simplified least square method was implemented as the regularization technique, because it is a fast method and results in a small computational code, which produces on-line information and allow the development an intelligent temperature sensor. Numerical tests demonstrated the discrepancies introduced by thermal inertia, convection and radiation, as well as the extreme sensitivities to the presence of noise when solving the inverse problem. Experimental tests were carried out to validate the reconstruction algorithm under realistic experimental conditions with the signals obtained by the sheathed thermocouple
272

Jardim Pantanal : atores e interesses, desalento e esperança / Jardim Pantanal: actors and interests, discouragement and hope

Silva, Amanda Sousa da 27 October 2016 (has links)
Na cidade de São Paulo a habitação regular e digna para a população de baixa renda é tema complexo. É grande o número de loteamentos irregulares e favelas na cidade. É sabido que morar em condições precárias trazem diversos prejuízos à qualidade de vida e a dignidade das pessoas que habitam nessas condições. Este trabalho busca a reflexão sobre o espaço urbano a partir da comunidade do Jardim Pantanal, considerando necessária a discussão sobre os conflitos por espaço, a ideia de território e de comunidade, movimentos sociais e remoções. Para tal, foi utilizado como caminho metodológico o mapeamento dos atores e interesses identificados no Jardim Pantanal. A ação dos atores apontaram possibilidades de reflexões e diversos esclarecimentos a respeito da própria dinâmica do espaço estudado. É também abordada a situação fundiária do Jardim Pantanal, bem como o processo de luta dos moradores e movimentos sociais e entidades para que a Regularização Fundiária ocorra. A Regularização Fundiária é o procedimento pelo qual se busca tornar lícita a ocupação da terra nos casos em que o acesso àquele bem tenha ocorrido de modo irregular. Os princípios da Regularização Fundiária visam à ampliação do acesso a terra urbanizada pela população de baixa renda, com prioridade para sua permanência na área ocupada, assegurados o nível adequado de habitabilidade e a melhoria das condições de sustentabilidade urbanística, social e ambiental. Para conhecer o Jardim Pantanal é também necessário ter ciência das constantes inundações, enchentes e remoções já ocorridas no bairro e que continuam como possibilidade de acontecer. São apresentados os planos e projetos que visam a intervenção no Jardim Pantanal, tais como: plano de Manejo das Várzeas do rio Tietê, o Parque Várzeas do Tietê e o projeto urbanístico Renova São Paulo. São discutidas as possíveis consequências do processo de implantação de cada projeto. Foi identificado neste trabalho que o Jardim Pantanal apesar de ser conhecido, de modo geral, como um local difícil de viver, perigoso e com altos índices de vulnerabilidade social, possui também diversas potências e fatores positivos que fazem com que os diversos atores, ainda que com interesses diferentes, permaneçam envolvidos na dinâmica deste espaço. Desalento e esperança parecem marcar a história dos moradores e do território do Jardim Pantanal, onde os interesses dos atores envolvidos e as intervenções realizadas mudam, às vezes definitivamente, a trajetória de uma comunidade / In the city of São Paulo the regular and decent housing for low-income population is a complex subject. There are a great number of irregular settlements and slums in the city. As is well known that to live in precarious conditions may bring many losses to the quality of life and to the dignity of those people who have been living in these conditions. This work seeks to make a reflection on the urban space of Jardim Pantanal community, considering the necessary discussion on the conflicts for space, the idea of territory and community, social movements, removals and urban dispossession. For such, it was used as a methodological way the mapping of actors and interests identified in the Jardim Pantanal. The action of the actors pointed out possibilities of reflections and various clarifications regarding on its own dynamics of the studied space. It also addressed the agrarian situation of Jardim Pantanal, as well as the struggle process of the residents and social movements and entities for the Land Regularization works out. The Land Regularization is the procedure by which it seeks to convert lawful occupation of land in cases in which the access of that good has occurred in irregular terms. These principles of Regularization aimed at the increasing access to the urbanized land for the low-income population, priority for their stay in the occupied area, ensuring the adequate level of housing and improvement of urban, social and environmental sustainability. To know the Jardim Pantanal is also necessary to be aware of the constant flooding, floods and removals that have already occurred in the neighborhood and that continue as a possibility to happen. The plans and projects are presented aimed at intervention in the Jardim Pantanal, such as: the Tiete River Floodplains Management Plan, the Tiete Wetlands Park and the urban project Renew São Paulo. The possible consequences of the implementation of each design process have been discussed. It was identified in this work that the Jardim Pantanal, despite being generally known as a difficult place to live, dangerous and with high levels of social vulnerability, also has several potencies and positive factors that make the various actors still that with different interests, remain involved in the dynamics of this space. Discouragement and hope seem to mark the history of the residents and the Jardim Pantanal territory where the interests of stakeholders and interventions change, sometimes permanently, the trajectory of a community
273

A legitimação de posse na dimensão registrária da regularização fundiária / The legitimacy of tenure in the register dimension of land regularization

Khuri, Naila de Rezende 09 February 2017 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-02-16T12:31:17Z No. of bitstreams: 1 Naila de Rezende Khuri.pdf: 3608760 bytes, checksum: ba831ca89be3135e5d532c18fb3b46b0 (MD5) / Made available in DSpace on 2017-02-16T12:31:17Z (GMT). No. of bitstreams: 1 Naila de Rezende Khuri.pdf: 3608760 bytes, checksum: ba831ca89be3135e5d532c18fb3b46b0 (MD5) Previous issue date: 2017-02-09 / The purpose of this study is to study the legitimization of tenure regulated by Law n. 11.977 of 2009, with emphasis on the registration dimension of land regularization of informal settlements occupied by low income population. The registration dimension aims at the titling of the occupants of these settlements with the premise of conferring legal security to the possession. The paper deals with the problem of the housing deficit that gave rise to informal settlements and land regularization as an instrument of solution in the light of the right to decent housing and the right to a just city. Finally, the steps of land regularization before the Real Estate Registry and the interface with the ownership legitimation are discussed / O presente trabalho tem por finalidade o estudo do instituto da legitimação de posse, regulado pela Lei n. 11.977, de 2009, com ênfase na dimensão registrária da regularização fundiária dos assentamentos informais ocupados por população de baixa renda. A dimensão registrária visa à titulação dos ocupantes desses assentamentos com a premissa de conferir segurança jurídica à posse. O trabalho aborda a problemática do déficit habitacional que deu origem aos assentamentos informais e a regularização fundiária como um instrumento de solução à luz do direito à moradia digna e ao direito à cidade justa. Por fim, abordam-se as etapas da regularização fundiária perante o Registro de Imóveis e a interface com a legitimação da posse
274

Usucapião coletiva urbana e regularização fundiária em favelas paulistanas

Chaccur, Ricardo Cotrim 29 August 2014 (has links)
Made available in DSpace on 2016-03-15T19:34:12Z (GMT). No. of bitstreams: 1 Ricardo Cotrim Chaccur.pdf: 3042642 bytes, checksum: 91fd921ab009eb79d59ac1bbeba8d321 (MD5) Previous issue date: 2014-08-29 / This dissertation aims to analyze the institution of collective urban adverse possession as an instrument of urban policy to promote land tenure regularization and urbanization of favelas in São Paulo. In Brazil, currently, the law provides some mechanisms for the realization of the right to social housing, through the acquisition of land for the purpose of social inclusion of people living in poor or substandard dwellings and therefore scope for developing citizenship. The right to housing is a social and human right, as recognized by Art. 6, caput, of the Federal Constitution of 1988 and the Habitat Agenda, organized by the United Nations Conference on Human Settlements - Habitat II, held in Instambul in 1996. And yet, the need to overcome the problem of land in slums and squatter settlements located in major urban centers, makes relevant the present work, in order to identify the causes that led to the agrarian conflict in the country, the problems arising from these areas and that reflect on the lives of urban dwellers as well as an analysis of one of the legal instruments to deal with this problem. / A presente dissertação objetiva analisar o instituto da usucapião coletiva urbana, enquanto instrumento de Política Urbana para promover a regularização fundiária e urbanização das favelas na cidade de São Paulo. No Brasil, atualmente, a legislação dispõe de alguns mecanismos para a efetivação do direito social de moradia, por meio da aquisição da propriedade imobiliária, com a finalidade de inclusão social dos habitantes que residem em moradias precárias ou subnormais e, consequentemente, alcance do desenvolvimento da cidadania. O direito à moradia é, um direito social e humano, conforme reconhecido pelo art. 6º, caput, da Constituição Federal de 1988 e pela Agenda Habitat, organizada pela Conferência das Nações Unidas sobre Assentamentos Humanos Habitat II, realizada em Instambul, em 1996. E, ainda, a necessidade de superação do problema fundiário nos assentamentos irregulares e favelas localizadas em importantes centros urbanos brasileiros, faz pertinente o presente trabalho, a fim de identificar as causas que originaram o conflito fundiário no País, os problemas decorrentes dessas áreas e que refletem na vida dos habitantes urbanos, bem como uma analise de um dos instrumentos jurídicos de tratamento deste problema.
275

Determinação de espectros de energia de elétrons clínicos do eixo central a partir de curvas de porcentagem de dose em profundidade de feixes largos / Determination of central axis energy spectra of clinical electron beam from percentage depth dose curves of broad beams

Jorge Homero Wilches Visbal 15 August 2018 (has links)
Em radioterapia, o espectro de energia é o componente mais importante dos feixes de elétrons. Espectros de energia de elétrons são relevântes para o cálculo acurado da dose, aplicações do sistema de planejamento e simulações realistas. Reconstrução inversa consiste na derivação do espectro de energia de elétrons a partir de curvas de porcentagem de dose em profundidade utilizando um apropiado modelo matemático. Reconstrução inversa é considerada a melhor dentre muitas abordagens porque: i) não requer nenhum equipamento suplementar ou do conhecimento detalhado da geometria e composição do cabeçote do acelerador; ii) equipamentos para a medição de curvas de porcentagem de dose em profundidade estão disponíveis em qualquer clínica e iii) é computacionalmente rápida. Neste trabalho, usou-se o método de reconstrução inversa baseado na sinergia recozimento simulado generalizado-regularização de Tikhonov. A validação da reconstrução foi realizada através do índice gama sob critérios clínicos de aceitação restritivos. Resultados mostraram que os espectros de energia reconstruídos reproduzem com precisão a porcentagem de dose em profundidade clínica bem como valores de dose fora do eixo central. Assim, concluí-se que o método empregado é ecaz para reconstruir espectros de energia que representam efetivamente espectros de energia do acelerador que atingem na supercie do fantoma. Consequentemente, sob certos limites, eles poderiam auxiliar em simulações realistas do tratamento. / In radiotherapy, energy spectrum is the most critical component of any electron beam. Knowledge of energy spectrum is important for accurate dose calculation, treatment planning applications and realistic simulations. Inverse reconstruction derives energy spectrum from the measured percentage depth dose using an appropriate mathematical model. There are several advantages to using inverse reconstruction: i) it does not require any supplementary equipment or detailed knowledge of the geometry head and composition; ii) the equipment for measurement of the percentage depth dose is standard and already available in any clinic and iii) it is computationally fast. In this work, we used the inverse reconstruction method based on the synergy simulated annealing generalized-Tikhonov regularization. Validation of inverse reconstruction was done by comparing the measured and reconstructed percentage depth dose via the gamma index. Results show the reconstructed electron energy spectra accurately reproduce the clinical dose percentage as well as o-axis dose values. Therefore, it was concluded that the method employed is eective to reconstruct energy spectra that eectively represent accelerator energy spectra reaching the phantom surface. Consequently, under certain limits, they could aid in realistic simulations of treatment.
276

Programa de regularização fundiária sustentável de assentamentos irregulares de São Bernardo do Campo: avanços e desafios ao processo de regularização fundiária no âmbito da política habitacional municipal / Program of sustainable environmental regularization of irregular settings of São Bernardo do Campo: advances and challenges to the process of environmental regularization in the framework of municipal housing policy

Brandimiller, Tatiana Urbanovik 19 April 2017 (has links)
A pesquisa pretende identificar e analisar criticamente os avanços trazidos e os desafios enfrentados na implementação do Programa de Regularização Fundiária Sustentável no município de São Bernardo do Campo, estado de São Paulo. Ao abordar a regularização fundiária, a pesquisa busca compreender o seu papel como política pública estratégica na promoção do acesso à moradia e à cidade por parte da população de baixa renda. A intenção do trabalho é contribuir para construção de um panorama crítico às diferentes compreensões e proposições de atuação sobre a Regularização Fundiária de Interesse Social. Para tanto, problematiza a questão em suas diversas acepções e concepções, abordando criticamente e relacionando-a às diferentes correntes de pensamento sobre o tema. Além do aporte conceitual e da literatura específica, contribui para a pesquisa as experiências profissionais vividas pela autora ao longo dos últimos cinco anos na implementação dessa política pública no município de São Bernardo do Campo. / The research aims to critically identify and analyse the advances brought and the challenges faced in the implementation of a Sustainable Land Tenure Regularization Program in the municipality of São Bernardo do Campo, state of São Paulo. When addressing land tenure regularization, the research seeks to understand its role as a public policy strategic in the promotion of access to housing and to the city by the low-income population. The intention of the paper is to contribute to the construction of a panorama critical to the different understandings and propositions of action about the Land Tenure Regularization of Social Interest. To do so, it problematizes the issue in its various meanings and conceptions, critically approaching and relating it to the different lines of thought on the subject. Besides the conceptual addition and specific literature, contributes to the research the professional experiences of the author over the past five years in the implementation of this public policy in the municipality of São Bernardo do Campo.
277

Data Poisoning Attacks on Linked Data with Graph Regularization

January 2019 (has links)
abstract: Social media has become the norm of everyone for communication. The usage of social media has increased exponentially in the last decade. The myriads of Social media services such as Facebook, Twitter, Snapchat, and Instagram etc allow people to connect with their friends, and followers freely. The attackers who try to take advantage of this situation has also increased at an exponential rate. Every social media service has its own recommender systems and user profiling algorithms. These algorithms use users current information to make different recommendations. Often the data that is formed from social media services is Linked data as each item/user is usually linked with other users/items. Recommender systems due to their ubiquitous and prominent nature are prone to several forms of attacks. One of the major form of attacks is poisoning the training set data. As recommender systems use current user/item information as the training set to make recommendations, the attacker tries to modify the training set in such a way that the recommender system would benefit the attacker or give incorrect recommendations and hence failing in its basic functionality. Most existing training set attack algorithms work with ``flat" attribute-value data which is typically assumed to be independent and identically distributed (i.i.d.). However, the i.i.d. assumption does not hold for social media data since it is inherently linked as described above. Usage of user-similarity with Graph Regularizer in morphing the training data produces best results to attacker. This thesis proves the same by demonstrating with experiments on Collaborative Filtering with multiple datasets. / Dissertation/Thesis / Masters Thesis Computer Science 2019
278

<em>η'</em> Decay to π<sup>+</sup>π<sup>-</sup>π<sup>+</sup>π<sup>−</sup>

Jafari, Ehsan 01 January 2018 (has links)
With the use of chiral theory of mesons [1], [2] we evaluate the decay rate of η′ → π+π−π+π−. Our theoretical study of this problem is different from the previous theo- retical study [3] and our predicted result is in a good agreement with the experiment. In this chiral theory we evaluate Feynman diagrams up to one loop and the decay rate is calculated with the use of triangle and box diagrams. The ρ0 meson includes in both type of diagrams as a resonance state. Divergent integrals in the loop calculations are regularized with the use of n-dimensional ’t Hooft-Veltman regularization technique. At the last step to obtain the decay rate, the phase space integral has been calculated.
279

Measuring Linguistic and Cultural Evolution Using Books and Tweets

Gray, Tyler 01 January 2019 (has links)
Written language provides a snapshot of linguistic, cultural, and current events information for a given time period. Aggregating these snapshots by studying many texts over time reveals trends in the evolution of language, culture, and society. The ever-increasing amount of electronic text, both from the digitization of books and other paper documents to the increasing frequency with which electronic text is used as a means of communication, has given us an unprecedented opportunity to study these trends. In this dissertation, we use hundreds of thousands of books spanning two centuries scanned by Google, and over 100 billion messages, or ‘tweets’, posted to the social media platform, Twitter, over the course of a decade to study the English language, as well as study the evolution of culture and society as inferred from the changes in language. We begin by studying the current state of verb regularization and how this compares between the more formal writing of books and the more colloquial writing of tweets on Twitter. We find that the extent of verb regularization is greater on Twitter, taken as a whole, than in English Fiction books, and also for tweets geotagged in the United States relative to American English books, but the opposite is true for tweets geotagged in the United Kingdom relative to British English books. We also find interesting regional variations in regularization across counties in the United States. However, once differences in population are accounted for, we do not identify strong correlations with socio-demographic variables. Next, we study stretchable words, a fundamental aspect of spoken language that, until the advent of social media, was rarely observed within written language. We examine the frequency distributions of stretchable words and introduce two central parameters that capture their main characteristics of balance and stretch. We explore their dynamics by creating visual tools we call ‘balance plots’ and ‘spelling trees’. We also discuss how the tools and methods we develop could be used to study mistypings and misspellings, and may have further applications both within and beyond language. Finally, we take a closer look at the English Fiction n-gram dataset created by Google. We begin by explaining why using token counts as a proxy of word, or more generally, ‘n-gram’, importance is fundamentally flawed. We then devise a method to rebuild the Google Books corpus so that meaningful linguistic and cultural trends may be reliably discerned. We use book counts as the primary ranking for an n-gram and use subsampling to normalize across time to mitigate the extraneous results created by the underlying exponential increase in data volume over time. We also combine the subsampled data over a number of years as a method of smoothing. We then use these improved methods to study linguistic and cultural evolution across the last two centuries. We examine the dynamics of Zipf distributions for n-grams by measuring the churn of language reflected in the flux of n-grams across rank boundaries. Finally, we examine linguistic change using wordshift plots and a rank divergence measure with a tunable parameter to compare the language of two different time periods. Our results address several methodological shortcomings associated with the raw Google Books data, strengthening the potential for cultural inference by word changes.
280

Graph-based Latent Embedding, Annotation and Representation Learning in Neural Networks for Semi-supervised and Unsupervised Settings

Kilinc, Ismail Ozsel 30 November 2017 (has links)
Machine learning has been immensely successful in supervised learning with outstanding examples in major industrial applications such as voice and image recognition. Following these developments, the most recent research has now begun to focus primarily on algorithms which can exploit very large sets of unlabeled examples to reduce the amount of manually labeled data required for existing models to perform well. In this dissertation, we propose graph-based latent embedding/annotation/representation learning techniques in neural networks tailored for semi-supervised and unsupervised learning problems. Specifically, we propose a novel regularization technique called Graph-based Activity Regularization (GAR) and a novel output layer modification called Auto-clustering Output Layer (ACOL) which can be used separately or collaboratively to develop scalable and efficient learning frameworks for semi-supervised and unsupervised settings. First, singularly using the GAR technique, we develop a framework providing an effective and scalable graph-based solution for semi-supervised settings in which there exists a large number of observations but a small subset with ground-truth labels. The proposed approach is natural for the classification framework on neural networks as it requires no additional task calculating the reconstruction error (as in autoencoder based methods) or implementing zero-sum game mechanism (as in adversarial training based methods). We demonstrate that GAR effectively and accurately propagates the available labels to unlabeled examples. Our results show comparable performance with state-of-the-art generative approaches for this setting using an easier-to-train framework. Second, we explore a different type of semi-supervised setting where a coarse level of labeling is available for all the observations but the model has to learn a fine, deeper level of latent annotations for each one. Problems in this setting are likely to be encountered in many domains such as text categorization, protein function prediction, image classification as well as in exploratory scientific studies such as medical and genomics research. We consider this setting as simultaneously performed supervised classification (per the available coarse labels) and unsupervised clustering (within each one of the coarse labels) and propose a novel framework combining GAR with ACOL, which enables the network to perform concurrent classification and clustering. We demonstrate how the coarse label supervision impacts performance and the classification task actually helps propagate useful clustering information between sub-classes. Comparative tests on the most popular image datasets rigorously demonstrate the effectiveness and competitiveness of the proposed approach. The third and final setup builds on the prior framework to unlock fully unsupervised learning where we propose to substitute real, yet unavailable, parent- class information with pseudo class labels. In this novel unsupervised clustering approach the network can exploit hidden information indirectly introduced through a pseudo classification objective. We train an ACOL network through this pseudo supervision together with unsupervised objective based on GAR and ultimately obtain a k-means friendly latent representation. Furthermore, we demonstrate how the chosen transformation type impacts performance and helps propagate the latent information that is useful in revealing unknown clusters. Our results show state-of-the-art performance for unsupervised clustering tasks on MNIST, SVHN and USPS datasets with the highest accuracies reported to date in the literature.

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