O uso das ferritas de manganês zinco em fontes de potência de carregadores de bateria vem crescendo nos últimos anos, devido a suas baixas perdas magnéticas em induções da ordem de 0,2 T. Estas ferritas pertencem à categoria de ferritas moles, são óxidos ferrimagnéticos, policristalinos com estrutura cúbica tipo espinélio. Pós desse material foram compactados em prensa uniaxial e em prensa automática de produção para anel e toróide, respectivamente. Foram realizados dois ciclos de queima variando o teor de oxigênio entre 5 e 15%, no patamar de sinterização, com o propósito de avaliar seu efeito na densidade, microestrutura, perdas magnéticas em altas induções (0,2 T) e permeabilidade. Amostras sinterizadas em posições mais quentes do forno resultaram em maior densidade e maior tamanho de grão, conforme esperado, mas resultaram em maiores perdas a 25 °C. O aumento do teor de oxigênio entre 5 e 15% não alterou sistematicamente a densidade, mas resultou num pequeno aumento do tamanho de grão. Já a correlação entre teor de oxigênio e perdas foi complexa. Foi observado que existe uma temperatura de mínimo nas perdas totais por volta de 60 °C. O mesmo comportamento foi observado na curva da perda histerética, compatível com a variação da constante de anisotropia magnetocristalina (K1). Foram realizados ensaios de curvas de histerese a partir de 25 até 100 °C, a 0,2 T com o objetivo de avaliar o efeito da temperatura nas duas parcelas da perda histerética. Amostras sinterizadas a 1290 °C com a menor pressão de oxigênio apresentaram menor temperatura de mínimo de perda. As técnicas de análise química do teor de Fe2+ não foram capazes de estabelecer, inequivocamente, a esperada relação entre essa variável e o teor de oxigênio da atmosfera de sinterização. / The use of manganese zinc ferrite in power sources of battery chargers is growing, due to its low magnetic power losses at inductions around 0.2 T. These ferrites belong to the soft magnetic materials group, they are polycrystalline ferromagnetic oxides with face centered cubic structure. Powders of this material were compacted in uniaxial press and in automatic press of production, by ring and toroidal form, respectively. Two firing cycles, varying the atmosphere oxygen content between 5 and 15%, were applied to evaluate its effect on microstructure, density, magnetic losses in high induction and permeability. Samples sintered in warmer positions inside the furnace resulted in higher density and larger grain size, as expected, but higher losses at 25 °C were achieved. Increasing the atmosphere oxygen content from 5 to 15% did not alter density significantly, but resulted in a slight increase in grain size. On the other hand, the correlation between oxygen content and losses was complex. There are lower losses, at 60 °C. Similar behavior was observed with hysteresis loss, which is compatible with the change in magnetocrystalline magnetic anisotropy (K1). Measurements were performed from 25 to 100 °C, at 0.2 T, aiming at the evaluation of the effect of temperature on the two parcels of hysteresis loss. Samples sintered at 1290 °C with low atmosphere oxygen content showing a minimum on the losses versus temperature curve. The available techniques to analyze Fe2+ content were not capable of establishing, unequivocally, the expected relation between this variable and the oxygen content of the sintering atmosphere.

Made available in DSpace on 2016-04-26T20:20:34Z (GMT). No. of bitstreams: 1 Gabriel Ismael Folgado Blanco.pdf: 530665 bytes, checksum: 618b2db33377311b37378a9fa0e7cc8b (MD5) Previous issue date: 2011-11-01 / The intention of this task is to face, under the focus of de Urban Law, the practice of the property market in promoting an undertaking residential model relatively recent, that is called by several names, been however, more well-known by closed division of land into lots or closed condominiums . For that it is necessary to transit through the fields of Constitutionalist Law, Administrative Law , Civil Law, as well as the support in others fields like Urbanization and Sociology, in order to understand at minimum the urban designer and the causes that make the success of the property undertaking market that, till now ,doesn t have its legal bases properly established. The challenge that goes through the whole task is the definition of the competences between the states of the federation in order do define precisely the each one s field in the area of Urban Law, especially in relation to the parcelling out of the soil. A permanent preoccupation was to make an approach that demonstrated the effects of these divisions of land into lots models, physically isolated, under the point of view of the urban planning, the territory organization and its consequences in relation to the human being fundamental rights and its correlation with the right of the city, approaching at the same time the effects concerning to the legal security. The task tried to put in evidence some aspects of this kind of urban intervention, under the point of view of the cities s social environmental upheld development, that hasn t got from the Judiciary the due attention, which has concentrated itself in the personal relationships aspects concerning to the payment of the condominium taxes or the undertakings residents s security. The task s audacious pretension is that the showed arguments contribute to an overture of a bigger reflection concerning to the regulation about this kind of urban solution that still doesn t have a definite legal structure / O presente trabalho tem por objetivo enfrentar, sob o enfoque do Direito Urbanístico, a prática do mercado imobiliário de promoção de um modelo, relativamente recente, de empreendimento habitacional, que atende por diversos nomes, sendo, entretanto, mais conhecido por loteamentos fechados ou condomínios fechados . Para tanto, inevitável o trânsito pelos campos do Direito Constitucional, do Direito Administrativo, do Direito Civil entre outros, bem como, o socorro no campo de outras matérias como do Urbanismo e da Sociologia, de modo a minimamente entender o desenho urbano e os motivos que ensejam o sucesso mercadológico de empreendimentos imobiliários que até hoje não tem suas bases jurídicas devidamente constituídas. Desafio que transcorre todo o trabalho se apresenta na definição de competências entre os entes federativos, de modo a definir com precisão o campo de cada um na área do Direito Urbanístico, especialmente em relação ao parcelamento do solo. Uma preocupação permanente foi a de realizar uma abordagem demonstrativa dos efeitos desses modelos de loteamentos que se isolam fisicamente, sob o ponto de vista do planejamento urbano, do ordenamento territorial e suas conseqüências em face dos direitos fundamentais da pessoa humana, sua co-relação com o direito à cidade, abordando ao largo os efeitos quanto à segurança jurídica. O trabalho procurou evidenciar alguns aspectos desse tipo de intervenção urbanística, sob o ponto do desenvolvimento sócio-ambiental sustentável das cidades, olhar esse que não tem obtido por parte do Poder Judiciário a devida atenção, o qual tem se concentrado nos aspectos das relações pessoais, no que tange ao pagamento das taxas condominiais ou sob o vetor da segurança de quem reside nesses empreendimentos. A pretensão audaciosa é a de que os argumentos apresentados contribuam para a abertura de uma maior reflexão quanto à regulamentação desse tipo de solução urbanística que ainda não possui uma conformação jurídica definida

We study the relationship between subdivision rules, 3-dimensional manifolds, and circle packings. We find explicit subdivision rules for closed right-angled hyperbolic manifolds, a large family of hyperbolic manifolds with boundary, and all 3-manifolds of the E^3,H^2 x R, S^2 x R, SL_2(R), and S^3 geometries (up to finite covers). We define subdivision rules in all dimensions and find explicit subdivision rules for the n-dimensional torus as an example in each dimension. We define a graph and space at infinity for all subdivision rules, and use that to show that all subdivision rules for non-hyperbolic manifolds have mesh not going to 0. We provide an alternate proof of the Combinatorial Riemann Mapping Theorem using circle packings (although this has been done before). We provide a new definition of conformal for subdivision rules of unbounded valence, show that the subdivision rules for the Borromean rings complement are conformal and show that barycentric subdivision is almost conformal. Finally, we show that subdivision rules can be degenerate on a dense set, while still having convergent circle packings.

To this date, little research has been done evaluating the quality of wildlife habitat provided by open space in residential areas. Quality wildlife habitat for the purposes of this study is defined as those areas which contain the physical and biological characteristics necessary to support native wildlife species of the region. This thesis critiqued a wildlife habitat assessment method used in a nationwide study of residential open space for the purpose of better understanding the research conducted by the study and to inform similar, future habitat evaluations of landscapes altered by human activity to accommodate residential land use. The methodology critiqued was a low resolution, habitat based, rapid assessment. The methodology provided information on the ecological function of the open space in each development and related that information to individual wildlife species needs to provide an estimation of habitat quality. However, an increase in sampling frequency and additional data collection would have improved the assessment.

La physique de la lumière ainsi que les outils géométriques pour la Conception Assistée par Ordinateur sont à la base des logiciels de simulation des phénomènes lumineux pour la fabrication des systèmes optiques. Ce n'est pas sans difficulté que les industriels conçoivent ces logiciels dont un des principaux handicaps est que les simulations sont très coûteuses en temps. L'objectif principal de ce travail est de rechercher et développer des algorithmes de calcul plus performants. Dans un premier temps, on décrit précisément le modèle du transport des photons dans ce contexte, composé de l'équation de Boltzmann accompagné de conditions de bord, et qui, dans le cas de milieux homogènes par morceaux, se ramène à l'équation de radiosité. Ensuite, on présente les outils géométriques utilisés dans le modeleur hybride CSG (Constructive Solid Geometry) et BRep (Boundary Representation) ainsi que les algorithmes de base nécessaires à la recherche d'intersections entre des demi-droites et des objets géométriques. Puis, un tour d'horizon des méthodes d'accélération des calculs en radiométrie par localisation spatiale est présenté. En tenant compte des contraintes industrielles, une telle méthode d'accélération est alors adaptée au contexte puis développée dans un environnement logiciel existant. Des expérimentations numériques montrent l'efficacité des nouvelles bibliothèques. Enfin, une étude théorique des complexités en temps et en mémoire liées aux méthodes de localisation spatiale, faisant intervenir les sommes de Minkowski d'ensembles géométriques, débouche sur une stratégie consistant à minimiser la complexité en temps pour choisir les paramètres de localisation.

Cette thèse porte sur la restauration des signaux bruités observés sur des plans d'expérience aléatoires. Trois méthodes sont proposées. Dans les deux premières, on se ramène (soit par préconditionnement des données initiales, soit par régression polynomiale locale), à un problème de régression sur grille régulière. Des majorations asymptotiques de l'erreur d'estimation sont données pour les deux méthodes, sur des classes de fonctions holderiennes pour la première et sur des boules d'espaces de Besov pour la deuxième. La vitesse de décroissance de l'erreur est dans les deux cas très proche de la vitesse optimale. Un troisième algorithme concerne les plans d'expérience déterministes et utilise les ondelettes adaptées à la grille. Elles sont construites par des schémas de subdivision non réguliers, dont on étudie la convergence et les propriétés. Des nombreuses simulations et une étude comparative illustrent le comportement des trois algorithmes quand ils sont appliqués à des échantillons de taille finie.

L'objet de ce mémoire est l'analyse des schémas de subdivision, outil de modélisation de surface lisse multi-résolution. Nos travaux se sont tout d'abord consacrés à l'étude du comportement géométrique de ces surfaces au voisinage des sommets extraordinaires du maillage de contrôle. La géométrie d'une surface de subdivision présente un comportement complexe au voisinage de ces sommets, et ces effets parfois néfastes sont pour certains encore mal connus. Nous avons proposé un cadre d'évaluation du comportement géométrique d'une surface de subdivision à travers une mesure de qualité adaptée : le gradient de courbure absolue. Nous avons ensuite proposé un espace de visualisation adapté à l'analyse du voisinage d'un sommet extraordinaire.Celui-ci étant indépendant du schéma de subdivision utilisé, ce cadre d'analyse nous permet de les comparer. Nos travaux se sont alors portés sur une analyse fréquentielle polaire des comportements géométriques, en tenant compte de leurs caractéristiques radiales et angulaires par rapport à la topologie du voisinage d'un sommet extraordinaire. Notre analyse étend les études existantes pour l'évaluation des comportements géométriques de cet outil de modélisation. De plus, nous avons proposé un systàme de description de la phase de subdivision topologique d'un schéma de subdivision. Notre systàme prend la forme d'un codage compact et flexible, il généralise les descriptions existantes. Ce codage permet la description des phases topologiques de tous les schémas de subdivision connus, ainsi que de nombreuses autres.

Esta Tesis esta motivada por el interés en aplicar procedimientos de optimización global a problemas del mundo real. Para ello, nos hemos centrado en el problema de Coordinación Hidrotérmica de la Generación Eléctrica a Corto Plazo (llamado Problema de Generación en esta Tesis) donde la función objetivo y las restricciones no lineales son polinomios de grado como máximo cuatro. En el Problema de Generación no tenemos disponible una representación en diferencia convexa de las funciones involucradas ni tampoco es posible utilizar la estructura del problema para simplificarlo. No obstante, cuando disponemos de una función continua f(x) definida en un conjunto cerrado y no vacío S el problema puede transformarse en otro equivalente expresado mediante minimize l(z) subject to z 2 D n int. (programa d.c. canónico), donde l(z) es una función convexa (en general suele ser una función lineal) con D y C conjuntos convexos y cerrados. Una estructura matemática tal como Dnint C no resulta siempre aparente y aunque lo fuera siempre queda por realizar una gran cantidad de cálculos para expresarla de manera que se pueda resolver el problema de una manera eficiente desde un punto de vista computacional.La característica más importante de esta estructura es que aparecen conjuntos convexos y complementarios de conjuntos convexos. Por este motivo en tales problemas se pueden usar herramientas analíticas tales como subdifernciales y hiperplanos soporte. Por otro lado, como aparecen conjuntos complementarios de conjuntos convexos, estas herramientas analíticas se deben usar de una manera determinada y combinándolas con herramientas combinatorias tales como cortes por planos, Branco and bound y aproximación interior.En esta tesis se pone de manifiesto la estructura matemática subyacente en el Problema de Generación utilizando el hecho de que los polinomios son expresables como diferencia de funciones convexas. Utilizando esta propiedad describimos el problema como un programa d.c. canónico equivalente. Pero aun mas, partiendo de la estructura de las funciones del Problema de Generación es posible rescribirlo de una manera mas conveniente y obtener de este modo ventajas numéricas desde elpunto de vista de la implementación.Basándonos en la propiedad de que los polinomios homogéneos de grado 1 son un conjunto de generadores del espacio vectorial de los polinomios homogéneos de grado m hemos desarrollamos los conceptos y propiedades necesarios que nos permiten expresar un polinomio cualquiera como diferencia de polinomios convexos, También, se ha desarrollado y demostrado la convergencia de un nuevo algoritmo de optimización global (llamado Algoritmo Adaptado) que permite resolver el Problema de Generación. Como el programa equivalente no esta acotado se ha introducido una técnica de subdivisión mediante prismas en lugar de la habitual subdivisión mediante conos.Para obtener una descomposición óptima de un polinomio en diferencia de polinomios convexos, se ha enunciado el Problema de Norma Mínima mediante la introducción del concepto de Descomposición con Mínima Desviación, con lo cual obtenemos implementaciones m´as eficientes, al reducir el n´umero de iteraciones del Algoritmo Adaptado. Para resolver el problema de Norma Mínima hemos implementado un algoritmo de programación cuadrática semi-infinita utilizando una estrategia de build-up and build-down, introducida por Den Hertog (1997) para resolver programas lineales semi-infinitos, la cual usa un procedimiento de barrera logarítmica.Finalmente, se describen los resultados obtenidos por la implementación de los algoritmos anteriormente mencionados y se dan las conclusiones. / This Thesis has been motivated by the interest in applying deterministic global optimization procedures to problems in the real world with no special structures. We have focused on the Short-Term Hydrothermal Coordination of Electricity Generation Problem (also named Generation Problem in this Thesis) where the objective function and the nonlinear constraints are polynomials of degree up to four. In the Generation Problem there is no available d.c. representation of the involved functions and we cannot take advantage of any special structure of the problem either. Hence, a very general problem, such as the above-mentioned, does not seem to have any mathematical structure conducive to computational implementations. Nevertheless, when f(x) is a continuous function and S is a nonempty closed set the problem can be transformed into an equivalent problem expressed by minimize l(z) subject to z 2 D n intC (canonical d.c. program), where l(z) is a convex function (which is usually a linear function) and D and C are closed convex sets. A mathematical complementary convex structure such as D n int C is not always apparent and even when it is explicit, a lot of work still remains to be done to bring it into a form amenable to efficient computational implementations. The attractive feature of the mathematicalcomplementary convex structure is that it involves convexity. Thus, we can use analytical tools from convex analysis like sub differential and supporting hyper plane.On the other hand, since convexity is involved in a reverse sense, these tools must be used in some specific way and combined with combinatorial tools like cutting planes, branch and bound and outer approximation.We introduce the common general mathematical complementary convex structure underlying in global optimization problems and describe the Generation Problem, whose functions are d.c. functions because they are polynomials. Thus, by using the properties of the d.c. functions, we describe the Generation Problem as an equivalent canonical d.c. programming problem. From the structure of its functions the Generation Problem can be rewritten as a more suitable equivalent reverse convex program in order to obtain an adaptation for advantageous numerical implementations.Concepts and properties are introduced which allow us to obtain an explicit representation of a polynomial as a deference of convex polynomials, based on the fact that the set of mth powers of homogeneous polynomials of degree 1 is a generating set for the vector space of homogeneous polynomials of degree m.We also describe a new global optimization algorithm (adapted algorithm) in order to solve the Generation Problem. Since the equivalent reverse convex program is unbounded we use prismatical subdivisions instead of conical ones. Moreover, we prove the convergence of the adapted algorithm by using a prismatical subdivision process together with an outer approximation procedure.We enounce the Minimal Norm Problem by using the concept of Least Deviation Decomposition in order to obtain the optimal d.c. representation of a polynomial function, which allows a more efficient implementation, by reducing the number of iterations of the adapted algorithm.A quadratic semi-infinite algorithm is described. We propose a build-up and down strategy, introduced by Den Hertog (1997) for standard linear programs that uses a logarithmic barrier method.Finally, computational results are given and conclusions are explained.

To increase real estate values, developers often apply designs on the land. In the case of a single family housing development, the designs are applied to the unit of subdivisions. In this study, the designs are defined as “value creation concepts,” which increase housing values at the subdivision level. The value creation concepts are classified into five categories – the sense of arrival, product mix, walkability, circulation system, and amenity. This cross-sectional study focuses on exploring the effects of value creation concepts in the subdivision. Two methodologies – the Hedonic Price Model (HPM) and the Hierarchical Linear Model (HLM) – are used to test whether or not the value creation concepts would increase or decrease single family housing values. The study sample is composed of 6,562 single family houses nested in 85 subdivisions in College Station, Texas. Data are composed of two levels: the housing level and the subdivision level. The scores of the sense of arrival were provided by sixtyone graduate students at Texas A&M University using photograph evaluations. Most structural variables were obtained from the Brazos County Appraisal District, and physical environmental variables were objectively measured using the Geographical Information System. In the both models, sense of arrival, greenway connectivity, sidewalk connectivity, and median length of cul-de-sac variables have positive effects on single family housing values while phased project, the number of accessible entrances, street density, single family density, and median length of block variables have negative effects on single family housing values. At the housing level, several structural variables (e.g. bathrooms, attached garage, porches, etc), attached to a golf course, sports facilities, network distance from the nearest elementary school, population density, and personal variables (i.e., tenure, workable age, employment) were significant (p<.05) predictors of single family housing value. Findings support that the value creation concepts have effects on increasing housing values at the subdivision level, which would provide thoughtful insights for developers in residential areas. In addition, the HLM can be used as the complement of the HPM by controlling interaction terms between housing variables and subdivision variables, or among the subdivision variables themselves.

The main objective with this study was to investigate so called odd purposes acceptable when registrating property along with how social development affects these purposes, furthermore to investigate how the cadastral surveyors estimates a foreseeable time. Tradition and praxis is used for several obvious purposes such as housing, farming, forests, offices and industry. Praxis is yet to be defined regarding more unique purposes. There is no mention in the law about which purposes are found acceptable to assure the demands on suitability are met. Cadastral authorities are responsible for making sure the division into property units is uniform and rule of law-accordingly. This study illustrates the issue of how the cadastral operation applies the rules to support a uniform application of the rule. A legal method, a survey analysis, an interview analysis and a case study were methods used in the study to answer the purpose and research questions. The legal method was used to learn more about the legal position. The survey was performed in order to gather data and information about which purposes previously have been regarded as odd by the cadastral surveyors. To obtain an understanding about and background to the selected odd purposes, an interview study was conducted with the cadastral surveyors. The intent of the case study was to form a base and insight in how the odd purposes are valued. The result of the legal method showed proof of how to interpret the prerequisite in the law. The survey provided information about which odd purposes are used in dividing of property. The interview study was based on the results from the survey and the information gathered from it. Answers regarding the background to the cadastral procedures were given, as well as the concept purpose, its origin and the evaluation of the time concept foreseeable time. The case study provided a background to the decision making and history about the debate as well as how purpose has been a question when making assessments. The most important conclusion made was that the prerequisite, intended function, current circumstances and requirements determine an acceptable purpose. The same factors determine the assessment of foreseeable time and as a result the concept varies from case to case. Social development causes the conditions for dividing into property units to be interchangeable, as a result the possible purposes changes with them. A more uniform application of the rule, considering the prerequisites, intended function, current circumstances and requirements should so be applied. / Huvudsyftet med studien var att undersöka vilka ”udda” ändamål som kan godtas vid fastighetsbildning med delsyften om hur samhällsutvecklingen påverkar ändamålen och att undersöka hur förrättningslantmätarna bedömer ”överskådlig tid”. Tradition och praxis finns för ett flertal ändamål som kan anses vara självklara, till exempel bostad, jordbruk, skog, kontor och industri. För mer udda ändamål är praxis oklar. Lagen talar inte om vilka ändamål som kan anses vara godtagbara för att kraven om lämplighet ska anses uppfyllda. Lantmäterimyndigheterna har till uppgift att ansvara för en enhetlig och rättssäker fastighetsindelning. Studien belyser frågan om hur lantmäteriverksamheten tillämpar reglerna idag för att ge stöd åt en enhetlig rättstillämpning. Metoder som använts i studien för att besvara syfte och forskningsfrågor var en juridisk metod, en enkätstudie, en intervjustudie och en rättsfallsstudie. Den juridiska metoden användes för att få kunskap om rättsläget. Enkätstudien genomfördes för att samla data och information om ändamål som förrättningslantmätarna ansett vara ”udda”. För att få förståelse och en bakgrund till förrättningarna av de utvalda ”udda” ändamålen genomfördes en intervjustudie med förrättningslantmätarna. Rättsfallsstudien syftade till att få en grund och inblick i hur ”udda” ändamål bedömts. Resultatet av den juridiska metoden visade på hur rekvisiten i lagen ska tolkas. Enkätstudien gav information för vilka ”udda” ändamål det fastighetsbildats. Intervjustudien grundade sig på enkätstudiens resultat och den information som lämnats. Den gav svar på förrättningarnas bakgrund, begreppet ändamålet och dess tillkomst och bedömningen av tidsbegreppet ”överskådlig tid”. Rättsfallsstudien gav en bakgrund till besluten och om hur diskussionerna förts samt huruvida ändamålet varit föremål för bedömning. Den viktigaste slutsatsen var att det är rekvisiten, den tilltänkta funktion, den rådande situation och behoven som avgör vilket ändamål som är godtagbart. Samma faktorer avgör bedömningen av överskådlig tid som i och med det varierar från fall till fall. Samhällsutvecklingen medför att förutsättningarna för fastighetsbildning är föränderliga och därmed förändras också möjliga ändamål. En enhetlig rättstillämpning bör därmed ske utifrån rekvisiten, den tilltänkta funktion, den rådande situation och behoven.