Orientador: José Roberto Sanches Mantovani / Resumo: Neste trabalho apresenta-se uma metodologia para a localização de faltas em alimentadores de distribuição de energia elétrica através do uso de técnicas de análise de redes baseadas na matriz de impedância e circuitos elétricos. A partir de medidas de tensão e corrente na saída do alimentador e medidas de tensão esparsas no alimentador o algoritmo é capaz de identificar e localizar faltas em alimentadores trifásicos radiais ou fracamente malhados, com cargas desequilibradas, ramais laterais trifásicos, bifásicos ou monofásicos e que tenham geração distribuída representada como uma barra de tensão controlada e que possua medidores de tensão. O sistema de diagnóstico e localização de faltas proposto é capaz de auxiliar as concessionárias de energia em sua rotina de trabalho, fornecendo informações importantes para a operação e manutenção dos sistemas elétricos de distribuição de energia, minimizando os tempos de reparos e, consequentemente, obtendo-se menos perdas financeiras devido ao rápido diagnóstico de faltas e restabelecimento das condições normais de operação. Um sistema de distribuição trifásico real de 135 barras, tensão nominal de 13,8 kV e potência nominal de 7,065 MVA foi utilizado para testar o algoritmo proposto, que apresenta resultados satisfatórios, mostrando-se ser um algoritmo eficiente e rápido. / Mestre

Cette thèse présente des contributions à la modélisation multivariée des queues de distribution. Nous introduisons une nouvelle modélisation des probabilités de queue jointes d'une distribution multivariée avec des marges Pareto. Ce modèle est inspiré de celui de Wadsworth et Tawn (2013). Une nouvelle variation régulière multivariée non-standard de coefficient une fonction à deux variables est introduite, permettant de généraliser deux approches de modélisation respectivement proposées par Ramos et Ledford (2009)et Wadsworth et Tawn (2013). En nous appuyant sur cette modélisation nous proposons une nouvelle classe de modèles semi-paramétriques pour l'extrapolation multivariée selon des trajectoires couvrant tout le premier quadrant positif. Nous considérons aussi des modèles paramétriques construits grâce à une mesure non-négative satisfaisant une contrainte qui généralise celle de Ramos et Ledford (2009). Ces nouveaux modèles sont flexibles et conviennent tant pour les situations de dépendance que d'indépendance asymptotique. / This PhD thesis presents contributions to the modelling of multivariate extremevalues. We introduce a new tail model for multivariate distribution with Pareto margins. This model is inspired from the Wadsworth and Tawn (2013) one. A new non-standard multivariate regular variation with index equals to a function of two variables is thus introduced to generalize both modeling approaches proposedby Ramos and Ledford (2009) and Wadsworth and Tawn (2013), respectively. Building on this new approach we propose a new class of non-parametric models allowing multivariate extrapolation along trajectories covering the entire first positive quadrant. Similarly we consider parametric models built with a non-negative measure satisfying a constraint that generalizes the Ramos and Ledford (2009) one. These new models are flexible and valid in both situations of dependence or asymptotic independence.

Aromatase is an enzyme that converts androgens to estrogens. In teleosts, brain aromatase, also known as aromatase B (cy19a1b), is only expressed in radial glial cells (RGCs). This is in contrast to aromatase A, which is expressed in gonads. Estrogens such as estradiol (E2) modulate neurogenesis in the adult teleost brain. Recent studies show that E2 also differentially regulates aromatase B expression in goldfish RGCs. As a result, teleost RGCs are suggested to be involved in regulating neurogenesis. In addition, aromatase B expression in goldfish RGC is under the control of dopamine suggesting that neurons and neurotransmitters can regulate RGC function. Interestingly, goldfish RGC transcriptome data shows the expression of one group of metabotropic glutamate receptors (mGluRs), group III mGluRs, which suggests that glutamate may affect RGC function. In this thesis, I present my findings regarding potential glutamatergic regulation of RGCs. Firstly, I investigated the distribution of glutamatergic synaptic vesicles and RGCs in the female goldfish forebrain. Double-staining immunohistochemistry shows that vesicular glutamate transporter (vGLUT) 1/2-labelled glutamatergic synaptic vesicles are in close anatomical proximity to aromatase B-labelled RGCs, which suggests potential regulation of RGCs by glutamate. Glutamatergic regulation of cyp19a1b, cyclin D1 (ccnd1), cyclin A2 (ccna2), mGluR6b (grm6b), mGluR7 (grm7), and mGluR8b (grm8b) expression in cultured adult female goldfish RGCs was also examined. Results from pharmacological manipulations and qPCR data analysis show that selective activation of group III mGluRs decreased cyp19a1b, ccnd1, and ccna2 mRNA via inhibition of cAMP/PKA signalling. Furthermore, grm7 mRNA is positively regulated by cAMP-dependent signalling. The glutamate analog L-glutamic acid decreased cyp19a1b mRNA and increased ccnd1 and grm6b mRNA in a dose-dependent manner. This suggests that ccnd1 and grm6b expression may be regulated by glutamate receptors other than group III mGluRs, for example, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, which are expressed in cultured goldfish RGCs. It was found that E2 upregulated cyp19a1b, ccnd1 and grm7 mRNA. However, selective activation of group III mGluRs decreases the stimulatory effect of E2 on ccnd1 expression. My findings show that glutamate finely regulates RGC neurogenic and steroidogenic genes, which may implicate glutamate in the regulation of RGC differentiation, RGC proliferation, and neurogenesis in surrounding cells.

abstract: In this work, I worked on the synthesis and characterization of nanowires and belts, grown using different materials, in Chemical Vapor Deposition (CVD) system with catalytic growth method. Through this thesis, I utilized the Photoluminescence (PL), Secondary Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray diffraction (XRD) analyses to find out the properties of Erbium Chloride Silicate (ECS) and two segment CdS-CdSe samples. In the first part of my research, growth of very new material, Erbium Chloride Silicate (ECS), in form of core/shell Si/ECS and pure ECS nanowires, was demonstrated. This new material has very fascinating properties for new Si based photonic devices. The Erbium density in those nanowires is which is very high value compared to the other Erbium doped materials. It was shown that the luminescence peaks of ECS nanowires are very sharp and stronger than their counterparts. Furthermore, both PL and XRD peaks get sharper and stronger as growth temperature increases and this shows that crystalline quality of ECS nanowires gets better with higher temperature. In the second part, I did a very detail research for growing two segment axial nanowires or radial belts and report that the structure type mostly depends on the growth temperature. Since our final step is to create white light LEDs using single axial nanowires which have three different regions grown with distinct materials and give red, green and blue colors simultaneously, we worked on growing CdS-CdSe nanowires or belts for the first step of our aim. Those products were successfully grown and they gave two luminescence peaks with maximum 160 nm wavelength separation depending on the growth conditions. It was observed that products become more likely belt once the substrate temperature increases. Also, dominance between VLS and VS is very critical to determine the shape of the products and the substitution of CdS by CdSe is very effective; hence, CdSe growth time should be chosen accordingly. However, it was shown two segmented products can be synthesized by picking the right conditions and with very careful analyses. We also demonstrated that simultaneous two colors lasing from a single segmented belt structures is possible with strong enough-pumping-power. / Dissertation/Thesis / M.S. Electrical Engineering 2012

During the project a test rig was constructed in which experiments were performed on radial bearings to evaluate the acoustic emission amplitude and RMS value of the signal. The acoustic emission amplitude depends on the Hertz contact time, i.e. the time it takes for the Hertz contact to roll over its own contact length. When the load remains constant on the bearing the Hertz contact time is directly reliant on the rotational speed of the inner ring of the bearing. Two experiments were performed, one on a spherical roller bearing and another identical experiment on a spherical ball bearing. Throughout both experiments the load on the bearing remained constant and the rotational speed of the inner ring was changed, the response of the speed change was measured using an acoustic emission sensor. The experiments found a quadratic dependency between the amplitude of the acoustic emission signal and the rotational speed of the inner ring. During the experiments the bearings were lubricated using grease and a total of 195 measurements were performed on each type of bearing at 13 different rotational speeds ranging between 1 and 3000 RPM.

Continuous design and improvements in performance of roller bearings have resulted in an increased power transmission whilst size and spatial requirements have been reduced. Radial cylindrical roller bearings have followed this trend and due to their high performance characteristics (such as high loading capacity and high rotational speed capabilities), they have obtained a firm place as high performance machine elements. An essential characteristic of a radial cylindrical roller bearing is the minimisation of frictional torque for particular operating conditions. In spite of these improvements in design and operation the bearing frictional torque is still usually calculated according to the Palmgren method first published in 1957. However, as a result of the increased performance of radial cylindrical roller bearings and a corresponding wider range of application this Palmgren method is insufficiently accurate for the prediction of frictional torques in modern bearings. Whilst the literature review in this thesis identified a variety of bearing frictional torque calculation methods, most of these methods are based on various ball bearing designs and are not necessarily applicable to cylindrical roller bearings types. As a result an accurate frictional torque prediction method is required for radial cylindrical roller bearings because of customer's demands. Consequently, the current project is combined with the development of a method of frictional torque prediction (FTP - Method), which enables the frictional torque of purely radially and radially and axially loaded radial cylindrical roller bearings to be calculated accurately. The FTP - Method is based on the physical effects producing the frictional torque in a bearing, such as the EHL - theory and a contact analysis to determine raceway rolling resistance, and in addition takes into account the frictional forces of the rib / rolling element end face rolling and sliding contact. Comprehensive experimental tests have been undertaken on different radial cylindrical roller bearing designs (including cage guided and full complement types) for a minimum of three different sizes to validate the derived equations. Good agreement was obtained between the predictions according to the FTP - Method and the measured test data for the frictional torqye of both radially and combined loaded bearings. Moreover, the thermal reference speed and the thermal limiting speed of a radial cylindrical roller bearing can be readily calculated for any operating condition using an explicit equation in the radial part of the FTP - Method. The thesis also presents a calculation program to illustrate a method of bearing design based on the thermal balance within a bearing. The bearing is initially pre-selected according to its life time requirements using a life time calculation. After the lubrication method has been defined a thermal balance can be used to design the bearing.

Introdução: A tuberculose e a histoplasmose são clínica-radiológica e histopatologicamente semelhantes, o que pode levar ao tratamento equivocado. Neste sentido, a importância do atual projeto é a confirmação de casos de histoplasmose em pacientes com suposta tuberculose, no Vale d Sinos – Rio Grande do Sul. Objetivo: Demonstrar a prevalência de histoplasmose a partir da detecção de anticorpos anti- Histoplasma capsulatum (H. capsulatum) em pacientes que possuíam diagnóstico inconclusivo e que receberam tratamento para tuberculose. Métodos e resultados: A primeira fase do estudo foi retrospectiva, com análise de prontuários para a seleção de pacientes cadastrados no Sistema Único de Saúde que receberam tratamento tuberculostático sem diagnóstico etiológico conclusivo para tuberculose. A segunda fase do estudo foi prospectiva, onde o soro dos pacientes que se enquadraram nos critérios de inclusão/exclusão foi analisado por imunodifusão radial dupla para a detecção da presença de anticorpos anti-H. capsulatum. Dos 42 soros testados, três (7,14%) tiveram resultado positivo para a presença de anticorpos anti-H. capsulatum. Conclusão: A ausência de achados etiológicos conclusivos para a tuberculose aliados à positivação da imunodifusão para H. capsulatum, demonstra que três pacientes apresentavam histoplasmose e não tuberculose, sugerindo a necessidade de pesquisa da micose nos casos com suspeita de tuberculose, mas sem confirmação diagnóstica. / Introduction: Tuberculosis and histoplasmosis are clinic-radiologic and hitopatologically similar, and so the treatment may be mistaken. In this sense, the importance of this project is to confirm histoplasmosis cases on patients who are being treated for supposed tuberculosis, in Vale do Sinos – Rio Grande do Sul. Aim: To demonstrate the prevalence of histoplasmosis by the presence of anti-Histoplasma capsulatum (H. capsulatum) antibodies in patients whose diagnosis is inconclusive and who have been treated for tuberculosis. Methods and Results: The first stage of the study was retrospective, by the analysis of medical records to select patients who are filed on Sistema Único de Saúde and who have received tuberculostatic treatment without conclusive etiologic diagnosis for tuberculosis. The second stage of the study was prospective, and the serum of patients who are integrated to inclusion/exclusion criteria was examined by double radial im munodiffusion to detect the presence of anti-H. capsulatum antibodies. From the 42 serum which were tested, three of them (7,14%) have had positive results for the presence of anti-H. capsulatum antibodies. Conclusion: The lack of conclusive etiologic find for tuberculosis associated to the positivation of immunodiffusion for H. capsulatum, proves that three patients have showed histoplasmosis and not tuberculosis, proposing then the necessity of a research of mycosis on the cases which there is the suspect of tuberculosis, but without diagnostic confirmation.

O torneamento radial é um processo de usinagem usado na indústria metal mecânica para o corte de peças, abertura de canais ou faceamento. Esta pode ser considerada uma operação crítica devido à forma geométrica da ferramenta e aos movimentos de corte. Isto gera a necessidade de aplicação de fluidos de corte, normalmente em abundância, na região de corte. Considerando como funções destes fluidos o arrefecimento, a lubrificação e a expulsão do cavaco, sua aplicação durante essa operação é de suma importância. Várias pesquisas visam restringir o uso de tais fluidos, seja por critérios econômicos, ambientais ou sanitários. Neste contexto, o uso da técnica de mínima quantidade de lubrificante (MQL) vem ganhando espaço nos meios produtivos. Embora seja aplicada há anos em diferentes processos de usinagem, existem poucos relatos sobre a aplicação de MQL em operações de torneamento radial; no mesmo seguimento, a aplicação de ar comprimido (ACO) vai ao encontro do conceito de usinagem ambientalmente amigável. Assim, este trabalho apresenta uma análise comparativa na aplicação de lubrificantes em abundância (ABD), em MQL e o uso de ACO no torneamento radial do aço SAE 1045 para diferentes condições de corte. Na investigação, foram consideradas as forças geradas durante o processo, as rugosidades e o desvio dimensional das superfícies usinadas, e o desgaste da ferramenta. Observou-se que os esforços gerados com MQL foram similares ou inferiores aos gerados com ABD. A mesma tendência foi observada no perfil de rugosidade, predominando valores inferiores. O MQL possibilita um corte mais estável durante a vida da ferramenta, reduzindo a ocorrência de desgaste e prolongando sua vida útil, minimiza a oscilação axial e a flexão da ferramenta, reduz as rugosidades e minimiza os desvios dimensionais. Assim, pode-se afirmar que a aplicação da técnica por MQL é viável no torneamento radial do aço SAE 1045. / Radial turning is a machining process used in the metalworking industry for parting off, grooving or facing operations. This can be considered a critical operation due to the geometric shape of the tool and the cutting movements. This generates the need for application of cutting fluids, usually in abundance, in the cutting region. Considering as functions of these fluids the cooling, lubrication and expulsion of the chip, their application during this operation is of paramount importance. Several researches aim to restrict the use of such fluids, either by economic, environmental or sanitary criteria. In this context, the use of the minimum quantity of lubricant (MQL) technique has been gaining ground in the productive media. Although it has been applied for years in different machining processes, there are few reports on the application of MQL in radial turning operations; at the same time, the application of compressed air (ACO) meets the concept of environmentally friendly machining. Thus, this work presents a comparative analysis on the application of abundant lubricants (ABD) in MQL and the use of ACO in radial turning of SAE 1045 steel for different cutting conditions. In the investigation, the forces generated during the process, the roughness and the dimensional deviation of the machined surfaces and the tool wear were considered. It was observed that the machining forces generated with MQL were similar or inferior to those generated with ABD. The same tendency was observed in the profile of roughness, predominating lower values. MQL enables a more stable cut during tool life, reducing the occurrence of wear and extending tool life, minimizes axial oscillation and tool flexion, reduces roughness and minimizes dimensional deviations. Thus, it can be indicated that the application of the technique by MQL is feasible in the radial turning of SAE 1045 steel.

The major objective of this thesis is to systematically investigate the effect of hexagonal BN (h-BN) islands on electronic and vibrational properties of single wall carbon Nanotubes. All our investigation are based on first principle Density Functional Theory (DFT) calculations. Our study is motivated by interesting metal-semiconductor transition recently found in periodically patterned graphene with h-BN islands. After reproducing the electronic band structure for pristine single wall zigzag carbon nanotubes (which shows metallic or semiconducting properties depending on their chirality), we investigated their electronic band structure in the presence of h-BN islands. The band structure depends not only on the defect concentration, but also on the pattern of the defect atoms. Our results also suggest that, if we start with a metallic /semiconducting mixture of ZSWCNTs, upon h-BN addition, the sample converts to fully semiconducting. This is a promising result for applications of CNTs in molecular electronics. Fundamental understanding of vibrational properties of nano electronics component is equally important in their applications especially in thermal management and thermoelectric applications. Defect engineering is one of the potential approach for tuning nanoelectronic devices for optimal thermal management and thermoelectric devices. In this work, I present a systematic investigation on how the group velocity and frequency of different phonon modes depend on various h-BN defect concentrations and defect patterns in ZSWCNTs. The study was extended to investigate the effect of hexagonal-C defects on the electronic and vibrational properties of zigzag single wall Boron Nitride nanotubes (ZSWBNNTs).

[pt] Neste trabalho, apresenta-se uma nova proposta para forma de bocais radicais de vasos esféricos tal que as tensões de flexão devidas a um carregamento axial sejam as mínimas possíveis. Investigam-se os esforços de flexão oriundos da compatibilização entre o bocal e o vaso utilizando a técnina dos elementos finitos com um elemento curvílineo com três nós e um campo de deslocamentos com quatro variáveis. Obtem-se, também, a distribuição de tensões proveniente da pressão interna para o bocal ótimo para esforço axial. Considera-se a união tubulação-vaso esférico com espessuras diferentes utilizando um local com a mesma forma de meridiano dos bocais ótimos, tendo, porém, espessura de parede variável. Tendo como objetivo a comparação com os bocais ótimos, anali sam-se, também, os bocais tradicionais. A nova geometria mostrou-se, para os casos usuais de carga, superior á convecional, no que se refere aos níveis de tensão alcançados. / [en] A new shape of radial nozzles for spherical shells is presented in this paper. The geometry is obtained imposing a bending-free condition for the transition between a cylinder and sheperical shell. The soltion is exact for ideal boundary conditions, and under the action of axisymetric axial load. In order to examine the load effects introduced by the spherical an cylindrical shells at the ends of the nozzle, it was performed a stress analysis of the whole structure, using the finite element technique with a curvilinear element. Two load cases were considered: axial load and internal pressure, for constant thickness nozzles and nozzles with variable thickness, the results were compared with the stress distribuition for a conventional nozzle under the same loading conditions. The new geometry proved to be superior as compared with the conventional one as far a stress instensities are taken into account, for the usual loading conditions.