Ce travail est lié au système de protection des réseaux de distribution. Les réseaux radiaux dedistribution peuvent être protégés simplement par une protection placée en tête du départ. Maisl'exploitation future des réseaux de distribution, qui se transforment en réseaux intelligents,flexibles et adaptatifs, va sûrement nécessiter une protégeabilité plus complexe. Parconséquent, un nouveau plan de protection pourrait être nécessaire afin d’augmenter la fiabilitédu réseau de distribution et le taux de productions décentralisées. Il pourrait inclure plusieursprotections déployées sur un départ. Le but principal de ce travail est d'étudier comment lesprotections pourraient agir (sur quel genre de grandeurs les protections reposeront, quellecoordination faut-il choisir) et d'analyser les limites de ces nouvelles protections. En déployantplusieurs protections qui divisent le départ en des zones plus petites, le plan de protectionproposé, reposant sur une formulation modifié et optimisée, proche de celle des protections dedistance classiques, déconnectera ainsi moins de consommateurs et de producteurs lors del’apparition de défauts. Cela devrait réduire le temps de coupures brèves et de diminuerl'énergie non fournie. Ce manuscrit présente une solution pour les réseaux HTA radiaux faceaux défauts monophasés. / This work is related to the protection system of distribution networks. Radial MV distributiongrids can be protected by a single protection relay located at the beginning of the feeder. Butthe future operation mode of distribution grids turning into Smart Grids should impose morecomplex operations. Therefore a more advanced protection scheme could be needed, in orderto improve the reliability of the distribution network and to enhance the DG interconnection. Itcould include several protection relays in series on a same MV feeder. The main purpose of thiswork is to investigate how the protection relays could work (on which measurements should theprotection decisions be based, how to coordinate the relays without communication) andanalyze the limits of such new protection schemes. Since the goal is to insert severalprotections that divide the grid into smaller sections, the proposed protection system, based onan adapted and optimized formula, inspired by distance relays algorithm, would thereforedisconnect fewer loads and producers when faults occur in the MV network. This should reducethe clearing operation time and Energy Not Supplied criteria. This paper presents a solution fora radial MV grid facing single-phased faults.

Orientador: Christiano Lyra Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-06T02:47:37Z (GMT). No. of bitstreams: 1 Queiroz_LeonardoMendoncaOliveirade_M.pdf: 695151 bytes, checksum: 1dd5cfdea3e5f570eac87a0b801c8e25 (MD5) Previous issue date: 2005 / Resumo: Esse trabalho propõe um Algoritmo Genético Híbrido para o problema de redução de perdas em redes de distribuição de energia elétrica através de reconfigurações da rede, considerando-se as variações das demandas ao longo do dia. É adotada uma formulação que evita reconfigurações freqüentes, procurando encontrar uma única configuração para operação ao longo de todo o período em estudo, mas considerando explicitamente no processo de otimização a diversidade de variações de demanda ao longo da rede. A representação implementada garante a factibilidade dos indivíduos após a realização de cruzamento e mutação no processo de busca da melhor solução com o algoritmo genético. Foi incluída uma fase de busca local, o que caracteriza o método como um algoritmo genético híbrido. Com o objetivo de alternar entre estratégias de intensificação e diversificação, foram utilizadas técnicas de adaptação de parâmetros; mais especificamente, da probabilidade de mutação. Estudos com redes reais de médio e grande porte ilustram a aplicabilidade da metodologia proposta e sugerem alternativas para desdobramentos do trabalho / Abstract: This work proposes a Hybrid Genetic Algorithm approach to the problem of loss reduction in distribution systems by network reconfiguration strategies, under variable demands. A formulation that avoids frequent reconfigurations is adopted, searching for a fixed configuration to operate for the whole planning period, but taking into account demand variations on the optimization processo The chromosome representation adopted in the algorithm guarantees the factibility of the individuaIs after crossover and mutation operations on the process of searching for the best solution. A local search procedure is included, characterizing an hybrid implementation. Techniques of adaption of parameters were used (specifically mutation probability), to provide alternation between intensification and diversification strategies. Case studies with real distribution networks provide information on the possibilities of the approach and suggest alternatives to further investigations / Mestrado / Automação / Mestre em Engenharia Elétrica

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This Thesis deals with the power of a statistical test and the associated problem of determining the appropriate sample size. It should be large enough to meet the requirements of the probabilities of errors of both the first and second kind. The aim of this Thesis is to demonstrate theoretical methods that result in derivation of formulas for minimum sample size determination. For this Thesis, three important probability distributions have been chosen: Normal, Bernoulli, and Exponential.

En se basant principalement sur des études effectuées dans un contexte organisationnel, la littérature montre que l'intégration des canaux est la clef de réussite de toute expérience multicanal. Toutefois, très peu d'études se sont intéressées au point de vue du consommateur multicanal à ce sujet. Le consommateur multicanal est-il sensible aux efforts d'intégration des firmes multicanal ? Si oui, accorde-t-il la même importance à toutes les dimensions de l'intégration ? S'attend-t-il à une intégration parfaite des canaux de distribution d'une enseigne ? Pour répondre à ces questions, cette recherche propose un modèle intégrateur des principales dimensions de l'intégration perçue des canaux de distribution, élaboré sur la base d'une étude qualitative exploratoire. Son objectif consiste à déterminer l'impact de chacune d'entre elles sur l'évaluation globale de l'intégration, la confiance dans l'enseigne et les intentions de comportements multicanal. Nous avons choisi comme champ d'application pour le test de ce modèle, le cas des click and mortar de la filière de l'habillement et du prêt-à-porter. L'étude quantitative nous a permis de tester et de valider trois échelles de mesure élaborées dans le cadre de cette recherche. Il s'agit de l'échelle multidimensionnelle de l'intégration perçue des canaux, de l'échelle bidimensionnelle de l'évaluation globale de l'intégration et de l'échelle unidimensionnelle de l'intention d'achat cross-canal. Nous avons également adopté une approche comparative entre shoppers et clients multicanal. Elle nous a montré que les shoppers diffèrent des clients au niveau de certaines variables du modèle. De plus, les résultats empiriques nous ont permis de montrer l'impact des dimensions perçues de l'intégration dans la formation de l'évaluation globale de l'intégration, de la confiance dans l'enseigne et par conséquent des intentions de comportements multicanal. / Most based on an organizational context, previous studies show that channel integration is the key to succeed every multichannel experience. However, very few studies have focused on the consumer perspective. So does multichannel integration matter for the multichannel consumer? If so, does he find that all dimensions of integration are important? Does he expect a seamless integration of channels? To answer these questions, this research proposes an integrative model of the most important perceived integration dimensions of retailing channels. It has been developed on the basis of a literature review and a qualitative study. It aims to show the impact of each perceived integration dimension on the global evaluation of integration, trust and multichannel behaviors intentions. The quantitative study allowed us to test and validate three new-developed scales: perceived channel integration, global evaluation of integration and cross-channel purchasing intention. We have also compared multichannel shoppers and multichannel customers and showed that shoppers are different from customers. Moreover, the empirical results have shown and explained the impact of integration perceived dimensions on global evaluation of the integration, on trust and, therefore, on multichannel behaviours intentions.

We first consider confidence intervals for a normal percentile, an exponential percentile and a uniform percentile. Then we develop confidence intervals for a difference of percentiles from two independent normal populations, two independent exponential populations and two independent uniform populations. In our study, we mainly focus on the maximum likelihood to develop our confidence intervals. The efficiency of this method is examined via coverage rates obtained in a simulation study done with the statistical software R.

The dissertation considers construction of confidence intervals for a cumulative distribution function F(z) and its inverse at some fixed points z and u on the basis of an i.i.d. sample where the sample size is relatively small. The sample is modeled as having the flexible Generalized Gamma distribution with all three parameters being unknown. This approach can be viewed as an alternative to nonparametric techniques which do not specify distribution of X and lead to less efficient procedures. The confidence intervals are constructed by objective Bayesian methods and use the Jeffreys noninformative prior. Performance of the resulting confidence intervals is studied via Monte Carlo simulations and compared to the performance of nonparametric confidence intervals based on binomial proportion. In addition, techniques for change point detection are analyzed and further evaluated via Monte Carlo simulations. The effect of a change point on the interval estimators is studied both analytically and via Monte Carlo simulations.

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Typescript (photocopy). / Digitized by Kansas Correctional Industries

Typescript (photocopy). / Digitized by Kansas Correctional Industries