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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.
121

The perception of relevant surface cues shapes language development : evidence from typical and atypical populations / La perception des indices de surface influence le développement du langage : le cas des enfants typiques et atypiques

Marino, Caterina 27 November 2018 (has links)
L'objectif général de cette thèse est d'explorer comment les enfantes perçoivent des traits de surface du langage à différents niveaux. Plus spécifiquement, on a examiné dans une population typique et atypique 1) la perception des traits acoustiques de bas-niveau et sa relation avec le développement du vocabulaire, et 2) la sensibilité à la fréquence des mots pour générer la représentation linguistique abstraite des catégories lexicales et de leur ordre relatif. Selon les modèles de bootstrapping, il est possible d'extraire des informations structurelles et abstraites de la langue à partir de traits acoustiques disponibles dans l'input et corrélés avec la structure linguistique sous-jacente (p. ex. grammaire et syntaxe). Pour examiner le lien entre la perception de bas niveau, les traits de surfaces et les connaissances grammaticales plus abstraites, cette thèse s'articule en deux parties principales. Dans la première partie, deux études longitudinales sont présentées. Chaque enfant était testé sur son seuil de discrimination auditive (avec un paradigme de traitement rapide) et sur une tâche de reconnaissance visuelle pour contrôler les compétences cognitives. Le seuil acoustique était évalué en utilisant des sons non-linguistiques (tons) dans un groupe d'enfants et linguistiques (syllabes) dans un autre groupe d'enfants à 9 mois pour déterminer si l'impact du traitement auditif est spécifique au langage. Enfin, le niveau de vocabulaire a été mesuré à 12, 14, 18 et 24 mois et un test cognitif (Mullen Scale) a été réalisé entre 18 et 20 mois comme supplémentaire contrôle cognitif. Les résultats montrent que les capacités mesurées sont prédictives du développement du vocabulaire chez les enfantes typiques. De plus, les enfants atypiques ont montré des capacités de traitement moins efficaces dans les modalités visuelle et acoustique. Dans la deuxième partie, le rôle de la fréquence des mots dans l'amorçage des catégories lexicales des mots de fonction et de contenu et leur ordre relatif est explorée. Les deux catégories lexicales sont différentes dans leur fonction linguistique, leurs caractéristiques phonologiques et leur fréquence dans la parole. Ainsi, leur catégorisation basée sur la fréquence pourrait constituer un mécanisme initial robuste pour acquérir les constructions de base de la langue. Comme les mots de fonction constituent une classe fermée, alors que les mots de contenu constituent de classes ouvertes, nous avons examiné si les nourrissons français âgés de 8 mois étaient sensibles à la fréquence des mots pour catégoriser les mots de fonction et pour les traiter comme des éléments non-remplaçables dans des classes fermées, et les mots de contenu comme des éléments librement remplaçables dans des classes ouvertes. Les cinq expériences de grammaire artificielle menées ont confirmé cette hypothèse. De plus, les nourrissons associent l'ordre relatif de ces catégories avec l'ordre des mots de base de leur langue maternelle, le français. Les participants atypiques ont montré des capacités de discrimination, de codage et de mémoire inférieures à leurs pairs typiques. En conclusion, ce travail a permis une meilleure compréhension des capacités de perception contribuant au développement du langage. De plus, cette thèse a identifié de potentiels marqueurs comportementaux pouvant servir à l'identification précoce des apprenants atypiques. / The purpose of this work is to explore how infants perceive surface features of language at different levels of processing. Specifically, in both typical and atypical populations, we examined 1) the processing of low-level auditory cues and its relationship with later language outcomes and 2) the sensitivity to word frequency to create abstract linguistic representations of lexical categories and their relative word order. Accordingly to bootstrapping models learners are able to extract abstract, structural and hence directly unobservable properties of the target language from perceptually available surface cues in the input that correlate with the underlying structure. Indeed, infants are sensitive to certain acoustic and phonological properties of the speech input, which in turn correlate with specific grammatical/syntactic structures. In order to map the link between the perception of these low-level, surface cues and more abstract grammatical knowledge, this work is organized in two main parts. In the first part, two longitudinal studies are reported. Each infant received an auditory discrimination threshold task (using the rapid auditory processing paradigm) followed by a habituation/visual novelty detection task used as a control for general cognitive skills. The auditory discrimination threshold was evaluated using non-linguistic (tones) sounds in one cohort of infants and linguistic sounds (syllables) in another cohort of infants at 9 months in order to investigate the language-specificity of the process within the auditory modality. Subsequently, infants' vocabulary was assessed at 12-14-18 and 24 months and a cognitive test (Mullen scale) was performed at 18-20 months as another control measure for early processing competence. Results show that early processing abilities are predictive of later vocabulary size in typical infants. Importantly, atypical participants exhibited slower and less efficient processing abilities in both visual and acoustic modality. In the second part, the role of word frequency in bootstrapping the basic lexical categories of function and content words and their relative order is explored. The two lexical categories differ in their linguistic functions, phonological makeup and frequency of occurrence. Thus, their frequency-based discrimination could constitute a powerful initial mechanism for infants to acquire the basic building blocks of language. As functors constitute closed classes, while content words come in open classes, we examined whether 8 month-old French monolinguals relied on word frequency to categorize and track functors as non-replaceable items in a closed class, and content words as freely replaceable items in open classes. In five artificial grammar-learning experiments we have found that infants treat frequent words as belonging to closed classes, and infrequent words as belonging to open classes and they map the relative order of these categories onto the basic word order of their native language, French, a functor-initial language. Importantly, atypical participants showed lower ability of discrimination, encoding and memory when compared to typically developing peers. Overall this work contributes to a better understanding of the perceptual abilities that directly contribute to language development. Moreover, it proposes possible behavioural markers that can be potentially useful in the early identification of atypical learners.
122

Political Leadership Style in Kazakhstan

Tolymbek, Almaz Karim 30 July 2007 (has links)
No description available.
123

Les effets d’un traitement chronique aux antipsychotiques sur la poursuite d’une récompense conditionnée

Bédard, Anne-Marie 08 1900 (has links)
Les problèmes de toxicomanie sont très communs chez les schizophrènes. L’administration chronique d’antipsychotiques pourrait être impliquée dans cette cooccurrence en induisant une hypersensibilisation du système dopaminergique. Précédemment, nous avons démontré chez le rat qu’un traitement continu (via une mini-pompe osmotique sous-cutanée), et non pas intermittent (via des injections journalières sous-cutanées), avec l’halopéridol a augmenté la capacité de l’amphétamine à potentialiser un comportement de recherche de récompense. Dans cette étude, nous avons étudié les effets d’un antipsychotique atypique soit l’olanzapine comparé à l’halopéridol. Un traitement continu avec l’halopéridol, et non pas l’olanzapine, a augmenté la capacité de l’amphétamine de potentialiser la poursuite d’une récompense conditionnée (lumière/son préalablement associés à l’eau). De plus, un traitement continu avec l’halopéridol a augmenté l’induction par l’amphétamine de l’activité locomotrice et l’expression d’ARNm pour le c-fos (marqueur fonctionnel d’activité cellulaire) dans le caudé-putamen. Donc, un traitement continu avec un antipsychotique typique, et non pas atypique, a augmenté les caractéristiques motivationnelles attribuées à un stimulus neutre. Ceci est potentiellement lié à au développement d’un état de sensibilisation comportementale aux effets de l’amphétamine et à une augmentation de la capacité de l’amphétamine de susciter la modulation de l’activité du caudé-putamen. Ainsi, un antipsychotique typique tel que l’halopéridol semble modifier les circuits de la récompense de façon à contribuer à des comportements caractérisés par une recherche et une consommation de drogues d’abus alors qu’un antipsychotique atypique tel que l’olanzapine aurait moins tendance à le faire. Nous suggérons que les antipsychotiques atypiques pourraient être une meilleure option chez les patients schizophrènes à risque d’avoir un trouble de consommation de drogues d’abus ou de toxicomanie. / Substance abuse problems are excessively common in schizophrenia. Chronic antipsychotic treatment might be involved in this co-morbidity by inducing supersensitivity in the brain’s dopamine system. We have shown previously in the rat that continuous (via osmotic subcutaneous minipump), but not intermittent (via daily subcutaneous injection), treatment with haloperidol potentiates the ability of amphetamine to enhance the pursuit of a conditioned reward. Here, we assessed the effects of the atypical antipsychotic olanzapine. Continuous treatment with haloperidol, but not with olanzapine, enhanced the capacity of amphetamine to potentiate the pursuit of a conditioned reward (a light-tone stimulus previously paired with water). In addition, continuous haloperidol treatment augmented both amphetamine-induced locomotion and striatal c-fos mRNA expression. These effects were either absent or less pronounced following continuous olanzapine treatment. Thus, continuous treatment with a typical, but not with an atypical, antipsychotic enhanced the incentive motivational properties of a reward cue, and this was potentially linked to the development of behavioural supersensitivity to amphetamine and to a greater ability of amphetamine to engage the caudate-putamen. Thus, a typical antipsychotic like haloperidol appears to modify the brain’s reward system in ways that could contribute to drug-seeking and drug-taking behaviour, but an atypical antipsychotic like olanzapine might be less likely to do so. We suggest that atypical antipsychotics might be a preferential option in schizophrenic patients at risk for drug abuse or addiction.
124

L’influence de la vitesse d’administration de la cocaïne sur la consommation et motivation pour celle-ci, et l’influence d’un traitement antipsychotique sur la récompense conditionnée

Tzoneva, Mariana 12 1900 (has links)
Beaucoup de personnes consomment des drogues d’abus de façon récréative ou expérimentale dans leur vie, mais peu d’entre elles développent une toxicomanie. Nous avons exploré, chez le rat, deux facteurs impliqués dans la transition vers la toxicomanie, soit la vitesse à laquelle la drogue parvient au cerveau et le fait d’être sous traitement antipsychotique. Dans une première étude, notre objectif était de déterminer si augmenter la vitesse de livraison de la cocaïne (0.5 mg/kg) par auto-administration intraveineuse (i.v.; livrée en 5 secondes dans un groupe versus 90 secondes dans l’autre) mènerait à une plus grande consommation de celle-ci lors d’un accès prolongé (6 h/j versus 1 h/j), et à une plus grande motivation à obtenir la drogue telle que mesurée sous un ratio de renforcement progressif à une vitesse différente (10 secondes). Nous avons trouvé que le groupe 5 s consommait plus de cocaïne que le groupe 90 s en accès prolongé, mais aussi en accès limité. Cependant, la motivation des deux groupes était la même à la vitesse de 10 s, ainsi qu’à leurs vitesses initiales. Nous pensons que ceci peut être dû à une forme de plasticité du système méso-cortico-limbique survenue suite à l’auto-administration en accès prolongé en conjonction avec l’augmentation de consommation, chez les deux groupes, rendant impossible une distinction de leur motivation. Dans une deuxième série d’études nous avons émis l’hypothèse que l’antipsychotique typique, halopéridol (HAL, 0.5 mg/kg/j), et non l’atypique, aripiprazole (ARI, 1 mg/kg/j), un modulateur dopaminergique, induirait une augmentation de la poursuite de récompense conditionnée (RC) et de la locomotion (LOCO) en réponse à l’amphétamine (AMPH). Cependant, nous avons trouvé une augmentation chez le groupe HAL, mais non ARI, de la réponse RC, trois semaines, mais non une semaine post traitement, ainsi qu’une augmentation de la LOCO, chez le groupe HAL, mais non ARI, une semaine mais non trois semaines post traitement. L’incohérence des résultats entre les deux tests (RC et LOCO) rend leur interprétation difficile. Ces études restent à être explorées d’avantage afin de pouvoir en tirer des conclusions plus éclairées quant à l’impact de la vitesse d’administration de la cocaïne et du traitement antipsychotique sur le développement d’une toxicomanie. / Many people take drugs of abuse on a recreational or experimental basis in their lifetime, but few develop an addiction. We explored, in the rat, two factors involved in the transition to addiction: the speed at which the drug reaches the brain, and antipsychotic treatment. In the first study, our objective was to determine if increasing the speed of intra-venous (i.v.) delivery of cocaine (0.5 mg/kg) through i.v. self administration (delivered in 5 seconds in one group versus 90 seconds in the other) would lead to greater consumption with long access to the drug (6 hours/ day versus 1hr/day) and if the motivation to obtain the drug, as measured by a progressive ratio schedule would also be greater at a different speed (10 seconds). We have found that the 5 s group had a greater consumption than the 90 s group, in long access, but also in short access. However, the motivation of the two groups did not differ at the speed of 10 s, nor at their initial speeds. We suggest that this might be due to a form of plasticity of the mesocorticolimbic system, following the extended self-administration access, in both groups, in conjunction with the escalation in consumption, thus making it impossible to distinguish their motivation. In a second study series, we hypothesised that the typical antipsychotic, haloperidol (HAL, 0.5mg/kg/d), but not the atypical, aripiprazole (ARI, 1mg/kg/d), would increase the pursuit of conditioned reward (CR; here sound and tone) and locomotion (LOCO) in response to amphetamine (AMPH). We found an increase in the CR response, in the HAL group, but not the ARI group, three weeks, but not one week, post treatment, as well as an increase in the LOCO, in the HAL group, but not in the ARI group, one week but not three weeks post treatment. The incoherence of the results from the two tests (CR and LOCO) renders their interpretation difficult. These studies remain to be explored more thoroughly so as to obtain more enlightened conclusions as to the influence of speed of administration and antipsychotic treatment on addiction development.
125

Typical representations for GL_n(F) / Représentations typiques pour GL_n(F)

Nadimpalli, Santosh VRN 16 June 2015 (has links)
Dans cette thèse, nous classifions représentations typiques pour certaines composants Bernstein. Suite aux travaux de Henniart dans le cas de GL_2(F) et Paskunas pour les composants cuspidales, nous classifions représentations typiques pour les composants de niveau zéro pour GL_n(F) pour n> 2, composants de série principale, composants avec Levi sous-groupe de la forme (n, 1) pour n>1 et certains composants avec sous-groupe de Levi de la forme (2,2). Chacun des composants ci-dessus est traité dans un chapitre distinct. La classification utilise la théorie des types développés par Bushnell-Kutzko d'une manière significative. Nous allons donner la classification en termes de types de Bushnell-Kutzko. / In this thesis we classify typical representations for certain non-cuspidal Bernstein components. Following the work of Henniart in the case of GL_2(F) and Paskunas for the cuspidal components, we classify typical representations for of level-zero components for GL_n(F) for n>2, principal series components, components with Levi subgroup of the form (n, 1) for n>1 and certain components with Levi subgroup of the form (2,2). Each of the above component is treated in a separate chapter. The classification uses the theory of types developed by Bushnell-Kutzko in a significant way. We will give the classification in terms of Bushnell-Kutzko types for a given inertial class.
126

Limeira: produção social da cidade e do seu tecido urbano / Limeira: production of the city and its urban tissue

Queiroz, Alessandra Natali 14 June 2007 (has links)
A pesquisa tem a ênfase em levantar, inventariar e analisar as características tipológicas de tecido urbano e a configuração produtiva imobiliária que lhes deu origem, numa cidade de médio porte que participa de uma Região Administrativa como a de Campinas. É o estudo de uma cidade díspar das regiões metropolitanas de São Paulo ou mesmo a de Campinas, entretanto constitui-se na qualidade de um aglomerado urbano numa posição destacada entre suas cidades vizinhas. Ressalta-se na dissertação de mestrado o levantamento de cidades do interior paulista, com enfoque na estruturação urbana mediante a classificação de suas vias principais de expansão e a escolha de uma via para um estudo mais aproximado, baseando-se na metodologia morfotipológica do trabalho de Campos Filho. Uma metodologia de trabalho que ainda é mais bem tratada na cidade de São Paulo em prejuizo de cidades que vêm acolhendo fluxo considerável de migrantes, inclusive provenientes da capital O estudo atua na classificação de níveis diferenciados de centralidades de comércios e serviços e como esse tecido se comporta nessas variações, lembrando que o tecido engloba tanto a tipologia arquitetônica e suas instâncias de disposição no lote e volumetrias, quanto as tipologia das vias de circulação e capacidade de suporte nos espaços de passagem de veículos e pedestres. Assim, a análise do espaço urbano de Limeira ganha relevância ao se constituir como um dos exemplos de um processo de urbanização crescente que vem atingindo e transformando diversas cidades do interior. / This paper is concerned with the issue of surveying and analyzing the typological characteristics of the urban tissue resultant from the productive real estate configuration in a medium syze city- township which is under Campinas dependency. This case study examines Limeira municipality that obviously differs from the metropolitan areas of São Paulo or even from those of Campinas, but, at the same time belongs to the last. Nonetheless, it constitutes itself as an outstanding urban agglonerate among its neighborhood. Besides an overview of hinterland towns of São Paulo State, it´s inteded to highlight the urban structure by means of classifying Limeira´s dynamics of expansion by choosing one of the major streets and classifying its different levels of commercial and service centers and, moreover, how the urban tissue performs in this variation, realizing that the tissue includes not only the architectural typology and its disposition on the lot and volumetry but also the typology of streets with their use of the public space, including the vehicles circulation. The methodology applied is based upon Campos Filho´s morpho and typological analysis. This methodology has been more accepted in larger cities like São Paulo, neglectting smaller ones which also have a considerable migratory flow from all over the country and recently from São Paulo as well. Therefore, the analysis of the urban tissue of Limeira is important to the quality of life of its inhabitants, as an example of the increasing urbanization that has been occurring and transforming a great deal of hinterlands towns in São Paulo State.
127

Determinação de parâmetros do modelo pressão-vazamento para setor de distribuição de água da cidade de Piracicaba, SP / Determination of parameters of the pressure-leakage model for a water supply network of Piracicaba city, SP

Manzi, Daniel 30 April 2004 (has links)
A redução das perdas em sistemas de distribuição de água tem se tornado, além de uma questão ética, um determinante da eficiência e mesmo da sobrevivência das concessionárias destes serviços. A quantificação e determinação da natureza das vazões perdidas, que possuem relação íntima com as pressões de operação, são aspectos que ainda merecem análises mais profundas e práticas. Os parâmetros do modelo pressão-vazamento permitem o detalhamento das perdas físicas e foram obtidos por meio de calibrações para um setor de distribuição de água da cidade de Piracicaba, SP, em padrões hidráulicos distintos - sob hipótese de consumo noturno nulo (vazão mínima noturna), descargas de rede, patamares de pressão e sob consumo diurno dirigido pela pressão através de curvas encontradas na literatura e propostas. Os resultados obtidos indicaram que os valores dos parâmetros do modelo pressão-vazamento não são fixos, mas variam conforme o padrão hidráulico de operação da rede. Estudos acerca do parque de hidrômetros e seus desvios de indicação também foram realizados, em conjunto com uma análise das vazões típicas de abastecimento residencial, e apontaram para fortes erros de medição em razão do uso de reservatórios domiciliares. / Losses reduction on water supply networks came to be, beyond the ethical question, a condition for efficiency and even survival of enterprises which develop those services. Quantification and determination of the nature of leakage, which are closely related to operational pressure, are aspects which still claim for deeper and more practical analysis. Parameters to the pressure-leakage model allows to detail physical losses at one given system, and they were obtained throughout employment of distinct hydraulic patterns - minimal night flow (no usage), network flush situations, pressure levels and day usage driven by pressure from curves found on lectures and author\'s propositions - when proceeding calibration at a water supply section at the Piracicaba city, SP. Achieved results have shown that pressure-leakage model parameters values are not constant, but really change according to network\'s operational hydraulic pattern. Studies concerning section\'s water flow meters and its measuring deviation were also done, and joined to an analysis of typical patterns of home usage flows; they have pointed to huge metering errors because of employment of home reservoirs.
128

Critérios para avaliação da ilicitude na publicidade / Unlawfulness valuation criteria in advertising

Dias, Lucia Ancona Lopez de Magalhães 19 March 2010 (has links)
A temática da publicidade encontra-se normatizada no Código de Defesa do Consumidor a partir de princípios e cláusulas gerais, que, se virtuosas pela abrangência interpretativa, igualmente passíveis de desencadear grande insegurança jurídica quando não calcadas em consolidada doutrina e parâmetros interpretativos concretos. Nesse contexto, a presente tese tem por escopo conferir nova e detalhada sistematização ao tema e, fundamentalmente, fornecer ao operador do direito diretrizes palpáveis à análise da enganosidade e abusividade nas mensagens publicitárias. Trata-se, por exemplo, da necessidade de se analisar a (i)licitude da publicidade a partir da figura do consumidor como critério interpretativo central do artigo 37 CDC, procedendo-se a uma releitura do conceito de consumidor médio. No exame da publicidade enganosa, em especial no âmbito da sua tutela difusa, propõe-se, ademais, o critério de investigação do consumidor típico da publicidade, a partir do qual o potencial de indução em erro poderá ser melhor apreendido. A tese aborda ainda o conceito de dado essencial para configuração da enganosidade por omissão e ressalta os efeitos das mensagens secundárias ao slogan principal da publicidade. Tema igualmente novo refere-se à adoção das pesquisas de mercado na constatação da (i)licitude da publicidade. No que tange à publicidade abusiva, o trabalho se lança ao exame e delimitação de seus conceitos indeterminados, destaca o aspecto da tutela dos valores da coletividade e demonstra a impropriedade de uma análise puramente subjetiva e individual dessas peças publicitárias. O presente estudo apresenta ainda um quadro sistemático das técnicas publicitárias mais freqüentes, i.e., merchandising, publicidade redacional, teaser, exagero publicitário e mensagem de tom excludente, publicidade testemunhal e comparativa, analisando suas implicações no âmbito do direito do consumidor. Por fim, aborda-se a responsabilidade civil na publicidade ilícita e os pressupostos do dever de indenizar. Examina-se a reparação do dano moral (individual e coletivo) e o aspecto punitivo de tais indenizações, bem como os sujeitos da responsabilidade civil e a existência (ou não) de uma responsabilidade solidária entre anunciante, agência, veículo e celebridades. / Advertising is regulated by the Consumer Defense Code (CDC) according to principles and general rules that, notwithstanding being characterized by their constructive scope, may give rise to legal uncertainty whenever they are not grounded on settled legal doctrine and concrete constructive parameters. In this context, the present thesis aims to grant new and detailed systematization to the issue, and provide lawyers with tangible directions to analyze the deceptiveness and abusiveness within advertising messages. It regards, for instance, the need to analyze advertising (un)lawfulness from the consumers standpoint as the core constructive criterion of article 37 of the CDC. At this point we scrutinize in details the concept of reasonable consumer. Upon examining deceptive advertising, especially with regard to its diffuse protection, we propose, in addition, the typical consumer investigative criterion in advertising whereby potential error induction may be better understood. The thesis also addresses the essential data concept to configure deceitfulness by omission, and underscores the effects of secondary messages on the main advertising slogan. Likewise, the theme is related to the adoption of market research to ascertain advertising (un)lawfulness. Considering abusive advertising, this thesis examines its undetermined concepts, highlights the protection of collective values, and evidences the inadequacy of its subjective and individual analysis. The present study also offers a systematic table of the most frequent advertising techniques, i.e., merchandising, copywriting, teaser, exaggerated and excluding advertising, testimonial and comparative advertising, analyzing their entailments within Consumer Law. Finally, the work addresses the liability related to unlawful advertisement and the elements that determine the duty to indemnify. Pain and suffering redress (either individual or collective) and the punitive feature of such indemnification are examined herein, as well as the liable subjects and the existence (or not) or joint liability among the sponsor, advertising agency, media vehicle and celebrities.
129

Cálculo de perdas técnicas em sistemas de distribuição - modelos adequáveis às características do sistema e à disponibilidade de informações. / Technical losses estimation in distribution systems - adaptative models to the system characteristics and availability of information.

André Méffe 19 December 2006 (has links)
Este trabalho tem por objetivo apresentar e discutir alguns modelos para cálculo de perdas técnicas e não técnicas em sistemas de distribuição, considerando diversas alternativas em função da disponibilidade de dados. A discussão é de fundamental importância, na medida que o setor elétrico passa a enfrentar novos desafios, tais como o cálculo de redes de baixa tensão com cadastro incompleto e o cálculo de perdas não técnicas com sua respectiva parcela de perdas técnicas. Para o cálculo das perdas em redes de baixa tensão com cadastro incompleto, duas situações são consideradas. Na primeira, a rede é conhecida, porém não se conhece a localização de seus consumidores. Na segunda situação, também a rede é desconhecida. Neste último caso, para superar o problema de ausência de informações, são utilizadas técnicas de classificação para definir um conjunto de padrões de redes típicas e posterior associação de cada rede a um padrão previamente estabelecido. Também são utilizados alguns modelos de distribuição da carga e a consideração de incertezas é contemplada a partir de números difusos. Para calcular as perdas não técnicas com sua respectiva parcela de perdas técnicas, propõe-se um método para corrigir a energia faturada dos consumidores a partir do conhecimento da energia medida e das perdas técnicas calculadas. Uma extensão desse método ainda permite calcular as perdas de forma rápida e sem grandes esforços computacionais (método expedito), partindo do resultados de um cálculo realizado com um método convencional. Todos os modelos propostos são aplicados a redes de distribuição reais. Os resultados obtidos são analisados e comparados a valores de referência e é discutida a aplicabilidade dos modelos, bem como suas respectivas faixas de validade. / This work aims at presenting and discussing some models for calculating technical and non-technical losses in distribution systems. The proposed methods comprise several possibilities depending on the available data. This discussion is very important since the electric sector faces new challenges, such as technical loss estimation in low voltage networks with incomplete data. The evaluation of non-technical losses is also herein discussed. Regarding loss estimation with incomplete data, two conditions are considered. In the first one, the network data is known, but the customers location are unavailable. In the second one, the network data is not completely known as well. In this latter condition, in order to overcome the lack of sufficient data, classification techniques are used to establish a set of typical network patterns and to associate each network to a previously established pattern. Some load distribution models are also used and the uncertainties are considered by the use of fuzzy sets. In order to estimate the non-technical losses and their related technical losses, a method to adjust the billed energy in all customers is proposed. This is accomplished by using the computed technical losses and the measured energy at the substation site. This method also makes possible the assessment of technical losses in a quick way with a low computational effort (fast method). Such method is accomplished by using the results of a calculation previously performed using the conventional method. All the proposed methods are applied to real distribution networks. The obtained results are discussed and compared to the results obtained with the conventional method. The applicability of each model is also discussed.
130

Cálculo de perdas técnicas em sistemas de distribuição - modelos adequáveis às características do sistema e à disponibilidade de informações. / Technical losses estimation in distribution systems - adaptative models to the system characteristics and availability of information.

Méffe, André 19 December 2006 (has links)
Este trabalho tem por objetivo apresentar e discutir alguns modelos para cálculo de perdas técnicas e não técnicas em sistemas de distribuição, considerando diversas alternativas em função da disponibilidade de dados. A discussão é de fundamental importância, na medida que o setor elétrico passa a enfrentar novos desafios, tais como o cálculo de redes de baixa tensão com cadastro incompleto e o cálculo de perdas não técnicas com sua respectiva parcela de perdas técnicas. Para o cálculo das perdas em redes de baixa tensão com cadastro incompleto, duas situações são consideradas. Na primeira, a rede é conhecida, porém não se conhece a localização de seus consumidores. Na segunda situação, também a rede é desconhecida. Neste último caso, para superar o problema de ausência de informações, são utilizadas técnicas de classificação para definir um conjunto de padrões de redes típicas e posterior associação de cada rede a um padrão previamente estabelecido. Também são utilizados alguns modelos de distribuição da carga e a consideração de incertezas é contemplada a partir de números difusos. Para calcular as perdas não técnicas com sua respectiva parcela de perdas técnicas, propõe-se um método para corrigir a energia faturada dos consumidores a partir do conhecimento da energia medida e das perdas técnicas calculadas. Uma extensão desse método ainda permite calcular as perdas de forma rápida e sem grandes esforços computacionais (método expedito), partindo do resultados de um cálculo realizado com um método convencional. Todos os modelos propostos são aplicados a redes de distribuição reais. Os resultados obtidos são analisados e comparados a valores de referência e é discutida a aplicabilidade dos modelos, bem como suas respectivas faixas de validade. / This work aims at presenting and discussing some models for calculating technical and non-technical losses in distribution systems. The proposed methods comprise several possibilities depending on the available data. This discussion is very important since the electric sector faces new challenges, such as technical loss estimation in low voltage networks with incomplete data. The evaluation of non-technical losses is also herein discussed. Regarding loss estimation with incomplete data, two conditions are considered. In the first one, the network data is known, but the customers location are unavailable. In the second one, the network data is not completely known as well. In this latter condition, in order to overcome the lack of sufficient data, classification techniques are used to establish a set of typical network patterns and to associate each network to a previously established pattern. Some load distribution models are also used and the uncertainties are considered by the use of fuzzy sets. In order to estimate the non-technical losses and their related technical losses, a method to adjust the billed energy in all customers is proposed. This is accomplished by using the computed technical losses and the measured energy at the substation site. This method also makes possible the assessment of technical losses in a quick way with a low computational effort (fast method). Such method is accomplished by using the results of a calculation previously performed using the conventional method. All the proposed methods are applied to real distribution networks. The obtained results are discussed and compared to the results obtained with the conventional method. The applicability of each model is also discussed.

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