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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.
741

High Frequency Characterization and Modeling of SiGe Heterojunction Bipolar Transistors

Malm, B. Gunnar January 2002 (has links)
No description available.
742

Le droit au respect des modes de vie minoritaires et autochtones dans les contentieux internationaux des droits de l'homme

Farget, Doris 07 1900 (has links)
La présente recherche a pour objectif d’expliquer et d’évaluer le processus d’émergence du droit au respect des modes de vie minoritaires et autochtones, qui se manifeste devant deux juridictions et une quasi-juridiction : les cours européenne et interaméricaine des droits de l’homme et le Comité des droits de l’homme des Nations Unies, dont les jurisprudences feront l’objet d’une comparaison. Un tel sujet soulève plusieurs questions, dont celles de savoir à quel stade de ce processus nous en sommes, quel est le niveau de juridicité de la norme, mais aussi, quelle est la signification de ce droit, quels en sont les apports et comment se produit sa mise en œuvre. En proposer une interprétation éclairée suppose d’évaluer la référence au concept de mode de vie faite par les requérants, les juges et les experts. Cette démarche implique d’avoir recours à l’interdisciplinarité, plus précisément à certaines études anthropologiques. Cela requiert également un examen du discours des juges, des experts et des requérants pour en observer les convergences et les décalages. Quant aux résultats de recherche, le rôle de plusieurs acteurs au processus d’émergence de la norme nouvelle – les requérants, les juges ou les experts et les États – est souligné. Cela confirme la théorie de la polycentricité en matière de construction de certaines règles de droit international. La juridicité du droit au respect des modes de vie minoritaires et autochtones et sa force varient en fonction des systèmes, mais il possède toujours les caractéristiques propres à la norme juridique internationale. Cette dernière consacre un droit spécifique appartenant aux peuples autochtones et tribaux ou aux membres de peuples autochtones et minoritaires. Elle protège un rapport au territoire, soit un mode d’appréhension et d’exploitation, mais aussi de circulation et d’établissement sur celui-ci, ainsi que des activités. Les requérants roms, tribaux ou autochtones participent, bien qu’officieusement, à la définition juridique de leurs modes de vie, puisque les requêtes qu’ils déposent devant les juridictions supranationales constituent le fondement des interprétations judiciaires. Malgré ce processus de codétermination, certains décalages persistent entre les positions des divers acteurs impliqués dans la détermination du sens de la norme. Ils sont liés à l’impossibilité pour les juges d’appliquer au cas d’espèce une protection de leurs modes de vie, à l’éloignement entre la position des requérants et celle de l’État défendeur ou encore à la protection des droits des tiers. Une double surdétermination de la norme est donc constatée, par les conceptions des juges ou des experts, mais aussi par celles des requérants. Elle comporte certains risques d’essentialisation et d’idéalisation des modes de vie minoritaires et autochtones, de paternalisme, de victimisation ou de discrimination vis-à-vis des requérants ou de leurs communautés, sachant que ces risques sont tous à même de dénaturer le sens et la portée de la norme. Pour autant, cette dernière est porteuse d’avancées théoriques. Celles-ci ont trait à la coexistence, au sein de territoires identiques, entre groupes aux identités différentes, à l’amélioration de la qualité de vie des requérants et au processus de reconnaissance. La place occupée par la volonté des États, l’importance pour les juges de préserver leur légitimité, de même que le caractère idéaliste ou dogmatique de l’interprétation proposée, en limitent les apports théoriques. Il ressort de cette réflexion que la bonne articulation des divers discours en présence et l’émergence d’une norme efficace tiennent d’abord à l’énonciation et à la clarté des revendications des requérants minoritaires et autochtones. Elles tiennent ensuite à la réceptivité des agents qui les reçoivent – juges et experts – ainsi qu’au contexte politique, social et culturel qui les entourent. Cette analyse met ainsi en évidence l’importance d’exploiter la marge de manœuvre dont dispose chaque acteur du processus d’émergence dans la détermination du sens et de la portée des normes. / This research aims to explain and evaluate the emergence of a right of minorities and indigenous peoples to the respect of their ways of life, appearing before the European court of human rights, the Inter-American court of human rights and the United Nations Human rights Committee. The decisions and communications stemming from these tribunals will be analyzed and compared. This topic raises several questions regarding the legality of this norm, its meaning, effectiveness and limits, but also its implementation. In order to offer an interpretation of the content of that right, we need to evaluate the references made to it by the claimants, the judges and experts, which implicates an interdisciplinary approach focused on anthropological studies of law. This leads us to examine the discourses of judges, experts and claimants, to compare them and to observe their confluences and discrepancies. The results of this study show us that the emergence of this new norm is dependent upon the intervention of several agents – the claimants, the judges, the experts of the Committee and the States. This observation therefore confirms the polycentric process of construction of international legal rules. As to the legality and the effectiveness of the right of minorities and indigenous peoples to their ways of life, they vary according to the legal system, even if this right always corresponds to a legal rule. This rule consecrates a specific right belonging to indigenous and tribal people or to the members of indigenous people and minorities. It protects a relationship to the territory, i.e. a way to comprehend and to exploit it, to circulate on it and to inhabitate it. It also protects some activities. The indigenous, tribal and romas applicants unofficially take part in the legal definition of their ways of life, as the requests they submit to the international tribunals are cornerstones of judicial interpretations. In spite of a process of co-determination of the norm, gaps are observed between the positions of the different actors participating to the determination of the norm. They are either related to the impossibility for some judges to apply the right to a way of life to the case, to the distance between the positions of the claimants and the states, or to the protection of third parties. Consequently, a process of double distortion of the content of the norm appears, due to the judges’ or experts’ conceptions, but also to those of the claimants. It leads to the emergence of several problems, such as essentialism and the idealization of minorities and indigenous ways of life, paternalism, victimization or discrimination towards the claimants or their communities. These problems can alter the meaning and the impact of the norm. Nonetheless, the right to the respect of those ways of life has some theoretical effects related first to the coexistence, on a same piece of land, of different groups possessing diverse identities. They are also related to the improvement of the applicants’ quality of life and to the recognition process. However, the State’s willingness still occupies a large space in international law, as does the importance, for judges, to protect their own legitimacy. Moreover, some decisions seem too ideal or dogmatic. Those factors limit the effect of the norm. Thus, the articulation of judicial discourses and the efficiency of the norm are first contingent to the enunciation and to the clarity of the claimants’ requests. They are dependant of the receptivity of the agents whose role it is to receive them (judges and experts) and to the political, social and cultural context within which they take place. This last factor brings to light the importance for each agent participating to the elaboration of the norm to use, as much as he can, the margins he possesses. / Thèse de doctorat réalisée en cotutelle avec la Faculté de droit de l'Université Aix-Marseille 3.
743

"Analogue Network of Converters": a DfT Technique to Test a Complete Set of ADCs and DACs Embedded in a Complex SiP or SoC

Kerzerho, Vincent 22 February 2008 (has links) (PDF)
Une nouvelle méthode de test pour les convertisseurs ADC et DAC embarqués dans un système complexe a été développée en prenant en compte les nouvelles contraintes affectant le test. Ces contraintes, dues aux tendances de design de systèmes, sont un nombre réduit de point d'accès aux entrées/sorties des blocs analogiques du système et une augmentation galopante du nombre et des performances des convertisseurs intégrés. La méthode proposée consiste à connecter les convertisseurs DAC et ADC dans le domaine analogique pour n'avoir besoin que d'instruments de test numériques pour générer et capturer les signaux de test. Un algorithme de traitement du signal a été développé pour discriminer les erreurs des DACs et ADCs. Cet algorithme a été validé par simulation et par expérimentation sur des produits commercialisés par NXP. La dernière partie de la thèse a consisté à développer de nouvelles applications pour l'algorithme.
744

Operating voltage constraints and dynamic range in advanced silicon-germanium HBTs for high-frequency transceivers

Grens, Curtis Morrow 04 May 2009 (has links)
This work investigates the fundamental device limits related to operational voltage constraints and linearity in state-of-the-art silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) in order to support the design of robust next-generation high-frequency transceivers. This objective requires a broad understanding of how much "usable" voltage exists compared to conventionally defined breakdown voltage specifications, so the role of avalanche-induced current-crowding (or "pinch-in") effects on transistor performance and reliability are carefully studied. Also, the effects of intermodulation distortion are examined at the transistor-level for new and better understanding of the limits and trade-offs associated with achieving enhanced dynamic range and linearity performance on existing and future SiGe HBT technology platforms. Based on these investigations, circuits designed for superior dynamic range performance are presented.
745

Prospective control effect of exploratory-task-generated-motion on adaptation in real and virtual environments /

Littman, Eric Marshall. January 2009 (has links)
Thesis (M.A.)--Miami University, Dept. of Psychology, 2009. / Title from first page of PDF document. Includes bibliographical references (p. 43-47).
746

Old book, new lessons Mao, Osama, and the global Qutbist insurgency /

Rueschhoff, Jan L. January 2008 (has links)
Thesis (Master of Military Studies)-Marine Corps Command and Staff College, 2008. / Title from title page of PDF document (viewed on: Feb 11, 2010). Includes bibliographical references.
747

Retificador trifásico boost semi-controlado, com elevado fator de potência e controle por razão cíclica variável /

Morais, Douglas Carvalho January 2018 (has links)
Orientador: Falcondes José Mendes de Seixas / Resumo: Este trabalho tem como objetivo a proposição de um retificador trifásico boost semi-controlado, com correção ativa do fator de potência, que faça uso de técnicas de controle de razão cíclica variável, visando reduzir o conteúdo harmônico de corrente em baixa frequência. O conversor proposto opera em modo de condução descontínua, desta forma, a corrente de entrada segue uma envoltória senoidal. Além disso, devido ao modo de condução, o conversor apresenta a entrada em condução da chave com corrente nula, diminuindo assim, as perdas por chaveamento. Inicialmente, são apresentados, estudos teóricos da topologia em questão e, por meio de gráficos e equações, verifica-se a distorção harmônica imposta devida à operação com razão cíclica constante. Funções que permitam a variação permanente da razão cíclica, durante um ciclo da rede, serão apresentadas. Tais funções possuem o intuito de minimizar a distorção harmônica da corrente de entrada, com foco principal na 5ª componente harmônica. Resultados de simulação demonstram eficácia das técnicas de controle por razão cíclica variável e apontam redução no conteúdo harmônico de corrente. Resultados experimentais demonstram conteúdo harmônico de corrente em torno de 18% para operação do conversor com razão cíclica constante. A utilização de razão cíclica variável proporciona uma redução no conteúdo harmônico de corrente para 13%, resultando em um aumento do fator de potência. / Abstract: This work aims propose a three-phase rectifier boost half-controlled, with power factor correction, that makes use variable duty cycle control techniques, in order to reduce the harmonic content of current in low frequency. The proposed converter operates in a discontinuous current conduction mode, this way, the input current is naturally corrected. Moreover, due to the conduction mode, the converter presents entry in conduction of switch with null current, thus decreasing, the losses by switching. Initially, are presented theoretical studies of the topology in question and, through of graphs and equations, the harmonic distortion imposed by operation due constant duty cycle is verified. Functions that allow permanently the variation of duty cycle, during a network cycle, are presented. These functions have as main objective minimize the harmonic distortion in the input current, with focus in the 5th harmonic component. Simulation results demonstrate efficacy of techniques by variable duty cycle control and indicate a reducing of harmonic content of current. Experimental results demonstrate a reducing around 18% for operation with constant duty cycle. The use of variable duty cycle provides a reducing around 13%, resulting in an increase of the power factor. / Mestre
748

Estudo de técnica utilizando a modulação PWM baseada em portadora aplicada ao inversores monofásicos assimétricos com diodos de grampeamento

Oliveira, Francisco Hércules de 25 May 2017 (has links)
Submitted by Gilvanedja Silva (gilvanedja@biblioteca.ufpb.br) on 2018-03-22T20:42:08Z No. of bitstreams: 1 arquivototal.pdf: 11929036 bytes, checksum: e796f3e04cbf0cf6da3fa9648d4f9270 (MD5) / Made available in DSpace on 2018-03-22T20:42:09Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 11929036 bytes, checksum: e796f3e04cbf0cf6da3fa9648d4f9270 (MD5) Previous issue date: 2017-05-25 / This work presents a technique using carrier-based pulse width modulation (PWM) applied to single-phase asymmetrical multilevel inverters with diodes clamped, aiming to increase the amount of output voltage levels to improve signal quality, reducing the total harmonic distortion rate (THD). The technique was used in inverters of three, four and five levels per arm, providing an output signal with seven, thirteen and nineteen levels respectively, presenting two, six and ten levels higher than the equivalent symmetrical multilevel inverters. The technique was described with a set of equations and procedures that can be generalized for inverters of any number of levels. To verify the operation, simulations were performed using the PSIM program and an experimental assembly of an asymmetrical multilevel inverter of three levels was performed, using a field programmable gate array device (FPGA) in the implementation of the PWM modulator. Finally, the simulation and experimental results that prove the effectiveness of the modulation strategy employed in this work are presented and compared / Este trabalho apresenta uma técnica utilizando a modulação por largura de pulso (PWM) baseada em portadora, aplicada aos inversores multiníveis monofásicos assimétricos com diodos de grampeamento, com o objetivo de elevar a quantidade de níveis na tensão de saída, para melhorar a qualidade do sinal, reduzindo a taxa de distorção harmônica total (THD). A técnica foi empregada em inversores de três, quatro e cinco níveis por braço, fornecendo um sinal de saída com sete, treze e dezenove níveis respectivamente, apresentando dois, seis e dez níveis a mais que os inversores multiníveis simétricos equivalentes. A técnica foi descrita com um conjunto de equações e procedimentos que pode ser generalizada para inversores de qualquer número de níveis. Para comprovar o funcionamento, foram realizadas simulações utilizando o programa PSIM e efetuada montagem experimental de uma inversor multinível assimétrico de três níveis, utilizando na implementação do modulador PWM um dispositivo em matriz de porta programável em campo (FPGA). Por fim, são apresentados e comparados os resultados de simulações e experimentais que comprovam a eficácia da estratégia de modulação empregada neste trabalho
749

Mitigating the effect of soft-limiting for OFDM peak reduction

Bibi, Nargis January 2014 (has links)
Digital communication systems which use Orthogonal Frequency Division Multiplexing (OFDM) are now widely used and have many advantages. The main disadvantage is the requirement for highly linear analogue electronics including the high power amplifier (HPA). This requirement cannot be met in all circumstances because of the occurrence of symbols with high peak to average power ratio (PAPR). Such symbols may be non-linearly distorted by limiting. Approaches to solve this problem have been either to reduce the PAPR at the transmitter or to try to mitigate the effect of the non-linearity at the receiver. Soft-limiting, i.e. applying limiting in software prior to the HPA is a simple way to reduce the PAPR. It produces non-linear distortion which will cause an increase in the bit-error-rate (BER) at the receiver. This thesis surveys existing alternatives ways of reducing the effect of non-linearity and proposes some new ones. Two iterative receiver techniques, based on statistical analysis of the nature of the non-linearity, have been implemented and investigated. These are the ‘Bussgang Noise Cancellation’ (BNC) technique and the ‘Decision Aided Reconstruction’ (DAR) techniques. As these techniques are valid for any memory-less nonlinearity, an alternative form of limiting, named as Inverted-Wraparound (IWRAP) has been included in the BNC investigation. A new method is proposed which is capable of correcting the received time-domain samples that are clipped, once they have been identified. This is named the ‘Equation-Method’ and it works by identifying constellation symbols that are likely to be correct at the receiver. If there are a sufficient number of these and they are correctly identified, the FFT may be partitioned to produce a set of equations that may be solved for the clipped time-domain samples. The thesis proposes four enhancements to this new method which improve its effectiveness. It is shown that the best form of this method outperforms conventional techniques especially for severe clipping levels. The performance of these four enhancements is evaluated over channels with additive white Gaussian noise (AWGN) in addition to clipping distortion. A technique based on a ‘margin factor’ is designed to make these methods work more effectively in the presence of AWGN noise. A new combining algorithm referred as ‘HARQ for Clipping’ is presented where soft bit decisions are combined from multiple transmissions. ‘HARQ for Clipping’ has been combined with the best version of the Equation-Method, and the performance of this approach is evaluated in terms of the BER with different levels of AWGN. It has been compared to other approaches from the literature and was found to out-perform the BNC iterative receiver by 3dB at signal to noise ratios around 10dB. Without HARQ, the best version of the Equation-Method performs better than the BNC receiver, at signal-to-nose ratios above about 17dB.
750

[en] DREAM, NARRATIVE AND PSYCHOANALYSIS / [pt] SONHO, NARRATIVA E PSICANÁLISE

JULIA TEITELROIT DE SOUZA MARTINS 16 January 2019 (has links)
[pt] Sonho, Narrativa e Psicanálise é uma proposta de articulação entre os três eixos que dão nome à tese. O material apresentado é uma tentativa de explorar uma teoria a partir da combinação desses eixos e representa um esforço para trazer a psicanálise para o campo de estudos das narrativas ficcionais. Assim, os capítulos da tese dividem-se a partir das interseções entre os eixos: sonho e psicanálise; psicanálise e narrativa; narrativa e sonho. O que se propõe é uma investigação em torno do inconsciente, enquanto estruturado como uma linguagem, a partir do material dos sonhos e com a apuração de algumas poéticas literárias e cinematográficas de viés onírico, elegendo-se como pilares epistemológicos a psicanálise e sua influência nas teorias da arte a partir da década de 80, com destaque para os trabalhos de Paul Ricoeur, Peter Brooks e para a crítica de inspiração lacaniana, representada aqui por Jean-Pierre Oudart e Hal Foster. Em que medida tem valor a psicanálise para o campo de estudos narrativos? Onde buscar através dos sonhos e da psicanálise conhecimento sobre as narrativas? A distorção pareceu uma coisa a ser notada e compreendida. Cientes do mal de todo arquivo, ela foi eleita nossa chave de leitura, uma leitura que convoca o sujeito. Procurar o lugar do sujeito, da sutura, dos entretempos, aquele lugar onde o sujeito é convocado, talvez seja a forma privilegiada de trazer a psicanálise para o campo das artes, na medida em que se entenda que a arte implica em uma produção e em uma leitura (virtual) do arquivo (oculto) e que se leve em conta seu arquivamento diferenciado, deformado, distorcido. A primeira parte da tese serve para apresentar ao leitor os termos teóricos com que vamos trabalhar, dando-lhes um contexto, mas também procurando integrar os textos freudianos de uma maneira específica, dentro dos nossos propósitos. Na segunda parte, são abordadas algumas tentativas de aplicação da psicanálise no campo das artes, sendo três os caminhos que se destacaram no âmbito dessa pesquisa. Primeiro, o da crítica que procede analogicamente ao modelo dos sonhos, apresentada por Paul Ricoeur, que identificou o onírico em geral ao enxergar nos sonhos um valor de modelo. Um segundo caminho possível foi delineado por Peter Brooks, que propõe pensar um modelo econômico de narrativa enquanto estrutura espaço-temporal a partir do modelo econômico freudiano. A terceira via de aproximação entre a psicanálise e as artes tem inspiração lacaniana, trazendo para o centro da questão o lugar do sujeito em um modelo topológico. Por fim, a partir desses três caminhos de aplicação da psicanálise ao campo das artes em geral, e da arte narrativa em particular, será formada a base teórica para a análise crítica de um autor, o polonês Bruno Schulz, e de um roteiro cinematográfico original, que surgiu a partir de uma imagem de sonho. / [en] Dream, Narrative and Psychoanalysis is a proposal to articulate the three axes that name this dissertation. The material presented here is an attempt to explore a theory drawing on the combination of those axes, and it represents an effort to bring psychoanalysis to the field of fictional narrative studies. Thus, the chapters of the dissertation are divided based on the intersections between the axes: dream and psychoanalysis; psychoanalysis and narrative; narrative and dream. What is proposed here is an investigation around the language of the unconscious, drawing on the material of dreams, and examining some literary and cinematographic poetics with oneiric features. Psychoanalysis and its influence on theories of art after the 1980 s were elected as the epistemological pillars, highlighting the works of Paul Ricoeur and Peter Brooks and Lacan-inspired critique, here represented by Jean-Pierre Oudart and Hal Foster. To what extent is psychoanalysis valuable for the field of narrative studies? Where to seek knowledge about narratives through dreams and psychoanalysis? Distortion seemed like something to be noted and comprehended. With awareness of the archive fever, it was selected as the key to our reading, a reading that summons the subject. Searching for the place of the subject, of the suture, of the in-between, that place where the subject is summoned, may be the privileged way to bring psychoanalysis to the field of arts, insofar as it is understood that art entails a (virtual) production and a (virtual) reading of the (hidden) archive, and it is taken into account its differentiated, deformed, distorted archiving. The first part of the dissertation serves to present the theoretical terms that are going to be addressed, giving them a context, but also seeking to integrate the Freudian texts in a specific way, within our purposes. In the second part, some attempts of applying psychoanalysis to the field of arts are approached, and three paths stood out within the scope of this research. First, that of the critique that proceeds analogically to the dream model, presented by Paul Ricoeur, who identified the oneiric in general by seeing in dreams the value of a model. A second possible path was outlined by Peter Brooks, who proposes thinking of an economic model of narrative as a spatial-temporal structure based on Freud s economic model. The third path to bring psychoanalysis and art together is inspired by Lacan, foregrounding the issue of the subject s place in a topological framework. Finally, drawing on those three paths of psychoanalysis applied to the field of the arts in general, and of the narrative art in particular, the theoretical basis will have been laid for the critical analysis of an author from Poland, Bruno Schulz, and of an original screenplay, that unfolded from an image in a dream.

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