京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20897号 / 理博第4349号 / 新制||理||1624(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 川畑 貴裕, 教授 永江 知文, 教授 鶴 剛 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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Sound transmission loss of vehicle seals was studied in this thesis. Reverberation room test and semi-anechoic chamber test were respectively studied. By comparing the sound pressure level, sound intensity level and average sound power level at the receiving side, it proved that a simple sound pressure level test may obtain same measurement accuracy when there is little reflected sound. A semi-anechoic chamber was designed for testing sound transmission losses of the seals on a trial vehicle. By comparing the sound pressure levels between the location of the passenger ear and door area, it proved that most of outside sound energy passed through the door seals into the interior. The sound transmission losses of different sealing conditions were measured which included well sealed and imperfectly sealed conditions; Sound pressure levels at passenger’s ear in three different types of vehicles were also compared, these comparison results indicated this laboratory was capable of distinguishing different sealing conditions. The installation procedure was compared with the one in reverberation room test. Numerical analysis showed that the latter method produced a different compression shape which would definitely influence the sound insulation abilities of the seals.   The transmission mechanism of the acoustic waves through a vehicle seal was also discussed. Contact analysis showed high compression ratio leaded to tremendous inner stress intensity. But any further increase of the contact depth would not improve the effect of wind noise prevention. A vehicle seal with a complex shape was replaced by a simple model. The sound transmission theory of multiple partitions on the basis of mass law was applied. Whereas, compared with the experimental result, a different trend in the high frequency range was found. When taking the transmission though the side material and integration of incident angle into account, the result was quite similar to the experimental one. FEM analysis was also performed. The majority of sound power was believed to transmit along the seal wall into the interior instead of passing through the multiple partitions. A distorted circular duct model is believed to be close to the real geometry. / QC 20101117

Cette thèse porte sur les artistes suédois et norvégiens en France de 1889 à 1908. Ces années ont traditionnellement été considérées comme une période de retour au pays et d’abandon de la France pour les artistes scandinaves qui se seraient tournés de nouveau vers Paris seulement en 1908 avec l’arrivée des élèves d’Henri Matisse. Une étude approfondie de leur présence aux Salons parisiens a été menée afin de constater que leur nombre ne baisse pas et que les départs des uns sont aussitôt comblés par l’arrivée d’autres artistes scandinaves. À travers l’examen de la taille et de l’activité de cette communauté d’artistes installés en France durant ces deux décennies, dites nationalistes, il s’avère que l’hypothèse du retour vers la Scandinavie dans les années 1890 est un mythe créé par une historiographie faussée. La plupart des artistes scandinaves expatriés en France de 1889 à 1908 menèrent des carrières couronnées de succès dans un environnement cosmopolite et international. Les raisons de la mauvaise interprétation de cette période de l’histoire de l’art scandinave ont été analysées à travers les ouvrages d’histoire de l’art anciens et actuels. D’autres investigations ont été entreprises, basées sur la correspondance de ces artistes principalement conservée à l’Académie Royale des Beaux-Arts de Suède et dans les archives d’Auguste Rodin, ainsi que sur l’étude de leur accueil critique en France. Elles démontrent que la colonie scandinave de Paris de ces années-là a été exclue des expositions organisées en France par leurs propres pays et que la carrière de ces artistes expatriés, ainsi que le rôle de la France, ont été minimisés dans l’histoire de l’art scandinave. / This dissertation is about the presence of Swedish and Norwegian artists in France during the years 1889 to 1908. Traditionally these years have been considered as a period when Scandinavian artists left France to return to their homelands and according to this traditional view, they only returned to Paris and French influence with the arrival of Henri Matisse’s students around 1908. A thorough study of their presence in the Parisian Salons has been conducted which determines that their numbers do not decrease and that the departure of certain Scandinavian artists was balanced by the arrival of others. By examining the size and the activity of this artistic community in France during these two so-called nationalistic decades, it appears in fact that the hypothesis about the return to Scandinavia in the 1890’s is a myth created by a distorted historiography. Most Scandinavian expatriate artists living in France between 1889 and 1908 led successful careers in a cosmopolitan and international environment. The reasons for the misinterpretation of this period in Scandinavian art history have been analysed using historical and current texts and art history handbooks. Further investigation based on the correspondence of these artists, kept chiefly by the Royal Swedish Academy of Fine Arts and in the archives of Auguste Rodin, as well as the study of their critical reception in France, have shown that the Parisian colony of Scandinavian artists has often been excluded from exhibitions organized in France by their home countries and that the career of these expatriate artists as well as the role of France during this period has been minimized in Scandinavian art history.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents innovative methods for detection and correction of the distorted portions of the secondary current waveforms, which occur due to the core saturation of current transformers (CTs). The detection technique is based on the analysis of the plans formed by the secondary current (i2) and their difference-functions (deln). The distance between consecutive points in these plans has a significant increase when saturation occurs, bucking the trend during the undistorted intervals, which are not corrupted by CT saturation. Additionally, the proposed correction of these signals is based on a technique of curve fitting by least squares, which uses the frequency signal estimated from the secondary current signals as a parameter of compensation. The aforementioned frequency signal is estimated using the Mathematical Morphology operators of dilation and erosion, which are used to estimate future values of the α and β signals obtained from the Clarke Transform. Computational simulations of short circuits were performed to obtain the secondary current signals distorted by CT saturation. The detection method was evaluated in terms of the ability to identify saturation intervals and its speed of response. Moreover, the correction technique was evaluated in terms of the compensation accuracy and its processing time. Calculations of transient error and the use of a full cycle Fourier filter were the basis for the qualitative analysis of the performance of the correction technique. The tests revealed that the combination of the proposed techniques ensures excellent accuracy during correction signals distorted by saturation, showing that the proposals constitute a robust tool for use in numerical relays, increasing the reliability of protection schemes in situations involving the saturation of TCs. / Este trabalho apresenta métodos inovadores para detecção e correção dos trechos distorcidos da forma de onda dos sinais da corrente secundária, que ocorrem em virtude da saturação do núcleo dos transformadores de corrente (TCs). A técnica de detecção é fundamentada na análise dos planos formados pela corrente secundária (i2) e suas funções-diferença (deln). A distância entre pontos consecutivos nesses planos tem um aumento significativo quando a saturação ocorre, contrariando a tendência durante os intervalos não distorcidos por saturação. Além disso, a proposta para correção desses sinais utiliza uma técnica de ajuste de curvas por Mínimos Quadrados, a qual emprega o sinal de frequência estimado a partir dos sinais da corrente secundária como parâmetro de compensação. O referido sinal de frequência é estimado por uma metodologia fundamentada em Morfologia Matemática, cujos operadores de dilatação e erosão são utilizados para estimação de valores futuros dos sinais α e β, obtidos a partir da Transformada de Clarke. Simulações computacionais de curtos-circuitos foram realizadas para a obtenção dos sinais da corrente secundária distorcida por saturação. O método de detecção foi avaliado em termos da capacidade de reconhecimento dos intervalos de saturação e velocidade de resposta. Ainda, a técnica de correção foi avaliada com relação à precisão da compensação e do tempo de processamento. Cálculos de erro transitório e a utilização de um filtro de Fourier de ciclo completo foram a base para a análise qualitativa do desempenho da técnica de correção. Os testes revelaram que a combinação entre as técnicas propostas garante excelente precisão durante a correção dos sinais distorcidos por saturação, mostrando que as propostas constituem uma ferramenta robusta para aplicação em relés numéricos, aumentando a confiabilidade dos esquemas de proteção em situações que envolvam a saturação dos TCs.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work aims to evaluate the performance of some methods used to detect and correct the distorted portions of the secondary current signal waveform, which occur due to the core saturation of current transformers. Such methods are presented didactically divided among techniques existing in the specialized literature and new methodologies proposed. Involving various mathematical tools, methods of correction and detection were combined for the analyzed cases. Computer simulations of faults were made to obtain secondary current signals distorted by saturation, allowing the evaluation of these methodologies. The detection methods were evaluated in terms of the ability to identify saturation intervals and speed response. Moreover, the correction techniques were evaluated in terms of compensation accuracy and their processing time. Transient error calculations and the use of a full cycle Fourier filter were the basis for the qualitative analysis of the correction techniques performance. In each case analyzed, different performances were verified for the combinations tested. It was found that differences in detection time instants of the distorted portions provide different rates of error to the methodologies that are associated with saturation detectors. In this context, one of the techniques proposed for detection of distorted sections showed good precision, ensuring low errors for one of the associated correction methodologies in all the analyzed cases. Also, it was found that methods based on Least Squares have good accuracy for the correction of signals distorted by saturation. / Este trabalho visa avaliar o desempenho de alguns métodos para detecção e correção dos trechos distorcidos da forma de onda dos sinais de corrente secundária, que ocorrem em virtude da saturação do núcleo dos transformadores de corrente. Tais métodos são apresentados didaticamente, divididos entre técnicas existentes na literatura especializada e novas propostas. Envolvendo variadas ferramentas matemáticas, as metodologias de correção e detecção foram combinadas para análise de casos. Simulações computacionais de curtoscircuitos foram realizadas para a obtenção dos sinais da corrente secundária distorcida por saturação. Os métodos de detecção foram avaliados em termos da capacidade de reconhecimento dos intervalos de saturação e velocidade de resposta. Além disso, as técnicas de correção foram avaliadas em termos da precisão da compensação e do tempo de processamento. Cálculos de erro transitório e a utilização de um filtro de Fourier de ciclo completo foram a base para a análise qualitativa do desempenho das técnicas de correção. Em cada caso analisado, diferentes desempenhos foram verificados. Observou-se que diferenças nos instantes de detecção dos trechos distorcidos propiciam diferentes margens de erro às metodologias de correção, que são associadas aos detectores de saturação. Nesse contexto, uma das técnicas propostas para detecção dos trechos distorcidos apresentou boa precisão, garantindo que uma das metodologias de compensação, a qual foi associada, obtivesse erros relativamente baixos para todos os casos analisados. Também, verificou-se que as metodologias fundamentadas em Mínimos Quadrados possuem boa precisão durante a correção dos sinais distorcidos por saturação.

<div>Hearing loss hinders the communication ability of many individuals despite state-of-the-art interventions. Animal models of different hearing-loss etiologies can help improve the clinical outcomes of these interventions; however, several gaps exist. First, translational aspects of animal models are currently limited because anatomically and physiologically specific data obtained from animals are analyzed differently compared to noninvasive evoked responses that can be recorded from humans. Second, we lack a comprehensive understanding of the neural representation of everyday sounds (e.g., naturally spoken speech) in real-life settings (e.g., in background noise). This is even true at the level of the auditory nerve, which is the first bottleneck of auditory information flow to the brain and the first neural site to exhibit crucial effects of hearing-loss. </div><div><br></div><div>To address these gaps, we developed a unifying framework that allows direct comparison of invasive spike-train data and noninvasive far-field data in response to stationary and nonstationary sounds. We applied this framework to recordings from single auditory-nerve fibers and frequency-following responses from the scalp of anesthetized chinchillas with either normal hearing or noise-induced mild-moderate hearing loss in response to a speech sentence in noise. Key results for speech coding following hearing loss include: (1) coding deficits for voiced speech manifest as tonotopic distortions without a significant change in driven rate or spike-time precision, (2) linear amplification aimed at countering audiometric threshold shift is insufficient to restore neural activity for low-intensity consonants, (3) susceptibility to background noise increases as a direct result of distorted tonotopic mapping following acoustic trauma, and (4) temporal-place representation of pitch is also degraded. Finally, we developed a noninvasive metric to potentially diagnose distorted tonotopy in humans. These findings help explain the neural origins of common perceptual difficulties that listeners with hearing impairment experience, offer several insights to make hearing-aids more individualized, and highlight the importance of better clinical diagnostics and noise-reduction algorithms. </div>

La nucléosynthèse du fluor n'est pas encore clairement expliquée. Plusieurs scénarios prédisent que la réaction de capture alpha radiative sur l'azote 15 est la principale réaction de production de fluor. Dans l'expression du taux de cette réaction un paramètre essentiel est manquant, la largeur partielle alpha de la résonance sur le niveau d'énergie E = 4,377 MeV du fluor 19. Une mesure directe est exclue du fait de la très faible valeur attendue de la section efficace. Nous avons déterminé cette largeur alpha par le biais d'une réaction de transfert et une analyse en FR-DWBA (Finite Range Distorted Wave Born Approximation) dans un modèle simplifié de cluster alpha. Cette expérience a été effectuée avec un faisceau de lithium 7 accéléré à 28 MeV sur une cible gazeuse d'azote 15. Les 16 premiers niveaux du fluor ont été étudiés. Les facteurs spectroscopiques ont été extraits pour la majorité de ces niveaux. Les largeurs alpha des niveaux au-dessus du seuil ont été déterminées. Plusieurs largeurs alpha ont été comparées avec des valeurs publiées de mesures directes et l'écart reste dans la plage d'incertitude que nous avons estimée (facteur 2). La largeur alpha du niveau d'énergie E = 4,377 MeV a été déterminée, sa valeur est environ 60 fois plus faible que la valeur utilisée jusqu'à ce jour. L'influence de ce nouveau taux est observée principalement dans les étoiles dites AGB (Asymptotic Giant Branch) lors de phénomènes de pulsations thermiques. Dans ce modèle l'impact de nos mesures est sensible.

[pt] A presente Tese busca problematizar algumas das relações entre a racionalidade e as práticas argumentativas características do ensino superior brasileiro, principalmente no contexto da pós-graduação. Para este intento, a investigação da teoria do filósofo alemão Jurgen Habermas tornou-se fundamental, principalmente a análise das regras do discurso. Estas regras foram consideradas, neste trabalho, como elementos norteadores da racionalidade comunicativa e discursiva. Um dos focos centrais da Tese foi discutir os problemas relativos à implementação fática das ideias habermasianas. Com este intuito, tornou-se necessário aprofundar a investigação sobre o conceito de comunicação sistematicamente distorcida e articular outras observações, provenientes de patamares teóricos distintos: da psicologia cognitiva, a teoria sobre protótipos; da psicologia social destacou-se a noção de estereótipos; da psicologia genética piagetiana, o conceito de esquemas; da reflexão hermenêutica, o círculo hermenêutico. Ao final, reflexões gerais sobre a argumentação procuram evidenciar as implicações deste estudo para processos educacionais do ensino superior. / [en] This thesis aims to discuss some of the relationships between rationality and argumentative practices characteristic of Brazilian higher education, especially in the context of graduate studies. For this purpose, the investigation of the theories of the German philosopher Jurgen Habermas is crucial, especially his analysis of the rules of discourse. These rules were considered in this work as the guiding elements of communicative and discursive rationality. A central focus of the thesis is to discuss issues related to the implementation of Habermas s ideas. For this purpose, it became necessary to investigate the concept of systematically distorted communication and articulate other observations from different theoretical perspectives: the theory of prototypes in cognitive psychology; the notion of stereotypes in social psychology; the concept of schemas in Piaget s genetic psychology; and the hermeneutic circle in hermeneutics. The thesis concludes with general reflections on argumentation intended to clarify the implications of this study for educational processes in higher education.

Cette étude a pour objectif principal d’établir une stratégie de modélisation robuste, fiable et performante pour décrire des propagations de fissures d’échelle centimétrique en régime ductile dans des composants industriels. Le modèle d’endommagement de GTN écrit en grandes déformations est utilisé pour modéliser l’endommagement ductile. Ce modèle conduit généralement à une localisation de la déformation, conformément à l’expérience. L’échelle caractéristique de ce phénomène est introduite dans les équations de comportement via l’adoption d’une formulation non locale.Sur le plan numérique, ce modèle non local rend bien compte de la localisation dans une bande d’épaisseur donnée lorsqu’on raffine suffisamment le maillage. Par ailleurs, le problème de verrouillage numérique associé au caractère initialement isochore de la déformation plastique est limité en utilisant une formulation à base d’éléments finis mixtes. Enfin, la distorsion des éléments totalement cassés (i.e. sans rigidité apparente), qui pourrait nuire à la bonne convergence des simulations numériques, est traitée par une régularisation viscoélastique.L’ensemble de ces ingrédients sont appliqués pour simuler la propagation de fissure dans un milieu infini plasticité confinée), de sorte à établir un lien avec les approches globales en J-Δa. L’émoussement, l’amorçage et la (grande) propagation de fissure sont bien prédits. Le modèle est également appliqué à une tuyauterie métallique testée en grandeur réelle dans le cadre du projet européen Atlas+. Après une phase d’identification des paramètres sur éprouvette, les réponses globales et locales d’autres éprouvettes et du tube sont confrontés aux résultats expérimentaux. Ces résultats illustrent le degré de robustesse, de fiabilité et de performance qu’on peut attendre du modèle. / The major goal of this work is to establish a robust, reliable and efficient modeling technique so as to describe ductile tearing over a distance of several centimeters in industrial cases. The GTN damage model expressed in the context of finite strains is chosen to model ductile damage. Generally, the model leads to strain localization in agreement with experimental observations. The characteristic length scale of this phenomenon is introduced into the constitutive equations through the use of a nonlocal formulation.On a numerical ground, the nonlocal model controls the width of the localization band as soon as the mesh is sufficiently refined. Besides, the issue of volumetric-locking associated with plastic incompressibility is handled using a mixed finite element formulation. Finally, the distortion of broken elements (i.e. without any stiffness), which may affect the computational convergence of numerical simulations, is treated using a viscoelastic regularization.The improved GTN model is applied to simulate crack propagation under small-scale yielding conditions, so as to establish a relation with the global (J-Δa) approach. Crack tip blunting, crack initiation and (large) crack propagation are well captured. The model is also applied to a full-scale metallic pipe in the framework of the UE project Atlas+. After a phase of parameter calibration based on the experimental results on some small specimens, the global and local responses of other small specimens and of the full-scale pre-cracked pipe are compared with the experimental results. The results illustrates the robustness, the reliability and the efficiency of the current model.