京都大学 / 新制・課程博士 / 博士(工学) / 甲第24817号 / 工博第5160号 / 新制||工||1986(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 杉野目 道紀, 教授 生越 友樹, 教授 大内 誠 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

No / An investigation of the surface current distribution in a normal-mode helical antenna (NMHA) is reported. This enables precise prediction of the performance of NMHAs, since traditional wire-antenna simulations ignore important details, such as non-uniform and transverse current distributions. A moment-method formulation is developed, using two-dimensional basis functions to represent the total non-uniform surface current distribution over the surface of the wire of the helix. Piecewise-sinusoidal basis functions are employed in two normal directions, with an exact kernel formulation and application of Galerkin's solution method. The numerical solution of the singular integrals associated with self-impedance terms was computed with a very low relative error. The surface current distribution was computed for different helix geometries. It was found that the axially-directed component of the current distribution around the surface of the wire was highly non-uniform and that there was also a significant circumferential current flow due to inter-turn capacitance, both effects that are overlooked by standard filamentary current representations.

Magistro baigiamajame darbe tiriamos nevienalyčių plačiajuosčių periodinių sistemų užtvarinės savybės. Aptariamos periodinės sistemos ir jų charakteristikų skaičiavimo metodai. Nevienalyčių periodinių savybių tyrimui panaudoti du modeliai. Pradžioje nagrinėjamos periodinės ilgosios linijos savybės, vėliau taikomas spiralinės sistemos modelis. Modelių analizė atliekama klasikiniu, matriciniu ir daugialaidžių linijų metodais. Taikomas kompiuterinis modeliavimas. Sudarytos įėjimo varžos, perdavimo ir lėtinimo koeficientų, vėlinimo laikų bei pereinamosios charakteristikos skaičiavimo programos. Parodyta, kad linijos su periodiniais netolygumais įgyja užtvarinio filtro savybes, kurios ryškėja, didėjant sistemos nevienalytiškumui. / In order to reveal general properties of the structures, containing periodical inhomogeneities, the inhomogeneous electromagnetic line and the inhomogeneous helical retard structure are considered. The overview of periodical systems and methods of their analysis are presented. The structures, containing periodical inhomogeneities, are analyzed using classical, matrix and multiconductor line methods. The programs for calculation of line input impedance, transfer coefficient, delay coefficient and width of the stop-band are developed. The results show that the stop–band appears due to periodical inhomogeneities and the width of the stop-band and the attenuation in it depend on intensities of periodical inhomogeneities.

No description available.

L'auto-assemblage dynamique est une méthode puissante pour accéder à des édifices moléculaires fonctionnels complexes. Son application à la construction de moteurs moléculaires par le biais de la maîtrise des échelles de temps ouvre la voie à des générations de nano-machines de plus en plus sophistiquées pouvant spontanément renouveler leurs composants ou les changer pour d'autres. La première partie de ce manuscrit est axée sur le design d’hélices d’oligoamides aromatiques qui peuvent s’enrouler le long d’un axe et glisser rapidement le long de celui-ci avant de se dérouler. Le second volet de cette thèse est consacré à la mise en évidence d’un mouvement qui est caractérisé pour la première fois à l’échelle moléculaire: le vissage. Le dernier axe de recherche développé dans ce manuscrit concerne la mise en évidence d’un intermédiaire cinétique de type foldaxane se transformant progressivement en un complexe hôte-invité 2:2 thermodynamiquement stable. / Dynamic self-assembly is a powerful method for fabricating complex, functional molecular structures. Its application to the construction of molecular motors through the control of timescales paves the way for new generations of nano-machines, in which sophisticated components can be spontaneously renewed or changed by others. The first part of this thesis focuses on the design of aromatic oligoamides that can slowly wind along an axis and shuttle along it before unfolding. The second chapter is devoted to the detection of a movement that is characterized for the first time at the molecular level: the screwing motion. The last line of research developed in this manuscript concerns the identification of a long-lived kinetic supramolecular by-product based on foldaxane architecture, which gradually transforms into a thermodynamically favored 2:2 host-guest complex.

La fonction d’une protéine dépend dans une large mesure de sa structure tridimensionnelle, c’est pourquoi de nombreux chercheurs se sont passionnés pour la synthèse des foldamères, molécules de synthèse, bioinspirées, capables d’adopter des structures repliées bien définies. Parmi les différentes classes de foldamères, les oligourées aliphatiques étudiées dans notre laboratoire s’organisent pour former des structures hélicoïdales voisines de l’hélice α des polypeptides naturels. Pour développer des hélices fonctionnelles mimes de structures biologiques, il est intéressant de mieux comprendre les règles de leur repliement, par exemple en modifiant la nature des unités monomériques. Au cours de cette thèse, nous avons donc testé la compatibilité de la géométrie de l’hélice d’oligourée avec des résidus comportant de fortes contraintes stériques comme des groupements gem-diméthyles et des cycles pyrrolidines. En utilisant les résidus pyrrolidine, nous avons ensuite développé une nouvelle stratégie de synthèse par condensation de segments permettant de concevoir des hélices de grande taille (jusqu’à 4 nm). Grâce à cette nouvelle stratégie de synthèse et aux informations obtenues sur la stabilité des hélices nous avons pu concevoir des architectures plus complexes (structures quaternaires) résultant de l’assemblage programmé d’hélices hydrosolubles. / The biological functions of proteins are mainly correlated to their tridimensional structure. For this reason a large number of chemists are interested in the synthesis of foldamers, which are bioinspired artificial molecules possessing well-defined folded conformations. In particular, in our laboratories we focused on the study of oligourea foldamers, which form well-defined and remarkably stable helical structures, analogous to the natural polypeptides α-helix. In order to develop artificial functional helices able to mimic biological structures, it is interesting to understand the rules governing their folding, for example by comparing different residues substitution patterns. During this thesis we have investigated the compatibility of the helix geometry with residues containing steric constraints, such as gem-dimethylated units or pyrrolidine cycle. We have developed a new segment condensation strategy based on these residues, which enabled the facile synthesis of long helical segments (up to 4 nm). The use of this novel approach, combined with the information acquired on helical stability allowed us to produce more complex architectures (quaternary structures) resulting from the controlled assembly of water soluble helices.

Les foldamères de type oligopyridine biscarboxamide constituent une famille d’oligomères synthétiques pouvant adopter une structure hélicoïdale et s’hybrider pour former des hélices doubles. Ce travail a eu pour objectif de synthétiser une nouvelle génération de foldamères π-fonctionnels porteurs de groupements photoactifs ou électroactifs, d’étudier les facteurs gouvernant l’équilibre entre hélice simple et hélice double, d’analyser l’impact de cet équilibre sur les propriétés optiques, et enfin de mettre en place un nouveau type de stimulus permettant de contrôler cet équilibre. Deux foldamères photoactifs dotés d’unités Disperse Red, ont été synthétisés. Leurs structures cristallographiques confirment la formation de structures hélicoïdales. Un choix précis du solvant permet d’orienter sélectivement l’équilibre vers la formation d’une hélice simple ou double.Le contrôle de l’équilibre d’hybridation par dilution permet de moduler l’activité en Génération de Seconde Harmonique du foldamère. En outre, la cavité générée par l'hélice permet la reconnaissance de divers anions. Enfin, les premiers efforts fournis pour induire une hélicité donnée à ces foldamères par voie supramoléculaire sont décrits. Par ailleurs, un foldamère électroactif fonctionnalisé par deux unités tétrathiafulvalène (TTF) a été synthétisé selon une méthodologie originale. La présence des unités TTF permet un contrôle redox inédit de la structuration du foldamère, par dimérisation de cations radicaux. Le concept a été élargi via l’immobilisation d’un foldamère sur surface d’or (SAMs). Enfin, une capsule électroactive capable de complexer l’acide tartrique a également été synthétisée et caractérisée. / Oligopyridine biscarboxamide-based foldamers constitute a family of synthetic oligomers that can fold into helical structures and hybridize to form double helices. This work aims at synthesizing a new generation of π-functionalized foldamers featuring photoactive and electroactive moieties, in order: to study the factors governing the equilibrium between simple and double helices, to analyze the impact of this equilibrium on the optical and recognition properties, and to set up a new type of stimulus to control this equilibrium. Two photoactive foldamers of different lengths and bearing two Disperse Red units were synthesized. Their crystallographic structures confirm the formation of helical structures. A precise choice of the solvent allows to drive the equilibrium towards the single or the double helix selectively.The cavity generated within the helix presents a good affinity for anions. The control over the hybridization equilibrium allows modulating the Second Harmonic Generation activity. Eventually, our first efforts to control the helicity of these foldamers through supramolecular chiral induction are described. On the other hand, an electroactive foldamer featuring two tetrathiafulvalene (TTF) units was synthesized according to an original methodology. The presence of TTF units allows an unprecedented redox control of the structure of foldamer, by dimerization of radical cations. The concept has been extended by immobilizing a foldamère on a gold surface (SAMs). Finally, an electroactive capsule capable of complexing tartaric acid has also been synthesized and characterized.

As linhas de transmissão no Brasil são geralmente muito extensas, uma vez que os grandes centros de consumo de energia ficam distantes das usinas hidrelétricas. Por essa razão, a construção e manutenção de linhas de transmissão é de grande importância e, em uma grande porcentagem destas linhas, as estacas helicoidais são usadas como fundações. No entanto, a previsão da profundidade final de instalação destas estacas ainda é um grande desafio para os projetistas, fornecedores de estacas helicoidais e construtoras. A profundidade final destas fundações é controlada pelo torque de instalação; portanto, se o torque necessário para instalar uma estaca pudesse ser calculado com acurácia, com base em suas dimensões, e nos resultados de ensaios de investigação de solo in situ (SPT), a previsão de comprimentos de estaca para estimativas de custos, a definição de equipamentos adequados para instalação e a estimativa da quantidade de seções de estacas a serem transportadas para uma determinada linha de transmissão seriam mais acuradas. Além disso, a capacidade de carga de estacas helicoidais pode ser estimada usando os resultados do torque final de instalação. Sendo assim, para atender à necessidade de se determinar o torque de instalação de fundações helicoidais ainda na fase de projeto, um método simplificado foi desenvolvido e validado com os resultados de 752 estacas helicoidais multi-hélices instaladas em solos predominantemente arenosos, de uma linha de transmissão brasileira. O modelo desenvolvido baseia-se nos resultados de ensaios SPT e considera o efeito de instalação das estacas no solo penetrado. Nesta dissertação é apresentada uma descrição detalhada do método proposto e uma comparação entre os resultados medidos em campo e calculados pelo método. Os resultados da comparação mostram que o método proposto pode estimar com sucesso o torque de instalação de estacas helicoidais. / The transmission lines in Brazil are usually very extensive, since the centers of power consumption are often far from the most hydroelectric plants. For this reason, the construction and maintenance of transmission lines is frequent in this country, and in a large percentage of transmission lines, helical piles are used as guy wire anchors and foundations for transmission towers. However, the estimates of the final embedded depth of numerous helical piles to be used in several towers of the transmission lines is still a challenge for the designers, pile suppliers and contractors. The final depth of helical foundations is controlled by the installation torque; therefore, if the torque necessary to install a helical pile could be accurately calculated based on the pile dimensions and results of in-situ soil tests (SPT), the prediction of pile lengths for costs estimations, the definition of suitable equipment for pile installation, and the estimate of the quantity of helical piles sections to be transported for a particular transmission line would be more precise. Additionally, the uplift capacity of helical piles can be estimated using the results of final installation torque. In order to address the existed need of determining the installation torque of helical foundations during the design phase, a simplified method was developed and validated with the results of 753 multi-helix piles installed in predominantly sandy soils of a Brazilian transmission line. The model proposed is based on the results of SPT tests, and considers the installation effect of helical piles on the soil penetrated. This text presents a detailed description of such method and a comparison between measured and predicted results. The comparison shows that the method proposed can successfully estimate the installation torque of helical piles.

Este trabalho utiliza a técnica de modelagem de sistemas multicorpos para analisar o comportamento dinâmico de um vagão ferroviário de carga, trafegando sobre via tangente com desnivelamento transversal periódico. O estudo exibe a modelagem dos principais vínculos deste sistema, como o contato entre o prato e o pião, molas helicoidais e sistema de amortecimento de atrito seco da suspensão primária. A modelagem do contato entre o prato e o pião sugerida, é baseada em um modelo de elastic foundation, e utiliza a característica geométrica dos corpos em contato. O modelo dinâmico de atrito desenvolvido possui atuação bidirecional, sendo utilizado nos elementos dissipativos da suspensão. A matriz de rigidez das molas helicoidais da suspensão primária é obtida utilizando o Triedro de Frenet-Serret e o Segundo Teorema de Castigliano. O modelo matemático, confeccionado com a ferramenta de modelagem ADAMS/Rail, é composto por 90 corpos rígidos e uma caixa flexível e possui 210 graus de liberdade. A comparação dos resultados obtidos na identificação modal experimental e nas análises do modelo comprovou que as hipóteses adotadas na modelagem são aceitáveis, reforçando a utilização dos modelos multicorpos na análise dinâmica do veículo guiado. A variação da velocidade de tráfego do veículo, sobre diferentes comprimentos de irregularidade da via, proporcionou os resultados para confecção dos mapas de resposta dinâmica. Esses mapas foram traçados para o ângulo rolagem, alívio das forças no contato roda-trilho e razão L/V no rodeiro de ataque, e identificaram as regiões mais sensíveis para a rolagem harmônica. A rolagem e torção da caixa foram identificados como os movimentos principais do veículo, quando em tráfego em via com desnivelamento transversal periódico. O conjunto de prato e pião gasto aumentou a faixa de velocidade indicada como crítica para a rolagem, piorando os resultados para velocidades mais baixas. O aumento do amortecimento da suspensão primária, por meio da inclinação do lenoir link, diminuiu os valores de rolagem e do alívio em comparação ao caso nominal. A utilização do ampara-balaço de contato constante propiciou a diminuição do ângulo de rolagem, alívio das forças e da razão L/V do rodeiro na região de ressonância. O aumento do amortecimento deste vínculo, devido à mola elastomérica, proporcionou resultados ainda melhores e indicou que a alteração das características da suspensão secundária pode reduzir a amplitude do movimento de rolagem harmônica. A metodologia de análise do comportamento dinâmico proposta, através dos mapas de resposta, pode auxiliar na determinação das faixas críticas de velocidade de um vagão ferroviário de carga, no tráfego em vias cujas características típicas das irregularidades são conhecidas. Empresas do setor ferroviário podem aplicar este método no projeto de novos vagões, bem como no estudo da velocidade crítica de determinada frota já em operação. / This study uses the multibody system modeling techniques to analyze the dynamic behavior of a railway freight wagon, traveling over tangent track with periodic cross level defect. The study shows the modeling of the main links of the system, as the center plate contact, helical springs and dry friction damper. The suggested modeling of the center plate contact is based on an elastic foundation model, and uses the geometric characteristic of these bodies. The dynamic friction model developed is bidirectional, being used in the dissipative suspension elements. The stiffness matrix of the helical springs is obtained using the Frenet-Serret trihedral and the Second Castigliano Theorem. The mathematical model, developed with the software ADAMS/Rail, is composed of 90 rigid bodies and a flexible car body and has 210 degrees of freedom. A comparison of results obtained in experimental modal identification and analysis of the mathematical model showed that the assumptions made in modeling are acceptable, reinforcing the use of multibody models in dynamic analysis of rail vehicles. The traffic speed variation on different lengths of track irregularity provided the results to make the dynamic response maps. These maps were drawn to roll angle, vertical force in the wheel-rail contact and wheelset L/V and identified the most sensitive regions to harmonic roll. The roll and torsion of the car body were identified as the main movements of the vehicle, when traveling over tangent track with periodic cross level defect. The use of worn center plate increased the critical speed range to the roll motion and decreases the performance for slower speeds. The increase in the damping of the primary suspension, through the lenoir link inclination, decreased the rolling angle and wheel lift in comparison to the nominal case. The use of constant contact side bearer reduced the roll angle and wheelset L/V ratio and increased the vertical load on wheels in the resonance region. The use of elastomeric side bearer provided even better results indicating that changes of the secondary suspension characteristics can minimize the movement of harmonic roll. The methodology for analyzing the dynamic behavior, through the proposed response maps, can assist in determining the critical speed ranges of a railway freight wagon running over a track whose typical irregularities characteristics are known. Companies in the rail industry can apply this method in the design of new cars, and study the critical velocity of a given railway fleet already in operation.

Obtivemos mapas de Poincaré das linhas de força do campo magnético resultante da superposição linear do campo magnético de um plasma toroidal em equilíbrio com o campo magnético de correntes helicoidais externas. Devido a falta de simetria do campo magnético não podemos definir uma expressão analítica que descreva os mapas; estes foram, então, obtidos pela integração numérica da equação das linhas de força dVET.lxVET.B = 0. Nos mapas de Poincaré aparecem as ilhas magnéticas principais e as ilhas magnéticas secundárias. As ilhas magnéticas secundárias surgem devido a geometria toroidal. Sobre uma mesma superfície ressonante, as ilhas não tem tamanhos iguais. / Poincaré maps of magnetic field lines of a toroidal helical system were made. The magnetic field is a linear superposition of the magnetic fields produced by a toroidal plasma in equilibrium and by external helical currents. We do not have an analytical expression for the Poincaré maps since the magnetic field do not have symmetry. In order to obtain the maps, the equation dl x B = O is numerically integrated. In the Poincaré maps, the principal and the secondary magnetic islands were observed. The islands do not have equal widths in the same resonant surface.