Abstract The rolling is an efficient and economical approach for the manufacturing of strip or plate metals, it plays an important role because of its versatility and its high production rate in the manufacture of various products with uniform cross-sectional area. Without the knowledge of the influences of the variables such as friction conditions, material properties, and workpiece geometry on the process mechanics, it will not be possible to design and control the equipment adequately, or to predict and prevent the occurrence of failures. According to modeling by numerical has become a major tool in rolling research. By using the proper criterion, de-pending upon the production requirements along with the modeling results, the process efficiency, productivity and quality can be increased and the down time of the mill and cost operation can be reduced. In this study, investigated that it do not consider to work hardening and consider to work hardening during the rolling process from Von Karman theory. We can realize friction coefficient, reduction ratio, rolling force, rolling torque, neutral point, and pressure distribution relation, then from measuring rolling force, torque, neutral point can inverse to solve friction coefficient and pressure distribution. Result that we found the error of direct and inverse solution about rolling friction coefficient was less than 5 %, and the coef-ficient of friction was found to increase with reduction and rolling force and neutral point.

Solar cells are at the frontier of renewable energy technologies. Photovoltaic energy is clean, reusable, can be used anywhere in our solar system and can be very well integrated with power distribution grids and advanced technological systems. Thin film solar cells are a class of solar cells that offer low material cost, efficient fabrication process and compatibility with advanced electronics. However, as of now, the conversion efficiency of thin film solar cells is inferior to that of thick crystalline cells. Research efforts to improve the performance bottlenecks of thin film solar cells are highly motivated. A class of techniques towards this goal is called light trapping methods, which aims at improving the spectral absorptivity of a thin film cell by using surface texturing. The precise mathematical and physical characterization of these techniques is very challenging. This dissertation proposes a numerical and computational framework to optimize, design, and fabricate efficient light trapping structures in thin film solar cells, as well as methods to verify the fabricated designs. The numerical framework is based on the important "inverse optimization" technique, which is very is widely applicable to engineering design problems. An overview of the state-of-the-art thin film technology and light trapping techniques is presented in this thesis. The inverse problem is described in details with numerous examples in engineering applications, and is then applied to light trapping optimization. The proposed designs are studied for sensitivity analysis and fabrication error, as other aspects of the proposed computational framework. At the end, reports of fabrication, measurement and verification of some of the proposed designs are presented. / text

Novel approaches to the determination of material properties and damage parameters of fibre-matrix composites using inverse analysis are presented. In inverse analysis system identification techniques are used to update some form of mathematical model (normally a FE model) using data from an over-determined number of tests. Initially, pultruded GFRP box-section beams are subjected to a quasi-static impact or bending crush. The results of the impact tests are presented to corroborate those in the literature that have been obtained using simpler geometries such as flat plates. In the first form of inverse analysis, a model-updating approach is applied to progressive tearing damage in pultruded composite box-section beams. The difference between empirical data (from a programme of three-point bend tests) and a FE model is minimised by a genetic algorithm to produce an optimal solution. The solution is in the form of a FE model that can be subsequently analysed to determine the structural integrity of the damaged specimen. Secondly, a unidirectional composite disc from the same GFRP pultruded section is analysed in diametral compression to both verify and improve the validity of the diametral compression test in determining the material properties. Coupons are cut from damaged specimens and test results are presented. The strain distribution within the disc is compared to known laminate theory in order to process data obtained by speckle-shearing interferometry. Finally, speckle-shearing interferometry is used to characterise the response of the pultruded box-section exhibiting progressive tearing damage. Out-of-plane displacement-gradient data is used to determine and characterise damaged regions or flaws. The differences between the need to perform it programme of unequivocal static tests and the collection of full-field optical data are highlighted. It is shown that the shearing interferometry approach is the superior method.

O Homem tem desde o passado, tentado controlar a natureza. Um dos meios utilizados para isto, é sua observação do mundo. Através desta observação, tenta entender os fenômenos da natureza para fazer teorias e modelos. Charles Darwin, em seu trabalho Teoria da Evolução das Espécies, nos dá informações para o conhecimento de uma das mais importantes leis da natureza : sobrevive para a próxima geração o individuo mais forte. O Algoritmo Genético, pesquisado neste trabalho, é o exemplo disso. John Holland fez um Algoritmo Genético baseado na teoria de Darwin, que procura pelas melhores soluções para resolver um problema específico. Nada mais do que a simulação da teoria de Darwin. Nós pretendemos neste trabalho, estudar o Algoritmo Genético de Holland e através dele, analisar uma estrutura para encontrar seus parâmetros elásticos. / The men has since the past, tryed to control the nature. One of the way utilized for this, is his observation of the world. Through his observation, tries to understand the nature\'s fenomena, to making theories and models. Charles Darwin, in his work Theories of Species Evolution, gives us informations for the knowledges of one of the most important nature\'s laws: survives to the next generation the strongest individual . The Genetic Algorithm, the search in this work, is the example of this. John Holland, did a Genetic Algorithm. based in Darwin\'s Theories, that looks for the best solutions to solve a specific problem. Nothing else, of the simulation of the Darwin\'s theories . We intend in this work, to study the Holland\'s Genetic Algorithms and through it, to analyses a structure for find its elastic parameters.

O Homem tem desde o passado, tentado controlar a natureza. Um dos meios utilizados para isto, é sua observação do mundo. Através desta observação, tenta entender os fenômenos da natureza para fazer teorias e modelos. Charles Darwin, em seu trabalho Teoria da Evolução das Espécies, nos dá informações para o conhecimento de uma das mais importantes leis da natureza : sobrevive para a próxima geração o individuo mais forte. O Algoritmo Genético, pesquisado neste trabalho, é o exemplo disso. John Holland fez um Algoritmo Genético baseado na teoria de Darwin, que procura pelas melhores soluções para resolver um problema específico. Nada mais do que a simulação da teoria de Darwin. Nós pretendemos neste trabalho, estudar o Algoritmo Genético de Holland e através dele, analisar uma estrutura para encontrar seus parâmetros elásticos. / The men has since the past, tryed to control the nature. One of the way utilized for this, is his observation of the world. Through his observation, tries to understand the nature\'s fenomena, to making theories and models. Charles Darwin, in his work Theories of Species Evolution, gives us informations for the knowledges of one of the most important nature\'s laws: survives to the next generation the strongest individual . The Genetic Algorithm, the search in this work, is the example of this. John Holland, did a Genetic Algorithm. based in Darwin\'s Theories, that looks for the best solutions to solve a specific problem. Nothing else, of the simulation of the Darwin\'s theories . We intend in this work, to study the Holland\'s Genetic Algorithms and through it, to analyses a structure for find its elastic parameters.

Deterministic methods have been used in geotechnical engineering for a long period, such as slope stability calculations. However, only applying deterministic methods is subjective and imperfect. There is a demand to develop a systematic methodology to link the assessed slope stability and field measurement data, which is also known as inverse analysis and forward calculation. Based on the Nya Slussen project, this thesis includes the development of a methodology, deterministic calculation for 4 cross sections using finite element program Plaxis 2D and probabilistic calculation for one section. Deterministic analyses showed satisfying results for all the studied cross sections since their factors of safety exceeded the minimum requirement. In probabilistic design, three parameters were found to have the most uncertainties through sensitivity analysis (undrained shear strength of clay, Young’s modulus of clay and friction angle of fill). Inverse analysis was done by testing different values of them in Plaxis and to try to match the displacement components provided by field measurement. After finding the best optimization for all the parameters, forward calculation gave a final factor of safety. It is suggested that both of the methods should be utilized together for better assessment.

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24174号 / 理博第4865号 / 新制||理||1696(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)准教授 成瀬 元, 准教授 堤 昭人, 教授 野口 高明 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

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A new inverse analysis method is presented to identify parameters of heat convection in microelectronic packages. This approach adopts a modified Micro Genetic Algorithm (µGA) in finding the global optimum of parameters. A reduced-basis approach is introduced in the forward heat transfer analysis so as to significantly improve the efficiency in the calculation. Different identification procedures are employed to identify heat convection coefficients of a typical microelectronic package. Comparisons between different algorithms are performed. Results show that the use of the reduced-basis method together with the modified µGA outperforms the conventional GAs significantly. The presented method of coefficient identification is ideal for practical applications. It is efficient enough even for online analysis of both forward and inverse problem. / Singapore-MIT Alliance (SMA)

The dynamic properties of soil are normally inferred from laboratory tests on collected samples or from empirical relations. The soil properties measured in the field can be very different from those predicted from laboratory tests. It is very difficult to determine directly in the field the variation of the shear modulus and damping with the level of excitation (level of strains). This remains today a major gap in our knowledge and our ability to conduct reliable seismic analyses. The main objective of this study is to assess the feasibility of determining reliably in situ the shear modulus and damping of the soil as functions of the level of strains, developing a method to compute these properties from the measured data and providing practical recommendations for the use of the procedure. To achieve this objective, extensive and comprehensive sets of experimental and analytical studies were conducted in parallel. Some numerical analyses were performed to provide a better understanding for performing in situ tests with the newly developed vibroseis loading systems. In addition, the dynamic response of a surface foundation in vertical vibration were studied. This dissertation mostly focuses on the numerical aspects of the problem while some experimental data are also studied and utilized. Field tests were conducted to estimate shear moduli of silty sands at two sites, the Capital Aggregate Quarry and the Texas A&M University sites. Estimated nonlinear shear moduli presented very consistent trends regardless of the analysis methods and test sites. They showed larger elastic threshold shear strains, 1.5 × 10−3 % for the Capital Aggregate Quarry site and 2 × 10−3 % for the Texas A&M University site, than the mean of shear modulus curve for cohesionless soils proposed by Seed and Idriss (1970). Estimated moduli closely followed the mean of Seed and Idriss (1970) at strains larger than 6 × 10−3 % for both sites. Internal damping ratio can also be estimated if additional data are gathered from in situ tests in the future.