No description available.

Ulm, Univ. Diss., 2006.

Thesis (M.S.)--Ohio University, August, 1997. / Title from PDF t.p.

[pt] Em geral, o movimento de corpos se dá em ambiente com barreiras podendo ocorrer colisões. Para que seja possível fazer previsões da dinâmica é necessário saber o que acontece quando um corpo colide. O problema é portanto: conhecida a dinâmica do corpo pré-colisão e as propriedades dos corpos que colidem, prever a dinâmica pós-colisão. Os primeiros trabalhos publicados sobre o assunto datam de 1668 e, até 1984,os modelos existentes pareciam satisfatórios. Porém a aplicação de um desses modelos a um problema simples apresentou geração de energia. Desde então, um grande número de trabalhos tem aparecido na literatura. A tese trata de problema de colisões planas, discute criticamente os modelos da literatura comparando-os através de uma generalização por nós desenvolvida e propõe um novo modelo que engloba alguns dos modelos da literatura. Mostramos os principais problemas de alguns dos modelos e discutimos questões de existência e unicidade. Simulações feitas num programa por nós desenvolvido são apresentadas e ajudam a entender a influência dos coeficientes constitutivos. A validação dos resultados é realizada através de resultados experimentais colhidos da literatura. / [en] In general the motion of a body takes place in a confined environment and collision of the body with the containing wall is possible. To predict the dynamics of a body in this conditions one must know what happens in a collision. The problem is then: known the pre-collision dynamics of the body and the properties of the body and the wall one want to predict the post-collision dynamics. This problem is quite old and it appeared in the literature in 1968. Up to 1984 it seemed that Newton model was enough to solve the problem. But it was found that this was not the case and a renewed interest in the problem appeared. This thesis treats the problem of plan collisions of rigid bodies and tries to classify the differents models and to compare them. A new model is presented and old results are shown in a new framework.

Abstract In this report I critically evaluate Kripke’s rejection of the possibility of contingently true statements of identity between names. I extract his argument for this view from his book Naming and Necessity and his article “Identity and Necessity”. I discuss debates in the relevant literature about Kripke’s positions on naming, reference and modality, as these issues influence Kripke’s conclusions about statements of identity between names. I provide my own arguments for rejecting Kripke’s conclusions and accepting that there can be contingently true statements of identity between names.

No description available.

No description available.

This thesis is concerned with the simulation model of an OPAT dummy rider on a Norton motorcycle in different configured impacts with a rigid barrier. The mathematical equations used in describing the mass-spring-damper-based impacts have been given. The software used in designing the mathematical model have also been outlined. The simulation model was then calibrated against full scale crash tests by means of film analysis and the processed digitised measurements. This led to the investigations into numerical processing of differentiation and integration. A parametric study was also conducted to examine injury to the dummy rider based on some varying parameters. The simulation model was further verified by different configurations and also an introduction of an airbag. Finally, the model was extended to a HYBRID3 dummy rider on the same motorcycle in different configured impacts with a motor car. It is hoped that after the validations and verifications have been performed to examine the robustness of the simulation model, it can assist in the analyses of motorcycle impacts with the less frequent need of conducting a full scale crash test, so that safety design of a motorcycle can be established.

by Wong Hin Lau. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 118-126).

Consider a polyhedral surface in three-space that has the property that it can change its shape while keeping all its polygonal faces congruent. Adjacent faces are allowed to rotate along common edges. Mathematically exact flexible surfaces were found by Connelly in 1978. But the question remained as to whether the volume bounded by such surfaces was necessarily constant during the flex. In other words, is there a mathematically perfect bellows that actually will exhale and inhale as it flexes? For the known examples, the volume did remain constant. Following an idea of Sabitov, but using the theory of places in algebraic geometry (suggested by Steve Chase), Connelly et al. showed that there is no perfect mathematical bellows. All flexible surfaces must flex with constant volume. We built several models to illustrate the above theory, in particular, we built a model of the cubeoctahedron after a suggestion by Walser. This model is cut at a line of symmetry, pops up to minimize its energy stored by 4 rubber bands in its interior, and in doing so also maximizes its volume. Three MATLAB programs were written to illustrate how the cuboctahedron is obtained by truncation, how the physical cuboctahedron moves and how the motion of the cubeoctahedron can be described if self-intersection is possible.