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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.
361

Impact Analysis of Various Golf Club Head

Chen, Chau-Tang 09 July 2003 (has links)
Abstract This study aims to investigate the impact effect of varied thickness of the hitting surface and different shapes of the golf club head. The researcher integrated the computer-aided design software Pro/ENGINEER and finite element analysis software LS-DYNA to do the club head design and impact analysis. The researcher had developed five different shapes and eight different thicknesses of hitting surface of the club head model to compare the ball speed and the sweet spot of the hitting surface. He found that ball speed had increased as the hitting surface is enlarged, both laterally and vertically. He also found that thicker center surface and decreasing thickness to the rim of the thickness of the hitting surface is a better design club head. Finally, he made suggestions about the scientific information of the shape and the surface thickness of the golf club head for the designer to develop a suitable club head.
362

Mesh independent convergence of modified inexact Newton methods for second order nonlinear problems

Kim, Taejong 16 August 2006 (has links)
In this dissertation, we consider modified inexact Newton methods applied to second order nonlinear problems. In the implementation of Newton's method applied to problems with a large number of degrees of freedom, it is often necessary to solve the linear Jacobian system iteratively. Although a general theory for the convergence of modified inexact Newton's methods has been developed, its application to nonlinear problems from nonlinear PDE's is far from complete. The case where the nonlinear operator is a zeroth order perturbation of a fixed linear operator was considered in the paper written by Brown et al.. The goal of this dissertation is to show that one can develop modified inexact Newton's methods which converge at a rate independent of the number of unknowns for problems with higher order nonlinearities. To do this, we are required to first, set up the problem on a scale of Hilbert spaces, and second, to devise a special iterative technique which converges in a higher order Sobolev norm, i.e., H1+alpha(omega) \ H1 0(omega) with 0 < alpha < 1/2. We show that the linear system solved in Newton's method can be replaced with one iterative step provided that the initial iterate is close enough. The closeness criteria can be taken independent of the mesh size. In addition, we have the same convergence rates of the method in the norm of H1 0(omega) using the discrete Sobolev inequalities.
363

The piecewise linear discontinuous finite element method applied to the RZ and XYZ transport equations

Bailey, Teresa S 10 October 2008 (has links)
In this dissertation we discuss the development, implementation, analysis and testing of the Piecewise Linear Discontinuous Finite Element Method (PWLD) applied to the particle transport equation in two-dimensional cylindrical (RZ) and three-dimensional Cartesian (XYZ) geometries. We have designed this method to be applicable to radiative-transfer problems in radiation-hydrodynamics systems for arbitrary polygonal and polyhedral meshes. For RZ geometry, we have implemented this method in the Capsaicin radiative-transfer code being developed at Los Alamos National Laboratory. In XYZ geometry, we have implemented the method in the Parallel Deterministic Transport code being developed at Texas A&M University. We discuss the importance of the thick diffusion limit for radiative-transfer problems, and perform a thick diffusion-limit analysis on our discretized system for both geometries. This analysis predicts that the PWLD method will perform well in this limit for many problems of physical interest with arbitrary polygonal and polyhedral cells. Finally, we run a series of test problems to determine some useful properties of the method and verify the results of our thick diffusion limit analysis. Finally, we test our method on a variety of test problems and show that it compares favorably to existing methods. With these test problems, we also show that our method performs well in the thick diffusion limit as predicted by our analysis. Based on PWLD's solid finite-element foundation, the desirable properties it shows under analysis, and the excellent performance it demonstrates on test problems even with highly distorted spatial grids, we conclude that it is an excellent candidate for radiativetransfer problems that need a robust method that performs well in thick diffusive problems or on distorted grids.
364

Structural Analysis of Lamella Separator by the Finite Element Method

Wu, Chien-peng 10 August 2008 (has links)
In the past ten years, various sewage treatment technologies have got extensive and profound studying in the field of water pollution control in Taiwan. In each unit apparatus of the sewage disposal system, a lamella separator as the sewage treatment facility, is an important link in the structure, has irreplaceable functions. This research investigated the lamella separator structure by means of the static analysis, add factors of earthquake, and typhoon. To achieve the purpose, the researcher used the computer-aided design software Solidworks to set up this structure model. After that, he used finite element analysis software, ANSYS, to analyze the structure. This research simulated in three situations. In static, earthquake, and typhoon analysis, the researcher found the stress of the original modal is over the yielding stress of materials. So, the researcher modified the support of a model to reduce the stress. Generally, the researcher hoped that this study could provide helpful references for designers¡¦ relevant studies on lamella separator structure in the future.
365

Removing near-surface effects in seismic data : application for determination of faults in the Coastal Plain sediments /

Sen, Ashok Kumar, January 1991 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 96-97). Also available via the Internet.
366

The measurement and modeling of large particle transport in the atmosphere /

Kim, Eugene. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 111-119).
367

Processing improvement of moiré interferometry for accurate crack-tip deformation measurement

Kamil, Ridha. January 2001 (has links)
Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains v, 81 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 80-81).
368

The effects of topic choice in project-based instruction on undergraduate physical science students' interest, ownership, and motivation

Milner-Bolotin, Marina. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI's Dissertation Abstracts.
369

Efficient classification for longitudinal data /

Wang, Xianlong. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 45-50). Also available on the World Wide Web.
370

Residual migration velocity analysis in the plane wave domain theory and applications /

Jiao, Junru, January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

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