No description available.

Typescript, etc.

by Tan Wai Pin. / Thesis (M.Phil)--Chinese University of Hong Kong, 1993. / Includes bibliographical references. / DEDICATION --- p.ii / ABSTRACT --- p.iii / ACKNOWLEDGMENTS --- p.ix / Chapter CHAPTER 1 --- p.10 / Chapter 1 --- INTRODUCTIONS --- p.10 / Chapter 2. --- REFERENCE --- p.15 / Chapter CHAPTER 2 --- COMPUTATION OF CYLINDER FUNCTIONS --- p.17 / Chapter 1. --- INTRODUCTION --- p.17 / Chapter 2. --- NEED OF COMPUTING CYLINDER FUNCTION OF COMPLEX ARGUMENTS --- p.18 / Chapter 3. --- NEED OF COMPUTING HANKEL FUNCTIONS --- p.19 / Chapter 4. --- OUTLINE OF APPROACH --- p.22 / Chapter 5. --- ALGORITHMS --- p.24 / Chapter 5.1. --- REGION 1: IM(Z) < 5 AND RE(Z)<16 : --- p.25 / Chapter 5.1.1. --- Computation of Jn(z) : --- p.25 / Chapter 5.1.2. --- Determination of Starting Index M: --- p.26 / Chapter 5.1.3. --- Determination of Normalization Constant : --- p.26 / Chapter 5.1.4. --- "Computation of Yn(z),Hn(1)(z) and Hn(2) (z)" --- p.29 / Chapter 5.2. --- REGION 2 : --- p.30 / Chapter 5.3. --- REGION 3 : --- p.32 / Chapter 5.3.1 --- Computation of Jn(z) : --- p.52 / Chapter 5.3.2 --- "Computation of Hn(1) (z),H(n2)(z) and Yn(z) :" --- p.40 / Chapter 5.3.3 --- Determination of Point of Starting Exponential Scaling : --- p.42 / Chapter 5.4. --- REGION 4 : --- p.42 / Chapter 5.5. --- REGION 5 : --- p.42 / Chapter 6. --- VERIFICATION --- p.43 / Chapter 7. --- REFERENCE --- p.46 / Chapter CHAPTER 3 --- INPUT IMPEDANCE OF CYLINDRICAL-RECTANGULAR MICROSTRIP ANTENNA --- p.48 / Chapter 1. --- INTRODUCTION --- p.48 / Chapter 2. --- FORMULATION --- p.49 / Chapter 3. --- DISCUSSION --- p.62 / Chapter 4. --- REFERENCES --- p.68 / Chapter CHAPTER 4 --- MUTUAL IMPEDANCE OF CYLINDRICAL-RECTANGULAR MICROSTRIP PATCH ANTENNAS --- p.70 / Chapter 1. --- INTRODUCTION --- p.70 / Chapter 2. --- FORMULATION --- p.70 / Chapter 3. --- DISCUSSION --- p.77 / Chapter 4. --- REFERENCES --- p.83 / Chapter CHAPTER 5 --- RESONANCE OF RECTANGULAR MICROSTRIP ANTENNA INSIDE A METALLIC CYLINDER --- p.84 / Chapter 1. --- INTRODUCTION --- p.84 / Chapter 2. --- FORMULATION --- p.85 / Chapter 3. --- NUMERICAL RESULTS --- p.96 / Chapter 4. --- CONCLUSION --- p.98 / Chapter 5. --- REFERENCES --- p.102 / Chapter CHAPTER 6 --- INPUT IMPEDANCE OF RECTANGULAR MICROSTRIP ANTENNA INSIDE A METALLIC CYLINDER --- p.104 / Chapter 1. --- INTRODUCTION --- p.104 / Chapter 2. --- FORMULATION --- p.104 / Chapter 3. --- NUMERICAL RESULTS --- p.106 / Chapter 4. --- CONCLUSION --- p.111 / Chapter 5. --- REFERENCES --- p.112 / Chapter CHAPTER 7 --- SUMMARY --- p.113 / APPENDIX A --- p.117 / APPENDIX B --- p.119 / PUBLICATION LIST : --- p.121

Boundary variation method and material distribution method are distinct approaches for structural optimization. In the early days, due to the fact that boundary variation methods were generally not able to handle topological changes, it was applied only in shape optimization problems where the topology of initial design is fixed during optimization process. To enable topological changes that are essential to deliver major performance improvements, material distribution method was introduced in the work of Bendsoe and Kikuchi, and thereafter widely adopted in nearly all aspects of topology optimization. Recently a novel boundary variation method for topology optimization was developed based on level set method, in which topological changes is allowed for. In the thesis, we study the level set based boundary variation method and material distribution method for structure optimization problem. / Finally, we studied the semi-Lagrange scheme to solve the Hamilton-Jacobi equation in level set based boundary variation method. In level set method, the free boundary of a structure is optimized via solution of a Hamilton-Jacobi equation. The numerical stability condition in explicit schemes for discrete Hamilton-Jacobi equation severely restricts the time step. To improve the numerical efficiency, we employ a semi-Lagrange scheme to solve Hamilton-Jacobi equation. Therefore, much larger time steps can be obtained and the number of iterations before convergence is greatly reduced. / Firstly, we studied the minimum compliance optimization problem of thermoelastic structures. In this optimization problem, we find that the optimal structures given by the state-of-art material distribution method, SIMP i method, generally have large area of intermediate density values that are not feasible in practical engineering applications because of their poor manufacturability and high costs. Therefore, we apply level set based boundary variation method in the optimization problem. As numerical results show, the optimal structures obtained are well suited to engineering applications. / To sum up, we explore in this thesis the boundary variation method and material distribution method for structure optimization problem. Several meaningful results and conclusions are obtained. / We secondly studied the stress minimization problem. In practical applications the most important requirement on a structure is often the strength of structure which characterizes the resistance to failure. In stress minimization problem, the objective is to minimize the distribution of von Mises stress in a structure. Here, level set method gives a significant convenience for stress optimization, in particular, we need not to incorporate any stress amplification factor of material microstructure which would be an important issue in material distribution method. Moreover, in order to derive more control of maximum stress, we utilize the Kreisselmeier-Steinhauser function to aggregate stresses at each point in a structure into a single global function. / Xia, Qi. / "October 2007." / Adviser: Michael Yu Wang. / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4993. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 102-111). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Typescript (Photocopy) Bibliography: leaf 75.

Thesis (Ph. D.)--Oregon State University, 1970. / Typescript (photocopy). Includes bibliographical references (leaves 90-91). Also available on the World Wide Web.

Thesis (Ph.D.)--Baylor University, 2005. / Includes bibliographical references (p. 54-58).

Thesis (M.A.)--University of North Carolina at Greensboro, 2006. / Title from PDF title page screen. Advisor: Maya Chhetri; submitted to the Dept. of Mathematical Sciences. Includes bibliographical references (p. 39-40).

Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, September 2003. / Thesis advisor(s): Peter C. Chu, Steve Haeger. Includes bibliographical references (p. 73-77). Also available online.

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.