ACKNOWLEDGMENTS

I would like to express my sincere appreciation to my advisors, Dr. Glenn S. Daehn and Dr. Robert H. Wagoner, for their kind help, guidance, support and encouragement throughout my study. I would also like to thank Dr. John J. Lannutti for providing technical advice, conducting CT tests and being a member of the dissertation and candidacy exam committee. I would like to thank Ms. Yuehong Fu and Ms. Weidong Wu for kindly cooperation on both experiments and simulation. Ms. Chris Putnam is greatly acknowledged for her proofreading assistance and daily support to the research group. Also I would like to thank Lloyd Barnhart, Cameron Begg, Henk Colijn, Steve Bright, Ken Kushner and Gary Dodge for their help with experimental testing.

I would like to express thanks for the financial support of The National Science Foundation (grant No. DMR-970558).

And, I would like to thank my wife for her unbelievable support and understanding through my entire project.