ACKNOWLEDGMENTS


 This work would not have been possible without the

teachings, the constant guidance, and the expert advice I received from my advisor, Professor Keith L. Doty. I am

especially grateful for his encouragements, his enthusiasm,

his great sense of humor, and his friendliness which made this work so enjoyable.

 I would like to thank Dr. Herman Lam, Dr. Gerhard X. Ritter, Dr. Ralph G. Selfridge, and Dr. Jose C. Principe for their excellent service on my final committee. Thanks are also due to Dr. Giuseppe Basile and Dr. Eginhard J. Muth for their previous service on my committee.

 I also wish to express my appreciation to Dr. Carl D. Crane III, for his help with the computer graphics simulations and the photographs of Figure 9.4 of this text,

and to Dr. Joseph Duffy for taking the time to answer my questions.

 The financial support I received, throughout my

doctoral studies, from the Mathematics Department and from the Electrical Engineering Department of the University of Florida, in the form of teaching assistantships, is gracefully acknowleged. Special thanks are due to


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