Accepted

^ ' A I would like to take this opportimity to extend my thanks to the members of n my committee for their guidance and invaluable advice. I am deeply indebted to my chairperson. Professor Paul Randolph, for his support and encouragement throughout my entire doctoral program. Without his leadership the realization of this research would have been impossible. I am greatly indebted to Professor James Bums, Professor Surya Yadav, and Professor Surya Liman for their help, support, constmctive suggestions and invaluable comments. I would like to thank numerous other persons who were helpful for their critique and helpfiil ideas. My special thanks go to Abdul Qureshi for providing unlimited help throughout the development phase of the prototype. In the end, I wish to express my heartfelt appreciation to my wife, Hina, to my parents, and to my sister and brother. Without their patience and prayers this research would not have been completed