Acknowledgement

It has been an exceptional journey - one that I had never dreamed of. My research career was started not long after I became an MIS undergraduate student in 1989, when I attended Dr. Hsinchun Chen's first class at The University of Arizona. I am deeply indebted to Dr. Chen for his encouragement, advice, mentoring, and research support throughout my undergraduate, master's, and doctoral studies. I also truly appreciate his patience and tolerance during my numerous mishaps. This dissertation is part of the research carried out through his vision throughout last ten years.

I am fortunate to have the opportunity to work with a group of energetic people in Dr. Chen's AI Lab. I have enjoyed every moment that we have worked together including all those late night lab activities. All former and present AI Lab members have taught me many things about life. I appreciate all their friendships and their collective encouragement to finish this dissertation. I want especially to thank Chienting Lin, Thian-Huat Ong, Marshall Ramsey, Yohanes Santoso, Harry Li, Samuel Yim, and Chris Schuffels for sharing their technical wisdom, and to thank Andrea Houston, Joanne Martinez, Kris Tolle, and Rosie Hauck for sharing their research ideas.

Finally, it is impossible to have my research career without my parents' love and support, as well as my family and friends' encouragement. This dissertation is dedicated to them.

To all of you, thank you.