Dedication

This dissertation is dedicated to my parents, Sang Wook Kim and Chang Hee Kim, for their unconditional sacrifice, endless support, and love. Acknowledgements Pursuing my doctoral degree at Carnegie Mellon has been a challenging yet rewarding experience of my life. All I had was luck, the best of which was in the form of my advisor, Professor Tridas Mukhopadhyay who is not only my academic advisor, but also my mentor. He has helped me go through all the difficulties I came across for the past five years at Carnegie Mellon. I would like to sincerely thank him for his continuous guidance and support throughout my doctoral program. He has spent countless hours discussing my research, sharing his insights and experiences with me, guiding me through tough times, and sharpening my learning skills. Without his support, patience, and confidence in me, this dissertation would not be possible. I feel honored to have had a chance to work with him and learn from him. I am grateful for the contributions of Professor Pei-yu Chen who has always encouraged me with belief in me since my first day at Carnegie Mellon. She has helped me develop analytical skills as well as research ideas. I have benefited from every single interaction with her. She ha