First and foremost, I would like to thank my supervisor, Assoc. Prof. Ng Wee Keong, for his kindness, trust, and patience throughout the years of my PhD study. The research guidance given by Prof. Ng has important influence to the success of our new discovery. The research environment in NTU SCSE provides us the research freedom to carry out meaningful explorations and experimentations with new inventions or innovations. The regular seminars held by the school and university inspires us with new ideas and expand our core research to stay up-todate and relevant. I would like to thank Assoc. Prof. Adams Kong Wai Kin, Assoc.