Yap Kim Hui, for his nurturing, encouragement and continuous support during my research. Secondly, I wish to express my sincere thanks towards Miao Zhenwei and Zhang Dajiang for their help. I am also grateful towards all the team members in the ROSE lab, for their help, collaborations, and friendship. Finally, I am deeply indebted to my family for their love and endless support. Without them, I would never have chance and courage to pursue a degree in Master of Engineering.