Acknowledgments

First and foremost, I would like to thank my supervisor and mentor, Associate Professor Dr. Georgy Gimel'farb, for his guidance, support and patience throughout my PhD study. I do appreciate his efforts and encouragement, numerous discussions and valuable feedback in the last four years.

I would also like to thank all the staff and fellow students in the Department of Computer Science, the University of Auckland, who have contributed to my research, for their help, input and motivation during the last few years.

Thanks must go to my wife Lihang and my family for their unconditional and loving support.

This work was financially supported by the Royal Society of New Zealand under Marsden Fund Grant UOA122 and by the Bright Future Top Achiever Doctoral Scholarship of the Tertiary Education Commission of New Zealand.