I would like to thank my supervisor, Dr Lim Meng Hiot, for his supervision and guidance, specially the patience to me. In addition to his concern about my research work, I am very grateful for his cares on my life. His style of supervision and the way of communication will definitely affect my future. I would also like to thank Dr Ong Yew Soon for his help and guidance, acting as a good friend and co-supervisor of me. I also want to express my appreciation to Dr Ponnuthurai Nagaratnam Suganthan for his friendly assistance and guidance. Most importantly, special thanks go to my family, especially my wife, thanks for their understanding and support. I also like to thank Mdm. Noraidillah Bte Mohamed Ali from Intelligent System Centre for her continuous kindly help.