I would like to express my sincere thanks to teachers, Assoc. Prof. Dr. Boonsiri Anantaset for her invaluable help and constant support throughout the course of this report. I am most grateful for her teaching and advice. I would not have achieved this report would not have been completed without all the support that I have always received from her.
Finally, I most gratefully acknowledge my parents and my friends for all their support throughout the period of this report