First and foremost I would like to express my deepest appreciation to my Director of Studies, Dr. Martin D. Beer. It has been a pleasure to work under his supervision for the past 4 years. His advices, enthusiasm, encouragement and dedication have truly been aspirations. I would like also to thank my second supervisor Dr. Paul Crowther for his support and valuable comments in completing my research work. Without their guidance and persistent help, this thesis would not have been possible. I would like to express my gratitude to Majlis Amanah Rakyat of Malaysia for the financial support. I also would like to thank my friends in Unit 12, members of Cultural, Communication and Computing Research Institute, Sheffield Hallam University and Dr. Frances Slack for their assistance during my entire study period. Thank you to my supportive wife, Anees Abdul Aziz and my two little children, Aiesyah and Aadam. Although this journey is quite challenging, their understanding, patient and continuous support have motivated me to complete this PhD. Last but not least, I would like to thank my parents for all their moral support and prayer. Without them, I would not have been successful.