First of all, thanks to Almighty Allah for granting me the courage, knowledge, determination and environment to continue my research work. I also pay all the tributes to the Prophet Muhammad (Peace be Upon Him), for enlightening our conscience, who’s love is the real success of life.
I am especially thankful to my mother and my spouse for their continuous support, encouragement and patience during my doctoral studies. I am very grateful to my supervisor Dr. Aamer Iqbal Bhatti and co-supervisor Dr. Muddassar Abbas Rizvi for all their support, guidance and discussions in finding the right research direction. I owe thanks to my supervisor Dr. Aamer Iqbal Bhatti for his scholarly guidance, encouragement and valuable suggestions that enable me to follow the right track during my research work. I am indebted to Dr.
Muddassar for his attention, guidance and encouragement in the present work. He was always available for discussion and help on different issues faced during this work. It is his consistent scholarly guidance that made successful completion of this work possible. I am thankful to Dr. Kamran Iqbal and Dr.
Noureddine Manamanni who spared their precious time to review this research work and provided the valuable comments for its improvement. I am also thankful to all members of CASPR for their valuable suggestions and support. It is really a blessing to have company of so supporting and competent people around me who helped me out of problems I faced in this research work. I am also thankful to my colleague and friend Dr.
Faisal Nadeem for his help in the proofreading of this thesis. Special thanks are due to my parent organization PINSTECH for facilitating my studies with study leave and to HEC for funding my doctoral studies at this institute