Player Dominance Adjustment in GamesAbove all, I would like to thank my research supervisor, Prof. Ruck Thawonmas, who has supported me in all my endeavors and provided guidance, encouragement, and suggestion, gave me such many chances to publish papers in conferences organized in domestic or oversea. I appreciate his kindness to give his time generously. Besides, he has provided many useful materials as well as created an environment for me where it is a pleasure to study and conduct research.I would like to express special thanks to Dr. Pujana Paliyawan, who is like my second supervisor. I started my undergraduate research in advance with him and learned a lot of things necessary for writing papers, conducting experiments, polishing ideas for research, etc.. They helped me in all of my research studies, the paper would not be finished perfectly without their advice. I truly appreciate their time and kindness.Thanks also to my girlfriend Chen, for providing me consistent encouragement and caring within four years of undergraduate study, not only accompanies me in those wonderful lives, but also provides guidance for me in daily life even my research when required. Her existence keeping me optimistic when facing all the obstacles in my study and life in Japan.Most importantly, I would also like to thank my parents for their love, support, and encouragement.Finally, Thanks to Ritsumeikan University and all the professors as well as lecturers who taught me in classes. I would never forget valuable experiences gained there for the instructions they gave.