Combinatorial designs and codes related to information-communication

Acknowledgments When I came to Japan, I never dared to imagine that I would pursue a PhD at Nagoya University. Without my supervisor, I might not have completed the long journey of my PhD studies. So, first and foremost, I would like to thank my supervisor, Professor Masakazu Jimbo, Nagoya University, for his kind supervision and encouragement, not only in my studies but also in my private life. He has provided an environment full of possibilities and encouraged me to seek the opportunities. I am most grateful to him for bringing me to the world of combinatorial mathematics and letting me have a chance to solve so many problems. I was able to complete this thesis because of his patience, excellent guidance and advice. I am also very grateful to Professor Miwako Mishima of Gifu University. She is really kind and caring. She always patiently helped me with the insufficient part of my papers. I thank her for teaching me how to write a fluent and professional paper. I would like to thank both of them for encouraging me to and supporting me in, not only attending meetings and conferences, but also taking part in the preparatory group for international conferences. These were all very good opportunities for me to practice presentation skills and to develop communication and coordination. I would like to thank Professor Junya Satoh, who is a member of my thesis committee. He taught me a lot about number theory. He also helped to review my papers and offered valuable comments. Without him, my research could not be so complete and productive. I express my warm thanks I met at conferences. My communication skills and thinking skills were improved because of your unselfish teaching. Also, I would like to thank all our laboratory members. The time we studied in the laboratory will be an unforgettable memory in my life. Finally, I wish to express my gratitude to my family and my friends for their support, especially my husband, Lipu, who spent many sleepless nights with me and was always my best listener. It would have been impossible to complete my doctoral studies without their hearty encouragement.