As my four years of doctoral studies end, I will leave the campus and start my career. At this moment, I have mixed feelings. This last period of my life on campus is very precious to me. I would like to express my sincere appreciation to those who helped me during the four years of my Ph.D.  study at the University of Macau.

First and foremost, I am highly grateful to supervisor Dr. Li Haifeng and co-supervisor Dr. Ouyang Defang for their invaluable advice, continuous support, and patience during my Ph.D. study. Their immense knowledge and great experience have encouraged me throughout my academic research and daily life.

My sincere thanks also go to Dr. Hua Yu for his kind suggestions and assistants during my Ph.D. study. Thanks to all lab technicians for their hard work to keep a good lab environment.

A special appreciation goes to Dr. Dong Jie, Mr. Ye Zhuyifan and Mr. Zhang Yunsen for providing me the technical support in machine learning for my research.

Additional thanks go to Mr. Li Junjun, Ms. Lu Tianshu, Ms. Deng Jiayin, Ms. Wu Yiyang, Mr. Niu Liyuan, Ms. Wu Si and Mr. Zhu Yinghao for their warm-heart friendship and help.

I would like to express my sincere thanks to my parents and husband for their continued encouragement, emotional support and endless love. I could not have completed my Ph.D. research without their understanding, continued patience and unlimited support.