1. School of automation, Liaocheng University, Beijing, China, 100081 (e-mail: Chenguoliang3936@126.com)
2. The University of Hong Kong, University of Hong Kong, Hong Kong, China, 999077 (e-mail: fancc@connect.hku.hk)
3. School of Automation, Beijing Institute of Technology, Beijing, China, 100081 (e-mail: sunjian@bit.edu.cn)
4. The school of Mathematics science, Liaocheng University, Liaocheng, China, 252000 (e-mail: njustxjw@126.com)