1. School of Automation, Nanjing University of Science and Technology, 12436 Nanjing, Jiangsu, China, 210094 (e-mail: fengli4131@gmail.com)
2. School of Computing, Engineering and Mathematics, University of Western Sydney, Sydney, New South Wales, Australia, 2751 (e-mail: w.zheng@westernsydney.edu.au)
3. School of Automation, Nanjing University of Science and Technology, Nanjing, Jiangsu, China, 210094 (e-mail: syxu@njust.edu.cn)