1. School of Communication and Information Engineering, Chongqing University of Posts and Telecommunications, Chongqing, China
2. Advanced Robotics and Intelligent Systems Laboratory, School of Engineering, University of Guelph, Guelph, ON, Canada
3. Computer school, Hubei University of Arts and Science, Xiangyang, China
4. Future Technology Research Center, National Yunlin University of Science and Technology, Douliu City, Taiwan
5. Graduate School of Science and Engineering, Hosei University, Tokyo, Japan