1. Department of Electrical Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong
2. School of Engineering, RMIT University, Melbourne, VIC, Australia
3. Department of Engineering, Nottingham Trent University, Nottingham, U.K.
4. School of Automation Engineering, Nanfang College, Guangzhou, China
5. Department of Electrical and Electronic Engineering, Tokushima University, Tokushima, Japan