1. School of Telecommunications Engineering, Xidian University, Xi'an, China
2. School of Computer Science and Engineering, Central South University, Changsha, China
3. Department of Computing, Hong Kong Polytechnic University, Hongkong, China
4. Department of Computer and Network Engineering, The University of Electro-Communications, Chofugaoka, Japan
5. Department of Electrical Engineering, Qassim University, Buraydah, Saudi Arabia
6. Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Canada