1. School of Computer Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
2. Fujian Key Laboratory of Financial Information Processing, Putian University, Putian, China
3. Department of Telecommunication, Xidian University, Xi'an, China
4. Department of Computer and Network Engineering, The University of Electro-Communications, Chofugaoka, Japan
5. Department of Electronic and Computer Engineering, University of Waterloo, Waterloo, Canada