1. School of Information Science and Technology, Donghua University, Shanghai 200051, China
2. Department of Computer Science, Brunel University, Uxbridge, Middlesex UB8 3PH, UK
3. Communication Systems and Networks (CSN) Research Group, Faculty of Engineering, King Abdulaziz University, Jeddah 21589, Saudi Arabia
4. Research Institute of Intelligent Control and Systems, Harbin Institute of Technology, Harbin 150001, China
5. Department of Applied Mathematics, Harbin University of Science and Technology, Harbin 150080, China
6. Department of Mathematics, Southeast University, Nanjing 210096, China