1. College of Engineering, Huaqiao University, Quanzhou, China
2. Department of Computer and Electronics Systems Engineering, Hankuk University of Foreign Studies, Yongin-si, South Korea
3. School of Computer and Software, Nanjing University of Information Science and Technology, Nanjing, China
4. College of Computer Science and Technology, China University of Petroleum (East China), Qingdao, China