1. School of Computer Science and Engineering (and the GuangDong Province Key Laboratory of Information Security Technology), Sun Yat-sen University, Guangzhou, P.R. China
2. Dept. of Electrical and Computer Engineering, St Cloud State University, St Cloud, USA
3. School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou, P.R. China
4. School of Engineering and Information Technology, University of New South Wales at the Australian Defence Force Academy, Canberra, Australia