1. Institute of System Engineering, Faculty of Science, Jiangsu University, 301 Xuefu, Zhenjiang 212013, China
2. Department of Computer Science, Faculty of Applied Science, Kumasi Polytechnic, P.O. Box 854, Kumasi, Ghana
3. College of Finance and Economics, Jiangsu University, 301 Xuefu, Zhenjiang 212013, China
4. Computer Science and Technology, School of Computer Science and Telecommunication, Jiangsu University, 301 Xuefu, Zhenjiang 212013, China