1. School of Computer Science and Engineering, Nanjing University of Science and Technology, Nanjing, China
2. Research Institute of Big Knowledge, Hefei University of Technology, Hefei, China
3. School of Information Engineering, Nanjing Audit University, Nanjing, China
4. School of Computing, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
5. Jiangsu Provincial Key Laboratory of E-Business, Nanjing University of Finance and Economics, Nanjing, China