1. Nanjing University of Science and Technology, School of Computer Science and Engineering, No. 200 Xiaolingwei, Nanjing 210094, ChinabNanjing Branch of China Telecom Corp, No. 8 Lanqijie, Nanjing 210007, China
2. Nanjing University of Science and Technology, School of Computer Science and Engineering, No. 200 Xiaolingwei, Nanjing 210094, China
3. Nanjing University of Information Science and Technology, School of Computer and Software, No. 219, Ningliu Road, Nanjing 210044, China