1. College of Electronic and Information Engineering, Southwest University, Chongqing 400715, China
2. Training and Basic Education Management Office, Southwest University, Chongqing 400715, China
3. Key Laboratory of Cyber-Physical Fusion Intelligent Computing (South-Central Minzu University), State Ethnic Affairs Commission, Wuhan 430074, China
4. School of Computing and Information Science, Faculty of Science and Engineering, Anglia Ruskin University, Cambridge CB1 1PT, UK