1. College of Electronic and Information Engineering, Southwest University, Chongqing 400715, China
2. Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing, College of Electronic and Information Engineering, Southwest University, Chongqing 400715, China
3. Training and Basic Education Management Office, Southwest University, Chongqing 400715, China
4. School of Computing and Information Science, Faculty of Science and Engineering, Anglia Ruskin University, Cambridge, United Kingdom