1. College of Management, Shenzhen University, Shenzhen 518061, China
2. School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China
3. State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China
4. School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China