1. School of Marine Electrical Engineering, Dalian Maritime University, Dalian, China
2. Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education and the Institute of Advanced Control Technology, Dalian University of Technology, Dalian, China
3. School of Information and Control Engineering, Qingdao University of Technology, Qingdao, China
4. Department of Automation, Tsinghua University, Beijing, China