1. College of Electrical Engineering Weihai Innovation Research Institute Qingdao University Qingdao 266071 China
2. State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical Engineering China University of Petroleum (East China) Qingdao 266580 China
3. Xi'an Traffic Engineering Institute Xi'an 710300 China
4. Qingdao Haier Washing Machine Co., Ltd Qingdao 26000 China
5. School of Information Engineering Zhejiang University of Technology Hangzhou 310023 China