1. College of Mechanical & Electrical Engineering, Inner Mongolia Agricultural University, Hohhot, P. R. China
2. State Key Laboratory of Smart Manufacturing for Special Vehicles and Transmission System, Baotou, Inner Mongolia, P. R. China
3. Inner Mongolia Key Laboratory of Intelligent Diagnosis and Control of Mechatronic Systems, Inner Mongolia University of Science & Technology, Baotou, Inner Mongolia, P. R. China
4. Theory of Lubrication and Bearing Institute, Key Laboratory of Education Ministry for Modern Design & Rotor-Bearing Systems, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China