[1] North Univ China, Sch Mech Engn, Taiyuan 030051, Shanxi, Peoples R China
[2] JinZhong Univ, Sch Mech Engn, Jinzhong 030619, Shanxi, Peoples R China
[3] Shanxi Univ, Sch Automat & Software, Taiyuan 030006, Shanxi, Peoples R China
[4] Xi An Jiao Tong Univ, Key Lab, Educ Minist Modern Design & Rotor Bearing Syst, Xian 710049, Shaanxi, Peoples R China
[5] North Univ China, Taiyuan, Peoples R China