1. School of Mechanical Engineering and Automation, Northeastern University, Shenyang, P R China
2. China North Vehicle Research Institute, Beijing, P R China
3. School of Mechanical Engineering and Automation, Dalian Polytechnic University, Dalian, P R China
4. Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education, Northeastern University, Shenyang, P R China