1. College of Mechanical Engineering & Beijing Key Laboratory of Measurement and Control of Mechanical and Electrical System, Beijing Information Science and Technology University, Beijing, P. R. China
2. Department of Mechanics, Guangxi University, Nanning, P. R. China
3. Department of Mechanics, Inner Mongolia University of Technology, Hohhot, P. R. China
4. School of Aeronautics and Astronautics, Tiangong University, Tianjin, P. R. China