1. College of Mechanical Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China e-mail:
2. College of Mechanical Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; School of Mechanical Engineering, Anhui University of Technology, Ma'anshan 243000, China e-mail: