1. School of Mechanical and Automotive Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, P.R. China
2. School of Mechanical Engineering, Shandong University, Jinan, P.R. China
3. Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE/Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan, P.R. China