1. School of Automobile and Traffic Engineering, Hefei University of Technology, Hefei, Anhui, P. R. China
2. School of Civil and Hydraulic Engineering, Hefei University of Technology, Hefei, Anhui, P. R. China
3. School of Automobile, Chang’an University, Xi’an, Shaanxi, P. R. China
4. School of Mechanical and Electrical Engineering, Anhui Jianzhu University, Hefei, Anhui, P. R. China