1. School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, P.R.C; School of Mechanical Engineering, Zhengzhou University, Zhengzhou 450001, P.R.C.
2. School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, P.R.C.
3. Department of Civil Engineering, University of Akron, Akron, OH 44325-3905