1. Department of Mechanical Engineering, Clemson University, Clemson, South Carolina 29634-0921, USA
2. School of Instrument Science and Opto-Electronic Engineering, Hefei University of Technology, Hefei 230009, China
3. Department of Mechanical Engineering, University of West Florida, Pensacola, Florida 32514, USA
4. College of Controlling Science and Engineering, China University of Petroleum, Qingdao 257061, China