1. College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China
2. Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore
3. Department of Chemical Engineering, Faculty of Engineering Science, University College London, London WC1E 6BT, UK
4. Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment, Hunan University of Science and Technology, Xiangtan 411201, China