1. College of Computer Science & Technology, Zhejiang University of Technology, 288 Liuhe Rd, Hangzhou 310023, P. R. China
2. School of Communication Engineering, Hangzhou Dianzi University, 1158, No. 2 Avenue, Xiasha, Hangzhou 310018, P. R. China
3. Key Laboratory of Metallurgical Equipment and Control Technology of Ministry of Education, Institute of Precision Manufacturing, 947 Heping Avenue, Wuhan 430081, P. R. China
4. Intelligent Systems and Biomedical Robotics Group, School of Computing, University of Portsmouth, Portsmouth PO1 3HE, UK
5. School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China