School of Computer Science and Engineering, Central South University, Changsha, China.|School of Computer Science and Engineering, Central South University, Changsha, China.|School of Computing, Clemson University, Clemson, SC, USA.|Division of Biomedical Engineering and Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SKS7N5A9, Canada.|School of Computer Science and Engineering, Central South University, Changsha, China.