1. College of Electronic Science and Technology, National University of Defense Technology (NUDT), Changsha, Hunan, China
2. College of Systems Engineering, National University of Defense Technology (NUDT), Changsha, Hunan, China
3. College of Liberal Arts and Sciences, National University of Defense Technology (NUDT), Changsha, Hunan, China
4. College of Intelligence Science and Technology, National University of Defense Technology (NUDT), Changsha, Hunan, China
5. Center for Machine Vision and Signal Analysis, Oulu University, Oulu, Finland