1. College of Electrical and Information Engineering, Hunan University, Changsha, China
2. School of Robotics, Hunan University, Changsha, China
3. Inter-Disciplinary Research Center of Language Intelligence and Cultural Heritages, Hunan University, Changsha, China
4. College of Mechanical and Vehicle Engineering, Hunan University, Changsha, China
5. School of Automation, China University of Geosciences (Wuhan), Wuhan, China