1. Professor, School of Astronautics, Beijing Univ. of Aeronautics and Astronautics, Beijing 100191, China (corresponding author). E-mail address:
2. Ph.D. Candidate, School of Astronautics, Beijing Univ. of Aeronautics and Astronautics, Beijing 100191, China.
3. Professor, School of Astronautics, Beijing Univ. of Aeronautics and Astronautics, Beijing 100191, China.
4. Associate Professor, School of Astronautics, Beijing Univ. of Aeronautics and Astronautics, Beijing 100191, China.