1. Department of Mathematics, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China
2. Key Laboratory of Mathematical Modelling and High Performance Computing of Air Vehicles (NUAA), MIIT, Nanjing, People's Republic of China
3. College of Mathematics and Statistics, Nanjing University of Information Science and Technology, Nanjing, People's Republic of China