1. School of Information and Electrical Engineering, Ludong University, Yantai 264025, China
2. Tianjin Key Laboratory of Microgravity and Hypogravity Environment Simulation Technology, Tianjin 300000, China
3. School of Mathematics and Statistics Science, Ludong University, Yantai 264025, China
4. Ulsan Ship and Ocean College, Ludong University, Yantai 264025, China