Affiliation: | 1. College of Science, Hohai University, Nanjing, People's Republic of China;2. School of Statistics and Mathematics, Nanjing Audit University, Nanjing, People's Republic of China;3. College of Science, Nanjing University of Posts and Telecommunications, Nanjing, People's Republic of China;4. College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, People's Republic of China |