Institution: | 1. School of Mathematics and Statistics, Xidian University, Xi’an, Shaanxi, China;2. Center of Mathematical Sciences, Huazhong University of Science and Technology, Wuhan, Hubei, China;1. School of Computer Science, Southwest Petroleum University, Chengdu 610500, China;2. School of Public Health and Management, Chongqing Medical University, Chongqing 400016, China |