Long Li
Department of Mathematics and Computational Science, Hengyang Normal University, Hengyang, 421008, China
Tian Xu
Department of Mathematics and Computational Science, Hengyang Normal University, Hengyang, 421008, China
Yan Liu
Department of Applied Mathematics, Dalian Polytechnic University, Dalian, 116034, China
Jie Yang
School of Mathematical Sciences, Dalian University of Technology, Dalian, 116024, China