1. National Center for International Joint Research of Electronic Materials and Systems, School of Electrical and Information Engineering, Zhengzhou University,International Joint-Laboratory of Electronic Materials and Systems of Henan Province,Zhengzhou,Henan,P. R. China,450001
2. School of Mathematics and Statistics, Zhengzhou University,Zhengzhou,Henan,P. R. China,450001
3. School of Electrical and Information Engineering, North Minzu University,Yinchuan,Ningxia,P. R. China,750001