1. Hunan University of Science and Technology,The School of Computer Science and Engineering,Xiangtan,P. R. China
2. Guangdong Key Laboratory of Information Security Technology,Hunan University of Science and Technology The State Key Laboratory of Information Security Institute of Information Engineering, Chinese Academy of Sciences Zhengzhou Xinda Institute of Advanced Technology
3. Changsha University of Science and Technology,The School of Computer and Communication Engineering,Changsha,P. R. China