1. College of Mathematics and Computer Science, Zhejiang Normal University, Jinhua, Zhejiang, China
2. School of Information Engineering, Jiangxi University of Science and Technology, Ganzhou, Jiangxi, China
3. Xi’an Research Institute of High Technology, Xi’an, Shanxi, China
4. College of Physics and Information Engineering, Fuzhou University, Fuzhou, Fujian, China