1. School of Information Technology, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, P. R. China
2. Department of Computer Science, Jiangsu Ocean University, Lianyungang 222000, Jinagsu, P. R. China
3. Department of Neurology, General Hospital of Ningxia Medical University, Yinchuan 750004, Ningxia, P. R. China