1. School of Computer Science and Technology, Heilongjiang University, Harbin 150080, China
2. Department of Computer Science and Information Technology, La Trobe University, Melbourne 3083, Australia
3. School of Mathematical Science, Heilongjiang University, Harbin 150080, China
4. School of Electrical and Information Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
5. Center for Frontier Medical Engineering, Chiba University, Chiba 2638522, Japan