1. Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
2. Beijing Key Laboratory of Computational Intelligence and Intelligent System, Beijing University of Technology, Beijing 100124, China
3. Engineering Research Center of Digital Community, Beijing University of Technology, Beijing 100124, China
4. Guixi Smelter, Jiangxi Copper Corporation Limited, Guixi, Jiangxi 335400, China
5. Beijing RTlink Technology Co. Ltd., Beijing 100024, China