1. Institute of Systems Engineering, Macau University of Science and Technology, Taipa, Macau 999078, China
2. College of Computer and Communication Engineering, Liaoning Petrochemical University, Fushun 113001, China
3. Computer Science and Technology, Shandong University of Science and Technology, Qingdao 266590, China
4. Hitachi Building Technology (Guangzhou) Co., Ltd., Guangzhou 510670, China