1. Faculty of Information Technology, Macau University of Science and Technology, Taipa, Macau
2. Department of Computing, The Hong Kong Polytechnic University, Hung Hom, Hong Kong
3. School of Software, Tsinghua University, Beijing, People's Republic of China
4. College of Intelligence and Computing, Tianjin University, Tianjin, People's Republic of China
5. Information Science and Technology Center, Kobe University, Kobe, Japan