1. School of Computer Science and Technology, Dalian University of Technology, Dalian 116024, China
2. Key Laboratory of Advanced Design and Intelligent Computing, Ministry of Education, School of Software Engineering, Dalian University, Dalian 116622, China
3. Knowledge Engineering and Discovery Research Institute, Auckland University of Technology, Auckland 1010, New Zealand
4. Intelligent Systems Research Center, Ulster University, Londonderry BT48, United Kingdom
5. IICT, Bulgarian Academy of Sciences, Sofia 1040, Bulgaria