1. DUT-RU International School of Information Science & Engineering, Dalian University of Technology, Dalian, China
2. College of Computer Science and Technology, Zhejiang University of Technology, Hangzhou, China
3. Department of Mathematics, The University of Hong Kong, Hong Kang, China
4. Department of Mathematics and Statistics, University of Victoria, Victoria, BC, Canada
5. Department of Mathematics, SUSTech International Center for Mathematics, National Center for Applied Mathematics Shenzhen, Southern University of Science and Technology, Shenzhen, Guangdong, China