1. Hunan Key Laboratory for Computation and Simulation in Science and Engineering, Key Laboratory of Intelligent Computing and Information Processing of Ministry of Education, School of Mathematics and Computational Science, Xiangtan University, Xiangtan, Hunan 411105, China
2. School of Mathematics and Statistics, Wuhan University, Wuhan 430072, China
3. School of Mathematical Sciences, Peking University, Beijing 100871, China
4. Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada