1. College of Computer Science and Technology, Jilin University, Changchun 130012, China
2. Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education, Jilin University, Changchun 130012, China
3. College of Software, Nanchang Hangkong University, Nanchang 330063, China
4. College of Physics and Electronic Information, Wenzhou University, Zhejiang 325035, China