1. Key Laboratory of Knowledge Engineering with Big Data, Ministry of Education, and the School of Computer Science and Information Engineering, Hefei University of Technology (HFUT), Hefei, China
2. School of Computer Science and Information Engineering, Hefei University of Technology (HFUT), Hefei, China
3. Gansu Provincial Key Laboratory of Wearable Computing, School of Information Science and Engineering, Lanzhou University, Lanzhou, Gansu, China