1. School of Computer Science and Engineering, Northeastern Univ., Shenyang 110819, China; mailing address: No. 3-11, Wenhua Rd., Heping District, Shenyang 110819, China.
2. School of Information Science and Engineering, Northeastern Univ., Shenyang 110819, China; mailing address: No. 3-11, Wenhua Rd., Heping District, Shenyang 110819, China.
3. Professor, School of Information Science and Engineering, Northeastern Univ., Shenyang 110819, China; mailing address: No. 3-11, Wenhua Rd., Heping District, Shenyang 110819, China (corresponding author).
4. School of Automation, Shenyang Aerospace Univ., Shenyang 110136, China; mailing address: No. 37, Daoyi Southern St., Shenbei New District, Shenyang 110136, China.