1. Ph.D. Candidate, MIRARCO–Mining Innovation, Laurentian Univ., Sudbury, Canada P3E 2C6; School of Resources and Safety Engineering, Central South Univ., #932 Lushan South Rd., Changsha 410083, China.
2. Professor, School of Resources and Safety Engineering, Central South Univ., #932 Lushan South Rd., Changsha 410083, China.
3. Assistant Professor, School of Resources and Safety Engineering, Central South Univ., #932 Lushan South Rd., Changsha 410083, China; State Key Laboratory of Safety and Health for Metal Mines, #666 Xitang Rd., Maanshan 243000, China (corresponding author).