1. Professor, School of Resources and Safety Engineering, Central South Univ., Changsha, Hunan 410083, China.
2. State Key Laboratory of Coal Mine Disaster Dynamics and Control, College of Resources and Safety Engineering, Chongqing Univ., Chongqing 400044, China.
3. Associate Professor, State Key Laboratory of Coal Mine Disaster Dynamics and Control, College of Resources and Safety Engineering, Chongqing Univ., Chongqing 400044, China (corresponding author).