1. Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Coal Mines, Hunan University of Science and Technology, Xiangtan, 411201 Hunan Province, China
2. Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines, Hunan University of Science and Technology, Xiangtan, 411201 Hunan Province, China
3. School of Resource Environment and Safety Engineering, Hunan University of Science and Technology, Xiangtan, 411201 Hunan Province, China