1. State Key Laboratory of Coal Resources and Safety Mining, China University of Mining and Technology, Xuzhou, China
2. Ministry of Education, Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining and Technology), Xuzhou, China
3. School of Safety Engineering, China University of Mining and Technology, Xuzhou, China
4. School of Mine Safety, North China Institute of Science and Technology, Sanhe, Hebei, China