1. School of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, China
2. State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources, China University of Mining and Technology, Xuzhou 221116, China
3. Anhui Province Wanbei Coal-Electricity Group Co., Ltd., Suzhou 234000, China
4. Key Laboratory of In-Situ Property-Improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China