1. State Key Laboratory of Coal Resources and Safe Mining, School of Mines, China University of Mining and Technology, Xuzhou 221116, China
2. National Energy Group Ningxia Coal Industry Co., Ltd., Yinchuan 750000, China
3. Xinjiang Institute of Engineering, Urumqi, Xinjiang 830023, China
4. Shandong Energy Xinwen Mining Group Co., Ltd., Xintai, Shandong 271200, China
5. Binxian Shuiliandong Coal Mine Co., Ltd., Binzhou, Shanxi 713500, China