1. State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong Univ. of Science and Technology, Qingdao, Shandong, 266590, CN
2. State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong Univ. of Science and Technology, Qingdao, Shandong, 266590, CN (Corresponding author), e-mail: xuesheng1134@163.com