1. Department of Engineering Physics, Tsinghua University, Beijing 100084, China
2. Institute of Public Safety Research, Tsinghua University, Beijing 100084, China
3. School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
4. School of National Safety and Emergency Management, Beijing Normal University at Zhuhai, Zhuhai 519087, China
5. Academy of Disaster Reduction and Emergency Management, Ministry of Emergency Management & Ministry of Education, Beijing Normal University, Beijing 100875, China