1. School of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an, Shaanxi 710054, P. R. China
2. Shaanxi Key Laboratory of Prevention and Control of Coal Fire, Xi’an University of Science and Technology, Xi’an, Shaanxi 710054, P. R. China
3. Department of Safety, Health, and Environmental Engineering, National Yunlin University of Science and Technology, Yunlin 64002, Taiwan, Republic of China