1. Norman B. Keevil Institute of Mining Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
2. WA School of Mines: Minerals, Energy and Chemical Engineering, Bentley, WA 6102, Australia
3. Faculty of Science, University of the Fraser Valley, Abbotsford, BC V2S 7M8, Canada
4. School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
5. Key Laboratory of Efficient Mining and Safety of Metal Mines, Ministry of Education, University of Science and Technology Beijing, Beijing 100083, China