1. College of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing, China
2. College of Information and Communication Engineering, Harbin Engineering University, Harbin, China
3. Faculty of Electrical Engineering and Information Technology, RWTH Aachen University, Aachen, Germany
4. International Research Institute of Disaster Science (IRIDeS), Tohoku University, Sendai, Japan