Note: Funding Information: This study was partly supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan, under the Earthquake and Volcano Hazards Observation and Research Program, and KAKENHI Grant Numbers 26109001–26109007, and 15K21755. Funding Information: We express our sincere gratitude to the authors who contributed to this special issue and the reviewers who evaluated the contributions and gave thoughtful comments and suggestions. We also thank Editor-in-Chief Yasuo Ogawa and Vice Editor-in-Chief Masato Furuya for waiting patiently for our slow editing process.