Funding for this research was provided by:
Ministry of Education, Culture, Sports, Science and Technology (KAKENHI Grant Number 26109007, Earthquake, Volcano Hazards Observation, Research Program)
Japan Society for the Promotion of Science (KAKENHI Grant Number 19K04038)
Article History
Received: 6 January 2020
Accepted: 19 May 2020
First Online: 1 June 2020
Ethics approval and consent to participate
: Not applicable.
: Not applicable.
: The authors do not have competing interests.