system, some answered that the cloud system was useful for efficiently obtaining information for restoring lifelines, while others answered that cost is the problem for introducing systems. There were also needs for considering the use of information from residents via the internet. For communicating information for reconstruction, the necessity to utilize multiple media is pointed out. Furthermore, how to ensure accurate and prompt responses to the content of the information to be delivered is pointed out as a problem to be discussed.

## Section 3 The 2016 Kumamoto Earthquake and New Means of Sharing Disaster Information

At the time of the 2016 Kumamoto Earthquake, power supply was resumed soon and prior measures taken by carriers and broadcasters worked to limit congestion and enabled use of ordinary communication means even immediately after the disaster in some areas. Accordingly, disaster information was shared using diverse means that were not available in the past.

### 1. Information Transmission by Local Governments

## (1) Means Used for Information Transmission

At the time of the 2016 Kumamoto Earthquake, local governments used not only official disaster radio and disaster mails but also internet tools such as their official websites and SNS. Additionally, for elderly people who are apt to have difficulties in access to information, indirect publication using TVs and radios was actively employed. In this manner, more diverse means were effectively utilized for information transmission than at the time of the Great East Japan Earthquake.

## (2) Input of Information for Indirect Public Notices to the L-Alert System, etc

Information transmission using L-Alert is roughly divided into information on (emergency) evacuation instructions or evacuation recommendations and notices including daily living information and administrative information. Looking at the trend in the use of L-Alert, it is found that local governments in Kumamoto prefecture frequently issued evacuation instructions or recommendations using L-Alert up to the end of April, but that notices released in May onward were only limited to those input by Mashiki town. Local governments complain that it is troublesome to input information into the L-Alert system, while information recipients say that they confirmed the latest information at one time using other information collection means because all local governments' information was not necessarily available. Therefore, it is necessary to increase information input by local governments and the amount of available information on the L-Alert system.

### 2. Information Transmission by Residents (SNS)

The fact that disaster victims themselves transmitted information using Twitter or other tools is one of the characteristics of the 2016 Kumamoto Earthquake. Therefore, tweets posted after the earthquake that were processed using the DISAANA (DISAster-information ANAlyzer) developed by NICT were tabulated and analyzed. The DISAANA is a system that analyzes and organizes disaster-related tweets posted on Twitter to help people ascertain the situation and make proper judgment. The number of tweets posted on April 16, which was counted by predetermined category, was found to have increased each time an earthquake occurred.

### 3. Complementary Use of Diverse Information Transmission and Information Sharing Means

The 2016 Kumamoto Earthquake is characterized by the fact that information was collected from dispersed places using multiple ICT tools. Collected and utilized information was not limited to that universally broadcast using J-Alert, etc., which had already been put into practice. Local government officials themselves independently collected information and used tablet terminals for information integration and sharing. Additionally, SNS information sent by disaster victims was also used for ascertaining their needs.

In the meantime, during the emergency response period and reconstruction period, information on rescue activities, damages, and safety confirmation was collected to understand the overall damage and consider measures to take. In order to integrate and share such information collected by local government officials, mobile phones and tablet terminals were fully utilized.

In addition, during these periods, needs to collect information using SNS emerged for the purpose of grasping citizens' needs on a timely basis and collecting information necessary for pursuing duties in an efficient manner. However, when using SNS for information collection, there is a need to check the accuracy of information and properly select what is necessary from among a massive amount of information. Therefore, a tool to extract truly useful information or only necessary information from all information posted on SNS is required.

Use of SNS and dedicated disaster-response applica-