We visualized transaction clusters on 3-dimensional digital earth using graph drawings, expressing their hierarchy by changing the altitude of the starting and ending points of the edges to be drawn. In addition, transaction clusters existing in chronological order were dynamically visualized using time slider application, and the color of edge to be drawn was changed according to the transaction amount of each edge. By the proposed method, it becomes possible to simultaneously grasp the position information of the nodes of the start and end nodes in the transaction cluster, the hierarchy of each node and the chronology. As the transaction clusters extracted under the same condition change in time, showing the change of transaction reflecing the strategy of the top companies. Therefore, the proposed method is proved useful in obtaining knowledge about transaction structure and chronology change from inter-firm transaction network regardless of the level of data analysis skill.

We developed the Aceh Disaster Digital Archive to make information about past disasters more accessible to communities. It employs an open-source data platform, allows free access, and is interactive and easy to use, which is essential for engaging the younger generation. Similar disasters can occur anywhere in the world, and by collecting multimedia data related pre-and post-tsunami Aceh, we have put it into a visual form and linked it with Social Network Services (SNSs) to facilitate the transfer of information and knowledge about earthquake and tsunami experiences in Aceh to promote sustainable disaster mitigation (Disaster Risk Reduction (DRR)). The materials were evaluated in local university to enhance tsunami learning.