From two experiments, effect of drill map presentation for reading task of hazard map was examined. Two experiments were conducted to determine whether providing specialized projected volcanic activity maps (drill maps) resulted in improved interpretation of publicly available volcanic hazard maps.
In the first experiment, 113 junior high school students and 33 university students were required to formulate a plan of action in the event of a volcanic activity alert working in pairs. This task was carried out by two groups of participants: an experimental group and a control group. For the experimental group, a drill map showing projected lava flows from three different volcanic craters was presented before the task. The participants also filled out a questionnaire regarding their level of knowledge about volcanic hazards and their impressions about the task. Although no difference in performance was discernable in relation to the questionnaire responses, the general quality of plans produced by the experimental group was better than the control group.
In the second experiment the task, carried outindividually, was to evaluate the urgency to evacuate at six different locations shown on a hazard map under three different hypothetical situations: 1) a volcanic activity advisory, 2) volcanic activity alert with an assumed crater location, and 3) volcanic activity alert with a different assumed crater location. Forty-two university students were randomly assigned to either the control group or the experimental group. The experimental group participants were presented with a drill map and given an explanation of the drill map. The same task was also given to ten experts on volcanic activity. The evaluation of the threat was significantly different a one location (location E) between situation 2 and 3 in the control group while at three locations (A, C, & D) in the experimental group and at two locations (location A & D) in the expert group. Also, a comparison between the three groups showed that the evaluations of the experimental group were similar to those of the experts. This indicates that presentation of drill maps enables adults with no special knowledge about hazard maps to evaluate the urgency of the threat due to volcanic activities more accurately from hazard maps.

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In supervised classification of land cover, ground truth data are used as training data for classification, or for post-classification validation of data. In classifying a large area, it is difficult to collect enough ground truth data. This study proposed a method of collecting ground truth data using both existing land cover data and existing land use data. By combining these two types of data, more reliable regions can be extracted as ground truth data. Using ground truth data collected by this method in China, a larger region was classified as a trial. The classification accuracy was 81% when the results were evaluated using the ground truth data. For the practical use, combining the ground truth data collected by the proposed method with those collected by the other method is recommended to enrich ground truth data inventories.

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