Satellite SAR has been widely used in many fields such as monitoring of crustal movements caused by large earthquakes and has been mainly made great achievements as the monitoring technology at the time of relatively wide area disasters. The surface of the area to be observed by the satellite SAR is a very wide area with dozens km square and the spatial resolution and the analysis methods have been improved in recent years.
 Advanced Land Observing Satellite (ALOS) with a Phased Array L-band SAR (PALSAR) sensor (ALOS/PALSAR) was launched by Japan Aerospace Exploration Agency (JAXA) in January 2006 and completed the operation in May 2011 (JAXA). In this paper, we used ALOS/PALSAR data for SAR based external deformation monitoring of five rockfill dams in the same ALOS/PALSAR data. External deformations of five rockfill dams for about four years were calculated by SAR and compared with other methods such as GPS or electro-optical survey. The average root mean square error (RMSE) of external deformations of five rockfill dams between SAR and other methods resulted in about 5 mm. We investigated effects of angles between slopes of dam surfaces and illumination directions and angles of incidences on the accuracy of external deformations. We found that variations of RMSEs tented to be larger when angles of incidences were larger.

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 In recovery and reconstruction after disaster, Unmanned Construction System (UCS) is used for the purpose of ensuring safety of operators. Reduction in the work efficiency of the UCS has become a major issue. Part of the cause could be the low spatial resolution and lack of depth information in the video the operators watch. In the present study, we compared the efficiency of the performance of the task similar to the work done in the disaster recovery site of Mt. Unzen under the proposed image environment with that currently used there. The proposed environment consisted of stereoscopic 3D video of uncompressed 4K resolution (3840×2160 pixels) for each eye presented on a large display while the current environment was 2D compressed video of low resolution taken by multiple cameras presented on multiple small displays. The proposed environment improved work efficiency by 23-35% compared with the current one.

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 A new method using GPS is proposed for dynamic displacement monitoring. The method is characterized by a three-dimensional dynamic displacement that can be measured with high accuracy. It is based on a carrier phase observation technique, like GPS relative positioning, and takes a time differential carrier phase, while it requires only one sensor as in GPS single positioning. Thus, it is called self-relative single positioning. This paper describes the formulation of the method, the experiment results for investigating the ability of the newly developed sensor, and a practical application of the method to monitoring a floating pier. The proposed method uses a new sensor that can monitor dynamic displacements of more than 5 mm of amplitude and less than 2 Hz of frequency.

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 Road users desire that changes in roads are quickly reflected to maps and car navigation systems. Therefore, Cartographers collect information about roads into service and road openings (road change events) from all over the country at an early date. On the other hand, road administrators make official notices based on the Road Law at the start of service of the road and decision / change of the road area, and orderers of the road construction manage the information of the construction for the proper execution of public works. If these administrative information can be used to grasp the information about road change events, it will be possible to improve the efficiency of information gathering for reliable map updating. In this research, we propose a method to associate information related to road change events, and investigated the actual circumstances surrounding the information about road changes by this method. Based on the survey, we estimated the prediction of opening from construction and evaluated its possibilities. In addition, we built an integrated system which was able to visualize information, and are promoting activities about open data related to road change events.

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