As the need for infrastructure maintenance and management is increasing, innovation that is progressing ICT technology is expected to reduction and sophistication for maintenance. There are many research accumulation of Structural health monitoring such as detect structural damage or dynamic observation for grasping design values. On the other hand, few cases have been put to practical use in terms of inspection, diagnosis, and measures in actual maintenance and management. In this research, items to be evaluated in implementing the monitoring method are organized from the viewpoint of management, index, evaluation method, operation. We organized the evaluation axis for each item, and presented the way of innovation for positioning and extending existing cases.

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 Since 2007, Ibaraki University has installed electronic ventilated cases at 11 locations in Ibaraki prefecture and has been conducting fixed point observation of CO₂ concentration in the living area. However, it is not clear how much space is represented by the data obtained by fixed-point observation. Therefore, in this research, as the first step, we measured average CO₂ concentration between passes using DOAS method which can measure and analyze atmospheric components between passes, and compared with measured values by fixed point observation. Measurement was conducted in two directions of 3.7 km southwest and 2.4 km northeast starting from Ibaraki University, which is a fixed point observation point.
 As a result of examination, it was confirmed that the value of the DOAS method and the fixed point observation value was the difference of about ± 20 ppm, and both showed roughly the same CO₂ concentration representing the same area.

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 The Global Navigation Satellite System (GNSS), which uses more than one satellite to achieve high-precision positioning, is recently raising expectations for application in construction and other related fields such as civil engineering. This system is used currently in environments of with light satellite radio shielding such as construction sites. However, future systems will be used in urban areas. Therefore, its application in shielded environments such as those with tall structures must be examined. This study was conducted to evaluate the improvement effect of ratio of Fix solutions by high-precision multi-GNSS positioning of a car operating in a shielded environment. We analyzed data obtained in terms of the number and ratio of Fix solutions and the time interval between Fix solutions. Results show good ease of fixing, mostly in GPS+GLONASS+QZSS+BeiDou combination with favorable effects of satellite system use with a short time interval between Fix solutions.

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 This paper presents a visualization system based on simultaneous localization and mapping (SLAM) technology that enables 3D space recognition and self-localization. The present system is applied to the visualization for several numerical simulations of mechanical phenomena in indoors and outdoors. The validity and efficiency of the present method is investigated with the comparison of a conventional markerless AR system using landscape image as a marker.

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