In the future social infrastructure diagnosis for concrete structures such as bridges, tunnels and buildings, it is expected that the digital hammering inspection, which is objective, quantitative, and recordable to the conventional hammering inspection, will play a significant role. However, since there are a wide variety of defects due to poor construction and age-related deteriorations in the concrete structures, they have not been quantitatively identified enough by the digital hammering inspection in t...
英字タイトル:
A study on internal structure diagnosis of concrete structures incorporated with digital hammering inspection, AI and simulation technologies (1) Direct problem analysis using AI

One of the most common inspection methods for concrete structures is hammering inspection. While this method makes it possible to quickly inspect a vast number of inspection targets, it has the problem of lacking objectivity of judgment results and recordability. In this study, we aimed to develop a technology to quantitatively diagnose the internal structure of concrete structures by digital hammering inspection. The approach of the research was to build an AI trained by CNN with a database that relates th...
英字タイトル:
A study on internal structure diagnosis of concrete structures incorporated with digital hammering inspection, AI and simulation technologies (2) Inverse problem analysis using AI

For decommissioning of the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company Holdings, Incorporated, we are now developing remote laser diagnostic techniques for integrity evaluation of support structures. Ultrasonic waves were induced on a sample by an impact laser. The waves propagating through the sample were detected with a laser Doppler vibrometer using a measuring laser. This technology enables remote, non-contact diagnosis....
英字タイトル:
Characteristics of structures using laser diagnostic techniques

We are developing the inspection technology for laser micro spot welding. Butt welding for the inner wall of heat exchanger tubes were successfully carried o ut by a composite-type optical fiber scope. The related technologies are the f ollowing : Rapid inspection by Eddy Current Testing Fiber endoscope observation 3 Synchrotron X-ray absorption contrast method. These technologies are versatile to be applied in maintenance for industrial production plants....
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Development of Inspection Technology for Laser Welding Section

Abstract As an attempt to apply AI in the field of maintenance, we have been studying "forward analysis", "inverse analysis" and "future prediction". As for the “forward analysis”, as a theoretical verification of the digital hammering inspection results using the AE sensor, the natural frequency obtained in the hammering inspection is confirmed by “time history response analysis”. Because there is a combination of the shape, material properties to be inspected, measuring position of natural frequency, etc....
英字タイトル:
Attempts of forward analysis, reverse analysis and future prediction using AI in the field of maintenance

For decommissioning of the Fukushima Daiichi Nuclear Power Station, installation of an optical fiber seismic vibrometer using a specially designed robotic system was demonstrated. A water tank with 4.5m diameter and 5m depth was used as a demo-plant of tank type critical assembly. Micro-earthquake response of a water tank was detected by the optical fiber seismic vibrometer. Vibration characteristic of the window of the water tank was monitored by laser Doppler interferometer....
英字タイトル:
Development of micro-earthquake response detection by optical fiber seismic vibrometer with a water tank and a specially designed robotic system

保全分野では点検、検査、モニタリングによる有用なBIG DATAが存在する。また、複雑な非線形シミュレーションが必要であり、ヒューマンエラー低減、働き方改革では非線形な人間系の分析が必要となる。ここでは保全分野へのAI適用性を考察する。...