狩川 大輔 Daisuke KARIKAWA Abstract The discussions in the committee for investigation of the integrity and safety of the Kas hiwazaki-Kariwa nuclear power plant after earthquake has been analyzed to clarify what is important in the explanation of the technical details. The results imply that the consideration of the unstate d assumptions and the variety of the level of understanding should be carefully taken into account....
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Unstated knowledge required in the communication for describing safety of nuclear power plant

Abstract The purpose of this study is to develop a method for quantitative evaluation of the running cost and safety in a Nuclear Power Plant (NPP). A new model for numerical evaluation is proposed based on the concept where the four issues such as Cost of Electricity (COE), maintenan ce cost, loss by the failures, and several risks are evaluated statistically by using the Monte Carlo simulation. The results show different d ependence on the parameters used in the model. These results would be useful to d...
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Development of quantitative evaluation method for the cost and safetyin maintenance plan of Nuclear Power Plant

In the present study, early detection of anomaly and failure identification have been studied based on the signals simulated based on the real plant parameters. The specific feature of the present method is the use of similarity defined based on the multi-attributes of measured parameters. The frequency and time domain characteristics have been adopted as the attributes showing the symptom of failures. The five failure transients and four kinds of specific signal anomaly have been simulated and used as...
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Anomaly Diagnosis based on Multi-attribute Similarity

The framework of intelligent support system for the maintenance of nuclear power plant is proposed in this paper with emphasis on the combined use of a portable device and intelligent information processing. The purpose of this system is the realization of flexible inspection process and effective diagnosis process to be performed on-site. The prototype system has been implemented for the experimental facility with mobile-agent technology and PDA (personal digital assistant) to show the basic function...
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Development of Maintenance Support System using Portable Device and Mobile Agent

Clean-up activity of spent fuel powder (UO2 powder etc.) in mechanical treatment cell was performed for the purpose of the preparation of decommissioning at TRP.For the clean-up activity, we selected an inexpensive vacuum cleaner and made tools, that was improved taking into account of use by means of a crane or a manipulator in the high dose cell, and applied it after a mock-up test.We report our experience and knowledge provided through this clean-up activity....
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Clean-up activity of spent fuel powder (UO2 powder) in mechanical treatment cell at Tokai reprocessing plant

The evaluation method for maintenance optimization in long-term operation of nuclear power plant (NPP) has been proposed by using Probabilistic Safety Assessment (PSA) in general. Possible troubles in the maintenance activities of NPP are modeled and simulated by using Fault Tree with failure rates of components estimated by operating experiences in Japan. The Monte-Carlo simulation has been performed to compare the maintenance strategies such as cycle extension of periodic inspection and overhaul for...
英字タイトル:
Development of an Evaluation Method for Maintenance Optimization in Long-term Operation of Nuclear Power Plant with Probabilistic Safety Assessment