The importance of nuclear security increased after FuNushima Daiichi nuclear power plant accident. Especially as a threat to nuclear power plants, sabotage by insider is worthy of attention. In response to this situation, hand motion is an important part of human activity and it has high contribution to high-accuracy detection of insiders’ sabotage. Moreover, Time series data analysis is a useful method in abnormal behavior detection. In this research, the real-time hand motion detection system was develope...
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Detection of Insiders’ Sabotage using Time-Series Data Analysis of Hand Motion

Piping and Instrumentation Diagrams (P&IDs) contain information about the piping and process equipment together with the instrumentation and control devices, which is essential to the design and management of Nuclear Power Plants (NPPs). There are abundant complex objects on P&IDs, with imbalanced distribution of these objects and their linked information across different diagrams. The complexity of P&IDs thus is increased which make automatic identification difficult. Therefore, the content of P&IDs is gen...

In this study, the prediction method for time-series data was developed and its validity was verified by the comparison of the measured time-series and the predicted one. The measured time-series data was obtained as the laser displacemen t meter's output observing the human's chest movement during breathing. The Singular Spectral Analysis method (SSA) was applied as the prediction analysis method. The comparison showed good agreement of the measured and the predicted ones....
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Diagnosis of Dynamic Equipments by SSA Method

We have developed a new index called Resilience index, which evaluate the reliability of system safety of nuclear power plant under severe accident by considering the capability to recover from the situation the system safety function was lost. In this paper, a detailed evaluation procedure for the Resilience index was described. System safety of a PWR plant under severe accident was then assessed according to the Resilience index concept to discuss applicability of the index. We found that the Resilie...
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Fundamental Study on Applicability of Resilience Index for System Safety Assessment

We have established a procedure for comprehensive safety assessment of aging plant using a combination of two indices; risk index and resilience index. And, we have identified important equipment using a simple resilience index and have extracted failure mode using a risk index with detailed plant model. Those were applied to three loop PWR plant as trials. We are reporting its summary and considering the effectiveness of the resilience index. ...
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Development of Comprehensive Safety Assessment Method for Aging Nuclear Power Plant Using Risk Index and Resilience Index

Rapid response processes are essential for enabling resilience, which provides a potential target for assessment. The response cycle is considered in three phases: (1) information transmission from system to Decision-Maker, (2) information processing, and (3) feedback action on the system. This research focuses on the first of the three phases, information transmission, and proposes a novel resilience assessment using an Information-Theoretic approach. From this point of view, resilience is considered t...
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An Information-Theoretic Approach to Resilience Assessment

We have proposed new indices for evaluating resilience, that is, the response margin and response reliability of a nuclear power plant during an accident and detailed procedure for assessing those indices. In this study, the resilience of a simple fast reactor plant model is evaluated according to the indices. The applicability of the resilience evaluation method to fast reactor plants is then discussed from the viewpoints of reflecting the characteristics of each reactor type....
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Fundamental Study on Applicability of Resilience Evaluation Method to Fast Reactor Plants

Abstract In recent years, there are so many systems using movie. So, we propose a new method to predict the near-future images using movie. To predict the movi e, the Principal Component Analysis (PCA) and Multi-Channel Singular Spectrum Analysis (MSSA) are used in this method. Predicted movie obtained from this metho d is almost the same as the original movie, but improvement is required to reduce the calculation time and to increase the precision of the prediction for real -time image prediction. So, in ...
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Technological Improvement of Movie Prediction Method by PCA and MSSA

In this research, a new index “The Resilience Index” was proposed to evaluate the capability of nuclear power plant to recover from the situation of safety function lost. Three elements assumed to evaluate the resilience index are the achievement rate, necessary time, and probability of success of each accident management activity. The resilience index is expected to visualize the improvement of safety of each nuclear power plant against severe accidents. ...
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Development of Resilience Evaluation Method for Nuclear Power Plant (Part 1: Proposal of Resilience Index for Assessment of Safety of Nuclear Power Plant under Severe Accident)

This study proposes a method to search the optimum maintenance program of the nuclear power plant based on the maintenance equations approach. The maintenance equations consider the reliability an d the cost of the maintenance of the power plant and evaluate them quantitatively as the functions . By solving the minimum problems of the equations, the optimum maintenance program can be derived....
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Development of Optimum Maintenance Program based on the Maintenance Equations