• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1257-1258
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1333-1334
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• 2005

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.74-75
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• 2013

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.2 s.54
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• pp.19-26
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• 2007

This paper presents the results of experimental studies of the mechanical characteristics of the Coil Spring and Viscous Damper system. The Coil Spring and Viscous Damper systems were selected for the isolation of Emergency Diesel Generator (EDG) which is located in Nuclear Power Plant (NPP). The Coil Spring and Viscous Damper systems were developed for the operating vibration isolation and seismic isolation for scaled Model EDG System. The damping properties of the viscous damper changes as the variation of velocity. Through this research nonlinear damping characteristics and the effective stiffness of coil spring and viscous damper system were evaluated.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.777-782
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• 2005

The importance of emergency diesel generator(EDG) has confirmed in the safety evaluation of PSA and the study on aging of EDG has been progressed actively as a part of the project of nuclear plant aging research in the U.S.A. As the result, the concept of performance evaluation is being transferred from statistical analysis of test results to performance monitoring and trending analysis for monitoring of aging and reliability. Recently, the study related aging characteristic and reliability for EDGS has begun in Korea. Consequently, the efficient performance monitoring based systematic and integrated monitoring and failure diagnostic technology is necessary. In the research, the knowledge basis of monitoring parameters for EDGS is constructed, and the prototype monitoring and diagnosis system applicable to Pielstick EDG is developed.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.264-270
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• 1998

This research broadens the prime concern of nuclear power plant operations from safe performance to both economic and safe performance. First emergency diesel generator is identified as one of main contributors for the lost plant availability through the review of plants forced outage records. The framework of an integrated architecture for performing modern on-line condition for operational availability improvement is configured in this work. For the development of the comprehensive sensor networks for complex target systems, an integrated methodology incorporating a structural hierarchy, a functional hierarchy, and a fault-system matrix is formulated. The second part of our research is development of intelligent diagnosis and maintenance advisory system, which employs Bayesian Belief networks (BBNs) as a high level reasoning tool incorporating inherent uncertainty use in probabilistic inference. Our prototype diagnosis algorithms are represented explicitly through topological symbols and links between them in a causal direction. As new evidence from sensor network development is entered into the model especially, our advisory of system provides operational advice concerning both availability and safety, so that the operator is able to determine the likely modes, diagnose the system state, locate root causes, and take the most advantageous action. Thereby, this advice improves operational availability

• Journal of Korean Society for Quality Management
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• v.25 no.3
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• pp.108-118
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• 1997

A commercial nuclear power station contains at least two emergency diesel generates(EDG) to control the risk of severe core demage during the station blackout accidents. Therefore the reliability of the EDG's to start and load-run on demend must be maintained at a sufficiently high level. Until now, a simple assessment of start and load-run success rates was used to calculate the EDG's reliability. However, this method has been found to contain many defects. Recently, the work of Martz et al.(1996) proposed the use of the Bayes estimator to find the EDG's reliability. In this paper, we will propose confidence interval for the Bayes estimator, compare the above two methods and, using practical examples, illustrate why the Bayes estimator method is more reasonable in our situation.

• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.453-464
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• 2001

A commercial nuclear power station contains at least tow emergency diesel generators(EDG) to control the risk of severe core damage during station blackout accidents. Therefore, the reliability of the EDG's to start and load-run on demand must be maintained at a sufficiently high level. Probabilistic safety assessments(PSA) are increasingly being used to quantify the public risk of operating potentially hazardous systems such as nuclear power reactors. In this paper, to perform PSA, we will introduce three different types of data and use Bayes procedure to estimate the error rate of nuclear power plant EDG, and using practical examples, illustrate which method is more reasonable in our situation.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.471-478
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• 2006

This paper presents the results of experimental studies of the mechanical characteristics of the Coil Spring and Viscous Damper system. The Coil Spring and Viscous Damper systems were selected for the isolation of Emergency Diesel Generator (EDG) which is located in Nuclear Power Plant (NPP). The Coil Spring and Viscous Damper systems were developed for, the operating vibration isolation and seismic isolation for scaled Model EDG System. The damping properties of the viscous damper changes as the variation of velocity. As a results, nonlinear damping characteristics of viscous damper system were evaluated.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.581-583
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• 2005

The paper is final report for speed control upgrade and analysis report which recently performed on PWR NPP safety related EDG KHNP Ulchin NPP No.2 Unit. The upgraded system includes more beneficial function like as 'Slow start with starting ramp', 'Generator load sensing & control capability' and 'Emergency ramp during slow start'. This paper shows functional operation of slow start regime according to NRC regulatory guide which guide regulation to NPP safety related environment.