• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.1905-1909
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• 2008

As catenary supply electric power directly to the railway system, it is very important to prevent an accident of a catenary for appropriate train operations. This paper analyzed the outage data for British catenary safety analysis report and Korean data to compare the reliability of the railway systems. The analyzed data were applied to Fault Tree Analysis(FTA) algorithm to calculate the reliability indices of a railway system. Failure rate of an electric railway system through FTA were calculated for each element and the entire railway system. The reliability indices can be used to determine the eqipment to be replaced for the entire system reliability improvement.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.401-406
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• 2000

Fault tree analysis (FTA) is a widely used methodology for reliability analysis. The method is useful in that it suggests a very comprehensive way of describing the hierarchical relations of causes of faults and the corresponding results. However it is difficult to get appropriate fault trees for given products or systems without very profound knowledge and experience. This work aims to develop a methodology of fault tree construction using the results of function deployment for machine parts, which provides an objective way of preparing fault trees. The failure modes are defined to each function network generated by the function deployment method and the fault tree with respect to each viewpoint is constructed by arranging the failure modes. The fault tree is finally obtained by synthesizing the fault trees with respect to each viewpoint. The example of fault tree construction is also shown.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.12 no.20
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• pp.1-24
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• 1989

This paper takes aim at the reliability evaluation by application of Fault Tree Analysis and its computerization. FTA is one of the methods for evaluation of system reliability and safety analysis. The important characteristic of this paper is that computer program is written in the package program(dBaseIII+) by 16Bit/AT personal computer. The program consists of three program segments. (1) The minimal cut sets of the system fault tree are obtained by means of "Fault tree reduction algorithm" (2) The minimal path sets are obtained by inversion of the minimal cut sets determined from fault tree (3) The importance of the basic events which are presented in the minimal cut sets is obtained by means of structural importance analysis. In this paper, a Fault Tree Analysis is applied to a BAG FILTER which is a kind of dust collector.collector.

• Journal of Industrial Technology
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• v.26 no.B
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• pp.145-155
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• 2006

High level of reliability in facility operation is specifically required these days. The goal of this study is to secure a methodology for reliability analysis of hydro-power plant so that an appropriate decision for operation and investment can be made. Fault tree analysis of water supply system within hydro-power plant has been performed in this study. We briefly examined the electric power generation facility and water supply system. We then developed fault tree for the water supply system based on failure modes and effects analysis. We conclude this study and provided future research areas.

• Journal of Korea Multimedia Society
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• v.20 no.11
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• pp.1793-1802
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• 2017

In the recent years, IT and Network Technology has rapidly advanced environment in accordance with the needs of the times, the usage of the smart learning service is increasing. Smart learning is extended from e-learning which is limited concept of space and place. This system can be easily exposed to the various security threats due to characteristic of wireless service system. Therefore, this paper proposes the improvement methods of smart learning system security by use of faults analysis methods such as the FTA(Fault Tree Analysis) and FMECA(Failure Mode Effects and Criticality Analysis) utilizing the consolidated analysis method which maximized advantage and minimized disadvantage of each technique.

• The Journal of the Korea Contents Association
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• v.11 no.10
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• pp.49-58
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• 2011

Fault Tree Analysis(FTA) builds fault trees to perform safety analysis of systems. However, building fault trees depends on domain knowledge and expertize on target systems and consumes lots of time and efforts. In this paper, we propose a technique that builds fault trees systematically based on state-transition models which are software design artifacts. For the end, this paper identifies conditions that should be satisfied to guarantee safety of state-transition models and develop templates for fault tree construction. This paper also describes the results of appling the proposed method to railway crossing control system.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.5
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• pp.110-123
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• 1994

The development of automatic production systems have required inteligent diagnostic and monitoring function to repair system failure and reduce production loss by the failure. In order to perform accurate functions of intelligent system, inferencing about total system failure and fault analysis due to each mechanical component failures are required. Also the solution about repair and maintenance can be suggested from these analysis results. As an essential component of mechanical system, a bearing system is investigated to define the failure behavior. The bearing failure is caused by lubricant system failure, metallurgical defficiency, mechanical condition(vibration, overloading, misalignment) and environmental effect. This study described roller bearing fault train due to stress variation and metallurgical defficiency from lubricant failure by using FTA.

• International Journal of Safety
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• v.7 no.1
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• pp.15-20
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• 2008

The primary goal of this study is to analyze fire hazards of electric home appliances such as electric iron and electric heater using fault tree analysis(FTA). A fault tree(FT) is constructed and used to analyze fire hazards in electric home appliances. The fault tree is built from events that may occur in electric home appliances. The failure rate of basic events are derived from the value of experimental results and reference. And an algorithm analyzing fire in electric home appliances is suggested. We show how fault tree analysis, carried out by means of failure rate, is able to diagnose fire hazards of electric home appliances in a precise manner. We present numerical results such as fire probability of electric home appliances, importance measure, fire cause, etc. It can be helpful in preventing the fire hazards in electric home appliances.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2022.10a
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• pp.227-228
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• 2022

전통적인 HRA(Human Reliability Analysis)방법은 특정 애플리케이션 또는 산업을 염두에 두고 있으며. 또한 이러한 방법은 종종 복잡하며, 시간이 많이 걸리고 적용하는 데 비용이 많이 들며 직접 비교하기에는 적합하지 않다. 제안된 HFHM(Human Factors Hazard Model: 인적 요인 위험 모델)은 기검증되고 시간 테스트를 거친 FTA(Fault Tree Analysis:결함 트리 분석)및 ETA(Event Tree Analysis:이벤트 트리 분석)의 확률 분석 도구 및 새로 개발된 HEP(Human Error Probability:인적 오류 확률)예측 도구와 통합되고, 인간과 관련된 PSF(Performance Shaping Factors:성능 형성 요인)를 중심으로 새로운 접근 방식으로 개발되었다. 인간-시스템은 상호작용으로 인한 재난사고 가능성을 모델링하는 위험분석 접근법 HFHM은 다음과 같은 상용 소프트웨어 도구 내에서 예시되고 자동화된다. HFHM에서 생성된 데이터는 SE 분석가 및 설계에 대한 표준화된 가이드로 사용될 수 있다. 본 연구에서는 인적 위험을 예측하는 이 새로운 접근 방식을 통해, 전체 시스템에 대한 포괄적인 재난안전 분석을 가능하게 한다.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2574-2576
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• 2002

본 논문에서는 가압형 액체 추진 로켓인 KSR-III의 위험도 관리에 Fault Tree Analysis (FTA)를 적용한다. 미니멀 컷 set과 같은 FTA 구조 분석 방법을 소개하고, KSR-III 비상엔진중단 상황에 대해 정성적 FTA를 적용한다. 정성적 FTA를 통해서 KSR-III 추진기관 시스템의 구조적 특성을 명확히 하고 비상엔진중단을 야기시키는 컴포넌트 레벨에서의 실패와 작동 시퀀스의 조합에서의 문제 등을 명확히 하였다.