• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.251-261
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• 2006

FMEA(Failure Mode and Effects)분석 기법이란 제품의 신뢰성을 높이기 위해, 잠재적 고장 모드를 선별하고 이의 고장 원인과 영향을 분석하여 고장이 제품에 미치는 영향을 최소화하기 위한 분석기법이다. 최근 FMEA기법이 많은 산업 분야에서 널리 쓰이고 있으며, 각 분야별로 그에 알맞게 특화된 FMEA기법이 제안되어 있다. 대표적으로 방산 분야의 MIL-1629a, 자동차 분야의 SAE-J1739 등을 들 수 있으며, 그 외의 많은 산업분야에서도 특화된 FMEA규격을 사용하고 있다. 하지만 높은 신뢰성이 요구되는 철도 산업의 경우에는 아직까지 특화된 FMEA규격은 제시되어 있지 못한 실정이다. 본 논문에서는 SAE-J1739,MIL-1629a, IEC-60812의 규격을 비교 분석함으로써 철도 시스템에 특화된 FMEA규격을 제안하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1394-1400
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• 2008

This study investigates the Failure Modes, Effects and Criticality Analysis (FMECA) Method for the railroad vehicle. Recently, RAMS (Reliability, Availability, Maintainability and Safety) is one of the most important issues in the railroad industry. FMECA is prerequisite for the RAMS Analysis, and it is a procedure to identify the potential failure modes and their effects and to reduce or mitigate the critical effects on the system. FMECA is used in various industries and it is specialized in each industry. For instance, MIL-1629a and SAE-J1739 are specialized FMECA method for Military industry and Automotive industry, respectively. Although the railroad industry requires the high reliability system, it does not have a specialized FMECA yet. Thus, in this paper, an FMECA method specialized to the railroad vehicle was proposed through analyses and comparison of the MIL-1629a, SAE-J1739 and IEC-60812 standards.

• Industrial Engineering and Management Systems
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• 제13권1호
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• pp.87-100
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• 2014

Risk management is recognized as a significant element in Information Security Management while the failure mode and effects analysis (FMEA) is widely used in risk analysis in manufacturing industry. This paper aims to present the development work of the Information Security FMEA Circle (InfoSec FMEA Circle) which is used to support the risk management framework by modifying traditional FMEA methodologies. In order to demonstrate the "appropriateness" of the InfoSec FMEA Circle for the purposes of assessing information security, a case study at Hong Kong Science and Technology Parks Corporation (HKSTP) is employed. The "InfoSec FMEA Circle" is found to be an effective risk assessment methodology that has a significant contribution to providing a stepwise risk management implementation model for information security management.

• 간호행정학회지
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• 제21권3호
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• pp.254-262
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• 2015

Purpose: This study was done to apply failure mode & effect analysis (FMEA) to chemotherapy in order to reduce prescribing, dispensing and administering errors related to treatment and provide patients with a safe medical environment. Methods: A one group pre-post test design was used to verify the effects using the tool for FMEA in chemotherapy. Results: There was a statistically significant decrease in prescribing errors from 11.47% to 3.18%; administering errors decreased but they were not statistically significant. In a addition, there was no change in dispensing errors. Conclusion: The results show that FMEA removed risk factors that might occur during the process of chemotherapy and that it was an effective tool for prevention of negligent accident occurring in actual patients.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.261-262
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• 2008

Failure Mode Effects and Criticality Analysis (FMECA) evaluates criticality and severity of each failure mode. Generally, those indices are determined subjectively by experts and operators. However, this process has no choice but to include uncertainty. In this paper, a method for eliciting expert opinions considering its uncertainty is proposed to evaluate the criticality and severity. In addition, a fuzzy expert system is constructed to determine the crisp value of risk level for each failure mode. The results are worth considering while deciding the proper policies for each component of the system.

• Geomechanics and Engineering
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• 제29권5호
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• pp.567-582
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• 2022

In the present study, a series of physical experiments and numerical simulations were conducted to investigate the effects of mode I and mixed-mode I/II cracks on the fracture modes and stability of roadway tunnel models. The experiments and simulations incorporated different inclination angle flaws under both static and dynamic loads. The quasi-static and dynamic testing were conducted by using an electro-hydraulic servo control device and drop weight impact system (DWIS), and the failure process was simulated by using rock failure process analysis (RFPA) and AUTODYN software. The stress intensity factor was also calculated to evaluate the stability of the flawed roadway tunnel models by using ABAQUS software. According to comparisons between the test and numerical results, it is observed that for flawed roadways with a single radical crack and inclination angle of 45°, the static and dynamic stability are the lowest relative to other angles of fractured rock masses. For mixed-mode I/II cracks in flawed roadway tunnel models under dynamic loading, a wing crack is produced and the pre-existing cracks increase the stress concentration factor in the right part of the specimen, but this factor will not be larger than the maximum principal stress region in the roadway tunnel models. Additionally, damage to the sidewalls will be involved in the flawed roadway tunnel models under static loads.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.11-21
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• 2019

In product design, the initial design stage is being increasingly emphasized because it significantly influences the successive product development and production stages. However, for larger and more complex products, it is very difficult to accurately predict product reliability in the initial design stage. Various design methodologies have been proposed to resolve this issue, but maintaining reliability while exploring design alternatives is yet to be achieved. Therefore, this paper proposes a methodology for conceptual design considering reliability issues that may arise in the successive detailed design stages. The methodology integrates the independency of axiomatic design and the hierarchical structure of failure mode, effects, and criticality analysis (FMECA), which is a technique widely used to analyze product reliability. We applied the proposed methodology to a liquefied natural gas fuel gas supply system to verify its effectiveness in the reliability improvement of the design process.

• 한국항행학회논문지
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• 제27권4호
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• pp.436-446
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• 2023

안전 필수 분야의 전장 장비에서 다양한 고장요인 (고장모드)에 따른 고장 영향 분석 (FMEA, Failure Mode and Effects Analysis)이 필수적이다. 이는 기기나 시스템의 잠재적인 결함들을 식별하고, 그로 인한 발생 가능한 위험을 평가하여 이를 방지하거나 관리하기 위한 개선안을 수립한다. 그러나 최근 시스템의 복잡성이 증가하고 소프트웨어의 영향이 중요해지며 전통적인 FMEA 만을 설계 단계에 적용하는 것이 어려운 상황이다. 본 논문은 모델기반설계기법을 기반으로한 Automatic FMEA 방식을 제안한다. 모델의 구조와 동작을 자동으로 분석하여 FMEA를 수행할 수 있게 하여, 설계 초기 단계에서도 고장모드 분석이 가능하게 한다. 사례연구로 차량 연료 제어 시스템을 대상으로 Automatic FMEA를 수행하였다. 본 연구는 Automatic FMEA 분석도구의 성능을 입증하는 동시에, 향후 연구 방향을 제안한다.

• Structural Engineering and Mechanics
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• 제78권1호
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• pp.41-52
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• 2021

Inelastic static pushover analysis has been used in the academic-research widely for seismic analysis of structures. Nowadays, the variety pushover analysis methods have been developed, including Modal pushover, Adaptive pushover, and Cyclic pushover, in which some weaknesses of the conventional pushover method have been rectified. In the conventional pushover analysis method, the effects of cumulative growth of cracks are not considered on the reduction of strength and stiffness of RC members that occur during earthquake or cyclic loading. Therefore, the Cyclic Pushover Analysis Method (CPA) has been proposed. This method is a powerful technique for seismic evaluation of regular reinforced concrete buildings in which the first mode of them is dominant. Since the bridges have different structures than buildings, their results cannot necessarily be attributed to bridges, and more research is needed. In this study, a cyclic pushover analysis with four loading protocols (suggested by valid references) by the Opensees software was conducted for seismic evaluation of two regular reinforce concrete bridges. The modeling method was validated with the comparison of the analytical and experimental results under both cyclic and dynamic loading. The failure mode of the piers was considered in two-mode of flexural failure and also a flexural-shear failure. Along with the cyclic analysis, conventional analysis has been studied. Also, the nonlinear incremental dynamic analysis (IDA) method has been used to examine and compare the results of pushover analyses. The time history of 20 far-field earthquake records was used to conduct IDA. After analysis, the base shear vs. displacement in the middle of the deck was drawn. The obtained results show that the cyclic pushover analysis method is able to evaluate an accurate seismic behavior of the reinforced concrete piers of the bridges. Based on the results, the cyclic pushover has proper convergence with IDA. Its accuracy was much higher than the conventional pushover, in which the bridge piers failed in flexural-shear mode. But, in the flexural failure mode, the results of each two pushover methods were close approximately. Besides, the cyclic pushover method with ACI loading protocol, and ATC-24 loading protocol, can provided more accurate results for evaluating the seismic investigation of the bridges, specially if the bridge piers are failed in flexural-shear failure mode.

• 시스템엔지니어링학술지
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• 제9권1호
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• pp.65-84
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• 2013

This paper introduces a systems engineering approach to reliability centered maintenance to address some of the weaknesses. Reliability centered maintenance is a systematic, disciplined process that produces an efficient equipment management strategy to reduce the probability of failure [1]. The study identifies the need for RCM, requirements analysis, design for RCM implementation. Value modeling is used to evaluate the value measures of RCM. The system boundary for the study has been selected as containment spray pump and its motor drive. Failure Mode and Criticality Effects analysis is applied to evaluate the failure modes while the logic tree diagram used to determine the optimum maintenance strategy. It is concluded that condition based maintenance tasks should be enhanced to reduce component degradation and thus improve reliability and availability of the component. It is recommended to apply time directed tasks to age related failures and failure finding tasks to hidden failures.