• Structural Engineering and Mechanics
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• 제91권3호
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• pp.279-289
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• 2024

The purpose of this study is to represent a useful alternative for the preliminary seismic vulnerability assessment of existing reinforced concrete buildings by introducing a statistical approach employing the binary logistic regression technique. Two different predictive statistical models, namely full and reduced models, were generated utilizing building characteristics obtained from the damage database compiled after 1999 Düzce earthquake. Among the inspected building parameters, number of stories, overhang ratio, priority index, soft story index, normalized redundancy ratio and normalized lateral stiffness index were specifically selected as the predictor variables for vulnerability classification. As a result, normalized redundancy ratio and soft story index were identified as the most significant predictors affecting seismic vulnerability in terms of life safety performance level. In conclusion, it is revealed that both models are capable of classifying the set of buildings being severely damaged or collapsed with a balanced accuracy of 73%, hence, both are able to filter out high-priority buildings for life safety performance assessment. Thus, in this study, having the same high accuracy as the full model, the reduced model using fewer predictors is proposed as a simple and viable classifier for determining life safety levels of reinforced concrete buildings in the preliminary seismic risk assessment.

• 대한안전경영과학회지
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• 제14권3호
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• pp.39-48
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• 2012

Risk Assessment to list possible safety disasters and their probability and severity is the starting point for effective safety management on construction project site. However, the safety managers in owners, construction supervisors, contractors, and sub-contractors still have difficulties in judging the priorities of safety activities and preparing responses to each potential safety disasters. Therefore, this study aimed to suggest a systematic method in assessing safety risk prior to commencement with the agreement of stakeholders. FMECA(failure mode effects and criticality analysis) was selected as a main assessment tool and it was modified according to the characteristics of construction projects and trades. Each risk is, firstly, evaluated with occurrence probability, possible loss and impacts to projects, and detections, and then risk priority number(RPN) is calculated. Subsequently, the managers of each stakeholder discuss the types, timing, and responsibilities of responses as a group decision-making process.

• 한국안전학회지
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• 제19권4호
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• pp.36-41
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• 2004

This paper presents an qualitative assessment for hazard on the electric power installations of a construction field using FMEL The power installations have the mission to maintain the highest level of service reliability on the works. The more capital the electric power invest the higher service reliability they plausibly will achieve. However, because of limited resources, how effectively budgets can be allocated to achieve service reliability as high as possible. The assessment typically generates recommendations for increasing component reliability, thus improving the power installation safety. The FMEA tabulates the failure modes of components and how their failure affects the power installations being considered. Tn order to estimate the risks of a failures, the FMEA presents criticality estimation or risk priority number using the severity, occurrence, and detectability. The results showed that the highest components of the risk priority number among components were condenser, transformer, MCCB and LA. And In case of the criticality estimation, the potential failure modes were abnormal temperature rise, insulation oil leakage, deterioration for the transformer, overcurrent for the MCCB and operation outage fir the LA.

• 한국산학기술학회논문지
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• 제11권5호
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• pp.1601-1607
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• 2010

본 논문에서는 FMEA (Failure Mode Effect Analysis) 기법을 적용한 우편기계 유지보수 방법 제시하였다. 제안된 방법은 우편기계 모듈 및 부품에 대해 고장 유형을 정의하고, 고장 유형별 시스템에 주는 영향과 고장 빈도 및 검출도 등을 정의하여 고장 유형에 대한 시스템 위험도를 계산하여 그 값에 기반하여 점점 항목과 점검 주기를 조정하도록 하므로 시스템의 고장을 사전에 예방하고 시스템 가동율을 높이도록 하는 효율적인 유지보수 방법이다. 실제 현장에서 운영되고 있는 소형 통상 우편 구분 기계에 대해 제안된 방법의 적용 예를 보였다. 따라서 제안된 방법은 향후 국내 우편기계 유지보수에 적용시 유지보수 용이성과 효율성을 높일 것으로 기대한다.

• 지질공학
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• 제23권3호
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• pp.257-269
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• 2013

산사태나 비탈면 재해를 예방하기 위해서는 적절한 계획을 수립하여야 하며, 국가의 한정된 예산을 고려했을 때 체계적인 투자 계획이 마련되어야 한다. 국도 도로비탈면의 체계적인 관리와 합리적 투자 계획 수립을 위하여 위험도와 예상피해도를 고려하여 투자우선순위를 산출하였다. 투자우선순위에서 위험도 결정의 주요인자는 경사, 토질, RMR, 안정석해석, 불연속면 종류, 붕괴이력이며, 피해도는 교통량과 차선수, 평균차량위험도를 고려하여 결정하였다. 강원도 영서지방 392개소 비탈면에 대한 투자우선순위 산출 및 회귀분석 결과, 붕괴가 발생된 비탈면의 투자우선순위가 높은 것으로 확인되며, 위험구간비가 높은 비탈면, 계곡부가 존재하는 비탈면이 높은 투자우선순위를 차지하는 것으로 확인된다.

• 벤처창업연구
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• 제9권1호
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• pp.177-186
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• 2014

FMEA는 실패로 인한 위험을 최소화하기위해 실패의 요인과 그로인한 영향을 사전에 평가하는 체계적인 방법이다. 이 방법은 제품의 신뢰도 문제를 해결하기 위해 제조산업 분야에서 주로 사용되어 왔으나, 서비스의 역할과 중요성이 커지면서 최근에는 이를 서비스의 신뢰도 문제에도 사용하고 있다. 하지만, 서비스에서는 고객이 서비스 전달 프로세스에 참여하며 고객마다의 이질성 등으로 인해 제조업을 위해 개발된 FMEA를 직접 사용할 수은 없다. 이러한 이유로 인해, FMEA를 서비스에 적용하기위한 여러 연구가 이루어지고 있다. 본 논문에서는, 심각도, 발생빈도, 검출력으로 우선순위를 평가하던 기존의 RPN 대신에, 서비스 특성을 고려하여 심각도, 발생빈도, 회복력 3가지로 평가하는 새로운 지수 S-RPN을 제시하였으며, 기존연구의 사례를 통해 제시된 방법의 효용성을 평가하였다.

• 한국안전학회지
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• 제28권4호
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• pp.81-90
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• 2013

To meet increased demand and lead to execution of successful overseas's plant construction, A prompt System is urgently needed to carries prevention and control of hazards associated with work related tasks and activities. This study is aimed to develop efficient and reliable safety management program to identify control measures for high risk activities by choosing and conducting proper risk assessment methodology that addresses Risk Priority Number(RPN) of adverse effects.

• 품질경영학회지
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• 제50권1호
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• pp.125-138
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• 2022

Purpose: Failure Mode and Effect Analysis (FMEA) is a widely utilized technique to measure product reliability by identifying potential failure modes. Even though FMEA techniques have been studied, the form of Risk Priority Number (RPN) used to evaluate risk priority in FMEA is still questionable because of its shortcomings. In this study, we suggest common RPN(cRPN) to resolve shortcomings of the traditional RPN and show the extensibility of cRPN. Methods: We suggest cRPN which is based on Cobb-Douglas production function, and represent the various application on weighting risk factors, weighted RPN in a mathematical way, and show the possibility of statistical approach. We also conduct numerical study to examine the difference of the traditional RPN and cRPN as well as the potential application from the analysis on marginal effects of each risk factor. Results: cRPN successfully integrates previously suggested approaches especially on the relative importance of risk factors and weighting RPN. Moreover, we analyze the effect of corrective actions in terms of econometric analysis using cRPN. Since cRPN is rely on the reliable mathematical model, there would be numerous applications using cRPN such as smart factory based on A.I. techniques. Conclusion: We propose a reliable mathematical model of RPN based on Cobb-Douglas production function. Our suggested model, cRPN, resolves various shortcomings such as consideration of the relative importance, the effect of combinations among risk factors. In addition, by adopting a reliable mathematical model, quantitative approaches are expected to be applied using cRPN. We find that cRPN can be utilized to the field of industry because it is able to be applied without modifying the entire systems or the conventional actions.

• 한국건설관리학회논문집
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• 제23권6호
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• pp.101-110
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• 2022

최근 세계 건설시장은 2025년까지 연 평균 4.8%씩 성장할 것으로 예상하고 있으며, 이에 따른 해외건설 리스크도 증가할 것으로 전망하고 있다. 특히, 국내 건설업체들은 EPC(Engineering, Procurement, Construction)/Turnkey 사업에 집중적으로 참여하였지만, 계약적 리스크에 대응하지 못한 결과, 2013년부터 수조원대의 해외사업 손실을 입은 경험이 있다. 그럼에도 불구하고, 지금까지 EPC/Turnkey의 계약적 핵심 리스크 세부조항 도출에 대한 연구는 많지 않았다. 따라서 본 연구에서는 국제컨설팅엔지니어링연맹(FIDIC)에서 발행한 2017년 Silver Book 계약조건을 대상으로 핵심 리스크 세부조항을 연구하였다. 이를 위해서 국제건설계약 경험이 10년 이상인 30인의 전문가를 패널로 구성하여 FIDIC Silver Book 21개 조항 170개 세부조항을 델파이 설문조사를 실시하여 62개의 주요 리스크 세부조항을 도출하였다. 또한, 최종적으로 FMEA(Failure Mode and Effect Analysis)기법을 활용하여 RPN(Risk Priority Number)을 산정하였으며, Critical Risk 범위에 속하는 25개의 핵심 리스크 세부조항을 도출하였다. 본 연구 결과를 통하여 실무관점에서는 해외건설사업에서 입찰 및 계약체결 단계에서 주의 깊게 검토해야 할 계약조항들에 대해 참조할 수 있게 해주고, 학문관점에서는 해외건설 EPC/Turnkey 사업에서 사용되는 계약분야에 대해 어떤 방식으로 연구해야 할지의 방향성과 기초적 지식을 제공하고 있다.

• Industrial Engineering and Management Systems
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• 제14권4호
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• pp.379-391
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• 2015

Several risk assessment techniques have been presented and investigated in previous research, focusing mainly on the failure mode and effect analysis (FMEA). FMEA can be employed to determine where failures can occur within industrial systems and to assess the impact of such failures. This research proposes a novel methodology for hazard analysis and risk assessments that integrates FMEA with the bow-tie model. The proposed method has been applied and evaluated in a real industrial process, illustrating the effectiveness of the proposed method. Specifically, the bowtie diagram of the critical equipment in the adopted plant in the case study was built. Safety critical barriers are identified and each of these is assigned to industrial process with an individual responsible. The detection rating to the failure mode and the values of risk priority number (RPN) are calculated. The analysis shows the high values of RPN are 500 and 490 in this process. A global corrective actions are suggested to improve the RPN measure. Further managerial insights have been provided.