• Journal of the Korean Institute of Gas
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• v.5 no.2 s.14
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• pp.9-13
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• 2001

A complete spectrum of risk assessment including qualitative and quantitative approaches were performed for the POSCO's Batch Annealing Furnace (BAF) gas systems. The purpose of BAF is to enhance the quality of steel by annealing it with either hydrogen/nitrogen mixture gas or pure hydrogen gas. Number of gas leak scenarios were identified to generate frequency of their occurrences. With the hypothetical accident scenarios given, fire/explosion impact studies were performed to estimate magnitude of significant consequences. Several different indices were also presented from which practical safety improvement action items could be established.

• Proceedings of the Safety Management and Science Conference
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• 2003.11a
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• pp.15-20
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• 2003

본 연구에서는 계절별 기후인자를 고려하여 정성적 및 정량적 위험성 평가를 실시하여 사고 시나리오를 설정하였고, 비용-편익분석을 실시하여 사고 시나리오별 안전관리 비의 효율을 분석하였다. 그 결과, 최악의 시나리오는 비정상조업에서 유지보수 오류이었고, 가능성 있는 시나리오는 HAZOP 구간#4에서 발생되는 가스 누출사고이었으며, 각 사고 시나리오에서 전체 안전관리 투자비에 대한 편익/비용은 0.043과 0.13이었다. 이때 각 사고 시나리오에서 비용 효과적인 안전관리 항목을 평가할 수 있었다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.6-7
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• 2017

무인선박의 출현 및 운항 시기가 도래하는 시점에서, 항해사들의 경험적, 정성적 방법으로 항로를 설정하던 기존의 방식이 아니라 정량적 항로 결정 방식 필요성이 제기된다. 본 연구에서는 위험물(HNS) 적재선의 해상교통사고 리스크 기반의 침로 설정을 통해 실시간 데이터 활용에 따라 변화 추정 및 인적 오류를 최소화하여 무인선박 운항 시 활용 가능한 항로 설정 기법을 제안하였다. 항로 주변의 정적 위험(Static Hazard)을 기반한 리스크 평가 방법을 제시하고, Contour map으로 시각화 통해 무인선박뿐 아니라 현존하는 선박에도 적용 가능하여, 사용자 결정에 따라 리스크 기반으로 침로 설정 통해 선박 운항 효율성 및 안전성 확보에 기여할 것으로 기대된다. 본 연구 내용을 토대로 정적 위험뿐 만아니라 선박을 포함한 동적 위험을 반영한 실시간 리스크 기반 항로 설정까지 확장하기 위한 연구가 요구된다.

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.81-86
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• 1997

This study is to estimate the possibility of accident in chemical plants from the analysis of system component which affects the occurrence of top event. Among the various risk assessment techniques, the Fault Tree Analysis which approaches deductively on the route of accident development was used in this study. By gate-by-gate method and minimal cut set, the qualitative and quantitative risk assessment for hazards in plants was performed. The probability of occurrence and frequency of top event was calculated from failure or reliability data of system components at stage of the quantitative risk assessment. In conclusion, the probability of accident was estimated according to logic pattern based on the Fault Tree Analysis. And the failure path which mostly influences on the occurrence of top event was found from Importance Analysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.90-98
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• 2021

Since 2017, the Occupational Safety and Health Act has been fully applied to school food services, and risk assessments have been implemented since 2019. The introduction was slow compared to other industries and was evaluated by non-professional nutritionists, so there was a limit to establishing the system. All schools under the Seoul Metropolitan Office of Education apply the KRAS every year in accordance with the OSH Act for school foodservice and a notice from the Ministry of Employment and Labor. A risk assessment is applied according to legal regulations. On the other hand, the effectiveness of risk assessment has been questioned because the frequency and intensity criteria of the risk are qualitative and subjective. Based on the accident statistics of catering workers, the frequency and intensity criteria of risk were presented quantitatively and objectively, and a risk assessment was conducted by applying a new calculation standard for some work during the catering service and compared with current risk assessment results. The risk was increased, and the improved effectiveness was confirmed by the specific suggestions for improvement. Thus, the pilot evaluation for the entire food service should be expanded, and the feasibility confirmed. The pilot evaluation should be applied to all schools to enhance the effectiveness and operability of the risk assessment.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1195-1196
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• 2007

최근 들어 컴퓨터화된 열차제어시스템의 사용이 증가함에 따라서 장치들의 고장이 대규모 인명피해나 경제적 손실과 직결되는 경우가 발생하고 있다. 따라서 열차제어시스템의 안전성 확보를 위한 절차를 수행하는 체계인 안전성 활동을 시스템의 수명주기 전반에 걸쳐 진행하여야 한다. 본 논문에서는 안전성 활동 중에서 위험도 분석 및 평가를 위한 방법에 대해 알아볼 것이며, 그 중에 최적화된 새로운 방식을 한 가지 제안하고자 한다. 정성적인 분석과 정량적인 분석의 특징을 혼합하여 절충한 제안하고자 하는 방식이 Best-Practice(BP) 위험도 분석 방식이다.

• Journal of Korean Society of societal Security
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• v.1 no.1
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• pp.53-62
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• 2008

Recently, the potential risks of tank lorry transportation from the petrochemical plant have been increasing, so the research was performed to build up the evaluation criterion of the transportation safety, as well as aggressive risk+assessment of a variety of chemical materials. This research was applied to the Maximum Credible Accident Analysis technique and modeled on the risk management of chemical transportation using the following four steps for risk evaluation, firstly the comparison of representative fype and standard of hand ling chemical materials transported by tank vehicles secondly, specific classification of potential hazards thirdly, grasp and recognition of virtual accident scenario at last, the risk evaluation of virtual accident scenario(qualitative/quantitative - chemical release modeling).

• Journal of the Korean Institute of Gas
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• v.9 no.4 s.29
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• pp.44-49
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• 2005

In this study, a process safety evaluation is implemented, in which the process hazards are investigated systematically about hydrogen production plants. Be used qualitative Safety management method such as HAZOP and FMEA. Were analysed potential hazards (human errors or operating failures of every processing steps) about parameters that flow, pressure, temperature of hydrogen production plants through HAZOP that making deviations applied signified guide words. Analysed to using FMEA mainly about bad components or troubles that equipments breakdown and malfunction in facilities and then propose its influences, and counterproposal.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.10
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• pp.1291-1296
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• 2013

Risk-based inspection (RBI) is a well-known method that is used to optimize inspection activities based on risk analysis in order to identify the high-risk components of major facilities such as power plants. RBI, when implemented and maintained properly, improves plant reliability and safety while reducing unplanned outages and repair costs. Risk is given by the product of the probability of failure (POF) and the consequence of failure (COF). A semi-quantitative method is generally used for risk assessment. Semi-quantitative risk assessment complements the low accuracy of qualitative risk assessment and the high expense and long calculation time of quantitative risk assessment. The first step of RBI is to identify important failure modes and causes in the equipment. Once these are defined, the POF and COF can be assessed for each failure. During POF and COF assessment, an effective inspection method and range can be easily found. In this paper, the calculation of the POF is improved for accurate risk assessment. A modified semi-quantitative risk assessment was carried out for boiler facilities of thermal power plants, and the next maintenance schedules for the equipment were decided.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.2
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• pp.238-247
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• 2023

Liquefied petroleum gas (LPG) is an attractive fuel for ships considering its current technology and economic viability. However, safety guidelines for LPG-fueled ships are still under development, and there have been no cases of applying LPG propulsion systems to small and medium-sized ships in Korea. The purpose of this study was to perform an objective risk assessment for the first marine LPG engine system and propose safe operational standards. First, hazard and operability (HAZOP) analysis was used to divide the engine system into five nodes, and 58 hazards were identified. To compensate for the subjectivity of qualitative evaluation using HAZOP analysis, fuzzy set theory was used, and additional risk factors, such as detectability and sensitivity, were included to compare the relative weights of the risk factors using a fuzzy analytical hierarchy process. As a result, among the five risk factors, those with a major impact on risk were determined to be the frequency and severity. Finally, the fuzzy technique for order of preference by similarity to ideal solution (TOPSIS) was applied to select the risk rank more precisely by considering the weights of the risk factors. The risk level was divided into 47 groups, and the major hazard during the operation of the engine system was found through the analysis to be gas leakage during maintenance of the LPG supply line. The technique proposed can be applied to various facilities, such as LPG supply systems, and can be utilized as a standard procedure for risk assessment in developing safety standards for LPG-powered ships.