• 한국안전학회지
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• 제34권5호
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• pp.167-174
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• 2019

Compared to a single nuclear power plant (NPP) risk, the commonalities existing in the multiple NPPs attribute the characteristics of the multi-unit risk. If there is no commonality among the multiple NPPs, there will be no dependency among the risks of multiple NPPs. Therefore, understanding the commonality causing multi-unit events is essential to assessing the multi-unit risk, and identifying the characteristics of the multi-unit risk is necessary not only to select the scope and method for the multi-unit risk assessment, but also to analyze the data of the multi-unit events. In order to develop Korea-specific multi-unit risk assessment technology, we analyze the multi-unit commonalities included in the operational experiences of domestic NPPs. We identified 58 cases of multi-unit events through detailed review of domestic nuclear power plant event reports over the past 10 years, and the multi-unit events were classified into six commonalities to identify Korea-specific characteristics of multi-unit events. The identified characteristics can be used to understand and manage domestic multi-unit risks. It can also be used as a basis for modeling multi-unit events for multi-unit risk assessment.

• 응용통계연구
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• 제25권3호
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• pp.435-446
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• 2012

Epidemiologic studies frequently try to estimate the impact of a specific risk factor. The risk difference and the risk ratio are generally useful measurements for this purpose. When using such measurements for rare events, the standard approaches based on the normal approximation may fail, in particular when no events are observed. In this paper, we discuss and evaluate several existing methods to construct confidence intervals around risk differences and risk ratios using Monte-Carlo simulations when the disease of interest is rare. The results in this paper provide guidance how to construct interval estimates of the risk differences and the risk ratios when no events are detected.

• 한국건설관리학회논문집
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• 제23권3호
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• pp.25-35
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• 2022

본 연구의 목적은 활주로 건설공사에서 수집된 공사비 내역서, 설계변경 자료 등을 근거로 발생된 위험사건(위험항목)으로 인하여 변동된 공사금액을 산정하고 위험사건이 발생하게 된 원인에 따라 사업참여기관별로 손실비용을 분석하는 것이다. 본 연구를 수행한 결과, 위험사건은 12건이며, 증액된 총 공사금액은 726백만원으로 발주기관이 부담하여야 하는 금액은 약 52.57%, 건설사는 약 47.43%로 산정되었다. 또한, 계약금액의 직접공사비 149억원 대비 증액된 공사금액은 약 4.86%이며, 토공사로 분류된 위험사건에 따라 증액된 공사금액은 토공사의 직접공사비 대비 약 5.29% 그리고 건축공사로 분류된 위험사건에 따라 증액된 공사금액은 건축공사의 직접공사비 대비 약 4.04%에 해당하는 것으로 도출되었다.

• 한국건설관리학회논문집
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• 제4권2호
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• pp.109-117
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• 2003

건설사업은 그 규모와 복잡성으로 인하여 다른 산업에 비해 위험에 대한 노출수위가 크고, 그 형태도 다양하다. 따라서, 건설사업에서 위험을 인지하고 대응하는 일련의 위험관리 과정은 정확하고 체계적으로 수행되어야 한다. 위험관리 과정에서 위험인지 단계는 다양한 위험요인의 인지와 그 위험의 성격을 규정하는 단계이고. 이러한 위험인지 단계에서 위험분류체계는 사업에 내재된 다양한 위험을 인지하게 해주는 유용한 도구이다. 본 연구에서는 기존 위험분류체계의 문제점을 개선하고 재정립함으로서, 실질적인 건설사업에서 위험인지 도구로서 활용될 수 있는 사업단계별, 계약주체별 체크리스트를 제안하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1518-1523
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• 2008

Train collision and derailment are types of accident with low probability of occurrence, but they could lead to disastrous consequences including loss of lives and properties. The development of the risk assessment model has been called upon to predict and assess the risk for a long time. Nevertheless, the risk assessment model is recently introduced to the railway system in Korea. The classification of the hazardous events and causes is the commencement of the risk assessment model. In previous researches related to the classification, the hazardous events and causes were classified by centering the results. That classification was simple, but might not show the root cause of the hazardous events. This study has classified the train collision and derailment based on the relevant hazardous event including faults of the train related the accidents, and investigates the causes related to the hazardous events. For the risk assessment model, FTA (fault tree analysis) and ETA (event tree analysis) methods are introduced to assess the risk.

• 대한인간공학회지
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• 제22권1호
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• pp.81-94
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• 2003

The British railway safety research group has developed a risk assessment model for the railway infrastructure and major railway accidents. The major hazardous factors of the railway infrastructure were identified and classified in the model. The frequency rates of critical top events were predicted by the fault tree analysis method using failure data of the railway system components and ratings of railway maintenance experts, The consequences of critical top events were predicted by the event tree analysis method. They classified the Joss of accident due to railway system into personal. commercial and environmental damages. They also classified 110 hazardous event due to railway system into three categories. train accident. movement accident and non-movement accident. The risk assessment model of the British railway system has been designed to take full account of both the high frequency low consequence type events (events occurring routinely for which there is significant quantity of recorded data) and the low frequency high consequence events (events occurring rarely for which there is little recorded data). The results for each hazardous event were presented in terms of the frequency of occurrence (number of events/year) and the risk (number of equivalent fatalities per year).

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2403-2407
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• 2015

Background: Very few analytical studies are available on any association between stressful life events (SLE) and colorectal cancer (CRC), at least in Iran. The aim of this case control study was to determine the association between stressful life events (SLE) and colorectal cancer. Materials and Methods: This study was conducted in four hospital colonoscopy units in Tabriz city of Iran including 414 participants aged 40-75 years: 207 cases with CRC confirmed by pathology and colonoscopy findings and 207 controls free of neoplastic conditions were selected (from the same hospitals at the same period for the cases and after matching for age and sex). Stressful life events were assessed using a 43-item Holmes and Rahe Life Events Questionnaire. Multivariate logistic regression was used to estimate adjusted odds ratios for SLE and risk of CRC. Results: The stressful life event mean score in the case group was 141.3, in contrast to 63.8 in the control group (p<0.011). After adjusting for confounders, death of dear ones increased the risk of CRC (OR: 2.49; 95%CI: 1.41-5.13). Other types of stressful life events (family and husband disputes, serious occupational problems, unemployment of > 6 months, and Serious financial problems) were also associated with CRC, but without statistical significance. Conclusions: According to our findings, it seems that SLE may increase the risk of CRC.

• Journal of Construction Engineering and Project Management
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• 제6권2호
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• pp.24-29
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• 2016

This paper elaborates the significance of scenario planning in risk management, and presents an integrated approach which takes into account the 'Risk Events' derived from scenario planning for risk prioritisation. This research integrates scenario planning with Risk Failure Mode and Effect Analysis (RFMEA) through examples from construction litigations of project schedule and cost overrun cases as a simplified approach to project risk management. The proposed methodology incorporates scenarios developed from realistic events of dispute and arbitration cases from construction projects, and thereby increasing potential to foresee risks and their effects well in advance. The results from this methodology shall be validated against outcome of survey study conducted by KPMG-PMI (2013) on project schedule and cost overruns that was based on Ministry of Statistics and Programme Implementation (MoSPI) Project Monitoring data for 2012-13.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.380-386
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• 2017

Fennovoima's nuclear power plant, Hanhikivi 1, $Pyh{\ddot{a}}joki$, Finland, is currently in design phase, and its construction is scheduled to begin in 2018 and electricity production in 2024. The objective of this paper is to produce a preliminary list of safety-significant external event combinations including preliminary probability estimates, to be used in the probabilistic risk assessment of Hanhikivi 1 plant. Starting from the list of relevant single events, the relevant event combinations are identified based on seasonal variation, preconditions related to different events, and dependencies (fundamental and cascade type) between events. Using this method yields 30 relevant event combinations of two events for the Hanhikivi site. The preliminary probability of each combination is evaluated, and event combinations with extremely low probability are excluded from further analysis. Event combinations of three or more events are identified by adding possible events to the remaining combinations of two events. Finally, 10 relevant combinations of two events and three relevant combinations of three events remain. The results shall be considered preliminary and will be updated after evaluating more detailed effects of different events on plant safety.

• Journal of Preventive Medicine and Public Health
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• 제34권1호
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• pp.35-40
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• 2001

Objectives : To elucidate the transient effects on the risk of occupational injuries as acute events and establish so alternative proposal. Methods : The study population comprised a total of 302 workers randomly selected from applications for occupational injury compensation reported to the Inchon local labor office from January 1. 1999 to December 31. A case-crossover design, where each case serves its own control, was applied to this study. Through a telephone interview, workers provided useful data concerning five job related stressful events such as company transfer, work load change, overtime work, exchange duty, and work-part transfer. They were asked whether there were stressful events within a week of the occurrence of injury and the degree of stress. Exposure status from one year prior was used as control information. In the end, the data provided by 158 of selected persons was used for the analysis based on the quality of the data provided by the participants. A conditional logistic regression was used to discover the transient effects on the risk of occupational injuries as acute events. Results : The effects a company transfer and work load change on occupational injury was statistically significant on the risk of occupational Injuries as an acute event(RR=5.5, 95% CI=2.501-12.428; RR=3.1, 95% CI=1.963-5.017, respectively). Other stressful events were found to elevate the risk factor for the occurrence of occupational jujury, but were not significant. Conclusions : Our results suggested that transient stressful events elevated the risk factor for the occurrence of occupational injury.