• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1210-1216
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• 2018

Site or multi-unit (MU) risk assessment has been a major issue in the field of nuclear safety study since the Fukushima accident in 2011. There have been few methods or experiences for MU risk assessment because the Fukushima accident was the first real MU accident and before the accident, there was little expectation of the possibility that an MU accident will occur. In addition to the lack of experience of MU risk assessment, since an MU nuclear power plant site is usually very complex to analyze as a whole, it was considered that a systematic method such as probabilistic safety assessment (PSA) is difficult to apply to MU risk assessment. This paper proposes a new MU risk assessment methodology by using the conventional PSA methodology which is widely used in nuclear power plant risk assessment. The logical failure structure of a site with multiple units is suggested from the definition of site risk, and a decomposition method is applied to identify specific MU failure scenarios.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.286-294
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• 2017

The events at the Fukushima Daiichi Nuclear Power Station in March 2011 point out, among other matters, that concurrent accidents at multiple units of a site can occur in reality. Although site risk has been deterministically considered to some extent in nuclear power plant siting and design, potential occurrence of multi-unit accident sequences at a site was not investigated in sufficient detail thus far in the nuclear power community. Therefore, there is considerable worldwide interest and research effort directed toward multi-unit site risk assessment, especially in the countries with high-density nuclear-power-plant sites such as Korea. As the technique of probabilistic safety assessment (PSA) has been successfully applied to evaluate the risk associated with operation of nuclear power plants in the past several decades, the PSA having primarily focused on single-unit risks is now being extended to the multi-unit PSA. In this paper we first characterize the site risk with explicit consideration of the risk associated with spent fuel pools as well as the reactor risks. The status of multi-unit risk assessment is discussed next, followed by a description of the emerging issues relevant to the multi-unit risk evaluation from a practical standpoint.

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1199-1209
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• 2018

After the Fukushima-Daiichi accident in 2011, the multi-unit risk, i.e., the risk due to several nuclear power plants (NPPs) in a site has become an important issue in several countries such as Korea, Canada, and China. However, the multi-unit risk has been discussed for a long time in the nuclear community before the Fukushima-Daiichi nuclear accident occurred. The regulatory authorities around the world and the international organizations had proposed requirements or guidelines to reduce the multi-unit risk. The concerns regarding the multi-unit risk can be summarized in the following three questions: How much the accident of an NPP in a site affects the safety of other NPPs in the same site? What is the total risk of a site with many NPPs? Will the risk of the simultaneous accidents at several NPPs in a site such as the Fukushima Daiichi accident be low enough? The multi-unit risk assessment (MURA) in an integrated framework is a practical approach to obtain the answers for the above questions. Even though there were few studies to assess the multi-unit risk before the Fukushima-Daiichi nuclear accident, there are still several issues to be resolved to perform the complete MURA. This article aims to provide an overview of the multi-unit risk issues and its assessment. We discuss the several critical issues in the current MURA to get useful insights regarding the multi-unit risk with the current state art of probabilistic safety assessment (PSA) technologies. Also, the qualitative answers for the above questions are addressed.

• 한국건설관리학회논문집
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• 제10권6호
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• pp.117-126
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• 2009

건설 산업에 내재된 위험은 작업환경, 작업의 종류, 작업자의 특성 등이 결합되어 발생한다. 건설 현장의 가변적이며 유동적인 특성을 고려한다면 동일 공종이라도 내재된 특성들의 조합에 따라 위험의 크기가 다르게 나타날 수 있다. 하지만 기존의 안전 관리 방식은 이러한 건설업의 특성을 반영하지 못한 체 타산업과 유사한 안전 관리를 수행하고 있다. 이에 본 연구는 건설현장의 다양한 위험 요소를 고려한 위험도 산정 방법을 제시하기 위해 선행연구 분석 및 설문을 통해 위험 영향 요소를 도출하고 가중치 체계를 구축하였다. 그리고 빈도와 강도 기반의 공종별 위험도를 구하였다. 위험 영향 요소와 공종별 위험도를 결합하여 건설 현장의 상황에 맞는 위험도 산정 방법을 마련하였다. 이로써 건설 현장의 특성을 고려한 위험도를 구할 수 있으며, 위험도를 바탕으로 보다 효과적인 안전관리활동을 펼칠 수 있을 것이다. 따라서 본 연구는 위험 영향 요소들을 고려하여 현장 특성을 반영한 위험도를 산정하였다는데 그 의미가 있다.

• 한국방재학회 논문집
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• 제5권4호
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• pp.9-15
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• 2005

본 연구는 도심지에 위치한 LPG 충전소를 연구범위로 하여 공간정보의 활용이 가장 많이 요구되는 안전관리 분야의 업무를 중심으로 공간정보를 효율적으로 구축 활용하기 위하여 데이터베이스를 중심으로 위험관리정보 시스템을 개발하였다. 이를 바탕으로 정량적 위험성 평가의 자동화를 통해 나타난 위험성을 실시간에 제어하기 위한 필요조건을 표준화하여 기초 정보자료로 구축, 이를 지리정보기능과 연동하여 LPG 충전소의 안전검사의 효율화, 사전 위험성 평가, 사고대응 판단의 효과적인 의사결정을 유도 할 수 있는 기반을 제공한다. 위험관리정보시스템(RMIS, Risk Management Information System) 개발절차는 다음과 같다. 첫째, 도심지에 위치한 LPG 충전소 위험성 평가를 수행함에 있어서 기본적인 데이터인 부지내(On-site) 관련 자료와 부지 외(Off-site) 관련 자료를 관계형 데이터베이스(RDB, Relational Database)로 개발하였다. 둘째, Visual Basic을 이용하여 사용자가 효과적으로 위험을 관리 제어 할 수 있는 위험관리 통합 데이터베이스 시스템 개발하였다. 셋째, 위험관리 통합 데이터베이스 시스템과 지리정보시스템에 연동을 통한 의사결정 방안 제시하였다. 위험관리정보시스템(RMIS) 프로그램을 개발을 통하여 다음과 같은 결과를 도출하였다. 첫째, 위험관리 데이터 이용하여 사용자와 검사자가 효과적으로 위험을 사전관리 할 수 있는 공유정보를 구축하였다. 둘째, 위험 관리를 부지 내와 부지 외로 나누어 관리함으로서 시설 내부 뿐 만 아니라 시설외부에 미치는 영향을 모두 고려하여 구축하므로 서, 중대사고에 대응 할 수 있는 종합적인 안전관리 기반을 조성하였다. 셋째, 사용자 인터페이스를 바탕으로 비상사태 발생시에 신속하고 정확한 의사결정을 할 수 있는 기반을 조성하였다.

• 한국안전학회지
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• 제27권4호
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• pp.62-67
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• 2012

Risk Assessment, a basis of health and safety management system, is an calamity prevention activity which regularly measure the level of a risk to passively improve potential hazard. A problem, the assessment not being improved to be applied to the construction work site where requires diversity and complexity, causes the assessment to be inefficient to bring quality results. A study on the investigates and compares the surveyed degree of recognitions of workers who works in companies executing the risk assessment By the investigation and comparison, it is expected to bring the better solution for early and efficient application for those companies which are not taking the risk assessment.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2012년 춘계학술대회
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• pp.1-11
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• 2012

Risk Assessment, a basis of health and safety management system, is an calamity prevention activity which regularly measure the level of a risk to passively improve potential hazard. A problem, the assessment not being improved to be applied to the construction work site where requires diversity and complexity, causes the assessment to be inefficient to bring quality results. A study on the investigates and compares the surveyed degree of recognitions of workers who works in companies executing the risk assessment By the investigation and comparison, it is expected to bring the better solution for early and efficient application for those companies which are not taking the risk assessment.

• 기본간호학회지
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• 제21권2호
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• pp.151-161
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• 2014

Purpose: The purpose of this study was to identify the risk factors that influence surgical site infections after surgery. Methods: This study was a retrospective research utilizing Electronic Medical Records. Data collection targeted 4,510 adult patients who had 8 different kinds of surgery (gastric surgery, colon surgery, laparoscopic cholecystectomy, hip & knee replacement, hysterectomy, cesarean section, cardiac surgery) in 4 medical care departments, at one general hospital between January 2006 and December 2011. Multivariate logistic regression analyses were used to identify the risk factors affecting surgical site infections after surgery. Results: Risk factors for increased surgical site infection following surgery were confirmed to be age (OR=1.59, p<.001), BMI (Body Mass Index)(OR=1.25, p=.034), year of operation (OR=2.45, p<.001), length of operation (OR=3.06, p<.001), ASA (American Society of Anesthesiology) score (OR=1.36, p=.025), classification of antibiotic used (OR=2.77, p<.001), duration of the prophylactic antibiotics use (OR=1.85, p<.001), and interaction between classification of antibiotic used and duration of the prophylactic antibiotics use (OR=1.90, p=.016). Conclusions: Results suggest that risk factors affecting surgical site infections should be monitored before surgery. The results of this study should contribute to establishing effective infection management measures and implementing surveillance systems for patients who have actual risk factors.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1231-1236
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• 2009

Many work-related risk factors can cause construction site hazards. Therefore, safety management begins with measuring the magnitude of risk involved in a project. This study proposes a methodology for risk assessment of major trades at a particular construction site. To assess risk, this methodology integrates hazard severity and frequency, and their magnitude is calculated based on actual work-site hazards. This methodology also considers the influence factors that affect the frequency of work-related hazards. To select the appropriate influence factors, a two step approach is deployed. First, the predominant factors are identified through a literature review. Second, a selective process filters out the influence factors that are difficult to analyze quantitatively, and these extracted factors are weighted using expert surveys. Finally, the factors are combined and a quantitative risk assessment methodology is proposed.

• 한국안전학회지
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• 제28권4호
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• pp.72-80
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• 2013

Accident prevention plan it a construction site should be analyzed and made with risk evaluation and management, from recent year, in Korea. Accidents occurred in construction site are related to all parties such as owner, main and subcontractor, labour. But analyzing some relationship between main and subcontractor is very important to estimate what risk between then are existed in a site. There are some different aspects concerning with risk management between them. Everywork has its own risk in there, This is the reason why everywork which are made by subcontractor himself should be evaluated for risk level. And main contractor should provide for subcontractor to prevent each risk at the work, all the time.