• 대한안전경영과학회지
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• 제14권1호
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• pp.225-233
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• 2012

The research discusses interrelationship of structural and reliability importance measures which used in the probabilistic safety assessment. The most frequently used component importance measures, such as Birnbaum's Importance (BI), Risk Reduction (RR), Risk Reduction Worth (RRW), RA (Risk Achievement), Risk Achievement Worth (RAW), Fussel Vesely (FV) and Critically Importance (CI) can be derived from two structure importance measures that are developed based on the size and the number of Minimal Path Set (MPS) and Minimal Cut Set (MCS). In order to show an effectiveness of importance measures which is developed in this paper, the three representative functional structures, such as series-parallel, k out of n and bridge are used to compare with Birnbaum's Importance measure. In addition, the study presents the implementation examples of Total Productive Maintenance (TPM) metrics and alternating renewal process models with exponential distribution to calculate the availability and unavailability of component facility for improving system performances. System state structure functions in terms of component states can be converted into the system availability (unavailability) functions by substituting the component reliabilities (unavailabilities) for the component states. The applicable examples are presented in order to help the understanding of practitioners.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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• pp.838-843
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• 1998

Risk importance measures are widely wed to rank risk contributors in risk-based applications. Typically, Fussell-Vesely (F-V) importance and risk achievement worth (RAW) are used in the component importance raking for the reliability centered maintenance (RCM) analysis of safety system in nuclear power plants (NPPs). This study was performed as part of feasibility study on RCM for domestic NPPs, which is focused on the component importance ranking approach the maintenance recommendation. The approach of modulizing faulting tree basic events was applied in the simplification process of the PSA model and the validity of the approach was evaluated As a result of the case study, this paper included the importance and the maintenance recommendations for the safety-related equipments associated with safety injection and containment spray in large loss of coolant accident sequences.

• 대한산업공학회지
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• 제33권1호
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• pp.61-69
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• 2007

In a large complex system, maintenance priorities for the failed components are important to maintain the sys-tern reliability at required level. Commonly used methods of determining maintenance priorities are based onranking the failed components by using reliability importance measures such as Birnbaum reliability importance,risk achievement worth and F-V importance, etc. In the preceding works, maintenance priorities for the failedcomponents are determined by using such existing measures, In this study, a new method of determining main-tenance priorities, which utilizes the joint reliability importance is proposed. By investigating the sign of thejoint reliability importance, maintenance priorities obtained by the existing methods are adjusted to yield new re-vised priorities. The revised maintenance priorities are shown to be more effective than the existing ones fromthe standpoint of the speed of system recovery, Effectiveness of the proposed method is illustrated by numericalexamples.

• 한국화재소방학회논문지
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• 제18권3호
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• pp.57-73
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• 2004

Pilot LNG Tank에서 LNG가 누출되어 화재가 발생할 경우의 정량적 안전성 평가를 고장수목법을 이용하여 4가지 형태의 주요 시나리오를 도출하고 이에 대한 분석을 수행하였다. 첫째 방출관에서 누출할 경우에 특정 Low Flammable Limit(LFL)반경은 형성하지 않았으며, 둘째는 탱크파손으로 인한 LNG 유출이라는 최악의 시나리오 분석을 수행하였고, 그 결과를 살펴보면 총 누출량이 같더라도 시간에 따라 여러 가지 확산범위가 나타남을 확인할 수 있었다. 셋째는 inlet/outlet파이프의 손상으로 인한 누출로 10달과 타분 두 경우에 대해 분석하였으나, 각각의 경우 LFL의 반경은 큰 차이를 보이지 않았다. 따라서, 이와 같은 LNG누출 사고의 경우 초기 방출량의 크기가 확산의 주요 인자임을 알 수 있었다. 넷째는 방류둑에서 LNG배관이 파손될 경우 LFL의 크기를 산출하였다. 한편 복사열 및 불꽃의 크기에 대한 피해결과 분석을 동시에 수행하였다.

• 대한가정학회지
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• 제41권8호
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• pp.1-17
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• 2003

The purpose of this study is to understand North Korean female defectors' experiences in China. 13 female defectors were interviewed. Before they extricated from North Korea, they expected to make money to survive with their family in North Korea. But it couldn't be done because they didn't have legal status in China. They were at the risk of exposing to traffickers in females and of repatriation to North Korea. Surviving in China, they realized they were “Chosun(North Korean) females”; it meant they were in extremely poor and were sold by traffickers. It made them put to shame and be hurt their pride as a Chosun national identity. On the other hand, they realized they had narrow experiences and a limited outlook on international issues. They made themselves accustomed to freedom from the Chinese Revolution ; some of them experienced achievement. In general, they were satisfied with physical needs, but lacks of safety and worth in life. Even though, they couldn't return to North Korea because they were afraid of being punished by their government, and of striking their family a fatal blow in their successful lives of the society.

• STI Policy Review
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• 제5권1호
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• pp.75-97
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• 2014

Entrepreneurial financing, such as publicly initiated venture capital or grant schemes, serves as an important policy instrument that aims to bridge the financing gap facing young, innovative businesses, a gap that is mainly due to higher risk and growing uncertainty, and to strategically promote the creation of new ventures through the revitalization of their venture capital industries. This study examines public venture capital initiatives in Australia, Canada, and Sweden, and discovered that all three countries actively foster their venture capital industry through the formation of funds or the provision of tax incentives. It is notable that the majority of financing initiatives heavily depend on supply-side measures rather than demand-driven policies that focus on stimulating private investment in technological innovations and discoveries. This paper discusses in-depth the policy impact of public financing initiatives and their subsequent side-effects raised in the process such as overlapping in funding structure across the country, lack of monitoring and evaluation for feedback, fragmentation across the government ministries and agencies, and competition with the private sector, which may cause inefficiency as a result of public intervention. Financial constraints may arise for many reasons, partly resulting from the lack of investment readiness of young entrepreneurs. This signals a policy shift towards the creation of market-driven demand away from the traditional supply-push approach, and is a grand challenge to policymakers in entrepreneurial financing. Attention is leaning towards the efficiency and effectiveness of these public-financing initiatives in terms of their policy roles. It is worth noting that policy should focus on generating synergy so available resources can be channeled into the early, risky stage of new ventures, working as facilitator to the achievement of an intended policy goal.

• 디지털융복합연구
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• 제10권9호
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• pp.239-251
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• 2012

이 연구의 목적은 소상공인들의 생존율에 영향을 미치는 창업초기 성과를 높일 수 있는 영향요인들을 탐색적으로 연구하여 소상공인 성공창업을 위한 정책과 방안을 모색하고자 하였다. 소상공인이 인지하는 창업성과(매출액, 순이익, 결과기대감)를 측정하기 위해서 독립변수로 창업가특성(경험, 심리적특성), 창업 준비과정, 매개변수로 자기효능감을 측정하였다. 설문대상은 창업초기 소상공인 427명으로부터 구조화된 자기기입식 질문지를 수집하고, SPSS 18.0 통계프로그램을 활용하여 다중회귀분석기법을 사용하였다. 연구결과는 업종경험, 성취욕구, 위험감수성향, 창업 준비기간은 자기효능감에 유의미한 영향을 미치고, 실패경험과 자기자본비율이 매출액과 순이익에 유의미한 영향을 미쳤으며, 통제위치는 매개변수인 자기효능감을 통해 결과기대감에 유의미한 영향을 미치는 것으로 나타났다. 창업가 특성과 창업 준비과정에 따라서 소상공인의 자기효능감과 창업성과가 달라진다는 것이 발견되었다. 이러한 연구결과를 토대로 이론적 실천적 함의를 논의 하였고, 연구의 문제점 및 향후 정책, 연구를 위한 제언을 제시하였다.