• 대한핵의학회지
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• 제26권1호
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• pp.8-13
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• 1992

Low doses of ionizing radiation from external or internal sources cause heterogeneous distribution of energy deposition events in the exposed biological system. With the cell being the individual element of the tissue system, the fraction of cells hit, the dose received by the hit, and the biological response of the cell to the dose received eventually determine the effect in tissue. The hit cell may experience detriment, such as change in its DNA leading to a malignant transformation, or it may derive benefit in terms of an adaptive response such as a temporary improvement of DNA repair or temporary prevention of effects from intracellular radicals through enhanced radical detoxification. These responses are protective also to toxic substances that are generated during normal metabolism. Within a multicellular system, the probability of detriment must be weighed against the probability of benefit through adaptive responses with protection against various toxic agents including those produced by normal metabolism. Because irradiation can principally induce both, detriment and adaptive responses, one type of affected cells may not be simply summed up at the expense of cells with other types of effects, in assessing risk to tissue. An inventory of various types of effects in the blood forming system of mammals, even with large ranges of uncertainty, uncovers the possibility of benefit to the system from exposure to low doses of low LET radiation. This experimental approach may complement epidemiological data on individuals exposed to low doses of ionizing radiation and may lead to a more rational appraisal of risk.

• 대한건축학회논문집:구조계
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• 제33권12호
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• pp.3-10
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• 2017

Climate change not only has various impacts such as human shoes, economics, the environment, industry, etc. but the damage caused by this is also increasing, it is expected that severe damage will not occur without efforts to respond to climate change ing. Therefore, as the impact of climate change like the extreme weather phenomenon is dailyized and its strength tends to become stronger, as much as the mitigation measures of climate change, as a comparative effort to reduce the negative impact of climate change, adaptation to climate change is necessary. Especially when the damage caused by climate change (intense heat, torrential rain, cold wave and heavy snow etc.) as an institution responsible for the provision of public services such as public institutions, the socio-economic spread to the nation and the people The effect is very large. We confirmed the level of response to climate change for the entire public institution, and selected climate change risk which is relatively important for specific facilities and business establishments of public institutions, climate change adaptation measures We will try to utilize it as basic material of establishment.

• Geomechanics and Engineering
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• 제24권3호
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• pp.281-293
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• 2021

Uncertainties in geomechanical input parameters which mainly related to inappropriate data acquisition and estimation due to lack of sufficient calibration information, have led wellbore instability not yet to be fully understood or addressed. This paper demonstrates a workflow of employing Quantitative Risk Assessment technique, considering these uncertainties in terms of rock properties, pore pressure and in-situ stresses to makes it possible to survey not just the likelihood of accomplishing a desired level of wellbore stability at a specific mud pressure, but also the influence of the uncertainty in each input parameter on the wellbore stability. This probabilistic methodology in conjunction with Monte Carlo numerical modeling techniques was applied to a case study of a well. The response surfaces analysis provides a measure of the effects of uncertainties in each input parameter on the predicted mud pressure from three widely used failure criteria, thereby provides a key measurement for data acquisition in the future wells to reduce the uncertainty. The results pointed out that the mud pressure is tremendously sensitive to UCS and SHmax which emphasize the significance of reliable determinations of these two parameters for safe drilling. On the other hand, the predicted safe mud window from Mogi-Coulomb is the widest while the Hoek-Brown is the narrowest and comparing the anticipated collapse failures from the failure criteria and breakouts observations from caliper data, indicates that Hoek-Brown overestimate the minimum mud weight to avoid breakouts while Mogi-Coulomb criterion give better forecast according to real observations.

• 동아시아경상학회지
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• 제12권1호
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• pp.23-33
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• 2024

Purpose: This paper explores the nuanced approaches undertaken by private companies in formulating and implementing business continuity plans (BCPs) in response to the unprecedented challenges posed by the global COVID-19 pandemic. Research design, data, and methodology: Utilizing a mixed-methods research design, the study delves into the multifaceted strategies employed by private sector entities, ranging from risk assessment and remote work policies to supply chain diversification and employee well-being initiatives. Result: The findings contribute to a deeper understanding of the evolving landscape of business continuity planning during a pandemic, offering valuable insights for academia, industry practitioners, and policymakers. The research findings present a detailed account of how private companies have tailored their business continuity plans in response to the unique challenges posed by the pandemic. Conclusion: This academic exploration sheds light on the dynamic landscape of business continuity planning in private companies responding to the global pandemic. Insights into the effectiveness of remote work policies, supply chain diversification, employee safety measures, and financial strategies contribute to the understanding of best practices and areas requiring further attention. These recommendations aim to inform future business continuity planning efforts, enhance organizational resilience, and mitigate the impact of global health crises on private sector operations.

• 한국IT서비스학회지
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• 제21권4호
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• pp.123-140
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• 2022

In the ever-increasing online secondhand product market, the perceived risk of online used products purchase was identified as a factor influencing consumer purchase intention. The results of this study are as follows. First, the relationship between the perceived risk of online secondhand purchase and purchase intention was presented with somewhat different results for each sub-risk factor. First of all, a significant negative causal relationship between physical risk, time loss risk, psychological risk, social risk and online used product purchase intention was verified. On the other hand, financial risk and functional risk did not show a statistically significant relationship with online used products purchase intention. Second, as a result of research on the moderating effect of purchasing experience, offline purchasing experience of used products and online purchasing experience were verified differently. First of all, the moderating effect of the online purchase experience of used products was significant only in the relationship between psychological and social risks on the intention to purchase used products online. The experience of purchasing used products online is believed to reduce uncertainty about the surrounding response to purchasing used products online and weaken the intention to purchase used products online by reducing tension and concerns about purchasing them. Other risks, such as financial risk, performance risk, physical risk, time loss risk, and online purchase experience of used products, were verified to have no significant effect on online used products purchase intention. In addition, the offline purchase experience of used products did not verify a significant moderating effect on the effect of all perceived risks on online used product purchase intention.

• 수산해양기술연구
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• 제59권4호
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• pp.354-361
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• 2023

In this study, the AHP (analytic hierarchy process) technique was used to analyze the risk of expected risk factors and fishing possibilities during gillnet fishing within the floating offshore wind farms (floating OWF). For this purpose, the risks that may occur during gillnet fishing within the floating offshore wind farms were defined as collisions, entanglements, and snags. In addition, the risk factors that cause these risks were classified into three upper risk factors and ten sub risk factors, and the three alternatives to gillnet fishing available within the floating OWF were classified and a hierarchy was established. Lastly, a survey was conducted targeting fisheries and marine experts and the response results were analyzed. As a result of the analysis, among the top risk factors, the risk was the greatest when laying fishing gear. The risk of the sub factors for each upper risk was found to be the highest at the berthing (mooring), the final hauling of fishing net, and the laying of the bottom layer net. Based on the alternatives, the average of the integrated risk rankings showed that allowing full navigation/fisheries had the highest risk. As a result of the final ranking analysis of the integrated risk, the overall ranking of allowing navigation/fisheries in areas where bottom layer nets were laid was ranked the first when moving vessels within the floating OWF was analyzed as the lowest integrated risk ranking of the 30th at the ban on navigation/fisheries. Through this, navigation was analyzed to be possible while it was analyzed that the possibility of gillnet fishing within the floating OWF was not high.

• 한국지진공학회논문집
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• 제5권5호
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• pp.47-56
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• 2001

원전 격납건물은 내진 안정성을 확보하기 위해 설계단계에서 여유나 보수성을 부여하게 된다. 원전 구조물의 내진성능 평가는 이러한 여유나 보수성을 배제한 실질적인 성능 및 응답을 기준으로 평가하게 된다. 본 연구에서는 내진성능 평가에 고려되는 구조물의 성능 및 응답관련 계수들 중 그 기여도가 비교적 큰 비탄성 에너지 흡수계수의 산정방법에 대한 비교를 수행하였다. 또한 각종 방법에 따라 산정된 비탄성 에너지 흡수계수에 따른 HCLPF(high confidence of low probability of failure)값의 변화를 분석하였다. 연구결과 원전 격납건물의 비탄성 에너지 흡수계수는 1.5~1.75로 나타났다. 구조물의 내진성능을 명확히 평가하기 위해서는 먼저 구조물의 비선형 거동 및 연성도를 정확히 평가하여야 함을 알 수 있다.

• Environmental Analysis Health and Toxicology
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• 제10권1_2호
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• pp.37-46
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• 1995

The purpose of this research is to estimate a safe environmental level of human exposure to thresholding-acting toxicants in drinking water and recommend the acceptable levels and management plans for maintaining good quality of drinking water' and protecting health hazard. This research has been funded as a national project for three years from 1992 to 1995. This study(the second year, 1993-1994) was conducted to monitor 39 species of noncarcinogenic chemicals such as volatile organic compounds(VOCs), polynuclear aromatic hydrocarbens(PAHs), pesticides and heavy metals of drinking water at some area in six cities of Korea, and evaluate health risk due to these chemicals through four main steps (hazard identification, exposure assessment, dose-response assessment and risk characterization) of risk assessment in drinking water. In hazard identification, 39 species of non-carcinogenic chemicals were identified by the US EPA classification system. In the step of exposure assessment, sampling of tap water from the public water supply system had been conducted from 1993 to 1994, and 39 chemicals were analyzed. Inclose-response assessment for non-carcinogens, reference doses(RfD) and lifetime health advisories(HAs) of lifetime acceptable levels were calculated. In risk characterization of detected chemicals, the hazard quotients of noncarcinogens were less than one except those of manganese and iron in D city.

• 한국지진공학회논문집
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• 제25권2호
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• pp.53-58
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• 2021

Nuclear power plant's safety against seismic events is evaluated as risk values by probabilistic seismic safety assessment. The risk values vary by the seismic failure correlation between the structures, systems, and components (SSCs). However, most probabilistic seismic safety assessments idealized the seismic failure correlation between the SSCs as entirely dependent or independent. Such a consideration results in an inaccurate assessment result not reflecting real physical phenomenon. A nuclear power plant's seismic risk should be calculated with the appropriate seismic failure correlation coefficient between the SSCs for a reasonable outcome. An accident scenario that has an enormous impact on a nuclear power plant's seismic risk was selected. Moreover, the probabilistic seismic response analyses of a nuclear power plant were performed to derive appropriate seismic failure correlations between SSCs. Based on the analysis results, the seismic failure correlation coefficient between SSCs was derived, and the seismic fragility curve and core damage frequency of the loss of essential power event were calculated. Results were compared with the seismic fragility and core damage frequency of assuming the seismic failure correlations between SSCs were independent and entirely dependent.

• 산업융합연구
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• 제17권1호
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• pp.33-39
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• 2019

본 연구에서는 기후변화에 대응하는 도시개발의 실천적 실행을 위해서 기후위험요인 측면과 환경적인 측면으로 대별하여 도시개발 방향과 시사점을 제시하는데 목적을 두었다. 연구방법으로는 정성적인 자료조사와 분석을 통해 이루어졌다. 연구결과, 기후위험요인에 따른 도시개발방향은 도시계획수립시 기후변화 영향을 통합적으로 고려할 수 있는 지역별 부문별 영향 및 취약성 분석을 실시함으로써 자연재난에 대한 피해예방 시스템 구축과 자연재해 위험도 분석을 실시해 도시개발을 할 수 있는 여건 마련의 중요성을 강조하였다. 환경적측면의 도시개발방향은 친환경적인 도시개발을 위해서는 도시계획수립시 대중교통지향적인 도시개발(TOD, Transit­oriented Development)의 추진이 지속가능하고 실행적인 도시개발을 실현하는데 그 필요성을 제시하였다. 향후 연구방향은 보다 더 정량적이고 실증적인 규명을 위한 연구가 보완되어야 할 것이다.