• Journal of Science Education
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• v.45 no.3
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• pp.275-291
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• 2021

The purpose of this study is to analyze the level and characteristics of system thinking of middle and high school students on cycle of matter in the Earth system considering the impact of human activities on the cycle. For this purpose, we developed items for assessment and assessment rubric through the analysis of 2015 revised curriculum and applying systems thinking, respectively. Middle and high school students who participated in the Korea Earth Science Olympiad were the subjects of this study. The level of system thinking was determined using the assessment rubric for student responses collected using items for assessment. The characteristics of system thinking were identified using word analysis. Based on these, the improvement of the curriculum considering the impact of human activities was discussed. The results of the study are as follows: first, the system thinking level of most secondary school students was low in identifying or classifying system elements for matter cycle, and high levels, such as system relationship or generalization of patterns, were found to be relatively small. It was found that students had a higher level of system thinking in the carbon cycle than in the water cycle. Second, in terms of the characteristics of system thinking about water cycle, water was recognized as a major system element and mainly related with evaporation between atmosphere and other system elements. Whereas, in the carbon cycle, carbon dioxide was regarded as a major system element, and photosynthesis and respiration were represented in relation with the biosphere. Third, for education considering the impact of human activities on the matter cycle in the Earth system, it is proposed improving the curriculum considering the socio-ecological system by extending the existing earth system.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.751-756
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• 1998

고리 1호기 원전 수명 연장을 위한 가압열충격(Pressurized Thermal Shock : PTS) 해석은 확률론적 안전성 평가 방법에 따라 수행된다. 본 연구는 가압열충격 상세 해석 연구의 일환으로 가압열충격 해석을 위한 계통해석시 사용되는 최적 평가(Best Estimate) 방법과 기존의 PCT(Peak Cladding Temperature) 관점의 해석에 사용되는 결정론적 안전성 평가 방법간의 해석 방법론 차이에 의한 열수력 거동의 상이점을 평가하기 위함이다. 이를 위해 1998년 설치 예정인 고리 1호기 교체 증기발생기(Replacement Steam Generator ; RSG) 안전성 분석 보고서$^{[1]}$ 의 주증기관 파단사고 해석 결과와 동일한 파단 크기 및 운전 출력에 대해 최적 평가 방법론에 따라 해석된 본 연구의 해석 결과를 비교, 평가하였다. 해석 결과 전출력 소형 주증기관 파단 사고에서는 터빈 유량 모델링 및 반응도 계수, 고온 영출력 대형 파단 사고에서는 가압기 모델, 반응도 계수 및 정지여유도가 해석 방법론에 따른 열수력 거동의 차이에 영향이 큰 것으로 평가되었다

• Science of Emotion and Sensibility
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• v.14 no.2
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• pp.279-292
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• 2011

This research explores the differences of two consumption behaviors from the thinking style they elicit. Specifically, we predict that more utilitarian attributes(vs. hedonic attributes) may be used when evaluating utilitarian products whereas more hedonic attributes(vs. utilitarian attributes) may be used when evaluating hedonic products. In addition, this research considered two different thinking styles: rational thinking style and experiential thinking style, and try to find out whether different product attribute information could elicit different thinking style and whether the thinking style has any effect on product evaluation. The data reported in this research demonstrates the following results. Firstly, people use different criteria when judging different types of product. That is, when judging utilitarian product, they are more likely to use utilitarian attribute as evaluation criteria, on the contrary they inclined to use hedonic attribute as evaluation criteria when choosing hedonic product. Secondly, different types of attribute informations could elicit different thinking style. Utilitarian attribute informations elicit rational thinking style whereas hedonic attribute informations elicit experiential thinking style. Finally, if people engage in rational thinking elicited in processing utilitarian attribute informations, the evaluation of utilitarian product is enhanced. But even though people engage in experiential thinking in processing hedonic attribute informations, the evaluation of hedonic product is not improved.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2006.05a
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• pp.294-299
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• 2006

한국에서는 석유화학 산업의 역사가 30년 이상이 되어 잠재적인 사고의 위험 가능성이 높아지고 있다. 지금까지의 석유화학 산업에서의 전통적인 위험성 평가와 시스템의 제어는 기계적인 결함에만 중점을 두었기 때문에 인간의 행동을 제어하는 것은 간과하여 왔다. 비록 자동화 기술가 제어기술의 발전이 필요함에도 불구하고 인간의 의사 결정 요소는 석유화학 산업에서 사고를 예방하는데 필수적이다. 대부분의 심각한 사고는 부적절한 인간의 행동과 안정장치의 기계적인 결함이 동시에 존재할 경우에 발생한다. A-HRA(Advanced Reliability Analyzer) 소프트 웨어는 석유화학 플랜트 내에서의 인적오류 확률을 분석하고 사고 데이터를 축적하기 위하여 개발되었다. A-HRA 프로그램을 이용하여 1960년대 이후부터 최근 까지 한국의 석유화학 산업에서 발생하여온 인적오류 사고 데이터를 입력하고 사고마다의 근본원인과 수행영향인자를 분석하였다. 이 본문에서는 Root cause Aanlysis을 통한 결과와 PIF(Performance Influencing Factor) 평가 결과를 보여준다. 이 분석 결과는 석유화학 산업의 안전을 극대화 시키면서도 인적오류 제어를 통하여 안전비용을 최저화 시킬 수 있는 대책을 제시할 것이다.

• Journal of the Korean Society for Railway
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• v.12 no.6
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• pp.936-943
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• 2009

In this study, a risk assessment model based on the ETA (Event Tree Analysis) and FTA (Fault Tree Analysis) is developed according to the procedure of hazard analysis and risk assessment in order to estimate the risk quantitatively. The FTA technique is applied to estimate the branch probability (frequency) and the ETA technique is applied to estimate the consequence for each branch path on the ET (Event Tree). A risk assessment model is developed by the combination of those ETA and FTA. In addition, the reliability and the validity of the risk assessment model are verified by comparing the risk estimated through the developed model with the actual equivalent fatality.

• Nuclear industry
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• v.10 no.9 s.91
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• pp.62-65
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• 1990

• Nuclear industry
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• v.13 no.4 s.122
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• pp.41-48
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• 1993

• Fire Science and Engineering
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• v.32 no.3
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• pp.76-87
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• 2018

This study describes the damage effects modeling for a quantitative prediction about the hazardous distances from pressurized chlorine saturated liquid tank, which has two-phase leakage. The heavy gas, chlorine is an accidental substance that is used as a raw material and intermediate in chemical plants. Based on the evaluation method for damage prediction and accident effects assessment models, the operating conditions were set as the standard conditions to reveal the optimal variables on an accident due to the leakage of a liquid chlorine storage vessel. A model of the atmospheric diffusion model, ALOHA (V5.4.4) developed by USEPA and NOAA, which is used for a risk assessment of Off-site Risk Assessment (ORA), was used. The Yeosu National Industrial Complex is designated as a model site, which manufactures and handles large quantities of chemical substances. Weather-related variables and process variables for each scenario need to be modelled to derive the characteristics of leakage accidents. The estimated levels of concern (LOC) were calculated based on the Gaussian diffusion model. As a result of ALOHA modeling, the hazardous distance due to chlorine diffusion increased with increasing air temperature and the wind speed decreased and the atmospheric stability was stabilized.

• Nuclear Engineering and Technology
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• v.16 no.3
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• pp.136-140
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• 1984

A new medal is presented in order to evaluate the risk from a nuclear facility following accidents directly combining the on-site meteorological data using the Monte Carlo Method. To estimate the radiological detriment to the surrounding population-at-large (collective dose equivalent), in this study the probability distribution of each meteorological element based upon on-site data is analyzed to generate atmospheric dispersion conditions. The random sampling is used to select the dispersion conditions at any given time of effluent releases. In this study it is considered that the meteorological conditions such as wind direction, speed and stability are mutually independent and each condition satisfies the Markov condition. As a sample study, the risk of KNU-1 following the large LOCA was calculated, The calculated collective dose equivalent in the 50 mile region population from the large LOCA with 50 percent confidence level is 2.0$\times$10$^2$ man-sievert.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.870-876
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• 1998

원자로용기의 안전성은 가동중 운전조건과 조사취화등으로 인한 재료의 열화(degradation)를 검토함으로써 평가되는데, 특히 운전조건중, 비상사태에 해당하는 가압열충격에 관한 평가가 최근 중요한 안전문제로 부각되고 있다 본 연구의 목적은 가압열충격 사고중 소규모 냉각재 손실사고(Small LOCA)가 발생하는 경우, 원자로용기 내벽에 존재하는 균열의 안전성을 유한요소해석을 통해 평가하는 것이다. 본 연구에서는 Small LOCA 발생시 원자로용기의 내벽에 존재하는 균열의 종류, 방향, 균열형상비 및 클래드부의 두께가 응력확대 계수 계산에 미치는 영향을 평가하였으며, 이를 위해 총 14가지 경우에 대해서 3차원 유한요소해석을 수행하였다. 이러한 Small LOCA 해석수행을 기초로 다양한 가압열충격 사고에 대한 유한요소해석 모델링 기법, 해석 기법, 후처리 기법을 제시하였다.