• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.484-497
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• 2021

This paper proposes an extended time uncertainty analysis approach in Level 2 human reliability analysis (HRA) considering severe accident management (SAM) strategies. The method is a time-based model that classifies two time distribution functions-time required and time available-to calculate human failure probabilities from delayed action when implementing SAM strategies. The time required function can be obtained by the combination of four time factors: 1) time for diagnosis and decision by the technical support center (TSC) for a given strategy, 2) time for strategy implementation mainly by the local emergency response organization (ERO), 3) time to verify the effectiveness of the strategy and 4) time for portable equipment transport and installation. This function can vary depending on the given scenario and includes a summation of lognormal distributions and a choice regarding shifting the distribution. The time available function can be obtained via thermal-hydraulic code simulation (MAAP 5.03). The proposed approach was applied to assess SAM strategies that use portable equipment and safety depressurization system valves in a total loss of component cooling water event that could cause reactor vessel failure. The results from the proposed method are more realistic (i.e., not conservative) than other existing methods in evaluating SAM strategies involving the use of portable equipment.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1297-1306
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• 2019

Probabilistic safety assessments (PSA) have been used for several decades to visualize the risk level of commercial nuclear power plants (NPPs). Since the role of a human reliability analysis (HRA) is to provide human error probabilities for safety critical tasks to support PSA, PSA quality is strongly affected by HRA quality. Therefore, it is important to understand the underlying limitations or problems of HRA techniques. For this reason, this study conducted a survey among 14 subject matter experts who represent the HRA community of domestic Korean NPPs. As a result, five significant HRA issues were identified: (1) providing a technical basis for the K-HRA (Korean HRA) method, and developing dedicated HRA methods applicable to (2) diverse external events to support Level 1 PSA, (3) digital environments, (4) mobile equipment, and (5) severe accident management guideline tasks to support Level 2 PSA. In addition, an HRA method to support multi-unit PSA was emphasized because it plays an important role in the evaluation of site risk, which is one of the hottest current issues. It is believed that creating such a catalog of prioritized issues will be a good indication of research direction to improve HRA and therefore PSA quality.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.611-616
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• 1997

The Level 1 probabilistic safety assessment(PSA) for Wolsong(WS) 2/3/4 nuclear power plant(NPPs) in design stage is performed using the methodologies being equivalent to PWR PSA. Accident sequence evaluation program(ASEP) human reliability analysis(HRA) procedure and technique for human error rate prediction(THERP) are used in HRA of WS 2/3/4 NPPs PSA. The purpose of this paper is to introduce the procedure and methodology of HRA in WS 2/3/4 NPPs PSA. Also, this paper describes the interim results of importance analysis for human actions modeled in WS 2/3/4 PSA and the findings and recommendations of administrative control of secondary control area from the view of human factors.

• Journal of the Korean Society of Safety
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• v.12 no.4
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• pp.143-152
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• 1997

Probabilistic Safety Assessment(PSA) is an engineering analysis of the possible contributors to the risk from a nuclear power plant. It consist of three phases named as Level 1, 2 and 3. Level 1 PSA mainly focused in this paper is the phase of system analysis which includes the development of accident scenarios and the frequency estimation of each scenario. It covers also the system reliability analysis, component data analysis, and human reliability analysis. PSA have become a standard tool in safety evaluation of nuclear power plants. The main benefit of PSA is to provide insights into plant design, performance and environmental impacts, including the identification of dominant risk contributors and the comparison of options for reducing risk.

• Korean Journal of Human Ecology
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• v.2 no.1
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• pp.12-24
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• 1999

This study attempts to explore the effects of personal, household, and environmental factors on household financial management in financial dimensions. Financial management behaviors are constructed with 5 dimensions : income, expenditure, debt, investment and risk management. The specific objectives of this study are : 1) to examine the level of the financial management behavior to the sub-dimensions. 2) to investigate the factors which influence on the level of financial management behavior to the dimensions. The sample consisted of 792 married women living in Seoul. The statistical methods used for analysis included Reliability, Frequencies, Percent, Mean, Standard Deviation, Multiple Regression Analysis. The major results can be summarized as following 1) Among the sub-dimensions, the score of risk management is the most high, 39.00. 2) There are statistically significant differences in the levels and factors which influence on the financial management behavior to the 5 dimensions.(Korean J of Human Ecology 2(l) : 12-24, 1999)

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.97-108
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• 1998

The purpose of this study was to examine the family resources, stress level, and coping strategies of reemployed wives, to direct the better psycho-physical environment, and to enhance the quality of their home environment for reemployed wives. The data were analyzed with the frequency, percentage, factor analysis, mean(S.D), reliability, and regression using SPSS windows program. The major findings were as follows : (1) There were significant relationships between demographic and socioeconomic characteristics of the family resources and stress level. Personal-psycho resources was important variable in the family resources. The household work and value of household work were most influential. (2) Influential variables on stress level were income and working hours, resources of family task sharing. (3) Influential variables on coping strategies were age, reemployed time, and family task sharing. Coping strategies was effected by the reasons of employment.

• International Journal of Human Ecology
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• v.15 no.2
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• pp.43-57
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• 2014

Consumers differ with respect to the level of green attitudes and green purchase behavious and different consumer would have different perceptions on green market environment. This study attempted to explain how consumers perceive green market environment differently across different consumer groups in attitude-behaviour dimension in green consumption. After identifying the four consumer groups based on their attitude toward green purchase and green purchase behaviours, a multinomial logistic analysis and a stepwise discriminant analysis were conducted. This study found that reliability in green market was the most critical factor that contributes to enlarge positive green consumers. Also, the role of reference persons and adequate price of green products were also found to be important to stimulate green buying. By understanding the different role of those factors in each group of consumers, this study provided group-specific implications to expand green consumers.

• Korean Journal of Human Ecology
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• v.15 no.2
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• pp.293-301
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• 2006

The purpose of this study is to develop a textile knowledge checklist and to analyze university students' textile recognition. After analyzing reliability, difficulty, and discrimination of questions, we developed a standardized tool to measure textile knowledge. The tool has 72 checklist questions, which can be divided into 4 parts: basic property, comfort, management, and finishing. The level of university students' textile knowledge was 68.91 %. The level of basic property was 75.56%, comfort 70.83%, management 64.5% and finishing 64.74%. The recognition of management and finishing was lower than that of basic property and comfort. There existed a significant difference in the textile knowledge by their gender, major, and school year. To elaborate, females, clothing and textile major students, and juniors and seniors showed higher level of textile knowledge. It seemed that comfort was more professional item than management in textile knowledge.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.3
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• pp.18-26
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• 2017

Defense industries which require high reliability need an optimized quality management system with well-planned implementation. And the government should examine the overall status of defense industries, then establish practical policies with a proper support plan in required areas to upgrade the quality management level of manufacturers. Thus, DTaQ developed the model for 2 years from 2014, which specialized in quality management level analysis for defense industries. And a survey has been undertaken with that model by DTaQ and Korea Research Center in 2016. The surveyed companies randomly sampled among those which have more than 30 employees and delivery history over past 3 years, and finally 106 defense industries were selected. This paper present survey method and indexes for survey of defense industry quality management level. The survey was conducted in the order of planning, data collection and data processing, and the validity and reliability of the data were verified to increase objectivity of survey results. The survey contents mainly consist of system quality and management quality. System quality includes Product Development Management, Production Operation Management, supply chain quality management, Safety & Environment Management and Reliability Management, on the other hand, management quality includes Strategic Leadership, Human Resource Management, Customer Market Management and Information & Knowledge Management. Thus this proposes the current overall quality management status of the 106 defense industries and shows level differences by company sizes and manufacturing sectors based on the result of survey. Specifically, this paper enables to track the areas which need prompt government support with the policy directions to make quality management level higher. Therefore, it is expected that this can be used as reference data in establishing quality policies for military supplies in the future.

• Korean Journal of Human Ecology
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• v.22 no.6
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• pp.633-647
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• 2013

This study considered whether intergenerational ambivalence has implications for elderly's psychological well-being so as to improve relationship between adults children and their parents and the qualities of the elderly lives. Subjects were 346 elderly parents whose ages 60 over. The statistics used for data analysis were reliability, frequency, percentage, mean, standard deviation, one way ANOVA and multiple regression. The results of this study were as follows; 1)The degrees of elderly's ambivalence of their adult children were 10.07, the data showed lower than median. 2)The elderly's ambivalence level significantly according to spouse, career, religion, relation of the adults children, and ambivalence level were associated with importance of the adults children, education. 3)The variables that affect the elderly's ambivalence level were spouse, importance of the adults children, education, religion, relation of the adults children, career, which explained about 19% of the total variance.