• 한국수자원학회논문집
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• 제39권8호
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• pp.659-668
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• 2006

수공구조물의 위험도에 관한 불확실성을 검토하기 위하여 본 연구에서는 빈도해석을 통하여 추정되는 설계홍수량의 분산량을 고려한 불확실성 해석을 실시하였다. Gumbel 분포형을 기본 분포형으로 가정하였으며, 모멘트법, 최우도법, 확률가중모멘트법을 이용하여 각 매개변수 추정방법별로 추정된 설계홍수량에 대한 이론적인 분산량을 산정하였다. 이론적으로 유도한 분산량의 특성을 규명하기 위하며 다양한 표본크기와 설계연한, 비초과확률 및 변동계수조건에 대하여 Monte-Carlo 모의를 실시하고 각 매개변수 추정방법별 비교를 실시하였다. 그 결과 확률 가중 모멘트법을 사용한 경우 위험도에 대하여 상대적으로 가장 작은 상대편의 및 상대제곱근오차를 발생시키는 것으로 나타났으며, 최우도법의 경우에는 상대적으로 큰 표본자료에 대해서는 설계연한 및 비초과확률에 관계없이 작은 상대편의 및 상대제곱근오차를 발생시키는 것으로 나타났다. 또한 다양한 변동계수 조건은 상대편의 및 상대제곱근오차의 측면에서 고려하여 볼 때 거의 영향을 주지 않는 것으로 나타났다.

• 대한가정학회지
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• 제38권6호
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• pp.149-169
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• 2000

The purpose of this study was to examine the environmental characteristics of adolescents in low-income families, identify the high-risk & protective factors among environmental contexts surrounding adolescents, and investigate the relative importance of high-risk & protective factors to adolescents'psychological and behavioral adjustment separately. The present study was the primary research of developing prevention program for adolescents'deviant behaviors in low-income families. Subjects of this study consisted of 176 adolescents drawn from 8 social-welfare institutions in Chungbuk province. The pilot study was done to examine the applicability of survey instrument. Data were analyzed by the frequency, percentage, Pearson correlation, stepwise regression using SPSS/WIN program. The results were as followings: 1. There was statistically correlated with each other in environmental high-risk and protective factors except an housing environment. The results implies that environmental contexts itself surrounding adolescents in low-income families can be either high-risk factors or protective factors. 2. The adolescents in low-income families perceived that stresses from consumer and school environments were high-risk factors among other environmental contexts. 3. The adolescents in low-income families perceived that resources from friend and school were protective factors among other environmental contexts. 4. The stresses from friend and eating behaviors were significant factors predicting adolescents'relative psychological adjustment. However, the behavioral adjustment was not predicted by environmental contexts. 5. The resources from school, consumer, and eating behaviors were significant factors predicting adolescents'relative psychological adjustment. Also, the resources from school, eating behavior, and family were predictors of behavioral adjustment. This research implies that the findings can be based on the development of prevention program for adolescents deviant behaviors in low-income families.

• 한국대기환경학회지
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• 제19권2호
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• pp.205-216
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• 2003

We have gathered exposure data on ambient air quality level and investigated dose-response slope factors of air pollutants such as fine particle, HAPs (metals, VOCs, PAHs) and dioxins in Seoul. Theoretical mortality incidences were estimated from exposure to these pollutants. From the results, priorities were ranked in the order fine particle, metals, VOCs, dioxins and PAHs by ordinal scale, and the uncertainties relative to those risk estimates were described.

• International Journal of Human Ecology
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• 제2권1호
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• pp.135-152
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• 2001

The purpose of this study was to investigate the association of protective and risk factors with adolescent delinquency. Using nationally representative data from the National Longitudinal Study of Adolescent Health (Add Health) project, the delinquency level and the influence of individual characteristics, dyadic relationships in the family, school and peer variables on adolescent delinquency were examined by gender. Boys and girls differed in delinquency level with boys showing significantly higher delinquency than girls. The relative influence of protective and risk factors in individual, familial, peer, and school contexts differed by gender as well. More diverse variables influenced the delinquency level of girls than that of boys.

• Nuclear Engineering and Technology
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• 제49권5호
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• pp.1090-1094
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• 2017

The determinants of the public's nuclear power acceptance have received considerable attention as decisive factors regarding nuclear power policy. However, the contingency of the relative importance of different determinants has been less explored. Building on the literature of psychological distance between the individual and the object, the present study demonstrates that the relative effects of different types of perceived risks regarding nuclear power generation differ across acceptance targets. Using a sample of Korea, our results show that, regarding national acceptance of nuclear power generation, perceived risk from nuclear power plants exerts a stronger negative effect than that from radioactive waste management; however, the latter exerts a stronger negative effect than the former on local acceptance of a nuclear power plant. This finding provides implications for efficient public communication strategy to raise nuclear power acceptance.

• Safety and Health at Work
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• 제7권3호
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• pp.251-255
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• 2016

Background: Building demolition can lead to emission of dust into the environment. Exposure to silica dust may be considered as an important hazard in these sites. The objectives of this research were to determine the amount of workers' exposure to crystalline silica dust and assess the relative risk of silicosis and the excess lifetime risk of mortality from lung cancer in demolition workers. Methods: Four sites in the Tehran megacity region were selected. Silica dust was collected using the National Institute for Occupational Safety and Health method 7601 and determined spectrophotometrically. The Mannetje et al and Rice et al models were chosen to examine the rate of silicosis-related mortality and the excess lifetime risk of mortality from lung cancer, respectively. Results: The amount of demolition workers' exposure was in the range of $0.085-0.185mg/m^3$. The range of relative risk of silicosis related mortality was increased from 1 in the workers with the lowest exposure level to 22.64/1,000 in the employees with high exposure level. The range of the excess lifetime risk of mortality from lung cancer was in the range of 32-60/1,000 exposed workers. Conclusion: Geometric and arithmetic mean of exposure was higher than threshold limit value for silica dust in all demolition sites. The risk of silicosis mortality for many demolition workers was higher than 1/1,000 (unacceptable level of risk). Estimating the lifetime lung cancer mortality showed a higher risk of mortality from lung cancer in building demolition workers.

• 대한통합의학회지
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• 제12권2호
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• pp.155-166
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• 2024

Purpose : This study aims to identify key factors for predicting dropout risk at the university level and to provide a foundation for policy development aimed at dropout prevention. This study explores the optimal machine learning algorithm by comparing the performance of various algorithms using data on college students' dropout risks. Methods : We collected data on factors influencing dropout risk and propensity were collected from N University. The collected data were applied to several machine learning algorithms, including random forest, decision tree, artificial neural network, logistic regression, support vector machine (SVM), k-nearest neighbor (k-NN) classification, and Naive Bayes. The performance of these models was compared and evaluated, with a focus on predictive validity and the identification of significant dropout factors through the information gain index of machine learning. Results : The binary logistic regression analysis showed that the year of the program, department, grades, and year of entry had a statistically significant effect on the dropout risk. The performance of each machine learning algorithm showed that random forest performed the best. The results showed that the relative importance of the predictor variables was highest for department, age, grade, and residence, in the order of whether or not they matched the school location. Conclusion : Machine learning-based prediction of dropout risk focuses on the early identification of students at risk. The types and causes of dropout crises vary significantly among students. It is important to identify the types and causes of dropout crises so that appropriate actions and support can be taken to remove risk factors and increase protective factors. The relative importance of the factors affecting dropout risk found in this study will help guide educational prescriptions for preventing college student dropout.

• 마케팅과학연구
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• 제18권2호
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• pp.89-111
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• 2008

디지털 기술의 발전으로 일상생활에 접목시킨 스마트 의류 개발에 관한 연구가 활발히 진행되고 있으나, 실질적으로 착용하게 될 소비자의 인식이나 태도에 관한 연구가 이루어지지 않고 있다. 본 연구에서는 스마트의류의 지각된 혁신속성과 위험지각 차원이 제품 태도와 수용의도에 미치는 영향을 알아보고자 대학생을 대상으로 설문지법을 이용하여 조사하였다. 연구의 결과, 스마트의류의 지각된 혁신속성은 상대적 이점, 가시성, 복잡성의 3가지 요인으로, 지각된 위험은 신체/성과적 위험, 사회심리적 위험, 시간손실 위험, 경제적 위험 4가지 요인으로 추출되었다. 혁신특성 중 상대적 이점, 가시성이, 위험지각 중 사회심리적 위험과 경제적 위험이 제품 태도와 구매의도 예측에 주요한 변인으로 나타났다. 한편 사회심리적, 경제적 위험은 상대적이점과 복잡성을 설명하는데, 신체성과적, 사회심리적, 시간손실 위험은 가시성을 설명하는데 유의한 변인으로 나타났다. 제품 태도는 혁신특성과 구매 의도 사이에서는 부분매개 역할을, 위험지각과 구매의도 사이에서는 완전매개역할을 하는 것으로 나타났다. 본 연구는 스마트의류 구입 시 소비자가 인지하는 혁신특성과 지각된 위험의 유형을 파악함으로써 스마트의류 마케터들이 소비자의 긍정적인 태도 형성을 위한 마케팅 전략 수립 시 활용할 수 있는 기초 정보를 제시하였다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 1999년도 춘계학술발표회논문집
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• pp.43-51
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• 1999

The objective of this research is to ensure that the ports and waterways management system can establish and maintain a reasonable level of safety level during high density passenger operations. The research model was developed included computer based model that could be used that can be used to measure and monitor risk and evolved overtime. The research methodology provides model for assessing relative risk and evaluating risk reduction measures. The risk analysis based on expert judgement was refined overtime. They provide a basis for risk reduction and risk management policies and strategies. The evaluation and validation of risk model and development of data, methods, tools required to measure, monitor and evaluate ports and waterway risk was implemented.

• 산업경영시스템학회지
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• 제22권51호
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• pp.151-161
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• 1999

For many decades, Deterministic DCF approach has been widely used to evaluate investment opportunities. Under new manufacturing conditions involving uncertainty and risk, the DCF approach is not appropriate. In DCF, Risk is incorporated in two ways: certainty equivalent method, risk adjusted discount rate. This paper proposes a determination method of the Risk Adjusted Discount Rate for economically decision making advanced manufacturing technologies. Conventional DCF techniques typically use discount rate which do not consider the difference in risk of differential investment options and periods. Due to their relative efficiency, advanced manufacturing technologies have different degree of risk. The risk differential of investments is included using $\beta$ coefficient of capital asset pricing model. The comparison between existing and proposed method investigated. The DCF model using proposed risk adjusted discount rate enable more reasonable evaluation of advanced manufacturing technologies.