• Nuclear Engineering and Technology
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• 제49권2호
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• pp.411-425
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• 2017

Using a probabilistic safety assessment, a risk evaluation framework for an aircraft crash into an interim spent fuel storage facility is presented. Damage evaluation of a detailed generic cask model in a simplified building structure under an aircraft impact is discussed through a numerical structural analysis and an analytical fragility assessment. Sequences of the impact scenario are shown in a developed event tree, with uncertainties considered in the impact analysis and failure probabilities calculated. To evaluate the influence of parameters relevant to design safety, risks are estimated for three specification levels of cask and storage facility structures. The proposed assessment procedure includes the determination of the loading parameters, reference impact scenario, structural response analyses of facility walls, cask containment, and fuel assemblies, and a radiological consequence analysis with dose-risk estimation. The risk results for the proposed scenario in this study are expected to be small relative to those of design basis accidents for best-estimated conservative values. The importance of this framework is seen in its flexibility to evaluate the capability of the facility to withstand an aircraft impact and in its ability to anticipate potential realistic risks; the framework also provides insight into epistemic uncertainty in the available data and into the sensitivity of the design parameters for future research.

• 한국지구과학회지
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• 제37권5호
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• pp.309-322
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• 2016

This paper presents an analytical framework of Conceptual Understandings of Earth Systems (CUES) that shows a relationship between disciplinary knowledge of Earth systems and the specific thinking skills required to understand that knowledge. This framework is developed through an extensive literature review of students' and teachers' understandings of earth systems concepts and systems thinking in earth science context. This study first presents the categories of disciplinary knowledge of Earth systems, Earth System Knowledge (ESK). This study then illustrates a relationship between categories of ESK and the ontological categories (Matter, Process, Systems) that has been used to study students' conceptual understandings of Earth systems. Finally, this study presents the CUES framework to show the relationship between disciplinary knowledge and thinking skills. The implications of using this framework for curriculum development, assessment, and teacher education and ESS research are discussed.

• 한국과학교육학회지
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• 제32권2호
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• pp.210-235
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• 2012

본 연구에서는 중학생들의 과학 창의적 문제 해결능력을 측정하기 위해 타당도와 신뢰도가 높은 검사도구를 개발하였다. 먼저 과학 창의적 문제 해결 능력에 대한 조작적 정의를 바탕으로 3차원 평가 틀(과학내용, 과학 탐구 기능, 사고력)을 개발하였으며, 이 평가 틀에 맞추어 평가 문항을 개발하였다. 현장 과학 교사들의 검토를 거쳐 예비 검사에 투입할 3과제로 구성된 4개 문항을 확정하였고, 예비 검사 결과를 바탕으로 각 문항의 구체적인 채점 기준과 배점을 결정하였다. 완성된 최종 검사 도구는 내용 및 평가 기준에 대한 과학 교육 전문가와 현장 교사들의 타당도 검증을 거친 후 중학교 1, 2, 3학년 320명에게 투입되었으며, 채점 결과를 바탕으로 채점자간 신뢰도를 검증받았다. 채점 결과 문항 난이도와 변별도 역시 적절한 것으로 나타났다. 앞으로 본 연구에서 개발한 평가 틀과 평가 기준을 활용하여 다양한 학교 급에 적용할 수 있는 다양한 수준의 과학 창의적 문제 해결 능력 평가도구의 개발이 지속적으로 이루어져야 할 것이다.

• Nuclear Engineering and Technology
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• 제46권1호
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• pp.11-26
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• 2014

The analyses carried out within the Seismic Probabilistic Risk Assessments (SPRAs) of Nuclear Power Plants (NPPs) are affected by significant aleatory and epistemic uncertainties. These uncertainties have to be represented and quantified coherently with the data, information and knowledge available, to provide reasonable assurance that related decisions can be taken robustly and with confidence. The amount of data, information and knowledge available for seismic risk assessment is typically limited, so that the analysis must strongly rely on expert judgments. In this paper, a Dempster-Shafer Theory (DST) framework for handling uncertainties in NPP SPRAs is proposed and applied to an example case study. The main contributions of this paper are two: (i) applying the complete DST framework to SPRA models, showing how to build the Dempster-Shafer structures of the uncertainty parameters based on industry generic data, and (ii) embedding Bayesian updating based on plant specific data into the framework. The results of the application to a case study show that the approach is feasible and effective in (i) describing and jointly propagating aleatory and epistemic uncertainties in SPRA models and (ii) providing 'conservative' bounds on the safety quantities of interest (i.e. Core Damage Frequency, CDF) that reflect the (limited) state of knowledge of the experts about the system of interest.

• International Journal of Computer Science & Network Security
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• 제21권1호
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• pp.12-18
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• 2021

This paper proposes a framework for the development of the health recommender system, designed to cater COVID-19 symptoms' self-assessment and monitoring as well as to provide recommendations for self-care and medical treatments. The aim is to provide an online platform for Patient Under Investigation (PUI) and close contacts with positive COVID-19 cases in Malaysia who are under home quarantine to perform daily self-assessment in order to monitor their own symptoms' development. To achieve this, three main phases of research methods have been conducted where interviews have been done to thirty former COVID-19 patients in order to investigate the symptoms and practices conducted by the Malaysia Ministry of Health (MOH) in assessing and monitoring COVID-19 patients who were under home quarantine. From the interviews, an algorithm using user-based collaborative filtering technique with Pearson correlation coefficient similarity measure is designed to cater the self-assessment and symptoms monitoring as well as providing recommendations for self-care treatments as well as medical interventions if the symptoms worsen during the 14-days quarantine. The proposed framework will involve the development of the health recommender system for COVID-19 self-assessment and treatments using the progressive web application method with cloud database and PHP codes.

• 환경영향평가
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• 제9권3호
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• pp.185-202
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• 2000

Uncertainty and variability in Life Cycle Assessment(LCA) have been significant key issues in LCA methodology with techniques in other research area such as social and political science. Variability is understood as stemming from inherent variations in the real world, while uncertainty comes from inaccurate measurements, lack of data, model assumptions, etc. Related articles in this issues were reviewed for classification, distinguish and elaboration of probabilistic/stochastic health risk analysis application in LCA. Concept of focal zone, streamlining technique, scenario modelling and Monte Carlo/Latin Hypercube risk analysis were applied to the uncertainty/variability analysis of health risk in LCA. These results show that this general framework of multi-disciplinary methodology between probabilistic health risk assessment and LCA was of benefit to decision making process by suppling information about input/output data sensitivity, health effect priority and health risk distribution. There should be further research needs for case study using this methodology.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2004년도 추계학술발표회 발표논문집
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• pp.1459-1460
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• 2004

An AHP-based framework for comprehensive comparison of several power technologies haas been developed. A questionnaire has been designed and is about to surveyed for extracting boty weight vectors and subjective evaluation values. The attitude of evaluator groups will be incorporated into these two types of quantification.

• 농약과학회지
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• 제9권3호
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• pp.214-220
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• 2005

초기위해성평가는 신물질 개발시 급성자료와 물리화학적 특성자료를 이용하여 위해성평가를 수행하고 정책결정자들에게 위해성에 관한 정보를 제공하여 의사결정 수단으로 활용되고 있다. 본 연구에서는 초기위해성평가 체계의 틀을 구축하고 구축된 위해성평가 체계를 검증하기 위하여 captan, glyphosate, paraquat dichloride의 세 가지 농약을 대상물질로 하여 인체 및 생태의 초기위해성을 평가하였다. 이때 두 종류의 수계 예측 모형인 GENEEC (GENeric Estimated Environmental Concentration)과 FOCUS (FOrum for the Co-ordination of pesticide models and their USe)가 농약의 노출평가를 위하여 사용되었으며 glyphosate와 paraquat dichloride는 인체 및 생태에 위해성이 낮은 것으로 나타났으나 captan의 어류 위해성은 급성독성이 높은 것으로 나타났다. 이 결과는 U.S. EPA RED (Reregistration Eligibility Decision) 결과와 유사한 경향성을 보여 본 연구체계의 신뢰성을 검증할 수 있었다.

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1213-1220
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• 2022

The Emergency Diesel Generator (EDG) is a critical and essential part of the Nuclear Power Plant (NPP). Due to past catastrophic disasters, critical systems of NPP like EDG are designed to meet high dependability requirements. Therefore, we propose a framework for the dynamic reliability assessment using the Fault Tree and the Dynamic Bayesian Network. In this framework, the information of the component's failure probability is updated based on observed data. The framework is powerful to perform qualitative as well as quantitative analysis of the system. The validity of the framework is done by applying it on several NPP systems.

• Journal of Computing Science and Engineering
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• 제5권1호
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• pp.33-50
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• 2011

In this paper we applied our previously developed assessment framework to the data collected from an internet security readiness survey targeted at households. We used the assessment framework to compute an Internet Security Readiness index for each household, which was in turn derived from Internet Security Readiness capital, skill, and actual uptake/use of infrastructure indices. We then examined the relationships among overall Internet Security Readiness, and the capital, skill, and actual uptake/use of infrastructure related to Internet Security Readiness. In addition, we explored the influence of Internet usage level and experience on Internet Security Readiness.