• Nuclear Engineering and Technology
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• 제42권5호
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• pp.590-599
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• 2010

Recently, efficient operation and practical management of power plants have become important issues in the nuclear industry. In particular, typical aging parameters such as stress and cumulative usage factor should be determined accurately for continued operation of a nuclear power plant beyond design life. However, most of the major components have been designed via conservative codes based on a 2-D concept, which do not take into account exact boundary conditions and asymmetric geometries. The present paper aims to suggest an effective fatigue evaluation methodology that uses a prototype of the integrated model and its transfer functions. The validity of the integrated 3-D Finite Element (FE) model was proven by comparing the analysis results of individual FE models. Also, mechanical and thermal transfer functions, known as Green's functions, were developed for the integrated model with the standard step input. Finally, the stresses estimated from the transfer functions were compared with those obtained from detailed 3-D FE analyses results at critical locations of the major components. The usefulness of the proposed fatigue evaluation methodology can be maximized by combining it with an on-line monitoring system, and this combination, will enhance the continued operations of old nuclear power plants.

• Nuclear Engineering and Technology
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• 제53권2호
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• pp.393-398
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• 2021

Current risk assessment of Spent Nuclear Fuel (SNF) transportation has the problem of the incomplete risk factors consideration and the general particle diffusion model utilization. In this paper, the accident frequency calculation and the detailed simulation of the accident consequences are coupled by the integrated risk assessment method. The "man-machine-environment" three-dimensional comprehensive risk indicator system is established and quantified to characterize the frequency of the transportation accidents. Consideration of vegetation, building and turbulence effect, the standard k-ε model is updated to simulate radioactive consequence of leakage accidents under complex terrain. The developed method is applied to assess the risk of the leakage accident in the scene of the typical domestic SNF Road Transportation (SNFRT). The critical risk factors and their impacts on the dispersion of the radionuclide are obtained.

• 한국환경복원기술학회지
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• 제15권5호
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• pp.49-67
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• 2012

Studies on landscape ecology have focused on conceptual aspects, while empirical focus for spatial planning has been rarely conducted. This study conducted an empirical analysis to enhance landscape ecological performance of urban developments using landscape ecology. To do so, concrete criteria and standards to analyze structural, functional and variational mechanisms of urban landscape ecology were developed. An integrated landscape ecology assessment model that can be applied to urban development planning was established by combining the criteria. Next, Landscape Ecological Management System (LEMS) was developed to implement an integrated assessment using GIS. To verify the effectiveness of the system, a case study was conducted using LEMS on Byulnae City in the Seoul Metropolitan Area. The LEMS can be useful for urban planners and policy makers in their selection of desirable planning alternatives. Moreover, the LEMS developed in this study can be a useful tool for academia in terms of the implementation of further related studies, and for planning professionals in their environmental impact assessment tasks.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.49-56
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• 2001

The techniques to make assessment of the structural integrity of underground structures include Infrared thermagraphy, GPR using the reflection of the electromagnetic wave, ultrasonic test, seismic methods using the propagation of elastic wave, and etc These methods have pros and cons in the assessment of the structural integrity in the complex environment of the underground structure, so that a single method alone is not enough to evaluate parameters required for the assessment. In this study, a new seismic method was proposed to improve the existing methods and to provide an additional information like stiffness of concrete. The proposed method combines the advantages of the modified impact-echo test and the SASW method. To verify the validity of the proposed method, a large scale model of a tunnel concrete liner was built and the proposed method was applied to the center of the model and also to the corner of the model which has several distinct reflection boundaries.

• 한국추진공학회지
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• 제23권4호
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• pp.98-103
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• 2019

함정 운용 장비의 건전성 예측은 유지보수의 효율성 및 긴박한 상황에서의 운용성능 유지를 위한 필수 요소이다. 최근 함정의 양적인 증가와 작전반경 확대에 따라 운용성능 유지를 위해 통합조건평가시스템(ICAS)을 도입하여 운용중이며, 관련기술 국산화를 위해 다각도로 연구가 진행되고 있다. 본 논문에서는 함정 운용 장비인 디젤발전기의 건전성 예측방법 중 데이터기반 모델 적용에 대한 결과를 제시 하였다.

• 환경영향평가
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• 제10권3호
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• pp.235-243
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• 2001

Since the middle of 1990s, in Korea a few researches on the optimal management technologies combining numerical model and GIS for the management of water environment in drinking watershed area and reservoir such as Paldang Lake have been carried out. In this study, the integrated water environment management system was been suggested to efficiently reflect the public awareness of the environment by integrating the web based distributed data collection system, GIS, public hearing system and water quality model. As all the components of the system have been developed using the World Wide Web and all data have been collected from the relevant agencies through the Internet, the water quality model could be implemented on the web directly. In consequence, the environmental geographic information in Paldang Lake could be acquired and analyzed through the Internet. The system can rapidly respond to the public right to know on environment, so the public will willingly participate in the governmental projects on environment. To verify the usability of the developed system, it has been applied to Paldang Lake. Especially when the web based model has been used, users can easily and confidentially get the prediction results by applying the minimum number of parameters for the water quality model. This model will provide clearness and scientific bases in the process of water quality prediction for the sensitive sites where there are critical conflicts between the residents and the developers. In this study, rapid water environment management technique without spatial and time limit has been suggested, which can contribute to the efforts on the government and the public participation.

• 한국IT서비스학회지
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• 제12권4호
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• pp.255-265
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• 2013

This paper proposes a DEA-AR model for the efficiency evaluation of the iron ore brands in an integrated steel mill. The input factor is defined as unit cost of each brand based on CIF and two output factors are chosen as Fe and Al which are the important ingredients of iron ore. The relative importance between two output factors is determined by several experts using AHP model. The efficiency of each brand is determined using DEA and DEA-AR models. The negative correlation between the DEA-AR efficiency and the unit cost (CIF) is shown as significant whereas no significant correlation exist between the efficiency and the output factors. Also, the Kruskal Wallis rank sum test shows that there exist efficiency differences among the iron ore types whereas no difference is shown among the countries. The result could be utilized in selecting good brands of iron ores based on the DEA-AR efficiency in an integrated steel mill.

• 한국국방경영분석학회지
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• 제37권1호
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• pp.87-97
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• 2011

본 논문에서는 앞으로 개발되어 전력화 예정인 제병협동통합연동체계에서 모델간 연동으로 인해서 발생가능한 문제점 중의 하나인 전투 피해평가 차이를 극복할 수 있는 근접전투 피해평가 전문가시스템을 제안하였다. 제병협동통합연동체계에서 서로 다른 모델에 속한 부대간 교전이 발생할 때에 피해평가 결과가 많은 차이를 보이고 있었는데, 이러한 피해평가의 차이는 제병협동통합연동체계의 신뢰성 문제와 직관되는 중요한 부분으로 반드시 해결되어야 할 부분이다. 이러한 문제점을 해결하고 신뢰할 만한 근접전투 피해평가를 위해 전문가시스템을 의사결정나무를 이용해서 제안하였다. 제안하는 전문가시스템은 실험 결과를 통해서 신뢰할 만한 결과를 보였고, 별도의 시스템으로 운용하지 않고 기존 모델에 모듈형식으로 탑재되기 때문에 시스템 측면에서 제병협동통합연동체계를 보다 단순화 시킬 수 있고 예산 절감의 효과를 기대할 수 있다.

• 한국정보기술학회논문지
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• 제16권12호
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• pp.115-125
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• 2018

2015 개정 교육과정의 핵심은 성취평가제의 적용과 확산으로서 학생들의 학업 성취 평가에서 있어서 경쟁적인 상대평가에서 벗어나 학생들이 각각의 평가기준에 따라 어느 정도의 학업 성취를 달성하였는가를 평가하는 것이다. 이를 위해서는 교수학습 설계와 수행 및 평가 프로세스를 통합 관리할 수 있는 평가기준 및 성취수준 지원 시스템이 필요하다. 본 논문에서는 교육과정의 성취기준 자료, 수업설계 자료, 학습내용 자료, 평가설계 자료, 평가결과분석 자료 및 피드백 자료들을 연계할 수 있는 통합 데이터모델을 설계하고 이에 기반한 성취평가 지원 시스템을 설계한다. 설계한 통합 데이터 모델을 기반으로 학습자 대쉬보드 웹페이지 프로토타입을 구현하고 학생평가지원포털과의 검색 기능을 비교함으로써 제안한 모델의 퀄리티를 평가하였다.

• 환경영향평가
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• 제10권2호
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• pp.99-108
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• 2001

This study was performed to develop an information processing system for the sound conservation of soil and groundwater resources. The system contains numerical models and geographic information systems for underground flow and contamination. Multidimensional Finite Element Model for Subsurface Environment (MFEMSE) was invented to analyze underground flow and pollution problems of water and gas phases. Newly developed and conventional models (MODFLOW, MOC3D, MT3D, PMPATH, PEST, UCODE) were integrated with GIS (ArcView) for the construction of an integrated information management system of subsurface environment. This system was applied to the management of three mineral water companies located in clean high mountain basin. Desirable management criteria and operational strategies were suggested using this system. The system was constructed to be applied for the broad sense of decision supporting tools in related topics of this study, so that it can be used not only for the prevention regulations, but also for clean up projects.