• Nuclear Engineering and Technology
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• v.42 no.5
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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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• v.53 no.2
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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.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.5
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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.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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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.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.4
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• pp.98-103
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• 2019

Integrity prediction of the operation equipment of naval vessels is essential to maintain the efficiency of the operation performance in urgent situations. Recently, the integrated condition assessment system(ICAS) was introduced and maintained to improve operational performance. This technology is related with ICAS, and it must be localized through extensive research. In this paper, we present the results of applying the data-driven model to the predictability methods of diesel generators, which are naval vessel operation equipment.

• Journal of Environmental Impact Assessment
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• v.10 no.3
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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.

• Journal of Information Technology Services
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• v.12 no.4
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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.

• Journal of the military operations research society of Korea
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• v.37 no.1
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• pp.87-97
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• 2011

In this paper, we propose a new close combat expert system to overcome the difference of combat damage assessments between combat units belong to their own model in Combined Arms Integrated Interoperability System(CAIIS) which will be deployed in the early future. When it happens to engage in a battle among combat units belong to their own model in CAIIS, the result of damage assessment is different severely. This is related to CAIIS's confidence and need to be overcome. We propose the expert system for close combat damage assessment with a decision tree. Simulation results show that the proposed expert system is valid well. Because the proposed expert system is made not as an independent system but as an inner module type of CAIIS, CAIIS will be simpler system than we expect. And we will hope to reduce the cost of CAIIS.

• The Journal of Korean Institute of Information Technology
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• v.16 no.12
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• pp.115-125
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• 2018

The one of goals of the 2015 revised national curriculum is the successful application of achievement standards-based assessment, which assesses both the results and process of learning, ensuring that all students have achieved the educational objectives, to schools. Therefore, an achievement standards and evaluation support system is required to manage a whole process of teaching and learning based on achievement standards and provide the personalized assessment feedback to students to improve their achievement levels. In this paper, we perform a design of integrated data model and system of teaching plan, subject content, assessment plan, assessment result, and feedback data is required based on an achievement standards repository. In addition, we create a student's dashboard webpage, which representing different types of achievement of the student, and perform the comparative analysis of data models to evaluate the quality of the proposed model.

• Journal of Environmental Impact Assessment
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• v.10 no.2
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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.