• 한국의학물리학회지:의학물리
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• 제34권3호
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• pp.23-32
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• 2023

Purpose: In radiomics analysis, to evaluate features, and predict genetic characteristics and survival time, the pixel values of lesions depicted in computed tomography (CT) and magnetic resonance imaging (MRI) images are used. CT and MRI offer three-dimensional images, thus producing three-dimensional features (Features_3d) as output. However, in reports, the superiority between Features_3d and two-dimensional features (Features_2d) is distinct. In this study, we aimed to investigate whether a difference exists in the prediction accuracy of radiomics analysis of lung cancer using Features_2d and Features_3d. Methods: A total of 38 cases of large cell carcinoma (LCC) and 40 cases of squamous cell carcinoma (SCC) were selected for this study. Two- and three-dimensional lesion segmentations were performed. A total of 774 features were obtained. Using least absolute shrinkage and selection operator regression, seven Features_2d and six Features_3d were obtained. Results: Linear discriminant analysis revealed that the sensitivities of Features_2d and Features_3d to LCC were 86.8% and 89.5%, respectively. The coefficients of determination through multiple regression analysis and the areas under the receiver operating characteristic curve (AUC) were 0.68 and 0.70 and 0.93 and 0.94, respectively. The P-value of the estimated AUC was 0.87. Conclusions: No difference was found in the prediction accuracy for LCC and SCC between Features_2d and Features_3d.

• 한국CDE학회논문집
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• 제16권4호
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• pp.292-299
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• 2011

Han-ok has a long history and cultural traditions. It has green and healthy and culture but high construction costs, thermal insulation performance of residential and vulnerable to fires and have a weakness for maintenance. However, modernized resident housing, Han-ok is required to improve in terms of environmental aspect due to its weakness for insulating and inconvenience for modem era. Also Han-Ok's building is criticized as a huge dependence on subjective building experiences. This is pointed to be the biggest problem, Han-ok has. Traditionally it does not have a scientific and specific manual for construction. In this research, process simulation was adopted to develop Han-Ok's environmental improvements. In terms of LCC (Life Cycle Cost) aspect, however, Han-Ok's environmental characteristics are examined to suggest an appropriate Han-Ok construction method. Also the result of this research would be utilized to base the information database for efficient constructing and its management in new Han-Ok constructing industry.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.828-829
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• 2011

This paper performs a comparison analysis of two types of HVDC system in Jeju power system. A traditional HVDC transmission system had been composed of line commutated converter based on thyristors and the development of semiconductors enables to apply voltage source converter using IGBTs. The detailed parameters of Jeju power system were considered to make a similar condition with real system in real time digital simulator. Two types of HVDC transmission system were modeled and simulated to compare their characteristics in Jeju power system. The simulation results demonstrate that the VSC-HVDC system has more stable performance due to the fast response speed than LCC-HVDC when the transmission capacity was fluctuated.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.551-556
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• 2004

The deterioration of a shunting locomotive was characterized for the lifetime assessment. The locomotive has been used for shunting works in steel making processes, and in this investigation, various types of technical evaluation methods for the locomotive parts were employed to assess the current deterioration status and to provide important clue for lifetime prediction. Unlike other rolling stocks in railway applications, the diesel shunting locomotive is composed of major components such as diesel engine, transmission, gear box, brake system, electronic devices, etc., which cover more than 70 percent of the total price of the locomotive. Therefore, in this paper, each part of major components in the diesel locomotive was analyzed in terms of the degree of deterioration. The life-cycle-cost (LCC) analysis was performed based on the maintenance and repair history as compared with economical cost to provide the cost-effective prediction, i.e., to assess either repair for reuse or putting the locomotive out of service based on cost-effective calculation.

• Corrosion Science and Technology
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• 제20권4호
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• pp.169-174
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• 2021

In this study, performance tests, a field evaluation, and a life cycle cost (LCC) analysis for high performance coating systems were conducted to prepare a plan to reduce the cost of maintenance coating and contribute to the service life extension of steel bridges by applying high performance coatings to steel bridges that will be constructed in the future. From the deterioration models based on the field evaluation for chlorinated rubber and urethane topcoat systems, which have been applied often, the mean service lives were derived as 20.8 and 26.6 years, respectively. For the other coating systems that have not been applied in practice, the coordination factors were differentially applied with evaluation items. The most durable coating system was predicted to be thermal spray coating (TSC) primer/epoxy intermediate coat/fluoride resin topcoat, with a predicted value as long as 42.2 years. The LCC analysis indicates that partial application of high performance coating, such as TSC and fluoride resin, to specific parts vulnerable to corrosion and ultraviolet ray (UV) is more advantageous than the use of general coating systems.

• 전기학회논문지
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• 제67권12호
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• pp.1717-1722
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• 2018

Parts and units of 8200 series electric locomotive are aging, but and source technology is not secured. As a results, maintenance costs are increasing steadily due to using expensive substitute parts. Therefore, various studies have been conducted to reduce maintenance costs. In this paper, the life cycle cost(LCC) of the developed and conventional products were compared and analyzed about main conversion system in 8200 Series electric locomotive. As a result of analysis, the material cost was the highest in the conventional product among the various item costs. On the other hand, it is confirmed that preventive cost was the highest among the costs about the developed product.

• 한국도서관정보학회지
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• 제40권4호
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• pp.401-425
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• 2009

이 연구는 건축공학 분야의 학문체계와 KDC, DDC, LCC의 분류체계 및 한국연구재단의 연구분야분류표의 건축공학 분야의 분류체계에 대해 비교 분석한 후, 이를 토대로 KDC 건축공학 분야의 분류체계를 개선할 수 있는 방안을 제시하고자 시도하였다. 분석결과 KDC 제5판의 건축공학 분야는 학문발전의 추세를 반영하는 분류항목의 추가, 건축구조공학 분야의 등위류 분류용어의 적절한 전개, 세부 주제의 추가 전개, 적절한 분류용어의 선택, 분류기호, 영문표기의 오류, 분류항목의 상관색인 누락 등에 대한 개선이 필요한 것으로 나타났다. 이 연구에서는 이러한 문제들을 해결하기 위한 개선 방안을 제시하였다.

• 한국태양에너지학회 논문집
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• 제23권1호
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• pp.57-67
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• 2003

This study aims to presents Evaluation Method of Green Remodeling that analyze the value of environment through expense, using the method of life cycle cost and life cycle assessment simultaneously. The results of this study are summarized as follows. Evaluation Model developed in this study can convert economical value of environment into cost by integrating. In addition, the model can apply as a useful tool to estimation of economical design alternative as well as quantification of environmental loads and costs. Evaluation Model presented In this study observe energy consumption and the environmental load emission with qualification, it can forecast effect of environmental cost that cost estimation is expected to be added to energy cost rate by being possible. Synthetically, when Estimation Model and computer program that developed in this study is applies to the construction industry; reasonable management of environmental load is convenient at each step of Green Remodeling. In addition, at preliminary design phase, practical use may be possible by reasonable yardstick about various alternatives and improvement of design alternatives likewise by grasping environmental effect.

• 한국도서관정보학회지
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• 제41권4호
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• pp.5-33
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• 2010

이 연구는 교육학 분야의 학문체계와 KDC, NDC, DDC, LCC의 분류체계 및 한국연구재단의 연구분야분류표의 교육학 분야의 분류체계에 대해 비교 분석한 후, 이를 토대로 KDC 교육학 분야의 분류체계를 개선할 수 있는 방안을 제시하고자 시도하였다. 분석결과 KDC 제5판의 교육학 분야는 학문발전의 추세를 반영하는 분류항목의 추가, 교육학 세부 영역의 등위류 분류용어의 적절한 전개, 세부 주제의 추가 전개, 분류기호의 오류 및 분류항목의 상관색인 누락 등에 대한 개선이 필요한 것으로 나타났다. 이 연구에서는 이러한 문제들을 해결하기 위한 개선 방안을 제시하였다.

• 한국해안·해양공학회논문집
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• 제23권6호
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• pp.422-428
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• 2011

잔교식 안벽의 생애주기비용(Life Cycle Cost, LCC)을 이용하여 신뢰도지수의 최적값을 구하였다. 응답면 기법을 이용한 신뢰성해석을 통해 횡잔교와 돌제식 잔교의 파괴확률을 산정하였다. 파괴확률은 잔교의 파괴 시 복구비용을 산출하는데 활용하였으며 초기공사비와 유지관리비를 모두 고려한 LCC를 최소화시킬 수 있는 신뢰도지수를 찾았다. 지진하중과 접안하중에 대한 다양한 조건에서의 최적 신뢰도지수를 구하였고 이를 통해 신뢰성설계에 사용할 수 있는 목표신뢰도지수를 제안하였다.