• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.1
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• pp.34-46
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• 1999

전 세계적으로 항공기의 노후화에 따른 안전성 확보와 수명연장을 위한 대책 연구가 활발하다. 미국의 경우 군용기 (주로 수송기)의 평균수명은 40년을 넘어서고 있으며 이들은 아직도 $20{\sim}30년$ 더 사용될 예정이다. 민간항공기의 경우에도 군용기만큼은 아니지만 노후화하고 있기는 마찬가지이다. 수명연장을 위해 여러가지 비파괴검사 기술이 활용되고 있으며, 새로운 비파괴 시험 평가 검사 방법들이 속속 개발되고 있다. 항공기의 안전을 위협하는 기체구조 손상의 2대 주범으로는 부식과 피로를 꼽을 수 있으며, 이를 탐지하고 평가하기 위한 경제적인 검사방법에 대한 연구가 미국을 중심으로 활발하게 진행되고 있는데, 이에 대한 최근 현황을 살펴본다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.170-171
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• 2016

The unity of korean peninsula have traditionally been established as major policy in korea government. Present government also set Trust Process on the Korean Peninsula as national high-level strategies for unity, and construction field related directly to living of north korean as major industry which would be implemented in early stage. Deterioration level of architectural facilities in north korea is known as very high, so a huge budget would be required to improve aging architectural facilities for stability of social and living of north korean. Therefore the purpose of this study deduct financing plan for improving aging architectural facilities in north korea and selection of optimal alternative securing effectiveness. The results of this study could be utilized as preliminary data for establishment of master plan and policy for improving deteriorated facilities in situation of united korean peninsula.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.133-138
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• 2002

온풍난방기 20대를 대상으로 온풍난방기의 베기가스중 탄산가스농도, 온풍온도차, 배기가스온도 및 열효율을 조사하여 사용연수별로 분석하였으며 주요 결과는 다음과 같다. 가. 사용연수별 온풍난방기 배기가스중 탄산가스농도와 온풍온도차는 사용연수에 따른 조사표본의 부족으로 큰 차이가 있었다고 하기는 어렵고 정확한 조사를 위해서는 보다 많은 대수가 필요할 것으로 판단된다. 나. 사용연수별 배기가스온도는 사용연한이 오래될수록 높아졌다고 판단된다. 이는 열교환기에서 흡입공기와 연소열이 열교환이 충분히 이루어지지 않았거나, 버너노즐의 노후화, 버너송풍기, 온풍난방기 송풍기의 노후화에 따른 결과라 여겨진다. 사용연수에 따른 배기가스온도는 회귀방정식 Y= 79.032Ln(X) + 116.66 ($R^2$= 0.6784)로 나타낼 수 있었다. 다. 사용연수별 온풍난방기의 열효율은 사용연한이 오래될수록 감소하는 경향을 보였으며 회귀방정식 Y = 95.167 X $^{-0.054}$ ($R^2$= 0.5696)로 나타낼 수 있었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.609-615
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• 2006

Crack and seat method has been used in United States to prevent reflection cracks of overlay that may be caused by excessive movement at discontinuity of old concrete pavement. This method provide optium space of discontinuity by generating additional discontinuity in old concrete pavement. In this study the effect of various factors on the performance such as IRI and distress at after applying crack and seat method were investigated by using LTPP data.

• Nuclear industry
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• v.8 no.12 s.70
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• pp.64-69
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• 1988

원자로수화학은 현재의 문제해결기술에서 앞으로는 문제예측형으로 전환되어야 한다. 현재 가동중에 있는 플랜트가 점점 노후화되어 가고 있는 현상황에서는 노후에 따른 트러블 예측의 중요성이 점차 증대될 것이다.

• Proceedings of the Korean Society of Rural Planning Conference
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• 1998.03a
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• pp.41-44
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• 1998

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2004.11a
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• pp.26-26
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• 2004

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.29 no.8
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• pp.34-38
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• 2000

설비시스템의 노후화로 인하여 시스템의 갱신시, 다양한 신설 설비 대체안의 LCC 평가를 건축설비 종사자들이 간단하게 수행하기 위한 LCC 평가 프로그램(POWER LCC)의 개발 사례를 소개한다.

• Korean Journal of Construction Engineering and Management
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• v.18 no.2
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• pp.3-11
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• 2017

Aging buildings over 15 years reaches about 74% of 177 thousand buildings in Domestic public buildings. Due to the aging building, the energy loss is a serious problem. In order to reduce the energy usage through improving the energy efficiency on the existing buildings, the government & the local autonomous entity conduct the energy efficiency projects through the remodeling, repairing & equipment replacement on the existing buildings. The green remodeling is applied to the existing public buildings in recently revised the act on the creation and support of green building. However, the standard is not obvious that the work scope of green remodeling, financing and project delivery method. This paper propose is to suggest project delivery system for vitalizing the green remodeling. Green remodeling is defined on basis of the occurring work under project life cycle based on the existing building process and the financing method for owners and companies and the project delivery system according to work scope of green remodeling are proposed in this paper

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.207-221
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• 2011

More than sixty percentage of highway in South Korea were constructed by concrete pavements and more than half of the concrete pavements were twenty years or older. The most of highway have difficulty in providing detour due to the traffic and road condition of South Korea. So far, asphalt concrete has been used for the overlay of aged cement concrete pavement. However, the frequent early damage and maintenance of typical asphalt overlay due to repetitive maintenance causes inconvenience of road users and expensive costs. It is necessary to investigate the factors affecting the performance of asphalt concrete overlay to improve the performance of asphalt overlay. However, the performance data of asphalt concrete overlay in South Korea does not exist. In this research, to investigate on the factors affecting the life of asphalt concrete overlay was attempted based on statistical analysis of the performance data of asphalt concrete overlay included in LTPP (Long-Term Pavement Performance) Database of U.S.A.