• Journal of Korean Society of Steel Construction
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• v.18 no.6
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• pp.747-758
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• 2006

With the growth of economy, the esthetic values of bridges become significant points in the decision process of a type of new bridges. So, it is common that a long-span bridge or a multi-purpose bridge are selected as the type of new bridges. Also, the economic growth derives increase in traffic and then the increased traffic derives multi purpose bridges from the decision process of bridge types. In the multi-purpose bridges with private fund, the construction cost is simply alloted to several organizations according to the percentage of participation and usage. But the allotment of the maintenance cost is not simple. Because the loads and safety factors in design are different between the criterion of design of highway bridges and that of railway bridges. In this study, we verify the possible problems in case of allotment method of maintenance cost in foreign examples as well as domestic example. As one of the method of determination of allotment ratio in maintenance cost, the method based on the stress of structural analysis is presented and it can be an example in the similar problem later.

• 농업기술회보
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• v.46 no.1
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• pp.36-37
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• 2009

크리스마스를 상징하는 화려한 포인세티아는 겨울철의 대표적인 분화이다. 포인세티아 수요는 매년 괄목할 만한 성장을 하여 겨울 꽃시장의 주요 상품으로서 자리 매김을 하고 있지만 그동안 외국 품종에 대한 높은 로열티 지불로 화훼농가 경영에 큰 부담이 되었다. 농촌진흥청에서는 포인세티아 신품종을 육성, 보급하여 로열티 경감과 화훼농가의 안정적인 소득 증대를 위해 노력하고 있다. 포인세티아는 단일성 식물로 보통 자연일장이 줄어드는 10월부터 이듬해 3월 중순까지 꽃눈을 형성한다. 이 시기는 일장단축과 함께 온도도 영향을 미치며 일장조절에 의한 연중출하가 가능하다. 겨울철 출하를 목표로 재배중인 포인세티아는 적정 온도유지, 환기에 의한 습도관리, 병해충 방제 등 환경관리에 특별히 유의해야 한다.

• Water for future
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• v.47 no.4
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• pp.40-44
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• 2014

• Water for future
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• v.48 no.4
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• pp.60-64
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• 2015

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.151-158
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• 2003

현재 각 도시철도 운영기관이 사용하고 있는 부품코드체계는 구 정부물품 분류체계 11자리를 수요한 코드체계로의 군, 급의 2단계 분류로 구성되어 있어, 분류단계의 제약이 존재할 뿐만 아니라 분류체계의 구조적 문제로 군, 급, 품명의 빈번한 통합, 삭제에 따른 코드 관리의 어려움이 존재하고 있다. 또한, 사용자가 원하는 물품을 해당 분류체계로 찾아가기 위한 그룹별 탐색과 통계적 분석이 불가능한 실정이다. 이러한 분류체계의 문제점과 향후 차종의 노후화로 발생될 관리품목의 증가로 업무능률 저하가 예상되기 때문에 새로운 체계의 표준화된 부품코드체계가 절실히 필요한 실정이다. 본 논문은 산업 발전에 따르는 확장성과 세분화에 대한 분류구조의 탄력성을 가지고 객관적으로 분류 추가 및 변경이 가능하도록 하고, 정부 및 국제기관 표준권고안과 호환성을 가질 수 있는 표준 부품코드체계를 제정하기 위한 연구결과이다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.3
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• pp.118-122
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• 2010

The study presents a standard time-temperature curve to evaluate the fire performance of subway tunnel structures. The central subway section is 135km long in Korea, the fourth longest in the world. The number of subway tunnels has been increasing rapidly and fire risk is proportional to the tunnel length. However, an adequate time-temperature curve for subway tunnel fires does not exist. Therefore, we studied a proposed foreign fire design model for which the heat rate is based on the traffic, and we present an appropriate time-temperature curve for Korean subway tunnels. The ISO 834 curve was used as a fire design model and the temperature distribution in the tunnel was estimated using numerical analysis. This led to a proposal for effective measures against subway tunnel fires.

• Land and Housing Review
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• v.3 no.1
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• pp.97-109
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• 2012

For the design of underpass structures, -1.0m(G.L) ground water level guideline for the design of railway, subway, utility tunnel etc, is still being used in Korea. As a result, the underpass structure can be forced by buoyancy, and therefore the in-situ buoyancy anchor method is usually being applied to prevent the uplifting force. For the Yeongjongdo sky city project, the drainage method was applied to remove the buoyancy force. In this study we estimate the efficiency and safety of the applied design and propose the detailed guidelines for standard design and maintenance of the guided drainage technique. Especially, the auxiliary pumping well was operated to maintain the ground water level around the underpass. In the study site, the applied guided drainage method has advantages in both engineering and economic aspects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.67-74
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• 2021

Domestically, technical condition evaluation for breakwaters has been conducted through safety checks and safety diagnosis. If necessary, maintenance for the facility is conducted. However, in recent years, the need for infrastructure management has been increasing from a life-cycle-cost perspective. For these reasons, the "Sustainable Infrastructure Management Basic Act" was enacted. Previously, only the technical part of the breakwaters was evaluated. However, based on the act, comprehensive management of breakwaters will be possible through performance improvement by adding economic and political evaluations. In this study, evaluation factors and evaluation methods were developed for a breakwater rehabilitation project. The purpose of this study is to present a development direction, items, and methods for the evaluation of breakwater performance improvement to be applied in future practice. This study reviews the concept of maintenance and performance improvement, the literature related to performance improvement, and the project type for the common standard of performance improvement. Evaluation items and evaluation methods for breakwater rehabilitation are suggested to be reviewed by experts. The methodology suggested in this study could be used for preventive maintenance and to reduce accidents.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.4
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• pp.86-93
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• 2010

The wear of railway track affects loss of rough ride, noise or vibration of train and traveling safety. Moreover as the track is worn away, this promotes destruction of structural mechanism of rail track which can bring about increasing of rail track maintenance cost drastically. For this reason, it is very important and interested research subject to design railway track structure and to analyse train movement mechanism based on systematic analysis of the reasons causing rail wear possible in real field. In this research, for the efficient maintenance, Life Cycle Performance of rail track and maintenance characteristics are computed considering some track components such as track type, contracting type, sleeper type and roadbed type. Time - Wear probabilistic distribution relationship as well as multiple regression analysis based on time, curvature and wear data are computed to predict the service life remainder of railway track and to be adapted to safety assessment.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.639-640
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• 2008

최근 개발이 활발한 IT 기술 중 웹 기술을 응용하여 여러 가지 산업 기기와 그 부품들에 대하여 상태의 온라인 감시에 기반을 둔 진단 및 유지보수 등을 통합적으로 관리 할 수 있는 시스템의 개발에 관하여 소개하였다. 지능화되고 복잡해지기 쉬운 현대의 다양한 유지보수 기법들의 개발이 완료된 후, 기존 시스템의 통합과 사용법 숙지 등의 어려움으로 시너지 효과가 발휘되지 않는 문제점을 극복하고 다양한 사용자들을 위한 원격응용이 가능할 것이다.