• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.491-494
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• 2007

국제 고유가에 힘입어 최근 중동의 산유국 중심으로 신규 사업 잘주가 이어지고 있다. 플랜트 산업은 엔지니어링(Engineering)과 조달(Procurement), 시공(Construction)이 융합된 복합산업(EPC)으로 고부가가치 산업이다. 또한 조달부문이 전체 사업비 규모의 70% 이상을 차지하므로 구매조달의 성패가 사업의 성패로까지 이어진다. 그러나 해외에서 다양한 사업참여 주체에 의해 수행되는 사업특성 상 구매조달 업무흐름 전체를 파악하고 원활히 사업을 수행하기란 어려운 실정이다. 따라서 최근 구매 및 조달 업무의 합리화를 통한 이윤창출 노력이 이어지고 있다. 본 연구에서는 해외 프로젝트를 수행하는 국내 주요 건설회사의 기존 구매조달 업무프로세스를 조사${\cdot}$분석하여 적정프로세스를 도출하였다. 또한 업무 프로세스상의 정보 및 문서의 입출력 정보를 분석하였다. 본 연구의 결과는 향후 해외 사업에 참여하게 되는 신규 업체의 인력 교육과 실무 활용에 이해를 도울 수 있는 자료로 활용될 수 있을 것으로 기대하며, 구매조달 업무 시스템 개발을 위한 자료로 활용될 수 있을 것이다.

• 한국해양공학회지
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• 제31권6호
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• pp.425-430
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• 2017

In order to reduce the cost of corrections and time needed for the block assembly process, the reverse setting method is applied for a back-heated block to neutralize deck deformation. The proper reverse setting shape for a back-heated block to correct deformation improved the deck flatness, but an excessive amount of reverse setting could inversely affect the flatness of the block. A prediction method was developed for the proper reverse setting shape using a back-heated block, considering the complex geometry of blocks, thickness of the deck plate, and thermal loading conditions such as welding and back-heating. The prediction method was developed by combining the re-meshing technique and inherent strain-based deformation analysis using the finite element method. Because the flatness deviation was decreased until the lower critical point and thereafter it tended to increase again, the optimum value for which the flatness was the best case was selected by repeatedly calculating the predefined reverse setting values. Based on this analysis and the study of the back-heating deformation of large assembly blocks, including the reverse setting shape, the mechanism for selecting the optimum reverse setting value was identified. The developed method was applied to the actual blocks of a ship, and it was confirmed that the flatness of the block was improved. It is concluded that the developed prediction method can be used to predict the optimum reverse setting shape value of a ship's block, which will reduce the cost of corrections in the construction stage.

• 설비공학논문집
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• 제24권1호
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• pp.70-76
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• 2012

The purpose of this study is to analyze of the operating characteristics of the Gas engine driven Heat Pump(GHP) and to reduce maintenance costs through the most Economical plan. As the zoning modifications that have economic effects were confirmed. Applications should be made with a similar purpose of the space. The combination of a modified space has led to reduced operating hours of the outdoor unit. The reduction of the outdoor unit operating hours, reducing maintenance costs accordingly. When analyzed at six years have elapsed, the amount of savings through zoning modifications is more than an additional construction cost. During the design phase, cost-effective operation of the GHP is required for the proper zoning plan.

• 한국환경복원기술학회지
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• 제11권1호
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• pp.62-71
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• 2008

Recently, the expansion of housing developments has reduced green areas in cities. The reduction of green areas caused many negative effects on human beings. For functional improvement of ecosystem, government focuses on artificial ground greening because it gives improving microclimate and saving energy consumption. This research aims to develop the system to support decision making of greening for artificial ground greening. This system consist of rooftop greening, wall greening, and street greening system which can suggest proper type of greening and calculate the effect of the greening considering the proponents inputs. It presents social, economic, and ecological value such as cost, energy saving, and temperature reduction. As it is web-based system users can easily access with internet. This system provides automatic selection modes.As a result, with this developed web-based system, decision makers can evaluate the effect of artificial ground green easily and the support to such movement will increase.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2120-2121
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• 2011

현재 정부가 추진하고 있는 전기분야 실적공사비 적산제도와 관련된 최근의 움직임은 당초의 취지와 달리 실적공사비에 대한 개념 부족과 임의적 해석 등으로 실적공사비 적산제도 도입의 바람직한 방향성에도 불구하고, 실적단가 축적의 기초 자료인 계약내역서의 직접 공사비 낙찰률 적용 관계 등 실적단가의 적정성에 대한에 근본적인 접근보다 예산절감, 물가안정 측면으로 접근하여 시장단가 반영에 대한 왜곡현상이 발생 할 수 있는 제도상의 문제점으로 실적단가 축적에 대한 적정성 판단에 따른 실적단가의 보정 수단이 미약하여, 현행 법제도 하에서 실적단가의 적정성 확보를 위한 대응 방안을 제시하여 실적공사비를 정착시킬 필요가 있다. 왜냐하면 품셈에 의한 문제점 등으로 실적공사비 적산제도로 공공 건설공사의 예정가격산정 방식을 전환 하였다고 볼 때, 본 제도의 실패는 또 다른 제도로의 전환 또는 보완이 필요하다고 판단된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권4호
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• pp.1911-1930
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• 2017

Overlay routing has emerged as a promising approach to improve reliability and efficiency of the Internet. The key to overlay routing is the placement and maintenance of the overlay infrastructure, especially, the selection and placement of key relay nodes. Spurred by the observation that a few relay nodes with high betweenness centrality can provide more optimal routes for a large number of node pairs, we propose a resilient routing overlay network construction method by introducing Super-Relay nodes. In detail, we present the K-Minimum Spanning Tree with Super-Relay nodes algorithm (SR-KMST), in which we focus on the selection and connection of Super-Relay nodes to optimize the routing quality in a resilient and scalable manner. For the simultaneous path failures between the default physical path and the overlay backup path, we also address the selection of recovery path. The objective is to select a proper one-hop recovery path with minimum cost in path probing and measurement. Simulations based on a real ISP network and a synthetic Internet topology show that our approach can provide high-quality overlay routing service, while achieving good robustness.

• 한국강구조학회 논문집
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• 제18권2호
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• pp.181-189
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• 2006

본 연구는 FSM 공법의 PSC 박스 거더교를 최소경비로 자동 설계하는 최적설계 프로그램을 이용하여 곡률마찰계수와 파상마에 대한 적정한 긴장재의 종류를 찾아내고 향후 긴장재의 연구 개발 방향을 제시하였으며, 사용되는 재료의 강도증진에 대한 연구방향을 제시하는데 본 연구의 목적이 있다. 사용된 최적설계 프로그램은 축차 무제약 최소화 기법을 이용하였고, 설계과정에서 설계점들이 설계가능 영역밖에 있는 것을 허용할 수 있도록 Kavlie가 제안한 확장 벌칙함수를 도입하였다. 또한 설계점들의 탐사 방법은 Powel's direct search method를 사용하며, 설계시간을 단축시키기 위해 설계점 변화에 따른 단면력 변화를 Gradient를 이용하여 근사화 시키는 방법을 사용하였다.

• 대한건축학회연합논문집
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• 제20권6호
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• pp.1-8
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• 2018

In generally, the estimation work regarding building mechanical service system in comparison with other architectural estimations is time-consuming, and the process is continuously getting more difficult because of the increased usage of the attached piping materials such as fittings and supports in addition to their complicated construction processes. In order to improve this problem, the Korean authority provides a simple method to estimate the attached material rate regarding the main piping material, which is the most time-consuming work in the architectural mechanical estimation. However, to be an applicable method on construction site, a proper conversion rate of the attached piping material is still required for the proposed method regarding building usage and working types. Therefore, the purpose of this research is the suggestion of the material and labor cost rate of the attached piping materials such as the fittings and supports by work types and fitting methods of indoor fire, sprinkler, and extinguishing gas piping work of mechanical fire protection facilities in office buildings that have been designed after 2010.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.830-833
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• 2004

Hydraulic structures have been constructed with low cost concrete so as to increase the investment efficiency. But, it has caused to produce structures having excess internal voids inside concrete. As the construction of agricultural irrigation and drainage project is concentrated on off-farming season and scattered in wider area, variation of quality of structures is big and it caused increase of internal voids. Due to that reason, hazardous substance is passing rather freely through the voids causing occur of crack and accordingly life time of structures is getting shortened. It is necessary to make a thesis of design criteria for design strength to increase life time, range of variation of quality, strength of ready-mixed concrete proper to design strength, and water-cement ratio and air content.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.119-121
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• 2004

This paper presents a methodology which can make alternatives of distribution system, and can calculate reliability costs, harmonics costs, and construction costs. And by using total cost of the system, decision maker can select the most economic and reasonable alternative. As a result, not only we can decide most economical and reasonable result, but we can get proper reliability and harmonics level. The usefulness of the method is verified by applying it to the test system.