• 한국건설관리학회논문집
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• 제7권5호
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• pp.53-63
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• 2006

2005년부터 장부는 국민경제 선순환과 국민 삶의 질 향상이라는 목표 하에, 높은 수준의 공공서비스를 조기 또는 적기에 제공하기 위한 방책의 일환으로 BTL 사업의 시행을 추진하고 있다. 그러나 시행 초기부터 낮은 사업수익률, 사업제안 비용의 부담, 제도적 구조적 사업 진입 장벽으로 인한 지방 중소규모 건설업체의 불만 등 많은 문제점을 나타내고 있어 성공적인 BTL 사업에 걸림돌이 되고 있다. 이에 정부는 지방 중소업체의 참여율을 시공 비율 규정으로 정하고 사업성이 떨어지는 적정 이하 규모 공사를 BTL사업에서 제외하는 등의 대책을 세웠으나 근본적이 해결책으로서는 미흡한 것으로 조사되고 있다. 본 연구에서는 BTL 사업 추진 중 개선되어야 할 사항들에 대해서 문헌조사 및 전문가와의 심층 면담조사 등을 통해 조사 및 분석하였다. 본 연구 결과 가장 근본적인 개선사항으로 BTL 사업 수행 주체의 구성 방식이 시공자 중심으로 되어있는 DBFO(Design, Build, Finance, and Operate) 방식에 있음을 확인하고, 이러한 사업 수행 주체의 구성 방식을 재무적 투자자가 건설사업 관리자의 전문지식을 최대한 활용할 수 있도록 하는 FCDO(Finance, Construction Management, Development and Operate) 방식으로의 전환을 개선방안으로 제시한다.

• Restorative Dentistry and Endodontics
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• 제44권3호
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• pp.27.1-27.12
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• 2019

This case report describes a technique in which endodontic treatment and permanent indirect restoration were completed in the same clinical appointment with the aid of a computer-aided design/computer-aided manufacturing (CAD/CAM) system. Two patients were diagnosed with irreversible pulpitis of the mandibular first molar. After access preparation, root canals were located, irrigation was performed until bleeding ceased, and the coronal tooth structure was prepared for indirect restoration. Then, utilizing an interim 3-mm build-up of the endodontic access cavity, a hemi-arch digital scan was performed with an intraoral scanner. Subsequent to digital scanning, restoration design was performed simultaneously with the endodontic procedure. The root canals were shaped using the Race system under irrigation with 2.5% sodium hypochlorite followed by root canal filling. The pulp chamber was subsequently filled with a 3-mm-thick composite resin restoration mimicking the interim build-up previously utilized to facilitate block milling in the CAD/CAM system. Clinical try-in of the permanent onlay restoration was followed by acid etching, application of a 5th generation adhesive, and cementation of the indirect restoration. Once the restoration was cemented, rubber dam isolation was removed, followed by occlusal adjustment and polishing. After 2 years of follow-up, the restorations were esthetically and functionally satisfactory, without complications.

• 한국구조물진단유지관리공학회 논문집
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• 제23권5호
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• pp.30-36
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• 2019

염해에 노출된 콘크리트 구조물의 내구수명을 정량적으로 평가하기 위해서는 사용 배합을 통하여 확산계수를 평가하고 이를 이용한 염화물 침투 해석이 필요하다. 본 연구에서는 비말대에 노출된 콘크리트 구조물에 대하여 촉진 확산계수를 NT BUILD 492 및 ASTM 1202를 통하여 평가하였으며, 기존의 연구를 이용하여 겉보기 확산계수를 도출하였다. 사용배합의 특성과 가장 보수적인 조건인 임계 염화물량과 표면 염화물량을 고려하였으며, Life 365 ver.2 프로그램을 이용하여 외벽 및 기둥구조의 내구수명을 평가하였다. 10년 및 15년의 Built-up period의 변화에 대해서는 내구수명은 큰 차이를 보이지 않았으며. 슬래그를 사용한 두 개의 배합에서는 높은 시간의존성 지수와 낮은 초기 염화물 확산계수로 인해 75년 이상의 높은 내구수명이 확보되었다.

• 대한건축학회논문집:구조계
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• 제34권4호
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• pp.75-82
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• 2018

BIM(Building Information Modeling) based design process can initiatively conduct a task through all phases from early design step to construction and maintenance step. Also BIM efficiently manage the building's energy by reflecting 3D design and construction life cycle. This paper proposes an efficient process to build AHU's BIM-based library. This study involves analyzing an AHU model for development of design module, and making the template model using the same 12 parts including the shapes of ducts, doors and frames. In consideration of each shape's direction and the status of existence, which are detailed shapes of parts upon making the template model, all the shapes of the AHU model can be expressed. By applying parametric modeling to the template model, a quick and precise modification and transformation can be conducted, thus the efficiency is enhanced. A user selects an AHU model from a 2D model selection program, and extracts shape information. The final AHU shape is completed through the automation work of unnecessary shape deletion by bringing the extracted shape information to the template model. This enables the user to build efficient AHU's BIM-based library, since the quick and precise modification and transformation of the template model are possibile, and all AHU model shapes can be expressed.

• Journal of information and communication convergence engineering
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• 제1권3호
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• pp.163-168
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• 2003

This paper presents a cascade multilevel PWM rectifier without the isolation transformers for energy build-up at each inverter modules. The features and advantages of the proposed PWM rectifier can be summarized as follows; I) It realizes the high power high voltage AC/DC power conversion, 2) It uses no transformer which is bulky and heavy, 3) It has hybrid structure so that switching devices can be effectively utilized, 4) It produces high quality AC current even in high power high voltage applications, 5) The input power factor remains unity by simple modulation index control. The multilevel rectifier is analyzed by using the circuit DQ transformation whereby the characteristics and control equations are obtained. Finally, it will be shown that the system simulation reveals the validity of analyses.

• Fibers and Polymers
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• 제2권3호
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• pp.159-163
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• 2001

Five yellow disperse dyes were synthesized and their dyeing, fastness and photodegradation behaviors were investigated. It was found that dyes derived from phenylindole and N-alkylaminobenzene showed dye uptake directly proportional to the dye concentration, but the build-up of dyes derived from carbazole and pyridone were not good. The wavelength at maximum absorption. molar extinction coefficient. and the tendency to the photodegradation were strongly dependent on the electron donating ability of the coupling component. The dye, whose coupling component was phenylindole, possessed the excellent dyeing properties and the high degree of lightfastness. UVA had an effect on the inhibition of the photodegradation especially for the easily photodegradabte dyes.

• Water Engineering Research
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• 제2권2호
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• pp.103-112
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• 2001

Issues and problems in formulating South Korea's water resources policy are discussed in terms of water quantity and quality. South Korean needs both water conservation and water supply capability for the growing population and economic activities. The government has attempted to build more large-scale dams to store and supply water for residential, farming and industrial uses, but the environmentalists who emphasize conservation and environmental protection oppose the government. The environmentalists are popular among the general public. Water quality has been deteriorating from point- ad non-point sources. urban and farm runoffs are serious pollutants. All want by preserve water quality. There is no dispute on this matter between the government and the environmentalists. Money is hard to come by to preserve water quality. Economic and financial crises and no self-sufficient local governments' revenue structure are pessimistic. Basic survey on water resources, hydrology and hydraulic is badly needed for the future water resources planning.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 추계학술발표회 논문집
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• pp.347-352
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• 2003

This study attempts to develop the management and control system of water pipe on the footing of database builded by the research on the pipe of water supply equipped over 48.809km within district of Hamyang-up by Hamyang-Gun, and to apply it to the work of self-governing body. And, since the structure and equipment of facilities of underground water supply pipe ate so complex, the maintenance and management of function of facilities are needed for long-term. This study has the purpose to build the database per self-governing body which can be connected with the future NGIS project, and to promote the efficiency of management and control of facilities and equipment.

• 한국의류학회지
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• 제22권4호
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• pp.452-459
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• 1998

The purpose of this study was to discover a conceptual framework and evaluation process of apparel quality by means-end chain theory. The theoretical study was conducted to find out a conceptual framework and build a hypothetical evaluation process model of apparel quality. Apparel quality was perceived associative network called a means-end chain and was evaluated in several stages. A conceptual framework of apparel quality evaluation was organized into hierarchical relationships among four different dimensions: physical attribute, physical function, instrumental performance, and expressive performance. The means-end structure linked tangible physical attributes and function to more abstract instrumental and expressive performance. A hypothetical evaluation process model linked dimensions of apparel quality to the selected means-end relationship. Different consumers had different means-end chains for the same apparel. Therefore different subjects are likely to have different evaluation paths. From this study we can suggest an evaluation process model of apparel quality.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1743-1753
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• 2011

Seoul Metropolitan Government has performed alternative transit system, light rail transit(LRT), for settling the problems of urban public transit system based on conventional bus service and heavy rail transit(HRT). LRT projects of total 8 lines(about 73.6km), including Ui-Sinseol line, have been planned as Build-Transfer-Operate(BTO) projects. For the first LRT, Ui-Sinseol line, however, design of structure had met standard for design of HRT, because of no domestic design code for LRT when participates of Ui-Sinseol project submitted the design proposal. This case study reports a successful example of LRT design minimizing the scale of stations designed in base of HRT code. The problems, like oversized structures compared with LRT vehicles, excessive costs for construction, had been resolved through negotiations with the participates of Ui-Sinseol line. Result suggests that present and future costs for construction and maintenance of the LRT projects in Seoul be considerably reduced in advance.