• Title/Summary/Keyword: breakdown structure

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Analysis of Classification for Maintenance Management in Urban Transit Facility (도시철도 보선시설물 유지관리를 위한 표준 분류체게 연구)

  • Park, Seo-Young;Shin, Jeong-Rul;Park, Ki-Jun;Kim, Gil-Dong;Han, Seok-Yun
    • Proceedings of the KSR Conference
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    • 2003.10b
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    • pp.448-453
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    • 2003
  • Most urban transit companies recognize the necessity of classification for facility management Classification for urban transit facility is necessary for standardization of maintenance management. The practical application. however. is not easy because of the absence of standardization of classification for urban transit facility and the difficulty in objectification of breakdown structure. This study suggests a proposal of classification for maintenance management in urban transit facility. This study defines standardization of classification as facility, work, maintenance and attribute to manage urban transit facility. And attribute classification consist of material, equipment and document. The suggested classification can be used as a useful maintenance management tool that enables evaluation of urban transit facility by standardization. The results of this study could be used as references for related urban transit companies.

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Procedure Development for Organizing Electronic Technical Manual of Construction Design Information and Applicability Analysis for Practical Project (건설공사 설계도서매뉴얼의 전자화 절차구성 및 실무 적용효과 분석)

  • Kang, Leen-Seok;Moon, Hyoun-Seok;Kwak, Joong-Min
    • Journal of the Korean Society for Railway
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    • v.10 no.2 s.39
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    • pp.103-111
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    • 2007
  • The existing design materials by document type are restricted in searching and acquiring necessary design information because the materials consist of huge information and various document types. This study suggests a methodology to develop an electronic technical manual that can manage construction design materials by XML-base integrated information system. Electronic technical manual for design materials can provide visualized information through various multimedia tools such as multi-link, virtual reality and animation. Using an integrated electronic manual for construction project can prevent to miss necessary design information. The results of this study includes a data flow diagram to develop an interactive electronic technical manual (IETM) for construction design information. Finally the study suggests some scenarios for practical use and quantitative analysis of application effect analysis by AHP method.

Quantitative Analysis of the Structure and Behavior of Imports in Korea

  • Shin, Hwang-Ho
    • Journal of the Korean Statistical Society
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    • v.4 no.2
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    • pp.127-138
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    • 1975
  • There have been a number of studies and analysis designed to explain imports and exports disaggregated by commodities in many countries. These analyses, however, all concentrate on the trading patterns of industrial countries, and there has been very little of systematic analyses of the imports and exports by types of commodities for developing countries. There is, of course, an obvious reason for ignoring these countries, and that has to do with the availability, or rather paucity, of adequate data; it is widely known that the data on prices of disaggregated imports and exports are most difficult to obtain. The purpose of this paper is to study and analyze the behavior of the imports of Korea at disaggregated levels during the period 1965-1974. Data on imports at a disaggregated level have recently been made available in Korea for a seven-commodity breakdown. These seven categories cover some 90% of the total Korean imports.

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CVD로 성장된 다결정 3C-SiC 박막의 전기적 특성

  • An, Jeong-Hak;Jeong, Gwi-Sang
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2007.06a
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    • pp.179-182
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    • 2007
  • Polycrystaline (poly) 3C-SiC thin film on n-type and p-type Si were deposited by APCVD using HMDS, $H_2$, and Ar gas at $1180^{\circ}C$ for 3 hour. And then the schottky diode with Au/poly 3C-Sic/Si(n-type) structure was fabricated. Its threshold voltage ($V_d$), breakdown voltage, thickness of depletion layer, and doping concentration ($N_D$) value were measured as 0.84 V, over 140 V, 61nm, and $2.7{\times}10^{19}\;cm^3$, respectively. The p-n junction diode fabricated by poly 3C-SiC was obtained like characteristics of single 3C-SiC p-n junction diode. Therefore, its poly 3C-SiC thin films are suitable MEMS applications in conjuction with Si fabrication technology.

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A New Model on Integration of Feasibility Estimates for Designing FEIT System in R & D Project (R & D 프로잭트의 Feasibility 추정 시스템설계를 위한 추정치 종합화 모형의 구축)

  • 권철신
    • Journal of the Korean Operations Research and Management Science Society
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    • v.15 no.1
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    • pp.47-61
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    • 1990
  • The purpose of this study is to construct a new model named Communication Consensus Value Weighted (CCVW) model based on inter-personal technical communication within a project team, and to design Feasibility Estimates Integrated Terminal System (FEITS) which is a subsystem of R & D Project Planning System/System Alternatives Feasibility Estimation System (RDPPL/SAFES) using the model as a key function for feasibility estimation in that system. This new model aims to integrate technical feasibility estimated by several estimators in the lowest level as the project work breakdown structure which is the indentical conception of a terminal system in RDPPL. The process to obtain the feasibility estimate integrated is presented in this paper.

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Electrical Properties of Silicon Nitride Thin Films Formed (ECR 플라즈마에 의해 형성된 실리콘 질화막의 전기적 특성)

  • 구본영;전유찬;주승기
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.29A no.10
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    • pp.35-41
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    • 1992
  • Ultra-thin silicon nitride films were fabricated with ECR(Electron cyclotron Resonance) nitrogen plasma at room temperature. Film thickness was about 50$\AA$ after nitridation for 1min at microwave power of 1000W, RF power of 500W, and NS12T pressure of ${\times}10^{-3}$ torr. 50$\AA$ fo nitride film was grown within 1 min and no appreciable growth occured thereafter. Dielectric breakdown strength and leakage current density in Al/SiN/Si structure were measured to be about 7-11 MV/cm and ${\times}10^{-10}~5{\times}10^{-10}A/cm^{2}$, respectively. Observed linear relationship in 1n(J/E)-vs-E$^{1/2}$ and no polarity-dependence of the leakage current indicated that the Poole-Frenkel emission is mainly responsible for the conduction in this nitrided silicon films.

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Thermal treatment effect of $CaF_2$ films for TFT gate insulator applications

  • Kim, Do-Young;Park, Suk-Won;Junsin Yi
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1998.06a
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    • pp.145-148
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    • 1998
  • Fluoride({{{{ { CaF}_{2 } }}}}) films exhibited a cubic structure with similar lattice constant to that of Si and have sufficient breakdown electric field as gate dielectric material. Therefore, {{{{ { CaF}_{2 } }}}} are expected to replace conventional insulator such {{{{ { SiO}_{ 2},{Ta}_{2}{O}_{ 2} and{Al}_{2}{O}_{5}. However, {CaF}_{2}}}}} films showed hystereisis properties due to mobile charges in the film. To solve this problem we performed thermal treatment and achieves field. C-v results indicate a reduced hystereisis window of {{{{ }}}}ΔV =0.2v, LOW INTERFACE STATE {{{{{D}_{it}=2.0 TIMES {10}^{11}{cm}^{-1}{eV}^{-1}}}}} in midgap, and good WIS diode properties. We observed a preferential crystallization of(200) plane from XRD analysis. RTA treatment effects on various material properties of {{{{{CaF}_{2}}}}} are presented in this paper.

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Establishment of Building Work Section of LH Guide Specifications (건축부문 LH 전문시방서 작성 방안)

  • Oh, Eun-Ho;Kim, Tae-Song;Lee, Kab-Won;Koo, Jai-Dong
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.11a
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    • pp.177-179
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    • 2011
  • The difference the guide specifications of between housing and land development has been caused many problems, since Korea Land Corporation and Korea Housing Corporation were merged into LH (Land and Housing Corporation) in 2009. Those are that specification criteria to establishing lower level specifications are disordered; duplicated investment on sites; management systems are conflicted site to site, which are based on different operation system from old land and housing corporations, etc. Thus, this paper aims to suggest a direction of integrated guide specification system of LH including improved and advanced classification hierarchy and specification.

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Information Modeling of Modular Bridge Pier using BIM Based 3D-Model Library (BIM 기반 3차원 모델 라이브러리를 통한 모듈러 교각의 정보모델링)

  • Jo, Jae-Hun;Kim, Dong-Wook;Lee, Kwang-Myong;Nam, Sang-Hyeok
    • Journal of KIBIM
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    • v.3 no.4
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    • pp.11-18
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    • 2013
  • Modular technology has become a major issue of the construction industries to enhance their productivity. Modular bridge construction generally requires the collaboration between the contractor, designer, fabricator and constructor. Therefore, a readily accessible information model based on BIM technology should be provided for their communication during a construction project life-cycle. In this study, BIM based 3D information modeling was carried out for the modular bridge pier. First, the product breakdown structure (PBS) and level of detail (LOD) of the pier were defined. Based on them, 3D models were created by using parametric modeling method. In addition, database was constructed for the exchange of geometry and property data of 3D models. Finally, application areas of 3D information model were suggested, including the quantity estimation and the 4D simulation.

Effects of Interfacial Conditions on Breakdown Strength of XLPE/EPDM Laminates (XLPE/EPDM의 계면조건이 절연파괴강도에 미치는 영향)

  • Choi, W.C.;Lee, C.J.;Jo, D.S.;Park, K.S.;Kim, J.S.;Han, S.O.
    • Proceedings of the KIEE Conference
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    • 1998.07d
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    • pp.1273-1275
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    • 1998
  • The main faults at cable joint are mainly originate from double layered structure, which is composed of different kinds of materials such as XLPE/EPDM laminatest. In this paper, to investigate the effect of interfacial condition and coagents on dielectric strength of XLPE/EPDM, we prepared XLPE/grease/EPDM, XLPE/grease + coagent/EPDM laminates. Dielectric strength of the XLPE/EPDM laminates pasted with the grease compounded crosslinking coagent (TMPTA, TMPTMA) is higher than that of the laminates paseted with the grease without coagent.

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