• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.5-8
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• 2006

In this study, various fundamental experiments including durability and time-dependent deformation are performed to compile a database for a utilization of high-strength concrete for PSC bridges. In the mix design, concrete strength at early age when prestressing forces are introduced to the PSC member and slumpflow suitable for pumping of concrete are considered to make a concrete fit for PSC bridges. The main parameters investigated are the kinds and replacement ratios of mineral admixtures and low-heat cement. Experimental tests on durability include penetration of chloride ions, freezing-thawing, combined deterioration, and simple adiabatic temperature rise test. In addition, time-dependent deformation such as creep, drying and autogenous shrinkage, which is particularly important factor in the design and construction of PSC bridges, is tested and analyzed.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 2001년도 추계 컨퍼런스: 인터넷 비즈니스 환경에서의 디지털 컨텐츠 기술 발전 및 활용을 위한 컨퍼런스
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• pp.536-554
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• 2001

인터넷 이용자의 증가와 멀티미디어 등 대용량 콘텐츠에 대한 수요의 증가로 인해 데이터 트래픽은 기하 급수적으로 늘어나는 데 비해 네트웍 성능향상에 대한 투자는 이에 미치지 못함으로서 결과적으로 인터넷은 트래픽의 병목현상, 즉 정체현상이 발생하게 되었으며 점차 그 정도가 심해지고 있다. 이 문제를 해결하기 위해 제안하는 방안이 바로 전략적 CDN(Content Delivery Network) 이다. 현실적으로, 본 연구는 물리적인 망 증설만으로는 트래픽 체증 문제를 해결하기는 어려우므로 주요 ISP 네트웍에 전략적 캐시서버를 설치하여 CP의 콘텐츠를 각 ISP 네트웍마다 분산하여 저장하고 이용자의 요청 시 이용자의 인터넷 회선이 물려 있는 ISP 네트웍에서 바로 콘텐츠를 전송하여 데이터 손실과 속도 저하 등의 문제를 해결하는 CDN의 구성과 그 효과를 실증적으로 밝혔다.

• 정보기술과데이타베이스저널
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• 제8권2호
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• pp.41-60
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• 2001

Despite the growth in Internet users, demand for multi-medial, large data files and resulting explosive growth in data traffic, there has been lack of investment in Middle-Mile, interconnection of various networks, resulting in bottleneck effect, which is acerbating. One strategy to overcome such network bottleneck is Content Delivery Network (CDN). CDN does not achieve efficient delivery of large file data through physical improvement/increase in network capacity, but by delivering large file contents, the cause of bottlenecks, from distributed servers. Since it is impracticable to physically improve networks capacity to accommodate the growth in internet traffic, CON, by strong CPs contents at cache servers deployed at major ISPs networks, is able to deliver requested contents to the requesting Web clients without the loss of data and long latency.

• 한국정보통신학회논문지
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• 제13권5호
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• pp.931-936
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• 2009

분류의 문제는 데이터 베이스 시스템에서 기록을 그룹화, VLSI 회로에서 결함을 찾는 것이나 이미지 프로세싱 등에서 중요한 역할을 하고 있다. 이 논문에서는 주어진 패턴 집합을 부분공간의 개념을 이용하여 최소의 메모리량을 갖는 분류기로써의 D1-MACA를 구성하는 알고리즘을 제안한다. 또한 attractor의 수가 2개가 되게 D1-MACA를 구성할 수 있는 패턴 집합의 조건을 분석한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.239-240
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• 2010

본 연구에서는 변형경화형 시멘트 복합체(SHCC)에 섬유 혼입율을 변수로 실험체를 제작하여 역학적 특성을 평가하였으며, 실험 결과로부터 향후 SHCC의 관한 연구의 기초자료를 제시하고자 한다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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• pp.305-312
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• 2003

Recently, with a progressive development of hardware of computer, the internet and network technology, the environment of construction varies rapidly due to increase the complex form in structure shape and system. With variations, the CAD system for design and products also varies from 2D system to 3D system. This study mainly deals with the methodology of automatic connection design of 3D CAD system, steel connection system (XSteel) using macro. First, using design program in the steel connection system, Xsteel, the joint connection macro will be made up and established the detail classes of design. The next, Database Program (Converter Program) related to the general structural analysis program (MIDAS) and the steel connection program (Xsteel) is constructed for data interface between two programs. From this study, if the merits of 3D CAD system and converter program are utilized well, it is expected that the time needed in modeling and the amounts due to material loses decrease gradually.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.508-513
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• 2006

In construction of RC buildings, the quality of shop and detail drawings is very essential for the quality and safety of buildings. Nevertheless, most of thess works are left to site workers and the requirements about bar detailing such as anchorage and splice have been done without rational design and engineering. The purpose of this research is to develop a computer-aided drawing system of rebars for RC buildings. The system is based on an integrated structural design system, that is SDP. SDP manages an engineering database for structural design information. It provides all the information needed to draw rebar drawings. The drawing system consists of three modules, 1) Structual Plan Drawing System, 2) Shop Drawing System, and 3) Detail Drawing System. It is expected that not only the productivity of detail drawing works but also the quality and safety of buildings will be improved using the rebar drawing system developed in this research.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.574-580
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• 2005

Recently, the number of bridges and tunnels in railway is increasing due to the super high-speedy of train. Also, because of successively accidents of civil structures such as bridges and dams, the importance of maintenance become influential. The purpose of this study is to show the probabilistic life cycle cost analysis technique(PLCC) of the railroad bridge as pubic-infrastructures, and reasonably to indicate the economy in life cycle cost(LCC) through a case study. Rationally for life cycle cost analysis, the data gathered through many materials considered the uncertainty such as covariance. As a result, it is indicated that prestressed concrete bridge is pretty more cost-effective during life-cycle than preflex as well as steel box bridge. In future, if the construction of database and maintenance materials for railroad infrastructure is actualized, the life cycle cost analysis for railroad can be conducted easily and practically.

• 한국철도학회논문집
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• 제3권3호
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• pp.139-146
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• 2000

Recently, many kinds of research have been actively developing for a standardization and information to the field of design, construction, supervision, maintenance and management on facilities. The establishment of standard classification system on tunnel facilities and inspection data is most important among the things to have a efficiently maintenance and management. This paper suggests standard classification system on tunnel facilities and inspection data, and, on the basis of that, code work with standard classification system and input work was practised. The purpose of this paper is to suggest a kind of statistics data and investigate a characteristics of inspection using statistic data on railway tunnel.

• 한국공간정보시스템학회 논문지
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• 제2권1호
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• pp.83-90
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• 2000

최근 인터넷의 발달로 GIS 관련 연구분야도 지금까지의 GIS 정보구축분야에서 구축된 정보에 대한 활용을 위한 정보유통분야로 관심이 집중되고 있다. 이에 본 논문에서는 GIS 유통구조에 대한 표준화동향을 살펴보고, 국내 GIS 분야에서 현재 사용되고 있는 데이터들을 분류하여 GIS 전문가 설문조사를 통하여 데이터별 보안요구를 조사하였다. 이를 바탕으로 현재 국내에서 진행중인 암호 및 인증을 위한 공개키기반 구축사업과 연계하여 GIS 정보의 안전한 전송과 접근제어를 위한 보안방안을 제시한다.