• 한국자동차공학회논문집
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• 제1권1호
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• pp.66-79
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• 1993

To construct the design back data for a lean-burn gas engine, we have designed a constant volume combustion chamber with sub-chamber. With constant volume ratio of main-sub combustion chamber and constant equivalence ratio of methane-air mixture, the influence of geometric configurations(diameter, injection angle, number, length) of passagehole upon combustion characteristics were studied. It was found that combustion characteristics in the main combustion chamber were greatly influenced by the injection angle and length of passagehole.

• 수산해양기술연구
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• 제48권3호
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• pp.277-283
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• 2012

The characteristics of abrasive wear on sliding speed of glass fiber reinforcement (GF/PUR) composites were investigated at ambient temperature by pin-on-disc friction test. The cumulative wear volume, friction coefficient and surface roughness of these materials on sliding speed were determined experimentally. The major failure mechanisms were lapping layers, deformation of resin, ploughing, delamination, and cracking by scanning electric microscopy (SEM) photograph of the tested surface. As increasing the sliding speed the GF/PUR composites indicated higher friction coefficient. The surface roughness of the GF/PUR composites was increased as the sliding speed was higher in wear test.

• 수산해양기술연구
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• 제49권4호
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• pp.492-499
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• 2013

The characteristics of abrasive wear of the rubber matrix composites filled with nano sized silica particles were investigated at ambient temperature by pin-on-disc friction test. The range of volume fraction of silica particles tested are between 11% to 25%. The cumulative wear volume and friction coefficient of these materials on particle volume fraction were determined experimentally. The major failure mechanisms were lapping layers, deformation of matrix, ploughing, deboding of particles and microcracking by scanning electric microscopy photograph of the tested surface. The cumulative wear volume showed a tendency to increase nonlinear with increase of sliding distance. As increasing the silica particles of these composites indicated higher friction coefficient.

• 한국산업융합학회 논문집
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• 제2권1호
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• pp.121-130
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• 1999

It is necessary to measure pressure, temperature, chemical equilibrium and the shape of flame in order to understand the combustion process in a combustion chamber. In particular, the flame formulation and combustion process of divided combustion chamber are different from those of a single chamber, And the variable diameter of a jet hole can effect not only physical properties like ejection velocity, temperature and time of combustion but also a chemical property like the reaction mechanism. Accordingly temperature is one of the most important factors which influence the combustion mechanism. This paper observed shape of flame by using the schlieren photographs and measured the pressure in a combustion chamber and the reaching time of the flame by ion probe By doing these, we investigation the formulation of the flame and the process of propagation. These measurement methods can be advanced in understanding the combustion process and process and propagation of flame.

• 한국인쇄학회지
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• 제21권1호
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• pp.35-44
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• 2003

Because of computer developing, the digital image making the use of many a field of application with - web-above, electronic publishing. printing, dynamic image management and photo CD production etc., however many problems of save and management. The management image use of compression moth which don't have a affect on image, reduce file size. A study used sequential DCT0based mode and progressive DCT-based mode of JPEG(Joing Photographic Experts Group) compression method and Wavelet compression method. Therefore, the analog image and digital image was changed and applied by several stages according to compression rate. It made inquiries of the optimum compression rate that be compared quality transformation between original image and compressed image. As compression image was printing simply, the quality was studied by subjective valuation method, that was studied propriety and usefulness.

• 오토저널
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• 제12권5호
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• pp.76-84
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• 1990

To study diesel fuel spray behavior, an experimental study was undertaken to investigate injection characteristics in vary ing back pressure and atomization mechanism in a non-evaporating diesel spray. Generally, injection characteristics is the curve of fuel flow plotted against time. The area under this curve is equal to the total quantity of fuel discharged for one injection. The method that measures rate of injection is long tube-type fuel rate indicator. Diesel spray injected into a quiescent gaseous environment under high pressure is observed by taking high speed camera by the focused shadow photographs. The results show that, at the start of injection, as the injected fuel rushes into the quiescent atmosphere the spray angle becomes large. Finally the spray stabilizes at a constant cone angle. Spray penetration length increases with the injection pressure.

• 한국안광학회지
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• 제5권1호
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• pp.39-42
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• 2000

눈을 통한 3차원의 입체시(stereopsis)는 좌 우 눈으로 들어오는 상의 융합에 의해 형성된다. 양안시차(Binocular disparity)의 깊이 감각을 유발시킴으로써 3D-Stereogram를 만들 수 있다. 구형 물체와 눈의 3D-Steregram은 양안시차의 시야각에 대응하는 조명 위치각으로 촬영하여 만들었고 입체시가 됨을 규명하였다.

• 한국응용과학기술학회지
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• 제23권1호
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• pp.92-97
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• 2006

In this paper, magenta coupler was prepared by the reaction of 1-(2,4,6-Trichlorophenyl)-3-(5-amino-2-chloroanilino)-5-pyrazolone with 2,4-di-tert-pentyl-phenoxy butanoyl chloride in the presence of pyridine. The product was identified by using various analytical tools such as melting point, elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer and GC-mass spectrometer. The reaction of magenta coupler with CD-3 (color development agent) was shown magenta color.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1991년도 추계학술대회 논문집
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• pp.24-26
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• 1991

Identification of the cause of electrically related fire accident may be approached either by studying accident related electric properties or by investigating power instruments at the site of the accident. In the present paper, the former approach is taken especially on investigating the consequences of excessive current induced by electric short circuiting of high power instruments which is reported as the primary cause electricity related fire accidents. In order to provide reliability of the identification method, microscopic photograph's are taken for the cross sections of the electric wires after being exposed to over current and heated by external means, respectively The results are consequently compared and analysed.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 춘계학술대회 논문집
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• pp.88-91
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• 2007

국립산림과학원 산림조사과에서는 지식정보화사업의 지원 하에 남한 전체 낱장/정사항공 사진 영상 DB툴 구축하고， 항공사진검색시스텀 (aerophoto.kfri.go. kr)을 개발하여 대국민 인터넷 서비스를 제공하고 있다. 본 논문에서는 5TB 대용량 항공사진 원본 영상과 메타자료를 웹 지리정보 서비스에 적합하도록 자료의 변환 방식，소프트웨어와 하드웨어의 최적 구성안, 그리고 응용 검색 시스템의 개발 기능을 소개 한다. 또한，항공사진 웹 검색 시스템은 벡터 지리정보와 항공사진 영상을 각각 전송하여 융합하고 분석하는 기능을 담당하는 클라이언트 모듈을 한정된 네트워크 환경에서 대용량 자료의 검색 속도 향상을 위하여 비동기식 처리 방식으로 개선하였다. 그리고 국가 지리정보 인프라인 정사항공사진 자료를 타 시스템과 연계 활용하기 위한 방안으로 ESRI ArcGIS 의 Plug-in 적용 사례를 제시한다.