• Journal of Photoscience
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• 제7권2호
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• pp.45-46
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• 2000

The polyoxyethylene compounds were added into the photographic emulsion during the physical ripening of photo sensitive silver halide crystal in this emulsion. The polyoxyethylene compounds improved the photographic properties of the film to a great extent increasing the photo sensitivity and decreasing the fog density.

• Journal of Photoscience
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• 제3권2호
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• pp.65-69
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• 1996

In this paper, it was studied about the red-sensitive layer. UV-Vis data of the dye at monomeric and J-state were considered with respect to their performance(contrast, density and fog) in photographic emulsion. The sensitizing effect of the dye is found to be strongly structuredependent. Naphthothiazolo carbocyanine dye can be used as red-sensitizing dye for the spectral sensitization of photographic emulsion.

• 한국응용과학기술학회지
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• 제20권4호
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• pp.366-371
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• 2003

In this paper, it was studied about the red-sensitive layer. UV-Vis data of the dye at monomeric and J-state were considered with respect to their performance(contrast, speed, density and fog) in photographic emulsion. The sensitizing effect of the dye is found to be strongly structure-dependent. Naphthctbiazolo carbocyanine dye can be used as red sensitizing dye for the spectral sensitization of photographic emulsion.

• Journal of Photoscience
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• 제6권3호
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• pp.85-90
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• 1999

Supramolecular photochemistry is concerned with systems where non-covalent interactions become significant or dominate in determining the chemistry of guest/host systems. The photocycloaddition of diaryl compounds and the photosensitized oxidation of alkenes included in zeolites, low-density polyethylene films and Nafion membranes is the subject of this report.

• 천문학논총
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• 제8권1호
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• pp.47-66
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• 1993

The Automated Eichner Iris Photometer(AEIP) at the Korea Basic Science Center was tested for its function and the proper procedure for photographic photometry. The AEIP requires about three hours for reaching the electrical stability. When the iris is controlled automatically, the repeatability of density unit (DU) is accurate in the uncertainty of ($0.0028{\sim}0.0048$)DU. The iris reading is found to be accurate within the mean error of $0.^{m}05$, which could be reduced to $0.^{m}02$ by the manual control. To check the applicability of the AEIP. each two photographic plates for UBV colors which were taken by Dupuy and Zukauskas(l976) for the open cluster Byur 2, were measured by using the AEIP. and the photographic magnitudes and colors of the stars in Byur 2 were determined. discussing the previous results.

• 대한방사선기술학회지:방사선기술과학
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• 제28권4호
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• pp.301-306
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• 2005

목 적 : 일부지역에서 실시되고 있는 유방촬영술에 대한 유방팬톰영상을 분석하여 화질관리의 실태를 알아보고져 한다. 대상과 방법 : 2005년 5월에서 6월까지 2개월간 일부지역의 47개 병원에 설치된 유방촬영기기를 대상으로 실험하였으며 유방팬톰영상의 분석은 확대경을 이용하여 영상에서 보이는 섬유소, 작은 석회화그룹, 종괴의 개수를 세어 점수로 기록 평가하였다. 유방팬톰영상평가시험의 평가기준에 의해서 섬유소 4개 이상, 작은 석회화그룹 3개 이상, 종괴 3개 이상이 보인 경우를 합격으로 분류하였다. 결 과 : 유방팬톰영상 47예 중 합격이 33예(70.3%), 불합격이 14예(29.7%)였으며 합격한 경우에 사용한 관전압 범위는 $23{\sim}30\;kVp$, 관전류량 범위는 $20{\sim}60\;mAs$, 사진농도 범위는 $0.48{\sim}1.77$로 나타났으며 격자를 사용한 경우는 31예(91%)로 나타났다. 결 론 : 일부지역에서 실시되고 있는 유방촬영술의 영상에서 약 70.3%가 유방팬톰영상평가 시험에 합격한 것으로 나타났다. 적절한 범위의 관전압, 관전류, 격자 사용으로 적절한 사진농도를 얻어 시험기준에 합격된 우수한 화질의 유방영상을 얻어야 한다.

• 한국인쇄학회지
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• 제20권1호
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• pp.133-145
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• 2002

전자사진은 디지털 기술의 급속한 발전에 의하여 그 응용 범위가 확대되고있으나, 은염사진과 원리와 특성이 근본적으로 다르며 은염사진에 익숙한 사용자에게도 은염사진과 유사한 특성을 보이도록 화상의 개선과 화질의 보정 등이 요구된다. 본 논문은 은염사진의 계조 특성을 추출하여 전자화상시스템에 적용시켜 은염사진의 계조 특성을 지닌 전자화상을 출력하는 방법을 제시한다. 먼저, 은염사진과 전자사진의 화상 생성 공정을 구체적으로 비교하여 그 차이를 기술하고, 사진 계조 변환의 원리와 방법을 제시한다. 다음으로 사진 계조 변환함수를 구하기 위한 각 시스템의 특성화의 실험을 수행한 결과를 보인다. 최종적으로 이론을 바탕으로 한 실험에서는 사진 계조로 변환된 데이터를 디지털 화상시스템으로 출력하여 은염사진의 계조 특성의 비교분석을 수행한다.

• 대한방사선기술학회지:방사선기술과학
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• 제16권1호
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• pp.57-65
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• 1993

Asymetric system have been introduced in these years by KODAK company nam of Insight system for the purpose of improve the chest image. We have had a problem of chest radiology that it is very difficult to visualize the lung field and modiastinal region at one shot. That's why we are the RT using the technique of high voltage hard quality radiography in chest radiography. Also it is known the c-type wide latitude film can lift up the density of mediastinal structures. Authors investigated the photographic characteristics and physical structure of Insight system. Method 1. Investigated the structure of Emulsion layer. Calculated the particle size of Insight system using SEM(Scanning Electron Microscope). 2. Photographic characteristics has been compared the Insight system with the ortho KM/MG combination in $60{\sim}120kV$ range. Results 1. The particle size of backside film were investigated about 2 times larger that of front side film. 2. The front and backscreen's thickness ratio was detected 1 : 3.87, that the backscreen's thickness was thicker than frontscreen. 3. At the view point of photographic characteristics the frontside of insight system make up the contrast, backside make up the density at low exposure lesion.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.172-173
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• 2007

As the power density and switching frequency increase, thermal analysis of power electronics system becomes imperative. The thermal analysis provides valuable information on the semiconductor rating, long-term reliability. In this paper, thermal distribution of the Non Punchthrough(NPT) Insulated Gate Bipolar Transistor has been studied. For analysis of thermal distribution, we obtained experimental and simulation results by using finite element simulator, Ansys and by using photographic infrared thermometer, we compared experimental date with simulation result. and got good agreement. Also this paper provided thermal distribution of IGBT connected to heat sinks. and this results will be good information to design optimal heat sink for IGBT.

• 대한방사선기술학회지:방사선기술과학
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• 제3권1호
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• pp.49-55
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• 1980

To know the effect of tube voltage to X-ray film image, authors made an experimental study on the exponential value of applied voltage and the effect of scattered ray in photographic contrast, and obtained the results as follows: 1. The exponential value of tube voltage was under the control of the applied voltage, the kinds of screens and grids, and its existence. The range of its value was from 1.03 to 5.3. 2. The efficiency of X-ray production was directly proportional to the applied voltage, and to oftain the same density, the tube current(mAs) was inversely proportional to applied voltage 3. The production of scattered rays was in proportion to the tube voltage, and the photographic contrast was mainly influenced by the scattered rays.