• 제목/요약/키워드: Blue screen

검색결과 80건 처리시간 0.021초

증감지와 필름에 따른 방사선상 변화에 대한 연구 (THE COMPARATIVE EVALUATION OF FILM-SCREEN COMBINATIONS)

  • 최경자;최승규
    • 치과방사선
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    • 제18권1호
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    • pp.213-225
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    • 1988
  • This study was to compare the quality of image by different screen and film combinations. Using the sensitometer measured the speed and average gradient of blue sensitive films and orthochromatic films. The films was combined with rare earth screen LR, LM, LF and conventional screen OM, OH, XOR, OKa and exposed the step wedge to impulse 2, 3, 4, 6, 10, 15, 24,3 8, 60 and measured the density. The following results were obtained: 1. The density of film and film-screen combinations showed significant difference, then in film-screen combinations was significantly different by the screens than films. 2. The speed of blue sensitive films was little different, the TMG of orthochromatic films produced high speed, and the AX film was high average gradient. 3. The relative speed of film-screen combinations showed significant difference, and was high in the OKa of the conventional screens and in the LR of the rare earth screens, especially that of LR screen in the combination with blue sensitive films was high. 4. The average gradient of film-screen combinations showed no significant difference, and was high in the OKa screen and LR/OG combination, and that of OKa/AX combination was highest. 5. The latitude of film-screen combinations showed significant difference by screens, and was high in the LM screen in combination with blue sensitive films and in the OM screen in combination with orthochromatic films. 6. The subject contrast of film-screen combinations showed significant difference by screen, and was high in the LR screen in combination with blue sensitive AX film and orthochromatic TMG film.

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신구법천문도 채색 안료 비교 및 제작시기 추정 (Comparison of Pigments and Estimation of Production Period in Old and New Celestial Charts Folding Screens)

  • 오준석;황민영;야마토 아스카;아라이 케이;이새롬
    • 보존과학회지
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    • 제36권5호
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    • pp.351-367
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    • 2020
  • 신구법천문도 3점(국립민속박물관 소장 『천문도(병)』, 『신구법천문도 8폭 병풍』, 일본 국회도서관 소장 『황도남북양총성도』)에 대한 채색 안료 분석 및 이를 통한 제작시기를 추정하였다. 『천문도(병)』에서는 조선에서 널리 사용되어오던 석청(남동광), 청화(쪽), 석록(공작석), 하엽(아타카마이트), 주, 석간주(산화철), 연지(코치닐), 등황, 석자황, 연분, 활석 등과 같은 전통적인 유·무기질 안료들이 사용되었다. 『신구법천문도 8폭 병풍』와 『황도남북양총성도』에서는 19세기 중엽 이후 유럽에서 유입된 합성 무기안료인 양록(에메랄드 그린)과 양청(울트라마린 블루)가 사용되었다. 『신구법천문도 8폭 병풍』에서는 녹색과 청색에 합성 무기안료만 사용되었지만, 『황도남북양총성도』에서는 전통적으로 사용되어온 하엽과 청화도 함께 사용되었다. 신구법천문도의 성도와 도설 연구와 연계하여 안료 분석결과로부터 추정한 제작시기는, 조선시대 전통안료만으로 채색된 『천문도(병)』 18세기 중엽 이후로 추정되며, 『황도남북양총성도』와 『신구법천문도 8폭 병풍』은 19세기 중엽 서양의 녹색과 청색 안료가 도입된 후 제작되었다. 그리고 전통안료와 서양의 합성안료가 함께 사용된 『황도남북양총성도』가 『신구법천문도 8폭 병풍』 보다 제작시기가 빠른 것으로 추정된다.

$CaWO_4$$Gd_2O_2S$ : Tb 증감지의 형광체 형태와 사진감도 특성에 관한 연구 (A Study on the Photographic Characteristics Related to the Morphology of Phosphor Layers in the $CaWO_4$ and $Gd_2O_2S$ : Tb Screen)

  • 이인자;허준
    • 대한방사선기술학회지:방사선기술과학
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    • 제16권1호
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    • pp.41-55
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    • 1993
  • Recently, various screen film system have been introduced in diagnostic radiology. There are two kinds of screen film system : blue emitting $CaWO_4$ screen has been largely used in these days. However, it tends to be changed to use green emitting $Gd_2O_2S$ : Tb screen. In this study, photographic characteristics of $CaWO_4$ and $Gd_2O_2S$ : Tb screen were investigated with luminescence, spectroscopy. The morphology of $CaWO_4$ and $Gd_2O_2S$ : Tb were also observed by using scanning electron microscope. The result obtained were as follows : 1. There was small difference in the thickness of phosphor layers for the front and back screen of blue emitting system, but little difference in those of green emitting system. 2. There was no difference in the size of phosphor particles between the front and back screen for each screen. However, the particle size was different for the various kinds of screens. 3. The shape of phosphor particle was round with many faces for all the screens. 4. In the exposure of X-ray with the same intensity, luminescent intensity of a green emitting system was $6{\sim}7$ times larger than that of a blue emitting system. 5. The thickness of phosphor layers does not affect on the sensitivity of the screens exposed by X-ray.

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증감지의 발광스펙트럼에 따른 특성곡선의 변화 (Change of Characteristic Curves using Light Emission Spectrum of the Intensifying Screens)

  • 윤철호;강홍석;이인자;허준
    • 대한방사선기술학회지:방사선기술과학
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    • 제13권2호
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    • pp.21-25
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    • 1990
  • This report is study about difference of H-D curve in regular film and ortho type film, and obtained results as follows : 1. In the blue-color emission intensifying screen, ortho type films and in the green-color emission intensifying screens, regular type are decreased in their gradient. 2. When joint use of regular type film and ortho type film, the gradient difference not seen in blue color screen. 3. The gradient difference seen clearly in G4, KM screens(green color emission intensifying). Especially, in part of high film density, the gradient difference are great. So we have to right use of screen and film because not matched used of theare the sensitivity and gradient are decrease.

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가상 스튜디오를 위한 카메라 파라메터의 추출 (The Extraction of Camera Parameters using Projective Invariance for Virtual Studio)

  • 한서원;엄경배;이준환
    • 한국정보처리학회논문지
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    • 제6권9호
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    • pp.2540-2547
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    • 1999
  • 크로마키 합성이란 텔레비전 방송국 또는 일반 스튜디오에서 사용되는 영상처리 기술로써, 블루스크린을 배경으로 하는 스튜디오에서 촬영된 영상의 파란부분을 컴퓨터 그래픽 또는 실영상으로 교체하여 합성하는 기술이다. 특히, 가상 스튜디오의 크로마키 합성은 배경영상을 카메라의 움직임에 연동하여 변화시킴으로써 기존 스튜디오보다 자연스러운 합성을 수행할 수 있다. 본 논문에서는 카메라의 움직임에 연동하여 블루스크린에 그려진 오각형패턴의 변화만을 인식하여 역으로 카메라 파라메터를 추출하는 방법을 제안하였다. 일반적으로 오각형패턴은 카메라의 움직임 즉 투영변환에 불변하는 특징을 가지고 있으므로 이를 이용하여 스크린 위의 오각형패턴과 촬영된 영상 위의 대응패턴을 용이하게 구할 수 있다. 그리고, 구해진 대응패턴과 대응점을 이용하여 평면의 투영 변환식을 구하고 이를 변형된 Tsai의 방법을 사용하여 카메라 파라메터를 추출한다. 실험 결과를 통하여 제안된 방법이 원래의 Tsai의 방법보다 정확한 카메라 파라메터를 구할 수 있었으며 Pentium-MMX PC에서 초당 12 프레임의 카메라 파라메터를 추출할 수 있었다.

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증감지(增感紙)-필름계(系)의 상대감도(相對感度)와 절대감도(絶對感度)에 관한 실험(實驗) (The Relative and Absolute Speed of Radiographic Screen-Film Systems)

  • 허준;이인자
    • 대한방사선기술학회지:방사선기술과학
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    • 제16권1호
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    • pp.67-80
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    • 1993
  • Recently, a large number of new screen-film systems have become available for use in diagnostic radiology. These new screens are made of materials generally known as rare-earth phosphors which have high x-ray absorption and high x-ray to light conversion efficiency compared to calcium tungstate phosphors. The major advantage of these new systesms is reduction of patient exposure due to their high speed or high sensitivity. However, a system with excessively high speed can result in a significant degradation of radiographic image quality. Therefore, th speed is important parameters for users of these system. Our aim of in this was to determine accurately and precisely the absolute speed and relative speeds of both new and conventional screen-film system. We determined the absolute speed in condition of BRH phantom beam qulity and the relative speed were measured by a split-screen technique in condition of BRH and ANSI phantom beam qulity. The absolute and the relative speed were determined for 8 kinds of screen-4 kinds of film in regular system and 7 kinds of screen-7 kinds of film in ortho system. In this study we could know the New Rx, T-MAT G has the highest film speed, also know Green system's stndard deviation of relative speed larger than blue system. It was realized that there were no relationship between the absolute speed and the blue system. It was realized that there were no relationship between the absolute speed and the relative speed in ortho or regular system.

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시각 특성을 기반한 청색잡음 스크린 제작 (Blue Noise Screen Design Based on Human Visual Chracteristics)

  • 박희윤
    • 한국인쇄학회지
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    • 제16권2호
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    • pp.75-89
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    • 1998
  • FM screening has been praised for its apparent resolution advantage over conventional AM screening. FM screening is also known for its criticalness of film output and difficulties in the proofing stage because of the microdot formation. However, FM screening is not a well understood process from press performance point of view. This study was carried out for the purposes of introducing the availability of hifi-offset printing to domestic printing industries and evaluating the print qualities between 300lpi AM screen and FM screen with the equivalent sized microdots to 4-5% dot area of the 300lpi AM screen, together with comparing with 175lpi AM screen representing a conventional printing. Solid density, dot gain, color gamut and some other quality properties were measured and discussed.

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Electroanalytical Applications Based on Carbon Nanotube/Prussian Blue Screen-printable Composite

  • Shim, Jun-Ho;Lee, Jae-Seon;Cha, Geun-Sig;Nam, Hak-Hyun
    • Bulletin of the Korean Chemical Society
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    • 제31권6호
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    • pp.1583-1588
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    • 2010
  • A single step fabrication process of carbon nanotube/Prussian Blue (CNT/PB) paste electrodes based on screen printing technology has been studied as an amperometric sensor for the determination of hydrogen peroxide and free chlorine. Compared to the classical carbon paste (CP) electrode, the CNT paste electrode greatly enhanced the response in the presence of hydrogen peroxide due to the electrocatalytic activity of the CNT. Based on the CNT/binder paste, PB was also incorporated into a network of CNT paste and characterized. The best electroanalytical properties of PB-mixed sensors to hydrogen peroxide were obtained with PB ratio of 10 wt % composition, which showed fast response time ($t_{90}{\leq}5$ s; 0.2 - 0.3 mM), low detection limit of 1.0 ${\mu}M$, good linear response in the range from $5.0{\times}10^{-5}$ - $1.0{\times}10^{-3}$ mol $L^{-1}$ ($r^2$ = 0.9998), and high sensitivity of -8.21 ${\mu}AmM^{-1}$. In order to confirm the enhanced electrochemical properties of CNT/PB electrode, the sensor was further applied for the determination of chlorine in water, which exhibited a linear response behavior in the range of 50 - 2000 ppb for chlorine with a slope of 1.10 ${\mu}Appm^{-1}$ ($r^2$ = 9971).

The Study of Mutation Spectrum in Iac / Gene of Transgenic Big Blue$\textregistered$ Cell Line Following Short-Term Exposure to 4-Nitroquinoline N-oxide

  • Youn, Ji-Youn;Kim, Kyung-Ran;Cho, Kyung-Hea;Ryu, Jae-Chun
    • 한국환경독성학회:학술대회논문집
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    • 한국환경독성학회 1996년도 제19회정기학술대회(The 19th Symposium of the Korean Society of Environmental Toxicology)
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    • pp.64-64
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    • 1996
  • Transgenic animal and cell line models which are recently developed in toxicology field combined with molecular biological technique, are powerful tools for studying of mutation in vivo and in vitro, respectively. The Big Blue mutagenesis assay system is one of the most widely used transgenic systems. Especially, for the study of direct acting mutagens, Big Blue cell line is very useful and powerful to evaluate mutagenicity because the mutation frequency and mutationspectrlun showed no distinct differences between cell line and animal. The Big Blue cell lines carry stably integrated copies of lambda shuttle vector containing lac I gene as a mutational target. These lambda shuttle vectors are useful for various mutagenesis related studies in eukaryotic system due to their ability to be exposed mutagen and then transfer a suitable target DNA sequence to it convenient organism for analysis. We tried to assess the mutagenic effect of 4-NQO with Big Blue cell line. After the treatment of 4-NQO, genomic DNA was isolated and lambda shuttle vector was packaged by in Vitro packaging and then these were plated on bacterial host in the presence of X-gal to screen mutation in the lac I. We determined MF as a ratio of blue plaques versus colorless plaques and now undergoing the mutation spectrum of 4-NQO in lac J gene sequence.

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LCD 컬러필터용 밀베이스의 분산 연구 (A Study on the Millbase Dispersion for LCD Color Filters)

  • 정일봉;안석출;남수용
    • 청정기술
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    • 제14권1호
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    • pp.21-28
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    • 2008
  • 본 연구에서는 LCD 컬러필터에 사용되는 밀베이스를 제조하기 위해 Red, Green, Blue 안료 분산에 대한 특성을 연구하였다. 또한 기존의 포토리소그라피 방법을 대체할 수 있는 스크린 인쇄 방식에 적용할 수 있도록 물성 및 점도를 맞추었다. 분산제는 BYK-2000, 모노머는 EB-140이 가장 우수한 분산 특성을 나타내었다. Torus mill을 사용하여 millbase를 500 rpm으로 30 min 동안 pre-mixing한 뒤, 4000 rpm으로 $5{\sim}6$시간 분산시켜서 Red $100{\sim}110\;nm$, Green $50{\sim}70\;nm$, Blue $60{\sim}80\;nm$의 분산 결과를 얻을 수 있었다. 저점도 type 포물레이션에서 millbase의 점도가 $200{\sim}300\;cps$ 일 때 비드의 충격력이 충분히 발휘되었으며, 레오로지 거동 및 색특성을 통하여 분산성이 확보되었음을 확인하였다.

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