• 반도체디스플레이기술학회지
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• 제16권4호
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• pp.36-40
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• 2017

With an attempt to enhance the visibility of laser beam, we have investigated a black matrix with scattering particles by ray tracing simulations. As the scattering particle density is increased, the detected power by the receiver is increased, thereby enhancing the visibility. In reality, the visibility is reduced with increasing incident angle (away from the normal incidence) of laser beam, a phenomenon also observed by ray tracing simulations. It is due to the fact that the mean path is increased within a highly absorptive BM layer or a smaller number of rays hit the BM area when the incident angle is high. Embedding a number of scattering particles into BM may bring in crosstalk among pixels. However, it is negligible because scattered rays inside highly absorptive BM are re-scattered due to the high scattering particle density, decreasing the power of scattered rays into the active areas.

• Nuclear Engineering and Technology
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• 제4권3호
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• pp.223-228
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• 1972

Radiography에 있어서 피사체로부터의 산란 ${\gamma}$선은 film상의 상질을 나쁘게 하는 큰 요소중에 하나이다. 피사체로부터의 산란선량을 조사하기 위하여 여러가지 폭의 slit에 의한 조사장에서의 film의 흑화농도를 구했다. 또 그때의 투과측정기 검출감도의 양부도 검토했다. 피사체가 두꺼워지면 산란선량이 증가하여 결함검출도가 저하하지만, slit폭을 좁힘으로써 개선할 수가 있었다. 그러고 선원은 $_{60}$Co을 사용했고 시료는 철로서 실험을 했다.

• 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.

• 대한방사선기술학회지:방사선기술과학
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• 제6권1호
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• pp.81-84
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• 1983

Scattered-rays are produced from objects in x-ray diagnosis and the quality of x-ray image is influenced by presence of the scattered-ray. Therefore, constant ways and means to suppress and to eliminate the scattered-ray were devised. Authors made an experimental study on the scattered-ray content in transmitted-ray using acryl phantoms and obtained the results as follows: 1. The scattered-ray content in transmitted-ray is not influenced by filtration and tube voltage. 2. Irradiated field size and the thickness of object are a potent influence to scattered-ray content.

• 한국방사선학회논문지
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• 제12권5호
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• pp.549-555
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• 2018

방사선 영상 기술은 피사체의 조성 및 두께에 따라 변화되는 X선의 흡수계수 차이를 기반으로 형성되는 대조도를 영상화하는 기술로서 영상 검출기에 입사하는 1차선 뿐 만 아니라 산란선이 영상 품질에 큰 영향을 미친다. 이에 본 연구에서는 피사체 두께, 조사야 변화에 따라 발생하는 산란선이 영상 품질에 미치는 영향을 고찰하고자 몬테카를로 시뮬레이션을 통하여 FSR 및 SPR 분석을 수행하였다. 연구 결과, 피사체 두께에 따른 FSR은 최대 15.3%p, SPR은 2.00 ~ 4.54로 분석되었으나, 조사야 변화에 대해서는 일정한 값을 유지하는 것으로 분석되었다. 이러한 결과를 바탕으로 피사체 두께는 영상 품질에 영향을 미치는 인자로서 고려되어야 하지만, 조사야는 영상 품질에 영향을 미치지 못하는 인자임을 검증하였다. 이러한 본 연구 결과는 영상 품질 개선을 위한 산란선에 대한 기초 자료로서 활용할 수 있을 것으로 사료된다.

• 대한방사선기술학회지:방사선기술과학
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• 제24권1호
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• pp.23-26
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• 2001

The spatial distribution of the scattered dose for mobile X-ray radiography is measured. The scattered X-ray exposures at the radius of 50, 100 and 150 cm from the irradiation center are 880, 180 and $50\;{\mu}R$, respectively. This scattered X-rays can be reduced to 60% by inserting the portable shield made by 0.4 mm copper sheet sandwiched in two plywoods.

• 한국방사선학회논문지
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• 제17권1호
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• pp.63-69
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• 2023

두·경부 방사선치료에서 환자자세 고정과 재현성을 위하여 사용하는 열가소성플라스틱 마스크는 피부와 밀착되어 산란선을 유발한다. 고정용구 마스크에서 발생되는 산란선으로 인한 피부선량의 증가를 확인하기 위하여 고정용구의 피부밀착 부위를 감소시킴에 따른 산란선의 감소를 CT 스캔한 이미지를 이용하여 전산화치료계획 시스템을 통해 확인하였다. 또한 고정용구의 커버 부위 감소에 따른 셋업의 재현성문제를 확인하기 위하여 DRR과 CT영상을 이용하여 셋업의 차이를 확인하였다. 고정용구로 커버하는 부위를 감소시킴에 따라 피부표면의 선량은 유의하게 감소하였으며 얼굴 전체를 커버하여 고정하지 않아도 재현성에 재현성에 큰 차이가 없음을 확인하였다.

• 대한방사선기술학회지:방사선기술과학
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• 제7권1호
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• pp.41-46
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• 1984

Authors investigated an influence of x-ray tube voltage on x-ray quality and dose with using objects of various thickness, and obtained the results as follows: 1. Radiographic effects were influenced by tube voltages and objects. 2. Dose decrement rates hade more influence upon primary-rays than total x-rays at lower tube voltages. 3. The quality of transmitted x-rays was affected by tube voltages and thickness of objects. 4. Scattered-ray contents were proportional to tube voltages with using grid.

• Animal Systematics, Evolution and Diversity
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• 제28권4호
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• pp.304-307
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• 2012

A three specimen of Icelus toyamensis, belonging to Cottidae, Scorpaeniformes, was firstly collected from the East Sea, Korea during 2007-2009. We herein described the species as the first record from Korea on the basis of these specimens. Icelus toyamensis is characterized by the following morphological combinations: spinous scales absent on the base of dorsal fin; small ctenoid scales scattered on body sides; gill rakers are short, tubular, and relatively broad; the uppermost preopercular spine is sharp and simple; dorsal fin rays VIII-IX, 20-21; anal fin soft rays 18-19; pectoral fin rays 18, and vertebrae 40-41. New Korean name of I. toyamensis is proposed as "Min-jul-ga-si-hoet-dae."

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 1999년도 Japanese Journal of Medical Physics
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• pp.278-281
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• 1999

The purpose of this study is to investigate the effect of the scattered x-rays on the subject contrast and image sharpness for various tube voltages. For the purpose, we measured the scatter-to-primary ratio(SPR) for the tube voltages f 50 to 100kV and obtained the tube voltage dependence of the subject contrast of an aluminum plate in a polymethyl methacrylate(PMMA) phantom. Furthermore, the overall modulation transfer functions(MTFs), which consist of MTFs of a screen-film system and scatter FTMs, were obtained for tube voltages of 50 to 100 kV. The subject contrast decreased with the tube voltage due to that the SPR increased with the tube voltage and that the difference in effective linear attenuation coefficients between the object and its surroundings decreased with the tube voltage. The maximum frequency of the overall MTF decreased from about 2 mm$\^$-1/ to 1 mm$\^$-1/ with the tube voltage increasing from 50 to 100 kV.