• 치위생과학회지
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• 제5권4호
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• pp.221-225
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• 2005

구강진료기관에서의 개인방호의 중요성을 일깨우기 위해 보건대학 치위생과 3학년 재학생을 대상으로 치면세마와 엑스선 촬영 실습 수행과정에서 감염관리 및 엑스선안전관리에 대한 실천 정도를 조사하여 아래와 같은 결과를 얻었다. 1. 치면세마 실습시에는 감염관리에 대해 높은 수준으로 인식하고 철저히 수행하고 있었다. 2. 엑스선촬영 실습시에 감염관리의 필요성에 대한 인식 정도는 비교적 낮았다. 3. 엑스선촬영 실습시에는 필름유지기구를 제외하고는 거의 감염관리를 하지 않고 있었다. 4. 엑스선촬영 실습시에 엑스선안전관리에 대해서는 높은 수준으로 인식하고 실천하고 있었다. 이상의 결과를 종합해 볼 때 엑스선촬영시에는 거의 감염관리가 이루어지지 않고 있다는 것을 알 수 있다. 완벽한 감염관리를 위해 엑스선촬영시에도 철저한 감염관리가 이루어질 수 있도록 필요성에 대한 인식제고와 실천율을 높일 수 있는 교육의 강화가 요구된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.392-395
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• 2003

For the purpose of digital x-ray imaging, many materials such as $PbI_2$, $HgI_2$, TlBr, CdTe and CdZnTe have been under development for servaral years as direct converter layer. $Hgl_2$ film detector have recently been shown as one of the most promising semiconductor materials to be used as direct converters in x-ray digital radiography. This paper, the $HgI_2$ films are deposited on conductive-coated glass by screen printing, in which $HgI_2$ powder is embedded in a binder and solvent, and the slurry is used to coat the conductive-coated glass. We investigated electrical characteristic of the fabricated $HgI_2$ films. The x-ray response to radiological x-ray generator of 70Kvp using the current integration mode will be reported for screen printing films. These results indicate that $HgI_2$ detectors have high potential as new digital x-ray imaging devices for radiography.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1998년도 추계학술대회
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• pp.94-95
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• 1998

We developed a digital x-ray medical imaging system using commercially available amorphous silicon image sensor plate. The image readout could be accomplished within 3.5 sec after radiation exposure and be displayed on a monitor through computer interface. This system needs not the conventional x-ray films and film processors, and also provides digital radiographic images. This system is the fastest digital radiography system developed so far, and expected to replace many of the conventional x-ray film systems or digital radiography systems.

• International Journal of Precision Engineering and Manufacturing
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• 제9권4호
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• pp.86-100
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• 2008

This article reviews the development of flat-panel detectors for digital radiography based on amorphous materials, Important design parameters and developments are described for the two main components of flat-panel detectors: the X-ray converter and the readout pixel array. This article also introduces the advanced development concepts of new detectors. In addition, the cascaded linear systems method is reviewed because it is a very powerful tool for improving the design and assessment of X-ray imaging detector systems.

• 대한방사선기술학회지:방사선기술과학
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• 제3권1호
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• pp.43-48
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• 1980

An experimental study was carried out to make a comparison between tube voltage and density of barium sulphate in the stomach radiography. The results were summarized as follows: 1. The percentage of density on concentrations of barium sulphate as contrast media could not show in differences with changes of voltages applied X-ray tube. 2. The changes of density visualized on X-ray film mainly depend upon with thickness of stomach filled barium sulphate than the ratio of barium sulphite and plain water volume. 3. The lesions positioned in upper part within stomach exhibited their best discrimination performanance with depth in the low tube voltage, followed in order by the middle part and lower part. However, the discrimination performanance at the high tension radiography uniformly visualized over X-ray film without density in change.

• 한국방사선학회논문지
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• 제12권5호
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• pp.651-658
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• 2018

방사선사는 일반촬영 시에 다양한 환자를 만나게 된다. 노령환자, 유아 등 몸이 불편한 환자를 검사하게 된다. 소규모의 병 의원에는 방사선사가 혼자 업무를 보는 경우가 자주 발생한다. 이러한 경우 방사선사의 두 손은 환자의 자세를 유지하는데 사용되어지기 때문에 촬영에 있어서 어려움을 느끼게 된다. 본 연구는 이러한 문제점을 극복하고자 진단용 방사선 발생 발판 스위치를 고안하여 실험하였다. 제작한 발판 스위치를 진단용 엑스선 촬영장치에 장착하여 조사선량 재현성 시험, kVp, mAs, 백분율평균오차와 같은 정량적 평가를 실시하였다. 결과적으로 발판 스위치 사용에 대한 정량적 평가는 조사선량 재현성 시험에서 변동계수가 0.05이하로 측정되었고 kVp 시험에서는 백분율 평균오차가 ${\pm}10%$ 이내로 측정되었다. mAs 시험에서도 백분율 평균오차가 ${\pm}20%$ 이내로 측정되었다. 이는 진단용 방사선 발생장치의 검사기준 범위에 모두 부합하여 사용상 문제점은 제시되지 않았다. 또한 현재 근무 중인 방사선사를 상대로 유용성에 관한 정성적 평가를 실시하였다. 결론적으로 발판스위치의 엑스선 발생효율의 정량적 평가에서는 실험된 검사가 엑스선 발생장치 장비 기준 범위에 부합하였으며 설문을 통한 평가에서도 먼저 병 의원에서 근무하는 방사선사를 상대로 발판 스위치를 사용한 이후 설문을 통해 발판 스위치에 대한 편리성과 활용성에 대해 설문 실시한 결과는 발판스위치 사용은 임상에서 많은 도움을 줄 수 있는 긍정적인 결과로 나타내었다. 그러므로 진단용 엑스선 촬영용 발판 스위치를 사용하면 방사선 기술자 작업의 신속성과 정확성을 효과적으로 향상시킬 수 있으므로 의료 서비스 만족도를 높이는 데 효과적으로 사용할 수 있을 것이다.

• Imaging Science in Dentistry
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• 제48권3호
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• pp.167-176
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• 2018

Purpose: In the age of X-ray computed tomography (CT) and digital volume tomography (DVT), with their outstanding post-processing capabilities, indications for planar radiography for the study of the dentition of ancient Egyptian mummies may easily be overlooked. In this article, the advantages and limitations of different approaches and projections are discussed for planar oral and maxillofacial radiography using portable digital X-ray equipment during archaeological excavations. Furthermore, recommendations are provided regarding projections and sample positioning in this context. Materials and Methods: A total of 55 specimens, including 19 skeletonized mandibles, 14 skeletonized skulls, 18 separate mummified heads, and 4 partially preserved mummies were imaged using portable digital X-ray equipment in the course of archaeological excavations led by the University of Basel in the Valley of the Kings between 2009 and 2012. Images were evaluated by 2 authors with regard to the visibility of diagnostically relevant dental structures using a 4-point grading system(Likert scale). Results: Overall, the visibility of diagnostically relevant dental structures was rated highest by both authors on X-ray images acquired using a dental detector. The tube-shift technique in the lateral projections of mandibular dentition achieved the second-best rating, and lateral projections achieved the third-best rating. Conclusion: Conventional planar digital X-ray imaging, due to its ubiquity, remains an excellent method-and often the only practicable one-for examining the skulls and teeth of ancient Egyptian mummies under field conditions. Radiographic images of excellent diagnostic quality can be obtained, if an appropriate methodology regarding the selected projections and sample placement is followed.

• 대한방사선기술학회지:방사선기술과학
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• 제8권2호
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• pp.15-19
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• 1985

The seattered-ray have a bad effect to the image of x-ray film. Therefore, to obtain the better x-ray image, the most important point is to eliminate the scattered-ray, come from the patient, and the easiest method to eliminate the scattered-ray is to use a proper grid for tube voltages. Authors made an experiment on the scattered-ray contents and the image quality in skull radiography, and obtained the results as follows; 1. The scattered-ray content in skull radiography was 83%, but it could be reduced to 35%-50% by using grid. 2. The image contrast was most increased when the using grid ratio was 8:1. 3. The image quality was not influenced by the scattered-ray contents between 32% and 45%.

• 대한디지털의료영상학회논문지
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• 제10권2호
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• pp.23-31
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• 2008

Computed radiography(CR) has been widely used in the field of diagnostic radiography since digital X-ray image was introduced. The imaging performance of CR system was studied by analyzing the digital image data of the CR images which are the outcomes of the whole imaging system composed of image plate(IP), laser digitizer, analoge-digital convertor, and a given image processing unit. In this study, we used a conventional CR system made by Agfa. From the flat field image of 150$\times$150 image pixels, signal-to-noise ratio(SNR) was calculated. SNR of the CR image increases in proportion to logarithm value of the X-ray exposure irradiated on the IP. SNR is less than about 6 at the exposure below 0.2mR and is more than 10 at the exposure above 0.54mR. In our study, most of images obtained by the smaller exposures less than 2.0mR can not be readable. In general, the minimum value of the SNR ranges from 3 to 5. We obtained modulation transfer function(MTF) by analyzing the bar pattern image which was made under conditions as follows: X-ray tube potential was 55kVp, the IP exposure was 0.54 mR, and the distance between X-ray source to IP was 2m, where bar pattern was located on the IP. MTF is 23% at 2.5lp/mm spatial frequency. Provided that the MTF of noise equivalent modulation is 10%, the CR system has the limiting spatial resolution of 3.2lp/mm. If the image sharpness is evaluated by the spatial frequency where MTF is 50%. the corresponding spatial frequency is 0.5$\sim$0.75lp/mm. MTFA(Modulation Transfer Function Area) is 1.0lp/mm. Compared with the Fuji CR whose MTFA is 1.1lp/mm, Agfa CR in this study shows almost same MTFA performance.

• 한국방사선학회논문지
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• 제4권3호
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• pp.5-11
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• 2010

본 논문에서는 이중 에너지 디지털 래디오그래피를 위한 이중 모드 검출기 개발을 제안한다. 이중 에너지 래디오그래피 모듈의 설계를 위하여 상용 BIS(Baggage Inspection System)에서 사용되고 있는 X-선 발생장치의 스펙트럼과 이중 모드 검출기에 대한 특징 및 방사선적 특성을 분석하였다. 제안하는 영상 검출기 모듈은 BIS에서 활용되고 있는 X-선관을 대상으로 X-선 스펙트럼을 모사하고, 모사한 스펙트럼을 통하여 새롭게 제안하는 검출기 모듈의 방사선적 특성을 고찰하였다. X-ray를 이용한 실험에서 구리 필터의 두께 증가에 따라 저에너지 검출기(LED)와 고에너지 검출기(HED)의 출력신호의 차이는 같이 증가하였다. 특히 HED에서의 출력신호의 크기는 구리 필터 두께가 증가 할수록 감소함을 알 수 있었다.