• 대한방사선기술학회지:방사선기술과학
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• 제24권2호
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• pp.5-11
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• 2001

Most of X-ray generator had used rectifier type transformer with high tension generator which is supplied in a clinical diagnosis. Because the ripple rate of tube voltage is high, X-ray generating efficiency is very low. In these days, high tension generator for inverter type X-ray generator is being supplied from a broad which uses semi-conductor switching element for the electric power that have a high speed switching ability to solve these problem. But, semi-conductor element with large capacity is used with X-ray tube's large consumption power and diffusion is difficult in the small size hospital because production cost is going up by doing digital control through DSP. Therefore, this paper designed and manufactured CR type voltage divider for feedback control of tube voltage with high frequency resonance type inverter and for high tension transformer with high frequency. It was to make economical diffusion type X-ray generator which has wide output voltage and load extent. It was preyed that the X-ray generator had the stability of X-ray tube's output characteristics.

• 한국방사선학회논문지
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• 제10권3호
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• pp.201-206
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• 2016

유방암에 관한 사회적인 관심이 증가되고 있는 가운데 진단의 가장 기본이 되는 검사는 유방 X선 촬영과 유방 초음파 검사이다. 특히 유방 미세석회화는 조직학적 진단을 필요로 하며 유방 미세석회화 조직검사를 시행하고 있다. 이에 미세석회화 진단에 기본이 되는 X선 유도 하 조직검사(needle localized open biopsy)와 초음파 유도 하 조직검사(sono guided core needle biopsy)를 분석하여 평가하고자 한다. 유방 미세석회화를 주소로 내원한 환자에서 확대 촬영을 시행한 241예를 대상으로 X선 유도 하 조직검사(needle localized open biopsy)와 초음파 유도 하 조직검사(sono guided core needle biopsy)의 연령대 별 분포와 병소의 위치를 분석하고 확대촬영 시행 후 이루어진 검사를 분류해서 X선 유도 하 조직검사와 초음파 유도 하 조직검사의 빈도를 분석하고 악성과 양성의 결과를 확인 하였다. 그 결과 X선 유도 하 조직검사(needle localized open biopsy)가 64예(26.6%)로 초음파 유도 하 조직검사(sono guided core needle biopsy) 12예(4.9%)에 비해 5.4배 높은 것으로 나타났다. 초음파 장비의 발달과 입체정위 흡입법(stereotactic vacuum-assisted biopsy)등의 발달로 미세석회화의 조직학적 진단방법이 다양해지고 있지만, 각각 검사의 특성과 한계점을 고려해 볼 때 X선 유도 하 조직검사(needle localized open biopsy)가 유방 미세석회화 병변에서는 정확한 조직학적 진단을 제공한다고 사료된다.

• 한국전기전자재료학회논문지
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• 제24권1호
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• pp.36-41
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• 2011

Medical X-ray has been brought many changes according to the rapid development of high technology. Especially, for high-voltage generator which is the most important in X-ray generation the traditional way is to use high-voltage electric transformers primarily. However, since it is large and heavy and the ripple rate of DC high-voltage applied to X-ray tube is too big, it has a disadvantage of low X-ray production efficiency. To solve these problems, the studies about high-voltage power supply are now proceeding. At present, the high-voltage generator that generates high-voltage by making high frequency using inverter control circuit consisting of semiconductor device is mainly used. High-voltage generator using inverter has advantages in the diagnosis using X-ray including high performance with short-term use, miniaturization of power supply and ripple reduction. In this study, the X-ray high-voltage device with inverter type using pulse width modulation scheme to the control of tube voltage and tube current was designed and produced. For performance evaluation of produced device, the control signal analysis, irradiation dose change and beam quality depending on the load variation of tube voltage and tube current were evaluated.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1528-1535
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• 1997

Many radiological modalities has been applied to medicine as a basic fundamental diagnosis and therapy recently. The prevalence of computer systems affect most images to be digitized. However conventional X-ray film images are not digital images eventhough they covers 70% of all radiologica images. This is the hinderacne of building PACS. In this paper all radiological digital imaging parts such as DSA. CR. MRI. SPECT. PET and ultrasonography were briefly introduced and the applications were described. In brief digital radiography contribute to enhance the medical service quality. And the digital substituition of conventional X-ray film image is inevitable.

• Journal of Radiation Protection and Research
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• 제47권1호
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• pp.39-49
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• 2022

Background: For proper monitoring of the eye lens dose, an appropriate calibration factor of a dosimeter and information about the mean energies of X-rays are indispensable. The scattered X-ray energy spectra should be well characterized in medical practices where eye lenses of medical staffs might be high. Materials and Methods: Scattered X-ray energy spectra were experimentally derived for three different types of X-ray diagnostic and therapeutic equipment, i.e., the computed tomography (CT) scan, the angiography and the fluoroscopy. A commercially available CdZnTe (CZT) spectrometer with a lead collimator was employed for the measurement of scattered X-rays, which was performed in the usual manner. Results and Discussion: From the obtained energy spectra, the mean energies of the scattered X-rays lied between 40 and 60 keV. This also agreed with that obtained by the conventional half value layer method. Conclusion: The scattered X-rays to which medical workers may be exposed in the region around the eyes were characterized by means of spectrometry. The obtained mean energies of the scattered X-rays were found to match the flat region of the dosimeter response.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.3230-3232
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• 2000

DR (Digital Radiography) system will be the best candidate for next generation x-ray diagnosis system. DR system will replace x-ray film by computer monitor and provide various merits like reduced processing time, easy recording, remote diagnosis and etc. In this paper, we propose the pre-processing algorithm which is designed to compensate dead and defected pixel for x-ray detector panel. We also designed DSP(Digital Signal Processor) based DR image processing board for real-time processing of suggested algorithm.

• 순환기질환의공학회:학술대회논문집
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• 순환기질환의공학회 2006년도 제6회 학술대회
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• pp.46-48
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• 2006

• 한방재활의학과학회지
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• 제30권2호
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• pp.125-137
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• 2020

Objectives The purpose of this study was to examine how changes in the cervical spine correlate with body posture changes in the whole body, and to find out the significance of complementary clinical application X-ray and Chuna posture analysis. Methods From January 1, 2019 to October 31, 2019, the results of 27 patients with pain in the vertebral region were analysed in accordance with the results of cervical X-ray and Chuna posture analysis. In order to confirm the significance of Chuna posture analysis results, the survey of 187 Chuna standard curriculum instruction qualification certifiers was conducted and the responses of 47 of them were analyzed. Results The occiput-atlas cline angle increases in both hypolordosis/hyperlordosis groups based on cervical lordosis angle, and increases further than in the hyperlordosis group. There were significant correlations between the changes in the cervical spine and the body posture changes in the whole body. There were no significant differences between cervical X-ray sagittal parameters and the body posture analysis parameters based on the patient's major disease codes. Conclusions As a result of conducting a survey on the clinical importance of the body posture analysis parameters, the importance of cervical parameters was verified. Changes in the cervical spine may not only cause other changes in the cervical region, but also affect the body posture changes in the whole body. The complementary application of X-ray and Chuna posture analysis results is helpful in clinical diagnosis and treatment of musculoskeletal disorders.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제12권6호
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• pp.243-250
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• 2023

흉부 X-ray 영상은 폐와 심장을 검사하는 방사선 검사이며 특히, 폐 질환을 진단하는 데 널리 사용되고 있다. 이러한 흉부 X-ray의 품질은 의사의 진단에 영향을 줄 수 있으므로 품질을 평가하는 과정이 필수적으로 거쳐야 하는데, 이 과정은 영상의학과 전문의의 주관이 개입될 수 있고, 수작업으로 이루어지기 때문에 많은 시간과 비용이 소모된다. 또한, 이러한 품질평가는 X-ray 영상의 특징과 사용 목적에 따라 일반적인 품질평가와는 다른 평가 요소가 필요하다. 따라서 본 논문에서는 X-ray 영상에서 검출되는 장기의 해상도, ,해부학적인 구조, 균형 등을 고려하여 임상 현장에서 사용되는 흉부 X-ray 영상 화질 평가 가이드라인을 적용하여 품질요소를 5가지(인공음영, 포함범위, 환자자세, 흡기정도, 그리고 투과상태)로 나누고 이를 자동화하는 도구를 제안한다. 제안하는 도구는 수작업으로 품질평가를 진행하는 본래의 방식 대비 소요 시간과 비용을 줄여주고, 더 나아가 흉부 X-ray를 이용한 학습 모델 개발에 높은 품질의 학습데이터를 선별하는 과정에도 사용될 수 있다.

• 전자공학회논문지 IE
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• 제46권3호
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• pp.62-67
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• 2009

본 논문에서는 퍼지논리시스템을 이용하여 ROC 곡선을 설계하였다. ROC 곡선은 진단평가를 위하여 이용되고, ROC 곡선을 평가하는 진단자는 초보 진단자를 선정하였다. 학습을 통한 ROC 곡선에 관한 진단능력을 평가하기 위하여 흉부 X-선 사진이 사용되었다. 진단을 위해 잡음과 신호(병변)을 갖는 X-선 필름을 사용하였다. 남성과 여성 간의 진단능력의 차이에 관하여 나타난 결과는 여성보다 남성이 우세한 것으로 나타났으나 그 차이는 작은 것으로 나타났다.