• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 하계학술발표회
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• pp.118-120
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• 2000

Currently, x-ray is mostly used for the diagnosis of dental cavity and osteoporosis. The osteoporosis is broadly defined as a decrease in the amount of bone mass per unit volume of the bone. Clinically the manifestation of low bone mass presents a clinical problem to the general population as an increase in fracture risk and especially in aging population[1]. Although the amount of the irradiated x-ray to the human body for the clinical diagnosis is relatively small, the exposition of the x-ray to the human body should be minimized as much as possible, since the x-ray is an ionizing radiation. To investigate other possible systems replacing X-ray, ultrasonic imaging and MRI(Magneto-Resonance-Imaging) systems were studied. Unfortunately, an effective and safe diagnosis tool for detecting the dental cavity and the osteoporosis is currently lacking. (omitted)

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.209-211
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• 1995

This paper is concerned with High Frequency, High Voltage Generator for X-ray using zero-voltage soft-switching PWM DC-DC high-power converter by Resonant method, which makes the most of the parastic LC parameters of high-voltage transformer link, for diagnostic X-ray power generator. The converter circuit basically utilizes phase-shift pulse width modulated series Resonant full-bridge PWM DC-DC high-power converter operating at a constant frequency;25kHz. The converter output regulation is digitally controlled using DSP (Digital Signal Processor) for obtaining a fast rising time and adjust output voltage within a wide load range.

• 한국방사선학회논문지
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• 제14권6호
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• pp.827-832
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• 2020

영상의학과 진료에 자주 이용되는 X선 장비는 임상에서 가장 보편화되어 있고 가장 많이 사용되는 장비이다. 장비는 지속적인 품질관리를 통해서 환자에게 정확한 정보를 제공해야 한다. 수동으로 계측 할 경우 재현성이 떨어지고 평가결과에 대한 신뢰도에 문제가 있을 수 있다.본 연구에서는 현재 임상에서 사용되고 있는 진단용 X선발생장치의 X선관 초점과 가변 조리개의 중심선속이 얼마나 일치하는지를 자동화된 프로그램을 통해서 계측하고 평가하고자 하였다. 실험결과, 두 개의 평가용 중심점 좌표를 계산하는데 성공하였고 두 점간 거리를 픽셀단위로 계산하여 판정에 적용하였다. 중심선속 일치정도가 정상 각도이내에 존재하는지 비정상 범위인지에 대한 자동판정 값을 제시하였다. 본 연구의 결과는 엑스선장치의 품질관리에 도움을 줄 것으로 판단한다.

• Tuberculosis and Respiratory Diseases
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• 제71권1호
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• pp.30-36
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• 2011

Background: Pneumonia is commonly seen in outpatient clinics. it is widely known as the most common cause of death from infectious disease. Pneumonia has been diagnosed by its typical symptoms, chest X-ray and blood tests. However, both chest X-rays and blood tests have limitations in diagnosis. Thus primary care clinicians usually have been constrained due to a lack of adequate diagnostic tools. Vibration response imaging (VRI) is a newly emerging diagnostic modality, and its procedure is non-invasive, radiation-free, and easy to handle. This study was designed to evaluate the diagnostic usefulness of the VRI test among pneumonia patients and to consider its correlation with other conventional tests such as Chest X-ray, laboratory tests and clinical symptoms. Methods: VRI was performed in 46 patients diagnosed with pneumonia in Konkuk University Medical Center. VRI was assessed in a private and quiet room twice: before and after the treatment. Sensors for VRI were placed on a patient's back at regular intervals; they detected pulmonary vibration energy produced when respiration occurred and presented as specific images. Any modifications either in chest X-ray, C-reactive protein (CRP), white blood cell count (WBC) or body temperature were compared with changes in VRI image during a given time course. Results: VRI, chest X-ray and CRP scores were significantly improved after treatment. Correlation between VRI and other tests was not clearly indicated among all patients. But relatively severe pneumonia patients showed correlations between VRI and chest X-ray, as well as between VRI and CRP. Conclusion: This study demonstrates that VRI can be safely applied to patients with pneumonia.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.438-441
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• 1999

This work characterized in terms of the reduction of exposure dose by use of the heavy elements filter in the diagnostic radiology. They contained heavy elements filter of Ho and X-ray beam harding filters such as Al and Cu. From the results of experimental evaluation, it was founded that in the case of the Ho filter, X-ray property was not changed with variety of kVp. The surface dose and absorption dose was increased in order of Cu, He and Al. The contrast of image showed the higher value in order of Cu, Al and Ho.

• 한국의학물리학회지:의학물리
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• 제8권2호
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• pp.35-43
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• 1997

광자선의 흡수계수교정과 차등 투과력이 관련된 연구에서 X선의 스펙트럼은 중요한 관심사이다. 본 연구에서는 전산화단층영상장치의 80, 120 kVp X선의 실험적 투과선량으로부터 수치해석을 통해 에너지스펙트럼을 구하였다. 투과선량은 직경 30cm, 두께 5mm 내지 92.3 mm의 알루미늄 파이프필터의 중앙에 반도체검출기를 설치하고 10mm 슬릿빔의 투과선량을 측정하였다. 스펙트럼재구성은 텅스텐타켓의 특성 X선을 포함한 반복적 수치 해석을 통해 에너지 구간별 스펙트럼을 구하였으며 에너지구간은 2keV로 하였다. 재구성한 에너지분포를 이용하여 계산된 투과선량과 측정투과선량의 비교는 두 광자에너지에서 모두 좋은 일치를 보였다. 에너지구간별 분할조사선량의 반복적 계산에 근거를 둔 수치해석은 흡수체의 감쇄된 선속으로부터 X선의 에너지스펙트럼을 매우 유용하게 결정할 수 있음을 보여주었다.

• 대한방사선기술학회지:방사선기술과학
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• 제8권1호
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• pp.87-105
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• 1985

• 대한방사선기술학회지:방사선기술과학
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• 제8권1호
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• pp.77-85
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• 1985

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 추계학술발표회요약집
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• pp.311.1-311
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• 2001

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 추계학술발표회요약집
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• pp.310.2-310
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• 2001