• Proceedings of the Korea Contents Association Conference
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• 2012.05a
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• pp.179-180
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• 2012

향후 21세기는 지금껏 경험해 보지 못한 고령화 사회로서, 골다공증은 심혈관 질환 및 당뇨병에 이어 가장 중요한 노인 질환으로 대두 되어질 것이다. 그러므로 골다공증에 대한 조기 진단과 예방을 위한 진단방법은 매우 중요하나 잘못된 진단으로 조기발견을 놓칠 수 있게 된다. 여러장비 중 Radiographic Absorptiometry는 단순 X선 촬영을 통해서 피질골(손의 metacapal bone)의 두께를 측정하는 방법으로 간단하지만 약간의 오류를 갖고 있어 검사부위의 변환을 통해 결과값을 연구하고자 한다.

• Journal of the Korean Society of Radiology
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• v.14 no.7
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• pp.907-913
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• 2020

There have been continuous controversies on medical X-ray protection and numerous researchers have been trying to prevent unnecessary exposure to radiation. As X-ray passes through the patient and obtains an image, it creates scattered ray due to interactions such as photoelectric effect and Compton scattering with the subject. As a result, both medical radiation staff and patient are exposed to unnecessary radiation on areas other than the target area. In response, this study will be assuming a body of a female, radiating X-ray on the phantom under the conditions of lumbar spine AP test, and measuring scattered ray around breasts and thyroid glands. Then, The experiment results were as follows. After application of non-shielding material, the average of scattered ray was 0.88 mR in thyroid measurement, 3.34 mR, Lt Axillary 3.54 mR, and Rt Axillary 3.03 mR in mamonary measurement but, After application of shielding material, the average of scattered ray was 0.16 mR in thyroid measurement, 0.60 mR, Lt Axillary 0.64 mR, and Rt Axillary 0.54 mR in mamonary measurement showing average scattered ray protection effect of about 82%. This study suggested the manufacturing method of a Jelly-type shielding material, identified the possibilities of researches on mixing various substances with radiology field, and verified the usability of the Jelly-type shielding material as a substitute for existing protection tools.

• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.351-364
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• 2020

Missed lung cancers on chest radiograph (CXR) may delay the diagnosis and affect the prognosis. CXR is the primary imaging modality to evaluate the lungs and mediastinum in daily practice. The purpose of this article is to review chest radiographs for common blind spots and highlight the importance of various radiologic presentations in primary lung cancer to avoid significant diagnostic errors on CXR.

• Journal of radiological science and technology
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• v.30 no.4
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• pp.349-356
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• 2007

Conclusions below are drawn after survey date from 1,969 samplers of mammography and 1,531 breast ultrasound for 10 months, from 1 July 2006 to 30 April 2007. 1. Ages between 40 and 50 of samplers take the largest part of age distribution, and 68.57% of mammography and 71.32% of samplers are fallen under the category. 2. Samplers judged by diseased patients are 31.95% samplers of mammography and 45.79% samplers of breast ultrasound. 3. Age distributions of diseased patients were from 30 to 60 in mammography, 30 to 50 in breast ultrasound. 4. Breast ultrasound shows little difference between left side and right side of diseased part, but mammography shows significant diseased part in both sides. 5. As a result of reading examination, there is higher probability of detection in order of Calcification, Nodular, Mass in mammography. And Cyst, Nodular, Mass in breast ultrasound. 6. As a reading examinations, probability of judging a certain disease in high in mammography, but breast ultrasound shows 1 or 2 kinds of disease.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.3
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• pp.172-180
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• 1998

It is attempted to verify the Quantitative relationship between fracture mechanical parameters (${\Delta}K$, $K_{max}$) and X-ray parameters (residual stress, half-value breadth) of A12009-15v/o $SiC_w$ composite, and normalized SS41 steel. In this study, fatigue crack propagation test were carried out and X-ray diffraction was applied to fatigue fractured surface in order to investigate the change of residual stress and half-value breadth on fatigue fractured surface. And it is loaded prestrain to each tensile specimen, A12009-15v/o $SiC_w$ composite(0.3, 0.5, 1, 1.5, 2%) and normalized SS41 steel(0.63, 2.25, 7.50, 13.7, 20%), for investigating plastic strain rate using nondestructive measurement method. X-ray diffraction was applied to the prestrained tensile specimens in order to measure the change of residual stress and half-value breadth.

• Journal of radiological science and technology
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• v.40 no.2
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• pp.311-316
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• 2017

Generally assessing bone mineral density (BMD) were performed on dual energy X-ray absorptiometry (DEXA) the same as dual energy CT (DECT) with a rapid-kVp switching. The purpose of this study is to compare the different of BMD value between DEXA and DECT method, and evaluate usefulness of DECT method. Using scanner for BMD measurements were GE, Healthcare Discovery 750 HD for DECT and Hologic QDR 4500W for DEXA. For compare BMD value in each method, scanned lumbar spine phantom and subjects visiting Korean National Cancer Center from April 2015 to December 2015, records of 50 patients. This study was approved by the Institutional Review Board. The mean BMD value measures for spine phantom and for subjects in each scanners presented strong correlation (r=0.948 with p<0.05 for phantom; r=0.635 with p<0.05 and Kendall's tau $({\tau})=0.46$ with p<0.05 for subjects) and linear relationship between DECT and conventional DEXA. DECT technique for BMD measurement will provide a very useful methodology without additional radiation dose.

• Journal of the Korean Society of Radiology
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• v.11 no.4
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• pp.253-262
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• 2017

In lateral projection imaging method of knee joint, a method that adjusts the incidence angle of central X-ray toward the head side to $5{\sim}7^{\circ}$ in true lateral position which is existing recommended is called imaging method A, Method of imaging the central X-ray perpendicular to the horizontal plane of the examination table toward the knee is called imaging method B, and a method in which the central X-ray is perpendicularly applied to the joints while the lateral side of the distal tibia is compensated by radiolucent materials is called as method C. After tests each imaging method to classified study subject respectively, the joint space distance and the distance between lateral and medial condyle of femur were measured and compared as the quantitative index from the three imaging methods. In addition, the convenience of each imaging method was confirmed through questionnaires to practician. According to the result of the quantitative index, there is no statistically significant difference in imaging method A and C(p>0.05). However, imaging method B showed a significant difference in both A and C(p<0.05). As a result of evaluating the convenience of the imaging method, imaging method A was relatively assessed lower in all items than imaging methods B and C, and as a small difference, imaging method B is assessed higher than C. In this study suggested new knee joint lateral projection imaging method, by using a simple support device, could describe joint space as not much different as existing recommended method without some complex process, and could increase convenience of the practician in the process of the imaging.

• 전기의세계
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• v.38 no.8
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• pp.19-25
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• 1989

현재 전세계적으로 퍼져있는 NMR-CT 시스템의 수를 살펴보면 약 370여기가 설치.운영되고 있으며 앞으로 계속 늘어날 전망이다. 국내에서는 1988 한국과학기술원과 금성통신에 의해 자체 개발된 2.0 Tesla 강자장 시스템이 최초로 서울대학병원에 설치 가동된 이래 여러병원에서 시스템들이 설치중에 있다. 첨단의로 진단장치로서의 핵자기 공명 영상법은 그 영상을 통하여 기존의 진단 장치보다 우월함을 증명하고 있으며 초음파 검사나 동위원소 검사 및 X선 전산화 단층 촬영술들을 장점을 두루 지니면서 그 영상법의 다양성 때문에 앞으로의 연구 및 발전에 대한 전망은 아주 밝다고 할 수 있다. 따라서 앞으로의 종합 영상 의료 진단 장치는 이 NMR-CT가 중심이 되어 발전할 것이라고 단언해도 무리한 생각은 아닐 것이다.

• The Journal of the Korea Contents Association
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• v.13 no.3
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• pp.198-203
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• 2013

The purpose of this study is to investigate the scattered dose of X-ray at a distance of 30cm from the area to be examined when X-ray field is the most optimized and maximized when X-ray is performed on hand, skull and abdomen. As a result of scattered dose of X-ray on hand, skull and abdomen, first, when X-ray field was the most optimized upon adult X-ray examination, it was $0.08{\mu}Sv$, $4.39{\mu}Sv$ and $5.56{\mu}Sv$, respectively. When x-ray field was maximized, it was $0.58{\mu}Sv$, $33.47{\mu}Sv$ and $35.93{\mu}Sv$, respectively. Second, when X-ray field was the most optimized upon pediatric X-ray examination, it was $0.40{\mu}Sv$, $14.51{\mu}Sv$ and $18.86{\mu}Sv$, respectively. When x-ray field was maximized, it was $2.78{\mu}Sv$, $107.40{\mu}Sv$ and $117.52{\mu}Sv$, respectively(P<0.001). As a result, when the size of X-ray field was decreased down to be necessary and optimal upon X-ray examination, emission of scattered X-ray around specimen is reduced approximately 6-7 times as much as that when it was maximized.

• Journal of the Korean Wood Science and Technology
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• v.34 no.1
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• pp.15-22
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• 2006

ln order to manage efficiently many ancient wooden buildings, which have been preserved as cultural properties in Korea, the internal state of wood members should be evaluated exactly and periodically by a NDE (non-destructive evaluation) method. A research project was planned to develop an X-ray CT (computed tomography) system as a NDE method for wood, which could be easily applied in field. This paper includes the first part of this project. First of all, to establish a measuring procedure of wood density using X-ray radiography, the correlation between X-ray intensity and the film brightness was evaluated. Also, initial X-ray intensity was quantified with various radiate conditions controlled by the tube voltage and tube current. And then, the effects of density, annual ring angle, and thickness on the mass attenuation coefficient of wood were examined. Finally, Beer's law was modified with the above results and adopted to calculate the density of wood. As a result of this study, the measuring procedure of wood density was established using a portable soft X-ray device and this procedure was verified with some small wood specimens. This results will he used valuably for the following researches to develop a portable X-ray CT system.