• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.1015-1024
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• 2019

In the medical field, X-rays are essential in the diagnosis and treatment of diseases, and the use of X-rays continues to increase with the development of imaging technology, but X-rays have the disadvantage of radiation exposure. Although lead protection tools are used in clinical practice to protect against radiation exposure, lead is classified as a heavy metal and can cause harmful reactions such as lead poisoning. Therefore, the purpose of this study is to investigate the usefulness of the shield fabricated using materials of FDM (Fused Deposition Modeling) 3D printer. In order to confirm the filament's line attenuation factor, phantoms were fabricated using PLA, XT-CF20, Wood, Glow and Brass, and CT scan was performed. And the shielding sheet of 100 × 100 × 2 mm size was modeled, the dose and shielding rate was measured by using a diagnostic X-ray generator and irradiation dose meter, and the shielding rate with lead protection tools. As a result of the experiment, the CT number of the brass was measured to be the highest, and the shielding sheet was manufactured by using the brass. As a result of confirming with the diagnostic X-ray generator, the shielding rate was increased in the shielding sheet having a thickness of 6 mm upon X-ray irradiation under the condition of 100 kV and 40 mAs. It measured by 90% or more, and confirmed that the shielding rate is higher than apron 0.25 mmPb. As a result of this study, it was confirmed that the shield fabricated by 3D printing technology showed high shielding rate in the diagnostic X-ray region. there was.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.251-256
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• 1999

대전력을 사용하는 제강공장의 L/F설비에서 발생되는 강자계를 효율적으로 차폐하기 위하여 L/F주위의 자기장 분포를 유한해석법을 이용한 사용해석도구인 ANSYS 5.3 3차원 자기장해석기를 통해 해석하고 그 결과를 평판형태의 차폐체에 적용시키고자 하였다. 분석결과, L1 및 L2가 각각 2.7 및 2.9m 이려 높이가 3.5m인 2중차폐체(1차측 차폐: 1mmt의 전기강판, 2차측차폐: 1mmt의 Fe-Ni alloy sheet)를 설치하는 거싱 최적의 처폐방안으로 도출되었다.

• 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 radiological science and technology
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• v.39 no.4
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• pp.493-499
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• 2016

In this study, C-Arm equipment is being used as we intend to verify the exposure dose on the operator by the scattering rays during the operation of the C-Arm equipment and to provide an effective method of reducing the exposure dose. Exposure dose is less than the Over Tube method utilizes the C-arm equipment Under Tube the scheme, The result showed that the exposure dose on the operator decreased with a thicker shield, and as the operator moved away from the center line. Moreover, as the research time prolongated, the exposure dose increased, and among the three affixed location of the dosimeter, the most exposure dose was measured at gonadal, then followed by chest and thyroid. However, in consideration of the relationship between the operator and the patient, the distance cannot be increased infinitely and the research time cannot be decreased infinitely in order to reduce the exposure dose. Therefore, by changing the thickness of the radiation shield, the exposure dose on the operator was able to be reduced. If you are using a C-Arm equipment discomfort during surgery because the grounds that the procedure is neglected and close to the dose of radiation shielding made can only increase. Because a separate control room cannot be used for the C-Arm equipment due to its characteristic, the exposure dose on the operator needs to be reduced by reinforcing the shield through an appropriate thickness of radiation shield devices, such as apron, etc. during a treatment.

• Progress in Medical Physics
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• v.23 no.4
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• pp.234-238
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• 2012

A tumor on the eyelid is often treated using a high-energy electron beam, with a metallic eye shield inserted between the eyelid and the eyeball to preserve the patient's sight. Pretreatment quality assurance of the inner eyelid dose on the metallic shield requires a very small dosimetry tool. For enhanced accuracy, a flexible device fitting the curved interface between the eyelid and the shield is also required. The radiochromic film is the best candidate for this device. To measure the doses along the curved interface and small area, a 3-mm-wide strip of EBT2 film was inserted between the phantom eyelid and the shield. After irradiation with 6 MeV electron beams, the film was evaluated for the dose profile. An acrylic eye shield of the same size as the real eye shield was machined, and CT images free from metal artifacts were obtained. Monte Carlo simulation was performed on the CT images, taking into account eye shield material, such as tungsten, aluminum, and steel. The film-based interface dose distribution agreed with the MC calculation within 2.1%. In the small (millimeter scale) and curved region, radiochromic film dosimetry promises a satisfactory result with easy handling.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.5-8
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• 2010

Opened a court in February 10, 2006, a rule of safety management of the diagnosis radiation system was promulgated for safety of the radiation worker, patients and patients' family members. The purpose of this rule is to minimize the risk of being exposed to radiation during the process of handling X-ray. For this reason, we manufactured shielding device of mobile X-ray unit collimator for diminution of skin dose. Shielding device is made to a thickness of Pb 0.375mm. For portable chest radiography, we measured skin dose 50cm from center ray to 200cm at intervals of 20cm by Unfors Xi detector. As a result, a rule of safety management of the diagnosis radiation system has been strengthened. But there are exceptions, such as ER, OR, ICU to this rule. So shielding device could contribute to protect unnecessary radiation exposure and improve nation's health.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.279-287
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• 2020

Recently, interest in radiation protection is increasing because of the occurrence of accidents related to exposure dose. So, the nuclear safety act provides to install the shields to avoid exceeding the dose limit. In particular, when the worker conducts the non-destructive testing (NDT) without the fixed shielding structure, we should monitor the access to the workplace based on a constant dose rate. However, when we apply for permits for NDT work in these work environments, the consideration factors to the estimation of the distance and exposure dose are not legally specified. Therefore, we developed the excel model that automatically calculates the distance, exposure dose, and cost if we input the factors. We applied the assumption data to this model. As a result of the application, the distance change rate was low when the thickness of the lead blanket and collimator is above 25 mm, 21.5 mm, respectively. However, we didn't consider the scattering and build-up factor. And, we assumed the shape of the lead blanket and collimator. Therefore, if we make up for these limitations and use the actual data, we expect that we can build a database on the distance and exposure dose.

• Journal of radiological science and technology
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• v.41 no.5
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• pp.397-403
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• 2018

Mobile X-ray generators are used not in the radiation area but in open space, which causes the exposure of secondary radiation to the healthcare professionals, patients, guardians, etc., regardless of their intentions. This study aimed to investigate the shielding effect of the developed radiation restrictor to block the secondary radiation scattered during the use of mobile X-ray generator. Upon setting the condition of mobile X-ray generator with chest AP, spatial doses were measured by the existence of human equivalent phantom and radiation restrictor, and measured by the existences of phantom and radiation restrictor at the same length of 100 cm. Measurements were taken at intervals of 10 cm every $30^{\circ}$ from $-90^{\circ}$ (head direction) to $+90^{\circ}$ (body direction). Upon the study results, spatial doses in all direction were increased by 45% on average when using phantom in the same condition, however, they were decreased by 64% on average when using the developed radiation restrictor. The dose at 100 cm from the center of X-ray was $3.0{\pm}0.08{\mu}Gy$ without phantom and was increased by 40% with $4.2{\pm}0.08{\mu}Gy$ after phantom usage. The dose when using phantom and the developed radiation restrictor was $1.4{\pm}0.08{\mu}Gy$, which was decreased by 66% compared to the case without using them. Therefore, it is considered the scattered radiation can be shielded at 100-150 cm, the regulation of the distance between beds, effectively with the developed radiation restrictor when using mobile X-ray generators, which can lower the radiation exposure to the people nearby including healthcare professionals and patients.

• Journal of the Korean Society of Radiology
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• v.7 no.5
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• pp.353-358
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• 2013

Recently, the Percutaneous Coronary Intervention has become a main treatment for treating Coronary because of increase of Circulatory Disease. Because of this reason, the increase of intervention using radiation causes the radiation exposure to workers. Therefore, the latent radiation injury can be increased. Thus, this study/experiment measured around under knee whether using radiation collimator shielding or not. We measured the exposure does by the experiment methods which are using 60kV, 200mA, and 10ms of Automatic exposure conditions and using the major method of the Cinefluography of Coronary in our hospital. As the result of right coronary artery test cases, LAO $30^{\circ}$ when the curtains if you use lead 98.4%, $Cranial30^{\circ}$ 98.3% have a protective effect of the radiation. left circumflex coronary artery test cases, Caudal $30^{\circ}$ if the shielding effect of 90.2%, Caudal $30^{\circ}LAO$ $30^{\circ}$ 88.7% have a protective effect of the radiation. left anterior descending artery test cases, Cranial $30^{\circ}$ 98.3%, Cranial $30^{\circ}RAO$ $30^{\circ}$ 80.3%, Cranial $30^{\circ}$LAO $30^{\circ}$ 98% of the radiation has a protective effect. OS(Spider view) in the case of test Caudal $40^{\circ}LAO$ $40^{\circ}$ 71.2% appeared to have the effect of radiation shielding. For these reasons, radiation workers need to be aware on taking care of their radiation exposure by using the radiation collimator shielding even though it is uncomfortable for them.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1487-1490
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• 2007

디지털 위성방송의 시작과 더불어 본격적인 데이터 방송의 시대가 열렸다. 데이터방송이 시작 되면서 데이터방송용 양방향 콘텐츠에 대한 수요가 급속하게 증가하고 있다. 하지만 양방향 콘텐츠 개발에 필요한 저작 도구 및 검증 시스템은 아주 초보적인 수준에 머물러 있는 것이 현실이다. 그러나 방송의 특성상 콘텐츠 상에서의 오류는 방송 사고에까지 이를 수 있는 심각한 상황이 연출 될 수 있다. 본 연구 팀은 이러한 DTV 콘텐츠 개발 요구에 부응하여, 개발자의 콘텐츠 개발 및 사업자 또는 기관에서의 콘텐츠 검증이 원활이 이루어 질수 있도록 하는 양방향 콘텐츠 검증 시스템을 개발 중이다. 양방향 콘텐츠 검증 시스템은 Java 컴파일러, 디버거, 미들웨어, 가상머신, 그리고 IDE 등으로 구성된다. 본 논문에서 제시한 자바 컴파일러는 양방향 콘텐츠 검증 시스템에서 데이터 방송용 자바 애플리케이션(Xlet)을 컴파일하여 에뮬레이팅 하거나 런타임 상에서 디버깅이 가능하도록 하는 바이너리형태의 class 파일을 생성한다. 이를 위해 Java 컴파일러는 *.java 파일을 입력으로 받아 어휘 분석과 구문 분석 과정을 거친 후 SDT(syntax-directed translation)에 의해 AST(Abstract Syntax Tree)를 생성한다. 클래스링커는 생성된 AST를 탐색하여 동적으로 로딩 되는 파일들을 연결하여 AST를 확장한다. 의미 분석과정에서는 확장된 AST를 입력으로 받아 참조된 명칭의 사용이 타당한지 등을 검사하고 코드 생성이 용이하도록 AST를 변형하고 부가적인 정보를 삽입하여 ST(Semantic Tree)를 생성한다. 코드 생성 단계에서는 ST를 입력으로 받아 이미 정해 놓은 패턴에 맞추어 Bytecode를 출력한다.ovoids에서도 각각의 점들에 대한 선량을 측정하였다. SAS와 SSAS의 직장에 미치는 선량차이는 실제 임상에서의 관심 점들과 가장 가까운 25 mm(R2)와 30 mm(R3)거리에서 각각 8.0% 6.0%였고 SAS와 FWAS의 직장에 미치는 선량차이는 25 mm(R2) 와 30 mm(R3)거리에서 각각 25.0% 23.0%로 나타났다. SAS와 SSAS의 방광에 미치는 선량차이는 20 m(Bl)와 30 mm(B2)거리에서 각각 8.0% 3.0%였고 SAS와 FWAS의 방광에 미치는 선량차이는 20 mm(Bl)와 30 mm(B2)거리에서 각각 23.0%, 17.0%로 나타났다. SAS를 SSAS나 FWAS로 대체하였을 때 직장에 미치는 선량은 SSAS는 최대 8.0 %, FWAS는 최대 26.0 %까지 감소되고 방광에 미치는 선량은 SSAS는 최대 8.0 % FWAS는 최대 23.0%까지 감소됨을 알 수 있었고 FWAS가 SSAS 보다 차폐효과가 더 좋은 것으로 나타났으며 이 두 종류의 shielded applicator set는 부인암의 근접치료시 직장과 방광으로 가는 선량을 감소시켜 환자치료의 최적화를 이룰 수 있을 것으로 생각된다.)한 항균(抗菌) 효과(效果)를 나타내었다. 이상(以上)의 결과(結果)로 보아 선방활명음(仙方活命飮)의 항균(抗菌) 효능(效能)은 군약(君藥)인 대황(大黃)의 성분(成分) 중(中)의 하나인 stilbene 계열(系列)의 화합물(化合物)인 Rhapontigenin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이는 한의학(韓醫學) 방제(方劑) 원리(原理)인 군신좌사(君臣佐使) 이론(理論)에서 군약(君藥)이 주증(主症)에 주(主)로 작용(作用)하는 약물(藥物)이라는 것을 밝혀주는 것이라고