• Journal of radiological science and technology
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• v.28 no.2
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• pp.117-122
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• 2005

According to the Para. 5 of Art 2 of the Korean Nuclear Safety Regulations, which was revised in 1999, internal dose assessment as well as external one should be performed by law for employees at a nuclear power plant from 2003, and their estimate errors should also be within 50%. Thus, more accurate internal dosimetry becomes important. Corresponding to such regulation revision, we are developing a more accurate thyroid-uptake internal dosimetric system and have developed a Monte Carlo simulation code, the so-called CALEFF, to calculate the detection efficiency of the dosimetric system. In this paper, we calculated detection efficiencies with various test conditions by using the CALEFF code and discussed their characteristics. We may use the detection efficiency calculated by the code in calibrating the thyroid internal dose from measured data.

• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.202-207
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• 2013

Bioimpedance involves a lot of information related to living tissue. If there is alteration in bio tissue, its electrical characteristics also change. It is to study electrical characteristics of pork tenderlion in using a HP-4194A Impedance/Gain-phase analyzer instrument and electrical characteristics changes by graded radiation exposure dose. The results were as follow 1. Electrical characteristics of pork tenderlion in repeated measurement had high precision within ${\pm}5$% of coefficiency of variability. 2. During the measurement impedance absolute value and phase alteration did not show statistically significant difference.(p>0.05) 3. While impedance phase of electrical characteristics associated with frequency change was almost stable, impedance absolute value was in inverse proportion to frequency that means high inverse correlation of -0.096(r). 4. Impedance absolute value dropped in radiation exposure dose. The alteration of the value did not show statistically significant difference in 1 Gy, 2 Gy and 4 Gy.(p>0.05) However in radiation exposure dose of 10 Gy, the decrease of impedance absolute value was significantly different.(p<0.05) 5. Impedance phase according to radiation exposure dose change did not show statistically significant difference in 1 Gy, 2 Gy, 4 Gy, and 10 Gy(p>0.05).

• Radioisotope journal
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• v.15 no.3
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• pp.78-92
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• 2000

낮은 선량의 방사선피폭으로 인한 건강 위해의 여부에 대하여 과학적 현황을 고찰하였다. 선량과 영향 사이에 문턱 없는 선형비례 모델(LN-T모델)에 대해 역학적, 수학적, 방사선생물학적 측면의 긍정적 논리와 호메시스, 적응반응, 통계적 관점의 비판적 논거를 대비하여 평가하였다. 방사선 피폭이력자에게 발현한 확률적 영향 특히 백혈병을 포함한 암에 대해 그 질환의 방사선 인과성 판단에 대한 애로와 접근 방향을 논의하였다. 객관적인 평가 지표의 하나로 기인확률(PC)을 적용하되 근로자에 대한 제도적 배려 등 고려할 사항을 논의하였다.

• The Journal of the Korea Contents Association
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• v.8 no.8
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• pp.176-187
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• 2008

As the radiological medical instruments have been competitively developed in recent years, its utilization for the patient treatment has been expanded. The medical examination using the radiation has been gradually increased, so that it is recognized as a significant factor of increasing the radiation exposure. In this study, the recognition about the radiation exposure was analyzed for 555 gynecologic patients in 8 secondary and tertiary medical centers in Gyeongbuk from November 17 to April 19, 2007. The results are followed. There was a significant difference on the recognition for the radiation by age and education (p<0.05), There was the significant difference in the recognition about the radiological instruments by age and occupation (p<0.05), and there was the significant difference in the information identification & analysis by age and occupation (p<0.05). As the result of analyzing a correlation of the radiation's harmfulness, recognition, psychological state and exposure prevention, there was the correlation of 0.572 between the harmfulness and recognition, the correlation of 0.740 between the harmfulness and the psychological state, and the correlation of 0.477 between the harmfulness and the exposure prevention. It was statistically very significant (p<0.01). But, there was no significance with the radiological instrument and information identification (p>0.05). As the result of the study, it could be known that the mental threat factor was more included than the physical threat from the position of gynecologic patients who were sensitive to the radiation. Accordingly, radiological technologist who manages the radiation needs to let the patient or its guardians recognize the degree of physical harmfulness exactly.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.3-12
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• 2011

Purpose: With increasing medical use of radiation and radioactive isotopes, there is a need to better manage the risk of radiation exposure. This study aims to grasp and analyze the individual radiation exposure situations of radiation-related workers in a medical facility by specific job, in order to instill awareness of radiation danger and to assist in safety and radiation exposure management for such workers. Materials and Methods: From January 1, 2010 December 31, 2010, medical practitioners working in the radiation is classified as a regular personal radiation dosimetry, and subsequently one year 540 people managed investigation department to target workers, dose sectional area, working period, identify the job function-related tasks for a deep dose, respectively, the annual average radiation dose were analyzed. Frequency analysis methods include ANOVA was performed. Results: Medical radiation workers in the department an annual radiation dose of Nuclear and 4.57 mSv a was highest, dose zone-specific distribution of nuclear medicine and in the 5.01~19.05 mSv in the high dose area distribution showed departmental radiation four of the annual radiation dose of Nuclear and 7.14 mSv showed the highest radiation dose. More work an average annual radiation dose according to the job function related to the synthesis of Cyclotron to 17.47 mSv work showed the highest radiation dose, Gamma camera Cinema Room 7.24 mSv, PET/CT Cinema Room service is 7.60 mSv, 2.04 mSv in order of intervention high, were analyzed. Working period, according to domain-specific average annual dose of radiation dose from 10 to 14 in oral and maxillofacial radiology practitioners as high as 1.01~3.00 mSv average dose showed the Department of Radiology, 1-4 years, 5-9 years, respectively, 1.01 workers~8.00 mSv in the range of the most high-dose region showed the distribution, nuclear medicine, and the 1-4 years, 5-9 years 3.01~19.05 mSv, respectively, workers of the highest dose showed the distribution of the area in the range of 10 to 14 years, Workers at 15-19 3.01~15.00 mSv, respectively in the range of the high-dose region were distributed. Conclusion: These results suggest that medical radiation workers working in Nuclear Medicine radiation safety management of the majority of the current were carried out in the effectiveness, depending on job characteristics has been found that many differences. However, this requires efforts to minimize radiation exposure, and systematic training for them and for reasonable radiation exposure management system is needed.

• 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 the korean academy of Pediatric Dentistry
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• v.39 no.3
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• pp.273-279
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• 2012

Purpose : This study was aimed to calculate effective dose from cone beam CT and compare effective dose from periapical and panoramic radiography for mesiodens. Materials and Methods : Upper anteiror periapical, panoramic radiography and cone-beam CT were taken for diagnosis of mesiodens. The effective dose were calculated by using an anthropomorphic phantom loaded with thermoluminescent dosimeters at the 23 sites related to sensitive organs. Results : The highest absorbed doses were received by the mandibular body, parotid gland and cheek from periapical, panoramic and cone-beam CT, respectively. The effective doses for periapical, panoramic radiography and cone-beam CT measured 2, 18 and 48 ${\mu}Sv$. Conclusion : Cone-beam CT, although providing additional diagnostic benefits, exposes patients to higher levels of radiation than conventional periapical and panoramic radiography.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.179-182
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• 2017

Cerebral nervous system intervention procedures have been reported frequently due to radiation exposure such as skin baldness, hair loss, and redness due to prolonged procedures. Therefore, the bismuth shield designed to reduce the radiation exposure of the target organ located in the anterior part of the human body sensitive to skin and radiation sensitivity during CT (computed tomography) scan is applied to the cerebral vascular system intervention by ergonomic design, To reduce the radiation dose of sensitive scalp, we propose a study.

• Journal of the Korean Society of Radiology
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• v.13 no.2
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• pp.291-296
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• 2019

Nuclear medicine have often used to diagnose cancers. The main absorbed dose from radiation to a radiation worker resulted from open radioisotopes. Methods for reducing the radiation dose to a radiation worker from radioisotopes injected to patients were studied. The shield device of 0.2 mmPb was manufactured as a size of $300mm{\times}500mm{\times}150mm$. By using dosimeters of Nanodot, the absorbed doses for thyroid, chest and genital organ were measured with and without a shielding device and with syringe shield and shielding device together. The highest absorbed dose of 0.908 mGy reduction of 20.8% as 0.719 mGy was in the genital organ by using the syringe shield and a shielding device together. A effective dose for a radiation worker during 1 year was expected to 1.223 mSv at the chest, which was decrease as 0.994 mSv by shielding device and syringe shield together. When open radioisotope is injected to a patient for examination, the only use of a shielding device results in the reduction of radiation dose to radiation workers.

• Proceedings of the KIEE Conference
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• 2000.11d
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• pp.724-726
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• 2000

일반적으로 개인방사선감시에 열형광선량계와 필름배지가 공식 개인선량계로 이용되어 왔고 현재까지도 가장 보편적으로 사용되고 있다. 하지만 최근에는 Si 다이오드와 G-M관을 이용한 능동형 개인피폭선량계가 개발 보급되고 있다. 개인피폭선량계는 누적선량을 실시간으로 알 수 있다는 장점을 가지고 있을 뿐만 아니라 선량률에 관한 정보도 제공하므로 높은 비용부담에도 불구하고 피폭관리의 용이함으로 인해 주목을 받고 있다. 따라서 본 연구는 수입에 의존해 온 개인피폭선량계를 대체하기 위해 반도체형 방사선 검출기를 설계하여 다양한 서비스를 부가할 수 있는 개인피폭선량계를 자체개발고, 선량계의 운영 및 판독을 위한 장치를 개발하였다.