• Journal of Radiation Protection and Research
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• v.29 no.1
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• pp.17-23
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• 2004

In order to save time and money needed in the purchase commonly used gamma-ray standard sources, a new radioactive standard source was manufactured by the neutron activation of some regent in the research reactor HANARO. The source was manufactured with an aqueous solution by mixing and dissolving the irradiated reagents. The manufactured source was compared with a commercial standard source. It was confirmed that it could be used as an efficiency calibration source. Also, in order to compare the variation of efficiency due to the volume difference for various containers used in radioactivity assay, the efficiency variation as a function of sample volume was investigated.

• The Journal of Engineering Geology
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• v.25 no.2
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• pp.281-290
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• 2015

Log density data were collected and compared with the core density data throughout the southern Korean Peninsula. The comparison reveals that the log densities obtained from gamma-gamma log are much lower than the core densities obtained from laboratory density measurement of core samples. The anomalously low log densities can be attributed to the small-source density log data. Correlation analysis reveals differences between densities derived from the two methods, indicating that a data quality problem arises when using small-source log data. The problem is probably due to the fact that small-source data have not been obtained under ideal conditions for maintaining the appropriate relationship between gamma response and formation density. The frequency distribution characteristics of formation density in the southern Korean Peninsula could be determined using the core and the standard-source log data which are well-correlated.

• Progress in Medical Physics
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• v.12 no.2
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• pp.141-146
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• 2001

It is well known that assurance of the radiation therapy needs for an accuracy of $\pm$ 5 % in the delivery of an absorbed dose to target volume. Therefore, the dose evaluation of brachytherapy source and/or linear accelerate beam must be a stability with accuracy. In an advanced country, they recommended to use the radioactive check source for reference air ionization chamber for a stable response of radiation field chamber. In this experiments, the radioactive source Sr-90 and PR-05 air ionization chamber were used for standard source and reference ion chamber. The response of reference ion chamber showed as an 1.000$\pm$ 0.010 uncertainty for 10 years long and the evaliuation f dose discrepancy of clinical field ion chamber showed as 0.997 $\pm$0.011 in a $^{60}$ Co brachytherapy soruce. In our experiments, we can assuarance the long halflife standard source is reliable to preserve the calibration factor of reference chamber in stability.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.801-805
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• 1998

1000 MWe 국내 표준형 원전을 대상으로 노심이 손상되는 각종 중대사고 시나리오에 대하여 방사선원항 특성을 평가하기 위하여, 2단계 확률론적 안전성 평가 방법론에 따라 방사선원 방출군을 정의하고 원전 중대사고 발생시 격납건물 손상을 가정하여 각 방출군별로 격납건물 외부로 방출되는 방사능 방출율을 정량화하였다. 도출된 19개의 그룹중에서 방출률이 작거나 발생빈도가 낮은 7개를 제외하고 12가지 대표 사고경위에 대하여 계산을 수행하였으며, 분석결과는 격납건물 내에서 감쇄효과가 작은 증기발생기 세관 파단사고, 격납건물 격리 실패사고 및 조기 격납건물 파손사고 둥이 상대적으로 큰 방사능 방출량을 보여주었다

• The Korean Journal of Nuclear Medicine Technology
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• v.24 no.1
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• pp.20-26
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• 2020

Purpose It is intended to figure out the errors derived from changes in depth and volume when measuring the Standard source and ^99mTc-pertechnetate by using a Dose calibrator. Then recommend appropriate measurement depth and volume. Materials and Methods As a Dose calibrator, CRC-15βeta and CRC-15R (Capintec, New Jersey, USA) was used, and the measurement sources were ⁵⁷Co, ¹³³Ba, ¹³⁷Cs and ^99mTc-pertechnetate was also adopted due to its high frequency of use. The Standard source was respectively measured the changes according to its depth without changing the volume, in a range of 0 cm to 15 cm from the bottom of the ion chamber. ^99mTc-pertechnetate was measured at each depth by changing the volume with 0.1 mL, 0.3 mL, 0.5 mL, 0.7 mL and 0.9 mL Respectively. And the depth range was from 0 cm to 15 cm at the bottom of the ion chamber. Results In the case of Standard source ⁵⁷Co, ¹³³Ba, ¹³⁷Cs and ^99mTc-pertechnetate, there were significant differences according to the measurement depth(p<0.05). ^99mTc-pertechnetate has a negative correlation coefficient according to the depth, and the error of the measured value was negligible at a depth from 0 cm to 7 cm at 0.3 mL and 0.5 mL, and the range of error increased as the volume increased. Conclusion In clinical practice, it is sometimes installed differently than the Standard depth recommended by the equipment company. If it's measured at the recommended depth and volume, it could be thought that unnecessary exposure of the operator and the patient will be reduced, and more accurate radiation exams will be possible in quantitative analysis.

• Journal of Radiation Protection and Research
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• v.14 no.1
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• pp.66-70
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• 1989

In routine testing, the radioactive neutron sources are particularly suitable for producing standard. neutron fields. The ISO TC-85 has proposed neutron reference radiation for the calibration of neutron measuring devices used for radiation protection purposes. Radiation laboratory of KSRI has installed a standard irradiation facility using $^{252}Cf$ and $^{241}Am-Be$ sources for calibrating personal dosimeters according to the recommendations given in ISO TC-85. In this study, correction factors for calibration related to neutron scattering and anisotropy are obtained by experiments with commercial rem meter for demonstration purposes.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.63-68
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• 1996

열형광 선량계(TLD)를 사용한 피부 선량평가는 베타선의 에너지를 구분함으로 정확히 평가된다. 이는 차폐체에 의한 감쇄효과를 이용하는 방법으로 본 논문에서는 7개의 두께가 다른 알루미늄 차폐체를 사용하였고, TLD로는 미국 Teledyne Isotopes사의 LiF$_{7}$ 선량계를 채택하였다. 비상 베타 선량계의 베타선에 대한 특성실험을 위해 한국 원자력연구소가 확보 하고 있는 PTB 표준선원인 $^{90}$ Sr/ $^{90}$ Y (E$_{max}$=2.27MeV, E$_{avg}$=0.8MeV), $^{204}$Tl(E$_{max}$=0.76MeV, E$_{avg}$=0.26MeV), $^{147}$ Pm (E$_{max}$= 0.225MeV, E$_{avg}$=0.06MeV)에 대한 조사를 하였다. 이런 결과로 비상 베타 선량계의 표준 베타선원에 대한 보정계수와 소자별 반응비를 구할 수 있었고, 이것을 이용하여 미지의 베타선원에 대하여 정확한 선량평가를 하기위한 알고리즘을 개발하였다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.30-31
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• 2017

본 연구는 내항상선에 승선하는 외국인 선원을 대상으로 한 표준 해사한국어 교육과정의 설계를 위한 기초 연구이다. 현재 국내선원의 부족으로 외국인 선원이 증가함에 따라 의사소통 문제를 둘러싼 여러 논의가 진행 중이다. 본 연구의 최종 목표는 혼승 선박에서의 보다 원활한 의사소통을 위해 일상 업무의 수행에 필요한 주요 대화를 선정하여 이것을 외국인 선원을 위한 표준 해사한국어 교육과정에 반영하고자 하는 것이다. 이를 위해 여기에서는 문헌 연구와 설문 조사를 실시하여 부원의 일상 업무를 목록화하고 이들 업무의 중요도와 빈도를 조사하였다. 먼저 각국 대학에서 사용 중인 해사영어 교재와 내항상선의 외국인 선원을 교육하기 위한 교육 자료를 살펴봄으로써 1차적으로 공통되는 업무를 추출하였다. 다음으로 승선 유경험자로 구성된 전문가 위원회의 자문을 통해 업무의 범주를 설정하고 세부 업무 내용을 선정하였다. 마지막으로 설문조사를 실시하여 이들 업무의 중요도와 빈도를 조사하였다. 본 연구의 결과를 바탕으로 추후 연구에서 주요 대화를 선정하기로 한다.

• Journal of the Korean Society of Radiology
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• v.15 no.3
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• pp.307-312
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• 2021

In nuclear medicine, radioactive isotope tracers are administered to the human body to obtain and evaluate disease morphological information and biological function information. Dose calibrator is a device used to measure the radioactivity of a single nuclide in medical institutions. Administration of the correct dose to the human body acts as an important factor in diagnosis and treatment, and measurement through a dose calibrator before administration is the most important factor. Dose calibrator performs daily quality control after installation in each medical institution. Quality control is a means of guaranteeing quality control after installation, and is essential for improving the quality of treatment and promoting patient safety. Therefore, accurate and standardized performance evaluation methods should be established. In this study, 3D printing was used for quantitative evaluation of quality control by increasing the accuracy and standardization of quality control. When the 3D printer was installed and reproducibility was tested, the error range of the expected value and reading value decreased by 0.302% in the F-18 nuclide and 0.09% in the ^99mTc-pertechnate nuclide than when the 3D printer was installed. The error rate for other nuclides was also found to have a low error rate for reproducibility tests when 3D printing was installed.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.889-894
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• 1995

본 연구에서는 ANSI N13.32(1995)에서 제시한 손가락, 손목/발목 기준 팬텀(1)을 설계 제작하여 Teledye사의 말단선량계(finger와 wrist dosimeter)에 대한 방향의존성 실험을 수행하였다. 방사선원으로는 PTB 2차 베타표준선원 $^{204}$Tl(0.24 MeV), $^{90}$ sr/Y(0.8 MeV) 그리고 $^{l37}$ Cs(0.66 MeV) 표준 감마선원을 사용하였으며, 말단선량계로는 LiF Teflon(D-LiF-7-0.13)을 사용하였다. 90$^{\circ}$ 에서 $10^{\circ}$ 까지 20$^{\circ}$ 씩 수직과 수평으로 팬텀을 회전하여 정상각과 비정상각에 대한 상대응답을 제시하였다. 실험결과 90$^{\circ}$에서 모든 선량계는 잘 일치하였다. $^{90}$ Sr/Y은 50$^{\circ}$ 정도에서 다소 방향의존성이 적은 결과를 보였으며, $^{204}$ TI는 20$^{\circ}$에서 최소 13% 정도의 심한 방향의존성이 나타났다. 또한 $^{137}$Cs은 $10^{\circ}$에서도 최대 10.6% 정도의 적은 방향의존성을 나타냈다. 본 실험의 결과로부터 말단선량계는 저에너지와 낮은 투과 방사선[2]에서 심하게 방향의존성이 나타남을 알 수 있었다.