• 대한방사선방어학회:학술대회논문집
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• 2009.04a
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• pp.242-243
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• 2009

• Journal of the Korean Society of Radiology
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• v.6 no.1
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• pp.79-82
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• 2012

Iodine is one of important nuclides to be checked for radiation exposure after nuclear power facility accidents. After Chernobyl accident, it was observed that there is a greater amount of organic iodine in the atmosphere than inorganic iodine. In this study, we not only varied the amount of sample being exposed to $^{131}I$ and the duration of exposure to $^{131}I$ but also diluted the sample in distilled water and mixed the sample in kelp and liquid $^{131}I$ to measure and analyze the radiation detection levels. We concluded that the radiation levels were not high enough to be harmful to human body. The radiation from $^{131}I$ decreased over time, and we calculated the half life at 7-9 days. We found that the radiation from any sample containing $^{131}I$ was halved by up to 7days.

• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.172-173
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• 2009

• 대한방사선방어학회:학술대회논문집
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• 2009.04a
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• pp.150-151
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• 2009

• Journal of the Korean Society of Radiology
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• v.5 no.1
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• pp.5-10
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• 2011

Based on basic concept of detection limit, sample measurement time & background measurement time was considered, and MDA values according to background measurement time and sample measurement time in land samples(river soil, surface soil, drinking water, underground water, surface water, pine leaf, mugwort) analysis among environmental samples were compared. Seeing the water sample analysis result, it was shown that most of the samples were not detected, and most of the samples in land specimen analysis showed to be below the detection limit of "Ministry of Education, Science and Technology Announcement Je-2008-28-ho", but $^{137}Cs$ which is one of artificial radioactive nuclide was detected in some samples. It can be traced back to 1950s and 1960s when nuclear tests were carried out in atmosphere and catastrophic Chernobyl atomic power station accident that caused fallouts in the sky, and this is common level of detection that can be observed worldwide. Seeing the result that the $^{134}Cs$(which is a isotope of $^{137}Cs$, and it has relatively short half life) was not detected in all samples, it can be considered it doesn't affect to the operation of atomic power station.

• Journal of radiological science and technology
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• v.38 no.2
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• pp.163-170
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• 2015

The interest of the people in the radioactive contamination of the water has increased significantly and the study about analysis and management of radioactive materials are being actively conducted. And monitoring spots have been expanded to the range of public water as well as drinking water by publishing the rule of drinking water quality standards and examination in the Environmental Enforcement Ordinance No. 553 of Korea. In this study, US EPA was investigated as the foreign advanced cases and the way that is appropriate for the Korea was sought by analyzing investigate radionuclide, interval and management. As a result, in the selection part of investigate radionuclide, geological survey, status of nuclear power plants and the presence of the use of artificial radionuclides of the Korea should be investigated and additionally after the selection of a few radionuclides, the systems should be extended to cover all possible radionuclides by considering radioactive pollution levels in humans may be exposed due to the annual drinking water. In the part of the investigate interval, the concept(MCL, DL) should be set up for preventing concentration detection of above MCL and it needs to the maintenance and management. For example, when the concentration is more than MCL, it should be investigated on a quarterly and when the concentration is lower than MCL, it should be investigated to each different interval and management. And the US EPA divided the management area and make the roadmap for managing drinking water. The each classified area has been organized to match the state budget and labor force and the individual data have been managed effectively by HPGe, the NaI, TLD and so on.

• Journal of radiological science and technology
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• v.40 no.4
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• pp.605-611
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• 2017

The structure of the actual detector was computed using the code of the PENELOPE. Using the standard mixed sources (450, 1,000 ml), compare the effectiveness of each energy according to various densities and height of the PENELOPE computer simulation, and calculate the effectiveness of the various environmental specimens and apply them to various environmental specimens to determine the lower limit. The values obtained by the obtained value were obtained by applying the obtained efficiency to the actual environmental specimens and obtaining the lower limit values. The density correction factor is 1.155 g of the density correction factor of $0.4g/cm^3$ (59.54keV), 1.153 (661 keV), $1.06g/cm^3$ 1.064 (1,836.04keV), 1.03, and 1.033. It was confirmed that the radioactivity concentration of environmental samples decreased as the amount of specimen was measured increases, and the MDA value decreased as time measured increases.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.10
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• pp.1195-1200
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• 2019

This paper proposes a detection algorithm for group testing. Group testing is a problem of finding a very small number of defect samples out of a large number of samples, which is similar to the problem of Compressed Sensing. In this paper, we define a noiseless group testing and propose a probabilistic algorithm for detection of defective samples. The proposed algorithm is constructed such that the extrinsic probabilities between the input and output signals exchange with each other so that the posterior probability of the output signal is maximized. Then, defective samples are found in the group testing problem through a simulation on the detection algorithm. The simulation results for this study are compared with the lower bound in the information theory to see how much difference in failure probability over the input and output signal sizes.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.872-878
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• 1995

방사성폐기물 드럼내에 포함되어 있는 방사성 핵종의 양이 핵종분석장치로 측정할 수 있는 검출 하한치 이하이거나, 혹은 너무 높아 불감시간이 크게 증가될 경우에는 순수 Ge 검출기를 장착한 핵종분석장치로는 분석이 불가능하게 되므로 본 연구에서는 표면선량율과 Scaling Factor를 이용하여 드럼속에 포함되어 있는 핵종들의 양을 평가하는 방법을 제시하였으며, 불균일성이 높을 경우의 가능한 평가방법을 알아보기 위하여 점선원을 이용한 실험을 실시하였다. 그 결과 비균질 드럼에 대해서는 점선원을 이용한 자료를 이용하는 것이 합리적이고 기하학적 산술평균을 취함으로써 보다 정확도가 증가됨을 알 수 있었다. 그러나 그 오차범위는 -25%∼5.5%로서 실제보다 상당히 낮게 평가되는 경향이 있으므로 적절한 비균질성 보정인자를 적용할 필요가 있는 것으로 생각된다.

• The Korean Journal of Nuclear Medicine
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• v.21 no.1
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• pp.55-60
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• 1987

$Digoxin^{(R)}$을 복용하고 있지 않는 각27명의 만성 신부전 환자 및 신생아의 혈청에서 Gammacoat $Digoxin^{(R)}$ kit와 Amerlex Digoxin $RIA^{(R)}$ kit를 이용하여 digoxin과 교차 면역반응을 보이는 내인성 물질(이하 DLI: Digoxin-like Immunoreactivity)을 측정하여 다음의 결과를 얻었다. 1) Gammacoat $Digoxin^{(R)}$ kit로 측정시 27명의 만성 신부전 환자중 12명에서 신생아의 경우는 27명 전원에서 측정 하한치 이상의 DLI가 검출된 반면, Amerlex Digoxin $RIA^{(R)}$ kit로는 1명을 제외한 양 군의 전원에서 DLI가 관찰되지 않았다. 만성 신부전 환자에서 Gammacoat $Digoxin^{(R)}$ kit로 측정된 DLI와 혈청 BUN/Creatinine 값 사이에는 유의한 상관 관계가 없었다. 2) 만성 신부전 환자 및 신생아의 pooled sera에 가한 digoxin의 수거율은 각각 49%, 40%였다. 3) 만선 신부전 환자 및 신생아의 pooled sera에서 측정되는 DLI의 희석 curve는 정상 희석 curve와 다르다고 할 수 없었다. 4) 만성 신부전 환자의 pooled sera에서 측정되는 DLI의 16%, 그리고 신생아의 pooled sera 에서 측정되는 DLI의 20%가 trypsin에 sensitive하였다. 5) 만성 신부전 환자의 pooled sera에서 측정되는 DLI의 56%가, 그리고 신생아의 pooled sera에서 측정되는 DLI의 경우는 전체의 20%미만이 methylene chloride로 추출되었다. 이상에서 만성 신부전 환자 및 신생아의 혈청에서는 방사면역 kit의 증류에 따라 DLI가 검출되며 그 실체를 알기 위해서는 더욱 연구가 필요하다고 할 수 있었다.