• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.562-571
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• 2003

A series of factors such as sampling, pretreatment measurement, volume estimation which induces uncertainty of the calculated radioactivity in liquid effluent released from a nuclear power plant were analyzed. It is innately impossible to estimate exact error of the calculated radioactivity, since most of the input parameters are determined by a single measurement and true value of the released radioactivity cannot be known. In this paper, a systematic model to calculate uncertainty of the released liquid radioactivity was developed based upon the guidance report published by the ISO in 1993, and the model was applied to a set of hypothetical batch release conditions. As a result, the Priority of each input parameter was turned out to be (1) wastewater volume, (2) sample volume, and (3) measured radioactivity of the sample. In addition, probability distribution of the released radioactivity was simulated by Monte Carlo method combining the probability distribution of each input parameter It was shown that the radioactivity released to the environment, which has been reported as a single value, has a certain form of probability distribution.

• Journal of Radiation Protection and Research
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• v.34 no.3
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• pp.121-128
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• 2009

During the maintenance period at Korean nuclear power plants, internal exposure of radiation workers occurred by the inhalation of $^{131}I$ released to the reactor building when primary system was opened. The internal radioactivity of radiation workers contaminated by $^{131}I$ was immediately measured using a whole body counter and the whole body counting was performed again after a few days. In this study, the intake estimated from the record history of entrance to radiation control areas and the measurement results of air sampling for $^{131}I$ in those areas, were compared with that from the results of whole body counting. As a result, it was concluded that the intake estimation using whole body counting and air sampling showed similar results.

• 대한방사선방어학회:학술대회논문집
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• 2011.04a
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• pp.168-169
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• 2011

• Journal of Radiation Protection and Research
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• v.24 no.3
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• pp.171-184
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• 1999

In this paper, using statistical theory the basic concepts and the formulars of lower limit of detection were deasribed. Assuming that risks of 5% are acceptable (95% confidence level), lower limits of detection were calculated on the measuring apparatus for alpha, beta and gamma nuclides. Also, on the basis concepts of lower limit of detection, the MDA values were calculated for the radionuclides detected easily in the environment. These results make it possible to evaluate confidence limits on the radioanalytical results in the environmental sample.

• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.188-189
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• 2009

• Journal of Korean Society of Environmental Engineers
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• v.38 no.1
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• pp.42-46
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• 2016

The radioactive iodine ($^{131}I$) presents in the environment through the excrete process of nuclear medicine patients. In the detecting of low level of $^{131}I$ in the public water, the counting uncertainty has an effect on the accuracy and reliability of detecting $^{131}I$ radioactivity concentration. In this study, the contribution of sample amount, radioactivity concentration and counting time to the uncertainty was investigated in the case of public water sample. Sampling points are public water and the effluents of a sewage treatment plant at Sapkyocheon stream, Geumgang river. In each point, 1, 10 and 20 L of liquid samples were collected and prepared by evaporation method. The HPGe (High Purity Germanium) detector was used to detect and analyze emitted gamma-ray from samples. The radioactivity concentration of $^{131}I$ were in the range of 0.03 to 1.8 Bq/L. The comparison of the counting uncertainty of the sample amount, 1 L sample is unable to verify the existence of the $^{131}I$ under 0.5 Bq/L radioactivity concentration. Considering the short half-life of $^{131}I$ (8.03 days), a method for measuring 1 L sample was used. However comparing the detecting and preparing time of 1, 10 L respectively, detecting 10 L sample would be an appropriate method to distinguish $^{131}I$ concentration in the public water.

• Journal of Radiation Protection and Research
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• v.26 no.4
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• pp.393-398
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• 2001

The non-combustible RI wastes disposed of in hospital every year emit ${\gamma}$-ray or ${\beta}$-ray but their activities are very low to the extent of background. Development of more simple methods is needed because the conventional detection methods are so ineffective and complex. In this study, to solve this problem, detection method using efficiency curve for ${\gamma}$-ray emitting radioactive wastes measurement is proposed and experimental detection efficiency equation is also determined through HPGe's standard specimen measurement. For ${\beta}$-emitting radioisotopes detection, new measurement method using detection efficiency estimated by Monte Carlo simulation and SBD measurements is also proposed. According to the results of this paper, the unknown activity of low-level radioactive wastes without LSC requiring the preparation of standard sample and measurement for standard source detection efficiency could be determined efficiently and simply about ${\pm}17%$ in errors by using the theoretical detection efficiency and the SBD measurement result.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.11
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• pp.1519-1527
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• 2020

AGeneral radiation measuring devices have been developed in the form of spatial dose rate detection devices that measure dose rates to radioactive contaminant and 2D or 3D imaging devices for radioactive contamination information. Each of these radiation detection techniques has advantages. The advantages of both detection devices are necessary to minimize personal injury and rapid decontamination in the area of a radioactive accident. In this paper, we proposed a technique that can measure the dose rate and direction information about the radioactive pollutant source in real time using a detection sensor, a rotating body, and a directional shield for radioactive pollutant detection. The rotational-based detection device is configured to check the dose rate and direction using the location information of the rotator and measurement value. We proposed a measurement technique for vertical and horizontal directions through multiple holes. It was confirmed that the measurement error for direction information was less than 1% when detected in the horizontal direction.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.06a
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• pp.428-429
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• 2009

• Applied Biological Chemistry
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• v.14 no.1
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• pp.51-57
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• 1971

In order to compare their absorption abilities of carbon dioxide, Hyamine base and phenyl ethylamine were employed in wet combustion experiments. The known content of liver lipid and uniformly mixed palmitic $acid-C^{14}$ were oxidized with sulfuric acid and phosphoric acid. Carbon dioxide produced was trapped by the amines tested through thin tube. The amines absorbed carbon dioxide were mixed with diotal scintillator and counted by liquid scintillation counter. The counting efficiencies and radioactivity recoveries were 50 to 60 % and nearly 100 % for both amines. However, the absorption ability of carbon dioxide by phenyl ethylamine was about two times that of Hyamine base. This technique would not be necessary for the counting of liver lipid of swim, because the efficiencies were not increased and counting accuracies were similar to those of direct counting.