• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.237-241
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• 2013

The gamma energy distributions at the major working places during refueling outage of Korean PWR nuclear power plants were measured. In order to estimate the dose reduction effect of a lead vest, Monte Carlo calculation method was used. For the simulations, the MIRD-V phantom with a lead vest was formed and exposed to the measured radiation field. The average measured gamma energy is lower than that of standard which is generally applied to radiation protection procedures. For the efficient use of a lead vest and achievement of radiation protection purpose, it is necessary to estimate the energy distribution of radiation field at working places.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.3
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• pp.41-48
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• 2014

This paper provides the design of system software for the management of radiation dose that is generated by using computerized tomography(CT). Recently, the radiation leakage incident of Japanese nuclear power plant was in the news internationally and there is a growing interest not only in nuclear power plant but in medical radiation exposure. In spite of the fact that currently safety management of radiation is under control only the workers of the radiation involved, now the exposure management of patients have been required. As surgery and inspections using the radiation have increased, this medical radiation exposure is increasing too. But it is a real situation that medical institutions don't know the level of radiation exposure applied to the patient. Therefore, a system for managing the radiation exposure of a patient from the medical institution is required. This paper proposes a design of a software program that manages the radiation exposure of CT which is a typical imaging tool to use the radiation in the medical institution. By check the amount of radiation dose and set the limit of dose, we would be of help to optimize the medical exposure of the patient.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.243-253
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• 2021

In the dismantling process of a reactor coolant system (RCS) piping, a radiation protection plan should be established to minimize the radiation exposure doses of dismantling workers. Hence, it is necessary to estimate the individual effective dose in the RCS piping dismantling process when decommissioning a nuclear power plant. In this study, the radiation exposure doses of the dismantling workers at different positions was estimated using the MicroShield dose assessment program based on the NUREG/CR-1595 report. The individual effective dose, which is the sum of the effective dose to each tissue considering the working time, was used to estimate the radiation exposure dose. The estimations of the simulation results for all RCS piping dismantling tasks satisfied the dose limits prescribed by the ICRP-60 report. In dismantling the RCS piping of the Kori-1 or Wolsong-1 units in South Korea, the estimation and reduction method for the radiation exposure dose, and the simulated results of this study can be used to implement the radiation safety for optimal dismantling by providing information on the radiation exposure doses of the dismantling workers.

• Journal of Power Electronics
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• v.10 no.4
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• pp.405-411
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• 2010

This paper proposes a novel tracking algorithm considering radiation to improve the power of a photovoltaic (PV) tracking system. The sensor method used in a conventional PV plant is unable to track the sun's exact position when the intensity of solar radiation is low. It also has the problem of malfunctions in the tracking system due to rapid changes in the climate. The program method generates power loss due to unnecessary operation of the tracking system because it is not adapted to various weather conditions. This tracking system does not increase the power above that of a power of tracking system fixed at a specific position due to these problems. To reduce the power loss, this paper proposes a novel control algorithm for a tracking system and proves the validity of the proposed control algorithm through a comparison with the conventional PV tracking method.

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.333-338
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• 2003

Cytogenetic and hematological analysis was performed in bovine peripheral blood from the regions around Wolsong nuclear power plant and control area. The frequency of micronuclei (MN) in peripheral blood lymphocytes from cattle was used as a biomarker of radiobiological effects resulting from exposure to environmental radiation. An estimated dare of radiation was calculated by a best fitting linear-quadratic model based on the radiation-induced MN formation from the bovine lymphocytes exposed in vitro to radiation over the range from 0 Gy to 4 Gy. MN rates in lymphocytes of cattle from Wolsong nuclear power plant and control area were 9.87/1,000 and 9.60/1,000, respectively. There were no significant differences in MN frequencies and hematological values in cattle between Wolsong and control area. The study indicates that the MN assay is a rapid, sensitive and accurate method that can be used to monitor a large population exposed to radiation.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.9
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• pp.556-558
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• 2005

The effect of high irradiation on inspection systems in a nuclear power plant can be severe, especially to electronic components such as control hoards. The effect may lead to a critical malfunction or trouble to a underwater robot for inspection and maintenance of nuclear reactor. However, if information on the total accumulated dose on the sensitive parts of the robot is available, a prediction of robot's behavior in radiation environments becomes possible. To know how much radiation the robot has encountered, a dosimeter to measure the total accumulated dose is necessary. This paper describes the development effort of a dual radiation monitoring system using a SiC diode as a dose-rate meter and a p-type power MOSFET as a dose meter. This attempt using two sensors which detect same radiation improves reliability and stability at high intensity radiation detection in nuclear facilities. It uses the concept of diversity and redundancy.

• Journal of Radiation Protection and Research
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• v.39 no.1
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• pp.14-20
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• 2014

A lot of radiation exposure for radiation workers who are engaged in Nuclear Power Plants, especially PWRs, have been caused during the outage by CRUD, such as $^{58}Co$, $^{60}Co$, in Reactor Coolant System. And therefore we need to know source terms to achieve optimization of protection for the radiation workers from radiation exposure at Nuclear Power Plants efficiently. This study analyzed source terms at domestic NPPs (PWRs) nearby Steam Generator with CZT semiconductor detector using by IN-VIVO method during the outage for the first time in the country. We checked difference for the detected source terms between old and new NPP. It was performed especially to see a change of source terms by water chemistry process as well. There was not any difference by water chemistry process both NPPs. The main source terms are $^{58}Co$ and $^{60}Co$ at all NPPs. $^{59}Fe$ only appears in the new NPP. $^{137}Cs$ and $^{95}Zr$ are shown in the old NPP. The fraction of $^{58}Co/^{60}Co$ in the new NPP is higher than the old NPP for increasing the specific activity of $^{60}Co$.

• Journal of Radiation Protection and Research
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• v.39 no.4
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• pp.187-198
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• 2014

I developed a curriculum reflecting the perspectives of students, science teachers, and professionals in order to carry out standardized, fundamental nuclear power and radiation education in schools. Among elementary, middle, and high schools, 78.4%, 78.6%, and 93.1% respectively exhibited (with high frequency) a need for nuclear power and radiation education. The proposed elementary and middle/high school course titles are "Radiation and Life" and "Nuclear Power and Radiation" respectively. The courses are offered at every grade level and span one semester each year. The duration of each weekly class varies; at the elementary, middle, and high school levels classes meet for 40, 45, and 50 minutes respectively. Thin textbooks containing an abundance of cartoons and photos were requested. The starting points for education were fixed at the sixth grade, second year of middle school, and the first year of high school. It was stipulated that the education be separate from the regular curriculum, and encompass a creative and experimental field study based on the principal and science teachers' needs. Similar trends were observable according to grade levels regarding class hours, textbook format, form of education, and educational necessity. A simulation of the devised curriculum revealed an overall goodness of fit totaling $3.88{\pm}0.60$, $3.89{\pm}0.60$, and $3.66{\pm}0.63$ out of five for elementary, middle school, and high school students respectively, which are scores equivalent to 70 and above (out of 100). The significance of this study is that it is the first to propose a curriculum designed to cultivate value judgment based on understanding nuclear power and radiation. However, the realization of nuclear power and radiation education requires that follow-up measures be taken regarding textbook development, amendments to related laws, and the providing of teaching plans.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1530-1535
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• 2011

Heat radiation of LED luminaires has risen a problem when applied indoor. LEDs can save energy with higher efficacy than other light sources. However, their heat radiation may increase power consumption for air-conditioning. Therefore, this paper carried out a comparative analysis on the amount of heat radiation for MR16, E26 bulb, and down-light which will be replaced to LED luminaires. Heat amount of LED-MR16 and LED-downlight was 48% and 87.5% lower than that of conventional lamps, halogen MR16 and E26 CFL, respectively. Consequently, the heat amount and indoor temperature were proportional to the power consumption of luminaire. Therefore, the use of LED luminaire can reduce the amount of heat radiation as well as power consumption.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.9
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• pp.1248-1252
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• 2014

In this study, we designed a signal processing module using a radiation hardened technology that can be applied to the all measurement sensors inside nuclear power plant containment. Also, for verification that it can be used for high-level radiation environment (Harsh environmental zone inside containment of NPP), we carried out evaluation tests for a designed module using a $Co^{60}$ gamma-ray source up to 12 kGy(Si). And, we had checked radiation hardening level that it has been satisfied up to 12 kGy(Si).