• Nuclear Engineering and Technology
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• 제42권4호
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• pp.468-473
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• 2010

We confirmed that the dismantling of two research reactors with thermal power of $2MW_{th}$ and $100kW_{th}$, respectively, reveals no significant difference between the radiation levels of the research reactor site and the surrounding environment far away from it, from the radiation level aspect. Radiation dose and radioactivity were measured at monitoring points around the research reactor site of the Korea Atomic Energy Research Institute (KAERI) in Seoul and comparison points 0.5 km to 3.3 km from the site. To grasp trends in the radiation levels during dismantling from the end of 2002 to the end of 2007, the gamma radiation dose rate, the accumulated dose, and the radioactivity of the strontium, tritium, and gamma isotopes were statistically treated and estimated. The averages of these items between the two groups, the research reactor site and comparison points, were assessed by applying a T-test with a significance level of 0.05. P-values found by using the T-test were from 0.12 to 0.83 where the values were much higher than the significance level. As a result, no difference was observed between the radiation levels at the research reactor site and at the comparison points by this T-test. This study showed that dismantling activity of the Korea Research Reactor of the Seoul site did not expose the public or the environment to harmful levels of radiation.

• 방사성폐기물학회지
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• 제21권4호
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• pp.543-558
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• 2023

Currently, Japan is undertaking a nationwide project to measure and map radioactive contamination around Fukushima, as part of the efforts to restore normalcy following the nuclear accident. The Japan Atomic Energy Agency (JAEA) manages the Fukushima Environmental Safety Center, located approximately 20 km north of the Fukushima Daiichi nuclear power plant in Minamisōma City, Fukushima Prefecture. In collaboration with the JAEA, this study involved conducting comparison experiments and analyses with radiation detectors in high radiation environments, a challenging task in Korean environments. Environmental radiation surveys were conducted using three types of detectors: CZT, NaI(Tl), and LaBr₃(Ce), across two contaminated areas. Dose rate values were converted using dose rate conversion factors for each detector type, and dose rate maps were subsequently created and compared. The detectors yielded similar results, demonstrating their feasibility and reliability in high radiation environments. The findings of this study are expected to be a crucial reference for enhancing the verification and supplementation of procedures and methods in future radiation measurements and mobile surveys in high-radiation environments, using these three types of radiation instruments.

• 방사선산업학회지
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• 제18권1호
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• pp.1-7
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• 2024

The International Commission on Radiological Protection (ICRP) lowered the annual equivalent dose limit of lens of the eye for radiation workers from 150 to 20 mSv in April 2011. This trend of lowering the equivalent dose limit for radiation workers has been observed worldwide, including international organizations such as the International Atomic Energy Agency (IAEA), International Organization for Standardization (ISO) and the European Commission (EC). In 2016, the Nuclear Safety and Security Commission of South Korea published research results that included a proposal for lowering the equivalent dose limit of lens of the eye for radiation workers in line with the ICRP recommendation. However, as of now, South Korea's Nuclear Safety Act and related regulations still specify an annual equivalent dose limit of lens of the eye as 150 mSv for radiation workers. The IAEA and ISO have issued guidelines regarding radiation protection for lens of the eye and recommended a dose level for the lens of the eye at 5 or 6 mSv per year for periodic monitoring of the equivalent dose for the lens of the eye.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.200.1-200.1
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• 2010

Solar energy is one of the most promising energy resources in the future. For the application and dissemination of solar energy technologies in various fields, reliable data sets of solar irradiation are needed for engineers, researchers, businessmen, and policy makers. Global horizontal solar radiation is needed for the use of flat plate collector, solar domestic hot water system, photovoltaic devices and passive systems like green house. In many countries, solar radiation data accumulated for more then 40 or 50 years and typical weather data are published with average of more then 30 years. In Korea, those global total radiations are measured for about 30 years. With the connections of computer network, measured data could be transmitted to the central control system at key station through Ethernet lines. The data acquisition systems are connected to be automatically controlled by the monitoring network. Global horizontal solar radiation data 16 locations were measured and averaged from 1982 to 2008.

• 제어로봇시스템학회논문지
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• 제10권3호
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• pp.249-254
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• 2004

The radiation dosage of nuclear fuel handling machine of PHWR type NPP during normal operation is measured using semiconductor detectors. In order to predict and mitigate the damage of main components in fuel handling machine, caused by high irradiation, the radiation dosage exerted to the components by neutron and gamma ray is measured independently during one time of the fuel exchange, which is used far estimating the radiation dosage for one year. This result can guarantee the safety and economical efficiency for determining the replacement time of the high cost main components in fuel handling machine.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2009년도 춘계학술대회
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• pp.409-414
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• 2009

I have not seen each of the existing technology, RFID/USN technology combined with the wireless communication channel for the state of nuclear safety in real-time remote monitoring and operation system technology CARE existing radioactive accident information collected by the nuclear power and nuclear power status, 10-20 second intervals to monitor the safety network (SIDS), and nuclear power plants located on the site within 40 ㎞ radius around the 13~15 of the wind speed from the automatic weather network weather information such as rainfall and temperature every 10 minutes to collect as automatic weather network (REMDAS), Evaluation of atmospheric radiation and radiation of the bomb radiation impact assessment system to calculate the goodness (FADAS) and thicken the radiation-related information consists of real-time web technology to collect, the last robot on behalf of the human will to manage the nuclear power plant accident of the technology to prevent the concrete from the following narrative about to have.

• Journal of Radiation Protection and Research
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• 제12권1호
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• pp.54-60
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• 1987

The quasi-exposure rate and the quasi-effective energy of the natural radiation in the field at 47 monitoring points around nuclear power plants have been studied with the pair filter thermoluminescence dosimeter system. The results of the six years observation showed that the relationship between the quasi-exposure rate $X_q$, and quasi-effective energy $E_q$ can be represented as a hyperbolic function: $X_q=A+C/(E_q-B)$, where the constants A and B correspond to the quasi-exposure rate of cosmic-rays and the minimum quasi-effective energy of natural radiation, respectively. Furthermore, the constant A is in close agreement with the values obtained by using ionization chambers and scintillation detectors. The constant B is approximately 0.68 MeV, closely corresponding to the mean energy of the photons emitted from natural uranium.

• 방사선산업학회지
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• 제18권2호
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• pp.141-145
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• 2024

In Publication No. 66 of the International Commission on Radiological Protection, an activity median aerodynamic diameter (AMAD) of 5 ㎛ is considered in internal exposure dose assessment owing to inhalation of radionuclides in a workplace. However, analysis of aerosols generated during dismantling experiments, such as in the oxy-cutting of a reactor vessel conducted in Korea, revealed that the radioactive aerosols have AMAD ranging from 0.024 to 0.064 ㎛. Such extremely fine aerosols can induce internal exposure if inhaled. In particular, alpha radionuclides in aerosols can lead to significantly higher levels of radiation exposure than beta and gamma radionuclides, thus highlighting the need to establish appropriate internal exposure radiation protection programs and monitoring systems that specifically address alpha radionuclides when decommissioning nuclear power plants in Korea.

• 한국의학물리학회지:의학물리
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• 제25권2호
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• pp.95-99
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• 2014

병원을 포함해서서 방사선 물질을 사용하는 모든 사업장에서 방사선 물질의 모니터링은 방사선 안전에 가장 중요한 요소의 하나이다. 본 연구는 방사선 모니터링 시스템에 있어서 GEM 검출기의 활용 가능성을 알아보기 위한 선행 연구로서, GEM 검출기를 제작하고 CdTe 검출기와의 상대적 효율을 구한 결과, 베타와 감마선에 대한 평균 상대 효율이 각각 72%와 4%로서 매우 우수한 성능을 나타냄을 보였다.

• Journal of Astronomy and Space Sciences
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• 제30권2호
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• pp.107-112
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• 2013

Tissue equivalent proportional counter (TEPC) can measure the Linear Energy Transfer (LET) spectrum and calculate the equivalent dose for the complicated radiation field in space. In this paper, we developed and characterized a TEPC for radiation monitoring in International Space Station (ISS). The prototype TEPC which can simulate a 2 ${\mu}m$ of the site diameter for micro-dosimetry has been tested with a standard alpha source ($^{241}Am$, 5.5 MeV). Also, the calibration of the TEPC was performed by the $^{252}Cf$ neutron standard source in Korea Research Institute of Standards and Science (KRISS). The determined calibration factor was $k_f=3.59{\times}10^{-7}$ mSv/R.