• Journal of Radiation Protection and Research
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• v.14 no.1
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• pp.75-83
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• 1989

• Journal of Environmental Science International
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• v.20 no.12
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• pp.1599-1605
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• 2011

To evaluate heat environment surrounding plants diurnal change of leaf temperature in the broad-leaved deciduous and evergreen trees was measured with microclimatic environmental factors including global solar radiation, and upward and downward long wave radiation. Maximum daily solar radiation was 961.2 and 976.3 w/$m^2$ in August 9 and 23, respectively. Upward long wave radiation was slightly higher than downward long wave radiation, showing 404.2 w/$m^2$ in August 9 and 394.5 w/$m^2$ in August 23. In addition, daily maximum vapor pressure deficit was 5.42 and 6.84 kPa in August 9 and 23, respectively, indicating high evaporative demand. Quercus glauca and Acer mono was differently responded to changing light regimes. On August 9, leaf temperature at the top-positioned leaves of Acer plants was higher than air temperature as well as those of Quercus plants in the morning. This indicates that stomata in Acer plants were closed by heat stress or water stress in the morning, while Quercus plant maintained active transpiration by opening stomata. These results indicated that improved light regimes such as gap opening in the closed forest may not always affect positively in the physiology of understory plants.

• Journal of Radiation Protection and Research
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• v.13 no.2
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• pp.41-51
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• 1988

In order to develop a food-chain computer code suitable to the environmental conditions of Korea, the FOOD III code was partially modified. The excution results for Korean male-adult were compared to those from the Canadian version of FOOD III to deduce a more realistic approach in dose assessment. The amounts of Mn-54, Co-58, Co-60, I-131 and I-132 released from Kori unit 1 in1984 were used as the source terms for the sample calculation. The maximum atmospheric dispersion factor(X/Q) value on the site boundary was applied. Through the code modification, organ doses decreased by about $20{\sim}70%$ and the effective committed dose equivalent by about 40% to be $7.935{\times}10^{-6}Sv/y$ which is 0.16% of the ICRP limit, $5{\times}10^{-3}Sv/y$.

• Atmosphere
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• v.21 no.2
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• pp.151-162
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• 2011

One-layer solar radiation(GWNU; Gangneung-Wonju National University) model is developed in order to resolve the lack of vertical observations and fast calculation with high resolution. GWNU model is based on IQBAL(Iqbal, 1983) and NREL(National Renewable Energy Laboratory) methods and corrected by precise multi-layer LBL(Line-by-line) model. Input data were used 42 atmospheric profiles from Garand et al.(2001) for calculation of global radiation by the Multi-layer and one-layer solar radiation models. GWNU model has error of about -0.10% compared with LBL model while IQBAL and NREL models have errors of about -3.92 and -2.57%, respectively. Global solar radiation was calculated by corrected GWNU solar model with satellites(MODIS, OMI and MTSAT-1R), RDPS model prediction data in Korea peninsula in 2009, and the results were compared to surface solar radiation observed by 22 KMA solar sites. All models have correlation($R^2$) of 0.91 with the observed hourly solar radiation, and root mean square errors of IQBAL, NREL and GWNU models are 69.16, 69.74 and $67.53W/m^2$, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2118-2123
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• 2010

Korean individual occupational exposure control is focused on the retrospective service to the over-exposed person by the reading of personal dosimeter. Since the radiophamaceuticals using in the nuclear medicine department are uncontained radiation sources, the potential exposure at working environment is very high. Moreover, a patient remains radioactive for hours or even days after the administration of a radiopharmaceutical for diagnosis or treatment. Thus, the proper working environmental exposure control must be established and executed to protect not only the affiliated employees, but also guardians accompanying patients and temporarily visiting public from the exposure by the patients. Japanese radiation protection law regulates working environmental radiation exposure by regularly measuring and filing the environmental dose for years. This study was aimed at measuring working environmental radiation dose in the nuclear medicine department of an university hospital located in Daejeon, Korea. We measured the accumulation radiation dose in air at 8 locations in the nuclear medicine department by using the same method as in Japan with glass dosimeters. The highest dose rate, 0.23 mSv per month, was measured at the waiting room, and the second one is at reception desk. Even though the doses were lower than the Korean constraint dose rate (0.3 mSv/week) at the boundary of the radiation controlled area, it was over the dose limit of public (1 mSv/y) and environment (0.25 mSv/y). Conclusionally, it was found that the new or additional procedure was necessary to less the exposure dose to the receptionist and guardians by the environmental radiation dose in the nuclear medicine department.

• Economic and Environmental Geology
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• v.32 no.3
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• pp.273-280
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• 1999

In order to protect inhabitans' health and to collect data for prediction of the effcts from accidental emission of rasioactive materials from nuclear power plant, exposed dose rate be monitored within the limit dose rate. This research was carried out to investigate the accumulation of environmental radioactivity around Younggwang Nuclear Power Plant, and to infer and in infer and assay the additional exposed dose rate of inhabitants in Younggwang site from the operation of nuclear plant operation. External radiation dose rate, radiation environmental samples, and exposed dose rate of inhabitants in Younggwang site were investigated for estimaing environment activity in the vicinity of the nuclear power plant area. For the external radiation dose rate, the result showed that range of normal variation was found and any artificial radioisotope was not deteted in the analysis of environmental samples. Exposed dose rate of inhabitants was lower than 0.4% of the limit value of ICRP and it may be concluded that there was no effect on inhabitants and environment from the operation of nuclear power plant.

• BMB Reports
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• v.36 no.1
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• pp.144-148
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• 2003

During the past 2 decades, radiation tumorigenesis researchers have focused on cellular and molecular mechanisms. We reviewed some of these research fields, since they may specifically relate to the induction of cancer by ionizing radiation. First, radiation-mediated mutation was discussed. Then the initiating event in radiation carcinogenesis, as well as other genetic events that may by involved, is discussed in terms of the possible role of the activation of genes and the loss of cell-cycle checkpoints.

• Nuclear Engineering and Technology
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• v.48 no.3
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• pp.608-612
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• 2016

D-(+)-glucose (Glc) was added to the original Fricke polyvinyl alcohol-glutaraldehyde-xylenol orange (FPGX) hydrogel dosimeter system to make a more stable FPGX hydrogel three-dimensional dosimeter in this paper. Polyvinyl alcohol was used as a substrate, which was combined with Fricke solution. Various concentrations of Glc were tested with linear relevant fitting for optimal hydrogel production conditions. The effects of various formulations on the stability and sensitivity of dosimeters were evaluated. The results indicated that D-(+)-Glc, as a free radical scavenger, had a great effect on stabilizing the dose response related to absorbency and reducing the auto-oxidization of ferrous ions. A careful doping with Glc could slow down the color change of the dosimeter before and after radiation without any effect on the sensitivity of the dosimeter.

• Journal of the Korea Convergence Society
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• v.9 no.5
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• pp.85-90
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• 2018

Fundamental data on the safety status is necessary to develop and operate the additional policies related to the radiation safety, however, few studies have been conducted to investigate the status quantitatively. In this study, out of the areas related to radiation safety, the status of the radiation worker, ambient radiation and the environmental radiation were examined in the quantitative aspect using diverse statistical methods. In the results of that, following information were obtained. First, out of the radiation workers engaged in 9 businesses as of end of 2014, the business having highest exposure dose is NDT showing significantly high than other businesses. Second, the average difference of the exposure doses in radiation workers in 9 businesses in 2014 compared to that in 2010 was not statistically significant at significance level of 5% (p=0.221). Third, the average of the environmental radiation in Gyeonggi-do was high than the Jeollabuk-do. The results of this study are anticipated to assist to utilize the basic data for the workers on radiational works, daily living radiation, and the safety control related to the environmental radiation, and to establish the policy of radiation protection in the future.

• Journal of Photoscience
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• v.9 no.2
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• pp.436-438
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• 2002

Since solar radiation contains wavelength essential for photosynthesis accompanying with near-UV light, UV-B effects on biological parameters and acclimation mechanisms are influenced by photosynthetically active radiation (PAR). Therefore, to elucidate near-UV shielding mechanism in higher plants, we cultivated cauliflower under usual solar radiation and increased UV-B from fluorescent lamps, two- or three-fold excess over continuously estimated UV-B dose in PAR during daytime, using computer regulated systems. Increased UV-B radiation had little effect on growth expressed as fresh weigh and leaf area. Water soluble low molecular weight compounds showing absorption in near UV region were enhanced according to the irradiated UV-B dose. One of compounds in cauliflower leaves was identified as chlorogenic acid. This was found to have no near-UV photosenSitizerable activity and is known to have an ability to scavenge a wide species of active oxygen. Another pro-oxidant compound that generates superoxide anion radical under near-UV irradiation was not induced by increased UV-B during cultivation, and identified as lumazine, a degradation product from folic acid.