• Journal of Radiation Protection and Research
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• v.34 no.2
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• pp.55-64
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• 2009

In a pressurized heavy water reactor (PHWR), radiation workers who have access to radiation controlled areas submit their urine samples to health physicists periodically; internal radiation exposure is evaluated by the monitoring of these urine samples. Internal radiation exposure at PHWRs accounts for approximately 20 $\sim$ 40% of total radiation exposure; most internal radiation exposure is attributed to tritium. Carbon-14 is not a dominant nuclide in the radiation exposure of workers, but it is one potential nuclide to be necessarily monitored. Carbon-14 is a low energy beta emitter and passes relatively easily into the body of workers by inhalation because its dominant chemical form is radioactive carbon dioxide ($^{14}CO_2$). Most inhaled carbon-14 is rapidly exhaled from the worker's body, but a small amount of carbon-14 remains inside the body and is excreted by urine. In this study, a method for dual analysis of tritium and carbon-14 in urine samples of workers at nuclear power plants is developed and a method for internal dose assessment using its excretion rate result is established. As a result of the developed dual analysis of tritium and carbon-14 in urine samples of radiation workers who entered the high radiation field area at a PHWR, it was found that internal exposure to carbon-14 is unlikely to occur. In addition, through the urine counting results of radiation workers who participated in the open process of steam generators, it was found that the likelihood of internal exposure to either tritium or carbon-14 is extremely low at pressurized water reactors (PWRs).

• Journal of Radiation Protection and Research
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• v.8 no.2
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• pp.8-14
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• 1983

The doses to Korean adult by a single and chronic intake of tritiated water are determined using a three compartment model, which describes the retention of tritium radionuclide in body water and in bound organic form in the body. The results show that the total dose of a single intake, using retention half-time for the three-compartment of 9, 30, and 450 days, is 17.64 mrads ($176.4{\mu}Gy$) per 1mCi/kg ($3.7{\times}10^7Bq/kg$) intake, 97% of which is due to tritium in body water and 3% to bound tritium in tissue. In the chronic intake of 1mCi/day($3.7{\times}10^7Bq/day$) tritiated water, the total dose is 85.5 mrad/day(0.855mGy/day). Furthermore, in this study (MPC) a and (MPC)w values of tritium for Korean man are calculated by using the modified formula originated from ICRP Publication-2. From the results, we found that the (MPC) a, w values of ICRP underestimated approximately 50%, the (MPC)a, w values of Korean man must be elevated as high as approximately 50% than that of ICRP.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.324-332
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• 2018

BACKGROUND: Insects are ectothermic organisms in terrestrial ecosystems and play various roles such as controlling plant biomass and maintaining species diversity. Because insects are ectothermic, their physiological responses are very sensitive to environmental temperature which determines survival and distribution of insect population and that affects climate change. This study aimed to identification of genes contributing to fitness under high temperature. METHODS AND RESULTS: To identify genes contributing to fitness under high temperature, the transcriptomes of fat body in Plutella xyostella larva have been analyzed via next generation sequencing. From the fat body transcriptomes, structure-related proteins, heat shock proteins, antioxidant enzymes and detoxification proteins were identified. Genes encoding proteins such as structural proteins (cuticular proteins, chitin synthase and actin), stress-related protein (cytochrome P450), heat shock protein and antioxidant enzyme (catalase) were up-regulated at high temperature. In contrast expression of glutathione S transferase was down-regulated. CONCLUSION: Identifications of temperature-specific up- or down-regulated genes can be useful for detecting temperature adaptation and understanding physiological responses in insect pests.

• Journal of Radiation Protection and Research
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• v.47 no.3
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• pp.152-157
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• 2022

Background: The hemi-body electron beam irradiation (HBIe^-) technique has been proposed for the treatment of mycosis fungoides. It spares healthy skin using an electron shield. However, shielding electrons is complicated owing to electron scattering effects. In this study, we developed a thimble-like head bolus shield that surrounds the patient's entire head to prevent irradiation of the head during HBIe^-. Materials and Methods: The feasibility of a thimble-like head bolus shield was evaluated using a simplified Geant4 Monte Carlo (MC) simulation. Subsequently, the head bolus was manufactured using a three-dimensional (3D) printed mold and Ecoflex 00-30 silicone. The fabricated head bolus was experimentally validated by measuring the dose to the Rando phantom using a metal-oxide-semiconductor field-effect transistor (MOSFET) detector with clinical configuration of HBIe^-. Results and Discussion: The thimble-like head bolus reduced the electron fluence by 2% compared with that without a shield in the MC simulations. In addition, an improvement in fluence degradation outside the head shield was observed. In the experimental validation using the inhouse-developed bolus shield, this head bolus reduced the electron dose to approximately 2.5% of the prescribed dose. Conclusion: A thimble-like head bolus shield for the HBIe^- technique was developed and validated in this study. This bolus effectively spares healthy skin without underdosage in the region of the target skin in HBIe^-.

• Journal of Radiation Protection and Research
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• v.48 no.3
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• pp.131-143
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• 2023

Background: This study examined the detection limit of thyroid screening monitoring conducted at the time of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 using a Monte Carlo simulation. Materials and Methods: We calculated the detection limit of a NaI(Tl) survey meter to measure ¹³¹I accumulation in the thyroid gland of children. Mathematical phantoms of 1- and 5-year-old children were developed in the simulation of the Particle and Heavy Ion Transport code System code. Contamination of the body surface with eight radionuclides found after the FDNPP accident was assumed to have been deposited on the neck and shoulder area. Results and Discussion: The detection limit was calculated as a function of ambient dose rate. In the case of 40 Bq/cm² contamination on the body surface of the neck, the present simulations showed that residual thyroid radioactivity corresponding to thyroid dose of 100 mSv can be detected within 21 days after intake at the ambient dose rate of 0.2 µSv/hr and within 11 days in the case of 2.0 µSv/hr. When a time constant of 10 seconds was used at the dose rate of 0.2 µSv/hr, the estimated survey meter output error was 5%. Evaluation of the effect of individual differences in the location of the thyroid gland confirmed that the measured value would decrease by approximately 6% for a height difference of ±1 cm and increase by approximately 65% for a depth of 1 cm. Conclusion: In the event of a nuclear disaster, simple measurements carried out using a NaI(Tl) scintillation survey meter remain effective for assessing ¹³¹I intake. However, it should be noted that the presence of short-half-life radioactive materials on the body surface affects the detection limit.

• Journal of the Korean Chemical Society
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• v.46 no.5
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• pp.444-456
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• 2002

To protect the occurrence of the oxidation of car body, we developed antioxidizing device made with sacrificial anode. Because car body is made of iron and iron-alloy and oxidation potential of Mg, Al and Zn is higher than that of iron, sacrificial anodes were made with Mg, Al and Zn. Accordingly, Mg, Al and Zn are better oxidizing than car body, iron and iron-alloy can be protected from oxidizing. We have made an antioxidizing device and evaluated their anti-corrosive effect for iron piece in the solution of hydrochloric, nitric and sulfuric acid using balance, SEM and XPS. When iron pieces were connected with antioxidizing device of car body, weight loss by oxidation was remarkably reduced and surface corrosion of iron piece was protected. It was shown that the surface of iron pieces which is not con-nected to the device was changed to iron(Ⅲ) oxide, Fe$_2$O$_3$. Therefore, if this device is attached to car body, corrosion and oxidation of car body will be reduced, considerably.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1349-1354
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• 1999

This study was carried out to investigate the protective effect of Korean red ginseng water extract (KRG WE) on clinical chemical parameters in male guinea pigs acutely exposed to 2,3,7,8 tetrachlorodibenzo p dioxin(TCDD). Forty male guinea pigs(200 $\pm$20g) were divided into 4 groups. Normal controls(group 1) received vehicle and saline; group 2(single TCDD treated) received TCDD(5 g/kg, single dose) intraperitoneally; group 3 received KRG WE(200mg/kg, i.p.) for 2 weeks from 1 week before TCDD exposure; group 4 received KRG WE for 1 week since the day of TCDD exposure. Increase in body weight was retarded greatly by TCDD exposure. Body weight of animals in group 2 was significantly decreased starting 2 days after TCDD exposure. However, body weight of animals in group 3 increased throughout the experimental period, although the increasing rate was slower than that of group 1. Decrease in body weight was not observed during the experimental period in group 4. Increases in blood glucose, amylase, lipase, total cholesterol, triglyceride, GOT, GPT, and LDH levels by TCDD intoxication were significantly attenuated by the KRG WE treatment(p<0.05). These results provide a strong evidence that Korean red ginseng might be a useful protective agent against TCDD, an endocrine disruptor.

• Fashion & Textile Research Journal
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• v.16 no.3
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• pp.434-445
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• 2014

The meaning of this research is to make recognition for necessity of ergonomic fashion design research. And the purpose is to provide the guidelines for ergonomic fashion product development. For this, literature research and analysis of empirical illustration of product design indicating ergonomics characteristic are implemented. Among the body-conscious active sportswear, cycle wear, swim suit, and skin scuba wet suit were selected and analyzed. Then they were explained according to the ergonomics characteristics arranged previously. Lastly, the features of ergonomic fashion design were arranged by composition elements of the clothing such as pattern, sewing, material and detail. The characteristics of ergonomic design derived from literature and advanced researches are efficiency, usability, functionality and safety. Through research and analysis, the characteristics of ergonomic fashion design are as followings. In pattern, it is related to the 3D structure division pattern, the reduction pattern design, the closing & opening part design for easy detachment, the receipt and the changeable design. In sewing, it is related to the use of latest sewing techniques and the finish using silicon or rubber band. In material, it is related to the use of high performance fabrics and the proper arrangement of these. In detail, it is related to the convenient detail, the storage detail, the adjustable detail, and the body protection detail.

• Journal of Life Science
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• v.11 no.2
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• pp.87-91
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• 2001

We conducted this study to analyze the effectiveness of a treatment called 12-week therapeutic recreation dance movement (TRDM) to elderly people in terms of health care and recovery. Forty two elderly people were participated in this study and divided into two groups with healthy (twelve) and unhealthy (thirty). After TRDM treatment, the muscular power was increased in both groups without statistical significance within and between groups. The flexibility, agility and balance were slightly increased in both groups. Although the elevation of muscular endurance was not significant between groups, it was statistically meaningful within groups. The results of body composition comparison did not reveal meaningful difference within and between groups. However, the amount of fat in serum and fat distribution percentages ware decreased in both groups. Both group appeared to be increased muscle mass. The level of body water was decreased in healthy group and increased in unhealthy group. Unhealthy group appeared to be decreased level of T-C, TG and LDL-C. In contrast, the unhealthy group revealed the increased level of HDL-C. These results demonstrate the effect of TRDM to elderly people. This effectiveness can be adapted for the protection and treatment of geriatics-related adult diseases such as diabetes, hypertension and hyperlipidemia.

• Journal of the Korean institute of surface engineering
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• v.27 no.4
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• pp.207-214
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• 1994

In consideration of global environmental protection and fuel saving, aluminum alloy sheets for auto body panels such as hood, fender etc., are expected one of the most promising materials for weight saving of cars. The chemical conversion coating is required to prevent the filiform corrosion occurring on painted aluminum. However the conventional process for the composited material mixed with aluminum and steel is complexs; aluminum part is chromated and assembled to the body, and then the steel body undergoes Zn phosphating. In order to overcome the low productivity due to the complex process and the environmental problem with a conventional process, a simultaneous zinc phosphating process for alsuminum and steel in an assembled condition is demanded. Newly developed phosphate solution has been investigated to characterize the phosphating behavior under various conditions. The optimum conditions of the phosphating solution for the application of the paint treatment derived as follows : about 0.3 for the ratio of Zn to $PO_4$, , 200~500 ppm for the concentration of fluoride ion, and 2.5~4.0 for pH. The concentration of dissolved aluminum ion must be kept below 2--ppm and suitable accelerator is found to be a mixture of 1g/$\ell$ $NO_2\;^-$, and 6g/$\ell$ $NO_3\;^-$.