• Journal of radiological science and technology
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• v.26 no.3
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• pp.51-57
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• 2003

Mitigation of fast neutron irradiation damage on reactor vessel and improvement of mechanical integrity are desired for the successful plant life-time extension. In this study, the performance of metallic hydride for this application is reviewed and compared. First, selected prospective metallic hydrides are evaluated by MCNP code and put into the attenuation test using Cf-252 neutron source. Since for the reactor application high moderation and reflection with no absorption are favored, Z factor is introduced for the evaluation. According to the Z value estimation $ZrD_2$ and $TiD_2$ are turned out to be the most favorable fast neutron shielding materials. More thorough evaluation by computer simulation and experimentally, will be followed.

• Korean Journal of Remote Sensing
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• v.34 no.5
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• pp.709-720
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• 2018

In order to optimize the evaluation of biomass in crop monitoring, accurate and timely data of the crop-field are required. Evaluating above-ground biomass helps to monitor crop vitality and to predict yield. Unmanned Aerial Vehicle (UAV) imagery are being assessed for analyzing within field spatial variability for agricultural precision management, because UAV imagery may be acquired quickly during critical periods of rapid crop growth. This study reports on the development of remote sensing techniques for evaluating the biomass of winter crop. Specific objective was to develop statistical models for estimating the dry weight of barley and wheat using a Excess Green index ($E{\times}G$) based Vegetation Fraction (VF) and a Crop Surface Model (CSM) based Plant Height (PH) value. As a result, the multiple linear regression equations consisting of three independent variables (VF, PH, and $VF{\times}PH$) and above-ground dry weight provided good fits with coefficients of determination ($R^2$) ranging from 0.86 to 0.99 with 5 cultivars. In the case of the barley, the coefficient of determination was 0.91 and the root mean squared error of measurement was $102.09g/m^2$. And for the wheat, the coefficient of determination was 0.90 and the root mean squared error of measurement was $110.87g/m^2$. Therefore, it will be possible to evaluate the biomass of winter crop through the UAV image for the crop growth monitoring.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.910-918
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• 2010

In recent years, riparian buffer system has been known as one of the effective best management practices. However, establishment of riparian buffer system in aspect of plant species and its position in the riparian buffer zone has not been investigated due to lack of efficient evaluation method for the analysis of water quality improvement with established riparian buffer system. To solve this problem, the SWAT-REMM prototype was developed by the researchers in Canada. But, SWAT-REMM model can not consider the $NO_3-N$ load into riparian buffer system through subsurface flow. Thus to solved this problem, Fortran code of SWAT-REMM model was modified. This modified SWAT-REMM system was applied to the Bonggok watershed. Three riparian buffer scenarios, 15 m, 10 m, 5 m width for tree and grass, were made to evaluate the effects of riparian buffer system on water quality improvement. Reduction efficiency of T-N by riparian buffer system of 15 m wide was the greatest (6 ~ 37%, depending on subwatershed characteristics) among 3 scenarios. It indicates that the reduction efficiency of T-N load has increasing-tendency, as buffer width increasing. The results obtained from the analysis showed that wide buffer zones are found to be more effective in reducing non-point pollutant than narrow buffer zones in the riparian buffer zone system. Hence, the SWAT-REMM model could be efficiently used for evaluation and design the most effective riparian buffer systems to reduce pollutant loads to the watershed although many limitations still exist in SWAT-REMM model.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.195-202
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• 2010

The evaluation of organic matters and nutrients removal was investigated for the synthetic wastewater and the high strength of dairy wastewater. Two different systems were performed for this research. System A composing of a single RBC with tapered aeration was fed with the synthetic wastewater for 74 days with 173L/day of influent, 200% of internal return and 100% of sludge return for the period 1 and 2. The feed conditions were maintained 346L/day of influent, 50% of internal return and sludge return for the period 3. The dairy wastewater was introduced to evaluate treatment efficiency for system B composing of dual RBCs and tapered aeration tanks for 50 days of experimental run time, in which hydraulic rates were maintained at the constant ratios of 346L/day, 50% of internal return and 50% of sludge return. The spiral string media made of nylon fibre was attached by Bacillus sp. in RBC for both systems. The specific area of string media was $1.4m^2$/m and biomass was maintained at the concentrations of 23g/m. The synthetic wastewater was supplied by 1,800mg/L of glucose, 500mg/L of $NH_4Cl$, and 500mg/L of $KH_2PO_4$ to system A. The dairy wastewater was supplied to system B from dairy production plant. The average influent concentrations were 1,334mg/L of BOD, 2,014mg/L of CODcr, 160mg/L of T-N, and 12mg/L of T-P in system A. The average influent concentrations of parameters were 1,006 mg/L for BOD, 1,875mg/L for $COD_{cr}$, 51.6mg/L for T-N and 8.9mg/L for T-P in system B. Results indicated that removal efficiencies of BOD and $COD_{cr}$ were more than 90% however, the removal efficiency of T-N was 87%, and that of T-P was 82% for system A. Removal efficiencies were 98.5% of BOD, 91.3% of nitrogen and 89% of phosphorus for system B. The removal efficiencies of organic matters, T-N and T-P were higher in system B than in system A. The effluent quality issued by the stringent national legislations for the discharge of the high strength of dairy products wastewater can be improved using sequential RBCsand tapered aeration reactors rather than a single RBC and tapered aeration reactors with Bacillus sp.

• Korean Journal of Community Nutrition
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• v.14 no.3
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• pp.266-276
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• 2009

The purpose of this study was to implement and evaluate the nutrition education program for elementary school children Subjects were 5th graders (n = 142) of an elementary school in Seoul, and 138 children completed four sessions of nutrition education during March-April, 2008. One group pretest-posttest design was used to evaluate the program effectiveness. Anthropometric measurements and measurements on nutrition knowledge, eating attitudes and eating behavior were done before and after education. Data were analyzed using paired t-test, t-test and ${\chi}^2-test$. After completing nutrition education, body mass index (from 19.3 to 18.9), fat mass (from 10.9 kg to 10.1 kg), percent body fat (from 25% to 23.3%) of subjects decreased significantly (p < 0.001). Percentages of overweight or obese children were 24.6% at pretest and decreased to 20.3% at posttest, although it did not reach statistical significance. Total score of nutrition knowledge increased significantly from 11.9 (59.5/100) at pretest to 14.7 (73.5/100) at posttest (p < 0.001). After nutrition education, percentages of correct answers increased significantly in 10 knowledge items out of 20 items. These included items such as desirable weight control, energy requirements for boys, food groups, snack, and function of fat and balanced meals (p < 0.001). Total score of eating attitudes increased significantly from 35.1 to 36.9 (p < 0.001). Attitude of applying nutrition knowledge to daily life (p < 0.001), interest toward nutrition and health (p < 0.001), attitude of moderating food intake (p < 0.01), and attitude toward eating habit and future health (p < 0.05) were significantly different between pretest and posttest. Total score of eating behaviors increased significantly from 46.7 (possible score: 20-60) to 49.5 by nutrition education (p < 0.001). Improvement in eight eating behaviors were noticed after nutrition education. These included eating meals slowly, eat protein foods (p < 0.001), eating breakfast, eating meals regularly, eating meals with diverse foods, having dairy foods, eating foods using plant oils (p < 0.01), and having grains (p < 0.05). Subjects evaluated quite positively in attractiveness of program, understanding of program contents, helpfulness of program in improving nutrition knowledge and meal management. Study results show that the nutrition education program was effective in improving nutrition knowledge, eating attitudes and changing eating behaviors of children. This program can be used in nutrition education of children at school or at public health centers.

• Economic and Environmental Geology
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• v.51 no.2
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• pp.149-166
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• 2018

Many large earthquakes have continuously been reported and resulted in significant human casualties and extensive damages to properties globally. The accident of Fukushima nuclear power plant in Japan was caused by a mega-tsunami, which is a secondary effect associated with the Tohoku large earthquake (M=9.0, 2011. 3. 11.). Most earthquakes occur by reactivation of pre-existing active faults. Therefore, the importance of paleoseismological study have greatly been increased. The Korean peninsula has generally been considered to be a tectonically stable region compared with neighboring countries such as Japan and Taiwan, because it is located on the margin of the Eurasian intra-continental region. However, the recent earthquakes in Gyeongju and Pohang have brought considerable insecurity on earthquake hazard. In particular, this region should be secure against earthquake, because many nuclear facilties and large industrial facilities are located in this area. However, some large earthquakes have been reported in historic documents and also several active faults have been reported in southeast Korea. This study explains the evaluation methods of geological structures on active fault, fault damage zone, the relationship between earthquake and active fault, and respect distance. This study can contribute to selection of safe locations for nuclear facilities and to earthquake hazards and disaster prevention.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.5
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• pp.277-281
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• 2017

Lately rainfall characteristics that it rains a lot in a short space of time often occurs. Because of this meteorological phenomena, the flow rate and concentration of initial rainfall for runoff and combined sewer overflows are changed. In the case of this inlet fluctuation, the flotation method at high surface loading rate is suitable for water quality management. the flotation method is able to meet the removal rate requirements of water public zone in 5 to 10 min which is irelatively short period. For assessment and diagonision of flotation method, A/S ratio is applied until now. But unfortunately, this has some limits for evaluation standard for certification and assessment of technical diagnosis and operation. This is why there is different efficiency in the bubble distribution at the same A/S ratio. The velocity and time of floating is changed by the different bubble distributions. The floating time affects the plant volume because the time factor make size dicision. Therefore the charateristics of bubble distribution and floating time at the same A/S ratio is necessary to apply to evaluation standard for certification and assessment of technical diagnosis and operation. For generalization of the method in certification and assessment, the characteristics of bubble distribution was studied. Until recently, using the optical device and shooting live video, there are some analysis technology of the floating factors. But this kind of technology is influenced by the equipment. with this level of confidence about the results, it is difficult to apply to generalize. According this reasons, this study should be applied on experiment generalization of method about measurement of relation between bubble distribution and floating time.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.5 no.2
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• pp.75-80
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• 2012

Purpose: The purpose of this study is to evaluate the usefulness of ultrasonographic examination for diagnosis and removal of small sized foreign bodies, which invaded extremity but difficulty to find on physical examination and/or plane radiographs. Materials and Methods: Since March, 2009 to February, 2012, we performed preoperatively ultrasonography and operation in 9 cases of foreign bodies of hand or foot. Mean symptom duration periods was 32 months. The location were fingers in 5, palms in 2, hand dorsum in 1, heel in 1 case. In 2 cases, foreign bodies were seen on plane radiographs. In the remaining 7 cases, foreign bodies could be diagnosed by ultrasonography only. Using high resolution stick probe, we performed evaluation on size, location, character of foreign bodies and compared preoperative ultrasonographic findings to intraoperative ones. Results: The site of foreign bodies in preoperative ultrasonography corresponded well with intraoperative findings. Foreign bodies were glass particles in 5, plant thorns in 4, pencil lead in 1. Mean size was 3.9 mm (2~7 mm). Conclusion: Ultrasonography is usefull evaluation tool for diagnosis and treatment in whom residual foreign bodies were suspected.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.55-60
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• 2007

This study used glucomannan as a fat substitute to produce low-fat patties with chicken meat, of which consumer consumption is increasing. In the case of a cooked meat patty, the crude fat content of the group treated with glucomannan was higher than that of a control when cooked. The cooking loss and reduction rate in the diameter of the control patties were higher than those of the group treated with glucomannan. Cohesiveness and chewiness of the group treated with glucomannan were higher than those of the control. As a result of sensory evaluation, there were no significant differences in the tenderness, color, odor and overall taste among the patties, but the juiciness of the group treated with glucomannan was lower than that of the control. There were no big differences in the pH of the patties during the frozen storage period. The volatile basic nitrogen (VBN) content of all of the types of patties gradually increased up to 7.97-8.56 mg% at the fourth week of storage, but these VBN values are hygienically safe. From these results, there was no large quality difference between a low-fat chicken patty to which glucomannan was added and a control. Therefore, it was confirmed that a good quality low-fat chicken patty can be made by controlling the fat and glucomannan content.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.1
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• pp.21-34
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• 2015

Source term analysis should be carried out to prepare the decommissioning of the nuclear power plant. In the planning phase of decommissioning, the classification of decommissioning wastes and the cost evaluation are performed based on the results of source term analysis. In this study, the verification of MCNP/ORIGEN-2 model is carried out for preliminary source term calculation for Wolsung Unit 1. The inventories of actinide nuclides and fission products in fuel bundles with different burn-up were obtained by the depletion calculation of MCNPX code modelling the single channel. Two factors affecting the accuracy of source terms were investigated. First, the neutron spectrum effect on neutron induced activation calculation was reflected in one-group microscopic cross-sections of relevant radio-isotopes using the results of MCNP simulation, and the activation source terms calculated by ORIGEN-2 using the neutron spectrum corrected library were compared with the results of the original ORIGEN-2 library (CANDUNAU.LIB) in ORIGEN-2 code package. Second, operation history effect on activation calculation was also investigated. The source terms on both pressure tubes and calandria tubes replaced in 2010 and calandria tank were evaluated using MCNP/ORIGEN-2 with the neutron spectrum corrected library if the decommissioning wastes can be classified as a low level waste.