• Journal of the Korean Solar Energy Society
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• v.25 no.1
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• pp.45-55
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• 2005

In the summer, the irradiated solar heat gain through the roof has an effect on the thermal environment of the top floor units of apartment houses. This paper investigated the differences of the indoor air temperature, globe temperature and thermal comfort index between the top floor unit and the middle floor unit by measuring them at the sample units on the condition that all the openings of the units are opened. The purpose of this paper is to provide quantitative data about the irradiated solar heat gain during the summertime through the roof of an apartment house and these data to be the source to reevaluate the appropriate roof insulation efficiency. From this study, we obtained three brief results as follows. Indoor air temperature difference between the two sample units shifts a day. Indoor air temperature at the top floor unit is $0{\sim}1.8^{\circ}C$ higher than that of the middle floor unit from 12:00 p.m. to 12:00 a.m. and $0{\sim}2.8^{\circ}C$ lower from 12:00 a.m. to 12:00 p.m. The evaluation of the indoor thermal comfort index and the globe temperature shows similar results as the indoor air temperature measuring. Results of this experiment verified the actual existence of indoor air temperature difference between the top floor unit and the middle one and this difference comes from the heat storage of the roof.

• Nutrition Research and Practice
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• v.5 no.4
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• pp.322-328
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• 2011

The aim of this study was to use the Healthy Eating Index-2005 (HEI-2005) to assess diet quality and determine the relationship between the HEI-2005 and the energy and nutrient intakes of adolescents. A cross-sectional study was conducted on 1,104 healthy adolescents, mean age of $15.8{\pm}1.24$ years. Dietary intake was measured with the 24-hour dietary recall method, and dietary quality was assessed by means of the HEI-2005. Diet quality scores ranged from 23.7 to 77.5. The mean score was found to be $51.5{\pm}9.07$ according to the HEI-2005. There were no differences according to gender, 42.8% had a poor diet and 57.2% had a diet that needs improvement. No subjects had a "good diet". Lower mean subgroup scores were found for whole grains, total vegetables, total fruits, dairy products, and meat and beans. Fruits and vegetables scores were significantly high in girls, whereas sodium, oil, and meat and beans scores were significantly high in boys. Total HEI-2005 scores were increasingly associated with parental education level when age and gender were adjusted. There was a negative correlation between HEI-2005 scores and age, total energy intake, and fat intake. Positive correlation was only observed in the HEI-2005 scores for protein and dietary fibre intakes. Consequently, the overall diet quality and nutritional habits of Turkish adolescents need modification and improvement. In the family, measures should be initiated by the government, including advertisements and campaigns.

• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1125-1132
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• 2017

In a situation where the severity and frequency of drought events getting stronger and higher, many studies related to drought forecast have been conducted to improve the drought forecast accuracy. However it is difficult to predict drought events using a single model because of nonlinear and complicated characteristics of temporal behavior of drought events. In this study, in order to overcome the shortcomings of the single model approach, we first build various single models capable to explain the relationship between the meteorological drought index, Standardized Precipitation Index (SPI), and other independent variables such as world climate indices. Then, we developed a combined models using Stochastic Gradient Descent method among Ensemble Learnings.

• Journal of Energy Engineering
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• v.13 no.1
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• pp.75-81
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• 2004

ZZFCa sorbents for hot gas desulfurization in IGCC were prepared by adding calcium oxide to ZZF sorbent in order to improve its attrition resistance in this study. ASTM attrition test for the sorbent was performed at several different weight percentages of CaO to investigate the attrition characteristics of ZBFCa sorbents as a function of CaO content. Attrition index of ZZF without CaO was 28.3% and its collected attrition index was 10.8％. ZZFCa-3 containing 3 wt% CaO showed the lowest attrition index (AI=17.3％, CAI=8.8％) in the test. From the results of SEM morphologies and particle size distribution measurements, ZZFCa-3 maintained a fine shape and a desirable average particle size even after attrition test. In the experiments of sulfidation/regeneration for ZZFCa-3 sorbent concentration of hydrogen sulfide in coal gas was lowered from 10000 ppm to below 1 ppm. Sulfur removing capacity was about 28.8 g S/100 g sorbent. Neither formation of CaSO$_4$ was observed in XRD measurement nor SO$_2$ slippage was observed during sulfidation process.

• International Journal of Highway Engineering
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• v.18 no.5
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• pp.83-93
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• 2016

PURPOSES : The aim of this article is to compare and identify eco-friendly competitiveness between (regional) motorway and high-speed rail(HSR) from the perspective of $CO_2$ emission in the Republic of Korea. METHODS : In order for an analysis of low-carbon competitiveness between the two modes, $CO_2e$ emission, $CO_2eppk$ (equivalent $CO_2$ gram per passenger kilometer), is employed as a comparison index. As for HSR, the index is calculated based on the passenger transport data and the gross of $CO_2e$ produced by Kyungbu high-speed line in 2013. Additionally, the gross of $CO_2e$ is computed by the greenhouse gas emission factors of domestic electricity generation mix. Regarding the index of motorway, it is directly calculated using both the official $CO_2e$ emission factor and the passenger-car occupancy of motorway. RESULTS : The results revealed, in the case of inter-regional transport, that the $CO_2e$ emission of displacement-based cars is 54.9% less than that of HSR, as the domestic electric power systems heavily relies on the thermal power plants over 66%. Note that internal combustion engines commonly used for vehicles are more energy-efficient than steam-driven turbines usually utilized for thermal power generation. CONCLUSIONS : It can be seen, at the very least in our study, that HSR has no superiority over motorway in the case of $CO_2e$ emission under the situations of domestic electricity generation mix. In addition, advanced eco-friendly vehicles have strong advantages over HSR. Therefore, all-out efforts should be made to develop and harvest renewable energy sources in order to achieve low-carbon HSR, sparing fossil fuels.

• Journal of KIISE:Databases
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• v.35 no.3
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• pp.208-217
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• 2008

Sensors have a function to gather environment-related information operating by small-size battery in sensor networks. The issue related with energy is still an important in spite of the recent advancements in micro-electro-mechanical-system(MEMS) related techology. Generally it is assumed that replacement or rechargement of battery power in sensor is not feasible and a message send operation may spend at least 1000 times battery than a local operation. Thus, there have been several kinds of research efforts to lessen the number of unnecessary messages by maintaining the information of the other neighboring(or all) sensors. In this paper, we propose an index structure based on parent-children relationship to the purpose. Namely, parent node gathers the set of location information and MBA per child. It's named PH and may allow to process the range query with higher accurate and small size information. Through extensive experiments, we show that our index structure has better energy consumption.

• Environmental and Resource Economics Review
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• v.26 no.1
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• pp.1-35
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• 2017

This study investigates a decomposition analysis of the determinants of the reduced $CO_2$ emissions in seven OECD countries that implemented carbon taxes from 1995 to 2013. Recent studies on decomposition analysis of changes in $CO_2$ emissions focused on technology-based physical factors; however, this study analyzes the effects of a carbon tax as an economic factor. According to the results obtained by using the Log Mean Divisia Index, the energy intensity effect and the carbon tax effect contributed the most towards the reduction of total $CO_2$ emissions in the seven OECD countries. The results for each country show that the emissions decreased due to the energy intensity effect, while the effects of carbon tax and carbon tax revenues differed by policy and environment of the countries.

• Journal of Nutrition and Health
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• v.33 no.1
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• pp.49-58
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• 2000

The purpose of this study was to investigate the relationship among urn leptin, nutritional status, and urn lipids, glucose of 99 middle school girls residing in Kyluggi-do, Korea. Subjects were assigned to one of three groups such as underweight(BMI < 20, n=38), normal(20$\leq$BMI<25, n=36) and over weight(BMI$\geq$25, n=25) groups. The nutritional status of the subjects was evaluated by anthropometric measurements, questionnaires, 24-hr dietary recalls and blood anal),sis. The results were as follows : The mean age, body weight, height and BMI were 13.93 years, 55.19kg, 158.40cm and 21.96kg/㎡ respectively. The mean menarche age of the subjects was 12.64 years and the mean daily energy intake was 94.22% off RDA for Koreans. The energy ratio from carbohydrate fat and protein was 63: 24: 13. Underweight group showed the lowest intakes of oils and fats among three groups(p<0.05). The mean serum levels of leptin, glucose, total cholesterol, HDL-cholesterol. LDL-cholesterol and triglyceride were 10.57ng/ml 78.80mg/dl, 12.29mg/dl, 48.07mg/dl, 93.50mg/dl and 78.61mg/d1, respectively. The mean atherogenic index was 2.37. There were significant increases in serum leptin, glucose, LDL-cholesterol, triglyceride and atherogenic index of subjects with increases in their BMIs. Serum leptin showed a significantly positive correlation with BMI(p<0.001), body fat percent(p<0.001). When BMI was adjused, serum leptin showed a significantly positive partial correlations with intakes of animal protein(p<0.05), milks and animal foods(p<0.05), Serum leptin showed a significantly positive correlation with serum glucose(p<0.05) total cholesterol(p<0.01), LDL-cholesterol(p<0.001), triglyceride(p<0.001) and atherogenic index(p<0.001), however, it had significantly negative correlations with HDL-cholesterol(p<0.05). Therefore, these results suggest that the increase of serum levels of leptin may elevate the risk of cardiovascular disease and lipids and some nutrient intakes may be related with serum leptin levels. (Korean J Nutrition 33(1) : 49-58, 2000)

• Journal of Nutrition and Health
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• v.30 no.4
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• pp.451-457
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• 1997

This study was designed to investigate the effect of the ratio of energy from carbohydrate to total calories on dietary intake, obesity index, blood pressure, and blood lipid content in cardiovascular disease patients over 35 years old. A total of 552(227 male, 325 female) subjects were divided into three groups according to carbohydrate/total energy ratio : carbohydrate ratios below 25 percent were in the low carbohydrate group( <61.1%), between 25 and 75 percent carbohydrate were medium($\geq$61.1-<74.7%), and higher than 75 percent were in the high carbohydrate group($\geq$74.7%). The anthropometric data, nutrient intake, serum lipid levels, and blood pressure of each group were compared with one another. For men and women with high carbohydrate intakes, Inadequate nutritional intake was observed. Abdominal fat accumulation and blood TC level for men in the high carbohydrate group were higher than in medium or low carbohydrate groups. Therefore, it seems that high carbohydrate intake may produce adverse effects on abdominal fat accumulation and blood lipid patterns. Blood pressure, however, was significantly higher for women in low and high carbohydrate groups than in medium carbohydrate group. These results suggest that extremely high and low carbohydrate intake may raise the risk of cardiovascular disease and that it is necessary to consume nutritionally balanced meals. This can be done by controlling the ratio of dietary carbohydrate at a medium level in order to prevent and/or to reduce the risk.

• Elastomers and Composites
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• v.48 no.4
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• pp.249-255
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• 2013

Hydroxypropyl terminated PDMS was synthesized by the hydrosilylation reaction with allyl alcohol in the presence of Karstedt's catalyst. And them, an one-pot reaction with HDI isocyanurate trimer and hydroxyethyl methacrylate was conducted to give a silicone-modified urethane acrylate oligomer (PUA oligomer) having 9000 g/mol, weight average molecular weight. The synthesized PUA oligomer was characterized by using FT-IR and GPC. The UV-curable coatings were prepared by PUA oligomer blending with a reactive monomer (phenylthioethyl acrylate) under the different mole ratios. It was found that the refractive index of cured film increased when the reactive monomer was added but there was no relationship between the refractive index and amount of reactive monomer. Also, their transmittance for cured films was not change as increasing the content of reactive monomer.