• Nuclear Engineering and Technology
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• v.52 no.4
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• pp.689-699
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• 2020

In this work, new multi-recycling options of TRU nuclides using PWR fuel assemblies comprised of MOX and FCM (Fully Ceramic Micro Encapsulated) fuels are suggested and neutronically analyzed. These options do not use a fully recycling of TRU but a partial recycling where TRUs from MOX fuels are recycled while the ones from FCM fuels are not recycled due to their high consumption rate resulted from high burnup. In particular, additional external TRU feed in MOX fuels for each cycle was considered to significantly increase the TRU consumption rate and the finally selected option is to use external TRU and enriched uranium feed as a makeup for the heavy metal consumption in MOX fuels. This hybrid external feeding of TRU and enriched uranium in MOX fuel was shown to be very effective in significantly increasing TRU consumption rate, maintaining long cycle length, and achieving negative void reactivity worth during recycling.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.4
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• pp.115-120
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• 2010

The reduction rate of fuel consumption by showing the fuel injection data for driver was measured in this study. The fuel injection data are composed of injection period, real time fuel economy and average fuel economy. The fuel consumption was measured by processing the voltage signal of injector and driven distance by GPS sensor. The fuel consumption was reduced by driving more carefully, i.e driving more steady without sudden acceleration and deceleration watching these fuel injection data. The reduction rate was up to 37% and the rate increased as the driver is customed to this driving pattern.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.11
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• pp.605-611
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• 2017

The purpose of this study is to calculate the energy consumption rate based on data regarding energy use in office buildings, and to confirm the general characteristics of energy consumption. The energy consumption rate of the building is calculated by dividing the energy consumption by the floor area. The energy consumption rate of small-sized office buildings was calculated as $101.48{\sim}201.55kWh/m^2{\cdot}year$ and in the case of medium-sized buildings, the range was $92.77{\sim}177.89kWh/m^2{\cdot}year$. In the case of small buildings, it was found that the energy consumption was $73.24kWh/m^2{\cdot}year$ in electronic device, $34.31kWh/m^2{\cdot}year$ in hot water supply, and $18.37kWh/m^2{\cdot}year$ in heating. In the case of medium-sized buildings, electronic devices was $73.08kWh/m^2{\cdot}year$, lighting was $18.35kWh/m^2{\cdot}year$ and heating, $15.37kWh/m^2{\cdot}year$. In all of the study buildings, the peak heating energy use was observed from 8:00 a.m. to 10:00 a.m during the winter, and the peak power management was required. Energy use at and around the midnight hour is confirmed to be 40~60% of weekly working hours, so it is necessary to manage power use at night time as well as during the day. In order to improve the accuracy of future studies, it is necessary to make efforts to secure the data with standardized energy measuring units for the various type of buildings.

• Journal of Power System Engineering
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• v.19 no.3
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• pp.29-35
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• 2015

Environmental pollution is produced by consumption of fossil fuel, therefore alternative fuels is interested for development of new energy resources and reduction of exhaust emissions for air pollution prevention. Biofuels are produced from new vegetable oil and animal fat, may be used as fuel without change of engine structure in diesel engine. In this paper, the test results on specific fuel consumption, combustion characteristics of neat diesel oil and biodiesel blends(10 vol.% biodiesel and 20 vol.% biodiesel) were presented using four stroke, direct injection diesel engine, especially this biodiesel was produced from biodiesel fuel at our laboratory by ourselves. This study showed that specific fuel consumption is increased slightly, on the other hand cylinder pressure, rate of pressure rise, rate of heat release and soot were decreased slightly in the case of biodiesel blends than neat diesel oil.

• Culinary science and hospitality research
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• v.23 no.8
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• pp.54-66
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• 2017

The purpose of this study was to investigate the nutrient intake status and factors affecting the consumption of commercial staple food for Korean adults using the Korean National Health and Nutrition Examination Survey data from 2010 to 2014. As a result of analyzing the frequency of consumption of commercial staple food, in 27.578 subjects, 75.5% of them did not eat it once a day, 21.7% of the subjects consumed once a day, and more than two times showed 2.8%. According to the results of age, the higher the age, the higher the rate of not consuming commercial staple food, and the lower the age, the higher the rate of consumption of commercial staple food(p<0.0001). In addition, the rate of consumption of commercial staple food was higher in cities than in rural areas. The higher the education level, the higher the proportion of commercial staple food. The intake of rice, noodles, and bread increased significantly as the frequency of consumption of commercial staple foods increased. Protein, fat, riboflavin, and niacin showed significant differences with increasing frequency of commercial staple food in nutrient intakes(p<0.0001). As the number of commercial staple food increased, the intake of grains, egg products, milk and dairy products, beverages and other food groups increased and the consumption of vegetables decreased significantly.

• Journal of the Korean Dietetic Association
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• v.21 no.3
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• pp.194-202
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• 2015

The study examined dietary intake, satiety rate, and eating rate using rice bowls with an elevated bottom (diet rice bowl) and rice bowls with an elevated bottom and monitoring line (monitoring rice bowl). The monitoring rice bowl was used to help subjects monitor amounts they had eaten as they ate. Eighteen normal weight college female students participated in this study once a week for 2 weeks. Three hundred grams of fried rice in a diet rice bowl (1st week), and 300 g of fried rice in a monitoring rice bowl were served to the participants over 2 consecutive weeks. After each lunch, dietary intake, satiety rate, and eating rate were measured. The consumption amount of fried rice was 261.6 g in the diet rice bowl group, and 264.8 g in the monitoring rice bowl group. There was no significant difference in fried rice intake between the two groups. The satiety rate of fried rice in the monitoring rice bowl group was significantly higher than that of the diet rice bowl group after 1 hour and 2 hours (P<0.05). The eating rate of the diet rice bowl group (21.3 g/min) was significantly faster than that of the monitoring rice bowl group (18.7 g/min) (P<0.05). This result shows that food consumption monitoring can affect not only eating rate but also the subjective feelings of satiety after meal eating. Although more study is needed, these data suggest consumption monitoring in a rice bowl may help to control obesity and weight.

• Journal of Korean Society of Forest Science
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• v.81 no.3
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• pp.280-286
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• 1992

When the social cost-benefit analysis is applied for analyzing the public forestry investment, the choice of discount rate to be used in analysis is critical. In this paper, the social discount rate discussed in the public economics was introduced and the social time preference rate as a measure of that was estimated for Korea. The component parameters of the model used are : the elasticity of social marginal utility of consumption and the growth rate of real consumption. The results for the social time preference rate and the elasticity of social marginal utility of consumption are 6.2% and -1.38, respectively, which are plausible and thus can be used as a useful basis in establishing rational resource allocation policies.

• Korean Journal of Community Nutrition
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• v.18 no.5
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• pp.467-477
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• 2013

This study examined the health-related factors and nutritional status of 89 single women workers in their 20's who work night and day shift at the take-out coffee shops and the 89 single women office workers. The results of the study are summarized as follows: The shift-workers showed lower rate of office tenure (p < 0.001), income (p < 0.001), job satisfaction (p < 0.05), weight (p < 0.05), and higher rate of weight change (p < 0.001) than the non shift-workers. The shift-workers showed lower rate of of exercise (p < 0.001), sleeping hours (p < 0.01), and good health condition (p < 0.01), and higher rates of smoking (p < 0.001), presence of disease (p < 0.001), gastric and intestinal illnesses (p < 0.001) than the non shift-workers. More than 88.8% of the shift workers answered that they ate alone (p < 0.001). The shift workers showed lower rate of regularity of meal (p < 0.001), balanced diet (p < 0.001), and mealtime (p < 0.001), and higher rate of skipping breakfast (p < 0.001), consumption of salty and spicy food (p < 0.001), and overeating (p < 0.01) than the non shift-workers. The shift workers consumed (p < 0.001) less frequently rice, soup and side dishes, and more frequently noodles and snack, bread than the non-shift-workers. The shift workers showed lower rate of consumption of beer (p < 0.01), and higher rate of consumption of coffee (p < 0.001), tea (p < 0.01) and soju (p < 0.001) in once a week or more intakes than the non-shift-workers. The shift workers showed higher rate of consumption of carbohydrates (p < 0.05), and calcium (p < 0.05) and lower rate of consumption of protein (p < 0.05), fiber (p < 0.05), vitamin C (p < 0.05), and folate (p < 0.05) intakes than the non-shift-workers.

• Journal of Bio-Environment Control
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• v.2 no.1
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• pp.27-36
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• 1993

Carbon dioxide enrichment for greenhouse crops has generally been a standard commercial practice for many years. Vegetable crops such as tomato, cucumber, and lettuce respond positively to the $CO_2$ enrichment. But improper $CO_2$ enrichment leads to physiological damage and economical loss. This study was carried out to develop a $CO_2$ concentration control algorithm considering growth stage and efficiency. The measurand was $CO_2$ consumption rate and top fresh weight that represents growth stage. The weight of top fresh lettuce as a whole in the tray was measured through a non-destructive method. The demand in $CO_2$ concentration according to growth stage was investigated. The results are summarized as follows. 1. The $CO_2$ consumption rate could be measured within the error of $\pm$ 15.4mg$CO_2$/hr in the range of $CO_2$ concentration of 500-1500ppm. 2. The weight of top fresh lettuce could be measured within the error $\pm$ 4.3g in the range of 0-1400g. 3. The $CO_2$ control model developed could determine an economical $CO_2$ supply rate considering $CO_2$ consumption rate and leakage rate. 4. The $CO_2$ control algorithm based on the control model was composed of feedforward control for maintaining a stable $CO_2$ concentration level, and feedback control with $CO_2$ consumption rate and top fresh weight for adapting to the change in $CO_2$ demand by growth stage. 5. For the performance test with the developed control algorithm on lettuce the decrease in $CO_2$ supply rate was obtained without a significant decrease in top fresh weight.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.10
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• pp.914-922
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• 2004

In this study, measurement and analysis of energy consumption of a research building have been conducted. The energy audit procedure includes monitoring of electricity and LNG consumption over a period of three yews from 2000 to 2002. Data acquisition system for collecting energy consumption data of HVAC equipment such as chillers, fan filter units, AHUs, cooling towers, boilers, pumps, fan coil units, air compressors and etc. has been installed in a building located in Seoul. Data collected at an interval of 1 minute are analyzed for studying the energy consumption pattern of a research building. Percentage of energy consumption of all HVAC equipment is $51.0\%$ in 2000, $55.4\%$ in 2001, and $62.3\%$ in 2002, respectively. Electricity consumption of chillers accounts for $17.6\%$ of the total energy consumption, which is the largest. Annual energy consumption-rate per unit area is $840.5Mcal/m^2{\cdot}y$ in 2000, $1,064.8Mcal/m^2{\cdot}y$ in 2001, and $1,393.0Mcal/m^2{\cdot}y$ year 2002, respectively.