• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.166-171
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• 2008

We cannot imagine any more the environment and energy problems are separated from our lives. The various attempts to solve these problems are made all over the world. In this study it was performed to analyze a different heating and cooling load depending on the earth-sheltering method and kind of soils by using TRNSYS 16 as the first step to establish the design guidelines for earth-sheltered architecture, one of the eco-friendly and low energy consuming building types. After performing this simulation, we found the result like this. It is the most lowest load in case of all of walls and roof being earth-sheltered. But considering of the load reduction rate, the effect of earth-sheltering the exterior vertical wall is more efficient for load reduction than the one of earth-sheltering a roof. And we got a lower thermal load in case of a lower heat conductivity of soil. Afterwards we will conduct a further study for boundary condition at earth-sheltered surface and the simulation analysis about the sensitivity variables. The final goal of this study is preparing the design guidelines for earth-sheltered architecture. so we will contribute to building energy saving.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1652-1662
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• 2014

The present study investigated the optimum blending condition of protected fat, choline and yeast culture for lowering of rumen temperature. The Box Benken experimental design, a fractional factorial arrangement, and response surface methodology were employed. The optimum blending condition was determined using the rumen simulated in vitro fermentation. An additive formulated on the optimum condition contained 50% of protected fat, 25% of yeast culture, 5% of choline, 7% of organic zinc, 6.5% of cinnamon, and 6.5% of stevioside. The feed additive was supplemented at a rate of 0.1% of diet (orchard grass:concentrate, 3:7) and compared with a control which had no additive. The treatment resulted in lower volatile fatty acid (VFA) concentration and biogas than the control. To investigate the effect of the optimized additive and feed energy levels on rumen and rectal temperatures, four rumen cannulated Hanwoo (Korean native beef breed) steers were in a $4{\times}4$ Latin square design. Energy levels were varied to low and high by altering the ratio of forage to concentrate in diet: low energy (6:4) and high energy (4:6). The additive was added at a rate of 0.1% of the diet. The following parameters were measured; feed intake, rumen and rectal temperatures, ruminal pH and VFA concentration. This study was conducted in an environmentally controlled house with temperature set at $30^{\circ}C$ and relative humidity levels of 70%. Steers were housed individually in raised crates to facilitate collection of urine and feces. The adaptation period was for 14 days, 2 days for sampling and 7 days for resting the animals. The additive significantly reduced both rumen (p<0.01) and rectal temperatures (p<0.001) without depressed feed intake. There were interactions (p<0.01) between energy level and additive on ruminal temperature. Neither additive nor energy level had an effect on total VFA concentration. The additive however, significantly increased (p<0.01) propionate and subsequently had lower acetate:propionate (A/P) ratios than non-additive supplementation. High concentrate diets had significantly lower pH. Interactions between energy and additive were observed (p<0.01) in ammonia nitrogen production. Supplementation of diets with the additive resulted in lower rumen and rectal temperatures, hence the additive showed promise in alleviating undesirable effects of heat stress in cattle.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.3
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• pp.235-243
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• 1985

A survey of 113 children, aged 4 to 6 years, of the San Cheon a day care center, located in the upland, over populated, poor area of Seoul City, was conducted from July 28 to September 6, 1982, to investigate the dietary and nutritional status, and prevalence of parasitic inpection. House size was 10.1 Pyung; number of households per house, 3.1; number of family member per household, 4.8; and number of family members living together per room, 3.7; on the average. Only 49% of households possess own houses and the others live in the rented houses. About 40% of mothers were engaged income-producing activities within or outside of the home. Mean values of height, weight, arm circumference, girth of chest, and girth of head ranged from 98.4 to 102.2% of KIST mean. However, 13% of the subjects were assessed as undernutrition for 'weight for height'. Mean value of hemoglobin was $12.9{\pm}2.9\;g/dl$ and mean hematocrit value was $35.2{\pm}5.5%$; 17.9% of the subjects were proven to be anemic according to the criteria of the WHO. The positive prevalence of parasitic inpection was 3.3%, significantly lower than that observed in any other area, probably because of community parasitic control project. Intakes of energy and nutrients except thiamin and ascorbic acid were far below RDAs. Carbohydrates for energy provided 71. 2 to 73.8% of total energy intake; protein accounted 11.3 to 12.2%; fat provided 14.5 to 16.6%. Energy intake was divided among breakfast, lunch, evening meal and snack, on the average, in a percentage of 22.0; 23.4; 24.4; 30.2. There was significant correlation between pattern of food consumption and nutrient intakes. The nutrient intakes and quality of foods were highly correlated to the maternal factors, especially mother's educational level. The study suggested that development of nutrition guides for mother and children would be needed to improve nutritional status of those young children.

• KIEAE Journal
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• v.9 no.5
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• pp.47-52
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• 2009

Currently, the environmental issue is of great urgency and sensitivity to the future of our planet. Global warming caused by increased CO2 concentration has an alarming impact on the earth's fragile environment. Droughts throughout the world are causing crop failures. Wildfires now burn with far greater rage. Melting ice caps and glaciers are causing floods. Sea levels are rising. Warm unseasonable winters are threatening our fragile eco-systems. Global warming is no longer a theory; it is an obvious fact we are confronted with every day, and the only way we can prevent it is to take action now. The need to reduce CO2 emissions and try to become carbon neutral is of national importance and leadership. We have become so reliant on fossil fuels that nearly everything we do generates CO2 emissions; from our modern farming practices to transport, to the electricity used to turn on a light, boil water in a kettle or cook our meals. A reduction of 50% of CO2 emissions can easily be achieved by decreasing the energy amount used. We tracked the carbon footprint throughout the electricity and heating energy use in homes and confirmed the amount of carbon emissions according to its consumptions. In order to reduce the carbon generation from housing constructions, such as Passive House concept of buildings or low energy buildings, we must adjust its applications best fit to our conditions. And technical elements should be applied to improve our conditions, and the methodology should be actively sought. Most of all, each individual's recongnition who uses these elements is more important than any other solutions.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.11
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• pp.25-34
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• 2019

It is important to design windows in a reasonable way considering the performance characteristics of the elements of the window rather than just to increase the thermal energy performance of the window. In this study, the Heat-transfer Coefficient as insulation performance of the windows and together with the grade of the glass's SHGC (Solar Heat Gain Coefficient) were analyzed to relate to the energy efficiency performance of the building by azimuth angle. Based on this basic study, the Heat-transfer Coefficient of windows and the SHGC rating of glass were applied to the unit plan of apartment building, and the Heating and Cooling Demand were analyzed by azimuth angle. Apartment plan types were divided into 2 types of Non-extension and extension of balcony. The designPH analysis data derived from the variant of the Heat-transfer Coefficient and SHGC, were put into PHPP(Passive House Planning Package) to analyze precisely the energy efficiency(Heating and Cooling Demands) of the building by azimuth angle. In addition, assuming the 'ㅁ' shape layout, energy efficiency performance and potential of PV Panel installation also were analyzed by floors and azimuth angle, reflecting the shading effects by surrounding buildings. As the results of the study, the effect of Heat Gain by SHGC was greater than Heat Loss due to the Heat-transfer Coefficient. So it is more effective to increase SHGC to satisfy the same Heating Demand, and increasing SHGC made possible to design windows with low Heat-transfer Coefficient. It was also revealed that the difference in annual Heating and Cooling Demands between the low, mid and high floor households is significantly high. In addition to it, the installation of PV Panel in the form of a shading canopy over the window reduces the Cooling Load while at the same time producing electricity, and also confirmed that absolute thermal energy efficiency could not be maximized without controlling the thermal bridge and ventilation problems as important heat loss factors.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.4
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• pp.267-283
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• 2003

This study reviewed the prisoners' dietary lift status under the world panics and Japanese food shortage based on the data of the 1920~1930's prisons' main dish supplies in Chosun, Shinchu boys' prison in Taiwan, Franue correction center in France and Moabit detention house in Germany. 1. The status of main dish food supply of Chosun prisons in 1920~1930's was as follows: 1) Meals were provided with 12 rates depending on the working activities. There were big differences in energy supply between 1$^{st}$ rate of 6045.0 ㎉ in the Mockpo prison and 12$^{th}$ rate of 1855.8 ㎉ in the Masan prison in accordance with the grain supply ratio and the diet rates. 2) The average ratio of energy provided with protein, fat and carbohydrate(PFC ratio) was 20.0: 20.2: 59.8. The supplies of protein and fat were relatively high because main dish was mostly composed of soybean. The soybean was used in 20 ~60％ of main dish in prisons except Gaesung. 3) It was estimated that PFC ratio(8.3: 8.1 : 83.6) in Gaesung boys' prison was not appropriate for growing boys because the soybean supply was low. 2. The overall comparison of nutrition supply of prisons in Chosun, Taiwan, France and Germany was as follows: 1) The daily supplies of energy in Keongsung prison was 3966.5 ㎉, of which the PFC ratio was 18.9: 16.6: 64.5. This showed that the PFC ratio seemed to be balanced, even though the total amount of energy is too high and the ratios of protein and fat were somewhat high and somewhat low, respectively. 2) The main dish of the Taiwan boys' prison was provided with 6 rates and the side dish in the from of weekly cycle menu. The energy intakes from 1$^{st}$ rate of 2862.9 ㎉ to 6$^{th}$ rate of 1388.9 ㎉ were not quite enough for growing boys. It was estimated that the amounts of protein and fat taken were small but the quality was not that bad because animal protein such as protein small fish and fried tofu were supplied. 3) In the French Frenue correction center and the German Moabit detention house, the daily total amounts of energy were 2771.3 ㎉ and 2678.7 ㎉, respectively, which was estimated as appropriate compared with standard energy amount of 3000 ㎉ at that time and the current energy RDA of 2500 ㎉ for adult. The ratio of PFC was 16.2: 12.0: 71.8 in Frenue correction center and 12.4: 14.3: 73.3 in Moabit detention house, which showed that the amount of fat was slightly lacked. From this study, it was suggested that the prisons in Chosun and Taiwan under the Japanese rule and European prisons after the world panic were making an efforts to supply prisoners the appropriate amount of energy. The only question remains is that this data may be from only the food supply plan not from the data the prisoners took in real.eal.

• Journal of Energy Engineering
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• v.25 no.2
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• pp.94-100
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• 2016

ESS(Energy Storage System) is an important source that keeps power supply stable and utilizes electricity efficiently. For example, ESS contributes to resolve power supply imbalance, stabilize new renewable energy output and regulate frequency. ESS is predicted to be expanded to 55.9GWh of installed capacity by 2023, which is 30 times more than that of 2014. To raise competitiveness of domestic ESS industry in this increasing world market, we have disseminated load-shift ESS for continuous power supply imbalance with FR ESS, and also necessity to secure domestic track record is required. However in case of FR ESS, utility of installing thermal power plant is generally generated within 5% range of rated capacity, so that scalability of domestic market is low without dramatic increase of thermal power plant. Necessity of load-shift ESS dissemination is also decreasing effected by surplus backup power securement policy, raising demand for new dissemination model. New dissemination model is promising for $CO_2$ reduction effect in spite of intermittent output. By stabilizing new renewable energy output in connection with new renewable energy, and regulating system input timing of new renewable energy generation rate, it is prospected model for 'post-2020' regime and energy industry. This research presents a policy alternatives of REC multiplier calculation method to induce investment after outlining PV-connected ESS charge/discharge mode to reduce GHG emission, This alternative is projected to utilize GHG emission reduction methodology for 'Post-2020' regime, big issue of new energy policy.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.996-1001
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• 2006

Automatic washing machines have been improved and popularized steadily since the first electric washing machine was produced in the early 1900's. Appliance industry has tried to obtain the performance of washing machine with large capacity, high energy efficiency, low vibration and low noise levels. As the installation peace of a washer becomes closer to the living space, vibration and noise problems become more important challenges. In general, a washing machine has four legs to support its body. Four legs of the washing machine should be attached on a floor. If not so, it may cause severe vibration or walking in the spin-drying process. Unfortunately, the floor of an ordinary house is bumpy in general, and the consumers will not accept bolting washing machines to a foundation; moreover, sometimes they move the location of their washing machines to utility rooms or bath rooms or kitchens and don't care for leveling the legs exactly. In this study, we devise an auto-leg system that prevents the occurrence of abnormal vibration and walking of washing machines. It is simply composed of a spring and a friction damper. Some experiments are implemented to show the dynamic characteristics of the three-dimensional auto-legged washing machine model that is located on the even or uneven ground. A spring parameter is optimized to adjust the length of the auto-leg system automatically up to 10 mm irregularity, and the friction damper is designed to decrease a resonance induced by the spring of the auto-leg system. Some numerical results show that placing the proposed auto-leg system in a washing machine makes good performance with low vibration, as well as low noise, regardless of the unevenness of the floor.

• Journal of Radiation Protection and Research
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• v.45 no.3
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• pp.117-129
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• 2020

Background: Radiation portal monitors (RPMs) involving plastic scintillators installed at the border inspection sites can detect illicit trafficking of radioactive sources in cargo containers within seconds. However, RPMs may generate false alarms because of the naturally occurring radioactive materials. To manage these false alarms, we previously suggested an energy-weighted algorithm that emphasizes the Compton-edge area as an outstanding peak. This study intends to evaluate the identification of radioactive sources using an improved energy-weighted algorithm. Materials and Methods: The algorithm was modified by increasing the energy weighting factor, and different peak combinations of the energy-weighted spectra were tested for source identification. A commercialized RPM system was used to measure the energy-weighted spectra. The RPM comprised two large plastic scintillators with dimensions of 174 × 29 × 7 ㎤ facing each other at a distance of 4.6 m. In addition, the in-house-fabricated signal processing boards were connected to collect the signal converted into a spectrum. Further, the spectra from eight radioactive sources, including special nuclear materials (SNMs), which were set in motion using a linear motion system (LMS) and a cargo truck, were estimated to identify the source identification rate. Results and Discussion: Each energy-weighted spectrum exhibited a specific peak location, although high statistical fluctuation errors could be observed in the spectrum with the increasing source speed. In particular, ¹³⁷Cs and ⁶⁰Co in motion were identified completely (100%) at speeds of 5 and 10 km/hr. Further, SNMs, which trigger the RPM alarm, were identified approximately 80% of the time at both the aforementioned speeds. Conclusion: Using the modified energy-weighted algorithm, several characteristics of the energy weighted spectra could be observed when the used sources were in motion and when the geometric efficiency was low. In particular, the discrimination between ⁶⁰Co and ⁴⁰K, which triggers false alarms at the primary inspection sites, can be improved using the proposed algorithm.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.123-134
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• 2002

An experiment was conducted to establish the most suitable ventilation system for the enclosed nursery pig house in Korea, comparing four different ventilation systems ; i) air enters through perforated ceiling and exhausts through chimney (NA), ii) air enters through perforated ceiling and exhausts through side walls (NB), iii) air enters through perforated ducts and exhausts through side walls (NC) and iv) air enters through perforated ducts and exhausts through chimney(ND). The experiment was carried out during winter and summer separately. The experimental pigs were weaned at fourteen days old in winter (December-February) and at twenty one days old in summer (June-August). The main results of the experiment are as follows : A preliminary experiment showed that in the NC system during summer, air can reach all the pig rooms in the house and the air flow rates of the upper, middle (1.2 m height of the room) and low (at the height of pig stature) parts of the room were measured at 7.0-8.08, over 0.5 and over 0.2 m/s, respectively, which flow rates were much higher(p$<$0.05) than those in other system. At the minimum ventilation efficiency during winter, air flow rates of upper, middle and low parts of the room equipped with the NC system were detected at over 1, less than 0.5 and around 0.07 m/s, respectively. It is concluded that the separated ventilation system air-entering through ducts is the most suitable for the ventilation system of the enclosed nursery pig house and the exhausting system through side walls is more efficient for ventilation than the system through roof. Furthermore, to sustain proper temperature and reduce energy waste as well as heat consumption, a future research should be carried out to develop the environmental control system in relation to developing a heat regulator.