• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.243-248
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• 2008

The purpose of this study is to introduce alternative cost-effectiveness analysis method of DSM investment programs. This alternative method is Value Test method which consider the effects of DSM investment program on customer value. And this method was applied for actual DSM investment program in natural gas domain. By utilize this method to evaluate cost-effectiveness of DSM investment programs, it is expected to make right decision to enforce and complement those programs.

• Journal of the Korean Solar Energy Society
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• v.33 no.1
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• pp.48-56
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• 2013

Energy consumption analysis of multi-family apartment is an important area of research for the design of energy-saving housing. In this study, we selected a universal type of Flat-type apartments and analyzed the heating energy consumption of variables such as U-value, G-value, infiltration rate, heating setpoint and boiler efficiency with EnergyPlus and eQUEST. With these results, we identify the characteristics of EnergyPlus and eQUEST and provided base data for the design of energy-saving housing. The results indicate that infiltration rate is the most important factors to consider. And eQUEST heating energy consumption is approximately 10% higher compared to the EnergyPlus under same condition.

• Preventive Nutrition and Food Science
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• v.5 no.2
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• pp.100-104
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• 2000

The caloric contribution of diets supplemented with sucrose, corn oil, or tallow with or without additional calcium was examined using female CD1 weanling mice. Mice were limit-fed a semi-purified diet alone or with added isocaloric amounts from sucrose, corn oil, or tallow for 28 days. In addition, diets with suppelmental fat contained either 0.60% or 1.5% calcium. Fecal fat and fecal soap excretions were greater (p<0.06) for mice fed tallow than for those fed corn oil. Mean metabolizable energy values for sucrose, tallow, and corn oil averaged 4.01, 7.96, and 8.94 kcal, respectively. Retention of digested energy from sucrose, tallow and corn oil averaged 13%, 10% and 21%, respectively. Hence, per gram of added nutrient, retained energy from tallow averaged 1.60 and that from corn oil averaged 4.11 times that of added sucrose. Retained energy from added corn oil was greater (p<0.01) than from added tallow. On a retained energy basis, the relative value for corn oil was greater and the relative value for tallow was less than the metabolizable energy ratio of fat to carbohydrate proposed by Atwater of 2.25.Added calcium depressed(p<0.01) digestibilities of both dry matter and energy with a greater(p<0.01) effect on tallow than on corn oil. These findings imply that the source of fat and calcium in the diet influence the avail-ability energy in diets and should be considered in feed formulations.

• Progress in Superconductivity and Cryogenics
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• v.21 no.3
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• pp.1-5
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• 2019

The superconductor stability theories are consistently described by the integral formula. If the defined stability function is a simple decreasing function, it becomes a cryogenic stability condition. If the stability function has a maximum value and a minimum value, and the maximum value is less than 0, then it is a cold-end recovery condition. If the maximum value is more than 0, it can be shown that the unstable equilibrium temperature, that is, the MPZ (minimum propagation zone) temperature distribution can exist. The MPZ region is divided into two regions according to the current ratio. At the low current ratio, the maximum dimensionless temperature is greater than 1, and at the relatively high current ratio, the maximum dimensionless temperature is less than 1. In order to predict the minimum quench energy, the dimensionless energy was obtained for the MPZ temperature distribution. In particular, it was shown that the dimensionless energy can be obtained even when the MPZ maximum temperature is 1 or more.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.6
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• pp.562-574
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• 2023

Carbon neutrality has been suggested to overcome the global climate crisis caused by global climate change. Hydrogen energy is a major way to achieve carbon neutrality, and the developments and policies of hydrogen technology have been proposed to achieve this goal. To commercialize hydrogen energy resources, it is necessary to understand the overall value chain composed of hydrogen production, storage, and utilization and to present the direction of technological developments. In this paper the hydrogen strategies of major countries, including Europe, the United States, Japan, China, and South Korea will be analyzed, and hydrogen technologies by value chain will also be explain. This paper will contribute to understanding the overall hydrogen policy and technology, as both policy and technology are summarized.

• Journal of the Korean Solar Energy Society
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• v.29 no.6
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• pp.102-109
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• 2009

The research on meteorological data in Korea has been carried out but without much consistency and has been limited to some areas only. Of relatively more importance has been the area in the utilization of the solar energy, however, the measurement of the global solar horizontal irradiation has been quite limited. In the current study, the actually measured value of the global solar horizontal irradiation from the meteorological data and the theoretically calculated value of the global solar horizontal irradiation from the cloud amount will be analyzed comparatively. The method of analysis will employ the standard meteorological data drafted by the Korean Solar Energy Society, the standard meteorological data from the presently used simulation program and the corresponding results have been compared with the calculated value of the global solar horizontal irradiation from the cloud amount. The results of comparing the values obtained from MBE(Mean Bias Error), RMSE(Root Mean Squares for Error), t-Statistic methods and those from each of the standard meteorological data show that the actually measured value of the meteorological data which have been converted into standard meteorological data with the help of the ISO TRY method give the monthly average value of the global solar horizontal irradiation. These values compared with the monthly average value from the IWEC from the Department of Energy of the USA show that the value of the global solar horizontal irradiation in the USA is quite similar. In the case of the values obtained from calculation from the cloud amount, the weather data provided by TRNSYS, except only slight difference, which means that the actually measured values of the global solar horizontal irradiation are significant. This goes to show that in the case of Korea, the value of the global solar horizontal irradiation provided by the Korea Meteorological Administration is will be deemed correct.

• Journal of the Korean Geosynthetics Society
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• v.11 no.4
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• pp.55-62
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• 2012

In this application study, field pilot tests were performed to evaluate the validity of a proposed formula between the exerted electrical energy and SPT N-value based on the result of the basic study. Measurement sensors and recording system were developed to obtain exerted motor current and drilling depth in a field. By using the correlation formula proposed in the basic study, the measured motor current and boring speed were applied to predict SPT N-value and the predicted N-values were compared to SPT N-value of site exploration. From the comparisons it is verified that the exerted electrical energy to bore ground might be used to predict SPT N-value and pile tip location.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.461-468
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• 2023

Supplying an appropriate amount of feed is an economical and environmentally friendly by increasing the nutrient digestibility of livestock and reducing nutrients released from overfeeding. Therefore, this study was conducted to determine the nutrient digestibility according to dietary feeding levels of Hanwoo steers. Three treatments in feeding trial were used feeding amount based on the maintenance energy level of the Korean feeding standard for Hanwoo (2022): 100% (control, CON), 140% (treatment 1, TRT1), and 190% (treatment 2, TRT2). The experiment was designed in replicate 3×3 balanced Latin square designs using six Hanwoo steers. In this study, energy value was predicted according to treatment groups. In addition, nutrient digestibility and energy value were measured through a feeding trial to Hanwoo steers. All energy values, including total digestible nutrients and digestible energy, were predicted to decrease linearly with increasing feeding levels. TRT2 showed lower digestibility than CON for dry matter, crude protein, non-fiber carbohydrates, and total digestible nutrients in the feeding trial (p<0.05). However, there was no significant difference between CON and TRT1. Total digestible nutrients (TDN) and digestibility of feed are set based on the maintenance energy. However nutrient digestibility and TDN decreased when feeding level increased by more than 190% compared to maintenance energy in this study. Therefore, it is necessary to correct the TDN by considering the feeding level when mixing the feed.

• Geomechanics and Engineering
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• v.17 no.4
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• pp.393-403
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• 2019

The cycling impact test of red sandstone soil under different axial pressure and different impact loads are conducted to reveal the mechanical properties and energy consumption mechanism of red sandstone soil with static-dynamic coupling loading. The results show that: Under the action of different axial pressure and different impact loads, the peak stress of the specimen increases, and then tends to be stable with the times of impact. With the increase of impact times, the specific energy absorption value of the red sandstone soil specimen is increased first and then gentle development trend. When the impact loads are certain, the larger the axial pressure is, the smaller the peak value of energy absorption, which indicates that the energy utilization rate is not high under the condition of large axial pressure. Through the analysis of energy utilization, it is found that the smaller the impact load, the higher the energy utilization rate. The greater the axial pressure, the lower the energy utilization rate. when the axial pressure is large, the impact loads corresponding to the maximum values of reflectivity, transmissivity and absorptivity are the same. The relationship between reflectivity and transmissivity is negatively correlated.

• Korean Journal of Community Nutrition
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• v.3 no.3
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• pp.368-379
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• 1998

The purpose of this study was to assess the energy value of breakfast and its relation to total daily nutrient intake and serum lipid. Dietary intakes were evaluated through the 3-day dietary recalls(interview for 1day and self-report for 2 days) from 333 Korean urban adults aged 20-49 year. Serum lipids in fasting blood samples were measured form 98 of those 333 adults. Low energy breakfast(<15% of daily energy intake) was consumed by 22.6% of males and 18.5% of females. 59.4 of males and 43.3% of females consumed a breakfast of average energy intake(15-25% daily energy intake) ; and 18.1 of males and 38.2% of females consumed a significant contribution to a total daily nutrient intake. The daily nutrient intake except crude fiber and vitamin A, B, B, and C in males and except vitamin C in females significantly increased as the energy value of breakfast increased. The differences in energy and nutrient intakes at breakfast were not made up for by other meals. To make matters worse, the satisfactory-energy breakfast group took more energy at dinner compared with the low-energy and average-energy breakfast group took more energy at dinner compared with the low-energy and average-energy breakfast groups in females. Among serum lipid parameters, TG was negatively correlated with energy provided at breakfast, and total cholesterol and LDL-cholesterol had a negative correlation with energy and carbohydrates provided at breakfast in males. For females TG was positively correlated with the ratio of carbohydrates to energy at breakfast but negatively correlated with the ratio of fat to energy at breakfast. These results suggest that satisfactory energy intakes at breakfast have positive effects on the adequacy of daily nutrient intake and may positively affect the serum lipid status.