• 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.

• Journal of the Korean Solar Energy Society
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• v.38 no.2
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• pp.55-66
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• 2018

South Korea aims to shift the 20 percent of electricity supplement from the fossil fuel including the nuclear to renewable energy systems by 2030. In order to realize this agenda in the buildings, the plus energy house is necessary to increase the renewable energy supplement beyond the zero energy house. This paper suggested KePSH (KIER Energy-Plus Solar House) and energy performance of house and renewable energy systems was investigated. The KePSH has the target of generating 40% surplus energy than the conventional house energy consumption. The plus energy house is the house that generates surplus energy from the renewable energy sources than that consumes. In order to minimize the cooling and heating load of the house, the shape design and passive parameters design were conducted. Based on the experimental data of the plug load in the typical house, the total energy consumption of the house was estimated. This paper also suggested renewable energy sources integrated HVAC system using air-source heat pump system. Two cases of renewable energy system integration methods were suggested, and energy performance of the cases was investigated using TRNSYS 17 program. The results showed that the BIPV (building integrated photovoltaic) system (i.e., CASE 1) and BIPV and BIST system (i.e., CASE 2) shows 42% and 29% of plus energy rate, respectivey. Also, CASE 1 can generate 59% more surplus energy compared with the CASE 2 under the same installation area.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.13 no.3
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• pp.1-8
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• 2017

Variable refrigerant flow (VRF) systems have recently attracted attention in many countries due to a variety of advantages over conventional system. Especially, the water-cooled VRF heat pump, including geothermal heat pump, is a system that accurately controls the flow rate of refrigerant for the improved efficiency under part load operation. This paper describe the process of generating the cooling and heating energy performance curve coefficients and performance expressions for modeling water cooled VRF system using EnergyPlus. Through this study, the process for generating performance curves can be implemented into EnergyPlus or other comparable building energy analysis tools for the long-term evaluation of heat pump under dynamic conditions.

• Korean Journal of Community Nutrition
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• v.16 no.2
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• pp.206-214
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• 2011

This study was conducted to investigate the effect of the NutriPlus+ Program and to observe how the improved statuses were maintained after the program's termination. The subjects were infants and their parents, who have participated in the NutriPlus+ Program conducted by South Healthcare Center in Po-hang for longer than six months, during the period 2007 - 2010. The survey was conducted with questionnaires, and scores were tabulated from each question. After the intervention of the program, scores representing degrees of nutrition knowledge and nutrition attitude increased. The rate of nutritional risk by anthropometric measurement decreased, and the prevalence rate of anemia was significantly decreased as well. The number of subjects lacking any nutrients, except for iron and vitamin C, decreased, which indicates that the NutriPlus+ Program was effective. After enough time had passed after the intervention's completion; however, the scores of nutrition knowledge and nutrition attitude decreased. The number of subjects with low height and weight (proportional to their age) relatively decreased, and the prevalence rate of anemia increased slightly. The number of subjects lacking in energy and calcium consumption increased as well, which indicates that the effect of the NutriPlus+ Program was not maintained after the program's termination.

• Journal of Energy Engineering
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• v.28 no.4
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• pp.13-18
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• 2019

The high energy penalty in amine-based post-combustion CO₂ capture process is hampering its industrial scale application. An advanced process is designed by intensive heat integration within the conventional process to reduce the stripper duty. The study presents the technical feasibility for stripper duty reduction by intensive heat integration in CO₂ capture process. A rigorous rate-based model has been used in Aspen Plus® to simulate conventional and advanced process for a 300 MW coal-based power plant. Several design and operational parameters like split ratio, stripper inter-heater location and flowrate were studied to find the optimum values. The results show that advanced configuration with heat integration can reduces the stripper heat by 14%.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.348-353
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• 2011

Recently the renewable energy has been used widely and the importance of renewable sources is bigger than before. So the government enforced a law to the public buildings to install the renewable energy facilities. The capacity of facilities is 5% of total construction cost until April 13, 2011. Since then, the government changed the law from 5% of total construction cost to 10% of predicted energy usage because of the practical use of the renewable energy facilities. So, in this study, the comparative analysis is conducted according to the law to the building installed PV system through the EnergyPlus simulation.

• Journal of Radiation Protection and Research
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• v.34 no.4
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• pp.155-164
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• 2009

In this paper, we used computerized glow curve deconvolution (CGCD) software with several models for the simulation of a TL glow curve which was used for analysis. By using the general approximation plus model, parameters values of the glow curve were analyzed and compared with the other models parameters (general approximation, mixed order kinetics, general order kinetics). The LiF:Mg,Cu,Si and the LiF:Mg,Cu,P material were used for the glow curve analysis. And we based on figure of merits (FOM) which was the goodness of the fitting that was monitored through the value between analysis model and TLD materials. The ideal value of FOM is 0 which represents a perfect fit. The main glow peak makes the most effect of radiation dose assessment of TLD materials. The main peak of the LiF:Mg,Cu,Si materials has a intensity rate 80.76% of the whole TL glow intensity, and that of LiF:Mg,Cu,P materials has a intensity rate 68.07% of the whole TL glow intensity. The activation energy of LiF:Mg,Cu,Si was analyzed as 2.39 eV by result of the general approximation plus(GAP) model. In the case of mixed order kinetics (MOK), the activation energy was analyzed as 2.29 eV. The activation energy was analyzed as 2.38 eV by the general order kinetics (GOK) model. In the case of LiF:Mg,Cu,P TLD, the activation energy was analyzed as 2.39 eV by result of the GAP model. In the case of MOK, the activation energy was analyzed as 2.55 eV. The activation energy was analyzed as 2.51 eV by the GOK model. The R value means different ratio of retrapping-recombination. The R value of LiF:Mg,Cu,Si TLD main peak analyzed as $1.12\times10^{-6}$ and $\alpha$ value analyzed as $1.0\times10^{-3}$. The R of LiF:Mg,Cu,P TLD analyzed as $7.91\times10^{-4}$, the $\alpha$ value means different ratio of initial thermally trapped electron density-initial trapped electron density (include thermally disconnected trap electrons density). The $\alpha$ value was analyzed as $9.17\times10^{-1}$ which was the difference from LiF:Mg,Cu,Si TLD. The deep trap electron density of LiF:Mg,Cu,Si was higher than the deep trap electron density of LiF:Mg,Cu,P.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.10
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• pp.37-44
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• 2018

In this study, the effects of considering hourly metabolic rate variations for predicted mean vote (PMV) control on the heating and cooling energy and greenhouse gas emission were investigated. The case adopting PMV control taking the hourly metabolic rate into account was comparatively analyzed against the conventional dry-bulb air temperature control, using a detailed simulation technique. Under the assumption that all the apartments in Korea adopt the PMV control incorporating real-time metabolic rate measurements, nationwide reductions of primary energy and greenhouse gas emission were analyzed. As a result, PMV control considering hourly metabolic rate variations is expected to reduce national primary energy by 6.2% compared to conventional dry-bulb air temperature control, corresponding to reduction of 10,342 GWh. In addition, it turned out that 6.6% of tCO2 emission can be reduced by adopting PMV control, corresponding to nationwide reduction of greenhouse gas emission by approximately 1,720,000 tCO2.

• The Journal of the Acoustical Society of Korea
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• v.29 no.3E
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• pp.131-139
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• 2010

This paper proposes a novel spectral hole substitution technique for low bit-rate audio coding. The spectral holes frequently occurring in relatively weak energy bands due to zero bit quantization result in severe quality degradation, especially for harmonic signals such as speech vowels. The enhanced aacPlus (EAAC) audio codec artificially adjusts the minimum signal-to-mask ratio (SMR) to reduce the number of spectral holes, but it still produces noisy sound. The proposed method selectively predicts the spectral shapes of hole bands using either intra-band correlation, i.e. harmonically related coefficients nearby or inter-band correlation, i.e. previous frames. For the bands that have low prediction gain, only the energy term is quantized and spectral shapes are replaced by pseudo random values in the decoding stage. To minimize perceptual distortion caused by spectral mismatching, the criterion of the just noticeable level difference (JNLD) and spectral similarity between original and predicted shapes are adopted for quantizing the energy term. Simulation results show that the proposed method implemented into the EAAC baseline coder significantly improves speech quality at low bit-rates while keeping equivalent quality for mixed and music contents.

• Journal of Nutrition and Health
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• v.43 no.1
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• pp.5-11
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• 2010

We conducted comparative study on metabolizable energy content of extracts of angelica keiskei and its byproduct. Total six different groups consisting of five test groups treated with angelica keiskei and one control group were compared. Each of the five test groups were given 30% of one of whole plant, extracts, fermented of extracts, byproduct and extracts plus byproduct, respectively, mixed with AIN93M. After 3 days of adjustment period, all groups were subjected to 4 days of test period during which the amounts of feed intake and excretion were measured everyday. All feces were treated for the prevention of decomposition and changes before its energy content were measured using a bomb calorimeter. The amount of excretion was $4.8\;{\pm}\;0.3\;g$/rat/3 days in control group and 9.9-15.0 g/rat/3 days in the groups were added with extracts of angelica keiskei indicating that the angelica keiskei-treated groups produce 2-3 times more excretion. Metabolic energy of control diet was 4,133.3 kcal. This was found to be 15 to 20% higher compared with the metabolic energy content ranging from 3,117.0 kcal/kg (extracts of angelica keiskei) to 3,259.8 kcal/kg (extracts plus byproducts) angelica keiskei-treated groups. This is interpreted as the result of the decreased metabolic energy in the test diets were substituted with 30% of ngelica keiskei-treated ingredient which has low metabolic content itself. One notable finding is that the metabolic content of the group mixed with byproducts and extracts (1,763.0 kcal/kg) is 27% higher than that of extracts of angelica keiskei (1,286.8 kcal/kg) indicating that mechanical grinding increases the rate of digestion and absorption increasing, in turn, the energy content used in the body. The results of analysis of overall caloric absorption showed absorption rate in order of Whole plant < extracts < byproduct < extract plus byproduct < fermented of extract.