• Asian-Australasian Journal of Animal Sciences
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• 제29권2호
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• pp.204-210
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• 2016

This study examined the effect of supplementing exogenous cellulase on nutrient and energy utilization. Twelve desexed Boer crossbred goats were used in a replicated $3{\times}3$ Latin square design with 23-d periods. Dietary treatments were basal diet (control, no cellulase), basal diet plus 2 g unitary cellulase/kg of total mixed ration dry matter (DM), and basal diet plus 2 g compound cellulase/kg of total mixed ration DM. Three stages of feeding trials were used corresponding to the three treatments, each comprised 23 d, with the first 14 d as the preliminary period and the following 9 d as formal trial period for metabolism trial. Total collection of feces and urine were conducted from the 4th d of the formal trial, and gas exchange measures were determined in indirect respiratory chambers in the last 3 d of the formal trial. Results showed that cellulase addition had no effect (p>0.05) on nutrient digestibility. Dietary supplementation of cellulase did not affect (p>0.05) N intake and retention in goats. Gross energy (GE) intake, fecal energy and urinary energy excretion, heat production were not affected (p>0.05) by the cellulase supplementation. Total methane emission (g/d), $CH_4$ emission as a proportion of live weight or feed intake (DM, organic matter [OM], digestible DM or digestible OM), or $CH_4$ energy output ($CH_4$-E) as a proportion of energy intake (GE, digestible energy, or metabolizable energy), were similar (p>0.05) among treatments. There was a significant (p<0.001) relationship between $CH_4$ and live weight (y = 0.645x+0.2, $R^2$ = 0.54), $CH_4$ and DM intake (y = 16.7x+1.4, $R^2$ = 0.51), $CH_4$ and OM intake (y = 18.8x+1.3, $R^2$ = 0.51) and $CH_4$-E and GE intake. Results from this study revealed that dietary supplementation of cellulase may have no effect on nutrient digestibility, nitrogen retention, energy metabolism, and methane emission in goat.

• Architectural research
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• 제22권1호
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• pp.13-21
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• 2020

The purpose of this study was to evaluate the variation in building energy predictions caused by simulation settings related to building envelop thickness. The study assessed the ceiling depth impact on skylight energy performance through OpenStudio integrated Radiance and EnergyPlus simulation programs. A ceiling as deep as 1.5 to 3m was analyzed for skylight to roof ratios from 1% to 25%. The results indicated that the building ceiling depth negatively affected the capability of skylights to significantly reduce building energy consumption. Through a parametric analysis, the study concluded that 8%, 9%, 10% and 11% skylight to roof ratio were optimal in terms of total building energy consumption for a ceiling depth of 1.5m, 2m, 2.5m and 3m, respectively. In addition, the results showed that the usually recommended 5% skylight to roof ratio was only efficient when no ceiling depth was included in the simulation model. Furthermore, the study indicated that the building energy saved by the optimal skylight of each ceiling depth decreased as the ceiling depth deepened. The highest total building energy reduction was 9%, 7%, 5% and 3% for a ceiling depth of 1.5m, 2m, 2.5m and 3m, respectively. This study induced that the solar heat gains and daylight visible transmittance by ceiling depth were crucial in the predictions of skylight energy performance and should not be neglected through building simulation simplifications as it is commonly done in most simulation programs' settings.

• KIEAE Journal
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• 제17권4호
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• pp.67-74
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• 2017

Purpose: As the recent climate environment changes so rapidly, environmental problems such as hot weather and fine dust have occurred, and interest in environmental policies and technology development is increasing in countries around the world. Similarly in the Architecture, researches to reduce greenhouse gas emissions and to reduce energy application are actively conducted. Looking at previous studies, it is analyzed that the electric VRF is more energy efficient than the gas engine VRF. However, energy costs have changed due to recent price hikes and discounts on gas charges due to high electricity consumption in summer. Method: In this study, the actual building of Gas Engine VRF system was modeled using SketchUp program, and EnergyPlus was used to simulate actual building. Also, Electric VRF system was simulated, and compared with Gas Engine VRF system. Result: The total secondary energy requirement of Electric VRF system was 19.6% less than that of the Gas Engine VRF system, But when analyzing with primary energy requirement, EHP used 15.8% more energy. CO2 emissions were also estimated to be 16.9% more EHP. Energy costs were 14.8% more in Electric VRF systems, because their electricity charges are 0.6 to 160% more expensive than gas charges.

• 한국태양에너지학회 논문집
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• 제34권1호
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• pp.8-18
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• 2014

Building simulation is used in a variety of sectors. In its early years, building simulation was mainly used in the design phase of a building for basic functions. Recently, however, it has become increasingly important during the operating phase, for commissioning and facility management. Most building simulation tools are used to estimate the thermal environment and energy consumption performance, and hence, they require the inputting of hourly weather data. A building simulation used for prediction should take into account the use of standard weather data. Weather data, which is used as input for a building simulation, plays a crucial role in the prediction performance, and hence, the selection of appropriate weather data is considered highly important. The present study proposed a technique for generating real-time weather data files, as opposed to the standard weather data files, which are required for running the building simulation. The forecasted weather elements provided by the Korea Meteorological Administration (KMA), the elements produced by the calculations, those utilizing the built-in functions of Energy Plus, and those that use standard values are combined for hourly input. The real-time weather data files generated using the technique proposed in the present study have been validated to compare with measured data and simulated data via EnergyPlus. The results of the present study are expected to increase the prediction accuracy of building control simulation results in the future.

• 한국태양에너지학회 논문집
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• 제30권6호
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• pp.1-9
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• 2010

Apartment balcony has been remodeled since the government permitted remodeling in January 2006.But extended balcony has great impact on building heat gain and loss. Therefore It has problems such as increase of heating and cooling energy. So $\underline{t}echnical$ solutions about window solar gain in summer is an urgent matter. The Purpose of this study is to evaluate energy performance of a blind in a double-skin facade in residential buildings by using EnergyPlus program. The results show that slat angles of $90^{\circ}$ is best in energy performance if we do not consider daylight. Poorly daylighted living room needs electric light and it also causes high cooling load. On the other hand, the results show that the application of blinds controlled automatically is best for energy performance when we consider daylight. Blind slat angles of $50\sim60^{\circ}$ have best performance when blinds are controlled in this angle throughout the day on a clear day in August. Blind slat angles of $0\sim30^{\circ}$ have best performance when blinds $\underline{are\;controlled}$ in this angle throughout the day on a cloudy day (more than 7 of total sky cover) in August.

• 융합정보논문지
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• 제9권1호
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• pp.54-60
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• 2019

최근 기후변화로 인한 외부 열환경이 악화되고 있으며, 이로인한 건축물에너지사용량이 상승하고 있다. 기후변화 대응형 건축물 저에너지 기술 성능평가를 위하여 Energy Plus를 활용하였다. 실험군 유형은 기본건축물(Control)과 기화냉각시스템(EMS)이며, 유형별 분석결과를 비교하였다. 에너지성능평가결과 냉방피크부하는 Control 대비 EMS에서 약 9% 이상 저감률을 보였다. 단위면적당 연간 냉방부하는 Control 대비 EMS에서 약 17% 이상 저감률을 나타내었다. 단위면적당 연간 에너지사용량은 Control 대비 EMS에서 약 10% 이상 저감률을 보였다. 따라서 건축물 에너지저감기술로 기화냉각시스템의 효과는 양호한 것으로 판단되었으며, 향후 기화냉각시스템의 분사량 및 이격거리에 따른 건축물에너지성능평가 연구가 진행되어야 할 것이다.

• Journal of Nutrition and Health
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• 제43권1호
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• pp.5-11
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• 2010

본 연구는 명일엽과 그 가공산물의 대사에너지 함량을 분석하기 위해 실시하였다. 명일엽 전초, 명일엽 녹즙, 녹즙박, 발효녹즙 및 녹즙 + 녹즙박 5가지 식품을 기초식이에 30% 첨가하여 실험식이를 제조하였다. 기초식이는 AIN93M을 사용하였다. 실험용 쥐는 실험군당 6마리를 사용하였고, 3일간 실험식이에 적응시킨후 4일간 식이섭취량을 측정하고 분과 뇨를 모두 수거하였다. 수거한 분과 뇨는 bomb calorimeter로 gross energy를 측정하였다. 본 연구결과, 명일엽 가공산물의 대사에너지 함량은 명일엽 1,286.8 kcal/kg, 명일엽 녹즙 1,642.6 kcal/kg, 발효녹즙 2,044.8 kcal/kg, 녹즙박 1,687.5 kacl/kg, 명일엽 녹즙 + 녹즙박 1,763.0 kcal/kg이었다. 수분을 함유한 원물은 각각 193, 82, 102, 270 및 216 kcal/kg이었다. 이를 여러 에너지환산계수를 이용한 에너지가와 비교한 결과 20~60% 차이를 보였다. 특히 원물에서 명일엽은 식품성분표에서는 340 kcal/kg의 열량가를 갖는 것으로 발표되었지만, 동물을 이용한 대사에너지 측정치는 193 kcal/kg으로 76% 낮게 나타났다. 이는 섬유소 함량이 높은 명일엽과 가공 산물들은 실험동물을 이용한 방법이 energy conversion factor로 계산한 수치보다 정확한 대사에너지 함량을 구하기에 더 적합하기 때문으로 판단된다.

• Applied Biological Chemistry
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• 제8권
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• pp.21-28
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• 1967

등량(等量)의 사료(飼料)로서 급식회수(給食回數)를 달리 했을때 면양(緬羊)의 증체(增體), 영양소(營養素)의 소화율(消化率), 열량이용성(熱量利用性), 체조직(體組織)의 화학성분(化學成分)에 미치는 영향(影響)을 연구(硏究)하기 위하여 32두(頭)의 면양(緬羊)으로 두개(個)의 실험(實驗)을 하였든바 그 성적(成績)은 다음과 같다. (1) 영양소(營養素)의 소화율(消化率) 및 ME가(價)에 있어서 1 일(日) 1회(回) 8급식구(給食區), 1 일(日) 8회급식구(回給食區), 1 일(日) 1회급식(回給食)+7회첨수구(回添水區)사이에 하등(何等)의 차이(差異)가 발견(發見)되지 않았다. (2) 매대사체중당(每代射體重當) 열발생량(熱發生量)은 1 일(日) 8회구(回區)가 1회구(回區)보다 훨씬 적었다. (3) 1 일(日) 8회구(回區)보다 증체량(增體量)이 더 많았다. (4) 1 일(日) 8회구(回區)의 경우 체단백질(體蛋白質), 지방(脂肪), 에너지의 증가(增加)가 1회구(回區)보다 훨씬 왕성하였다. (5) 증체(增體)된 부분(部分)의 체조성(體組成) 변화(變化)를 보면 1회구(回區)의 경우에 훨씬 많은 량(量)의 지방(脂肪), 단백질(蛋白質), 광물질(鑛物質)이 비축되었다. (6) 급식회수(給食回數)가 위에서 본바와 같은 영향을 일으키는 생리적기전(生理的機轉)의 일부(一部)가 설명(說明)되었다.

• 한국환경과학회지
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• 제23권8호
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• pp.1437-1446
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• 2014

This study, the urban energy used office building green roof type composition of the target by analyze building energy reductions. Green roof is total 6 types(type A~F) were selected, EnergyPlus the energy simulation programs were used. Top floor of green roof types evaluation, the reduction of the cooling peak load type E(1.26%), type D(1.30%), type C(1.37%), type B(1.45%), type F(1.49%), and heating peak load is type D(1.32%), type E(1.40%), type C(1.47%), type F(1.69%), type B(2.13%) order. Annual cooling load of heating load is reduced more than about 1% effect. The heating load reduction ratio for a maximum of 9% respectively. Cooling peak load of the building energy performance evaluation of type F > type B > type C > type D > type E in the order and in the case of peak loads heating type B > type F > type D > type E>type C order. Annual total energy use reduction of 1.07 to 1.22% and earn, type B in the best good. In primary energy use reductions in the presence of a green roof were in the 4249~4876 kWh/yr. Annual $CO_2$ emissions reductions of unapplied type A were analyzed on average 469.78 kg.

• 한국수소및신에너지학회논문집
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• 제24권3호
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• pp.249-254
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• 2013

The integrated gasification combined cycle (IGCC) system is well known for its high efficiency compared with other coal fueled power generation system. The aim of this study is to confirm the feasibility of using bio gas in coal feeding system and syngas recirculation system. The effects of using bio gas in the gasifier on the syngas composition were investigated through simulations using the Aspen Plus process simulator. It was found that these changes had an influence on the syngas composition of the final stream and bio gas can be used in a gasifier system.