• Title/Summary/Keyword: total energy

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An Application Analysis of Renewable Energy for Public Building and an Analysis of Building Energy Substitution Rate (공공건축물의 신재생에너지 적용분석 및 건물에너지 분담률 분석)

  • Kang, Su-Hyun;Yu, Si-Wan;Hwang, Jung-Ha;Cho, Young-Hum
    • 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.

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The Effects of Operational Conditions of Cooling Water System on Energy Consumption for Central Cooling System (냉각수 계통의 운전변수가 중앙냉방시스템의 에너지소비량에 미치는 영향)

  • Ahn, Byung-Cheon
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.13 no.4
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    • pp.8-13
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    • 2017
  • The effects of operational conditions of cooling water system on energy consumption for central cooling system are researched by using TRNSYS program. Cooling tower water pump flow rate, cooling tower fan flow rate, and condenser water temperature with various dry-bulb and wet-bulb temperatures are varied and their effects on total and component power consumption are studied. If the fan maximum flow rates of cooling tower is decreased, cooling tower fan and total power consumptions are increased. If the cooling tower water pump maximum flow rates is decreased, chiller and total power consumptions are increased. If condenser water set-point temperature is increased, chiller power consumption is increased and cooling tower fan power consumption is decreased, respectively.

Relationship between intake of energy and protein and permanent teeth caries (에너지 및 단백질 섭취와 영구치 우식과의 관련성)

  • Kim, Han-Na
    • Journal of Korean society of Dental Hygiene
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    • v.16 no.6
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    • pp.943-953
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    • 2016
  • Objectives: This study aims to evaluate the association between intake of energy, calcium and protein and permanent teeth caries in Korean children. Methods: Research data were obtained from the Fifth Korean National Health and Nutrition Examination Survey (KNHANES) and 1,274 Korean children within 9 to 12 years were selected as subjects for the study. The DMFT index, nutrition factors including total energy and protein intake, and degree of calcium intake were identified Chi-square test was performed to assess the difference of distribution in socioeconomic status, oral health behavior and nutrition factors according to sex. Multilevel linear regression analysis was performed to identify the relationship between DMFT index and the related variables. Results: Significant differences in energy, protein and Ca intake were confirmed according to the sex. Among 10 year-old children who intake total energy less than the recommended had few dental caries (p=0.058, ${\beta}=-0.411$). In addition, 11-year-old children having protein intake more than the recommended experienced dental caries (p=0.02, ${\beta}=0.588$). Conclusions: These results suggest that, there is significant differences between intake of energy and protein and dental caries among Korean children. However, further researches is needed to confirm between intake of energy and protein as a related factor.

Energy Flow and Bond Dissociation of Vibrationally Excited Toluene in Collisions with N2 and O2

  • Ree, Jongbaik;Kim, Sung Hee;Lee, Sang Kwon
    • Bulletin of the Korean Chemical Society
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    • v.34 no.5
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    • pp.1494-1502
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    • 2013
  • Energy flow and C-$H_{methyl}$ and C-$H_{ring}$ bond dissociations in vibrationally excited toluene in the collision with $N_2$ and $O_2$ have been studied by use of classical trajectory procedures. The energy lost by the vibrationally excited toluene upon collision is not large and it increases slowly with increasing total vibrational energy content between 5,000 and 45,000 $cm^{-1}$. Intermolecular energy transfer occurs via both of V-T and V-V transfers. Both of V-T and V-V transfers increase as the total vibrational energy of toluene increases. When the total energy content $E_T$ of toluene is sufficiently high, either C-H bond can dissociate. The C-$H_{methyl}$ dissociation probability is higher than the C-$H_{ring}$ dissociation probability, and that in the collision with $N_2$ is larger than with $O_2$.

Metabolic Components of Energy Expenditure in Growing Beef Cattle - Review -

  • Caton, J.S.;Bauer, M.L.;Hidari, H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.5
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    • pp.702-710
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    • 2000
  • A large portion of total energy expenditure associated with ruminant livestock production goes towards maintenance. Approximately 55% of whole body energy use is consumed by visceral tissues (including internal organs) with the majority of this going to the liver and gastrointestinal tract. Muscle and adipose tissues consume about 27% of total body energy expenditure. Metabolic components within the viscera responsible for the majority of energy consumption include ion transport, protein turnover, substrate cycling, and urea synthesis (liver). Within muscle tissue of growing animals ion transport and protein turnover account for most of the energy expenditure. Protein synthesis consumes approximately 23% of whole body energy use and visceral tissues account for proportionally more of whole body protein synthesis than skeletal muscle. Research efforts focused on improving energetic efficiency of the tissues and metabolic mechanisms responsible for the majority of whole animal energy expenditure should provide information leading to more efficient production of an edible product.

Optimization Application for Assessment of Total Transfer Capability Using Transient Energy Function in Interconnection Systems (과도에너지 함수를 이용하여 연계계통의 총송전용량 평가를 위한 최적화기법 응용)

  • Kim, Kyu-Ho;Kim, Soo-Nam;Rhee, Sang-Bong;Lee, Sang-Keun;Song, Kyung-Bin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.12
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    • pp.2311-2315
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    • 2009
  • This paper presents a method to apply energy margin for assesment of total transfer capability (TTC). In order to calculate energy margin, two values of the transient energy function have to be computed. The first value is transient energy that is the sum of kinetic and potential energy at the end of fault. The second is critical energy that is potential energy at controlling UEP(Unstable Equilibrium Point). It is seen that TTC level is determined by not only bus voltage magnitudes and line thermal limits but also transient stability. TTC assessment is compared by the repeated power flow(RPF) method and optimization method.

Conformational Studies of Sulfonylurea Herbicides : Bensulfuron Methyl and Metsulfuron Methyl

  • Young Kee Kang;Dae Whang Kim
    • Bulletin of the Korean Chemical Society
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    • v.11 no.2
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    • pp.144-149
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    • 1990
  • Conformational free energy calculations using an empirical potential function (ECEPP/2) and the hydration shell model were carried out on the sulfonylurea herbicides of bensulfuron methyl (Londax) and metsulfuron methyl (Ally). The conformational energy was minimized from starting conformations which included possible combinations of torsion angles in the molecule. The conformational entropy of each conformation was computed using a harmonic approximation. To understand the hydration effect on the conformation of the molecule in aqueous solution, the hydration free energy of each group was calculated and compared each other. It was found that the low-free-energy conformations of two molecules in aqueous solution prefer the overall folded structure, in which an interaction between the carbonyl group of ester in aryl ring and the first amido group of urea bridge plays an important role. From the analysis of total free energy, the hydration and conformational entropy are known to be essential in stabilizing low-free-energy conformations of Londax, whereas the conformational energy is proved to be a major contribution to the total free energy of low-free-energy conformations of Ally.

Decomposition of Direct and Indirect Energy Consumption Growth in Korea from 1990 to 2000 (한국 가정부문 직간접 에너지소비의 증가요인 분석: 1990~2000)

  • Park, Hi-Chun
    • Environmental and Resource Economics Review
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    • v.15 no.3
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    • pp.531-553
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    • 2006
  • As energy conservation can be realized through changes in the composition of goods and services consumed, there is a need to assess indirect and total household energy requirements. The Korean household sector was responsible for about 55% of the country's primary energy requirement in the period from 1990 to 2000. And more than 60% of household energy requirement was indirect. Thus, indirect and total rather than direct household energy requirements should be the target of energy conservation policies. Increases in household consumption expenditure were responsible for a relatively high growth of energy consumption. Switching to consumption of less energy intensive products and decrease in energy intensities of products contributed substantially to reduce the increase in total household energy requirement.

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Reinforcement Learning Based Energy Control Method for Smart Energy Buildings Integrated with V2G Station (강화학습 기반 V2G Station 연계형 스마트 에너지 빌딩 전력 제어 기법)

  • Seok-Min Choi;Sun-Yong Kim
    • The Journal of the Korea institute of electronic communication sciences
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    • v.19 no.3
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    • pp.515-522
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    • 2024
  • Energy consumption is steadily increasing, and buildings in particular account for more than 20% of the total energy consumption around the world. As an effort to cost-effectively manage the energy consumption of buildings, many research groups have recently focused on Smart Building Energy Management Systems (BEMS), which are deepening the research depth by applying artificial intelligence(AI). In this paper, we propose a reinforcement learning-based energy control method for smart energy buildings integrated with V2G station, which aims to reduce the total energy cost of the building. The results of performance evaluation based on the energy consumption data measured in the real-world building shows that the proposed method can gradually reduce the total energy costs of the building as the learning process progresses.

Process of Cost Estimation in Feasibility Analysis Considering ratio of Renewable Portfolio Standard (신·재생에너지 공급의무화제도(RPS) 비율을 고려한 타당성 분석의 공사비 산정 프로세스)

  • Yang, Hyun-Ju;Kim, Jong-Hyeob;Han, Sangwon;Hyun, Chang-Taek
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.44-45
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    • 2014
  • Recently the Korean government also has strictly restricted a law such as GBCC(Green Building Certification Criteria)and RPS(Renewable Portfolio Standard) on the construction. Especially the government announced a obligation of renewable energy consumption over 12% for all the public buildings of total area over 1,000㎡ since 2014. Regarding to the policy, this study presented the economics of energy analysis of the public office buildings that supplies 12% renewable energy output in the early stage of construction project. This paper calculated on CO2 emission by the geothermal, solar heat, and solar photovoltaic system and estimated the saving cost. Reduced cost through the energy saving are predicted to influence on the total construction cost. As a result air pollution and energy saving cost are expected that renewable energy system would be saving total initial cost of construction on planning phase.

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