• Title/Summary/Keyword: proportion of energy

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Seismic energy dissipation in torsionally responding building systems

  • Correnza, J.C.;Hutchinson, G.L.;Chandler, A.M.
    • Structural Engineering and Mechanics
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    • v.3 no.3
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    • pp.255-272
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    • 1995
  • The paper considers aspects of the energy dissipation response of selected realistic forms of torsionally balanced and torsionally unbalanced building systems, responding to an ensemble of strong-motion earthquake records. Focus is placed on the proportion of the input seismic energy which is dissipated hysteretically, and the distribution of this energy amongst the various lateral load-resisting structural elements. Systems considered comprise those in which torsional effects are discounted in the design, and systems designed for torsion by typical code-defined procedures as incorporated in the New Zealand seismic standard. It is concluded that torsional response has a fundamentally significant influence on the energy dissipation demand of the critical edge elements, and that therefore the allocation of appropriate levels of yielding strength to these elements is a paramount design consideration. Finally, it is suggested that energy-based response parameters be developed in order to assist evaluations of the effectiveness of code torsional provisions in controlling damage to key structural elements in severe earthquakes.

Research on the Energy Hole Problem Based on Non-uniform Node Distribution for Wireless Sensor Networks

  • Liu, Tang;Peng, Jian;Wang, Xiao-Fen;Yang, Jin;Guo, Bing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.9
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    • pp.2017-2036
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    • 2012
  • Based on the current solutions to the problem of energy hole, this paper proposed a nonuniform node distribution clustering algorithm, NNDC. Firstly, we divide the network into rings, and then have an analysis and calculation on nodes' energy consumption in each ring of the network when clustering algorithm is applied to collect data. We also put forward a scheme of nonuniform node distribution on the basis of the proportion of nodes' energy consumption in each ring, and change nodes' active/hibernating states under density control mechanism when network coverage is guaranteed. Simulation shows NNDC algorithm can satisfyingly balance nodes' energy consumption and effectively avoid the problem of energy hole.

A basic study for the development of energy conservation web education programs -focused on the lighting energy (에너지 절약 웹 교육 프로그램 개발을 위한 기초 연구 -조명 에너지 중심으로)

  • Kim, Na-Young;Chang, Soo-Jung;Choi, An-Seop;Chun, Jung-Yun
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.200-204
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    • 2004
  • It is a global consent that we should conserve our energy consumption, due to our awareness to the environmental problems and the limitedness of the natural resource. In the country, the level of energy consumption is more than it is needed, according to its living standard and the proportion of resources imported from other countries. Educational program focused on energy conservation is essential to overcome these problems. This paper outlines a basic study on the development of an energy conservation education program for children. This program makes students aware of the importance and difficulties in energy conservation. The students can then make their own contribution and besides circulation of resources and improvement of health problems.

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Determining the Optimal Capacities of Distributed Generators Installed in A Stand-alone Microgrid Power System (독립형 마이크로그리드 내 분산전원별 최적용량 결정 방법)

  • Ko, Eun-Young;Baek, Ja-Hyun;Kang, Tae-Hyuk;Han, Dong-Hwa;Cho, Soo-Hwan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.2
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    • pp.239-246
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    • 2016
  • In recent years, the power demand has been increasing steadily and the occurrence of maximum power demand has been moving from the summer season to the winter season in Korea. And since the control of electric power supply and demand is more important under those situations, a micro-grid system began to emerge as a keyword for the sTable operation of electric power system. A micro-gird power system is composed of various kinds of distributed generators(DG) such as small diesel generator, wind turbine, photo-voltaic generator and energy storage system(ESS). This paper introduces a method to determine the optimal capacities of the distributed generators which are installed in a stand-alone type of microgrid power system based on the fundamental proportion of diesel generator. At first, the fundamental proportion of diesel generator will be determined by changing from 0 to 50 percent. And then we will optimize the capacities of renewable energy resources and ESS according to load patterns. Lastly, after recalculating the capacity of ESS with consideration for SOC constraints, the optimal capacities of distributed generators will be decided.

Effects of Dietary L-Carnitine and Protein Level on Plasma Carnitine, Energy and Carnitine Balance, and Carnitine Biosynthesis of 20 kg Pigs

  • Heo, K.N.;Odle, J.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.11
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    • pp.1568-1575
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    • 2000
  • Growing pigs (N=25; 18 kg) were used to study effects of L-carnitine and protein intake on plasma carnitine, energy and carnitine balance, and carnitine biosynthesis. Corn-soybean meal basal diets containing low or high protein (13.6% or 18%) were formulated so that protein accretion would be limited by metabolizable energy (ME). Each basal diet was supplemented with 0 or 500 mg/kg L-carnitine and limit fed to pigs for 10 d in a balance trial. Final carnitine concentration was compared with weight/age matched pigs measured on d 0 to calculate carnitine retention rates. Supplementation of carnitine increased (p<0.01) plasma free carnitine (by 250%), short-chain (by 160%) and long-chain acyl-carnitine concentrations (by 80%) irrespective of blood sampling time (p<0.01). The proportion of long-chain carnitine esters decreased by 40% (p<0.01) by carnitine supplementation; whereas, the proportion of short-chain acyl-carnitine concentration was not changed (p>0.10). All criteria of energy balance were unaffected by L-carnitine (p>0.10). Total body carnitine retention was increased by 450% over unsupplemented controls (p<0.01). Carnitine biosynthesis rates in pigs fed diets without L-carnitine were estimated at 6.71 and $10.63{\mu}mol{\cdot}kg^{-1}{\cdot}d^{-1}$ in low protein and high protein groups, respectively. In supplemented pigs, L-carnitine absorption and degradation in the intestinal tract was estimated at 30-40% and 60-70% of L-carnitine intake, respectively. High protein feeding effect did not affected plasma carnitine concentrations, carnitine biosynthesis or carnitine retention (p>0.10). We conclude that endogenous carnitine biosynthesis may be adequate to maintain sufficient tissue levels during growth, but that supplemental dietary carnitine (at 500 ppm) sufficiently increased plasma acyl-carnitine and total body carnitine.

Evaluation of Dietary Habits and Health-Related Factors According to the Employment in Women in Early Adulthood - Based on the 2016~2019 Korea National Health and Nutrition Examination Survey (20대 성인 여성에서 정규직 여부에 따른 식생활 및 건강 관련 요인 분석 연구 - 2016~2019년 국민건강영양조사 자료를 이용하여 -)

  • Bae, Yun-Jung
    • Korean Journal of Community Nutrition
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    • v.26 no.4
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    • pp.249-258
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    • 2021
  • Objectives: This study aimed to compare the factors of dietary and health behavior according to the employment in women in early adulthood and to analyze their relationship. Methods: In this study, adult women aged 20~29 who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) 2016~2019 were classified into two groups depending on their permanent worker status, namely tenured employees (n = 254) and temporary employees (n = 377). Dietary habits (prevalence of skipping meals, food nutrition label use, etc.), nutrient intake, and metabolic syndrome factors were analyzed. Results: The tenured employees' group showed a significantly lower proportion of subjects who skipped breakfast (P = 0.0254) and significantly higher daily energy intake (P = 0.0264) than the temporary employees' group. However, there were no significant differences in the intake of energy nutrients and most of the micronutrients per 1,000 kcal of energy intake between the two groups. The proportion of subjects who consumed energy nutrients under 75% of the estimated energy requirement (EER) was 38.11% in the tenured employees' group, which was significantly lower than the 48.30% in the temporary employees' group (P = 0.0159). In economically active women aged 19~29 years, the odds ratio of low HDL-cholesterolemia prevalence was 1.80 times higher (95% CI, 1.06-3.06) in the temporary employees' group compared to that in the tenured employees' group after adjustment for confounding factors (P = 0.0295). Conclusions: In conclusion, among Korean adult women in their twenties, temporary employees showed inappropriate eating habits such as skipping breakfast, and had abnormal blood lipid levels.

Key Technologies for Stabilization of Power System for Successful Achievement of 3020 Renewable Energy Policy (3020신재생에너지 정책의 성공적 달성을 위한 전력계통 안정화 핵심기술 개발 방향)

  • Kim, Hun-Tae;Jhang, Seong-Su
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.2
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    • pp.149-157
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    • 2018
  • Recently, because Korean government's 3020 renewable energy policy is implemented, renewable energy sources are connected in the power system. The power quality of the Korean power system has been maintained at the highest level in the world, but it will become difficult to maintain the highest level of power quality as the proportion of renewable energy source, which is characterized by severe output fluctuation and difficult control, increases. For those reasons, this paper analyzed Key technologies for stabilization of power system.

A Study on Energy expenditure in Korean Adult (한국인의 에너지 소비량에 관한 연구)

  • 오승호
    • Journal of Nutrition and Health
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    • v.22 no.6
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    • pp.423-437
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    • 1989
  • A 4-week energy balance study was conducted to estimate the energy expenditure (EE) of 16 college age men and women, 20 to 26 year of age, by measurement of energy intakes and changes in body energy(BE) content(intake/balance technique), keeping their normal living pattern and maintenance body weight. Energy intake was measured by bomb calorimetry and estimated by food table. Fecal energy loss was calculated from nitrogen excreted. Fat mass was determined from body density estimated from skinfold tickness. 1) Gross energy (GE) intakes calculated from food table was not only 13.4% lower than those of bomb calorimetry but also lower 4 and 5% than metabolizable energy(ME) intakes for the male and female subjects, respectively. 2) Fecal energy loss was 7.2% and 6.9% proportion of the gross energy intake for the male and female subjects, respectively. 3) Mean daily metabolizable energy intakes estimated by subtract fecal and urinary energy loss was 2467kcal for the male subjects and 1897kcal for the female subjects. 4) Total body energy change estimated from body composition change over 31 days was decreased 7672kcal for the male subjects and 2689kcal for the female subjects. 5) Mean daily energy expenditure was 2714kcal (45kcal/kg of body weight) for the male subjects and 1984kcal(40kcal/kg of body weight) for the female subjects. 6) The estimated energy expenditure of college-age subjects in this study provide evidence to support the Recommended Dietary Allowances for energy of Korean normal adult.

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A Study on the Institutionalization of Energy Efficient Operation and Maintenance Program for Existing Buildings (기존 건축물의 운영단계 에너지효율 개선을 위한 관리 및 제도화 방안 연구)

  • Cho, Jinkyun;Lee, Youngjae
    • Journal of the Korean Solar Energy Society
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    • v.40 no.3
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    • pp.33-42
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    • 2020
  • Operational energy is the energy that is used during the occupancy stage of building life cycle. It is associated with relatively longer proportion of infrastructure's service life and can constitute 80-90% of the total energy. Assessing the energy use in buildings is essential since they are significant contributors to energy demand. In this regard, energy performance of buildings has become the focus of many regulations. This paper aimed to review the regulations about the energy performance of buildings during their operational stage in Korea. For energy efficient operation program for existing buildings, governments should implement policies and support voluntary programs that rely on collecting and managing building performance data and using this data to inform public and private-sector operation and maintenance strategies. Implementing these policies and programs requires tools and processes for collecting, curating, managing, analyzing, and publishing this data. Energy assessment tool, that is a data resource management tool that enables to assess energy use across the entire portfolio of buildings, is also required.

Study on Energy Consumption according to Building Envelope Performance and Indoor Temperature (건축물의 외피성능 및 실내온도에 따른 에너지 사용량에 관한 연구)

  • Yoo, Ho-Chun;Kang, Hyun-Gu
    • Journal of the Korean Solar Energy Society
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    • v.31 no.3
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    • pp.101-108
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    • 2011
  • This study aims to suggest an energy consumption improvement plan for university buildings through an analysis of energy consumption. Upon a simulation of subject building to interpret energy consumption, it was found that 154.07kWh/$m^2$ of energy is consumpted annually. Improvement of design elements can cut down the energy consumption to 135.61kWh/$m^2$ according to an energy reduction analysis related to envelope performance improvement. Additional improvement of lights and heat exchanger can curtail annual energy consumption to 108.32kWh/$m^2$. Also, an analysis of energy consumption while increasing indoor temperature gradually showed that the two factors are in proportion. $6^{\circ}C$ higher temperature requires over twice of the current energy. Based on this survey result, performance improvement due to building management and envelope elements which influence to building cooling and heating loads can curtail building energy consumption.