• 제목/요약/키워드: energy direction

검색결과 2,130건 처리시간 0.032초

에너지 저장시스템의 효율성 검토 및 정책 분석 (An Analysis of Efficiency and Government Policies of ESS)

  • 김범곤;이승철;김철환;이시빈
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.2373-2382
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    • 2011
  • As the government set the direction for Green Growth recently, so local government struggles to obtain carbon emissions trading. In the center of this global environment atmosphere, the quantitative targets would be suggested by some developed countries. In case of a international green movement like this, it would have been being induced from by crystallizing of economic and environmental regulations and legal policies that not only a meter-rate system of carbon emissions but also application for regenerate energy. In this paper, we researched cultivating of energy storage system(ESS) to conjugate regenerative energy of train, an energy efficiency and cultivating cost etc. In conclusion, we would acknowledge a difficulty in cultivating ESS only for cost reduction of energy consumption, so governmental policies for green growth should be thoughtfully examined.

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층간분리된 복합적층판의 에너지 방출률에 관한 연구 (A Study on the Energy Release Rate of Delaminated Composite Laminates)

  • 정성균
    • 한국자동차공학회논문집
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    • 제3권1호
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    • pp.97-107
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    • 1995
  • Global postbuckling analysis is accomplished for one-dimensional and two-dimensional delaminations. A new finite element model, which can be used to model the global postbuckling analysis of one-dimensional and two-dimensional delaminations, is presented. In order to calculate the strain energy release rate, geometrically nonlinear analysis is accomplished, and the incremental crack closure technique is introduced. To check the effectiveness of the finite element models and the incremental crack closure technique, the simplified closed-form sloution for a through-the-width delamination with plane strain condition is derived and compared with the finite element result. The finite element results show good agreement with the closed-foul1 solutions. The present method was extended to calculate the strain energy release rate for two-dimensional delamination. For a symmetric circular delamination, the strain energy release rate shows great variation along the delamination front. and the delamination growth appears to occur perpendicular to the loading direction.

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Analysis on the Circumference Wall Temperature in a Long Horizontal Pipe with Thermal Stratification

  • Ahn, Jang-Sun;Ko, Yong-Sang;Kim, Yu-Hwan;Park, Byeong-Ho;Kim, Eun-Kee
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1995년도 추계학술발표회논문집(1)
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    • pp.364-370
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    • 1995
  • The One-dimensional fin model is used to analyze the angular wall temperature variation of long horizontal lines, where stratification could result in top-to-bottom differences in wall temperatures. The top and bottom sections are treated separately and coupled by boundary conditions. The thermal stratification analysis is focused on the effects of the heat transfer rates at the pipe surface. The results show that the heat transfer rate at the pipe surface is the controlling parameter which reduce significantly the temperature difference in pipe circumferential direction. The one-dimensional fin modelling analysis results are verified by comparison with the operating PWR test data. The circumferential temperatures of pipe calculated by one-dimensional fin modelling agree well with the PWR plant test data.

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가스 엔진용 1kW급 계통 연계 영구자석형 동기발전기 구동 시스템 설계 (Design of Control System for 1kW Grid-connected Permanent Magnet Synchronous Generator)

  • 이태영;조영훈
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2017년도 추계학술대회
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    • pp.69-70
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    • 2017
  • This paper presents design of control system for permanent magnet synchronous generator(PMSG). The gas engine make rotating mechanical energy from gas fuel energy. The rotor of synchronous generator is connected to axis of engine. And it converts the mechanical energy to the electrical energy. The control system of PMSG helps the electrical energy to flow to grid. the single phase pfc rectifier controls the DC-link voltage by controlling the current of filter inductor. If the DC-link voltage is higher than the voltage reference, the filter current could be controlled to flow to grid. The three phase inverter controls the stator current of generator. The direction of the current is controlled depends on motoring or generating mode. The feasibility of the grid-connected PMSG is verified by the experimental results with 1kW prototype.

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A New Method for Measuring Azimuthal Anchoring Energy of Rubbed and UV-Exposed Polyimide Alignment Layers

  • Park, H.J.;Lee, W.K.;Kim, D.G.;Shin, D.C.;Woo, J.W.;Shin, H.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1619-1621
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    • 2007
  • Novel optical measurement systems and improved cell configurations for measuring of azimuthal anchoring energies were developed. The difference between the mechanical rubbing direction and the optical easy axis that caused errors in the previous azimuthal anchoring energy measurement was compensated. In addition, the measurement accuracy of the twist angle and therefore the azimuthal anchoring energy was greatly enhanced. As a result, we were able to obtain valid azimuthal anchoring energy values for different alignment layers.

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Hydraulic Model Test of a Floating Wave Energy Converter with a Cross-flow Turbine

  • Kim, Sangyoon;Kim, Byungha;Wata, Joji;Lee, Young-Ho
    • International Journal of Fluid Machinery and Systems
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    • 제9권3호
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    • pp.222-228
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    • 2016
  • Almost 70% of the earth is covered by the ocean. Extracting the power available in the ocean using a wave energy converter has been seen to be eco-friendly and renewable. This study focuses on developing a method for analyzing a wave energy device that uses a cross-flow turbine. The motion of the ocean wave causes an internal bi-directional flow of water and the cross-flow turbine is able to rotate in one direction. This device is considered of double-hull structure, and because of this structure, sea water does not come into contact with theturbine. Due to this, the problem of befouling on the turbine is avoided. This study shows specific relationship for wave length and several motions.

초음파를 이용한 두꺼운 복합재료의 보강섬유 굴곡 평가 (Nondestructive Evaluation of Fiber Waviness in Thick Composites by Ultrasonics)

  • 장필성;전흥재
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 1999년도 추계학술발표대회 논문집
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    • pp.258-263
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    • 1999
  • In this study, the numerical and experimental investigations were conducted to understand ultrasonic wave propagation and to evaluate the degree of fiber waviness in thick composites nondestructively. The path, energy and traveling time of insonified wave were predicted by adopting the ray and plane wave theories. In the analysis, the composites were assumed to have continuous fiber with sinusoidal waviness in a matrix and were modeled as stacks of infinitesimally short length off-axis elements with varying fiber orientation along the length direction. From the experiments on the specially fabricated thick composite specimens with various degrees of uniform fiber waviness, the energy distributions of received wave were obtain for the various positions of transmitter. It was observed that the energy of wave was converged to the adjacent peaks of fiber waviness. The location where maximum energy of wave was detected from the experiments showed good agreement with the location obtained from theoretical predictions. Finally, the test procedure was Proposed to evaluate fiber waviness in thick composites by considering the energy of wave and relative distance between transmitter and receiver.

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G-SEED 개선을 위한 패시브디자인 적용현황 분석 (Analysis of the Passive Design Application Status for the Improvement of G-SEED)

  • 김혜원;태춘섭;김준태
    • 한국태양에너지학회 논문집
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    • 제35권6호
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    • pp.35-42
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    • 2015
  • The proper use of the passive and active design elements are important for the realization of green buildings. The G-SEED (Green Standard for Energy and Environmental Design) has been implemented in Korea to promote green building construction reflecting these design elements. In this paper, evaluation items of G-SEED which related to the passive design were selected. And improvement direction for the G-SEED was proposed through the analysis of the application status of the passive design elements for the G-SEED certified buildings. This results can be used for developing study on the future improvement of the assessment criteria of G-SEED.

유리성능에 따른 커튼월건물의 에너지절약효과에 대한 연구 -표준건물 에너지소비와의 비교분석을 중심으로- (A Study on a Efficiency of Glazing for Energy Reduction of Curtain Wall Buildings)

  • 이용준;정광섭;오보환;강재식;최경석;이득호
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2009년도 하계학술발표대회 논문집
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    • pp.114-119
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    • 2009
  • This study has been conducted to describe the establishment of national measures to reduce world energy consumption and $CO_2$ Emission. Particularly, Reductions in energy consumption from building operation is the most important part to achieve these national objectives. Element to evaluate the quantitative effects of these systems by having rationalized regulation and operation is essential, when planning for building energy reduction design. USGBC(US Green Building Council) have operated sustainable assessment method called LEED, which introduces baseline performance and evaluation direction for building simulation techniques. This research analyzed Quantitative assessments of the building energy consumption and analyzed baseline figures to provide comparative analysis with standard building settings.

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Error Analysis of Measure-Correlate-Predict Methods for Long-Term Correction of Wind Data

  • ;김현구;서현수
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
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    • pp.278-281
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    • 2008
  • In these days the installation of wind turbines or wind parks includes a high financial risk. So for the planning and the constructing of wind farms, long-term data of wind speed and wind direction is required. However, in most cases only few data are available at the designated places. Traditional Measure-Correlate-Predict (MCP) can extend this data by using data of nearby meteorological stations. But also Neural Networks can create such long-term predictions. The key issue of this paper is to demonstrate the possibility and the quality of predictions using Neural Networks. Thereto this paper compares the results of different MCP Models and Neural Networks for creating long-term data with various indexes.

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