• 제목/요약/키워드: Field Environment

검색결과 8,421건 처리시간 0.031초

고속전차선로 유리애자 현장 적합성 기반 구축 연구 (Base data establishment of suitability for Toughened Glass Stem Insulator applied in the high speed catenary system)

  • 전용주;류영태;이태훈;박기범;이기천;김선구
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 추계학술대회 논문집
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    • pp.140-143
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    • 2008
  • The Operation of high speed train in year 2004 bring about a great change in railroad industry. Especially in railroad construction field we have acquired great Know-how. And up to now we are building up operation skills. But the high speed train system are totally imported, so it is necessary to investigate some of the equipment based on our own environment. In case of Toughened Glass Stem Insulator, we don't have any application case in domestic and limited in abroad. So there must be some characteristic estimation. This paper introduces estimation methode in three different field. First electrical field, Second physical field and finally environment circumstance. In Electrical field, amplitude and number of time for abnormal peak voltage data are collected. And in physical field case, amplitude and trend of vibration in to the insulator are examined. And I circumstance case, possibility of flying gravel and ice clod are investigated. Through this basic data, suitability for Toughened Glass Stem Insulator using in domestic will be accumulated and estimated.

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남한지역 풍력자원 평가 및 바람지도 구축을 위한 바람권역 분류 (Classification of Wind Sector for Assessment of Wind Resource and Establishment of a Wind Map in South Korea)

  • 정우식;이화운;박종길;김현구;김은별;최현정;김동혁;김민정
    • 한국환경과학회지
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    • 제18권8호
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    • pp.899-910
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    • 2009
  • We classified wind sectors according to the wind features in South Korea. In order to get the information of wind speed and wind direction, we used and improved on the atmospheric numerical model. We made use of detailed topographical data such as terrain height data of an interval of 3 seconds and landuse data produced at ministry of environment, Republic of Korea. The result of simulated wind field was improved. We carried out the cluster analysis to classify the wind sectors using the K-means clustering. South Korea was classified as 8 wind sectors to the annual wind field.

실측 분석기법과 시뮬레이션 분석 기법에 의한 아트리움 열환경 개선에 관한 연구 (A Study on the Improvement of Thermal Environment by a method using thermometers and computer simulations on the Atrium)

  • 이소연;안정수;김강수
    • 한국태양에너지학회 논문집
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    • 제29권5호
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    • pp.28-34
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    • 2009
  • The atrium in the building has many advantages including its aesthetic and functional effect. But the upper part of the atrium has the thermal problem of overheating due to insolation through the window. But natural ventilation aided buoyancy effect can be a solution to make comfortable indoor environment. Proper design of openings is very important to improve thermal environment in the atrium. In this study, thermal evaluations were performed to improve thermal environment in the atrium. Indoor thermal environment of an atrium at Seoul was measured in the field and simulated with Computational Fluid Dynamics( CFD) code. The turbulent flow model adopted is $K-{\varepsilon}$ model. The results of computer simulations are compared with the measurements at the point in the atrium. In order to improve the indoor ventilation environment of the atrium, thermal environment evaluations of six alternatives were conducted. After evaluations of the results, the design guidelines of an atrium are suggested.

일차원 적운모델을 이용한 산성강우 형성에 관한 수치적 연구 (Numerical Studies of Cloud Acidification Processes Using a One Dimensional Cumulus Cloud Model)

  • 곽노혁;안상욱;홍민선
    • 한국대기환경학회지
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    • 제7권3호
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    • pp.145-149
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    • 1991
  • A one dimensiional cumulus cloud model has been developed for the investigation of temporal and altitudinal variation of trace gases and the wet deposition rates of sulfate for different simulation conditions. The results show that the dynamic field, liquid mixing ratios and the solubility of trace gases affect the distribution of trace gases and the droplet pH. Temporal variation of the predicted surface precipitation and sulfate deposition rates agree well with the field data.

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The Effect of an External Electric Field on Phase Separation, Phase Dissolution, and Isothermal Crystallization Behavior of Poly(vinylidene fluoride)/Poly(1,4-butylene adipate) Blends

  • Kim, Kap-Jin;Lee, Jong-Soon
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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    • pp.7-8
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    • 2003
  • Since PVDF/poly(1,4-butylene adipate) blend shows much lower LCST curve compared with PVDF/PMMA blend, the PVDF/PBA blend can be a good candidate for investigating the effect of the electric field on the phase separation and dissolution behavior of an electro-active polymer and electro-inactive polymer blend. (omitted)

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The Fundamental Requirements in the Application of Relaxed Eddy Accumulation Method for Measuring the Trace Gas Fluxes

  • Kim Ki-Hyun
    • Journal of Korean Society for Atmospheric Environment
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    • 제21권E1호
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    • pp.37-39
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    • 2005
  • It is well perceived that micrometeorological approach is one of the most reliable method for the quantification of vertical fluxes of trace components in the atmosphere. In this study, the feasibility of relaxed eddy accumulation (REA) method is discussed with respect to its reliability in the field application. Knowing that the use of micrometeorological approaches requires validation of analytical uncertainties involved, the problems and issues associated with its application are discussed to stimulate the proper employment of such technique in the field study.

Study of statistical distribution for four-port TEM cell

  • Jeon, Sangbong;Kwon, Jong-Hwa
    • Journal of Multimedia Information System
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    • 제1권2호
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    • pp.127-132
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    • 2014
  • The transverse electromagnetic (TEM) cells are widely used for electromagnetic compatibility (EMC) testing and field probe calibrations. We propose the verification of TEM mode with statistical method using a four-port TEM cell. The verification results are compared with Normal, Rayleigh, and Gamma distribution. As a result, the 75 % quantile of the Rayleigh distribution is excellent agreement with the true quantiles for a number of calibration points.

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현장 토양 투수계수 측정: 방법 및 사례

  • 이진용;이명재;최예권;김용철;이강근
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 추계학술발표회
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    • pp.188-190
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    • 2001
  • This study presents procedures and analysis methods for well known two field soil permeability tests, disc-tension infiltrometer and Guelph permeameter. Some case tests are demonstrated and then some problems involving the tests were clarified. This study may be helpful for practical field hydrogeologists.

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소음환경에 대한 근속년수별 작업자의 주관적 반응분석 (An Analysis of Subjective Responses on Noise Environment According to Operators' Continuous Service)

  • 이동춘;황규성;이임순
    • 산업경영시스템학회지
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    • 제12권20호
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    • pp.63-69
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    • 1989
  • This paper tries to define and analyse the subjective responses on noise environment according to operators continuous service in the field. The hypothesis of this paper is that the longer they serve in the same field, the more they feel seriously on noise effects. A predesigned enquete was handed out to 500 operators, and performed Friedman Test in order to check the hypothesis Concludingly, this paper accepts the hypothesis by year of continuous service-questionaire number analysis.

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전기철도의 전자기적합성에 관한 고찰 (Study for electromagnetic compatibility of electric train system)

  • 김민철;이장무;한문섭
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 춘계학술대회 논문집
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    • pp.883-888
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    • 2005
  • In modern system, electromagnetic environment are going worse with advancing electric and electronic technology, and this electromagnetic environment affect modern electric train system at the point of the safety problem. Therefore, each distributed system that is consisting electric train system have to prove there own electromagnetic compatibility through the field test. These distributed system can be considered as power supply system, signal & communication system and train system. In this study, essential field tests for electromagnetic compatibility of train system based on IEC national standard are suggested.

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