• Title/Summary/Keyword: Discharge estimation

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Insulation Performance Estimation of Main Relays by Partial Discharges (부분방전에 의한 주계전기의 절연성능 평가)

  • Kil, Gyung-Suk;Kim, Il-Kwon;Park, Dae-Won;Song, Jae-Yong;Lee, Gang-Won;Cho, Eun-Je
    • Journal of the Korean Society for Railway
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    • v.10 no.4
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    • pp.388-392
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    • 2007
  • A new dielectric test on main relays of electric traction vehicles, the partial discharge(PD) test, is proposed. The PD test will not affect the insulation performance of specimen during the test and provide much more detailed information on insulation, the types of defects, and so on. Insulation performance of relays is estimated by discharge inception voltage(DIV), discharge extinction voltage (DEV), and apparent charge as a function of test voltage and time. Three main relays of different manufacturing date were estimated by applying AC voltage with three patterns in ranges of $0{\sim}1,200[V]$. From the results, we could estimate insulation state and which types of defects exist in them.

Evaluation of Applicability for Nonpoint Discharge Coefficient using Watershed Model (유역모형을 이용한 비점배출계수 적용성 평가)

  • Lee, Eun Jeong;Kim, Tae Geun
    • Journal of Environmental Impact Assessment
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    • v.21 no.3
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    • pp.339-352
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    • 2012
  • Total maximum daily load have been implemented and indicated that nonpoint discharge coeffients in flow duration curve were 0.50 of Normal flow duration ($Q_{185}$) and 0.15 of low flow duration($Q_{275}$). By using SWAT, nonpoint discharge coefficients are studied with the conditions of the instream flow and the rainfall in two study areas. The nonpoint discharge coefficient average of BOD and TP for normal flows duration in 3 years are 0.32~0.36 and 0.28~0.31. For the low flow duration, the nonpoint discharge coefficient avergae of BOD and TP were 0.10~0.12 and 0.10~0.11. These are lower than the coefficients of total maximum load regulation. There are big differences between one of regulation and one of SWAT for the normal flow duration. With the consideration of rainfall condition, the nonpoint discharge coefficient of flood flow duration are influenced on the amount of rainfalls. However, the nonpoint discharge coefficients of normal flow duration and low flow duration are not effected by the rainfall condition. Since the spatial distribution and geomorphological characteristics could be considered with SWAT, the estimation of nonpoint discharge coefficient in watershed model is better method than the use of the recommended number in the regulation.

Change of Water Discharge Capability of Sluice Caisson for Tidal Power Plant According to Installation of Rubble Mound (사석마운드 설치에 따른 조력발전용 수문의 통수성능 변화)

  • Lee, Dal-Soo;Oh, Sang-Ho;Yi, Jin-Hak;Park, Woo-Sun;Cho, Hyu-Sang;Kim, Duk-Gu
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.266-269
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    • 2008
  • In this study, the results of experimental investigation on the water discharge capability of sluice caisson for tidal power plant were presented. In particular, the focus of the study was placed on the examination of change in water discharge capability of a sluice caisson according to the installation of rubble mound. For this purpose, a hydraulic experiment was carried out in an open channel flume with a great care to the measurement of discharge and water level in the flume since they greatly affects the estimation of the discharge capability of each sluice caisson. In the analysis, the experimental data of four different sluice models were used, which showed that the installation of rubble mound affects in different manner depending on each sluice caisson model. When each of the four sluice models were placed on the rubble mound respectively, the water discharge increased for one sluice caisson, whereas decreased for other three sluice caissons. Further detailed analysis is needed to quantitatively estimate the influence of installation of rubble mound on the water discharge capability of a sluice caisson.

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Estimation of Partial Discharge Sources in a Model GIS through the Analysis of UHF Signals (UHF 신호 분석을 통한 모의 GIS내 부분방전원 추정)

  • 전재근;곽희로;노영수;이동준
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.4
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    • pp.112-117
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    • 2004
  • This paper describes the analysis of the UHF signal characteristics due to the partial discharge sources which can exist in a GIS. For the experiment, a model GIS was made and 5 types of discharge source were created as follows; corona discharge, surface discharge, void discharge, discharge due to free particle, discharge from floating electrode. The frequency spectra and the phase characteristics of UHF signals were induced by UHF signal analysis. The results were quantified to systematically adapt to analyze the PD sources in the GIS and utilized as algorithm data based on the neural network for Back-Propagation Algorithm with a multi-layer structure. The perception rate of the constructed algorithm showed approximately 94[%] and 82[%] in learning and testing data, respectively.

Estimation of the Probability Flood Discharge for Small and Middle Watersheds (중소하천 유역에서의 확률홍수량 분석)

  • Yun, seong-jun;Yu, ui-geun;Kim, byeong-chan;Lee, jong-seok
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.442-448
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    • 2009
  • Recently, the natural disaster has occurred as a heavy snow fall, drought and flood by abnormal weather. The damage of human and property by flood is most serious problem among those natural disaster. In order to prepare structural or non-structural measure, to estimate exact flood discharge is important element. This study analyze frequency of hour-unit rainfall data and estimate probability flood discharge by HEC-HMS as changing method of runoff analysis. Also, this study analyze the peak flood discharge sensibility according to Curve Number(CN) with the return period. As a result of estimation of probability flood discharge with the variety CN, to select Antecedent Moisture To select suitable condition(AMC) is important parameter because flood discharge is estimated 40% gap according to AMC.

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