• Title/Summary/Keyword: Discharge estimation

Search Result 559, Processing Time 0.036 seconds

A Study on Discharge Estimation by Representative Parameter Method in Open Channels (개수로에서의 대표 매개변수 방법에 의한 유량산정에 관한 연구)

  • Choo, Tai Ho;Chae, Soo Kwon
    • Journal of Wetlands Research
    • /
    • v.14 no.4
    • /
    • pp.637-644
    • /
    • 2012
  • The discharge estimation that means the most important element in a wetlands ecosystem and rivers is a prime concern. All the interim, this discharge estimation depends on stage-discharge curve, but the limitation of stage-discharge curve that uses only connection between the stage and discharge is widely well known. Thus, this paper proposed a method of discharge estimation in a section through "representative parameter estimation method" by using Manning and Chezy equations that have been extensively used in an open channel. Each result is presented by both RMSE and Discrepancy Ratio. The scale difference for the results between laboratory and natural open channel data existed, but the each result showed that the estimated discharge agree with the measured discharge. If the verification and improvement are conducted in various rivers through continuous study, the easy and rapid discharge estimation will be possible. So, the proposed method will be utilized in the water resources fields.

A Basic Study on the Estimation of Discharge Current Waveform and the Insulation Diagnosis by the Measurement of Electromagnetic Environment (전자환경 측정에 의한 방전전류 파형추정과 절연진단의 기초 연구)

  • Park, Gwang-Seo;Kim, Gi-Chae;Kim, Lee-Guk;Park, Won-Ju;Lee, Gwang-Sik
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.51 no.10
    • /
    • pp.492-499
    • /
    • 2002
  • This paper presents the method for an estimation of discharge current waveform in short gap discharge by radiated electromagnetic fields. The method of current waveform estimation is to use the one antenna method (single field method) with a measured electric or magnetic field at given field point by a time domain antenna. In order to verify the availability of the estimation theory, the discharge current waveform estimation was performed by one antenna methods using the measured electric fields of Wilson & Ma and compared with experiments. In addition diagnosis technique for power equipments is able to prevent from large accidents by finding signs of tile accidents before they happen. From the results of the estimation of discharge current, we have a possibility for the application of insulation diagnosis technique for power equipments using S$F_6$ gas. From this point of view, this paper simulated discharge progress and partial discharge by using needle-plan electrodes system in S$F_6$, studied the distribution of frequency spectrum of the radiated electromagnetic waves using a biconical antenna and a spectrum analyzer. From the experimental results of this study, according to the consideration of the mutual relation between frequency spectrum of the radiated electromagnetic waves and discharge progress, it was confirmed that detecting Partial discharge and estimating discharge progress in S$F_6$ could be Possible.

Estimation of Discharge Load due to Combined Sewer Overflows in the Management of Total Maximum Daily Loads (수질오염총량관리 관거월류부하 변화에 따른 배출부하량 산정방법)

  • Park, Jun Dae;Oh, Seung Young;Choi, Ok Youn
    • Journal of Korean Society on Water Environment
    • /
    • v.27 no.3
    • /
    • pp.293-299
    • /
    • 2011
  • The quantity of a discharge load can change with changes in rainfall in the area with a combined sewer system (CSS). To evaluate the implementation appropriately in the management of total maximum daily loads (TMDLs), the effects of rainfall changes should be considered in the estimation of the discharge load. The rainfall condition for the estimation of the discharge load in a certain year should be standardized to the same rainfall condition as that of the reference year. However, the calculation process is very complicated with its potential limitations. This study investigated and developed relatively simple methods for estimating the discharge load. Load conversion method (LCM) is designed to convert the discharge load under the current rainfall condition into that of the reference rainfall conditions. Simple rainfall data method (SRDM) is to simplify the estimation process of the discharge load by the simple conversion of rainfall data. These methods were applied to calculate the discharge load and examine the estimation results. From the results of this study the application of these methods may be useful for estimating the discharge load in the TMDL process.

A Study on Estimation by Depth Integrating Method of Sediment Discharge (수심적분법에 의한 유사량 추정연구)

  • 서승덕;김활곤;우효섭
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.38 no.1
    • /
    • pp.90-97
    • /
    • 1996
  • In Korea, total sediment discharge of a river has been estimated simply by using certain sediment transport formulas including, among others, Einstein's formula. Those formular, however, are known not to be reliable enough for the result calculated by them to be used directly to river planning and management. Therefore, the study used the Modified Einstein Procedure to the estimation of total sediment discharge, because this method is reliable estimated by measurement. Here, measurement of sediment discharge used depth integrating method. The major results obtained from the study for estimation by depth integrating method of sediment discharge in Naeseong stream are as follow; 1 The sedeiment characteristics of Naeseong stream are; The distribution of sediment grain size shows that silt and clay are 55% and sand is 45%. and the bed load sediment grain size is constituted that sand contained with the grain size from O.062mm to 2.0mm is 80% 2. The sediment rating formulas derived from the regression analysis between the sediment discharge and flow discharge are; Seogpo-Gyo : Qs=$0.017 \times 10^{-4} Q^{2.352}$, where discharge is l0cms $0.074 \times 10^{-4} Q^{2.066}$, where discharge is l0cms

  • PDF

Estimation of Discharge Current Waveshapes in Short Gap Discharge by One Antennal Method (1 안테나 법에 의한 미소 간극의 방전 전류파형 추정)

  • 김기채;이광식;이동인
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.9 no.4
    • /
    • pp.499-505
    • /
    • 1998
  • This paper presents the method for an estimation of discharge current waveshapes in short gap discharge by a radiated electromagnetic field. The method of currentwaveform estimation described is using the one antenna method(single field method) with a measured electric or magnetic fields at given field point by a time domain antenna. In order to verify the availability of the estimated theory, the discharge current waveshape estimation was performed by one antenna method using the measured electric fields of Wilson & Ma and compared with experiments.

  • PDF

Estimation of Discharge Current Waveshapes in Short Gap Discharge by Radiated Electromagnetic Fields (방사 전자파에 의한 미소 간극 방전원의 방전 전류파형 추정)

  • 김기채;이광식;이동인
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.11 no.2
    • /
    • pp.259-267
    • /
    • 2000
  • This paper presents the method for an estimation of discharge current waveshapes in short gap discharge by radiated electromagnetic fields. The method of current waveform estimation described is using the one antenna method(single field method) and two antennal method(complex field method) with a measured electric or magnetic fields at given field point by a time domain antenna. In order to verify the availability of the estimation theory, the discharge current waveshape estimation was performed by one and two antenna methods using the measured electric fields of Wilson & Ma and compared with experiments.

  • PDF

Unit Mass Estimation and Analysis from Textile Spinning/Weaving Manufacturing Facility Nearby Nakdong River Basin (낙동강 수계에서 제사방적제조 업체에 대한 공정별 원단위산정 및 분석)

  • Lee, Hongshin;Son, Gontae;Gu, Jungeun;Konboonraksa T.;Lee, Hongtae;Lee, Seunghwan
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.22 no.5
    • /
    • pp.541-550
    • /
    • 2008
  • In this investigative study, the unit mass discharge for the major water quality parameters such as flowrate, SS, BOD, CODmn, CODcr, TN, TP from textile spinning/weaving industry nearby Nakdong river basin was estimated. To represent the respective industries, three companies from hundreds of textile spinning/weaving industries located in Nakdong river basin was carefully selected based on its manufacturing goods, flowrate and location for the estimation of unit mass discharge based on unit operation and process. There was a drastic decrease of unit mass discharge estimation between influents and effluents of water quality parameters, which represents the removal capacity of wastewater treatment plant. With the advent of new regulation on the imposed payment proportional to the total amount of pollutants discharge into the water body, the concept of cleaner production technology should be employed in the unit operation/process in wastewater treatment plant as well as textile manufacturing procedure to minimize the levy on the pollutants discharge. Unit mass discharge estimations of unit process (estimated in this study) in major water quality parameters (SS, BOD, COD, TN and TP) based on land were similar to those of composite process (estimated by National Institute of Environmental Research). But the unit mass discharge estimations of unit process in BOD and CODmn based on total sale were much higher than those of composite one while in SS, TN and TP similar to each other. For the detailed estimation of the imposed payment, unit mass estimation based on unit process should be further emphasized.

Estimation of River discharge using Very High-Resolution Satellite Data in Yangtze River

  • Zhang, Jiqun;Xu, Kaiqin;Watanabe, Masataka;Sun, Chunpeng
    • Proceedings of the KSRS Conference
    • /
    • 2002.10a
    • /
    • pp.728-733
    • /
    • 2002
  • The measurement of river discharge is among the most fundamental observations and is necessary for understanding many water-related issues, such as flooding hazards, sediment transportation, and nutrient movement. Traditionally river discharge is estimated by measuring the water stage and converting the measurement to discharge using a stage-discharge rating curve. The possibility of monitoring river discharge from satellites has been largely ignored, because it is difficult to measure water surface information from space with sufficient precision. In this paper, an efficient approach to discharge estimation using mainly satellite data is developed and described. The proposed method, which focuses on the measurement of water-surface width coupled with river width-stage and stage-discharge relationships, is applied to the Yangtze River with good results.

  • PDF

Discharge Estimation Using Non-dimensional Velocity Distribution and Index-Velocity Method in Natural Rivers (자연하천에서 무차원 유속분포-지표유속법을 이용한 유량산정)

  • Kim, Chang-Wan;Lee, Min-Ho;Jung, Sung-Won;Yoo, Dong-Hoon
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2007.05a
    • /
    • pp.855-859
    • /
    • 2007
  • It is essential to obtain accurate and highly reliable streamflow data for water resources planning, evaluation and management as well as design of hydraulic structures. A new discharge estimation method, which is named 'non-dimensional velocity distribution and index-velocity method,' was proposed in this research. This method showed very close channel discharges which were calculated with the exiting velocity-area method. When velocity-area method is used to estimate channel discharge, it is required to observe point velocities at every desired point and vertical using a current meter like Price-AA. However 'non-dimensional velocity distribution and index-velocity method' is used, it become optional to observe point velocities at every desired point and vertical. But this method can not be applied for the cases of very complex and strongly asymmetric channel cross-sections because non-dimensional velocity distribution by entropy concept may be quite biased from that of natural rivers.

  • PDF

Rainfall Correction of Radar Image Data and Estimation Runoff of Urban Stream using Vflo (레이더 자료의 강우보정 및 Vflo를 활용한 도심하천의 홍수량 산정)

  • Kang, Bo-Seong;Yang, Sung-Kee;Kim, Yong-Seok
    • Journal of Environmental Science International
    • /
    • v.26 no.4
    • /
    • pp.411-420
    • /
    • 2017
  • This research aims at comparing the accuracy of flood discharge estimation. For this, we focused on the Oedo watershed of Jeju Island and compared flood discharge by analyzing the values as follows: (1) the concentration of the lumped model (HEC-HMS) and distributed model (Vflo), and (2) the in-situ data using Fixed Surface Image Velocimetry (FSIV). The flood discharge estimation from the HEC-HMS model is slightly larger than the Vflo model results. This result shows that the estimations of the HEC-HMS are larger than the flood discharge data by 4.43 to 36.24% and that of the Vflo are larger by 8.49 to 11%. In terms of the error analysis at the peak discharge occurrence time of each mapping, HEC-HMS is one hour later than the measured data, but Vflo is almost the same as the measured data.