• Title/Summary/Keyword: Sediment concentration

Search Result 847, Processing Time 0.033 seconds

An Efficient Method Of The Suspended Sediment-Discharge Measurement Using Entropy Concept

  • Choo, Tai-Ho
    • Water Engineering Research
    • /
    • v.1 no.2
    • /
    • pp.95-105
    • /
    • 2000
  • A method is presented which enables easily the computation of the suspended sediment discharge as the mean sediment concentration and mean flow velocity. This method has significant advantages over the traditional method, which principally depend on a set of measured concentration data. The method is based on both a new sediment concentration and mean sediment concentration equations which have been derived from the entropy concept used in statistical mechanics and information theory: (1) The sediment concentration distribution equations derived, are capable of describing the variation of the concentration in the vertical direction. (2) The mean concentration equation derived, is capable of calculating easily the mean concentration by using only one measured concentration in open channel. The present study mainly addresses the following two subjects : (1) new sediment concentration and mean sediment concentration equations are derived from the entropy concept : (2) An efficient and useful method of suspended sediment-discharge measurements is developed which can facilitate the estimation of suspended sediment-discharge in open channel. Flume and laboratory data are used to carry out the research task outlined above. An efficient method for determining the suspended sediment-discharge in the open channel has been developed. The method presented also is efficient and applicable in estimating the sediment transport in rivers and the sediment deposit in the reservoirs, and can drastically reduce the time and cost of sediment measurements.

  • PDF

Tank Model using Kalman Filter for Sediment Yield (유사량산정을 위한 Kalman filter를 이용한 탱크모델)

  • Lee, Yeong-Hwa
    • Journal of Environmental Science International
    • /
    • v.16 no.12
    • /
    • pp.1319-1324
    • /
    • 2007
  • A tank model in conjunction with Kalman filter is developed for prediction of sediment yield from an upland watershed in Northwestern Mississippi. The state vector of the system model represents the parameters of the tank model. The initial values of the state vector were estimated by trial and error. The sediment yield of each tank is computed by multiplying the total sediment yield by the sediment yield coefficient. The sediment concentration of the first tank is computed from its storage and the sediment concentration distribution(SCD); the sediment concentration of the next lower tank is obtained by its storage and the sediment infiltration of the upper tank; and so on. The sediment yield computed by the tank model using Kalman filter was in good agreement with the observed sediment yield and was more accurate than the sediment yield computed by the tank model.

폐금속광산 하류하천에서의 수변식물내 중금속의 축척에 관한 연구

  • 김주선;이재영;최상일
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 2004.09a
    • /
    • pp.235-240
    • /
    • 2004
  • This study is to study accumulation of the heavy metals by riparian vegetation throughout analysis of the heavy metal concentration in riparian vegetation, water, and sediment near mine drainage. According to analyzing concentration of the heavy metals in riparian vegetation, water, and sediment, the heavy metal was indicated at the leaf significantly. Compared with the concentration of sediment soil, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 2.6, 2.6, 2.5, non-detect, and 1.5 times in leaf, Also those concentration have 9.6, 16.6, 2.5, 1.6, and 2.5 times in root. As the results, the author can know the sediment has a very relative to vegetation in mine drainage, because the increasing of concentration of heavy metal in sediment gives the more accumulative concentration of heavy metal in vegetation. Compared with the concentration of contaminated site and non-contaminated site. As, Cd, CN, Pb, Zn the maximum concentration in sediment soil was higher 5.7, 258.1, 10.9, 370.0, and 298.3 times respectively. In case of vegetation, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 5.6, 62.3, 5.0, non-detect, and 30.6 times in leaf. Also those concentration have 8.5, 63.3, 2.6, 60.7, and 62.1 times in root. In this study, the author can surmise that there indicated a lot of adsorption with the heavy metal concentration in contaminated mine drainage.

  • PDF

Comparison of Sediment Yield by IUSG and Tank Model in River Basin (하천유역의 유사량의 비교연구)

  • Lee, Yeong-Hwa
    • Journal of Environmental Science International
    • /
    • v.18 no.1
    • /
    • pp.1-7
    • /
    • 2009
  • In this study a sediment yield is compared by IUSG, IUSG with Kalman filter, tank model and tank model with Kalman filter separately. The IUSG is the distribution of sediment from an instantaneous burst of rainfall producing one unit of runoff. The IUSG, defined as a product of the sediment concentration distribution (SCD) and the instantaneous unit hydrograph (IUH), is known to depend on the characteristics of the effective rainfall. In the IUSG with Kalman filter, the state vector of the watershed sediment yield system is constituted by the IUSG. The initial values of the state vector are assumed as the average of the IUSG values and the initial sediment yield estimated from the average IUSG. A tank model consisting of three tanks was developed for prediction of sediment yield. The sediment yield of each tank was computed by multiplying the total sediment yield by the sediment yield coefficients; the yield was obtained by the product of the runoff of each tank and the sediment concentration in the tank. A tank model with Kalman filter is developed for prediction of sediment yield. The state vector of the system model represents the parameters of the tank model. The initial values of the state vector were estimated by trial and error.

Research on the Sediment Characteristics in Change Structural Shape of Agricultural Irrigation (농업용수로 구조적 형상 변화에 따른 퇴적 특성 연구)

  • Park, Jung Koo;Kim, Myeong Hwan;Song, Chang Seob
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.57 no.6
    • /
    • pp.69-77
    • /
    • 2015
  • The objective of this study was to evaluate the performance of selected sediment reduction methods to reduce sediment discharges from drain and irrigation of different types (concrete canals, soil canals). This study was carried out to analysis for the suspended sediment concentration and sediment of drain and irrigation by velocity of flow. The results of study were analysised and summerized as follow. Sedimentation characteristics and size of soil sediment from the concrete and soil canals of downstream smaller than upstream. Suspended sediment concentration and flow times from the suggestion canals bigger than open canal. Structural shape of the canal decreases the velocity of flow also affects the suspended sediment concentration and flow times.

A Study on Controlling Efflux Sediment Diffusion by Jetty Construction at Small Estuary (소규모 하구에서 토사유출 확산제어에 관한 연구)

  • Park, Sang Kil;Park, Hyun Su;Yoon, Jong Su;Lee, Si Ho
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.29 no.5B
    • /
    • pp.483-491
    • /
    • 2009
  • In this study, a jetty construction is taken into account for the reduction of sediment diffusive concentration incoming from the upstream river due to the urbanization and industrial development and to minimize the effects on the coastal ecosystems. The field observation and numerical calculation are conducted to analyze the diffusion zone of sediment concentration in the small estuary and coastal area. The specification of the installed jetty which is able to control the sediment concentration was decided based on the prediction of the dispersion area changes in space and time. The selected size and layout for the jetty design were examined for the dispersion zone by numerical calculation and field observation. As a result, the jetties constructed in the estuary retarded the dispersion rate of sediment concentration, so that the effect area of sediment dispersion was obviously decreased. In addition, the measured field data indicated that the sediment deposition in the inside of dikes could be controlled and the right side area of jetties could be preserved without influx sediment diffusion.

A Direct Inversion Method to Remotely Measure the Concentration Profile of Suspended Sediment Using Acoustic Backscatterance

  • Lee, Tae-Hwan
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
    • /
    • 1995.10a
    • /
    • pp.48-50
    • /
    • 1995
  • The use of acoustics to measure the concentration profile of suspended sediment become increasing common. Field studies have shown the usefulness of remotely measuring the suspended sediment concentration with high spatial and temporal resolution. Techniques that allow for the conversion of the backscattered acoustic intensity into suspended sediment concentration have been developed concurrent with instrumentation. (omitted)

  • PDF

Influence of Heavy Metal on Riparian Vegetation in Downstream Areas of Disused Metal Mines (폐금속광산지역의 하천퇴적물에서 중금속이 식물에 미치는 영향에 관한 연구)

  • Ahn, Tae Woong;Lee, Joung An;Oh, Jong Min
    • Journal of Environmental Impact Assessment
    • /
    • v.18 no.4
    • /
    • pp.209-218
    • /
    • 2009
  • The purpose of this study was to accumulation of the heavy metals by riparian vegetation throughout analysis of the heavy metal concentration in riparian vegetation, water, and sediment near mine drainage. According to analyzing concentration of the heavy metals in riparian vegetation, water, and sediment the heavy metal was indicated at the leaf significantly. Compared with the concentration of sediment soil, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 2.6, 2.6, 25, non-detect, and 15 times in leaf. Also those concentration have 9.6, 16.6, 25, 1.6, and 25 times in root. As the results, the author can know the sediment has a very relative to vegetation in mine drainage. because, the increasing of concentration of heavy metal in sediment gives the more accumulative concentration of heavy metal in vegetation. Compared with the concentration of conta minated site and non-contaminated site. As, Cd, CN, Pb, Zn the maximum concentration in sediment soil was higher 5.7, 258.1, 10.9, 370.0, and 298.3 times respectively. In case of vegetation, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 5.6, 62.3, 5.0, non-detect, and 30.6 times in leaf. Also those concentration have 8.5, 63.3, 2.6, 60.7, and 62.1 times in root. In this study, the author can surmise that there indicated a lot of adsorption with the heavy metal concentration in contaminated mine drainage.

Enhanced vertical diffusion coefficient at upper layer of suspended sediment concentration profile

  • Kim, Hyoseob;Jang, Changhwan;Lhm, Namjae
    • Ocean Systems Engineering
    • /
    • v.2 no.4
    • /
    • pp.289-295
    • /
    • 2012
  • Assume fluid eddy viscosity in the vertical direction is parabolic. Sediment particles diffuse with the given fluid eddy viscosity. However, when the vertical diffusion coefficient profile is computed from the suspended sediment concentration profile, the coefficient shows lager values than the fluid mixing coefficient values. This trend was explained by using two sizes of sediment particles. When fine sediment particles like wash load are added in water column the sediment mixing coefficient looks much larger than the fluid mixing coefficient.

Distributions and Sources of Polycyclic Aromatic Hydrocarbons in the Tidal Flat Sediments from Incheon Coastal Area (인천연안 갯벌의 다환방향족탄화수소의 농도분포와 발생원 평가)

  • Park, Jung Hwan;Lee, Choong Dae;Kim, Jin Han
    • Journal of Wetlands Research
    • /
    • v.15 no.4
    • /
    • pp.441-451
    • /
    • 2013
  • Samples for estimating concentrations of polycyclic aromatic hydrocargons(PAHs), total petroleum hydrocarbons(TPHs), and benzene-toluene-ethylbenzene-xylene(BTEX) were collected at the tidal flat sediments of 8 coastal sites in Incheon, at seventy-two sampling stations for the surface sediment and twenty-four stations for the sediment core, twice in the spring and fall in 2011. This study was performed to evaluate the distributions of seasonal and spatial concentrations of PAHs, TPHs, and BTEX in the tidal flat sediments. The source origin of PAHs were carried out. The total average concentration of PAHs in the tidal flat sediment was $95.62{\mu}g/kg$. The characteristic of PAHs concentration distributions was observed that the average concentration in the autumn was lower than that in the spring, and higher concentration in the sediment core than the surface sediment, and greater vertical concentration at the top rather than the bottom in the sediment core. The total average concentration of TPHs at all sampling sites was in the value of 46 mg/kg. The characteristic of the TPHs concentration distribution was observed that the average concentration in the fall was much higher than that in the spring, and higher concentration in the surface sediment than the sediment core. The possible source of PAHs inputs were mainly derived from both pyrogenic and petrogenic origin at the surface sediment at Janghwari site and the sediment cores of both Sorae and Okyeon sites, while the rest sites of study areas originated with pyrogenic combustion.