• Title/Summary/Keyword: Flow-delivery

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Pollutant Load Delivery Ratio for Flow Duration at the Chooryeong-cheon Watershed (추령천 유역의 유황별 유달율 계산)

  • Kim, Young-Joo;Yoon, Kwang-Sik;Son, Jae-Gwon;Choi, Jin-Kyu;Chang, Nam-Ik
    • Journal of The Korean Society of Agricultural Engineers
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    • v.52 no.4
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    • pp.19-26
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    • 2010
  • To provide the basic information for the water quality management of the Sumjin River Basin, delivery ratios for flow duration were studied. Using the day-interval data set of discharge and water quality observed from the Chooryeong-cheon watershed, the flow-duration and discharge-load relation curves for the watershed were established, then the load-duration curve was constructed. Delivery ratios for flow duration were also developed. Delivery ratios showed wide variation according to flow conditions. In general, delivery ratio of high flow condition showed higher value reflecting nonpoint source pollution contribution from the forest dominating watershed. To resolve this problem, a regression model explaining the relation between flow rate and delivery ratio was suggested. The delivery ratios for different flow regime could be used for pollutant load estimation and TMDL (Total maximum daily load) development.

Estimation of Pollutant Loads Delivery Ratio by Flow Duration Using Regression Equation in Hwangryong A Watershed (회귀식을 이용한 황룡A 유역에서의 유황별 유달율 산정)

  • Jung, Jae-Woon;Yoon, Kwang-Sik;Joo, Seuk-Hun;Choi, Woo-Young;Lee, Yong-Woon;Rhew, Doug-Hee;Lee, Su-Woong;Chang, Nam-Ik
    • Journal of The Korean Society of Agricultural Engineers
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    • v.51 no.6
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    • pp.25-31
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    • 2009
  • In this study, pollutant loads delivery ratio by flow duration in Hwangryoung A watershed was estimated. The delivery ratio was estimated with measured data by Ministry of Environment(MOE) and the regression equation based on geomorphic parameters. Eight day interval flow data measured by the MOE were converted to daily flow to calculate daily load and flow duration curve by correlating data of neighboring station which has daily flow data. Regression equation developed by previous study was tested to study watershed and found to be satisfactory. The delivery ratios estimated by two methods were compared. For the case of Biochemical oxygen demand(BOD), the delivery ratios of low flow condition were 7.6 and 15.5% by measured and regression equation, respectively. Also, the delivery ratios of Total phosphorus(T-P) for normal flow condition were 13.3 and 6.3% by measured and regression equation, respectively.

The Analytical Study on the Pressure Ripples in a Positive Displacement Vane Pump (유압 베인 펌프의 압력 맥동에 관한 연구)

  • 김기동;조명래;한동철;최상현
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1997.10a
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    • pp.225-231
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    • 1997
  • This paper reports on the theoretical study of the delivery pressure ripples of a positive displacement vane pump which is widely used for automobile power steering. Pressure ripples occur due to the flow tipples which induced cam ring profiles and reverse flow from the delivery ports. In this paper, the mathematical model for analyzing the pressure ripples has been presented, and set of the differential equationshave been solved using the Runge-Kutta method. As the results of analysis, instant ideal flow ripples, internal pressure, delivery pressure ripples, and delivery flow ripples have been presented. Internal pressure was related to delivery pressure variations, and amplitude of pressure tipples was increased with rotational speed and delivery pressure.

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Estimation of Pollutant Load Delivery Ratio for Flow Duration Using L-Q Equation from the Oenam-cheon watershed in Juam Lake (유량-부하량관계식을 이용한 주암호 외남천 유역의 유황별 유달율 산정)

  • Choi, Dong-Ho;Jung, Jae-Woon;Lee, Kyoung-Sook;Choi, Yu-Jin;Yoon, Kwang-Sik;Cho, So-Hyun;Park, Ha-Na;Lim, Byung-Jin;Chang, Nam-Ik
    • Journal of Environmental Science International
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    • v.21 no.1
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    • pp.31-39
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    • 2012
  • The objective of this study is to provide pollutant loads delivery ratio for flow duration in Oenam-cheon watershed, which is upstream watershed of Juam Lake. To calculate the delivery ratio by flow duration, rating curves and discharge-loads curves using measured data were established, then Flow Duration Curve(FDC) and pollutant loads delivery ratio curves were constructed. The results show that the delivery ratios for $BOD_5$ for abundant flow($Q_{95}$), ordinary flow($Q_{185}$), low flow($Q_{275}$), and drought flow($Q_{355}$) were 23.9, 12.7, 7.1, and 2.9%, respectively. The delivery ratios of same flow regime for T-N were 58.4, 31.2, 17.2 and 7.1%, respectively. While, the delivery ratios T-P were 17.3, 7.5, 3.4, and 1.1% respectively. In general, delivery ratio of high flow condition showed higher value due to the influence of nonpoint source pollution. Based on the study results, generalized equations were developed for delivery ratio and discharge per unit area, which could be used for ungaged watershed with similar pollution sources.

Estimating Nutrients Delivery Ratios at the Subwatershed Scale -A Case Study at the Bochung-A Watershed- (소유역 유달율 추정공식 개발 -보청A유역을 중심으로-)

  • Jeon, Ji-Hong;Choi, Dong-Hyuk;Lim, Kyung-Jae;Kim, Tae-Dong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.52 no.5
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    • pp.27-35
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    • 2010
  • The characteristics of delivered nutrient loads were analyzed and the regression equations to estimate delivery ratios of nutrients (TN and TP) were developed using HSPF simulation results at six subwatersheds within the Bochung A unit watershed during 1998-2007. TN delivery ratio was higher than TP delivery ratio because significant amounts of TP was considered to be attached at soil as ${PO_4}^-$ during delivery process from discharged point of nutrient source to main stream. As a results of correlation analysis, factors related to geomorphic characteristics had not statistical correlation with TN and TP delivery ratios. TN loading rate from living and specific stream flow had statistical negative and positive correlation, respectively, with TN delivery ratio. TP loading rates from all sources and from land cover and specific stream flow had statistical negative, negative and positive correlation, respectively. The specific stream flow represents the most strong correlation with nutrient delivery ratios. The regression equations to estimate delivery ratios for TN and TP were developed by including statistical correlated factors and showed high efficiency of 0.98 and 0.95 of coefficient of determination for TN and TP, respectively.

Stability analysis of drug delivery equipment in sports and exercise actions

  • Cuijuan Wang
    • Advances in nano research
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    • v.14 no.2
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    • pp.165-177
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    • 2023
  • Nanomotors are gaining popularity as novel drug delivery methods since they can move rapidly, penetrate deeply into tissues, and be regulated. The ability of manufactured nanomotors to swiftly transport therapeutic payloads to their intended location constitutes a revolutionary nanomedicine strategy. The nanomotors for the drug delivery purpose are released in the blood flow under the different physical conditions, so the stability investigation of these devices is essential before the production, especially in the sport and physical exercise conditions that the blood flow enhances. As a result, using dynamic analysis, this article investigates the stability of the nanomotor released in the blood flow when sport and physical activity circumstances increase blood flow. The considered nanodevice is made of a central motor, and nanotubes are used for the nanomotor blade, which is the drug capsule. Finally, the stability examination of nanomotor as the drug delivery equipment is discussed in detail, and the proposed results can present beneficial results in designing and producing small-scale intelligent devices.

A Study on the Measurement of Delivery Flow Ripple Generated by Hydraulic Axial Piston Pumps (유압용 액셜 피스톤 펌프의 유량맥동 계측에 관한 연구)

  • 이상기
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.8 no.2
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    • pp.35-43
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    • 1999
  • The paper describes an approach for measuring delivery flow ripple generated by oil hydraulic axial piston pumps. In order to reduce pressure ripple which cause to undesirable noise. vibration and fatigue in hydraulic systems it is indispensible measure a delivery flow ripple from pumps. Since the flow ripple measurement of flow pumps is independent of the dynamic characteristics of the connected hydraulic circuit the measurement of flow ripple is most suitable for pump fluid-borne noise rating. The measurement of flow ripple with high frequencies from axial piston pumps is made by applying the remote instantaneous flow rate measurement method which is based on the dynamic characteristics between pressure and flow rate in hydraulic pipeline. The measured flow ripple waveforms are influenced by the configuration of V-shaped triangular relief groove in the valve plate. It can be seen that the appropriate relief groove in valve plate reduces the pressure and flow ripple amplitude and frequency spectrum for high harmonics.

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Empirical Equation for Pollutant Loads Delivery Ratio in Nakdong River TMDL Unit Watersheds (낙동강 오염총량관리 단위유역 유달율 경험공식)

  • Kim, Mun Sung;Shin, Hyun Suk;Park, Ju Hyun;Kim, Sangdan
    • Journal of Korean Society on Water Environment
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    • v.25 no.4
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    • pp.580-588
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    • 2009
  • In this study daily flow rates and delivered pollutant loads of Nakdong river basin are simulated with modified TANK model and minimum variance unbiased estimator. Based on the simulation results, flow duration curves, load duration curves, and delivery ratio duration curves have been established. Then GIS analysis is performed to obtain several hydrological geomorphic characteristics such as watershed area, stream length, watershed slope and runoff curve number. Finally, multiple regression analysis is carried out to estimate empirical equations for pollutants delivery ratio. The results show that there is positive relation between the flow rates and delivery ratios, and the proposed empirical formulas for delivery ratio can predict well river pollutant loads.

Investigation on the Pollutant Delivery Characteristics using Physically Based Watershed Model (물리적 기반의 유역모형을 이용한 오염물질 유달 특성 규명)

  • Kim, Chul-Gyum;Kim, Nam-Won
    • Journal of Korean Society on Water Environment
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    • v.25 no.2
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    • pp.256-267
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    • 2009
  • A method of estimating pollutant delivery ratios considering watershed physical and meteorological characteristics and flow conditions using SWAT-K watershed model was described, and pollutant delivery characteristics during dry and rainy seasons, for monthly and seasonally, and with flow regimes were investigated for the Chungju dam watershed. Delivery ratios for sediment, T-N, and T-P showed higher values over 100% during dry and winter seasons with low pollutant loads and flows, and showed relatively uniform ones under 100% during rainy and summer seasons with concentrated loads and flows. It was found that mainly wet flows during summer seasons played very important roles in investigating the delivery characteristics of total or nonpoint pollutant loads, because more than 90% of total loads were influenced by nonpoint source, and discharged with the flows. From the results, we could find out the delivery characteristics with various watershed and flow conditions which are difficult to consider by actual measurement, and could get a foothold of estimating more reasonable and scientific allocated loads for water quality standard using the reliable method of estimating delivery ratios with a watershed model.

Geometry effect in the drug delivery for therapy with nanomedicines based on the conditions of the sport

  • Zhu, Lemei;Zou, Xuemin;Li, Xi;Zhang, Yuan;Liu, Juan;Xiang, Yuhan
    • Advances in nano research
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    • v.13 no.3
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    • pp.217-231
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    • 2022
  • This study investigates the geometrical impact on the nanomedicine drug delivery via nanodevices. A nanomotor made of the nanotube carrying the drug as the motor blade is considered in the blood flow. Physical activities change the blood flow, and sports training enhances the blood flow and plays a significant role in the stability of drug delivery devices. This paper studies the impact of geometrical parameters on the nanomotors carrying the nanomedicine. The effect of physical exercise on the dynamic response regarding the stability of drug delivery devices is discussed in detail.