• Title/Summary/Keyword: Small reservoir

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Survey on the actual injured condition and wintery ecology of Black vulture(Aegypius monachus) (독수리(Aegypius monachus)의 월동생태 및 부상실태 조사)

  • Kim, Jong-Taek;Park, Cheol-Min;Kim, Young-Jun;Pak, In-Chul
    • Korean Journal of Veterinary Service
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    • v.30 no.3
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    • pp.467-472
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    • 2007
  • Eurasian black vulture (Aegypius monachus) belongs to family Accipitridae and is a raptor preying small birds and mammals. It is a wintering bird residing from the mid of November to the late of March in Korea. Although Eurasian black vulture population wintering at Korea is gradually increased, the efficient rescue and treatment for injured Eurasian black vultures are still problematic, due to lack of basic data. Therefore, in this survey, to obtain basic resources for establishing more efficient rescue system, we surveyed the number of Eurasian black vultures wintering at Gangwon province, wintering ecology and injury state of Eurasian black vulture. Survey area was Togyo reservoir at Cheorwon, Seonan basin at Yangoo and Wolsong reservoir at Chuncheon from November 2004 to March 2005. From 12 rescued Eurasian black vultures, physical examination, total plasma protein (TPP) and packed cell volume (PCV) were measured. To survey injury state of Eurasian black vultures wintering at Gangwon province, we surveyed the cause, morbidity and mortality from 103 Eurasian black vultures, based on medical records from animal rescue teams. The number of eurasian black vultures were gradually increased from November, peaked at Feburary, then steeply decreased at March. Eurasian black vultures showed the most vigorous activity around 1 PM within a day. In physical examination, mean body weight was $9.6{\pm}1.22kg$, body length was $1130{\pm}45.4mm$. No statistically significant difference in body weight and length between male and female eurasian black vultures was observed. Mean PCV was $40.2{\pm}2.7%$, while mean TPP was $5.86{\pm}0.8mg/dl$. The most common cause of injury and mortality was intoxication, while that of morbidity was fatigue.

A Study of Changes in the Water Quality of Agricultural Reservoirs due to Drought (가뭄으로 인한 농업용 저수지의 수질 변화 연구)

  • Cho, SungHyen;Hwang, Soonho;Lee, Dongguen;Lee, Guntaek;Choi, Jung-Hoon
    • Journal of the Korean earth science society
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    • v.43 no.1
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    • pp.110-118
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    • 2022
  • Frequent drought damage has resulted in the polarization of water resources. In Korea, local periodic abnormal droughts continued to occur between 2011 and 2017, resulting in decreased water storage rates of small-scale reservoirs designed with a frequency of 10-year droughts. This decrease can degrade water quality and limit the use of already secured quantities. Therefore, to prepare for and overcome drought, quality management and recalculation of drought frequency are required. This study estimates the potential pollutants causing quality changes in the reservoir. In addition, it reviews the decrease in storage and consequent changes in the quality of a reservoir during drought.

Analysis of Parallel Reservoir Water Supply Capacity According to Water Supply Changes (용수공급 변화에 따른 병렬저수지 용수공급 능력 해석)

  • Jea Min Park;Ki bum Park
    • Journal of Environmental Science International
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    • v.32 no.10
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    • pp.675-684
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    • 2023
  • In this study, the water supply reliability of the andong and Imha dam was analyzed using inflow data for 360 months from 1993 to 2022 through allocation model. First, in the analysis results of additional water supply to Deagu city, the water supply reliability of Rule (B) was the highest at 86% for andong dam, 84% for imha dam, and 80% for the control point. However, when the planned supply was supplied, the analysis results showed 94%, 93%, and 90%. Next, in the quantitative reliability analysis results, when considering additional water supply to Deagu city, Rule (A), Rule (B), and Rule (C) were analyzed as 88%, 88%, and 88%, respectively, based on the control point. When supplying the planned water supply, the quantitative reliability analysis results were 95% equally based on Rule (A), Rule (B), and Rule (C). Because of evaluating the two reliability methods, the number of shortages increases significantly when additional water is supplied to Daegu City, but the shortage is generally 5-7%, resulting in a relatively small shortage compared with the increase in the number of shortages. In the case of resilience and vulnerability, additional water supply to Daegu City takes more than two months to restore than the existing planned water supply, and the average shortage was calculated to be smaller than that of supplying the planned water. According to the results of the analysis, Andong dam has an average water storage of 130x106 m2 and Imha dam has 50x106 m2. In this deficient water supply can be compensated by water from the Nakdong river.

Development of an Event Rainfall-Runoff Model in Small Watersheds

  • Lee, Sang-Ho;Lee, Kil-Seong
    • Korean Journal of Hydrosciences
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    • v.6
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    • pp.81-98
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    • 1995
  • A linear reservoir rainfall-runoff system was developed as a rainfall-runoff event simulation model. It was achieved from large modification of runoff function method. There are six parameters in the model. Hydrologic losses consist of some quantity of initial loss and some ratio of rainfall intensity followed by initial loss. The model has analytical routing equations. Hooke and Jaeves algorithm was used for model calibration. Parameters were estimated for flood events from '84 to '89 at Seomyeon and Munmak stream gauges, and the trends of major parameters were analyzed. Using the trends, verifications were performed for the flood event in September 1990. Because antecedent rainfalls affect initial loss, future researches are required on such effects. The estimation method of major parameters should also be studied for real-time forecasting.

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Viscosity Measurement of Non-Newtonian Fluids Using the Transient Flow Phenomena in the Capillary Tube (모세관내 과도유동현상을 이용한 비뉴턴유체의 점도측정)

  • Cho, Min-Tae;Suh, Sang-Ho;Yoo, Sang-Sin
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.738-741
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    • 2001
  • The purpose of the present study is to measure the viscosity of liquid in the capillary tube viscometer using the unsteady flow concept. The capillary tube viscometer is consisted of a small cylindrical reservoir, capillary tubes, and the mass flow rate measuring system interfaced with computer. Two capillary tubes with 1.152 and 3.002 mm I.D. are used to determine the diameter effects on the viscosity measurements. The instantaneous shear rate and gravitational driving force in the capillary tube are determined by measuring the mass flow rate through the capillary tube instantaneously. The measured viscosities of water and aqueous Separan solution are in good agreement with the reported experimental data.

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Transient Evolution of Overlapped EDL Fields in a Microfluidic Channel (미소유동 채널에서 중첩된 전기이중층 구조의 과도 형성과정)

  • Kwak, Ho-Sang;Hasselbrink, Jr., Ernest F.
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1528-1533
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    • 2004
  • A numerical investigation is made of transient evolutionary prcocess of electroosmotic flow in a two-dimensional microchannel connected to a reservoir. The channel height is very small so that two electric double layers forming on the charged surfaces are overlapped. Transient transports of ions in the electrolyte solution are computed by integrating the Nernst-Planck equation together with the Poisson equation for electric potential. The numerical results illustrate that there are two distinct transient phases. The physical mechanisms and relevant time scales for the transient evolution are described.

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Rainfall Runoff Simulation Using Grid-Based Distributed Model for a Small Agricultural Reservoir Watershed (격자기반 분포형모형을 활용한 농업용 저수지유역의 홍수유출모의)

  • Jung, In-Kyun;Park, Jong-Yoon;Kim, Seong-Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.953-956
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    • 2009
  • 본 연구는 농업용저수지유역을 대상으로 분포형 강우-유출모형을 적용해 봄으로서 차후 본 연구대상유역의 분포형 강우유출모형을 이용한 설계홍수량 산정에 활용해 보기 위한 사전연구이다. 농업용저수지유역을 대상으로 모의하기 위하여 자동수위계를 통하여 저수지 수위자료가 주기적으로 기록되고 있는 계룡저수지 유역($15.4km^2$)을 선정하였으며, 주요 공간매개변수는 30m 격자해상도로 구축하였다. 관측유량자료는 수위-내용적-방류량 관계곡선에 의하여 수위변화에 따른 내용적 변화량을 유입량으로 가정하여 환산토록 하였으며, 곡선의 진동이 다소 작고 상태가 양호한 3개 강우사상을 대상으로 분석하였다. 대상유역의 2개 강우관측소(복룡, 반포)의 강우량을 IDW 방법에 의해 공간분포시켜 적용하였으며, 모형의 분석결과, 결정계수($R^2$)는 평균0.88, 용적보존지수(VCI)는 평균 0.14, 첨두유량의 상대오차 ($EQ_p$)는 평균 $0.11m^3/s$로 분석되었다.

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PWM Switch Modelling of Boost Converter for Photovoltaic System (PWM 스윗치를 이용한 햇빛발전 시스템용 부스트 컨버터 모델링)

  • Kim, H.J.;Choi, J.Y.;Yu, G.J.;Jung, Y.S.;Choi, I.;Ahan, H.S.
    • Proceedings of the KIEE Conference
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    • 2003.04a
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    • pp.341-348
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    • 2003
  • Photovoltaic systems normally use a maximum power point tracking (MPPT) technique ta continuously deliver the highest possible power to the load when variations in the insolation and temperature occur. A simple method of tracking the maximum power points (MPPs) and forcing the boost converter system to operate close to these points is presented through deriving small-signal model and transfer function of boost converter. This paper aims at modeling boost converter including equivalent series resistance of input reservoir capacitor by state-space-averaging method and PWM switch model with properly designed controller for maximum photovoltaic power tracking control.

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Proposal for Management of Small Reservoirs (기술사 마당 - 소규모 저수지 관리를 위한 제언)

  • Koo, Bon-Chung
    • Journal of the Korean Professional Engineers Association
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    • v.45 no.4
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    • pp.62-66
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    • 2012
  • An effective management of reservoir, an agricultural infrastructure, requires an establishment of a good management system by means of unification of managing entity; training of manpower and their deployment for scientific management by expert group; carrying out repair / strengthening works based on periodic in-depth inspection results. In particular, continuous budget allocation as well as cultivating good management mind of managing entity are essential for undertaking periodic precise and / or in-depth inspections for assessing the functionality / safety of facilities and proper repair / strengthening works for satisfying the up-to-date facilty standarda and changing environmental conditions.

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Boost Converter Modeling of Photovoltaic System Using PWM Switch Model (PWM 스윗치 모델을 이용한 PV용 Boost Converter Modelling)

  • Kim, H.J.;Lee, K.O.;Choi, J.Y.;Jung, Y.S.;Yu, G.J.;Kwon, J.D.
    • Proceedings of the KIEE Conference
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    • 2002.11d
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    • pp.286-293
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    • 2002
  • Photovoltaic systems normally use a maximum power point tracking (MPPT) technique to continuously deliver the highest possible power to the load when variations in the insolation and temperature occur. A simple method of tracking the maximum power points (MPPs) and forcing the boost converter system to operate close to these Points is presented through deriving small-signal model and transfer function of boost converter. This paper aims at modeling boost converter including equivalent series resistance of input reservoir capacitor by state-space-averaging method and PWM switch model. In the future, properly designed controller for compensation will be constructed in real system for maximum photovoltaic power tracking control.

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