• 한국농공학회논문집
• /
• 제54권2호
• /
• pp.67-75
• /
• 2012

Different from other natural hazards including floods, drought advances slowly and spreads widely, so that the preparedness is quite important and effective to mitigate the impacts from drought. Evaluation and forecast the status of drought for the present and future utilizing the meteorological scenario for agricultural drought can be useful to set a plan for agricultural drought mitigation in agriculture water resource management. In this study, drought climate scenario model on the basis of historical drought records for preparing agricultural drought mitigation was developed. To consider dependency and correlation between various climate variables, this model was utilized the historical climate pattern using reference year setting of four drought levels. The reference year for drought level was determined based on the frequency analysis result of monthly effective rainfall. On the basis of this model, drought climate scenarios at Suwon and Icheon station were set up and these scenarios were applied on the water balance simulation of reservoir water storage for Madun reservoir as well as the soil moisture model for Gosam reservoir watershed. The results showed that drought climate scenarios in this study could be more useful for long-term forecast of longer than 2~3 months period rather than short-term forecast of below one month.

• 상하수도학회지
• /
• 제35권1호
• /
• pp.15-25
• /
• 2021

In this study, a method of leakage detection was proposed to locate leak position for a reservoir pipeline valve system using wavelet coherence analysis for an injected pressure wave. An unsteady flow analyzer handled nonlinear valve maneuver and corresponding experimental result were compared. Time series of pressure head were analyzed through wavelet coherence analysis both for no leak and leak conditions. The leak information can be obtained through either time domain reflectometry or the difference in wavelet coherence level, which provide predictions in terms of leak location. The reconstructed pressure signal facilitates the identification of leak presence comparing with existing wavelet coherence analysis.

• The Korean Journal of Ecology
• /
• 제22권5호
• /
• pp.235-240
• /
• 1999

토지이용이 어떻게 수질에 영향을 주는가를 연구하고자 1993년 3월 부터 1998년 3월 까지 조사를 실시하였다. 조사지는 충북 옥천군 이원면의 경작지가 주류를 이루는 개심저수지와 산지유역으로 특성지워지는 장찬저수지 유역을 대상으로 하였다. 조사유역을 11개 소집수역으로 세분하고 토지이용과 하천수질과의 상관성, 하천 유역의 오염원 동태를 생태학적 관점에서 규명하고자 조사를 실시하였다. BOD, SS, TKN은 하류로 갈수록 높아졌으나 자정 한계를 넘어선 G 소집수역은 예외였다. 장찬저수지 유역은 가두리 양식장 때문에 수질이 악화되어 있는 것으로 나타나 양식장의 폐쇄가 시급한 것으로 조사되었다. .해발표고는 200 m 이하가 개심저수지 유역 56.0%, 장찬저수지 유역 44.0%로 대부분을 차지하였다. 비삼림지역은 전체 조사면적 44.91 ㎢중 14.74 ㎢로 32.8%를 차지하였는데 특히 경작지와 주거지 면적 비의 증가에 따라 총인(Y=0.2023X＋0.0991, r=0.54)이 증가되고 있다. 토지이용별 오염 배출원 단위가 수질에 미치는 영향을 분석한 결과 농경지의 오염부하량은 매우 크며 비점오염물질이 하천에 유입, 유하 하는 동안 물리, 화학, 생화학적, 생물학적 변화를 거쳐 농도가 낮아지고 있다. 그러나 삼림지역의 오염부하량은 농경지의 오염부하량 보다는 상대적으로 작으나 오히려 하천으로 유입, 유하하는 동안 오염 물질의 양이 높아졌다.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2002년도 추계학술발표회
• /
• pp.13-16
• /
• 2002

The analysis of characteristics of pumping in the small tube well for agriculture were surveyed. Study area was located at the Galsinri in Yesangun near the yedang reservoir. Agricultural electricity using rates for pumping, ground water level and volume of pumping was monitored every week. Pump working ratio and pump efficiency during period of transplanting of rice showed 48.9%, 62.7% respectively.

• 지질공학
• /
• 제26권2호
• /
• pp.251-260
• /
• 2016

댐 저수지의 높은 수위와 댐 외부 지역의 지하수위간의 수두 차이는 지질 방벽을 통한 물의 흐름을 발생시킨다. 이로 인하여 발생한 유역 외 지역의 얕은 지하수위는 토양 습윤화를 초래하여 토지이용에 제약을 가져온다. 본 연구에서는 습윤화가 진행된 소유역내에 지하 1~1.5 m 심도에서 유공관 등의 배수시설을 설치한 후 그 효과를 분석하였다. 배수시설 설치 이전에 비하여 지하수 관측정에서의 수위는 1 m 이상 하강한 것으로 나타났으며, 저수지와 인접한 골짜기 상류(W1 지점)의 경우에는 2m 이상 하강하여 지하수의 빠른 배출에 의한 효과가 발생하였다. 또한, 지역 내 토양수분함량 및 그 표준편차도 감소하여 배수시설에 의한 지하수위 하강이 토양 습윤화를 억제한 것으로 분석되었다. 댐의 설계 시에는 지형지리적 특성을 고려하여 수두 차이에 의한 외부 지역으로의 누수 현상 예측 및 관련 대책을 수립해 나가야 한다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2001년도 학술발표회 발표논문집
• /
• pp.30-33
• /
• 2001

This study was carried out to estimate the runoff pollutant loadings for water quality management in Boryung freshwater reservoir watershed. The hydrological monitoring system were operated for water level measurement during $1999{\sim}2000$ and temporal variation of water quality constituents such as pH, EC, total nitrogen, total phosphorus were analysed, periodically. Monthly runoff volumes by TANK model and potential pollutant loadings calculated by unit method were compared with measured values.

• 한국농공학회논문집
• /
• 제62권2호
• /
• pp.111-120
• /
• 2020

This study assessed the reliability of the agricultural water supply based on future climate change scenarios, and suggested plans to improve the reliability in order to promote the adaptability of irrigation water in agricultural reservoirs to climate change. The assessment of agricultural water supply reliability was performed on reservoirs which had a lower water quantity than their design basis and which had recently been subject to drought. In other words, from the irrigation districts of main intake works among the reservoirs managed by the Korea Rural Community Corporation, 1~2 districts in each province-that is, a total of 13 districts -that were recently designated as a district for securing agricultural water (drought prevention district) were selected. Climate change scenarios were applied to the selected districts to analyze their future water supply reliability compared to the current level. All districts selected showed a drought frequency of 4 years or shorter, which demonstrated the need to establish climate change response plans. As plans for responding to climate change, a plan that utilizes supplemental intake works to reduce the area of the irrigation districts of main intake works, and another one that increases the capacity of main intake works were adopted to reanalyze their water supply reliability. When the area of the irrigation districts of main intake works was reduced by about 30~40%, the drought frequency dropped to more than 10 years, securing the reliability of water supply. To secure the reliability by increasing the capacity of main intake works, it was calculated that about 19,000~2,400,000 tons need to be added to each reservoir. In addition, climate change response plans were suggested to improve the reliability of the water supply in each district based on the results of economic analysis.

• 한국농공학회논문집
• /
• 제53권6호
• /
• pp.165-170
• /
• 2011

Recently natural disasters such as the frequency and intensity of drought have been increasing as a result of climate change. This study suggests a drought index, WADI (Water Availability Drought Index), that considers water availability using 6 components (water intake, groundwater level, agricultural reservoir water level, dam inflow, streamflow, and precipitation) using the Z score and data monitoring on a nationwide level. SPI (Standardized Precipitation Index) was applied in coastal area. For the severe droughts of 2001 spring and 2008 autumn, the index was evaluated by comparison with reported damage areas. suggested to combine The spatial concordance rate of WADI in 2001 and 2008 for estimation of the degree of drought severity was 50 % and 24 % compared to the actual recorded data respectively.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 D
• /
• pp.784-786
• /
• 1997

In this Paper, the effective method of determining the water discharge of a pondage hydro-unit for hydro dispatch is proposed. The water discharge of a pondage hydro-unit can be determined subtracting the spillage discharge from summation of the inflow and the pondage according to variation of the water level of the reservoir. Proposed method calculates the inflow using the duration curve, the water level from initial level on January 1, and the spillage discharge from the water discharge.

• 한국농공학회지
• /
• 제42권
• /
• pp.24-30
• /
• 2000

A system for evaluating streamflow data (KORSAS) was developed, and is operated using PC based Windows to help the hydrological observation practitioner's working in Korea Water Resources Corporation (KOWACO). This system has modules including; DB access and data management, flow measurement arranging, H-Q relation deriving, area rainfall calculating, flow calculating, and flow evaluating modules. Evaluation of observed streamflow is accomplished through the following processes. First, hourly streamflow data is calculated from water level data stored in a DB server by applying the rating relationship between water level and flow rates derived from the past flow measurements. Second, hourly areal rainfal data is calculated from point data stored in the DB server by applying Thiessen networks. Third, hydrographs are displayed on a daily, weekly, monthly, or seasonal duration basis, and are compared to hydrographs of reservoir inflow, hydrographs at water level observation stations and hydrographs derived from simulated results using models.