• 한국수자원학회논문집
• /
• 제36권6호
• /
• pp.1097-1107
• /
• 2003

개념적 집중형 일 유출모형인 DAWAST모형을 선정하여 용수수요를 고려할 수 있는 가능성을 검토하였다. 기존 모형에 의한 모의 유량을 자연유량으로 보았고, 농업용수, 생활용수, 공업용수 등 회귀수량을 더한 값을 하천유량으로 가정하였다. 농업용수의 수요량은 회귀수량이 논으로부터만 발생하는 것으로 보아 논 용수량만을 고려하였으며, 수정 Penman공식에 의한 증발산량, 침투량, 재배관리수량, 유효우량 등을 고려한 일별 감수심에 의해 일별로 계산하였다. 생활용수, 공업용수 수요량은 일 평균값에 월별 변동계수를 고려하여 일별로 계산하였다. 신뢰도가 높은 대청댐 운영실적의 유입량 자료를 이용하여 용수수요를 고려한 DAWAST 모형의 적용성을 평가하였다. 농업용수의 회귀율은 35%, 생공용수의 회귀율은 65% 적용하였으며, 1983년∼2001년 연평균하여 강우량 1184.6 mm 관측 유입량 667.3 mm 모의 유입량 652.6 mm 로 용수수요를 고려하지 않은 경우의 모의 유입량 606.8 mm에 비해 45.8 mm 가 높게 나타났으며, 모의/관측 유입량 비율도 90.9 % 에서 97.8% 로 개선되는 결과를 얻었다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 1998년도 학술발표회 발표논문집
• /
• pp.8-13
• /
• 1998

DAWAST model considering the meteorologic and geographic characteristics of the Korean watersheds was newly developed to simulate the daily streamflow. From the condition of soil water storage just before the storm event from DAWAST model, realtime flood can be forecasted by FLOCON model. The purpose of study is that Umax and FC of DAWAST model parameter is obtained by the soil physical characteristics.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 1998년도 학술발표회 논문집
• /
• pp.239-244
• /
• 1998

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2003년도 학술발표논문집
• /
• pp.503-506
• /
• 2003

The DAWAST model was originally developed to consider daily variation in the unsaturated soil water storage and it is a conceptual lumped model. Return flows from agricultural, domestic and industrial water were included to the original result of model simulation to calibrate model parameter. Daily inflow to the Daechung multipurpose dam was applied to verify the DAWAST model considered return flows. Simulation results were comparable to the inflows of dam operation reasonably.

• 한국농공학회지
• /
• 제43권2호
• /
• pp.78-84
• /
• 2001

The daily streamflow in the Yaluhe watershed located in the north-eastern part of China was simulated by DAWAST model and the water balance parameters of the model were calibrated by simplex method. Model verification tests were carried out. The range of root mean square error was 0.34∼1.50mm, that of percent error in volume was -16.9∼-62.0% and that of correlation coefficient was 0.727∼0.920. DAWAST model was revised to consider the phreatic evaporation from the ground water in the frozen soil by adjusting soil moisture content in the unsaturated layer at the end of the melting season. The results of estimation of the daily streamflow by the revised model were statistically improved, that is, the range of root mean square error was 0.31∼1.49mm, that of percent error in volume was -11.7∼-12.1%, and that of correlation coefficient was 0.810∼0.932. The accuracy of DAWAST model was improved and the applicability of DAWAST model was expanded to the frozen region.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
• /
• pp.57-62
• /
• 1999

The study has been performed to estimated the quantity of ground water recharge using the DAWAST model for water balance analysis in the Youngsan & Sumjin watersheds. The mean safe yield of ground water is annually 41.3mm, corresponding to 85 $\times$106 ㎥ at the Naju station in the Youngsan watershed, and 76.6mm corresponding to 343 $\times$ 106 ㎥ at the Songjung station in the Sumjin watershed. It is remarkable because safe yield of ground water are estimated 44 to 64 % less than the quantities estimated in the other researches.

• 농업과학연구
• /
• 제38권3호
• /
• pp.513-524
• /
• 2011

To evaluate the applicability of inflow runoff model to reservoir operation in Korea, DAWAST model and TPHM model which are conceptual lumped daily runoff model and were developed in Korea, were selected and applied to simulate inflows to Daecheong multipurpose dam with watershed area of 4,134 $km^2$, and water storages in Geryong reservoir with watershed area of 15.1 $km^2$ and total water storage of 3.4 M $m^3$. Evaluating inflows on an yearly, monthly, ten-day, and daily basis, inflows by DAWAST model showed balanced scatters around equal value line. But inflow by TPHM model showed high in high flows. Annual mean water balance by DAWAST model was rainfall of 1,159.9 mm, evapotranspiration of 622.1 mm, and inflow of 644.6 mm, from which rainfall was 104.8 mm less than sum of evapotranspiration and inflow, and showed unbalanced result. Water balance by TPHM model showed satisfactory result. Reservoir water storages were shown to simulate on a considerable level from applying DAWAST and TPHM models to simulate inflows to Geryong reservoir. But it was concluded to be needed to improve DAWAST and TPHM model together from imbalance of water balance and low estimation in high flow.

• 한국농공학회지
• /
• 제33권4호
• /
• pp.61-72
• /
• 1991

A lumped deterministic model(DAWAST model) was developed to predict the daily streamflow. Since the streamflow is dominantly determined by the soil water storage in the watershed, the model takes the soil water accounting procedures which are based on three linear reservoirs representing the surface, unsaturated, and saturated soil layers. The variation of soil water storage in the unsaturated zone is traced from the soil water balance on a daily basis. DAWAST model consists of 5 parameters for water balance and 3 parameters for routing. A optimization technique of unconstrained nonlinear Simplex method was applied for the determination of the optimal parameters for water balance. Model verification was carried out to the 7 hydrologic watersheds with areas of 5.89-7,126km$^2$ and the results were generally satisfactory. The daily streamflow can be arbitrarily simulated with the input data of daily rainfall and pan evaporation by the DAWAST model at the station where the observed streamflow data of short periods are available to calibrate the model parameters.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2002년도 학술발표회 발표논문집
• /
• pp.249-252
• /
• 2002

This model is the daily streamflow model of the Korean watersheds has been developed to simulate the daily streamflow with the data of daily rainfall and pan evaporation. Parameters of this model are the water balance parameters composed Umax, Lmax, FC, CP, and CE and the routing parameters composed $U_i,\;k_1\;and\;k_2$. Among these parameters, CE value is applied one fixed value during the year and coefficient of initial ion K is empirically determined by 0.2. The object of this research is to improve the DAWAST model by application of the monthly value of CE for evapotranspiration and the revised K value for the initial abstraction.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2001년도 학술발표회 발표논문집
• /
• pp.456-459
• /
• 2001

A relationship between the water quantity and the inflow pollutant loads of BOD, TN, and TP in So-okcheon of the upper Keum river in 2000 was investigated in this study. Daily streamflow of So-okcheon needed to compute the pollutant loads was estimated by the DAWAST model, because there is no measurement of the discharge. From a relative function of the inflow pollutant loads using DAWAST, BOD can be estimated by the relation of $y=145.31x^{1.06},\;TN\;by\;y=598.11x^{0.90}\;and\;TP\;by\;y=39.60x^{0.89}$.