Auto-calibration for the SWAT Model Hydrological Parameters Using Multi-objective Optimization Method
최지용 Choi Ji Yong , 강문성 Kang Moon Seong , 박승우 Park Seung Woo , 김학관 Kim Hak Kwan , 양희정 Yang Hee Jeong
51(1) 1-9, 2009
Auto-calibration for the SWAT Model Hydrological Parameters Using Multi-objective Optimization Method
최지용 Choi Ji Yong , 강문성 Kang Moon Seong , 박승우 Park Seung Woo , 김학관 Kim Hak Kwan , 양희정 Yang Hee Jeong
DOI: JKWST Vol.51(No.1) 1-9, 2009
The objective of this paper was to evaluate the auto-calibration with multi-objective optimization method to calibrate the parameters of the Soil and Water Assessment Tool (SWAT) model. The model was calibrated and validated by using nine years (1996-2004) of measured data for the 384-ha Baran reservoir subwatershed located in central Korea. Multi-objective optimization was performed for sixteen parameters related to runoff. The parameters were modified by the replacement or addition of an absolute change. The root mean square error (RMSE), relative mean absolute error (RMAE), Nash-Sutcliffe efficiency index (EI), determination coefficient (R2) were used to evaluate the results of calibration and validation. The statistics of RMSE, RMAE, EI, and R2 were 4.66 mm/day, 0.53 mm/day 0.86, and 0.89 for the calibration period and 3.98 mm/day, 0.51 mm/day, 0.83, and 0.84 for the validation period respectively. The statistical parameters indicated that the model provided a reasonable estimation of the runoff at the study watershed. This result was illustrated with a multi-objective optimization for the flow at an observation site within the Baran reservoir watershed.
Soil-Water Characteristic Curve of Weathered Granite Soils in Pocheon Area using Flow Pump Technique
이강일 Lee Kang Il , 이준용 Lee Joon Yong , 백원진 Back Won Jin
51(1) 11-20, 2009
Soil-Water Characteristic Curve of Weathered Granite Soils in Pocheon Area using Flow Pump Technique
이강일 Lee Kang Il , 이준용 Lee Joon Yong , 백원진 Back Won Jin
DOI: JKWST Vol.51(No.1) 11-20, 2009
Flow pump technique was used in order to determine the soil-water characteristic curve of weathered granite soils in Pocheon area. This technique enables measurement to be more convenient and accurate as it is based on the CU condition of triaxial compression test. Besides, it is also able to measure dry and moisture curves continuously since the test is controled by means of a computer automatically. In this study, not only a hydraulic conductivity of weathered granite soils at fully saturated state in Pocheon area, but also a soil-water characteristic curve throughout unsaturate flow tests were determined. In addition, Brooks and Corey's model and Genuchten's model were used to simulate the soil-water characteristic curve. On the basis of the simulation an unsaturate hydraulic conductivity was predicted.
Physical and Mechanical Properties of Concrete Using Waste Activated Carbon
강현수 Kang Hyun Soo , 성찬용 Sung Chan Yong
51(1) 21-26, 2009
Physical and Mechanical Properties of Concrete Using Waste Activated Carbon
강현수 Kang Hyun Soo , 성찬용 Sung Chan Yong
DOI: JKWST Vol.51(No.1) 21-26, 2009
This study was performed to evaluate the physical and mechanical properies of concrete using waste activated carbon. Materials used were ordinary portlant cement, crushed coarse aggregate, natural fine aggregate, waste activated carbon, and superplasticizer. The substitution ratios of waste activated carbon were 0,1,2,3,4,5,6,7,8,9 and 10%. The unit weight was decreased and water absorption ratio was increased with increasing the waste activated carbon content, respectively. When the substitution ratio of waste activated carbon was 3%, compressive strength, flexural strength and dynamic modulus of elastisity were more higher than that of the ordinary portland cement (OPC), and it was decreased with increasing the waste activated carbon content, respectively. The most effective contents of waste activated carbon was 2% in performance and 4% in practical use Accordingly, waste activated carbon can be used for concrete material.
Feasibility Study of Wastewater Reuse for the Vegetable Farming in Jejudo
성충현 Seong Choung Hyun , 강문성 Kang Moon Seong , 장태일 Jang Tae Il , 박승우 Park Seung Woo , 이광야 Lee Kwang Ya , 김해도 Kim Hae Do
51(1) 27-32, 2009
Feasibility Study of Wastewater Reuse for the Vegetable Farming in Jejudo
성충현 Seong Choung Hyun , 강문성 Kang Moon Seong , 장태일 Jang Tae Il , 박승우 Park Seung Woo , 이광야 Lee Kwang Ya , 김해도 Kim Hae Do
DOI: JKWST Vol.51(No.1) 27-32, 2009
The objective of this study is to assess the feasibility of wastewater reuse for the vegetable farming. The study region, about 250 ha in size, is located on the west coast of Jejudo, Korea. Major agricultural products of the study area are the cabbage, broccoli, garlic and onion. To confirm the feasibility of wastewater reuse, the drought duration and the water requirement analysis were conducted respectively. The average annual precipitation of the study region (1,121 mm) was smaller than that of Jeju island (1,975 mm). The drought duration for a ten-year return period in October through November was more than 20 days. The water requirement for irrigation was calculated by the FAQ Penman-Monteith method which took into account the cultivated crops, planting system, and meteorological conditions of the study region. The water requirement for a ten-year return period was estimated 4.7 mm/day and the water demand for irrigation was 4,584 ㎥/day. As a result, the irrigation water for the crops was insufficient during their breeding season, especially in October through November. Thus, the result indicated that the study region required the alternative water supply such as wastewater reuse during the non-rainy season. As drought continues to place considerable stress on the availability of fresh water supplies in the study region, irrigation with reclaimed wastewater will play an important role in helping to meet future water demands.
The Improvement of Water Quality Purification through the Effective Management of Fallow Paddy Fields
지용근 Jee Yong Keun , 김선주 Kim Sun Joo , 김필식 Kim Phil Shik
51(1) 33-39, 2009
The Improvement of Water Quality Purification through the Effective Management of Fallow Paddy Fields
지용근 Jee Yong Keun , 김선주 Kim Sun Joo , 김필식 Kim Phil Shik
DOI: JKWST Vol.51(No.1) 33-39, 2009
A number of fallow paddies field continues to increase because of adverse agricultural circumstance such as upsurge income of foreign products, increase of labor costs in local community, imbalance between productivity and profitability etc. Such fallow paddies are necessary to be protected against weeds and trees. If fallow paddies are not managed, it will be devastated and needed cost for re-cultivation. Therefore, management of gradually increased fallow paddy fields should be conducted. In this study, the effect of plants growth inhibition and water quality purification through the control of flood in fallow paddy were examined in an experimental field. The managed and unmanaged fallow paddies through the control of water depth were constructed in the experimental field. The monitoring was conducted from 2005 to 2007. As the result, the managed fallow paddies were more effective than the unmanaged ones on the growth inhibition and water purification. In addition, when the fallow paddy is managed with regular water depth, it was the most effective in the plants growth inhibition.
