• 한국환경과학회지
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• 제24권10호
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• pp.1239-1251
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• 2015

Impervious areas have been expanded by urbanization and the natural structure of water circulation has been destroyed. The limits of centralized management for controlling storm water runoff in urban areas have been suggested. Low impact development (LID) technologies have been promoted as a crucial alternative, establishing a connection with city development plans to build green infrastructures in environmentally friendly cities. Thus, the improvement of water circulation and the control of nonpoint source were simulated through XP-SWMM (storm water and wastewater management model for experts) in this study. The application of multiple LID combination practices with permeable pavements, bioretention cells, and gutter filters were observed as reducing the highest runoff volume by up to 70%. The results from four different LID installation scenarios indicated that permeable paving is the most effective method for reducing storm water runoff. The rate of storm water runoff volume reduced as the rainfall duration extended. Based on the simulation results, each LID facility was designed and constructed in the target area. The LID practices in an urban area enable future studies of the analysis of the criteria, suitable capacity, and cost-efficiency, and proper management methods of various LID techniques.

• 한국수자원학회논문집
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• 제36권5호
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• pp.725-740
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• 2003

도시화에 따라 인구집중과 광역화로 인하여 자연환경이 크게 변화하였으며, 특히 인간의 활동은 새로운 유출양상을 가져오는 원인이 되었다. 본 연구에서는 도시의 개발에 따른 도시화 전$\cdot$후의 지형인자가 변화함으로써 야기되는 유출변화 특성을 해석하였다. 도시화유역에서의 유출에 ILLUDAS 모형을 이용하였으며, 다음과 같은 결론을 얻었다. 도시화 전$\cdot$후의 첨두발생시간을 살펴보면, 약 15∼35 분 정도 단축되었으며, 도시화 후의 첨두홍수량은 최대 60 % 정도 증가함을 알 수 있었다.

• Environmental Engineering Research
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• 제25권4호
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• pp.545-553
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• 2020

Rainfall-Runoff modeling plays a crucial role in various aspects of water resource management. It helps significantly in resolving the issues related to flood control, protection of agricultural lands, etc. Various Machine learning and statistical-based algorithms have been used for this purpose. These techniques resulted in outcomes with an acceptable rate of success. One of the pertinent machine learning algorithms namely Adaptive Neuro Fuzzy Inference System (ANFIS) has been reported to be a very effective tool for the purpose. However, the computational complexity of ANFIS is a major hindrance in its application. In this paper, we resolved this problem of ANFIS by incorporating one of the evolutionary algorithms known as Particle Swarm Optimization (PSO) which was used in estimating the parameters pertaining to ANFIS. The results of the modified ANFIS were found to be satisfactory. The performance of this modified ANFIS is then compared with conventional ANFIS and another popular statistical modeling technique namely ARIMA model with respect to the forecasting of runoff. In the present investigation, it was found that proposed PSO-ANFIS performed better than ARIMA and conventional ANFIS with respect to the prediction accuracy of runoff.

• 방사성폐기물학회지
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• 제14권1호
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• pp.21-33
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• 2016

Estimation of groundwater hydrologic cycle pattern is one of the most critical issues in sustainable management of groundwater resources in coastal area. This study estimated groundwater percolation by using the water balance methodology and hydrogeological characteristics of land use and soil. Evapotranspiration was computed by using the Thornthwaite method, and surface runoff was determined by using the SCS-CN technique. Groundwater storage change was obtained as 229 mm/a (17.8% of the average annual rainfall, 1286 mm/a), with 693 mm/a (60.1%) of evapotranspiration and 124 mm/a (9.6%) of surface runoff. Rainfall and groundwater storage change was highly correlated, comparing with the relationships between rainfall and evapotranspiration, and between rainfall and surface runoff. This result indicates that groundwater storage change responds more sensitively to precipitation than evapotranspiration and surface runoff.

• 한국환경과학회지
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• 제24권4호
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• pp.505-514
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• 2015

The grid-based water balance of watershed scale was assessed in the mountainous area of Pyosun catchment in Jeju Island after analyzing precipitation, evapotranspiration, and runoff from January 2008 to December 2013. The existing results of direct runoff, evapotranspirtion, and groundwater recharge comparing to precipitation were presented 22.0%, 25.6%, and 52.4%, respectively, in Pyosun catchment. However, this study indicated each component shows 14.5%, 24.2%, and 61.0%, respectively, in the mountainous area of Pyosun catchment. Therefore, groundwater recharge rate in the mountainous area appears higher than 10% comparing to the overall catchment. It would be analyzed that the amount of direct runoff is relatively small. Moreover, this difference could be generated because of the spatial discontinuities in the process of estimating the total amount of precipitation in the mountainous area. Therefore, the grid-based spatial analysis to maximize the spatial continuity would be useful for providing a more reasonable result when the total amount of water resources are evaluated in mountainous areas in the future.

• 한국토양비료학회지
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• 제43권1호
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• pp.36-43
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• 2010

충남 공주 팔봉산 남쪽 측면에 위치한 3년간 배나무가 식재된 구릉성 침식포장에서 유거와 침식의 변화를 (1)Glyphosate 처리 (2) paraquat 처리의 두 가지 서로 다른 제초관리 형태하에서 조사하였다. 조사지의 경사도는 5.5% ~ 10.2%, 고도 125 m이며 조사면적은 896 $m^2$ ($28m{\times}32m$)였다. 2006년에서 2008년 사이 총강우사상은 각각 47, 52, 52회였다. 전체 강우사상 중 일 강우량이 20 mm보다 적은 날은 전체 강우일수의 약 65%를 차지하였다. 평형상태에서 침투율은 지표면의 잡초가 모두 제거된 나지에서 일반적으로 증가하였으며, 제초제처리구와 대조구에서는 감소하였다. 모든 대조구에서 유거는 제초제처리구와 나지구보다 항시 낮았다. 동일 강우강도에서 유거는 대조구, glyposate 처리구, paraquat 처리구 glyposate-처리 나지구 순으로 증가하였다. 높은 강우강도하에서 처리구가간 유거의 차이는 1년차에서 가장 높았다. 조사 기간 3년간 토양손실은 각각 달랐다. 미세입자 손실이 조립질보다 높았으나 토양손실은 유거나 총강우량과 상관성은 없는 것으로 조사되었다. 동일 강우강도하에서 토양침식율은 대조구, glyposate 처리구, paraquat 처리구 glyposate-처리 나지구 순으로 증가하였다. 상대적으로 30 mm 이하의 강우강도하에서는 조사구간 제초제 처리 여부 상관성이 거의 없었다. 이는 토양침식은 강우강도에 의존한다는 것을 의미한다.

• 한국수자원학회논문집
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• 제56권10호
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• pp.655-665
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• 2023

본 연구에서는 일정한 경사와 조도를 갖는 가상 유역에서 10가지 규모의 강수가 순간적으로 발생할 때 단위유량도를 산출하였다. 그런 다음 강수 규모에 대하여 단위유량도 첨두유량의 관계와 첨두발생시간의 관계를 각각 산출하였다. 이때 강수 규모만이 유역의 단위유량도 첨두치에 주는 영향을 파악하기 위해서 자연 유역을 대신하여 마름모 형태, 일정 경사, 일정 조도의 유로 환경 상태 등으로 단순화한 가상 유역을 적용하였다. 그리고 유역에 내린 강수는 유효우량이고 유출은 직접유출이고 낙하지점에서 출구 방향으로 직선적인 등류로 유출된다고 가정하였다. 강수 규모를 10가지로 유효강수 10 mm, 40 mm, 90 mm, 160 mm, 250 mm, 360 mm, 640 mm, 1,000 mm, 1,210 mm, 1,690 mm의 경우로 하여 단위유량도의 첨두유량과 첨두발생시간을 각각의 관계를 산출하였다. 본 연구에서 주목할 만한 성과는 유역의 저류 효과가 없어도 강수 규모가 커질수록 유출 깊이가 커져서 유역의 유속이 빨라지고 단위 시간당 유하 거리도 커지므로 첨두유량은 커지고 첨두발생시간은 빨라진다는 것이었다. 이는 유역 유출의 비선형적 특성이다.

• 한국농공학회지
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• 제18권3호
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• pp.4184-4194
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• 1976

Located in the southwestern part of Korea, the Yong San Gang river flows generally northeast to southwest, and because of the specific location, topography and climate, the basin area is subject to recurrent drought and flood damages. To eliminate the cause of such damages and ensure an increase in the farm income by means of effective irrigation supply and increased cropping intensity, efforts are being made to speed up implementation of an integrated agricultural development project which would include construction. of an estuary dam and irrigation facilities as well as land development and tidal reclarnation. In formulating a basin development project plan, it is necessary to study a series of long-term runoff data. The catchment area at the proposed estuary damsite is 3,471$\textrm{km}^2$ with the total length of the river channel up to this point reaching 138km. An analysis of runoff in this area was carried out. Rainfall was estimated by the Thiessen Network based on records available from 15 of the rainfall observation stations within the area. Out of the 15 stations, Kwang Ju and Mok Po stations were keeping long-term precipitation records exceeding some 60 years while the others were in possession of only 5-10 years records. The long-term records kept by those stations located in the center of the basin were used as base records and records kept by the remaining stations were supplemented using the coefficient of correlation between the records kept by the base stations and the remainder. The analyses indicate that the average annual rainfall measured at Kwang Ju during 1940-1972 (33 years) amounts to 1,262mm and the areal rainfall amounts to 1,236mm. For the purpose of runoff analysis, 7 observatories, were set up in the middle and lower reaches of the river and periodic measurements made by these stations permitted analysis of water levels and river flows. In particular, the long-term data available from Na Ju station significantly contributed to the analysis. The analysis, made by 4-stage Tank method, shows that the average annual runoff during 1940-1972 amounts to 2,189 million ㎥ at the runoff rate of 51%. As for the amount of monthly runoff, the maximum is 484.2 million ㎥ in July while the minimum is 48.3 million ㎥ in January.

• 한국도로학회논문집
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• 제11권3호
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• pp.141-149
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• 2009

본 연구는 고속도로 강우 유출수에서 입도 크기 분포 특성(PSD)을 이해하기 위하여 수행하였다. 경기도내 4곳의 포장도로 지역에서 2번의 강우사상동안 강우유출수 샘플 모니터링을 수행하였고, 시료내 입자의 크기분포를 분석하였다. 또한, 강우량, 유량 및 각 오염물질들을 분석하였다. 시료내 입자의 시간별 변화농도는 강우유출수의 시작 시 높은 값을 보였다가 급속히 감소하였으며 탁도, 총부유물질, BOD, 총질소 및 총인과 같은 오염물질과 유사한 유출경향을 보여주었다. 특히 총부유물질과 탁도와의 높은 상관성을 보여주었다. 강우유출수와 퇴적물내에 포함된 중금속에 있어서 구리, 납, 아연은 높은 농도를 보였으며 대부분의 중금속은 넓이에 대한 부피의 비율이 큰 세립입자에 강하게 결합된 형태로 존재한다.

• 상하수도학회지
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• 제27권3호
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• pp.299-312
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• 2013

This study investigated the contaminant loading and characteristics of particle size distributions(PSDs) in the rainfall runoff from two different sources, the pavement road and the ancillary parking lot, and then evaluated four different types of filter media(i.e., EPP, EPS, Zeolite, and Perlite) to treat runoff water. The results showed that runoff from the pavement road contains 5.6 and 20 times higher SS and Pb concentrations, respectively, than that from the parking lot. The particles smaller than $100{\mu}m$ occupied 89.8 % of runoff from the pavement road and 81.4 % of that from the parking lot by volume. The effect of the hydraulic loading, at 950 m/day filtering linar velocity and 40 cm head loss, was largest for Zeolite, followed by Perlite, EPS, and EPP. The return period of tested media calculated by the regression equation for head loss indicated that EPP has the longest life time. The average SS removal rate was similar for all media at between 84.9 % and 89 %, while the effect of various filter column heights was different, showing minimal for EPP and maximum for EPS. All filter media tested demonstrated over 95 % of SS treatment efficiency for the particles bigger than $100{\mu}m$, while for the ones smaller than $100{\mu}m$ the efficiency was in order of EPP(82.4%) > Perlite(76.1 %) > EPS(66.2 %) > Zeolite(65.2 %). The results in conclusion implies that EPP is most effective filter media for the highly contaminated fine particles from road runoff.