• 대한토목학회논문집
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• 제33권2호
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• pp.521-528
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• 2013

일반적으로 도시배수 시스템은 개수로 흐름으로 설계 된다. 그러나 설계빈도를 초과하는 강우발생 시 배수 시스템의 합류부 또는 맨홀 등에서 부분적인 과부하 흐름이 발생되고 있다. 그러므로 이와 같은 과부하 흐름에 의해 발생하는 배수 시스템에서의 압력흐름에 대한 연구의 필요성이 제기 되고 있다. 따라서 본 연구에서는 설계빈도를 초과 하는 강우사상 그리고 예측할 수 없는 집중호우 시 맨홀에서의 과부하 흐름에 관한 연구를 수행 하였다. 배수 시스템에서의 압력흐름의 문제점은 과부하 맨홀로부터의 월류량에 의한 도시홍수 발생이다. 그러므로 배수 시스템은 개수로 흐름으로 설계 되어야 할 뿐만 아니라 과부하 흐름 발생 시 맨홀내의 에너지 손실을 고려한 압력흐름의 해석이 필요하다. 따라서 본 연구에서는 과부하 맨홀의 에너지 손실을 고려하여 압력흐름을 해석 할 수 있는 수치모형을 개발하였다. 수치모형을 검증하기 위하여 수리모형실험 결과와 비교 검증하였고, 도시유출해석에 가장 널리 이용되는 SWMM의 결과와도 비교하였다. SWMM은 맨홀 내의 에너지 손실을 적절히 반영하지 못함으로써 맨홀 수심을 과소 산정하는 결과를 보인 반면, 본 연구 모형은 수리모형실험결과와 잘 일치하였다.

• 한국농공학회지
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• 제35권3호
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• pp.23-35
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• 1993

The objectives of this paper were to validate the proposed network flow model using field data and to demonstrate the model applicability for various purposes. The model was tested with data from the Banweol watershed, where an intentive streamflow gauging system has been established. Model parameters were not calibrated with field data so that it can be validated as ungaged conditions. Three different schemes were employed to represent the drainage system of the tested watershed : a single, complex, and detailed network. The single network assumed the watershed as a cell, while complex and detailed networks considered several cells. The results from different schemes were individually compared satisfactorily to the observed daily stages at the Banweol reservoir located at the outlet of the watershed. The results from three schemes were in close agreement with each other, Justifying that the model performs very well for different network schemes being used. Daily streamflow from three network schemes was compared for a selected reach within the watershed. The results were very close to each other regardless of network formulation. And the model was applied to simulate daily streamflow before and after the construction of a reservoir at a reach. The differences were discussed, which reflected the influences of the dam construction upon the downstream hydrology. Similar appliocations may be possible to identify the effects of hydraulic structures on streamflow.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2000년도 추계학술발표논문집
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• pp.115-115
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• 2000

제지 공정의 효율적인 운영을 위해 공정변수를 확인하는 작업은 매우 중요하다. 탈수 특성 평가를 위하여 SR(Shopper- RegIer)과 CSF(Canadian Standard Freeness tester) 그리고 원형 수초지기 동의 비난류 상태의 자연탈수 특성 평가 장치와 동적 조건의 감압식 탈수성 분석기 퉁이 도입되어 있으나 제지 공정에 보다 더 근접한 탈수, 보류 특성을 평가 하기 위하여 특히 wet-end 첨가제들의 효능을 보다 정확히 분석할 수 있도록 난휴 발생과 감압 탈수 둥을 유도한 탈수 특성 평가 장치 개발의 필요성이 커지고 있다Il, 2) 이미 소개된 RDA-HSF

• 상하수도학회지
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• 제13권1호
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• pp.43-50
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• 1999

In spite of low energy requirement, and operation and construction cost, biofilters with soil beds have not been operated efficiently. Because of excess moisture in winter and rainy periods, saturated pores in the bed prevent passage and sorption of odorous compounds. Sometimes this results in septic conditions that release previously sorbed and oxidized sulfur. Therefore, an economical and effective alternative needs to be developed. The objectives of this study were to confirm applicability of the granular scrap tires with compost for treating odorous gas as well as to obtain optimum design parameters for proposed system. In lab-scaled test, multiple stage reactors had lower headloss than a single stage reactor and less headloss was occurred for the gas with higher moisture content. For practical purpose, pilot-scaled reactor was operated to remove odor from septic tank, manure and animal wastewater treatment plant and composting machine. According to the results of pilot scaled test, $H_2S$ can be always removed completely and ammonia/amine can be removed excellently when proper moisture content is provided. The results from lab and pilot test showed that granular scrap tire could be replaced with soil as supporting material for biofilter showed excellent drainage because of its ability to reject moisture.

• 환경영향평가
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• 제19권5호
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• pp.475-481
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• 2010

Lots of pollutants typically originating from urban transportation are accumulating on the paved surfaces during dry periods and are washed-off directly to the river during a storm. Also, paved surfaces are contributing to increase in peak flows and volume of stormwater flows. These are the main reasons why the water quality of rivers and lakes remain polluted and still below standards. Currently, several management practices are being applied in developed countries but the design standards are still lacking. This research was conducted to develop a treatment technology that can be useful to address the problems concerning runoff quality and quantity. A lab scale infiltration device consisting of a pretreatment tank and media zone was designed and tested for various flow regimes characterizing the low, average and high intensity rainfall. Based on the experiments, the high intensity flow resulted to increase in outflow event mean concentration (EMC) of pollutants, about twice as much as the average outflow EMC. However, 78 to 88% of the total suspended solids were captured and retained in the pretreatment tank because of sedimentation. The removal of heavy metals such as zinc and lead was greatly affected by the vertical placement of woodchip layer prior to the media zone. It was observed that the high carbon content (almost 50%) in the woodchip provided opportunity for enhancing its uptake of metal by adsorption. The findings implied that the reduction of pollutants can be greatly achieved by means of proper pretreatment to allow for settling of particles with a combination of using high carbon source media like woodchip and a geotextile mat to reduce the flow before filtering into the media zone and finally discharging to the drainage system.

• 한국농공학회논문집
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• 제62권4호
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• pp.1-12
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• 2020

The extreme 2017 spring drought affected a large portion of South Korea in the Southern Gyeonggi-do and Chungcheongnam-do districts. This drought event was one of the climatologically driest spring seasons over the 1961-2016 period of record. It was characterized by exceptionally low reservoir water levels, with the average water level being 36% lower over most of western South Korea. In this study, we consider drought response methods to alleviate the shortage of agricultural water in times of drought. It could be to store water from a stream into a reservoir. There is a cyclical method for reusing water supplied from a reservoir into streams through drainage. We intended to present a decision-making plan for water supply based on the calculation of the quantity of water supply and leakage. We compared the rainfall-runoff equation with the TANK model, which is a long-term run-off model. Estimations of reservoir inflow during non-irrigation seasons applied to the Madun, Daesa, and Pungjeon reservoirs. We applied the run-off flow to the last 30 years of rainfall data to estimate reservoir storage. We calculated the available water in the river during the non-irrigation season. The daily average inflow from 2003 to 2018 was calculated from October to April. Simulation results show that an average of 67,000 tons of water is obtained during the non-irrigation season. The report shows that about 53,000 tons of water are available except during the winter season from December to February. The Madun Reservoir began in early October with a 10 percent storage rate. In the starting ratio, a simulated rate of 4 K, 6 K, and 8 K tons is predicted to be 44%, 50%, and 60%. We can estimate the amount of water needed and the timing of water pump operations during the non-irrigation season that focuses on fresh water reservoirs and improve decision making for efficient water supplies.

• 한국농공학회논문집
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• 제58권3호
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• pp.71-80
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• 2016

The component-based modeling framework for agricultural water-resources management (COMFARM) is a user-friendly, highly interoperable, lightweight modeling framework that supports the development of watershed-specific domain components. The objective of this study was to evaluate the suitability of the COMFARM for the design and creation of a component-based modeling system of agricultural reservoir watersheds. A case study that focused on a particular modeling system was conducted on a watershed that includes the Daehwa and Dangwol serial irrigation reservoirs. The hydrologic modeling system for the study area was constructed with linkable components, including the modified Tank, an agricultural water supply and drainage model, and a reservoir water balance model. The model parameters were each calibrated for two years, based on observed reservoir water levels. The simulated results were in good agreement with the observed data. In addition, the applicability of the COMFARM was evaluated for regions where reservoir outflows, including not only spillway release but also return flow by irrigation water supply, substantially affect the downstream river discharge. The COMFARM could help to develop effective water-management measures by allowing the construction of a modeling system and evaluation of multiple operational scenarios customized for a specific watershed.

• 농촌계획
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• 제20권2호
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• pp.103-114
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• 2014

The objective of this study was to develop agricultural reservoir water supply simulation system to assess water cycle of agricultural water district. Developed system was named as ARWS (Agricultural Reservoir Water supply simulation System). ARWS consists of platform and independent modules. In ARWS, reservoir inflow was calculated using Tank model, and agricultural water supply was calculated considering current farming period and mid-summer drainage. ARWS was applied to simulate water level of Gopung and Tapjung reservoir in 2011 - 2012. The results were compared to simulation results of HOMWRS and observed data. Average $R^2$, EI, RMSE of ARWS were 0.76, 0.46, 1.78 (m), average $R^2$, EI, RMSE of HOMRWS were 0.88, -0.14, 2.37 (m) respectively. Considering statistical variances, water level simulation results of ARWS were more similar to observed data than HOMWRS. ARWS can be useful to estimate reservoir water supply and assess hydrological processes of agricultural water district.

• 지질공학
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• 제9권1호
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• pp.1-15
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• 1999

여름철 집중강우시 발생하는 공주 송산리고분군의 누수 원인을 분석하기 위하여 인공함양시험을 실시하였다. 함양시험을 모사하는 2차원 불포화 지하수 유동 모델을 개발하고, 시험 중 측정한 관측정 수위와 함양량의 변화를 이용하여 모델변수의 보정을 수행하였으며 보정된 모델변수에 의하여 함양시험 모사를 실시하였다. 함양시험 및 모사 결과 고분군 누수현상의 주된 원인은 고분군 상부의 누수방지층에 발생한 균열을 통한 지하수의 직접적인 유입에 의한 것으로 분석되었다. 장기간 강우가 지속될 경우 고분군 북측의 원지반으로부터 불포화대를 통한 지하수의 유입 가능성이 존재하나 고분군 북측 벽체에 10% 내외의 유효포화도 증가만을 일으킬 것으로 정류상태 모사를 통하여 분석되었다. 따라서 고분군 누수 방지를 위한 대책으로는 트렌치에 의한 유도배수시설보다는 효과적인 누수방지층의 보강이 더 시급한 것으로 판단된다.

• 농촌계획
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• 제18권3호
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• pp.103-110
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• 2012

This study aims to find out the geographical distribution, the physical structure and characteristic of Gudle-jang Paddy-field in Cheongsando. On the basis of this study, the potential value and the assignment for the preservation of Gudle-jang Paddy-field were suggested. Gudle-jang Paddy-field is centrally distributed to Cheongsando and has various features as follows. First, it has the Ondol structure which is used Gudle-jang. Second, it has an irrigation canal which has functions of the tank and the prevention of cold-weather damage as well as the irrigation and drainage canal. The values of Gudle-jang Paddy-field are as follows; 1) It is the peculiar and inherent agricultural structure which is only found in Cheongsando. 2) It is the structure that the agricultural civil engineering and the agricultural water management technique of traditional methode are applied. 3) It has the worths of the traditional culture of Korea. 4) It is the important resource creating superb rural landscape of the region. In spite of these values of Gudle-jang Paddy-field, there were little efforts to preserve it. From now on, it is needed to form of sympathy about the value of Gudle-jang Paddy-field and to make efforts for preservation of it. Also the institutional and political strategy should be provided to preserve and manage Gudle-jang Paddy-field.