• 한국농공학회지
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• 제44권5호
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• pp.96-105
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• 2002

As an useful water purification system for non-point source pollution in rural watersheds, interests in constructed wetlands are growing at home and abroad. It is well known that constructed wetlands are easily installed, no special managemental needs, and more flexible at fluctuating influent loads. They have a capacity for purification against nutrient materials such as phosphorus and nitrogen causing eutrophication of lentic water bodies. The Constructed Wetland Design Model (CWDM), developed through this study is consisted mainly of Database System, Runoff-discharge Prediction Submodel, Water Quality Prediction Submodel, and Area Assessment Submodel. The Database System includes data of watershed, discharge, water quality, pollution source, and design factors for the constructed wetland. It supplies data when predicting water quality and calculating the required areas of constructed wetlands. For the assessment of design flow, the GWLF (Generalized Watershed Loading Function) is used, and for water quality prediction in streams estimating influent pollutant load, Water Quality Prediction Submodel, that is a submodel of DSS-WQMRA model developed by previous works is amended. The calculation of the required areas of constructed wetlands is achieved using effluent target concentrations and area calculation equations that developed from the monitoring results in the United States. The CWDM is applied to Bokha watershed to appraise its application by assessing design flow and predicting water quality. Its application is performed through two calculations: one is to achieve each target effluent concentrations of BOD, SS, T-N and T-P, the other is to achieve overall target effluent concentrations. To prove the validity of the model, a comparison of unit removal rates between the calculated one from this study and the monitoring result from existing wetlands in Korea, Japan and United States was made. As a result, the CWDM could be very useful design tool for the constructed wetland in rural watersheds and for the non-point source pollution management.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.497-500
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• 2001

Constructed wetlands are among the recently proven efficient technologies for wastewater treatment. Compared to conventional treatment systems, constructed wetlands are low cost, are easily operated and maintained. Constructed wetlands are particularly sensitive to Nonp oint source pollution(NPSP) because they function as pollutant sinks. The objectives of this study were to review the necessary contents of survey and design factors for constructing constructed wetlands and develop a modified DSS-WQMRA model for design of constructed wetlands. From the results of the case studies, in order to attain BOD target water quality, 0.27%(SF), 0.66%(FWS) wetland area of the total basin is needed.

• 대한환경공학회지
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• 제28권12호
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• pp.1287-1292
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• 2006

인공습지는 다양한 유형의 하수, 폐수에 대해 높은 제거효율을 가진 것으로 알려져 있다. 상향류식 인공습지는 10여년 전부터 많이 이용되는 이공습지 공법중의 하나이다. 본 연구에서는 인공습지의 하나인 부들(cattail)을 perlite에 식재한 상향류식 수초여과지(upflow vegetated filter UVF)장치와 수리동역학적 입자물질 전처리장치(hydrodynamic separator, HDS)를 조합한 장치를 제작하여 온실에 설치하였고, 인공하수에 대한 영양염류제거능을 분석하였다. 본 연구의 목적은 (i) 파일겆 규모의 UVF장치의 영양염류 처리능을 분석함에 있으며 (ii) Froude 수에 의한 확대설계시 직경에 대한 처리용량을 도출함에 있다 인공하수의 처리능을 분석한 결과 평균 수면적부하율 $22.7{\pm}9.6\;m^3/m^2/day$ 범위의 운전조건에서 인공하수의 처리능을 분석한 결과 평균 제거효율은 $COD_{Mn}$, TN, TP에 대해 각각 57.5%, 40.0%. 41.5%를 나타내었다. Froude수를 이용한 무차원 상사법칙을 이용하여 UVF장치의 실규모 설계용량을 산정한 결과 UVF의 직경을 3 m로 설계할 경우 75 $m^3/day$ 범위까지 처리가 가능한 것으로 산정되었다.

• 한국습지학회지
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• 제20권4호
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• pp.338-344
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• 2018

본 연구에서는 기후변화에 따른 극한 강우의 비정상성을 반영하기 위하여 GEV 분포의 3개 매개변수 중 위치매개변수를 공변량으로 적용하여, 지표면 기온(Surface air temperature, SAT) 및 이슬점 온도(Dew point temperature, DPT)을 고려한 비정상성 빈도해석이 실시된다. 부산 지점이 연구대상지점으로 선정되었으며, 5월부터 10월까지의 월 최대 일강수량을 이용하여 분석을 수행하였다. GEV 분포의 위치 매개변수를 위한 가장 적절한 공변량(기온과 이슬점 온도) 함수를 선택하기 위하여 다양한 모델을 구성하였으며, 구성된 모델 중 AIC(Akaike Information Criterion)가 가장 작은 모델을 최적 모델로 선정하였다. 분석 결과, exp(DPT)가 공변량인 비정상성 GEV 분포가 가장 적합한 것으로 나타났다. 선택된 모델을 이용하여 기후변화 시나리오에 따른 확률강우량의 영향을 분석하였으며, 부산지점의 경우 미래 이슬점 온도가 증가함에 따라 확률강우량이 증가할 가능성이 매우 높음을 살펴볼 수 있었다.

• Environmental Engineering Research
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• 제19권3호
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• pp.185-195
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• 2014

Despite the enormous technical and economic efforts to improve environmental conditions, currently about 40% of the global population (or 2 billion people) are still lack access to safe water supply and adequate sanitation facilities. Pollution problems and transmission of water- related diseases will continue to proliferate. The rapid population growth and industrialization will lead to a reduction of arable land, thus exacerbating the food shortage problems and threatening environmental sustainability. Natural systems in this context are a transdisciplinary approach which employs the activities of microbes, soil and/or plants in waste stabilisation and resource recovery without the aid of mechanical or energy-intensive equipments. Examples of these natural systems are: waste stabilisation ponds, aquatic weed ponds, constructed wetlands and land treatment processes. Although they require relatively large land areas, the natural systems could achieve a high degree of waste stabilisation and at the same time, yield potentials for waste recycling through the production of algal protein, fish, crops, and plant biomass. Because of the complex interactions occurring in the natural systems, the existing design procedures are based mainly on empirical or field experience approaches. An integrated kinetic model encompassing the activities of both suspended and biofilm bacteria and some important engineering parameters has been developed which could predict the organic matter degradation in the natural systems satisfactorily.