• 대한환경공학회지
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• 제35권3호
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• pp.192-199
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• 2013

도시의 하천은 주민의 생활공간의 일부로서 환경적인 지속성을 위해 자연 친환경적으로 관리함이 바람직하나 현재 홍수예방, 또는 조경공사에 가까운 하천정비만 되어 왔으며 하천의 수질보전 및 관리를 위한 지속가능한 수질관리 방안의 수립이 필요한 상황이다. 탄동천은 대전시 유성구 추목동을 기점으로 갑천으로 유입되는 지방 2급 하천이다. 상류에는 군부대, 중류는 주거단지, 하류는 국가주요 연구단지, 그리고 국가적인 규모의 문화시설이 공존하는 지역으로 소규모하천의 자연 친화적 관리에 매우 좋은 예가 될 수 있을 것으로 전망된다. 본 연구는 탄동천에 대한 수질조사를 진행하고 전면적인 진단을 해보았다. 그 결과 상류의 하수처리장 방류수와 신성교 부근의 관거유출수가 주오염원으로 발견되었다. 탄동천 수질개선을 위해서는 이러한 오염원들에 대한 관리가 필수이며 그 대책으로 하수처리장 고도처리시설 도입과 하수처리장과 신성교 부근의 하천둔치에 인공습지를 설계하여 수질개선을 제안하였으며 1차원 수질모델인 QUAL2K를 이용하여 상술한 방안에 대한 수질개선 효과를 예측해 보았다. 모의결과 특히 T-P의 경우 0.05 mg/L 이하로 개선되는 것으로 모의되어 하천의 부영양화 방지에도 뚜렷한 효과가 있을 것으로 판단된다. 개선된 탄동천 수변공간은 인근 주민들에게 쾌적한 환경을 제공할 수 있으며 성공적인 수질관리 사례는 여타 하천관리의 설계, 시공에 큰 도움이 될 것이다.

• 한국물환경학회지
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• 제24권5호
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• pp.543-549
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• 2008

Human activities and land-use practices are intensely widening the urban areas. High impervious surface areas cover much of urban landscapes and are the primary pollutant sources which can lead to water quality and habitat degradation in its watershed. As the urban areas expand, transportation land-use such as parking lots, roads, service areas, toll-gates in highways and bridges also increase. These land-uses are significant in urban pollution due to high imperviousness rate and vehicular activities. To regulate the environmental impacts and to improve the water quality of rivers and lakes, the Ministry of Environment (MOE) in Korea developed the Total Pollution Load Management System (TPLMS) program. The main objective is to lead the watershed for a low impact development. On a local scale, some urban land surfaces can be emitting more pollution than others. Consequently, in urban areas, the unit loads are commonly employed to estimate total pollutant loadings emitted from various land-uses including residential, commercial, industrial, transportation, open lands such as parks and golf courses, and other developed land like parking areas as a result of development. In this research, unit pollutant loads derived specifically from transportation land-uses (i.e. branched out from urban areas) will be provided. Monitoring was conducted over 56 storm events at nine monitoring locations during three years. Results for the unit pollutant loads of transportation land-use are determined to be $399.5kg/km^2-day$ for TSS, $12.3kg/km^2-day$ for TN and $2.46kg/km^2-day$ for TP. The values are higher than those of urban areas in Korean MOE and US highways. These results can be used by MOE to separate the pollutant unit load of transportation landuses from urban areas.

• 한국대기환경학회지
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• 제26권4호
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• pp.367-379
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• 2010

Future climate changes over the Seoul metropolitan area (SMA) were predicted by the Weather Research and Forecasting (WRF) model using future land-use data from the urban growth model (SLEUTH) and forecast fields from ECHAM5/MPI-OM1 GCM (IPCC scenario A1B). Simulations from the SLEUTH model with GIS information (slope, urban, hill-shade, etc.) derived from the water management information system (WAMIS) and the intelligent transportation systems-standard nodes link (ITS-SNL) showed that considerable increase by 17.1% in the fraction of urban areas (FUA) was found within the SMA in 2020. To identify the effects of the urban growth on the temperature and wind variations in the future, WRF simulations by considering urban growth were performed for two seasons (summer and winter) in 2020s (2018~2022) and they were compared with those in the present (2003~2007). Comparisons of model results showed that significant changes in surface temperature (2-meter) were found in an area with high urban growth. On average in model domain, positive increases of $0.31^{\circ}C$ and $0.10^{\circ}C$ were predicted during summer and winter, respectively. These were higher than contributions forced by climate changes. The changes in surface temperature, however, were very small expect for some areas. This results suggested that surface temperature in metropolitan areas like the SMA can be significantly increased only by the urban growth during several decades.

• 한국물환경학회지
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• 제29권6호
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• pp.754-761
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• 2013

Urban floods are usually caused by the lack of drainage capacity. Hence, sewer capacity expansion methodology by replacing small pipes with bigger ones is primarily applied as a flood control measure. However, this approach is often unreasonable because of the costs and time involved. Thus, the installation of underground rainwater storage tanks with the two advantages of flood control and water conservation is proposed. This study compared the effectiveness of flood control by both the sewer expansion methodology and rainwater storage tanks using the Storm Water Management Model. Three cases were simulated in this study. The first case analyzed flood reduction by the storm sewer expansion methodology. The simulation results indicate that the overflow volume from manholes was reduced by 49% with this methodology. The second case analyzed flood reduction by installation of rainwater storage tanks. The simulation results indicate that the overflow volume was reduced by 62%. However, these two cases could not prevent urban floods completely. Hence, the third case analyzed the joint application of the storm sewer expansion methodology and rainwater storage tanks. In this simulation, flooding did not occur. Consequently, the results of this study clearly show that underground rainwater storage tanks are more effective for flood control than capacity expansion of storm sewer. Furthermore, the joint application of these two flood control measures is more effective than their separate application.

• 환경영향평가
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• 제16권1호
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• pp.79-87
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• 2007

The performance of a stream water quality analysis model depends upon many factors attributed to the geological characteristics of a watershed as well as the distribution behaviors of pollutant itself on a surface of watershed. Because the model run has to import the pollution load from the watershed as a boundary condition along an interface between a stream water body and a watershed, it has been used to introduce a pollution delivery coefficient to behalf of the boundary condition of load importation. Although a nonlinear regression model (NRM) was developed to cope with the limitation of a conventional empirical way, this an up-to-date study has also a limitation that it can't be applied where the pollution load washed off (assumed at a source) is less than that delivered (observed) in a stream. The objective of this study is to identify what causes the limitation of NRM and to suggest how we can purify the process to evaluate a pollution delivery coefficient using many field observed cases. As a major result, it was found what causes the pollution load delivered to becomes bigger than that assumed at the source. In addition, the pollution load discharged to a stream water body from a specific watershed was calculated more accurately.

• 한국환경과학회지
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• 제16권5호
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• pp.649-655
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• 2007

This study was focused on estimating instream flow, and its optimal alternative for securing the required total amount of instream flow was also researched in order to restore ecosystems and riverine aesthetics of the Mugeo Stream. the first tributary of the Taewha River flowing through the center of Ulsan. In this study the hydraulic and hydrologic conditions and water quality were investigated at specific channel reaches and representative stations of the Mugeo Stream to determine a proper estimate of instream flow. And riverine functions, such as the minimum flow, water duality conservation, fish habitat, and recreation, were considered to restore the environmental functions of the stream, As a result, the total amount of $11,500m^3/day$ was set as the target instream flow for the Mugeo Stream. It was chosen as the optimal alternative for securing the total external supply of $10,000m^3/day$ which have to be transfered from the riverbed flow diverted through the Taewha Main river at upstream of Samho bridge. The water duality throughout the Mugeo Stream channels will be improved considerably to 3-4 mg/l of BOD standard if the target instream flow is supplied and sewage is intercepted by the sanitary sewage system.

• 자원ㆍ환경경제연구
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• 제10권2호
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• pp.235-257
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• 2001

As in other Asian countries, the Korean government provides direct subsidies to endeavors that are potentially harmful to the environment. The water sector is one of the main recipients of these subsidies. The total amount of estimated direct fiscal subsidies equals 2.200 trillion won; however, the comprehensive cost of the subsidies is estimated to be much greater because environmental and social costs were not considered in the initial calculation. Most of the fiscal direct subsidies in the water sector are subsidized to urban water areas. The percentage of fiscal direct subsidies in the urban water sector to the total fiscal direct subsidies is 79.68%, while the percentage of fiscal direct subsidies in the industrial water sector is only 4.92%. Since the ratio of fiscal direct subsidies in the industrial water sector is quite small, the negative impact of removing fiscal direct subsidies for the industrial sector may be trivial. If the Korean government cuts dowm the VAT or income tax rate while reducing several types of subsidies, it will be able to achieve a double dividend effect both on the economy and the environment.

• 한국환경복원기술학회지
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• 제10권6호
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• pp.1-14
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• 2007

This study was conducted to propose the plan of creating a brooklet reflecting an water-friendly space as well as its function as the habitats of wildbird in Cheongdam Neighborhood Park in Seoul. Major fields of this study include a survey of the staus, a basic plan, a master plan, a execution; a survey of this site was focused on topography, water system, trail, existing vegetation, wildbird; a detailed plan was focused on flow plan, planting plan, facility plan. Existing vegetation was classified into 5 types; Quercus mongolica-Q. acutissima forest, Robinia pseudoacacia forest, Populus${\times}$albaglandulosa forest, artificial green space, urban area. 11 species and 49 individuals of wildbirds appeared in 2004(3~4month). The plan of creating a brooklet were divided passive-zone, eco-zone, and dynamic-zone. Environment elements of each space including a mountain stream, ecological pond, marshland, ecological landscape forest, wildbird observation trail, waterway etc. The brooklet of Cheongdam Neighborhood Park is rated high as an important space for wildbird biodiversity. Accordingly, continuous monitoring of this biotope as a urban habitat is required as the environment changes.

• 상하수도학회지
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• 제30권2호
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• pp.179-185
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• 2016

In this study, the RDII predictions were compared using two methodologies, i.e., the RTK-based and regression methods. Long-term (1/1/2011~12/31/2011) monitoring data, which consists of 10-min interval streamflow and the amount of precipitation, were collected at the domestic study area (1.36 km2 located in H county), and used for the construction of the RDII prediction models. The RTK method employs super position of tri-triangles, and each triangle (called, unit hydrograph) is defined by three parameters (i.e., R, T and K) determined/optimized using Genetic Algorithm (GA). In regression method, the MovingAverage (MA) filtering was used for data processing. Accuracies of RDII predictions from these two approaches were evaluated by comparing the root mean square error (RMSE) values from each model, in which the values were calculated to 320.613 (RTK method) and 420.653 (regression method), respectively. As a results, the RTK method was found to be more suitable for RDII prediction during extreme rainfall event, than the regression method.

• Environmental Engineering Research
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• 제22권4호
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• pp.393-400
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• 2017

One of the big problems facing municipalities is the management and control of urban flooding where urban drainage systems are under growing pressure due to increases in urbanization, population and changes in the climate. Urban flooding causes environmental and infrastructure damage, especially to roads, this damage increasing maintenance costs. The aim of the present study is to develop a decision support tool to identify the performance of storm networks to address future risks associated with climate change in the Middle East region and specifically, illegal sewer connections in the storm networks of Karbala city, Iraq. The storm water management model has been used to simulate Karbala's storm drainage network using continuous hourly rainfall intensity data from 2008 to 2016. The results indicate that the system is sufficient as designed before consideration of extra sewage due to an illegal sewer connection. Due to climate changes in recent years, rainfall intensity has increased reaching 33.54 mm/h, this change led to flooding in 47% of manholes. Illegal sewage will increase flooding in the storm system at this rainfall intensity from between 39% to 52%.