• 대한환경공학회지
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• 제32권2호
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• pp.175-184
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• 2010

본 연구에서는 유역모형인 BASINS/HSPF와 연계하여 비점유달부하량을 유황별(갈수기, 저수기, 평수기 등)로 산정하는 방법을 개발하고, 이를 전남지역에 위치한 동복천 유역에 적용하여 그 효용성을 평가하였다. 동복천 유역에 대한 BASINS/HSPF 모형의 보정 검증결과는 유출유량, BOD 및 T-P의 신뢰도지수가 각각 1.59, 1.41, 1.28로서 실측값과 예측값의 유사성은 높게 나타났다. 이와 같이 구축된 BASINS/HSPF 모형을 사용하여 동복천 유역의 갈수기, 저수기, 평수기에 대한 BOD와 T-P 비점유달부하량을 각각 구하면, 연간 일평균 비점배출부하량과 대비하여 0.36과 1.09, 0.82와 2.19, 6.02와 16.90이였다. 이러한 결과는 비점유달부하량을 유황별로 산정하여 서로 다르게 반영할 필요성이 있음을 보여주고 있으며, 이러한 경우에 본 연구에서 개발한 유황별 비점오염유달부하량 산정방법은 유용하게 사용될 수 있을 것이다.

• 환경영향평가
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• 제18권5호
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• pp.271-280
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• 2009

The objective of this study is to develop a reliable flow forecasting model based on neural network algorithm in order to provide flow rate at stream sections without flow measurement in Nakdong river. Stream flow rate measured at 8-days interval by Nakdong river environment research center, daily upper dam discharge and precipitation data connecting upstream stage gauge were used in this development. Back propagation neural network and multi-layer with hidden layer that exists between input and output layer are used in model learning and constructing, respectively. Model calibration and verification is conducted based on observed data from 3 station in Nakdong river.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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• pp.252-252
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• 2003

• Membrane and Water Treatment
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• 제11권2호
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• pp.87-95
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• 2020

The worldwide shortage of water resources is a major environmental issue. Using pure water for drinking and domestic purposes is a bigger issue than other environmental issues. Industrialization and Urbanization have even polluted rainwater. In China, when it rains, rainwater is stored on the roof or other sources of storage for daily use resulting in pollution. Several studies have been conducted to treat rainwater. The objective of this study is to evaluate the efficiency of constructed wetlands by using ACF as a medium. So, this study aims to treat rainwater in Wuhan city through a Composite Vertical Flow Constructed Wetlands. First, rainwater was stored in the tank while it flows out of the roof, further it is processed in constructed wetlands. The constructed wetlands is consisted with plants Calamus and Chives, adding ACF (prepared from luffa) has achieved great results in this study. Results show that the pollutants have been removed to a considerable level, there were significant differences in removal rates under different HRT at 6h, 9h and 12h respectively. Therefore, Composite Vertical Flow Constructed Wetlands is recommended for total nitrogen and Ammonia nitrogen and total phosphorus.

• 환경영향평가
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• 제22권4호
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• pp.319-327
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• 2013

This study was conducted to identify runoff characteristics of pollutants using flow duration curve(FDC) and load duration curve(LDC) in Youngbon A watershed during 2009~2011. A flow rate and pollutant load in the study watershed were estimated by equation of stage-discharge and discharge-loads rating curve. From these methods, BOD, T-N, and T-P have evaluated whether water quality standards would have attained. Results showed that BOD loads of about 50% plotted above the LDC, while T-N and T-P loads of about 50% plotted below the curve. It means that BOD of about 50% have exceeded the water quality criteria, while T-N and T-P of about 50% have complied with the water quality standards. Meanwhile, BOD, TN and T-P loads plotted above the LDC of low flows, implying that they were more affected by point pollution sources than nonpoint pollution sources in the study watershed.

• 한국환경과학회지
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• 제17권7호
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• pp.743-753
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• 2008

Gwangyang Bay is often severely confronted by photochemical pollutants due to its location and dense emissions. It is located in a basin on the south coast of the Korean peninsula and is crossed by a remarkable cluster of hills and mountains of a small horizontal scale that forms a channel. Clearly, the air flow field has a great influence on the dispersion of air pollutants. The characteristics of the wind flow patterns have an important effect on the dispersion of pollutants emitted. In these situations, the distribution of the ozone concentration is extremely complicated because of the superposition of circulations of the air flow fields, especially in complex coastal region. In this study, we examined the distribution of the high level ozone on Gwangyang Bay particularly during the episode day (for 5 years). Among these days, A high level ozone was induced by the development of a sea/land breeze local circulation system, as well as by an anabatic/catabatic flow from the mountains and valley with weakening of the synoptic wind. High level ozone distribution pattern(6 types) on Gwangyang bay is analyzed and the comparison of each pattern reveals substantial localized differences in intensity and distribution of ozone concentration from the site coherence and UPA analysis of ozone concentration. The observed VOC concentration had much difference in concentrations and daily variations between Jungdong and Samil.

• 한국물환경학회지
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• 제35권6호
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• pp.497-509
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• 2019

After the Total Maximum Daily Loads(TMDLs) was applied, it became beyond the limit of concentration management. However, it does not adequately reflect the characteristics of various watersheds, and causes problems with local governments because of the standard flow set. Thus, in this study, the Han River system is organized into four groups in estimating the Pollution Contribution by applying the Flow Duration Curve(FDC) created by the daily flow of data from the HSPF. And the method of this study is expected to be valuable as basic data for the TMDLs. As a result, Group I contains the main watersheds with no large hydraulic structures and tributary watersheds. There is no specificity in the FDC and the Pollution Contribution is estimated as rainfall runoff. Group II contains watersheds near the city where the FDC is maintained above a certain level during the Low Flow Conditions and the Pollution Contribution is estimated as the discharge flow of large scale point pollution facilities. Group III contains the main watersheds in which the large hydraulic structures are installed and FDC is curved in the Low Flow Conditions. So the Pollution Contribution is estimated as the water quality of the large hydraulic structures. Group IV contains the upstream in mainstream watersheds in which the large hydraulic structures are installed and the FDC is disabled before the Low Flow Conditions. As the flow is concentrated in the High Flow Conditions, the non-point pollution sources are estimated as the Pollution Contribution.

• 한국환경과학회지
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• 제22권2호
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• pp.225-234
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• 2013

The relationship between debris flow and topographical factors is essential for the reliable estimation of soil loss. The objective of this paper is to estimate stability index and soil loss for assessing landsliding risk caused by debris flow. SIMAP and RUSLE are used to estimate stability index and soil loss, respectively. The landsliding risk area estimated by using SIMAP is found to be different from the large land area estimated by RUSLE. It is found that the spatial distribution of soil cover significantly influences landsliding risk area. Results also indicate that stability index and soil loss, estimated by soil cover factor, improve the assessment of landsliding risk.

• 한국가구학회지
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• 제18권4호
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• pp.307-311
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• 2007

An experiment was conducted to know the essential oil penetration depth in radial and longitudinal direction of Prunus sargentii. Oil penetration depth was found greater than radial flow depth. Vessel conducted oil more than wood fiber. In radial direction, body ray parenchyma was found more permeable than marginal ray parenchyma and it was about 138% times higher. Furthermore penetration depth of oil in intercellular space was greater than ray parenchyma and it was about 250% higher than ray parenchymas. Initial flow speed was found high and then it gradually decreased.

• 한국환경과학회지
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• 제26권1호
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• pp.11-21
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• 2017

In this study, bacterial growth was assessed by flow cytometry analysis of fluorescent probes-stained bacteria. Flow cytometry has many advantages of rapid analytical time, a low standard deviation, and highly sensitive detection of live and Dead E.coli over colony forming assay. When untreated bacteria were stained by using Thiazole Orange (TO) and Propidium Iodide (PI), double staining had a short analytical time as compared with that of single staining while its error rate was similar to that of single staining. Through double staining experiments, it was determined that optimal concentrations for TO and PI staining were 420 nM and $9.6{\mu}M$, respectively.