• Korean Chemical Engineering Research
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• 제55권4호
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• pp.478-482
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• 2017

고분자 전해질 연료전지의 구동과정 중 습도제어는 매우 중요한 제어 조건이다. 물 관리 측면에서는 저가습 조건이 유리하고, 배출수 활용 및 에너지 효율면에서는 고가습이 유리하다. 본 연구에서는 배출수 활용면에서 저가습과 고가습 구동 과정에서 배출수의 특성에 대해서 연구하였다. 배출수의 불순물은 막과 전극의 열화 과정에서 발생하는 것이므로 저가습과 고가습 조건에서 막전극합체(MEA)열화에 대해서도 연구하였다. 연료극 0% RH의 저가습 조건에서 라디칼 발생속도가 커 고분자 막 열화의 주요 원인임을 보였다. 양쪽 극 모두 고가습(RH 100%) 0.6 V에서 불소 이온 농도 약 20 ppb로 낮은 농도를 나타내서, 수전해 원료수로 사용하기에 충분하였다. 고가습 조건에서 배출한 응축수에서 0.2 ppb 이하의 매우 낮은 농도의 백금이 검출되었다.

• 한국물환경학회지
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• 제34권6호
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• pp.678-687
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• 2018

The purpose of this study was to understand the unique and complicated feature of urban stream receiving various inflows. The Yangjae stream, the second tier of the Han River, runs through the southern parts of Seoul, Korea and its middle part flows on the boundary of Seoul where land use is actively changing. Stream flow was greatly influenced by rainfall. Other than rainfall events, effluent discharge from wastewater treatment plant (WWTP) comprised 51 % of stream flux. As a result, majority ions water chemistry was changed at the receiving zone of the discharged effluent (Zone A). Its contribution increased to 69.9 % at the second sampling period with low stream flow. In the middle zone, inflows from the northern area, recently developed to a residential district showed low $NO_3-N$ and high $HCO_3$, Ca, $SO_4$, and $SiO_2$ indicating the effects of groundwater and concrete. One inflow (T-8), with extremely high Na and Cl, median $SiO_2$, was assessed to have anthropogenic influence, however its contribution to main stream was under 1 %. Road construction near Y-13 also affected water chemistry leading to the highest Na and Cl concentration. These hydro chemical changes can be critically used to evaluate the changes in water budget and fate of chemicals in a peri-urban watershed occasioned by human activities on the Yangjae.

• 한국환경기술학회지
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• 제19권6호
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• pp.586-599
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• 2018

산업단지의 배출시설관리와 배수로 수질오염물질의 배출 특성을 파악하기 위하여 하남산업단지와 첨단과학산업단지의 배출업체 16개 업체와 산업단지 배수로 4개를 포함한 11개 지점을 선정하여 조사하였다. 그 결과 배출업체 16개 업체 중 12개(75 %)의 업체에서 폐수배출시설 설치 허가 및 신고 시 등록한 항목이외의 특정수질유해물질이 검출되었고, 기타오염물질은 16개 업체 중 11개(약 69 %)의 업체에서 허가 및 신고 항목과 다른 오염항목이 검출된 것으로 조사되었다. 그리고 Formaldehyde, Mn, Zn, Ba 항목이 16개 업체 중 11개 업체에서 배출되는 것으로 나타났다. 특히, 특정수질유해물질 중 Cu는 0.029 ~ 0.929 mg/L로 모든 배출시설에서 검출 되는 것으로 나타났고, 영산강수계 주요 산단 배수로 및 본류에서도 As, Dichloromethane, Chloroform 등이 검출되었으나, 제한적인 범위(1종 ~ 3종)에서 수행되어 배출업체에서 배출되었다고 개연성을 평가하는 것은 한계가 있기 때문에 보다 많은 연구가 필요할 것으로 보인다. 향후 배출업체의 범위를 확대 조사하여 수질오염물질 DB를 구축하고, 허가 및 신고사항을 배출물질에 맞게 개선하는 것이 필요하다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.555-559
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• 2001

A by-product, waste sludge water produced from ready mixed concrete(remicon) factories may affect our environmental contamination if it is discharged without proper waste disposal. In Korea, all waste sludge water has been recycled in the way of mixing water of remicon, but the quality of the concrete then produced can be deteriorated, so it might cause slump loss or irregular compressive strength. In this study, waste sludge water is divided into two parts, remicon sludge and residual water in order to make it's property more stable. Then, the remicon sludge and high-alkaline residual water were used as admixture and alkali activator respectively. In this paper we research about quality of with remicon sludge and residual water and performed the fundamental properties of cement matrix mixed with remicon sludge and residual water.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 추계학술대회논문집
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• pp.95-107
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• 2000

The primary purpose of dredging work is to maintain navigational readiness and to increase environmental amenity, so that the dredging project which is composed of excavating, removing, transporting, storing and disposing dredged material must be carefully managed to insure that dredging works are completed in a cost-effective and environmentally safe manner. The most important point in dumping operations is an estimating and reducing the impacts of discharges at the dumping area. One of the most effective method for the reduction of ecological impacts at dumping area is using the schematic process composed of the sophisticated plan, precise work and predicting/reducing the impacts based on the numerical model and field observation. In this study, the numerical model is used to predict the near-field spatial fate and begavior of effluent discharged from Confined Dumping Facility(CDF) located near coastal area. To to this purpose, reappearing of tidal current was preceded. The model is then applied to Mokpo harbor, where capital dredging and maintenance dredging are conducted simultaneously and the CDF is under construction;. In the series of model case study, we found that the near-field behavior of effluent discharged from CDF was governed by the receiving water condition, outfall geometry, characteristics of efflent and CDF operating conditions.

• Environmental Analysis Health and Toxicology
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• 제19권4호
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• pp.375-382
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• 2004

This study was designed to investigate potential endocrine disrupting effects of several industrial wastewater effluents discharged from cosmetic, plaiting, paint, textile industry using EROD bioassay and E-Screen assay. The results of E-screen assay showed that textile industrial wastewater could act as a full agonist and cosmetics and plaiting industrial wastewater could act as a partial agonist. On the contrary, the wastewater discharged from paint industry did not show any estrogenic effect. Estrogenic activity in the effluents of cosmetic and paint industrial wastewater was lower than that in the influents indicating that the wastewater treatment process minimized the effects of discharges on water quality. Despite of these results, it was recognized that wastewater treatment was not always minimize toxic impact. In this study, increased estrogenic effect was observed in the effluents of plating and textile wastewater, and EROD activity was increased in the effluents of cosmetic and plating wastewater.

• 한국항만학회지
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• 제14권4호
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• pp.429-439
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• 2000

The primary purpose of dredging work is to maintain navigational readiness and to increase environmental amenity. Therefore the dredging project, which is composed of excavating, removing, transporting and storing or dumping dredged material, must be carefully managed to insure that dredging works are completed in a cost-effective and environmentally safe method. The most important point in dumping operations is evaluating and decreasing the impacts of dumping works at the dumping area. One of the most effective method for this purpose is using the schematic process composed of the sophisticate plan, precise work and predicting/reducing the impacts based on an numerical model being closely linked with field observation. In this study, a numerical model is used to predict the spatial transport and fate of the effluent discharged from the confined dumping facility(CDF) located at a coastal area. To achive this purpose, numerical models were used for reappearing the tidal current of concerned area. These models were then applied to Mokpo harbpr where capital dredging and maintenance dredging are being conducted simultaneously and the CDF is under construction. In series of model case study, we found that the effluent discharged from CDF was governed by the receiving water condition and outfall geometry, so that limit of near-field was 14∼500 meter down stream and 4∼150 meter in transverse direction. dilution ranged from 1.1 to 8.2 on the cases. Long-term diffusion characteristics was governed by the dilution rate during near-field behavior, ambient conditions and CDF operation modes.

• 한국습지학회지
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• 제16권4호
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• pp.413-422
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• 2014

국내의 수질정책은 하천으로 방류되는 방류수의 농도를 규제하는 방식에서 총량을 규제하는 방식으로 바뀌었다. 또한 수질오염총량관리제가 실시되어 각 수계의 구역별로 목표 수질이 정해지게 되었다. 수질오염총량관리제가 성공적으로 이행되기 위해서는 점오염원 및 비점오염원으로부터 배출되는 오염물질의 부하량을 정확하게 파악해야 한다. 이에 본 연구는 농촌의 밭지역을 대상으로 27회의 강우유출수 모니터링을 실시하였으며, 모니터링 결과를 활용하여 밭지역으로부터 배출되는 오염물질의 부하량 및 원단위 등을 산정하였다. 그 결과, 유기물질인 BOD 및 $COD_{Mn}$의 경우 오염물질의 평균 유출농도는 10.5mg/L와 19.6mg/L로 나타났으며, 영양염류인 TN과 TP는 4.5mg/L 및 2.4mg/L로 분석되었다. 한편, 국립환경과학원에서 제시한 원단위 산정 공식에 의해 산정된 원단위는 BOD $31.8kg/km^2/yr$, $COD_{Mn}$ $56.7kg/km^2/yr$, TOC $8.5kg/km^2/yr$, TSS $560.9kg/km^2/yr$, TN과 TP는 각각 $8.3kg/km^2/yr$ 및 $5.1kg/km^2/yr$로 산정되었다. 이러한 모니터링 결과는 연구자마다 그 결과 값에 차이가 있는 것으로 밝혀졌으며, 이에 정확한 원단위 산정을 위해서는 장기적인 모니터링이 이루어져야 할 것으로 판단된다.

• 환경영향평가
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• 제3권2호
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• pp.25-32
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• 1994

This study was carried out as the Anyang creek water quality management using Geographic Information System (GIS) is the purpose of this pilot project to apply a GIS to environmental management field. Analysis of water quality data has been investigated using GIS with modeling of water quality management for the Anyang creek. The results of this study are summarized as follows: 1. The concentration of Mercury in sediment was increased rapidly nearby A26(Nightsoil Treatment Plant) and maximum was showed at A18 (Imgok bridge). Cadmium was increased rapidly at A35(Chulsan bridge). 2. River water quality management using visible computer system as GIS is effective to make decision for water quality management plan and database of environmental factors should be completed before applying GIS. 3. When water pollution accident is occurred in the river water system, pollutant source can be traced and analysed systematically using GIS to manage pollutants discharged into the river water system.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.74-74
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• 2010

The aqua-plasma is the non-thermal plasma in electrical conductive electrolyte by generates the vapor film layer on the immersed metal electrode surface. This plasma can generate the hydroxyl radical by dissociate the water molecule with the plasma electron. To develop the plasma discharge device for high efficiency in the hydroxyl radical generation, proper model for estimation of plasma power is necessary. In this work, the 1-D spherical model was developed, considering temperature dependence material constants. The relation between the plasma power and hydroxyl generation was also studied by the comparison between the optical emission intensity from the hydroxyl radical using monochromator and estimated plasma power. First, the thickness of vapor layer thickness was estimated using the Navier-Stokes fluid equation in order to calculate the discharge E-field inside vapor layer. Using the E-field magnitude and power balance on the plasma generation, it was possible to estimate the plasma power. The plasma power was assumed to uniformly fill the vapor layer and the temperature of vapor layer was fixed in the boiling temperature of electrolyte, 375K. In the experiment, the aqua-plasma was discharged in the saline by applied the voltage on the bipolar electrode. The range of applied voltage was 234 to 280V-rms in the frequency of 380 kHz. Two type electrodes were produced with two ${\Phi}0.2$ tungsten. The plasma power was estimated from the V-I signal from the two high voltage probes and current probe. The estimated plasma power agreed with the profile of emission intensity when the plasma discharged between the metal electrode and vapor layer surface. However, when the plasma discharged between the metal electrodes, the increasing rate of emission intensity was lower than the increase of plasma power. It implies that the surface reaction is more sufficient rather than the volume reaction in the radical generation, due to the high density of water molecule in the liquid.