• 한국토양비료학회지
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• 제45권1호
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• pp.107-111
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• 2012

Eight marine sediments from Busan port in Korea were annually analyzed to examine the concentration distribution of dioxins from 2006 to 2010. Yearly mean concentration of dioxins ranged from 186.3 to $383.3pg\;g^{-1}$ in real values and 5.087 to 8.541 pg-TEQ (Toxicity equivalency) based on dry weight of samples. The dioxin concentration at the site near fishing market was the highest concentration among all sampling sites. Also the dioxin concentration at the sites with various pollutant sources such as large ships, sewage influx and thermal power station as well as fishing market was higher than that of the sites without specific pollutant sources. Another main factor that affects the dioxin concentration is topography characteristics of the bay. The bay has relatively high dioxin concentration because of the lack of the pollutant diffusion. This study demonstrated that the dioxin concentration in the site with pollutant sources and the lack of the pollutant diffusion was relatively high as compared with the other sites. As a result of contribution ratio of dioxin congeners, OCDD (Octachlorodibenzodioxin) in all sites was major contributor in real value, in contrast, dioxin congeners in TEQ values were dominated by 2,3,4,7,8-PeCDF.

• Water Engineering Research
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• 제3권2호
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• pp.135-142
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• 2002

This study investigates the effects of sediment on the flow characteristics such as velocity distribution, friction velocity, turbulent intensities, Reynolds stress, etc. Particle tracking velocimetry (PTY) is used to measure the vertical flow field. Results show that flow over the high bed-load concentration region has larger values of mean velocity and friction velocity and smaller values of turbulence intensities, compared to those for flow over the low bed-load concentration region.

• 물과 미래
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• 제29권2호
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• pp.129-141
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• 1996

일점연속 채취, 멱 속도 분포 및 Laursen의 토사농도 분포식을 이용한 총 부유 유사량 계산방법을 제안하였다. 이 방법은 미국 리오그안데 강에서 채취한 자료에 의해 검증되었다. 이 방법으로 계산된 농도분포는 $\beta$, $\kappa$, 그리고 w의 보편적인 값을 사용하여 계산한 보정 전수심 채취방법과 잘 일치하였다. 지역특성에 맞는 농도와 속도 분포식의 계수 x 와 z를 사용하였을 때는 더 좋은 결과를 얻을 수 있었다. 일점 채취에 사용한 이 방법과 일반적으로 많이 쓰는 전수심 채취를 사용한 방법과의 총 유사량의 차이는 채취때 생길 수 있는 오류 정도로 작은 것이었다. 일점 연속 채취에 의한 총 부유 유사량 측정은 여러 가지 중요한 이점을 가지고 있다. 채취 시간에 및 비용을 절감할 수 있으며 채취를 자주 할 수 있고 유사량 변화에 신속하게 대응할 수 명실상부 또한 이 방법은 미래에 추구해야 할 자동채취 방법으로 사용될 수 있다.

• 분석과학
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• 제16권3호
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• pp.232-239
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• 2003

청주시 석남천 유역의 4개 지점, 미호천 유역의 1개 지점, 석남천과 미호천 합류지역의 1개 지점 등 6개 지점을 기준지점으로 택하고, 각 지점의 상층, 중층, 하층에서 침전물을 채취하여 조사용 시료를 제작하였다. 한국원자력연구소의 연구용 원자로(HANARO)의 중성자 선을 이용한 중성자 방사화 분석법으로 원소함량을 분석하였다. 미국 표준연구원(NIST)의 인증표준물질을 이용하여 시료 중의 30 개 원소들의 함량을 비교법으로 분석하였다. 그 분석 결과로부터 하천오염원지역에서 하류로 이어지는 지역의 침전물 오염도분포조사 및 예측시 오염물질의 원소비중과 유속을 고려해야 하며 하천침전물의 함량분석을 위한 시료를 채취할 때 시료의 지역적 대표성을 확립하기 위해서는 원소의 비중과 유속 등을 고려하여 수직적 범위를 정할 필요가 있음을 알았다.

• 한국수자원학회논문집
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• 제37권1호
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• pp.43-54
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• 2004

본 연구의 목적은 호우시에 저수지로 유입되는 토사유출량을 산정하고 저수지내 부유사 농도의 변화특성을 분석하여 저수지의 정량적 관리를 위한 자료를 제안하기 위한 것이다. 연구는 탐진댐에 적용되었으며 강우유출관계는 Huff의 강우분포와 Clark의 유역추적법을 사용하였으며, 저수지 추적은 Puls방법을 이용하였다. 토사유출량의 산정은 범양토양손실공식을 분포형 개념을 이용 단일호우에 대해 적용하여, 적정 빈도에 대해서도 적용가능하도록 하였다. 또한, 저수지내에서의 부유사 농도는 2차원 수리모형인 RMA-4를 이용하였다. 연구 수행결과 호우발생시 저수지에서의 취수가능기간에 대한 계산이 가능하며, 이를 이용하여 재현기간 및 강우량에 따른 여러 측면에서 용수공급에 따른 일정 수질 유지를 위한 자료를 제시하였다. 이는 강우시 저수지 수질관리를 위한 기초자료로 사용 가능하다.

• International Journal of Fluid Machinery and Systems
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• 제10권2호
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• pp.146-153
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• 2017

Sediment flow through hydropower components causes hydro-abrasive erosion resulting in loss of efficiency, interruptions in power production and downtime for repair/maintenance. Online instruments are required to measure/capture the variations in sediment parameters along with collecting samples manually to analyse in laboratory for verification. In this paper, various sediment parameters viz. size, concentration (TSS), shape and mineral composition relevant to hydro-abrasive erosion were measured and discussed with respect to a hydropower plant in Himalayan region, India. A multi-frequency acoustic instrument was installed at a desilting chamber to continuously monitor particle size distribution (PSD) and TSS entering the turbine during 27 May to 6 August 2015. The sediment parameters viz. TSS, size distribution, mineral composition and shape entering the turbine were also measured and analysed, using manual samples collected twice daily from hydropower plant, in laboratory with instruments based on laser diffraction, dynamic digital image processing, gravimetric method, conductivity, scanning electron microscope, X-ray diffraction and turbidity. The acoustic instrument was able to capture the variation in TSS; however, significant deviations were found between measured mean sediment sizes compared to values found in the laboratory. A good relation was found for turbidity ($R^2=0.86$) and laser diffraction ($R^2=0.93$) with TSS, which indicated that turbidimeter and laser diffraction instrument can be used for continuous monitoring of TSS at the plant. Total sediment load passed through penstock during study period was estimated to be 15,500 ton. This study shall be useful for researchers and hydropower managers in measuring/monitoring sediment for hydro-abrasive erosion study in hydropower plants.

• 한국환경보건학회지
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• 제27권4호
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• pp.25-34
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• 2001

Heavy metal level and distribution in sediment and bivalves from the tidal flats along the mid-western coast, Korea. were investigated in this study. The averages of heavy metal concentrations in sediments from 5 sampling sites ranged from 86.35-187.77mg/kg for Mn. 13.25-17.73mg/kg for Zn.6.80-11.85mg/kg for Cr,4.28-6.25mg/kg for Ni, 1.85-3.09mg/kg for Cu, 0.004-0.02()mg/kg for Cd and 5.70-10.41 mg/kg for Pb, respectively. From the results of heavy metal concentrations in mussels, the levels of Mn and Fe concentrations in S. strictus collected from S1 antral S2 sites were particularly high. Deviations of heavy metal concentrations am(Ing the individual mussels from the same site could be largely minimized by selecting mussel samples of the limited range in body size(8.5-11cm). Among the mussels of the limited body size, heavy metal concentrations both in the flesh and in the whole soft part were not strongly related to the body size. It was shown that ,in S. strictus, Cu moves fast into the flesh parts after absorption, while Pb and Fe move fast into the non-flesh parts. Overally. the heavy metal concentration in the tends to increase with that in the whole soft parts. The concentration factors(heavy metal concentration in 5. strictus/heavy metal concentration in sediment) showed that, of the examined meta1s. Cd is the most cumulative in the body of S. strictus followed by Zn and Cu, while Mn, Cr. Ni and Pb are not cumulative.

• Water Engineering Research
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• 제2권1호
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• pp.49-61
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• 2001

A grid-based KIneMatic wave soil-water EROsion and deposition Model(KIMEROM) that predicts temporal variation and spatial distribution of sediment transport in a watershed was developed. This model uses ASCII-formatted map data supported from the regular gridded map of GRASS (U.S. Army CERL, 1993)-GIS(Geographic Information Systems), and generates the distributed results by ASCII-formatted map data. For hydrologic process, the kinematic wave equation and Darcy equation were used to simulated surface and subsurface flow, respectively (Kim, 1998; Kim et al., 1998). For soil erosion process, the physically-based soil erosion concept by Rose and Hairsine (1988) was used to simulate soil-water erosion and deposition. The model adopts single overland flowpath algorithm and simulates surface and subsurface water depth, and sediment concentration at each grid element for a given time increment. The model was tested to a 162.3 $\textrm{km}^2$ watershed located in the tideland reclaimed ares of South Korea. After the hydrologic calibration for two storm events in 1999, the results of sediment transport were presented for the same storm events. The results of temporal variation and spatial distribution of overland flow and sediment areas are shown using GRASS.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2001년도 학술발표회 논문집(I)
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• pp.25-34
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• 2001

A grid-based KIneMatic wave soil-water EROsion and deposition Model (KIMEROM) that predicts temporal variation and spatial distribution of sediment transport in a watershed was developed. This model uses ASCII-formatted map data supported from the regular gridded map of GRASS (U.S. Army CERL, 1993)-GIS (Geographic Information Systems), and generates the distributed results by ASCIIl-formatted map data. For hydrologic process, the kinematic wave equation and Darcy equation were used to simulate surface and subsurface flow, respectively (Kim, 1798; Kim et al., 1993). For soil erosion process, the physically-based soil erosion concept by Rose and Hairsine (1988) was used to simulate soil-water erosion and deposition. The model adopts sing1e overland flowpath algorithm and simulates surface and subsurface water depth, and sediment concentration at each grid element (or a given time increment. The model was tested to a 162.3 km$^2$ watershed located in the tideland reclaimed area of South Korea. After the hydrologic calibration for two storm events in 1999, the results of sediment transport were presented for the same storm events. The results of temporal variation and spatial distribution of overland flow and sediment areas are shown using GRASS.

• 한국환경과학회지
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• 제13권9호
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• pp.819-826
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• 2004

In order to elucidate the polycyclic aromatic hydrocarbon concentration and its origin in arctic area, four arctic brown algae (Laminaria saccharina, L. digita, Alaria esculenta, Desmarestia aculeata), one marine invertebrate (Echinoidea) and sediments were collected from Kongsfjorden in Spitsbergen from the late July to early August, 2003. In case of macroalgae, the young blade part above growth point and the old stipes and blades beneath growth point were separated and analyzed for polycyclic aromatic hydrocarbons (PAHs) in an attempt to check the mechanism of uptake in macroalgae to accumulate PAH. There was no difference in PAH concentrations between sampling sites (Stations B and C), species, and blades beneath and above growth point. PAH concentrations in all samples collected in this study were relatively higher than those reported in other areas of arctic. Especially, station C, which is known as an unpolluted area, showed 10 times higher PAH concentration (8,765 ng/g) in sediment than station A (694 ng/g) around harbor. In addition high PAH concentration, station C had very higher proportion of methylated PAH to parent PAH in sediment than station A. Source analysis using PAH isomer pair ratios as indicators showed that Kongsfjorden area seemed to be relatively contaminated with PAH derived from direct petroleum input.