• Journal of the Mineralogical Society of Korea
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• v.27 no.3
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• pp.125-134
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• 2014

The Janggun mine (Longitude $E129^{\circ}$ 03' 40", Latitude $N36^{\circ}$ 51' 19") was once operated as an underground mine and recently significant amount of mine and leachate water has been discharged from the mine adits and tailing dumps. Mine and leachate waters are characterized by neutral to weakly basic pH values (6.81-9.59). Major cations and anions have concentrations between 6.70-129.80 mg/L of Mg, 289.29-661.02 mg/L of Ca, 4.74-14.38 mg/L of Mn and 1205.00-2448.69 mg/L of $SO{_4}^{2-}$. Brownish yellow precipitates that found in the stream bottom consist of poorly crystallized 2-line ferrihydrite ($Fe_2O_3{\cdot}0.5H_2O$. Scanning electron microscope (SEM) photographs show that brownish yellow precipitates consisted of micro-sized granular particles of about $0.1{\mu}m$ in diameter. Semi-quantitative energy dispersive spectrometry (EDS) analyses show that these samples contained mainly Fe with minor Mn, Ca, Si and As.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.1
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• pp.119-131
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• 2003

Rainfall-runoff process is under the control of hydrologic parameters having temporal and spatial variety. Accordingly, it is difficult to efficiently deal them since many parameters and various information are required to perform hydrologic simulation. So the purposes of this study is to estimate the runoff volume by frequency using GIS techniques and NRCS method. The analysis of frequency rainfall is analyzed using FARD 2002 program and the result of goodness of fit test show that Log-pearson type III is suitable distribute type for the applied area. TOPAZ program used for the analysis of DEM data examining into geological characteristic. NRCS curve numbers estimated using landuse map and soil map for the estimation of effective rain fall in the basin. The storm Type II and Type III were used as the type for the application of NRCS. The result of application show that the runoff volumes above 80 years frequency in return period have similar patterns regardless of Type II and Type III. In addition, the results of comparison with runoff volumes by frequency in the report of river improvement master plan show that it have similar volumes as the relative errors for them of 80, 100 years frequency are each 7.65%, 5.33%.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.506-525
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• 2007

Incision into bedrock channel is the primary control of landform evolution, but research into bedrock incision process stagnated for long time. Due to the scaling problem of the application of results from flume studies to bedrock channel, there is a strong need to simulate the bedrock incision process with more realistic models. As a part of investigation into controls of bedrock channel incision, three-dimensional changes of rock surface with abrasion was investigated with physical modelling. 18 rock plates were abraded with various sediment particle size and sediment load and abraded surfaces of the plates were scanned with high resolution 3-D scanner. To identify the spatial pattern of erosion of the rock plates, various methods were used. There was no synthetic or holistic method that showed all features of bedrock plate produced by abrasion, so each plate was analyzed using some available methods. Contour maps, shaded relief maps and profiles show that abrasion concentrated on the centre of plate (cross profile) and upstream and downstream edges (longitudinal profile) and eroded area extended inwards. It also found that the cracks and boundaries of forming materials easily eroded than other parts. Changing patterns of surface roughness were investigated with profiles, regression analysis and spectral analysis. Majority of plates showed decrease in small-scale roughness, but it depends on microstructures of the plates rather than general hardness or other factors. SEM inspection results supported this idea.

• KSBB Journal
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• v.14 no.6
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• pp.718-723
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• 1999

In order to treat of alkaline dye-processing wastewater, alkalophilic strains biodegrading azo dye, Acid red 1, is isolated from natural system, and optimal culture conditions are examined using response surface analysis, statistical analysis system program. 15 different species which grow in alkaline culture media are isolated from the effluent and river soil discharged from wastewater treatment plant in dye industrial complex. One strain which has the best decolorization efficiency is chosen, and named as AR-1. The result of the examination of carbon, nitrogen and phosphorus sources which have influence on growth and decolorization reveals that optimum carbon, nitrogen and phosphorus sources are 1.0% fructose, 1.0% polypeptone, 1.0% yeast extract and 0.5% $K_2HPO_4$, respectively. In order to optimize of biodegradation conditions of dye by response surface analysis, the characteristics of decolorization and cell growth according to culture temperature and time are monitered. The result shows that the one is optimum 34.77$^{\circ}C$ for 12.97 hours; the other at 34.73$^{\circ}C$ for 12.96 hours. While, optimal conditions of culture that satisfy both cell growth and decolorization are the temperatures from 32.86$^{\circ}C$ to 36.36$^{\circ}C$ and the period of 10.96 to 15.75 hours, respectively.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1997.10a
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• pp.65-66
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• 1997

우리나라의 대부분 하천과 인공댐의 경우 조류발생에 기여하는 영양염은 질소, 인 그리고 규소 등인데 특히 인이 생산제한 인자로 작용하고 있다. 따라서 인을 적절히 제거할 경우에는 조류 발생에 의한 수질의 악화와 수이용의 저해요인을 배제할 수 있어 이에 대한 연구가 많이 진행되어 왔다. 지금까지와 연구는 인의 화학적 응집 침전법, 생물학적 처리법에 대하여 수행되어 왔으나 설비자금, 운영비, 운전기술, 슬러지 생성 그리고 제거효율 등에서 만족스런 결과가 도출되지 못하여 현장 적용을 하지 못하고 있는 실정이다. 이러한 현실을 감안하여 우리의 자연 환경에서 쉽게 자할 수 있는 황토를 모재로하여 Al3-과 Fe3-, Ca2-을 적절히 배합하여, 주로 인을 선택적으로 제거하 고자 개발된 황토의 흡착능력 그리고 흡착 메카니즘에 대한 기본적인 연구를 하고자 (1) 등온흡착실험을 통하여 흡착용량을 평가하고 (2) 흡착제거속도를 평 가하였고 (3)파과시간 및 흡착특성을 파악하기 위해 column 흡착실험을 하였다 또한 (4) 황토내의 Al3-, Fe3-과 Ca2- 등이 인의 화학적 흡착에 기여하는 정도를 파악하여 흡착메카니즘을 규명하고자 하였다. 먼저 흡착용량실험을 위하여 PO3-4-P 농도 3ppm의 용액 200mf에 황토 0.2g, 0.5g, 1.0g, 2.0g을 각각 투여한 후 충분한 흡착평형이 일어나게 24시간 동 안 130rpm으로 $25^{\circ}C$ 등온반웅조에서 저어주어 흡착평형에 도달하면 상등액을 GF/C Filter로 여과한 후, 여액에 대해 PO3-4-P의 농도를 Ascrobic he건법으로 측정한 결파, Freundlich 등온흡착식에 의하면 K값은 17.34와 16.28이었으며 1/n 값은 1.32와 1.42로 인흡착 성능이 뛰어난 것으로 평가되었다. 둘째, 흡착속도 실험은 PO3-4-P 농도 1.5ppm의 용액 2f에 259의 황토를 투여하고 충분한 혼합이 일어날 수 있도록 170rpm으로 교반하면서 시간별 용액 의 농도 변화를 측정한 결과, 0.45mg/g/m교의 속도로 15분만에 94.3%의 인 제거 효율을 보였다. 셋째, 직경 12mm의 glass column에 황토를 209 채우고 1.5ppm의 PO34P 용액을 2.Sne11in의 유량으로 통수 시킨 후, 시간에 따른 농도 변화를 측정한 결과, 원수 농도의 50%에 해당하는 파과점까지 약 70시간 만에 도달하였다. 넷째, Al3-, Fe3-과 Ca2- 등이 화학적 흡착에 기여하는 정도를 파악하기 위 하여 황토 2g에 대하여 Hieltijes and Lijklema 방법에 의해 Adsorbed-p, Nonapatite inorganic-P(NAI-P), Apatite-p, Organic-P로 구분하여 분석하고, 총인(Total Phosphorus)을 Standard Methods에 따라 Persulfate digestion후 0.45 m membrane 여지 여과하여 여액에 대해 PO3-4-P의 농도를 Ascorbic Acid 법으로 측정한 결과, NAI-P가 가장 큰 비율을 차지하였고, 부원료로 첨가된 금속 양이온 중 Fe3-이온이 흡착에 기여하는 정도가 가장 큰 것으로 평가되었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.4
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• pp.23-32
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• 1988

The rates of infiltration contributed to the flow fo water in an unconfined aquifer under the partially penetrated stream at an ungaged station and the corresponding base flow in channel are coupled by using the hydraulic and/or hydrologic characteristics obtained from the geomorphologic and soil maps. For the determination of groundwater flow, the linearized model which is originally Boussinesq's nonlinear equation is applied in this study. Also, a stream flow routing model for base flow in channel is based on a simplification of the Saint-venant. The distributed runoff model with piecewise spatial uniformity is presented for obtaining its solution based on a finite difference technique of the kinematic wave equations. The method developed in this study was tested to the Bocheong watershed(area : $475.5km^2$) of the natural stream basin which is one of tributaries in Geum River basin in Korea. As a result, it is suggested that the rationality of hydro-graph separation according to a wide variability in hydrogeologic properties be worked out as developing the physically based subsurface model. The results of the present model are shown to be possible to simulate a base flow due to an arbitrary rate of infiltration for ungaged basins.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.506-513
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• 2014

As a measure to overcome the limit of small city which is weak in spontaneous competitiveness and to improve the quality of environmental, cultural and economic life of dwellers, it analyzed the geographical characteristics of city, movement path, economic status and other simple problems comprehensively and produced the vague problem solutions for dwellers and the practical direction for design using the 3D simulation rendering in order to suggest the result to change the potential for urban policy into substantial alternative. Geochang-gun selected as research area is evaluated for the place with high symbolic value of bridge in terms of environment, and the new design development for this kind of public design can be the good measure to increase the competitiveness of the city. This research is to understand the direction of the bridge recreation project which provides the cultural space connecting with other areas and improves the competitiveness of small city and to suggest the appropriate bridge design in order to provide the reasonable maintenance direction related to the future development of public design and the achievement of the symbolism of the region and to suggest the examples of public design for the urban competitiveness. For this purpose, focusing on Wicheon-stream in Geochang County, Gyeongsangnam-do selected as the research and development area for bridge design, it is to design the concept design bridge newly emphasizing the symbolism of bridge-oriented city for the development of future city.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.3
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• pp.13-21
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• 1987

The object of this study was to evaluate the management alternatives with respect to the attainable water quality and total cost(construction+O & M cost) in order to devise a reasonable water quality management system. Joong Ryang-cheon stream located Seoul, Korea was taken as the study area, and dissolved oxygen concentration as the water quality index. Water quality simulation model QUAL2E and linear programming optimization technique were used for scientific and rational analyses. It was assumed that the improvement of water quality could be obtained by the treatment of major point sources where imaginary treatment plants were constructed. And by this, the relationship between total cost of the treatment plants and the stepwise improvement of water quality was studied. The result showed that 3.5mg/l of DO(=dissolved oxygen) level at best could be attained in Joong Ryang-cheon stream during summer. When the DO standard was set 3.0mg/l in the severely polluted regions, more than 5.0mg/l of DO level can be achieved by the construction of 4 treatment plants. Also, the cost comparisons showed that the uniform treatment method is economically inefficient(\$24.8{\times}10^8$) in comparison with the least cost method(\$22.9{\times}10^8$), and there is little difference between the least cost method and the the zoned treatment method(\$23.0{\times}10^8$) that is regarded as more equitable, which shows the characteristics of this basin.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.2
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• pp.138-150
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• 1997

The late Quaternary stratigraphy of the tidal deposits in the Hampyung Bay, southwestern coast of Korea comprises 1) Unit III (nonmarine fluvial coarse-grained sediments), 2) Unit II (late Pleistocene tidal deposits), and 3) Unit I (late Holocene fine-grained tidal deposits) in ascending order. The basements of the Hampyung Bay is composed of granitic rocks and basic dyke rocks. These three units are of unconformally bounded sedimentary sequences. The sequence boundary between Unit I and Unit II, in particular, seems to be significant suggesting erosional surface and exposed to the air under the cold climate during the LGM. The uppermost stratigraphic sequence (Unit I) is a common tidal deposit formed under the transgression to highstand sea-level during the middle to late Holocene.

• Korean Journal of Ecology and Environment
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• v.38 no.3 s.113
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• pp.412-419
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• 2005

The dynamics of zooplankton community and its relationship with environments were studied at the middle stretch (Waekwan, RK; river kilometer; above 175 km from the estuary dam) of large regulated river, Nakdong River from 1998 to 2002. There were distinct inter-annual variations and seasonal changes in total zooplankton abundance in the study site (ANOVA, p<0.01), displaying similar pattern in three years from 1999 to 2001 except 1998 and 2002. The annual average rotifers abundance during the study period was 43${\pm}76 ind. $L^{-1}$ (mean${\pm}$s.d., n = 118), followed by adult copepodids (1.6${\pm}$4.8 ind. $L^{-1}$), and small cladocerans (0.4${\pm}$1.2 ind. $L^{-1}$). Among the rotifers, Brachionus spp. Polyarthra spp., Colurella spp., Keratella spp.·, and Trichocerca spp. were the most common taxa. These species occupied more than 80% of the total rotifer abundance throughout the study period. Total zooplankton abundance rapidly increased in spring and fall and remained low throughout the winter. During summer, zooplankton dynamics seemed to be largely affected by hydrological parameters. Overall, rather the external factors (hydrological factors of the river) than internal factors (food condition for zooplankton such as phytoplankton biomass) appear to be responsible for changes in zooplankton dynamics in the middle stretch of the river.