• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.197-210
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• 2012

The KOrea Multi-Purpose SATellite(KOMPSAT)-2 has a capability to provide a cross-track stereo imagery using two different orbits for generating various spatial information. However, in order to fully realize the potential of the KOMPSAT-2 stereo imagery in terms of mapping, various tests are necessary. The purpose of this study is to evaluate the possibility of mapping using the KOMPSAT-2 stereo imagery. For this, digital plotting was conducted based on the stereoscopic images. Also the Digital Elevation Model(DEM) and an ortho-image were generated using digital plotting results. An accuracy of digital plotting, DEM, and ortho-image were evaluated by comparing with the existing data. Consequently, we found that horizontal and vertical error of the modeling results based on the Rational Polynomial Coefficient(RPC) was less than 1.5 meters compared with the Global Positioning System(GPS) survey results. The maximum difference of vertical direction between the plotted results in this study and the existing digital map on the scale of 1/5,000 was more than 5 meters according as the topographical characteristics. Although there were some irregular parallax on the images, we realized that it was possible to interpret and plot at least seventy percent of the layer which was required the digital map on the scale of 1/5,000. Also an accuracy of DEM, which was generated based on the digital plotting, was compared with the existing LiDAR DEM. We found that the ortho-images, which were generated using the extracted DEM in this study, sufficiently satisfied with the requirement of the geometric accuracy for an ortho-image map on the scale of 1/5,000.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.188-201
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• 2017

Based on a total of 272 vegetation data collected by the ZM school phytosociological study method, the composition and structural characteristics of the forest vegetation in the Sogwang-ri forest genetic resource reservoir located in Uljin-gun, Gyeongsangbuk-do were compared using the table comparison method and the TWINSPAN method, And their ecological characteristics were analyzed. The types of forest vegetation were classified into 7 types, and it was divided into two major groups, 'Slope and Ridge type', which characterized by Quercus mongolica, Pinus densiflora for. erecta, Lespedeza bicolor etc. and 'valley and concave slope', which characterized by Cornus controversa, Fraxinus mandshurica, Morus bombycis, Hydrangea serrata for. acuminata etc. The hierarchy of the vegetation unit was 2 community groups, 4 communities, and 6 subcommunities. The structural characteristics such as the total percent cover, species importance value, species diversity of the constituent species per unit area($/100m^2$) of each type of forest vegetation were also identified. In order to understand the spatial distribution of forest vegetation, 1/5,000 large-scale physiognomic vegetation map was created by the uppermost dominant species. The composition and structural characteristics of Geumgang pine(P. densiflora for. erecta) forest, which is a core community of protected area by natural and anthropogenic influences, appear as a subtype of Quercus mongolica forest, which is a potential natural vegetation, Appropriate maintenance measures seemed urgently needed.

• Spatial Information Research
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• v.1 no.1
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• pp.39-53
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• 1993

A geographical information systems(GIS) was a useful aid in the assessment of urban nonpoint source pollution and the development of a pollution control strategy. The GIS was used for data integration and display, and to provide data for a nonpoint source model. An empirical nonpoint source loading model driven by land use was used to estimate pollutant loadings of priority pollutant. Pollutant loadings were estimated at fine spatial resolution and aggregated to storm sewer drainage basins(sewershedsl. Eleven sewersheds were generated from digital versions of sewer maps. The pollutant loadings of individual land use polygons, derived as the unit of analysis from street blocks, were aggregated to get total pollutant loading within each sewershed. Based on the model output, a critical sewershed was located. Pollutant loadings at major sewer junctions within the critical sewershed were estimated to develop a mi t igat ion strategy. Two approaches based on the installat ion of wet ponds were investigated -- a regional approach using one large wet pond at the major sewer outfall and a multi-site approach using a number of smaller sites for each major sewer junction. Cost analysis showed that the regional approach would be more cost effective, though it would provide less pollution control.

• Journal of Korea Water Resources Association
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• v.39 no.5 s.166
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• pp.383-394
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• 2006

This study is for the inundation damage analysis caused by levee break, and for the applicability of GIS tool to make inundation map in the Jungrang stream basin which is one of the representative urbanized area in Korea. The FLDWAV was applied to the actual flood in 1998 to calibrate the parameters, and was used under the flood conditions of 100, 200 years and PMF for the analysis of inundation caused by the levee breach. As the conditions of the levee break, the duration of break(10, 30, 60 min), the width of break(10, 20, 30m) and the location of the break are considered. We found out that the range and the volume of the inundation are strongly influenced by the location of the levee break, the break width in order. And, we compared the two processes of making the inundation map using WMS and ArcView model. The Process 1 which use only WMS has the benefit by its simplicity but there could be considerable errors in making the inundation map, while Process 2 where the ArcView model is introduced to WMS has the capability of making detailed topography map but needs more process time. This study could contribute to levee breach flood analysis and making flood map to establish the EAP(Emergency Action Plan) in the urban basin.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1360-1364
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• 2010

도시유역 물순환 해석 모형(Catchment hydrologic cycle Analysis Tool, CAT)은 기존의 개념적 매개변수 기반의 집중형 수문모형과 물리적 매개변수 기반의 분포형 수문모형의 장점을 최대한 집약하여, 도시유역 개발 전/후의 장/단기적 물순환 변화특성을 정량적으로 평가하고 물순환 개선시설의 효과적인 설계를 지원하기 위한 물순환 해석 모형이다. 이 모형은 수문학적으로 균일하게 판단되는 범위를 소유역으로 분할하여 지형학적 요인에 의한 유출 특성을 객관적으로 반영할 수 있으며, 개발 공간 단위별로 침투, 증발, 지하수 흐름 등의 모의가 가능하도록 하는 링크-노드 방식으로 개발되었다. 모형의 UI(User Interface)는 사용자가 손쉽게 모형을 적용/관리하고, 여러 시나리오를 동시에 효과적으로 모의하여 분석할 수 있도록 설계되었다. 또한, 모든 입/출력 자료를 엑셀이나 텍스트 형식과 연동되도록 하여 프로젝트별 매개변수 관리가 용이하도록 개발하였다. 특히 본 모형에서는 사용자의 목적에 맞는 다양한 물순환 개선시설(침투시설, 저류지, 습지, 빗물저장시설, 리사이클 및 외부급수 등)의 구현 및 모의가 가능하도록 개발하였다. 여기서, 물순환 개선시설이란 빗물을 흡수하고 저류할 수 있는 도시녹지시설 혹은 구조물로서 도심 내의 불투수면을 저감시키고 유출수를 줄이면서 동시에 녹지를 확보하여 효과적인 물순환 기능에 영향을 미치는 시설들이다. 이러한 물순환 개선시설은 신도시 및 지역 혁신도시 개발 등의 대규모 토지이용변화가 예상되는 개발지역에 대한 평가 및 개선 기술을 제공하여 물순환 건전화를 위한 설계에 직접적으로 활용될 수 있는 큰 장점을 지니고 있다. 먼저 침투 시설은 계획침투량을 반영하며 토양으로의 침투량과 지하수로의 이동을 모의한다. 저류시설은 하도 내에 위치한 online 저류지와 하도 외에 위치한 offline 저류지로 구분하고 저류지 수면의 증발량과 취수량을 고려하며, 방류구를 통한 방류량을 반영하였다. offline 저류지의 경우는 하도 내의 흐름의 규모에 따라서 일정량을 넘는 경우만 offline 저류지로 유입될 수 있는 양을 산정하도록 하였으며 하류 하천으로의 방류를 반영하여 홍수 후에 저류지가 비워지도록 하였다. 유역 내의 습지는 식생과 수면에서의 증발산을 반영하였다. 습지의 저류능력을 넘는 양은 월류되어 하류로 유출되며, 방류구를 통한 방류량을 반영하였다. 빗물저장시설의 경우는 초기우수와 같은 일정량 이하의 유입량과 시설용량을 초과하는 양은 방류하도록 하였고, 물 사용량을 반영하였다. 또한, 본 모형에서는 하천 내에서 취수하여 유역으로 공급할 수 있도록 리사이클 처리노드를 계획하였다. 리사이클은 용수 이용 목적에 따라 필요지역으로 공급되는 것으로 하였으며, 하천유지용수의 목적으로 취수되어 상류 혹은 하류의 임의 지역으로 공급되는 것을 포함하였다. 또한, 유역외부에 광역으로 급수되는 공급량도 반영하도록 하였다.

• Economic and Environmental Geology
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• v.50 no.3
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• pp.239-250
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• 2017

Physically based landslide susceptibility analysis has been recognized as an effective analysis method because it can consider the mechanism of landslide occurrence. The physically based analysis used the slope geometry and geotechnical properties of slope materials as input. However, when the physically based approach is adopted in regional scale area, the uncertainties were involved in the analysis procedure due to spatial variation and complex geological conditions, which causes inaccurate analysis results. Therefore, probabilistic method have been used to quantify these uncertainties. However, the uncertainties caused by lack of information are not dealt with the probabilistic analysis. Therefore, fuzzy set theory was adopted in this study because the fuzzy set theory is more effective to deal with uncertainties caused by lack of information. In addition, the vertex method and Monte Carlo simulation are coupled with the fuzzy approach. The proposed approach was used to evaluate the landslide susceptibility for a regional study area. In order to compare the analysis results of the proposed approach, Monte Carlo simulation as the probabilistic analysis and the deterministic analysis are used to analyze the landslide susceptibility for same study area. We found that Fuzzy Monte Carlo simulation showed the better prediction accuracy than the probabilistic analysis and the deterministic analysis.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.329-337
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• 2013

This study was performed to evaluate the temporal and spatial variations of the water quality at stream flowing into the Suncheon bay in Suncheon city from October 2008 to August 2009 and to estimate the pollutant sources from the streams using multivariate analysis. Water qualities from Seo stream, Dong stream, Ok stream were evaluated as I grade(very good) that compared to the Water Quality Standard. But Haeryong stream and inlet site of Suncheon Bay in BOD were evaluated as a little bad and fair. Water quality at the stream flowing into the Suncheon Bay was could be explained up to 92.8% by three factors which were included in loading of nutrients, organic matter and total coliform group by the allochthonous matters(53.7%), Topographic Factors(25.0%), seasonal variation(14.2%). The concentrations of total nitrogen and phosphorus at sewage treatment plant and organic matters at Haeryong stream were higher than that of others, respectively. From principal component analysis and factor analysis, it could be suggested that it is very important to make an effort to reduce the nutrients and organic matters from sewage treatment plant and Haeryong stream to be in good conservation of the Suncheon bay.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.33-33
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• 2018

농업이 기간산업이었던 고대사회에서 수리시설(水利施設)의 축조는 농업의 성패를 가늠하는 중요한 요소로 정치 경제 사회 전반에 걸쳐 큰 영향을 미치는 국가적인 대규모 사업이었다. 이에 따라 수리시설의 축조 시기와 배경, 축조 기술과 운영, 구조, 몽리(蒙利) 효과 및 보수(補修)와 수축(修築) 등에 대한 연구는 우리의 농경(農耕)문화사를 밝히는데 중요한 관건이 된다. 관개(灌漑) 수리시설의 축조와 정비는 수전(水田) 개발과 밀접한 연관이 있다. 제방(堤防)을 축조함으로써 주변의 수전 개발을 촉진하고, 가뭄과 홍수로부터 안전하게 전답을 유지할 수 있어 수확량을 높이게 된다. 농업생산력의 향상은 대내적 체제 정비는 물론 치열한 국가 간의 경쟁에서 우위를 점하는데 필요한 경제적 배경이 된다. 이처럼 고대수리시설은 개인과 집단 나아가 국가의 생존을 뒷받침하는 근본이었지만, 과연 우리는 그 역사성과 의미에 대해 제대로 평가를 했던 것일까? 또한, 고대수리시설의 관개 및 치수(治水) 능력은 구체적으로 어느 정도였으며 근대에 비하면 어느 정도였을까? 일부 수리시설에 대해 관개면적을 추정한 경우는 있으나, 그 예도 많지 않을뿐더러 시기적인 변천 양상을 제대로 반영하고 있지 못하는 것이 현실이다. 본 연구는 고대로부터 원형을 비교적 잘 간직하고 있는 수리시설 중 경북(慶北) 영천(永川)의 청제(菁堤)를 대상으로 고고학적 역사학적 입장에서 보다는 수문학적(水文學的) 농업수리학적(農業水利學的) 관점에서 저수량(貯水量) 및 관개(灌漑) 면적에 따른 농업생산력을 살펴보았다. 지형 및 GIS (Geographic Information System) 정보를 이용하여 저수지의 규모 및 관개 면적을 추정하였으며 수문학적 해석 모형(模型)인 CAT(Catchment hydrologic cycle Assessment Tool)(김현준 등, 2012)을 이용하여 저수량 및 관개 가능량을 분석하였다. CAT은 공간 단위별로 침투(浸透), 증발(蒸發), 지하수(地下水)흐름 등의 모의(模擬)가 가능하도록 개발된 모형이다. 특히, 농업용 저수지 및 홍수방재용(洪水防災用) 저류(貯留)시설 등의 저류량(貯留量) 및 방류(放流量)에 대한 모의가 가능하다(장철희 등, 2012). 고대수리시설의 저수량 및 관개 면적에 따른 농업생산력을 공학적 수문학적으로 해석하는 연구는 과거물 관리 및 생산력의 실태를 좀 더 자세히 파악할 수 있는 토대가 될 것이며, 역사학적 자료와의 비교 분석을 통해 우리나라 고대수리시설의 역사성 및 우수성을 찾을 수 있을 것으로 판단된다.

• Journal of Forest and Environmental Science
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• v.27 no.3
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• pp.195-203
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• 2011

Forest in the our country is in the age that needs positive operation in order to foster economical forest. Multiple operations for making valuable forest should be conducted steadily and timely from afforestation to harvesting. In order to execute these kinds of forest operations, the construction of skid trail network that can be effectively used as a pathway for forestry machine and working space is necessary. To investigate facility effect of skid trail network, we executed the location of skid trail network through centroid method by GIS for 50ha of harvesting workplace in mechanized model forest located in Hongcheon, Gangwon Province. As a result of this research, skid trail density in this area changed from 79m/ha with current method to 42m/ha with improved method. It appeared that skid trail density with improved method is nearly half of current method even though the cutting area is the same as the current cutting area. Also, skidding distance changed from 117m with current method to 57m with improved method. It appears that skidding distance with improved method is nearly half of current method even though cutting area was enlarged in adjacent tending cutting area.

• Journal of Wetlands Research
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• v.23 no.2
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• pp.154-162
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• 2021

The naturally opened Han river estuary is a place where the flows of the Han river, Imjin river, Yaesung river meet with West Sea of Korea, so the hydrodynamic mechanism(Impact-Response) structure of Han river estuary is complex. Continuous observation and measurement due to the morphological characteristics at the estuary are required to maintain the estuary environment and river management facilities. However, the Sannam wetland(the study area) is in the military operation area. Therefore, Sannam wetland has the limited access under the control from military office. In 2020, there had a natural disaster due to flooding in August and COVID-19, and it made a survey hard. The noncontact survey technique, the analysis of LANDSAT images at Sannam wetland, was applied to analyze riverbed fluctuation and morphological transformation around Sannam wetland. LANDSAT images obtained from EarthExplorer, USGS and analyzed by QGIS. The analysis was performed based on the area and the distance near Sannam wetland. As a result, an erosion was happened on the downstream of the study area, and the upstream of the study area did not have any serious sediment transport. Considering the resolution of LANDSAT images, this noncontect survey technique is applicable to manage the study area. From the analysis of LANDSAT images, it is assumed that the tidal effect is greater than the inflow from the upstream. The pattern change of tidal response causes the damage of the river facilities near the Hangang river estuary.