• Spatial Information Research
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• v.10 no.4
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• pp.533-550
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• 2002

Soil organic matter (SOM) content and other physical soil properties were extracted from a digital soil database, the Soil Survey Geographic (SSURGO) database, to map the amount of SOM and determine its relationship with topographic positions in floodplain areas along a river basin in Douglas County, Kansas. In the floodplains, results showed that slope and SOM content had a significant negative relationship. Soils near river channels were deep and nearly level, and they had the greatest SOM content in the floodplain areas. For the whole county, SOM content was influenced primarily by soil depth and percent SOM by weight. Among different slope areas, soils on mid-range slopes (10-15%) and ridgetops had the highest SOM content because they had relatively high percent SOM content by weight and very deep soils, respectively. SOM content was also significantly variable among different land cover types. Forest/woodland had significantly higher SOM content than others, followed by cropland, grassland, and urban areas.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.141-143
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• 2003

The aim of this study is to evaluate the susceptibility of landslides at Clicap area, Indonesia , using a Geographic Information System (GIS). Landslide locations were identified from field surveys. The topographic and geological map were collected and constructed into a spatial database using GIS. The factors that influence landslide occurrence, such as slope, aspect and curvature of topography, were calculated from the topographic database and lihology and fault was extracted from the geological database. Then landslide susceptibility was analyzed using the landslide-occurrence factors by likelihood methods. The results of the analysis were verified using the landslide location data. The GIS was used to analyze the vast amount of data efficiently . The results can be used to reduce associated hazards, and to plan land use and construction.

• Spatial Information Research
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• v.6 no.1
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• pp.25-33
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• 1998

The study region encompasses about 5,900$km^2$ including the topographic maps of Kimhae, Pusan, Miryang, Yangsan, Panguhjin, Tonggok, Uhnyang, Ulsan, Youngchon, Kyongju, Pulguksa, and Kampo, all at a scale of 1:50,000. The paper discusses how to have prepared the four thematic maps, landslide and unstable slope distribution map, slope classification amp, soil classification map, and lineament density map. Using all the above maps and GIS, the relative slope-stability map for the study regiun was produced at a scale of 1:100,000 ; the map can be utilized for the regional land-use planning in the study region.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.5
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• pp.435-444
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• 2012

Although the multi-scale map database should be constructed for the web map services and location-based services, much part of generation process is based on the manual editing. In this study, the map generalization methodology for automatic construction of multi-scale database from the primary data is proposed. Moreover, the generalization methodology is applied to the real map data and the prototype of multi-scale map dataset is generated. Among the generalization operators, selection/elimination, simplification and amalgamation/aggregation is applied in organized manner. The algorithm and parameters for generalization is determined experimentally considering T$\ddot{o}$pfer's radical law, minimum drawable object of map and visual aspect. The target scale level is five(1:1,000, 1:5,000, 1:25,000, 1:100,000, 1:500,000) and for the target data, new address data and digital topographic map is used.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.6_1
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• pp.493-502
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• 2013

For various geospatial information such as planimetric and topographic features, the required accuracy may be defined depending on the purpose of GIS applications. Also, the accuracy of the geospatial information have a major impact on the quality of the raw surveying data. In order to be usefully applied the precise geospatial information, the accuracy standards must be appropriately set so that the digital map as base map can be accurately made. Before computer mapping and GIS technology existed, paper maps were drawn by hand. So, the map scale was a significant contributor to the map accuracy. As such the past, the accuracy of maps is determined the scale at which the map would be drawn, but recent trends are to treat accuracy as a one of quality elements, rather than a specification for producing the map. Therefore, the purpose of this paper is to set the new korean map accuracy standards appropriate for the construction and application of the precise geospatial information on behalf of the current representation of korean digital maps.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.6
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• pp.507-514
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• 2018

TSI (TPI-Slope Index) which is the combination of TPI (Topographic Position Index) and slope was newly proposed for landslide and applied to a landslide susceptibility model. To do this, we first compared the TPIs with various scale factors and found that TPI350 was the best fit for the study area. TPI350 was combined with slope to create TSI. TSI was evaluated using logistic regression. The evaluation showed that TSI can be used as a landslide factor. Then a logistic regression model was developed to assess the landslide susceptibility by adding other topographic factors, geological factors, and forestial factors. For this, landslide-related factors that can be extracted from DEM (Digital Elevation Model), soil map, and forest type map were collected. We checked these factors and excluded those that were highly correlated with other factors or not significant. After these processes, 8 factors of TSI, elevation, slope length, slope aspect, effective soil depth, tree age, tree density, and tree type were selected to be entered into the regression analysis as independent variables. Three models through three variable selection methods of forward selection, backward elimination, and enter method were built and evaluated. Selected variables in the three models were slightly different, but in common, effective soil depth, tree density, and TSI was most significant.

• Journal of the Korean association of regional geographers
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• v.3 no.2
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• pp.19-35
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• 1997

The purpose of this study is to find out the characteristics of landform in Geoje-Do using GIS and DTED data. The characteristics of landform in Geoje-Do are as follows; First, the height-range of Geoje-Do is $0{\sim}580m$, and the average elevation of it is 124m. Volcanic and granite region is mainly appeared at high elevation-region. But, we can't find out outstanding difference of elevation, according to its geology. The second. the slope-range of Geoje-Do is $0{\sim}52$ degree, and the average slope of it is 17.6 degree. The slope of volcanic and granite area is more steeper than any other region. But the results of analysis of the geology in Geojo-Do, don't show outstanding difference of the slope. The third, the area-rate of the aspect of Geoje-Do is almost same in all direction. And the area-rate of south-west direction is the highest. According to the geology of Geoje-Do, granite is distributed the most widely, and the area of volcanic and granite occupy 60% of entire island's area. According to analysis of influence of geology with elevation, geology has little relationship with elevation. According to analysis of geology and drainage network, streams are inclined to be developed well in Alluvium area. Drainage network is well developed throughout the entire island, except southeast area. The highest order of stream is 4 in 1:25,000 topographic map. The density of stream in Geoje-Do is very high, such as 1.6. The bifurcation-ratio of stream is also higher than 4 in all order. The length-ratio of stream is ranged from 1.24 to 3.25. According to the relationship between order and elevation. order is the greater, elevation is the lower. According to the relationship between order and slope, order is the greater, slope is the gentler. In this study, we use DTED Data, and compare it with topographic map data. According to the comparison, there is a little difference between DTED data and topographic map data. Therefore, to use DTED data in landform analysis, it is required coordinate matching process. This process is very important, and take very long time. Thus, if you use DTED in landform analysis, some processes are required. DTED data can be taken very easily, but its using is not simple. Because coordinate adjust is very hard work.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.67-74
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• 2001

Now that importance of landscape planning unique to each area is emphasized, it is necessary to conduct landscape planning by taking advantage of natural environments unique to each ares, because its natural environments are regarded as one of the assets the area possesses. This study targets at Kawachinagano City, Osaka, one of the residential areas that I not only rich in natural and historical elements, but also has been rapidly growing. The purposes of this study are to evaluate change in landscape structure over time by analyzing relation between landform and pattern of expanding the built-up area at three time points of 1932, 1967, and 1994 with GIS (ARC/INFO 7.0.3, ARC/View 3.0 (ESRI)), as well as to make some suggestions for planning landscape unique to the area. Data on main ridges, sub ridges, main rivers, and other landform were read from the elevation map, and data on woodland, and parks and open spaces (having more than 3 ha area) were read from the existing land use map. The data were used to understand the natural structure of the city from topographic viewpoint. Next, the existing land use map prepared with data on the built-up area and urban axes consisting of roads and streets were overlaid on the elevation map in order to understand relation between pattern of expanding the built-up area and the natural structure.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2002.04a
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• pp.207-217
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• 2002

수치정사사진지도를 제작하기 위한 기반 자료로 스캐닝한 수치항공사진영상과 항공사진의 왜곡 보정을 위한 표정, DEM의 추출과 편집 및 편위 수정에 이르기까지 다양한 처리절차가 필요하다. 또한 영상과 벡티 자료의 중첩을 통해 생선한 영상지도의 편집과 지도제작 작업에는 다양한 미적 요소가 필요하다. 본 연구에서는 수치항공사진 영상을 이용하여, 영상에 내포하는 기하학적 변위를 3차원 모델링 결과와 수치표고모델을 이용하여 소거하고, 수치정사사진을 제작한 후에, 1/5,000 수치지도에서 필요한 레이어와 중첩시킨 수치정사사진지도를 제작하여 그 정확도를 분석하였으며, 각 처리 단계별 문제점의 분석과 개선방안을 제시하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.173-178
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• 2004

This paper presents photogrammetric processing to generate digital elevation models and deals with the accuracy potential of SPOT-5 HRG supermode imagery for DEM generation. The DEMs obtained from digital topographic maps of 1/5000 scale were used as the refernce DEM data. DEMs extracted from HRG dats were compared with digital topograpic map DEMs on severed test sections. And digital surface model(DSM), refering to above the ground like buildings, was produced about the test built-up area.