• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.4
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• pp.136-145
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• 2009

Site characteristic is an important input parameter in the geologic hazard assessments including, but not limited to, earthquakes, liquefaction and landslides. Although it is a routine to use data collected by boreholes or seismic prospecting for site classifications, we used indirect methods using the geologic and the topographic maps. A site classification map in the Gyeongsang Province has been produced by GIS tools based on geologic age, rock types, and elevations from the geologic map and the topographic map of Korea. Site B (rock site) is dominant in the study area, although softer soils are observed along rivers and in reclaimed lands. We have found that 73% of the site classification results in the study are in concordance with those obtained from borehole data. Observed discrepancies are attributed to errors in the geologic and the topographic maps. For some sites, the origin of the differences is not clear, which requires a further field study or a drilling. Site classification from this study provides essential information for reliable hazard assessments of earthquakes, floods, landslides and liquefaction. Results obtained in the study also play a crucial role in land use planning for developing areas.

• Magazine of the Korean Society of Agricultural Engineers
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• v.23 no.1
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• pp.64-74
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• 1981

The stream morphological characteristics of watershed have important influence upon the analysis of runoff. In this study, the effect of the map scale on the stream morphological characteristics was used on the data taken from 15'(1:50, 000) and 7'30"(1 :25,000) topographic maps which could cover the whole Miho River basin This basin are the first tributary of the Geum. River. Otherwise, the longitudinal stream bed profile was calculated by Yang's theoretical stream bed profile, equilibrium profile and actual profile. In the result of this investigation the conclusion is that the resultant relationship obtained from different topographic maps in the scale on the same stream system has come upon the same result as the stream morphological characteristics. Therefore, the great amount of time and effort can be saved in studing the stream morphological charecteristics by using the 15' instead of the 7'30"map system excluding the first order streams.

• Journal of the Korean association of regional geographers
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• v.13 no.5
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• pp.563-575
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• 2007

This study aims to investigate a possibility of using topographic information by web mapping in open environments. Web mapping intends to focus on a map analysis and application of the function and geo-visualization. Functions of Web topographic info-map include a spatial analysis, enlargement and minimization, movement, landuse information, user-controling 3 dimension map, landform cross-section analysis, shortest path analysis. The web system adopts SVG(scalable vector graphics), MYSQL, PHP, XML for mapping. SVG has open source policy, so everyone can use it, as well, it is effective on flexible database linkage, cartographic representation. 3D map is intended to represent 3D map by user-controlled sunshine putting pixel opacity by elevation values after making DEM. Landform is designed to show a cross-section analysis and statistics by retrieving height information from database engine with clicking two points on the map. Shortest path analysis within regions uses Dijkstra's algorithm. Near future, resultantly, the area of WebGIS will have to meet more social demands for use-created geo-information and application, so more researches are needed to be web mapping more applicable for users.

• Spatial Information Research
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• v.12 no.1
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• pp.43-56
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• 2004

Basically a land parcel consists of a land parcel number, land category, land boundary and area, and land value is mostly determined by the land category. Generally people want to change their land use to increase their land value so that they can expect more benefits from the land. However, changing land use causes several problems with land properties, haphazard urban expansions and land category non-coincidences. Unfortunately, no effective solutions exist for land category non-coincidence problems. In this study, we proposed a methodology that can classify the land category based land covers using high resolution satellite images and digital topographic maps. For this, we obtained a parcel based land use/cover classification map. Using both this classification map and a digital cadastral map, we inspected land category non-coincidences. As a result, land category non-coincidence rates could be statistically measured and interpreted and demonstrate a possibility that we could quantitatively interpretate and measure cadastral non-coincidence automatically.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.4
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• pp.373-383
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• 2001

This study conducted pilot mapping project to know the possibility of mapping with medium resolution satellite imageries. For this purpose, mapping experiments were conducted with each stereo model imageries of SPOT, KOMPSAT, and IRS- lC. And positional accuracy, analysis of detectable and describable features, and comparison with existing digital map were checked, possible mapping scale and cost analysis were conducted with these results. Regarding SPOT imagery, digital photogrammetric workstation was used for stereoplotting. Regarding KOMPSAT and IRS-lC imageries, because there were data format support problems. head-up digitizing was performed with ortho imageries rectified with DEMs generated by image matching. The results of experiments show that such features as wide road, river, coast line, etc are possible to detect and depict but many other features are not for SPOT, KOMPSAT, and IRS-lC imageries. On the aspect of mapping, therefore, SPOT is available for 1/50,000 topographic map revision, KOMPSAT and IRS-lC for 1/25.000 topographic map revision.

• Journal of The Geomorphological Association of Korea
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• v.27 no.2
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• pp.1-17
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• 2020

This study evaluated a debris landform distribution potential area map in the southwest region of the Korean peninsula. A GIS spatial integration technique and logistic regression method were used to produce a distribution potential area map. Seven topographic and environmental factors were considered for analysis and 28 different data set were combined and used to get most effective results. Moreover, in an accuracy assessment, the extracted results of the Distribution Potential area were evaluated by conducting a cross-validation module. Block stream showed the highest accuracy in the combination No. 6, and that DEM (digital elevation model) and TWI (topographic wetness index) have relatively high influences on the production of the Block stream Distribution Potential area map. Talus showed the highest accuracy in the combination No. 13. We also found that slope, TWI and geology have relatively high influences on the production of the Talus Distribution Potential area map. In addition, fieldwork confirmed the accuracy of the input data that were used in this study, and the slope and geology were also similar. It was also determined that these input data were relatively accurate. In the case of angularity, the block stream was composed of sub-rounded and sub-angular systems and Talus showed differences according to the terrain formation. Although the results of the rebound strain measurement using a Schmidt's hammer did not shown any difference in topographic conditions, it is determined that the rebound strain results reflected the underlying geological setting.

• Journal of the Korean GEO-environmental Society
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• v.17 no.9
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• pp.21-28
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• 2016

The purpose of this study is to compare the three areas that each estimated by using three different river topographic maps. For construction of river topographic maps, the data used in this study are ASTER, SRTM and a 1:5,000 scale digital map data sets in 14 streams of the Cheongdo-gun and Uiseong-gun. HEC-GeoRAS, RAS Mapper, and RiverCAD model are applied for the flooding area analysis using observed data and design rainfalls. The result of analysis is to compare observed flooding area based on the flood plain maps with estimated inundation area by hydraulic models and constructed river topographic maps. The results of this study are as follows; Flooding area by HEC-GeoRAS model is similar to the inundation area of flood plain map and appears in order of RAS Mapper, and RiverCAD model in all watersheds. Flood inundation area by SRTM DEM is similar to the result of 1:5,000 scale digital map in all watersheds and all analysis models. The SRTM DEM shows the most similarity to the digital map than ASTER DEM in all of the watershed scale and analysis models. HEC-GeoRAS and RiverCAD model are efficient models for flood inundation analysis in small watershed and HEC-GeoRAS and Ras Mapper model are efficient in medium to large watershed.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.3
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• pp.70-78
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• 2004

The aerial photographic mission is a difficult work because aircraft must be flown along the specified flight lines, not marked on the ground. This study has been carried out for the development of aerial photographic guidance system, which enables us to make aerial photographic task easier. Such a flight guidance system is able to display a variety of map informations in a quick and efficient way in order to guide pilot. For this purpose, we first developed the nationwide aerial navigation map database that provides the topographic map information used for topographic interpretation and aeronautical chart information used for the flight security. Next, we developed the aerial photographic guidance system which uses the aerial navigation map as base map. It is concluded that the developed system can display the various map informations quickly and do any other photographing guidance tasks well in fast moving airplane.

• Journal of the Korean Geographical Society
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• v.41 no.4 s.115
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• pp.375-390
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• 2006

The Carte do Cassini is the first accurate topographic map of an entire country and it influenced enormously in the development of cartography in other countries. The purpose of this paper is to examine the production process and characteristics of the Carte do Cassini, and to and the place of 'Carte de Cassini' in the development of cartography. For this, firstly, the background of French national topographic mapping is examined and scientific work of the Cassini family is resumed. Second, the map production process is considered; location and attribute data collection, copperplate printing, social and economic difficulties. Third, map characteristics such as map projection, sheet numbering system, positional accuracy, legend, typographies, and depiction of cartographic signs are explored. Finally, the influence of the Carte de Cassini on cartographic development and its historical meaning is discussed.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.65-70
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• 2003

The weight-of-evidence model one of the Bayesian probability model was applied to the task of evaluating landslide susceptibility using GIS. Using the location of the landslides and spatial database such as topography, soil, forest, geology, land use and lineament, the weight-of-evidence model was applied to calculate each factor's rating at Boun area in Korea where suffered substantial landslide damage fellowing heavy rain in 1998, The factors are slope, aspect and curvature from the topographic database, soil texture, soil material, soil drainage, soil effective thickness, and topographic type from the soil database, forest type, timber diameter, timber age and forest density from the forest map, lithology from the geological database, land use from Landsat TM satellite image and lineament from IRS satellite image. Tests of conditional independence were performed for the selection of the factors, allowing the 43 combinations of factors to be analyzed. For the analysis, the contrast value, W$\^$＋/and W$\^$-/, as each factor's rating, were overlaid to map laudslide susceptibility. The results of the analysis were validated using the observed landslide locations, and among the combinations, the combination of slope, curvature, topographic, timber diameter, geology and lineament show the best results. The results can be used for hazard prevention and planning land use and construction