• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.295-301
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• 2004

Satellite captures images periodically and economically over the area wider than aerial photographs, and reconnaissance to unapproachable area. For these advantages, mapping using high resolution satellite image has high potentials of marketability and development. Therefore, utilization of satellite image in mapping and GIS is expected to be growing and research on describable feature, positional accuracy and, possible mapping scale is urgently needed. This research presented that Quick Bird orthoimage could be used to update digital map on a scale of 1:5,000. Quick Bird image was corrected geometrically based on ground control points. DEM was generated using height data of digital topographic map. The orthoimge was produced by digital differential rectification based on DEM which was generated using height data of digital topographic map(scale 1;5,000 and 1;1,000). When the digital topographic map was overlaid with the orthoimage, it was very easy to find changed region or new features builded after the map compiled.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.1
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• pp.37-44
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• 2003

This study is focused on development of generalization processing for 1/25,000 digital mapping using l/5,000 digital map. The generalization processing for digital map included in spatial and attribute information consists of 3 steps. The first, elimination of layer which is not included in 1/25,000 feature code. The second, classification of 8 feature codes. The third, merging of spatial and attribute information. Therefore using generalization workflow developed in this project, automatic generalization system will develope optimal in the future and also contribute product to small scale digital map and thematic map.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.2
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• pp.199-208
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• 2001

The digital map in Korea has been producted and utilized independently according to scales such as 1:1,000, 1:5,000, and 1:25,000. Therefore, whenever we need to obtain the spatial data of other scales, we have to product the digital maps over and over again which it is time-consuming and ineconomic. To solve these problems, it has been accomplished many researches on map generalization to make digital maps in small scale from the master data of large scale. This paper aims to analyze the conversion characteristics of the large scale to the small scale by simplification of map generalization. For this purpose, it is proposed the algorithm for the simplification process of digital map and it is investigated the simplification characteristic of digital map through the experiment on the conversion of 1:5,000 scale into 1:25.000 scale. The results show that Area-Preservation algorithm indicates the good agreement with the original data in terms of the area and features of building layer compared to Douglas-Peucker algorithm and Reumann-Witkam algorithm.

• Spatial Information Research
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• v.6 no.2
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• pp.201-216
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• 1998

The :Ministry of Transportation and Construction has a plan to finish up the construction of digital topographic map which is based. on airphoto intepretation method by the end of 1998 as a part of NQS (National Geogaphic Information System) Project. The digital topographic map, especially 1:1,000 scale, is used as a basemap of many local government's GIS projects. The digital topographic map, however, does not include property information such as cadastral and urbanplan data that are essential for the GIS database of many local governments. This study aims to develop a set of technical guidelines for the construction of digital cadastral map, which can be used together with the 1:1,000 scale digital topographic map, through 1) analysis of the inconsistency between topographic map and cadastral map, 2) comparison of technical methods for the integration of GIS data that have different accuracy, and 3) requirement analysis of the departments related to urban planning of Seoul Metropolitan Govemment. For this research, edited digital cadastral map has been experimentally produced in pilot study area, a part of Hwanghak-dong, Shindang-dong, and Soongin-dong in Seoul.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.3
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• pp.229-238
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• 2013

Development of methodologies to generate the small scale map from the large scale map using map generalization has huge importance in management of the digital topographic map, such as producing and updating maps. In this study, the selection methodology of map generalization for the road network data in digital topographic map is investigated and evaluated. The existing maps with 1:5,000 and 1:25,000 scales are compared and the criteria for selection of the road network data, which are the number of objects and the relative importance of road network, are analyzed by using the T$\ddot{o}$pfer's radical law and Logit model. The selection model derived from the analysis result is applied to the test data, and the road network data of 1:18,000 and 1:72,000 scales from the digital topographic map of 1:5,000 scale are generated. The generalized results showed that the road objects with relatively high importance are selected appropriately according to the target scale levels after the qualitative and quantitative evaluations.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.381-386
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• 2006

Currently, 1/5,000 Digital Topographic Map covers the whole country with administrative boundary of Gu, while some region has already been constructed with 1/1,000 digital topographic map has legal boundary of Dong. Here, Dong in 1/1,000 scale represents the legal boundary which is used in the address most of time. Therefore, there is no administrative-Dong yet although it is very useful in various fields. In this study, we suggested a method to construct the administrative boundary extending to the level of Dong empirically. In addition, the practical application of the administrative boundary in GIS is discussed. Two methods are applied to construct the administrative boundary to the level of administration-Dong; using the edited cadastral map and the digital topographic map. When the edited cadastral map is used, some problems such as boundary discordance to superordinate administrative area is appeared. On the other hand, using digital topographic map showed simple construction processes and easy connection with other framework data. Therefore, it is recommended that the digital topographic map should be used in the construction of the administrative boundary It would be useful as framework data in various industries and public operations.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.4 s.22
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• pp.95-103
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• 2002

The accuracy of Digital Map does not meet the user's expectation, including the many errors caused while producing the project, this will be useless resulting waste of enormous national budget. To solve this Accuracy problem, clear regulations about the position accuracy of scaled Digital Map should be set immediately and provide the users with accurate information about Digital Map enabling the users to use Digital Map for each GIS application field. For this reason, the position accuracy evaluation of existing Digital Maps produced in diverse methods is on demand. In this study, therefore, we performed horizontal position survey of local selected Facilities Total Station equipment to evaluate the horizontal position accuracy of 1:1,000, 1:5,000 scaled Digital Map, obtained standard deviation using the results, performed T-Test to confirm the presence of bias and evaluated the position accuracy of Digital Map.

• Spatial Information Research
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• v.6 no.2
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• pp.233-245
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• 1998

This study focused on developing a comprehensive strategy to revise 1:1,000 digital topographic maps for Seoul metropolitan area in terms of both organizational and technical aspects. First of all, we analyze the elements of' the revision strategy in the organization domain and produce four alternatives. Of these alternatives, we suggest a best alternative which appears to be practically sound. Secondly, we review four possible map updating methodologies, paper map digitization, a partial topographic map revision method, a method utilizing scanned aerial photographs, and a method using digital orthophotos. Through a detailed technical analysis and cost analysis of each method, we suggest a reasonable map updating method. Finally, we provide a guideline for distributing 1:1,000 digital topographic maps based on the digital map distribution policy National Geography Institute.

• Korean Journal of Remote Sensing
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• v.34 no.6_3
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• pp.1329-1350
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• 2018

There have been many applications to observe Earth using synthetic aperture radar (SAR) since it could acquire Earth observation data without reference to weathers or local times. However researches about digital map generation using SAR have hardly been performed due to complex raw data processing. In this study, we suggested feasibility of producing digital map using SAR stereo images. We collected two sets, which include an ascending and a descending orbit acquisitions respectively, of KOMPSAT-5 stereo dataset. In order to suggest the feasibility of digital map generation from SAR stereo images, we performed 1) rational polynomial coefficient transformation from radar geometry, 2) digital resititution using KOMPSAT-5 stereo images, and 3) validation using digital-map-derived reference points and check points. As the results of two models, root mean squared errors of XY and Z direction were less than 1m for each model. We discussed that KOMPSAT-5 stereo image could generated 1:25,000 digital map which meets a standard of the digital map. The proposed results would contribute to generate and update digital maps for inaccessible areas and wherever weather conditions are unstable such as North Korea or Polar region.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.3
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• pp.215-228
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• 2003

National Geography Institute(NGI, National mapping agency) has been producing national basemap in automated process since middle of 1980's toward the systematic and efficient management of national land. In 1995, Korean government initiated a full-scale implementation of the National Geographic Information System(NGIS) Development Plan. Under the NGIS Development Plan, NGI began to produce digital maps in the scales of 1:1,000, 1:5,000, 1:25,000. However, digital maps of 1:250,000 scale, which are currently used for national land planning, were not included in NCIS Development Plan. Also, the existing laws and specifications related to digital maps of 1:250,000 scale are not clearly defined. It is fully appreciated that data dictionary will be a key element for users and generators of digital maps to rectify the existing problems in digital maps as well as to maximize the application of digital maps. There(ore this study proposed a feature classification system, which defines features that should be represented in digital map of 1:250,000 scale, and data dictionary as well.