• Spatial Information Research
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• v.10 no.3
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• pp.455-468
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• 2002

Toward the systematic and efficient management of national land, National Geography Institute(NGI, National mapping agency) has been producing national basemap in automated process since middle of 1980's. Under the National Geographic Information System(NGIS) Development Plan, NGI began to produce digital maps in the scales of 1:1,000, 1:5,000, 1:25,000 since 1995. However, those of digital maps that have been generated under NGIS Development Plan need to be modified and corrected due to lack of technology and experience in making digital maps. In this context, those digital maps generated are currently in great need for improving the data dictionary. It is fully appreciated in previous research that data dictionary will be a key element far users and generators of digital maps to rectify the existing problems in digital maps as well as to maximize the application of digital maps. In this paper, we analyzed existing problems in digital maps based on previous researches and interviews with engineers in different fields of geospatial engineering. And then, the existing data dictionary has been redefined and modified. In the line of modification process, a relational matrix was established fur each topographic feature defined in the existing feature classification system. This paper presents newly proposed data dictionary which conforms to newly defined feature classification system from previous research performed by NGI.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.8 no.1
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• pp.31-40
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• 1990

In this study, sample area was selected to compare the conventional method with photogrammetic method in basic planning of country club. Also various elements of planning, such as vegetation and water system, were considered through interpretation of aerial photographs and topographic maps, vegetation maps and water system maps were made as well as digital terrain models. These were used to analyse tophographic changes and landscape. As a result of comparing with the conventional method, it was shown that photographic interpretation could give more detail values than the conventional method, and that the digital terrain model could predict changes of topography, landscape and water system with more asccuracy. Consequently, the method of digital terrain model and photographic interpretation proved to be more effective than the conventional method in the case of water treatment, and planning of landscape and land utility.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.307-313
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• 2004

정부에서는 사회 경제적으로 많은 문제를 발생시키고 있는 지적불부합지 문제를 해결하고자 지적재조사 사업을 계획하였으나 수 조원에 달할것으로 예상되는 막대한 사업비와 국민적인 이해부족으로 인하여 중단이 되었다. 이렇게 지적재조사 사업이 전면 중단된 상황에서 지적불부합을 효율적으로 해결하기 위해서는 현지 측량 방식에 기반하여 불부합지를 조사하고 정리하기보다는 현재 구축되어 있는 지적도 전산화 데이터와 GIS 관련 데이터 등을 최대한 활용하여 조사할 수 있는 새로운 방법론의 모색이 필요하다. 본 연구에서는 기 구축되어 있는 수치지적도와 수치지형도를 이용하여 지적불부합을 측정할 수 있는 방법론과 절차를 개발하였다. 그리고 모든 과정을 상용 GIS 소프트웨어를 이용하여 구현하였다. 방법론의 실험을 위해 실제 사례지역을 선정하여 적용하여본 결과 불부합을 정량적으로 조사하고 해석할 수 있는 가능성을 제시할 수 있었다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.4
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• pp.383-392
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• 2003

In this study, we investigated 3 methods for precise registration of buildings into LIS. They are : 1. using digital topographic maps, 2. using registered building maps, 3. cadastral surveyings on sites. The first method was found that it hardly met required precision, and the second one was also lack of precision because of unmatched actual buildings with registered ones and many unregistered buildings. The last method produced the most precise results, although it required laborious cadastral surveyings on sites. Considering the importance of building registration as it shows the ownerships of properties, the third method was thou인t to be desirable.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.239-243
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• 2004

Recently various thematic maps and image maps using aerial photograph and satellite imagery are frequently made. The geo-referencing is essential to make image map and topographic map using aerial photograph and satellite imagery. For this geo-referencing, Ground Control Points (GCPs) are needed. In this paper, we used GPS relative positioning to measure GCP ground coordinate and the accuracy of 8cm level was achieved. We made GCP image chips for the efficiency of geo-referencing and carried out the bundle adjustment of aerial photographs using GCP image chips to acquire the GCP photo coordinate with image matching technique. Finally we analyzed the accuracy of bundle adjustment compared to the accuracy of the case in using digital maps to acquire GCP photo coordinate.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.272-275
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• 2005

The digital map expresses natural topographies and artificial things with 3D position coordinates in the computer such as the road, railway, building, river, mountain, paddy and dryland. Therefore, the digital map is regarded as an important factor in the information-oriented society. However, it is difficult to maintain the most recent topographic information all the times because of restricted budget and time. For that, the efficient method corresponded with the digital map should be presented. This study aims to suggest the way to make an estimate of updating cost for 1:5,000 scale digital map by using remotely sensed data. To predict updating area of the digital map, the screen digitizing method was applied to the overlapped images and digital maps.

• Journal of Korean Society for Geospatial Information Science
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• v.7 no.2 s.14
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• pp.81-91
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• 1999

The study on the updating of the database of Geo-Spatial Information System that is necessary condition to GSIS operation have executed actively. In this study, digital orthophotos were produced by using the product of digital photogrammetry process and then multiscale digital orthophoto maps were generated tv the concept of image pyramids. The produced digital orthophoto has 2.092 meters accuracy compared to 1:5,000 topographic map. This digital orthophoto can be implemented in various Geo-Spatial Information System, providing valuable spatial reference for other objects in the database.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.22 no.3
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• pp.277-284
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• 2004

The subject of this study is to apply experimentally In resolution stereo imagery of IKONOS to producing 1:50,000 scale maps for Munsan area in Paju, being near the Military Demarcation Line, is inaccessible for aerial photography. Ground control points were acquired from GPS surveying to perform geometric corrections on images. Digital maps were produced from IKONOS stereo imagery on the digital photographic workstation. From field investigation, RMS errors of the plane and vertical positions are estimated respectively at $\pm$1.706m and $\pm$1.231m, respectively. These plane and vertical accuracies are within the tolerance limits of those provided in the NGIS Digital Topographic Map Production Rules. Therefore this suggested method is recommended for producing the large scale digital maps of 'No flight' zone near the M.D.L.

• Spatial Information Research
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• v.16 no.3
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• pp.317-330
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• 2008

In this paper, the acquisition of digital imagery and the orthoimage generation were performed to set up working process. And another purpose of this thesis is to evaluate the accuracy of orthoimage by overlapping digital topographic map and digital cadastral map on it. The digital topographic map and digital cadastral map were superimposed on the orthoimage to check the accuracy as another approach of evaluation. The RMSE is ${\pm}0.364m$ in X direction and ${\pm}0.413m$ in Y direction with digital topographical maps(1/5,000). And the RMSE is ${\pm}1.283m$ in X direction and ${\pm}1.085m$ in Y direction with digital cadastral map. It is necessary for the application of a newly developed digital aerial camera to make an exact synchronization between GPS/IMU data and image data, use a technology for setting a standard image resolution and the number of ground control points.

• Journal of the Korean Association of Geographic Information Studies
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• v.2 no.3
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• pp.23-34
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• 1999

This study proposed the possibility of GIS to analyze stream physiographic characteristics of river basin which is important control factor in complex water management. Based on five 1:25,000 topographic maps which cover Yengchon Dam area locates upper area of Kumho River, this study analyzed the characteristics using Arc/Info(UNIX) GIS. Comparing its results and those from the existing method using digital planimeter, it could conclude as follows; First, as the results of the analysis of hypsometric curve of Yeungchon Dam area, it has the topographic characteristics of youth and maturity. And the landform of Yengchon Dam area has developed with regularity when Horton's three laws on the morphology of stream is applied. Second, the possibility of applying GIS to data management and utilization is sufficient even if it requires long time to construct topographic attribute data. Finally, a further research is needed on watershed direction with landform for the purpose of analyzing water source management and topographic property effectively.