• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.3
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• pp.331-340
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• 2005

Digital map is very important digital geographic information which is the base for various fields such as building and using the geographic information system (GIS), planing the regional development, and etc. Therefore, it needs high accuracy. Then we offer the advanced technique which minimizes errors on digital maps, using the automated inspection through the whole figures. In addition this new technique raises the economical efficiency as well as accuracy applying the automated error detection method which can recognize, search and classify errors automatically.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.1 s.39
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• pp.67-73
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• 2007

Recently, three-dimensional (3D) GI (Geospatial Information) using LiDAR system has been used various fields such as the production of digital map, the modeling of 3D building and urban area, and analysis of communication network and environmental effect. In this study, the production cost of digital map by aerial LiDAR surveying were compared with the cost by aerial photograph surveying for analysis of economical efficiency. It is expected that the results of this study will be used base data for production, update, revision of digital map and curtail effect of national budget.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.1 s.5
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• pp.123-137
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• 1995

The digital information of Land is very important as the basis of geo-spatial information system. And the necessity of it is also increasing. But these days, every other institute that is needing digital map is seperately digitalizing lsnd information. So we need the stadard of accuracy evaluation and the method of hypothesis test for it. In this study, we check the standards of foreign countries and compare and analyze with our country's. After doing it, we suggest the direction for standard of digital map and statistical methods for testing accuracy evaluation about total maps that is digitized. Using hypergeometric distribution for considering consumer risk and producer risk, the statistical test can be for deciding optimal sampling map numbers by the total map and the agreement of contacting parties.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.433-437
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• 2003

고해상도 위성영상을 이용하여 수치표고모델(DEM) 및 정사영상을 제작해서 수치지도의 갱신 및 지형공간정보체계의 자료기반으로써 활용할 수 있다. 본 연구에서는 Sobel 연산자를 이용하여 경계추출을 행한 후 스크린 디지타이징 방법으로 경계선을 추출하였다 이렇게 추출된 벡터자료와 기존수치지도와의 중첩을 통해서 건물, 도로, 임야의 평균위치오차를 분석해 보았다. 평균위치오차가 공공측량의 작업규정에 대한 1 : 5,000 수치지도 제작의 허용오차범위에는 들지 못하였지만, 특정 부분의 지형·지물의 경우에는 수정, 보완이 가능한 것으로 나타났다. 그리고, 산악지역 보다는 도심지에서의 경계추출이 뚜렷하기 때문에 위치정밀도가 향상됨을 알 수 있었다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.5
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• pp.397-405
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• 2015

Currently, Korea's digital maps are being produced through traditional aerial photogrammetry methods. Aerial photogrammetry is the most economical way to produce a map of a wide area. However, timely survey is not allowed depends on weather condition and it is inefficient for small area surveying in economic point of view. Therefore, it costs too much and needs long time to produce a map for various small areas where are terrestrial changes for updating the map. In contrast, UAV photogrammetry is possible to work even in cloudy weather because of shooting at low altitude below the clouds. It also has excellent mobility and shoot quickly and well suited for small-scale mapping in several places by low cost. In this study, we produced an ortho-photo and digital map with the UAV photogrammetry method using SIFT and SfM algorithm and verified its accuracy to evaluate the applicability for future digital map updates. The accuracy was verified by comparing the results of the ground survey for check points selected on the digital map. Test results show small errors at ±2.6cm in X coordinates, ±2.8cm in Y coordinates and ±5.8cm in height and we could find a possibility that UAV photogrammetry would be fully applicable for digital map updating.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2009.04a
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• pp.87-89
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• 2009

A digital map is provided with 2 dimensions of tile based, a user is hard for decision-marking directly. In this study, we analyzed the present situation and characteristics of a digital map about a developed nation such as United States, England, Canada. As a result, American National Map and British Master Map are keeping continuity and up-to-date, included UFID, ISO, OGC referred to an international standard, and a digital map was made.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.4
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• pp.31-39
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• 2007

As the availability of images from airborne digital camera with high resolution is expanded, a lot of concern are shown about the production of orthoimage and digital map. This study presents the method of updating digital map using orthoimage from airborne digital camera image. Images were georectified using GPS surveying data. For the generation of orthoimage, Lidar DEM was used. The absolute positional accuracy of orthoimage was evaluated using GPS surveying data. And that of the building layer of digital map was estimated using the existed digital map at the scale of 1:1,000. The absolute positional accuracy of orthoimage was as followed: RMSE in X and Y were ${\pm}0.076m$ and ${\pm}0.294m$. The RMSE of the building layer were ${\pm}0.250m$ and ${\pm}0.210m$ in X and Y directions, respectively. The RMSE of the digital map using orthoimage from Aerial Digital Camera image fell within allowable error range established by NGII. Consequently, updating digital map using orthoimage from Aerial Digital Camera image can be applied to various fields including the construction of the framework data and the GIS of local government.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.269-275
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• 1997

Car Navigation System with Global Positioning System (GPS) can display position direction and the shortest cut of one's destination. The position datum for GPS in World Geodetic System 1984 (WGS-84) coordinates system need to transform Bessel coordinates system and process Map projection. Since 1987, GPS has used the WGS-84. WGS-84 is a geocentric equipotential ellipsoid of revolution which is defined four parameters. In this study, by comparing the digitized topographical map with the digital map of GPS datum we can consider the technique of WGS84 digital map.

• Spatial Information Research
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• v.7 no.1
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• pp.119-131
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• 1999

Various digital topographic maps including 1:1,000 and 1:5,000 have been produced for years and these digital maps are expected to serve a wide range of purposes. Most previous research about measuring positional accuracy for digital topographic maps depends int a method that acquires sample points from the tested map and compares to the corresponding known true locations using some statistics. Recently, a simple method for measuring positional accuracy for linear features is introduced but it has substantial problems applying to the spatial features such as roads, railroads, streams represented with double lines on the recently produced 1:1,000 and 1:5,000 digital topographic maps. This study develops and implements an effective method that measures road objects represented in the 1:5,000 digital topographic maps using a conventional GIS software. We also apply this method to a small study area located in Kangnam Gu, Seoul and illustrate the usefulness of this method.

• Korea journal of population studies
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• v.23 no.1
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• pp.181-196
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• 2000

본 연구는 센서스와 GIS가 어떻게 연계활용 될 수 있는지, 센서스 자료의 원할한 활용을 위한 전용의 수치지도가 왜 필요하며 그 제작은 어떠하여야 할지, 인구주택센서스 자료들의 발표기본단위가 될 센서스트랙과 블락 그룹이 왜 필요하며 어떻게 결정되어야 할 지에 관한 연구를 수행하였다. 본 연구의 결론에 의하면: 첫째, 센서스와 GIS가 결합됨으로 인하여 센서스의 방법이며 절차가 좀더 명확히 효율적으로 진행될 수 있고, 각종 분석과 표현이 다양해지고 용이해질 수 있으므로 이에 대한 고려와 연구가 요구되며, 둘째, 한국에서 제작되고 있는 각종의 수치지도들은 방대한 정보들을 포함하고 있어 제작기간이 길고 갱신상의 어려움이 존재하므로 센서스만을 위한 간결한 수치지도를 간략히 개편하여 활용하여도 좋다고 보며, 셋째, 센서스자료의 기본발표단위를 현재의 읍, 면, 동 보다 좀더 세분화된 센서스트랙과 블락그룹 등으로 지정하여야 자료의 유용도가 높아질 것으로 본다. 이들 경계선응 현재 인구주택총조사에 쓰이고 있는 조사구의 경계와 근린주구 이론과 아울러 여러 가지 물리적, 사회적, 경제적, 행정적 요소들을 감안하여 결정하는데, 한 개의 센서스트랙에 인구를 4,000명 정도로 하고 블락그룹은 1,500명 정도로 하되, 한 개의 센서스트랙에 1-9개의 블락그룹이 탄력성 있게 포함되도록 하면 좋을 것으로 본다.