• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.337-339
• /
• 2003

This paper describes the SAR geocoding module, which is the sub-module of a IRHIS ('Integrated RS s/w for High resolution satellite ImageS'): package of 'Development of High Resolution Satellite Image Processing Technique' project in Electronics and Telecommunications Research Institute (ETRI). The function of this module is following. 1) Orbit Type : ERS1/ERS2, RADARSAT 2) Data Format : SAR CEOS Format(Single Look Complex) 3) Function: - Geocode : Generate a map projected SAR image based on only orbit information - Orthorectify: Generate a rigorous geocoded SAR image with a DEM information In this paper, we briefly describe the algorithm that is adopted to the functions, and component architecture.

• Korean Journal of Remote Sensing
• /
• v.22 no.5
• /
• pp.351-356
• /
• 2006

Based on current practical needs for geo-spatial information on mobile platform, the main theme of this study is a design and implementation of dynamic 3D terrain rendering system using spaceborne imagery, as a kind of texture image for photo-realistic 3D scene generation on mobile environment. Image processing and 3D graphic techniques and algorithms, such as TIN-based vertex generation with regular spacing elevation data for generating 3D terrain surface, image tiling and image-vertex texturing in order to resolve limited resource of mobile devices, were applied and implemented by using graphic pipeline of OpenGL|ES (Embedded System) API. Through this implementation and its tested results with actual data sets of DEM and satellite imagery, we demonstrated the realizable possibility and adaptation of complex typed and large sized 3D geo-spatial information in mobile devices. This prototype system can be used to mobile 3D applications with DEM and satellite imagery in near future.

• Journal of Information Technology Services
• /
• v.17 no.4
• /
• pp.139-150
• /
• 2018

This paper investigated the human distribution in subway station areas in Seoul, using geotweets and subway ridership data. Eight stations were selected from the districts of Gangnam and Gangbuk. Geotweets located within a 600-meter radius of the central coordinates of each station were extracted, and distances between the center of station and each tweet location were calculated. Donut-shaped dimension and pie-shaped dimension were generated, using the Haversine distance formula and the Azimuth angle formula respectively. By combining the two dimensions, Dartboard-shaped space division is created. Popular places within the subway station areas identified from this research are almost the same as the current well-known popular places, and this is an important case showing that people send tweets from various places where they engage in daily activities. We expect this study can be a methodological guideline for social scientists who use spatio-temporal or GPS data for their research.

• Journal of Korean Society for Geospatial Information Science
• /
• v.2 no.2 s.4
• /
• pp.43-53
• /
• 1994

GSIS(geo-spatial information system), particularly when utilized in hazard management decision, is one of hazard analysis tool. Data of GSIS input from digitizing or scanning of map or aerial photos. This paper focuses upon the hazard prediction in GSIS and RS analysis to assess map, aerialphotos, satellite imagery and soil map. This study found computation of hazard area analysis. the results is formed as raster data model of quadtree. Authors knew more accurate results of overlay. This paper shows building up integrated data base as well as search of hazard area in aerial photographs.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
• /
• 2008.06a
• /
• pp.143-149
• /
• 2008

전 지구적 기온상승으로 인하여 해수면 상승 및 자연생태계가 파괴되고 있다. 이에 Geo 관련 연구자들은 지구 온난화, 이산화탄소 배출량, 미세먼지 확산 등의 방대한 지구환경정보를 공유 및 교환하고 활발한 지식 교류를 하기 위한 포털 환경이 요구되고 있다. 국외 여러 환경단체들은 이러한 포털 환경구축을 통해 지구 환경정보를 연구하고 있다. 한국에서도 지구온난화 영향분석, 미세먼지 확산분석, 이산화탄소 배출량 분석 지상 식생변화 모니터링 등의 분야에서 위성 관측 영상 및 지구환경자료를 이용한 서비스가 더욱 절실하다. e-Science 환경 구축의 대표 응용 분야 중의 하나로 발전, 확산시킬 필요성 때문에 정확하고 방대한 지식정보의 신속한 처리 및 서비스를 할 수 있는 GeoGrid 기반 기술 개발 방법과 환경 구축 방법에 대해 연구하였다.

• Spatial Information Research
• /
• v.20 no.2
• /
• pp.129-136
• /
• 2012

Recently international organizations such as ISO/TC211, OGC, INSPIRE (Infrastructure for Spatial Information in Europe) make an effort to share geospatial data using semantic web technologies. In addition, smart phone and social networking services enable community-based opportunities for participants to share issues of a social phenomenon based on geographic area, and many researchers try to find a method of extracting issues from that. However, serviceable spatial ontologies are still insufficient at application level, and studies of spatial information extraction from SNS were focused on user's location finding or geocoding by text mining. Therefore, a study of extracting spatial phenomenon from social media information and converting it into geosemantic knowledge is very usable. In this paper, we propose a framework for extracting keywords from micro-blog, one of the social media services, finding their relationships using data mining technique, and converting it into spatiotemopral knowledge. The result of this study could be used for implementing a related system as a procedure and ontology model for constructing geoseem antic issue. And from this, it is expected to improve the effectiveness of finding, publishing and analysing spatial issues.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2010.04a
• /
• pp.285-287
• /
• 2010

It is recently enlarged to necessity of 3D spatial information model in urban areas. and in order to that, It is increased to use the terrestrial LiDAR. The Point clouds which are received by terrestrial LiDAR take a relateive coordinate. For transform into absolute coordinate, it carry out GPS surveying. However, it is difficult to geo-referencing of point clouds using the GPS due to high buildings and facilities in urban area. This study suggests a methodology, that is geo-referencing of point clouds which is received from terresstrial LiDAR in urban area and then verified accuracy of geo-referencing of point clouds. In order to geo-Referencing of point clouds which are received in Engineering building of Yonsei Univ., it was be setout through GPS surveying, and then obtained absolute coordinate of real building. Using this coordinate, It was operated geo-referencing of point clouds, verified accuracy between check point and geo-referenced point clouds. As a result, RMSE of check point shows that GPS surveying is 6.9~8.0cm.

• Proceedings of the KSRS Conference
• /
• 2002.10a
• /
• pp.516-516
• /
• 2002

With the wide usage of LiDAR data and high-resolution satellite image, 3D modeling of buildings in urban areas has become an important research topic in the photogrammetry and computer vision field for many years. However the previous modeling has its limitations of merely texturing the image to the DSM surface of the study area and does not represent the relief of building surfaces. This study is focused on presenting a system of realistic 3D building modeling from consecutive stereo image sequences using digital camera. Generally when acquiring images through camera, various parameters such as zooming, focus, and attitude are necessary to extract accurate results, which in certain cases, some parameters have to be rectified. It is, however, not always possible or practical to precisely estimate or rectify the information of camera positions or attitudes. In this research, we constructed the collinearity condition of stereo images through extracting the distinctive points from stereo image sequence. In addition, we executed image matching with Graph Cut method, which has a very high accuracy. This system successfully performed the realistic modeling of building with a good visual quality. From the study, we concluded that 3D building modeling of city area could be acquired more realistically.

• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.717-720
• /
• 2005

Recently as large sized urban development and the city ward drifting of population are caused, the urban surface temperature is raised very seriously and rapidly. These artificial developments have destroyed the inner and outer landscapes such as topography and have changed complex local climate such as a sudden rise in temperature, the change of wind field and air pollution. In order to clarify this problem visually, the studies on extracting the thermal infrared and the characteristic analysis of local climate in urban area had been performed by using the sixth band of Landsat TM and ETM+. However, there is a need to alternate Landsat TM and ETM+ because these satellite images are not applied any more. Therefore, in this paper it is proposed to use 2 Aster image (2004.4.17 daily 2b03, 2004.10.10 night 2b03) of EOS AM and to extract the surface temperature. Also, the pattern of surface temperature in urban area and the application possibility in local climate study are proposed by verifying the correlation with A WS data. Also, IKONOS image was used to figure out the artificial development area in visual.

• Korean Journal of Remote Sensing
• /
• v.24 no.2
• /
• pp.179-188
• /
• 2008

This study aims for generating a city spatial model required for the creation of a 3D noise map. In this study, we propose an efficient method to generate 3D models of the terrain and buildings using only a digital map and draft maps previously established without using any sensory data. The terrain model is generated by interpolating into a grid the elevation values derived from both the contour lines and the elevation point of the digital map. Building model is generated by combining the 2D building boundaries and the building elevations extracted from the digital map and the draft map, respectively. This method has been then applied to a digital map and three sets of draft maps created in the different times. covering the entire area of Yeongdeungpo-gu. The generated city spatial model has been successfully utilized for the noise analysis and the 3D visualization of the analysis results.