• Korean Journal of Remote Sensing
• /
• v.18 no.6
• /
• pp.327-336
• /
• 2002

Ever since high resolution satellites were launched, high-resolution satellite images have been utilized in many areas. This paper proposed methods of generating simulated satellite image using DEM(Digital Elevation Model) and digital image such as aerial photograph. There are two methods proposed in the paper: one is Direct-Indirect method and the other Indirect-Indirect, method. It is assumed that satellite attitude is not changing and perspective center is moving in the direction of flight while image is captured. The proposed methods were implemented with aerial photograph, DEM data, arbitrary orbit parameters and attitude parameters of high resolution satellite image under generation. Furthermore, for the stereo viewing, different orientation parameters and perspective center were tested for generating simulated satellite image. In addition, the quality and accuracy of the simulated satellite image generated by the proposed methods were analyzed.

• Korean Journal of Remote Sensing
• /
• v.35 no.3
• /
• pp.471-482
• /
• 2019

The mission of the high-resolution camera for the lunar exploration is to provide 3D topographic information. It enables us to find the appropriate landing site or to control accurate landing by the short distance stereo image in real-time. In this paper, the ground verification and analysis system using the multi-application stereo camera to develop the high-resolution camera for the lunar exploration are proposed. The mission test items and test plans for the mission requirement are provided and the test results are analyzed by the ground verification and analysis system. For the realistic simulation for the lunar orbiter, the target area that has similar characteristics with the real lunar surface is chosen and the aircraft flight is planned to take image of the area. The DEM is extracted from the stereo image and compose three dimensional results. The high-resolution camera mission requirements for the lunar exploration are verified and the ground data analysis system is developed.

• Proceedings of the KSRS Conference
• /
• 2009.03a
• /
• pp.35-38
• /
• 2009

본 논문은 KOMPSAT-2, KOMPSAT-3 등과 같은 고해상도 위성영상의 정사보정 방법과 그에 따른 시험용 소프트웨어 개발을 목표로 한다. 정사보정은 위성 카메라의 자세나의 지표의 피복인위에 의하여 발생하는 인위를 제거하여 정사투영 된 특성을 갖는 영상을 구하는 과정을 말한다. 정사보정을 위해서는 위성 카메라의 기하학적인 특성과 지표면의 관계식을 나타내는 공선조건 식으로부터 지상기준점 및 수치표고모델을 통하여 구해진다. 본 논문에서는 고해상도 위성영상의 정사보정 방법을 구현하고, 실제 위성영상 데이터에 적용하여 구현된 소프트웨어의 성능을 평가한다.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
• /
• 2008.10a
• /
• pp.247-248
• /
• 2008

본 연구는 IKONOS 입체 위성영상에서 정합시간 단축을 위한 인터벌 정합방법을 제안하였다. 그 결과, 산림지역을 제외한 나머지 지역에서 인터벌을 주지 않고 정합한 경우와 큰 차이를 보이지 않았다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.30 no.6_1
• /
• pp.583-590
• /
• 2012

This study proposes fusion image matching method according to land cover property to generate a detailed DEM using the high resolution IKONOS-2 stereo pair. A classified image, consists of building, crop-land, forest, road and shadow-water, is produced by color image with four bands. Edges and points are also extracted from panchromatic image. Matching is performed by the cross-correlation computing after five classes are automatically selected in a reference image. In each of building class, crop-land class, forest class and road class, matching was performed by the grid and edge, only grid, only grid, grid and point, respectively. Shadow-water class was excepted in the matching because this area causes excessive error of the DEM. As the results, edge line, building and residential area could be expressed more dense than DEM by the conventional method.

• Journal of the Korean Geographical Society
• /
• v.48 no.3
• /
• pp.321-335
• /
• 2013

High resolution data for the coastal sand beach during short-term in Jinbok-ri, Uljin-gun, Gyeongsangbuk-do are obtained by terrestrial LiDAR. The micro-geomorphological changes of 8 times before and after the strong low-pressure events during June to September, 2009 and changes under the various environments of wave-energy are investigated in the study. The obvious geomorphological changes between the northern and southern sand beach in Jinbok-ri are revealed by terrestrial LiDAR as well as by grain size analysis. The strong waves by the typhoons decrease the area and volume of the beach, and especially the area is largely influenced. The erosive and depositional processes dominate the northern and southern sand beach, respectively, after high wave in September. These results suggest that lots of sand grains in the beach are largely re-transported within the beach rather than offshore.

• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06b
• /
• pp.279-282
• /
• 2010

최근 단일 고해상도 위성영상과 건물과 지형에 대한 정보를 가지고 있는 수치지도(DEM:Digital Elevation Model)를 이용하여 3차원 영상으로 구축하는 연구가 많이 이루어지고 있다. 3차원영상을 구축하기 위해서는 건물과 지형의 위치, 크기, 형상에 관한 정보가 필요하나 위성영상만으로는 구하기가 어려워 수치지도를 활용한다. 본 논문에서는 수치지도를 이용하여 3차원 건물과 지형의 고도 정보를 추출하고, 위성영상과 Snake 모델을 이용하여 반자동으로 추가적인 건물 높이와 바닥면에 대한 정보를 추출하여, 3차원 영상을 생성 하는 방법을 제안한다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2004.05b
• /
• pp.1157-1161
• /
• 2004

본 연구의 목적은 TIN(Triangulated Irregular Network)을 생성하고, GIS 기반의 지형도, 토양도 및 토지 이용도를 이용하여 WMS 6.1 모델로 홍수위별 홍수범람도를 작성하는데 있으며, 대상유역은 양화천 유역의 세1지류인 매류천과 안금천, 대신천 유역으로 선정하였다. 대상유역내의 실제 홍수범람자료를 조사하였고, Arc-view를 이용하여 DEM (Digital Elevation Model), 토지 이용도, 토양도의 GIS DB를 구축하였다. 본 연구에서 50년 빈도의 홍수위를 분석한 결과 모형을 사용한 피해 예상 지역과 실제 홍수위로 인한 피해지역이 유사하게 나타났다. 20년 빈도 홍수위에서 500년 빈도 홍수위로의 증가로 인한 침수면적의 증가율은 매류천이 가장 작았고, 안금천이 가장 컸다. 본 연구에서는 기존의 저해상도 DEM이 제외지 및 하천 제방의 영향을 전혀 고려하지 못 하였던 점을 개선하여 저해상도 DEM과 항공사진 측량자료인 고해상도 DEM을 합성하여 더욱 신뢰성 있는 홍수범람도를 작성하였다. 이 결과는 대상유역의 홍수발생시 홍수예경보 및 재해발생시 대피장소의 결정과 시설물 관리업무의 기초 자료로 활용할 수 있을 뿐만 아니라 홍수피해의 판단자료로 이용될 수 있을 것이다.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.13 no.2
• /
• pp.54-63
• /
• 2010

The intensive rainfall over 455 mm occurred between on 9 to 14 July 2009 triggered debris flows around the mountain area in Jecheon County. We mapped the debris flow area and estimated the debris flow volume using a high resolution digital elevation model (DEM) generated respectively from terrestrial LiDAR (Light Detection And Ranging) and topographic maps. For the LiDAR measurement, the terrestrial laser scanning system RIEGL LMS-Z390i which is equipped with GPS system and high-resolution digital camera were used. After the clipping and filtering, the point data generated by LiDAR scanning were overlapped with digital map and produced DEM after debris flow. The comparison between digital map and LiDAR scanning result showed the erosion and deposition volumes of about $17,586m^3$ and $7,520m^3$, respectively. The LiDAR data allowed comprehensive investigation of the morphological features present along the sliding surface and in the deposit areas.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.28 no.2
• /
• pp.265-271
• /
• 2010

This paper discusses a new software package, DEM_Comp, developed for effectively compressing large digital elevation model (DEM) data sets based on Lempel-Ziv-Welch (LZW) compression and Huffman coding. DEM_Comp was developed using the $C^{++}$ language running on a Windows-series operating system. DEM_Comp was also tested on various test sites with different territorial attributes, and the results were evaluated. Recently, a high-resolution version of the DEM has been obtained using new equipment and the related technologies of LiDAR (LIght Detection And Radar) and SAR (Synthetic Aperture Radar). DEM compression is useful because it helps reduce the disk space or transmission bandwidth. Generally, data compression is divided into two processes: i) analyzing the relationships in the data and ii) deciding on the compression and storage methods. DEM_Comp was developed using a three-step compression algorithm applying a DEM with a regular grid, Lempel-Ziv compression, and Huffman coding. When pre-processing alone was used on high- and low-relief terrain, the efficiency was approximately 83%, but after completing all three steps of the algorithm, this increased to 97%. Compared with general commercial compression software, these results show approximately 14% better performance. DEM_Comp as developed in this research features a more efficient way of distributing, storing, and managing large high-resolution DEMs.