• Title/Summary/Keyword: Erdas

Search Result 34, Processing Time 0.023 seconds

DEM Generation by the Matching Line Using Exterior Orientation Parameters of the IKONOS Geo Imagery (IKONOS 위성영상의 외부표정요소로부터 정합선 수립에 의한 DEM 생성)

  • Lee, Hyo-Seong;Ahn, Ki-Weon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.24 no.4
    • /
    • pp.367-376
    • /
    • 2006
  • This study determines the optimum polynomial of exterior orientation parameters(EOPs) as a function of line number of linear array scanner. To estimate priori EOPs, meta data of IKONOS scene and ground control points are used. We select a first order polynomial and a constant for position elements modeling and rotation elements modeling. Positioning accuracy of the determined EOPs is compared with that of RPCs bias-corrected by the least squares adjustment. There is almost no difference between accuracies of the two methods. To obtain digital elevation model(DEM), matching line is established by the EOPs. The DEM is compared with DEM generated by ERDAS IMAGINE software, which utilizes the bias-corrected RPCs. Height differences of DEMs by the two methods are ranged within a allowable standard deviation. The produced DEM, therefore, shows accuracy similar to the verified method.

A Study on Geometric Correction Method for RADARSAT-1 SAR Satellite Images Acquired by Same Satellite Orbit (동일궤도 다중 RADARSAT-1 SAR 위성영상의 기하보정방법에 관한 연구)

  • Song, Yeong-Sun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.28 no.6
    • /
    • pp.605-612
    • /
    • 2010
  • Numberous satellites have monitored the Earth in order to detect changes in a large area. These satellites provide orbit information such as ephemeris data, RPC coefficients and etc. besides image data. If we can use such orbit data afforded by satellite, we can reduce the number of control point for geo-referencing. This paper shows the efficient geometric correction method of strip-satellite RADARSAT-l SAR images acquired by same orbit using ephemeris data, single control point and virtual control points. For accuracy analysis of proposed method, this paper compared the image geometrically corrected by the proposed method to the image corrected by ERDAS Imagine.

Analysis of Land Suitability and Ecological Environment Using GIS Focused on the Evaluation Model for Designating of Natural Ecological Preservation Zone (지리정보체계를 이용한 생태환경분석 및 적지분석: 자연생태계 보전지역 설정 및 평가 모형을 중심으로)

  • Lee, Myungwoo
    • Journal of Environmental Impact Assessment
    • /
    • v.6 no.2
    • /
    • pp.61-80
    • /
    • 1997
  • This study tried to propose the guidelines for the ecological preservation zoning in Korea. So some related laws and regulations were inspected, which were Natural Environment Preservation Act, Nature Park Act, Cultural Asset Conservation Act, Forest Act and Urban Planning Act. In these acts, I could find several concepts related to the ecosystem that are described as the protection area. But there aren't detailed and practical characteristics in those concepts. So for making the practical concept of ecosystem preservation, I considered Multiple Use Module, Wildlife habitat model, and Environmental evaluation model. Thorough this step, the process and methodology was established for evaluating and analysing. The potentiality of the GIS system was inspected. So the TM5 scene of the site was acquired and processed by ER-Mapper, Idrisi, Arc/Info and Arcview. And several digitized data were input by scanning and vecterizing. The Erdas format was mostly exchangeable to any program. The site is the Byonsan Peninsula National Park. The forest stand information and topographic data were digitized, types of which are forest year, DBH, density, slope, aspect etc. And also the watershed boundary, roads and paths, natural and cultural resources were mapped and analysed. Modelling of preservation suitability found the dispersed patterns for the best suitable zone through all the site. And the development potential areas were checked on downwatershed. This patterns are thought to result from the forest location for the wildlife habitat and the low altitude and no-steep slopes for developing. And Early warning system concept was introduced by overlapping these two patterns on the both potential area. As the conclusions, I proposed that the preservation zone be assigned according to the watershed unit as the main ecosystem zone. This main area should be linked by the eco-corridor through the point type eco-system. Finally, I thought the comprehensive information system should be established for making the rational and efficient decision making in natural area.

  • PDF

Analysis of Landslide in Inje Region Using Aerial Photograph and GIS (항공사진과 GIS를 이용한 인제지역 산사태 분석)

  • Son, Jung-Woo;Kim, Kyung-Tak;Lee, Chang-Hun;Choi, Chul-Uong
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.17 no.2
    • /
    • pp.61-69
    • /
    • 2009
  • In mid-July, 2006 the torrential rainfall across Gangwon-do region caused 48 casualties and 1,248 houses submerged, resulting in damages with the restoration costs of 3 trillion and 512.5 billion won. This was because the topographic characteristics of Gangwon-do region for which mountainous areas mostly account increased the effects of landslide. In this study, the landslide region was shot using the PKNU No.4 system immediately after the occurrence of landslide in order to analyze it as objectively, exactly, and rapidly as possible. 1,054 areas with landslide occurrence were extracted by digitizing the shot images through visual reading after orthometric correction using ERDAS 9.1. Using the Arc GIS 9.2, a GIS program, hydrologic, topographic, clinical, geologic, pedologic aspects and characteristics of the landslide region were established in database through overlay analysis of digital map, vegetation map, geologic map, and soil map, and the status and characteristics of the occurrence of the landslide were analyzed.

  • PDF

Feature Extraction in an Aerial Photography of Gimnyeong Sand Dune Area by Texture Filtering (항공사진의 질감 분석을 통한 김녕사구지역의 지형지물 추출)

  • Chang Eun-Mi;Park Kyeong
    • Journal of the Korean Geographical Society
    • /
    • v.41 no.2 s.113
    • /
    • pp.139-149
    • /
    • 2006
  • Earlier research works focused on the seasonal patterns and bio-geochemical processes in sand dunes, and the satellite data and aerial photographs have been used only as a backdrop or for the multi-temporal delineation of sand dune area. In order to find the optimal way to extract features' characteristics, Gimnyeong sand dune area was selected as a study site. Field works have been carried out three times to collect ground control points and sand samples for laboratory analyses. The texture of sand dune is classified as fine sand, which has been derived from shell fragments. The sand dune penetrated into the island from northwest to southeast direction. An aerial photograph was re-sampled into one-meter resolution and rectified with software including Erdas Imagine and ENVI. Sub-scenes were chosen as samples for sand dune, urban area and rural area. K-group non-parametric analysis had been done for the geometric and spectral values of enclosed texture patches. Urban areas proved to have significant smaller patches than the others.

SGM Performance Improvement of Stereo Satellite Image with Classified Image and Edge Image (분류영상과 에지영상을 이용한 입체 위성영상의 SGM 성능개선)

  • Lee, Hyoseong;Park, Byungwook
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.38 no.6
    • /
    • pp.655-661
    • /
    • 2020
  • SGM (Semi Global Matching) can be used to find all the conjugate points between stereo images. Therefore, it enables high-density DSM (Digital Surface Model) production from high-resolution satellite images. However, water, shadows, and occlusion areas cause mismatching of the surrounding points in this method. Particularly, in buildings with large-parallax and elongated-shapes such as a Korean style apartment, it is difficult to reconstruct the 3D building even if the SGM method is applied to a high-resolution 50cm satellite image. This study proposed and performed the SGM technique with a classified image and an edge image from the IKONOS-2 satellite stereo-image with a 1m resolution to produce DSM. It was compared with the DSMs from the general SGM and the high-density ABM (Area Based Matching) matching of ERDAS software. The results of the apartment DSM by the proposed method were the best in the test area. As a result, despite the image having a resolution of 1m, the outline of the building DSM could be expressed more clearly than the existing method.

GIS technolgy for analysing regional geologic hazards (Landslides) (광역 지질재해분석(산사태)을 위한 GIS활용)

  • 김윤종;김원영;유일현
    • The Journal of Engineering Geology
    • /
    • v.2 no.2
    • /
    • pp.131-140
    • /
    • 1992
  • GIS(Geographic Information System) technology was applied for analysis of the potential degree of regional geologic hazard, especially landslide hazards in the suburb of Seoul City, whereby a regional geologic hazard map was produced. The factors causing a landslide such as slope geometry, geology, groundwater, soil property, rainfall and vegetation were incorporated through GIS in order to predict the potential hazards in this area. Cartographic simulation was finally made with these factors to produce a regional geologic hazard map. For this study, ARC/INFO and ERDAS systems were used in SUN 4-390 workstation.

  • PDF

Research and Development of a Geological Remote Sensing Information Extraction System

  • Zhengmin, He
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.1275-1277
    • /
    • 2003
  • This paper presents a geological remote sensing information extraction system, the aim of which is to provide practical models and powerful tools to extract geological information from remote sensing images for geological exploration applications. After reviewing and analyzing the existing methods for geological information extraction, we developed more than ten models to enhance and extract geological information, such as alteration information, linear features and special lithological characters. The system is developed based on Erdas Imagine using its programming language. It has been successfully used in the 'reat Investigation of Land and Natural Resources of China' program.

  • PDF

Remote sensing images and interpretation for 'Reverse Difference' phenomenon of the marine sediments At the CaMau tongue (extreme South Vietnam - Mekong Basin)

  • Cuong, Nguyen Tien;Kwon, Seung-Joon;Kim, Yong-Il
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.682-686
    • /
    • 2003
  • This paper is concerned with 'reverse difference' of marine sediments at the Camau tongue in the extreme south of Vietnam. We demonstrate the importance of remote sensing in geomorphology and marine geological application, using only visual evaluation and some data-processing techniques. In this paper, about 10,000 km$^2$ of the territorial water in the extreme south of Vietnam is being studied. We show that form and behavior of Mekong and its branch can be determined by visually interpreting remote sensing images and using ERDAS IMAGE 8.5 software. Besides, the 'reverse difference' phenomenon is explained by flows of Mekong river and its branches.

  • PDF

SEMI-AUTOMATIC EXTRACTION OF AGRICULTURAL LAND USE AND VEGETATION INFORMATION USING HIGH RESOLUTION SATELLITE IMAGES

  • Lee, Mi-Seon;Kim, Seong-Joon;Shin, Hyoung-Sub;Park, Jong-Hwa
    • Proceedings of the KSRS Conference
    • /
    • 2008.10a
    • /
    • pp.147-150
    • /
    • 2008
  • This study refers to develop a semi-automatic extraction of agricultural land use and vegetation information using high resolution satellite images. Data of IKONOS satellite image (May 25 of 2001) and QuickBird satellite image (May 1 of 2006) which resembles with the spatial resolution and spectral characteristics of KOMPSAT3. The precise agricultural land use classification was tried using ISODATA unsupervised classification technique and the result was compared with on-screen digitizing land use accompanying with field investigation. For the extraction of vegetation information, three crops of paddy, com and red pepper were selected and the spectral characteristics were collected during each growing period using ground spectroradiometer. The vegetation indices viz. RVI, NDVI, ARVI, and SAVI for the crops were evaluated. The evaluation process is under development using the ERDAS IMAGINE Spatial Modeler Tool.

  • PDF