• Journal of the Korean Geographical Society
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• v.37 no.5
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• pp.511-521
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• 2002

Coastal sand dunes in West coast of Korea are under stress. Due to the newly constructed Seohaean(West Coast) Highways, the number of visitors and the anthropogenic pressures will keep rising in near future. Sea level rise due to the global warming may cause a lot of damage to the natural resources and residents of coastal area. Therefore, many countries including United States are doing nationwide coastline survey using highly sophisticated methodology. In this study, high resolution IKONOS satellite images along with aerial photographs taken since 1960's have been sequentially analyzed using GIS software (Erdas Imagine 8.3). Onsite monitoring has been performed at the 31 measuring points in 10 beaches since the May of 2001 in order to measure the sand budget. Post-construction monitoring after installation of sand fences is also being done on sites regularly. Restoration works seem to be effective at this moment.

• The Journal of Engineering Geology
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• v.26 no.1
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• pp.23-32
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• 2016

This study evaluates landslide susceptibility using statistical analysis by SVM (support vector machine) and the illite index of clay minerals extracted from ASTER(advanced spaceborne thermal emission and reflection radiometer) imagery which can be use to create mineralogical mapping. Landslide locations in the study area were identified from aerial photographs and field surveys. A GIS spatial database was compiled containing topographic maps (slope, aspect, curvature, distance to stream, and distance to road), maps of soil properties (thickness, material, topography, and drainage), maps of timber properties (diameter, age, and density), and an ASTER satellite imagery (illite index). The landslide susceptibility map was constructed through factor correlation using SVM to analyze the spatial database. Comparison of area under the curve values showed that using the illite index model provided landslide susceptibility maps that were 76.46% accurate, which compared favorably with 74.09% accuracy achieved without them.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.2
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• pp.153-158
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• 2006

A new High Resolution Geometry or HRG imaging instrument is developed by CNES to be carried on-board SPOT 5. The HRG instrument offers a higher ground resolution than that of the HRV/HRVIR on SPOT 1 - 4 satellites. The field width of HRG is 60 km, same as SPOT constellation. With two HRG instruments, a maximum swath of 120 km at 5 m resolution can be achieved. The generation of Digital Elevation Models (DEMs) from satellite stereo images scores over conventional methods of DEM generation using topographic maps and aerial photographs. This global availability of satellite images allows for quicker data processing for an equivalent area. In this study, a HRG stereo images of SPOT 5 over JECHEON has been used with Leica Photogrammetry Suite OrthoBASE Pro tool for the creation of a digital elevation model (DEM). The extracted DEM was compared to the reference DEM obtained from the contours of digital topographic map.

• Korean Journal of Remote Sensing
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• v.4 no.1
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• pp.31-40
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• 1988

Low-cost microcomputer systems can be assembled which possess computing power, color display, memory, and storage capacity approximately equal to graphic workstactions. A low-cost, flexible, and user-friendly IBM/PC/XT/AT based image processing system has been developed and named as KMIPS(KAIST (Korea Advanced Institute of Science & Technology) Map and Image Processing Station). It can be easily utilized by the resource managers who are not computer specialists. This system can: * directly access Landsat MSS and TM, SPOT, NOAA AVHRR, MOS-1 satellite imagery and other imagery from different sources via magnetic tape drive connected with IBM/PC; * extract image up to 1024 line by 1024 column and display it up to 480 line by 672 column with 512 colors simultaneously available; * digitize photographs using a frame grabber subsystem(512 by 512 picture elements); * perform a variety of image analyses, GIS and terrain analyses, and display functions; and * generate map and hard copies to the various scales. All raster data input to the microcomputer system is geographically referenced to the topographic map series in any rater cell size selected by the user. This map oriented, georeferenced approach of this system enables user to create a very accurately registered(.+-.1 picture element), multivariable, multitemporal data sets which can be subsequently subsequently subjected to various analyses and display functions.

• Korean Journal of Remote Sensing
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• v.8 no.2
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• pp.79-91
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• 1992

With recent development in spaceborne imaging radar system, there are growing interests using satellite synthetic aperture radar(SAR) data in various applications. This study attempted to identify the relationships between several forest stand characteristics and radar backscatter, measured from space altitude altitude at three incidence angles. Shuttle Imaging Radar-B(SIR-B) data were collected over a forested area in northern Florida in October, 1984. By using various sources of reference data (forest type maps, inventory records, aerial photographs, and Landsat Thematic Mapper data), about 400 forest stands of known characteristics were carefully located in the radar data. Relative radar backscatter for the three incidence angles of SIR-B data were compared with known forest stand parameters such as mean tree height, diameter at breast height(DBH), stand density, biomass, and relative amount of understory vegetation. The results show that these stand parameters have statistically significant correlations with the radar backscatter. In addition, the SIR-B radar backscatter from a certain stand parameter turned out differently at the three different incidence angles. Finally, the types and characteristics of currently available satellite SAR data are discussed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.2
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• pp.15-30
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• 2014

Systematic management of wetlands should be a priority to build the data for the extent and distribution of wetlands all over the country. However there are no clear guidelines for the wetland boundary delineation, so researchers have to determine the boundary of wetlands in each different way. As a result, it is very difficult to identify the extent and distribution of wetlands. This study proposes applicable criteria of setting boundary of wetlands which consider their wetland vegetation and geographical characteristics, according to wetland classification. The proposed site in this study is selected wetlands that represent each wetland type and have been ecologically well preserved like the wetland protected areas. GIS data for setting the boundary of wetlands selected were land-cover maps, aerial photographs, high resolution satellite images, and digital topographic maps. In this study, 'wetland unit determination' of the Washington State Wetlands Rating System(WSDE, 1993) and the concept of 'Wetland and Deep-water Habitats' was suggested by Wetland Delineation Manual(USACE, 1987) were used as criteria for setting the boundary of wetlands. As a result, it was found that the boundary of wetlands could be, in general, set consistently. Also, it seemed possible to set systematic and standardized boundary of wetlands and to provide more objective data for establishing national wetland policies, if maps of wetlands are made and an investigation of wetlands is implemented according to the criteria.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.393-398
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• 2006

Currently, 54 kinds of digital maps are provided by National Geographic Information Clearinghouse and the majority of those maps are based on aerial photographs or satellite image. The digital maps which symbolize and simplifies the topography and objects from ortho-photos does not reflect the objects 'shapes and facilities' changes. Especially, underground structures and complex building shapes are not correctly identifies by ortho-photos. Furthermore, the 1/1,000 and 1/500-1/2,500 maps for urban area produced by some local government or public organizations have detailed information with high precision, it is not easy to update the information due to the frequent changes of structures in the city. Although some efforts to solve this problem such as conducting field survey and shorten the survey period were tried, it is not the fundamental solution due to the high cost. Therefore, in this study, a realtime renewal and update of digital map using general survey are suggested. By assigning absolute coordinates to the general survey products and matching with digital maps, it is possible to update the digital map economically and rapidly. In addition, it is suggested that the construction of DB for general survey and sharing among survey companies to solve the duplicated survey.

• Journal of Korean Society for Geospatial Information Science
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• v.2 no.2 s.4
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• pp.43-53
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• 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 KSRS Conference
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• 2004.10a
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• pp.314-317
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• 2004

The aim of this study was to evaluate the susceptibility from landslides in the Lai Chau region of Vietnam, using Geographic Information System (GIS) and remote sensing data, focusing on the relationship between tectonic fractures and landslides. Landslide locations were identified from an interpretation of aerial photographs and field surveys. Topographic and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS data and image processing techniques, and a scheme of the tectonic fracturing of the crust in the Lai Chau region was established. In this scheme, Lai Chau was identified as a region with low crustal fractures, with the grade of tectonic fracture having a close relationship with landslide occurrence. The factors found to influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature, distance from drainage, lithology, distance from a tectonic fracture and land cover. Landslide prone areas were analyzed and mapped using the landslide occurrence factors employing the probability-likelihood ratio method. The results of the analysis were verified using landslide location data, and these showed a satisfactory agreement between the hazard map and existing landslide location data.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.302-305
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• 2004

The aim of this study is to apply and crossvalidate a spatial logistic multiple-regression model at Boun, Korea, using a Geographic Information System (GIS). Landslide locations in the Boun area were identified by interpretation of aerial photographs and field surveys. Maps of the topography, soil type, forest cover, geology, and land-use were constructed from a spatial database. The factors that influence landslide occurrence, such as slope, aspect, and curvature of topography, were calculated from the topographic database. Texture, material, drainage, and effective soil thickness were extracted from the soil database, and type, diameter, and density of forest were extracted from the forest database. Lithology was extracted from the geological database and land-use was classified from the Landsat TM image satellite image. Landslide susceptibility was analyzed using landslide-occurrence factors by logistic multiple-regression methods. For validation and cross-validation, the result of the analysis was applied both to the study area, Boun, and another area, Youngin, Korea. The validation and cross-validation results showed satisfactory agreement between the susceptibility map and the existing data with respect to landslide locations. The GIS was used to analyze the vast amount of data efficiently, and statistical programs were used to maintain specificity and accuracy.