• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.381-384
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• 2004

The goal of this study is to generate a landslide susceptibility map using GIS(geographic information system) based method. A simple and efficient algorithm is proposed to generate a landslide susceptibility map from DEM(digital elevation model) and existing maps. The categories of controlling factors for landslides, aspect of slope, soil, topographical index, landuse, vegetation are defined, because those factors are said to have relevance to landslide and are easy to obtain theirs sources. The weight value for landslide susceptibility is calculated from the density of the area of landslide blocks in each class. Finally, a map of susceptibility zones is produced using the weight value of all controlling factors, and then each susceptibility zone is evaluated by comparing with the distribution of each controlling factor class.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.322-330
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• 1994

The Universal Soil Loss Equation (USLE) has been widely used to predict long-term soil loss by incorporating several erosion factors, such as rainfall, soil, topography, and vegetation. This study is aimed to introduce the LISLE within geographic information system(GIS) environment. The Kwangneung Experimental Forest located in Kyongki Province was selected for the study area. Initially, twelve years of hourly rainfall records that were collected from 1982 to 1993 were processed to obtain the rainfall factor(R) value for the LISLE calculation. Soil survey map and topographic map of the study area were digitized and subsequent input values(K, L, S factors) were derived. The cover type and management factor (C) values were obtained from the classification of Landsat Thematic Mapper(CM) satellite imagery. All these input values were geographically registered over a common map coordinate with $25{\times}25m^2$ ground resolution. The USLE was calculated for every grid location by selecting necessary input values from the digital base maps. Once the LISLE was calculated, the resultant soil loss values(A) were represented by both numerical values and map format. Using GIS to run the LISLE, it is possible to pent out the exact locations where soil loss potential is high. In addition, this approach can be a very effective tool to monitor possible soil loss hazard under the situations of forest changes, such as conversion of forest lands to other uses, forest road construction, timber harvesting, and forest damages caused by fire, insect, and diseases.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.3
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• pp.385-392
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• 2010

A LiDAR technique has the merits that survey engineers can get a large number of measurements with high precision quickly. Aerial photos and satellite sensor images are used for generating 3D spatial images which are matched with the map coordinates and elevation data from digital topographic files. Also, those images are used for matching with 3D spatial image contents through perspective view condition composed along to the designated roads until arrival the corresponding location. Recently, 3D aviation image could be generated by various digital data. The advanced geographical methods for guidance of the destination road are experimented under the GIS environments. More information and access designated are guided by the multimedia contents on internet or from the public tour information desk using the simulation images. The height data based on LiDAR is transformed into DEM, and the real time unification of the vector via digital image mapping and raster via extract evaluation are transformed to trace the generated model of 3-dimensional downtown building along to the long distance for 3D tract model generation.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.3
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• pp.11-22
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• 2005

It is necessary to arrange and analyze the collected research date to get regularity such as characteristics, merits and demerits, and possibility in city when constructing land information by analyzing linkage and utilization of cadastral information as the fundamental data for land information around the acreage of a lot and by expressing the purpose of each digital data construction with map. In short, that is the work to classify data, to make chart or map, or to analyze using statistical technique. Some information in land utilization had been used by computerization, but several problems were found in common use of total divisions. The most important problem is, in the case of drawing information, that topographical map with building boundary and land registration map with acreage boundary cannot be used together. In the case of property information, common utilization of property information that is basically needed and standard measurement of usage classification are necessary. The characteristics of the land usage data by the rearrangement of the cadastral information. etc. is presented as the basic data for the land information orientation, and the analyzing result of the data should be expressed and controlled on the map as the fundamental survey for the establishment of the land information oriented planning supports the physical space planning of the land cadaster finally. In this research, the problem in establishing current land information around acreage of a lot was found to research data to be needed in land information for utilizationof space based digital information, and was studied the method in relation to GIS.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.1
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• pp.57-67
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• 2013

In Korea, there are debris-flow disasters induced by typhoon and localized torrential rainfall annually. There are particularly extensive debris-flow disasters in Gangwon-do because of its geomorphological characteristics; the extensive coverage of mountainous region, steep slope, and shallow soil. In this paper, we constructed a GIS database about topological characteristics of debris-flow basin in Gangwon-do by years of field survey. Also, we conducted frequency analysis based on this database with the digital forest type map and the digital soil map. We analyzed frequencies of debris-flow by simple count for topological characteristics, whereas we analyzed by considering an area ratio based on GIS for physiognomic and geologic characteristics. We used slope, aspect, width, depth and destruction shapes for analysis about topological characteristics of debris-flow basin. Also we used attributes of forest physiognomy, diameter, age, and density about physiognomic characteristics, and i n terms of geologic characteristics, we used attributes of drainage class, effective soil depth, subsoil properties, subsoil grave content, erosion class, parent material of soil, and topsoil properties. In consequence, we figured out topographic, forest physiognomic, and geologic characteristics of debris-flow basin. This result is applicable to establish a rational disaster prevention policy as a fundamental information.

• Journal of Korea Spatial Information System Society
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• v.12 no.1
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• pp.57-65
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• 2010

In this study, disaster damage investigation system was developed using high resolution satellite images and GIS technique to afford effective damage investigation system for widely disaster damaged area. Study area was selected in Bonghwa, Gyungsangbukdo where high magnitude of damages from torrential rain has occurred at July in 2008. GIS DB was built using 1:5,000 topographic map, cadastral map, satellite image and aerial photo to apply for investigation algorithm. Disaster damage investigation system was developed using VB NET languages, ArcObject component and MS-SQL DBMS for effective management of damage informations. The system can finding damaged area comparing pre- and post-disaster images and drawing damaged area according to the damage item unit. Extracted object was saved in Shape file format and overlayed with background GIS DB for obtaining detail information of damaged area. Disaster damage investigation system using high resolution spatial images can extract damage information rapidly and highly reliably for widely disaster areas. This system can be expected to highly contributing to enhance the disaster prevention capabilities in national level field investigation supporting and establishing recovery plan etc. This system can be utilized at the plan of disaster prevention through digital damage information and linked in national disaster information management system. Further studies are needed to better improvement in system and cover for the linkage of damage information with digital disaster registry.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.2
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• pp.46-64
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• 2003

The vector shaped object is generally very long (hundreds or thousands of kilometers) and very narrow (10-100 meters). Image mapping techniques and tools for these objects should be totally different from the traditional area-based targets. Acknowledging these unique characteristics of the vector shaped object, a motion picture mapping system has been developed by combining internet GIS technology with airborne video. In particular, integration between airborne video and digital maps took advantage of each component, and enabled the landscape structure to be visualized, interacted with and deployed all on the Web. The motion picture maps provided a completely new means for disseminating information for area-wide landscape in a visual and interactive manner to the general public while digital map with location information revealed successfully the major parameters that influence an area-wide spatial structure in the study area. The remote video approach breaks down the usual concept of image mapping in a conventional cartography. As a result, the research findings have established the new concept of 'internet airborne video mapping for vector shaped object', proposed as an initial aim of this paper. It would playa crucial role in improving the quality of public information service if the mapping system is operationally introduced into the Government since the highly user-friendly moving picture provides a completely new means for disseminating spatia) information for vector shaped object.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.1
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• pp.139-147
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• 2023

As heavy precipitation rates have increased due to climate change, the risk of landslides has also become greater. Studies in the field of disaster risk assessment predominantly focus on evaluating intrinsic importance represented by the use or role of facilities. This work, however, focused on evaluating risks according to the external conditions of facilities, which were presented via debris flow simulation. A random walk model (RWM) was partially improved and used for the debris flow simulation. The existing RWM algorithm contained the problem of the simulation results being overly concentrated on the maximum slope line. To improve the model, the center cell height was adjusted and the inertia application method was modified. Facility information was collected from a digital topographic map layer. The risk level of each object was evaluated by combining the simulation result and the digital topographic map layer. A risk assessment technique suitable for the polygon and polyline layers was applied, respectively. Finally, by combining the evaluated risk with the attribute table of the layer, a system was prepared that could create a list of objects expected to be damaged, derive various statistics, and express the risk of each facility on a map. In short, we used an easy-to-understand simulation algorithm and proposed a technique to express detailed risk information on a map. This work will aid in the user-friendly development of a debris flow risk assessment system.

• Spatial Information Research
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• v.10 no.1
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• pp.139-152
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• 2002

The purpose of this study is to estimate temporal soil loss change according to long-term land cover changes using G1S and RS. Revised USLE(Universal Soil Loss Equation) factors were prepared by using point rainfall data, DEM(Digital Elevation Model), soil map and land cover map. During the past two decades, land cover changes were traced by using Landsat MSS and TM data. As a result, forest area in 2000 has decreased 25.3 $km^2$ compared with that in 1990. Soil loss has decreased 3751.2 tou/yr. On the other hand, upland area has increased 22.5 $km^2$. Soil loss of upland has increased 5395.4 to/yr. Therefore, soil loss in 2000 increased 6.3 kg/$m^2$/yr compared with that in 1990. This was mainly caused by the increased upland area.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.3
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• pp.59-67
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• 2007

This paper proposes potentialities of constructing the information system for earthquake hazard management which can manage and analyse earthquake risk and hazard systematically. The experimental results as well as architectural structure investment data for seismicity assessment are built in database and connected with GIS for assessing earthquake safety of building in urban area. For earthquake-resistant performance assessment, we collected and classified building structural data according to assessment criteria using building register, architectural map, digital map, and then complemented database with field survey data. We also suggest GIS-based information system can cope with and manage earthquake hazard effectively, as evaluating earthquake risk by performing detailed earthquake-resistant assessment and determining final assessment scores. The assessment should be processed quickly and accurately by integrating the earthquake hazard information management system with modularization of assessment procedure and method in the future.