• Spatial Information Research
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• v.8 no.2
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• pp.243-255
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• 2000

The spatial distribution characteristics and patterns of geographic features in space can be understood through a variety of analysis techniques. The scale is one of most important factors in spatial analysis techniques. This study is aimed at identifying the characteristics of spatial data with a coarser spatial resolution and finding procedures for spatial resolution in operational scale. To achieve these objectives, this study selected LANSAT TM imagery for Sunchon Bay, a coastal wetland for a study site, applied the indices for representing scale characteristics with resolution, and compared those indices. Local variance and fractal dimension developed by previous studies were applied to measure the textual characteristics. In this study, Moran s I was applied to measure spatial pattern change of variance data which were generated from the process of coarser resolution. Drawing upon the Moran s I of variancedata was optimum technique for analysing spatial structure than those of previous studies (local variance and fractal dimension). When the variance data represents maximum Moran´s I at certainly resolution, spatial data reveals maximum change at that resolution. The optimum resolution for spatial data can be explored by applying these results.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.1
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• pp.128-141
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• 2010

Drought indices such as SPI(Standard Precipitation Index) and PDSI(Palmer Drought Severity Index) estimated using ground observations are not enough to describe detail spatial distribution of drought condition. In this study, the drought index with improved spatial resolution was estimated by using the CART algorithm and ancillary data such as MODIS NDVI, MODIS LST, land cover, rainfall, average air temperature, SPI, and PDSI data. Estimated drought index using the proposed approach for the year 2008 demonstrates better spatial information than that of traditional approaches. Results show that the availability of satellite imageries and various associated data allows us to get improved spatial drought information using a data mining technique and ancillary data and get better understanding of drought condition and prediction.

• Journal of Environmental Impact Assessment
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• v.8 no.4
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• pp.1-12
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• 1999

The purpose of this study is to develop a Water Quality Management System(WQMS), which calculates pollutant discharge and forecasts water quality with a water pollution model. Operational water quality management requires not only controlling pollutants but acquiring and managing exact information. A GIS software, ArcView 3.1 was used to enter or edit geographic data and attribute data, and Avenue Script was used to customize the user interface. PCI, a remote sensing software, was used to derive land cover classification from 20 m resolution SPOT data by image processing. WQMS has two subsystems, database subsystem and modelling subsystem. The database subsystem consisted of watershed data from digital maps, remote sensing data, government reports, census data and so on. The modelling subsystem consisted of NSPLM(NonStorm Pollutant Load Model) and SPLM(Storm Pollutant Load Model). It calculates the amount of pollutant and predicts water quality. These two subsystems were connected through a graphic display module. This system has been calibrated for and applied to Mokhyun Stream watershed.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.3
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• pp.136-145
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• 2006

SWAT includes a lot of parameters related with geography, hydrological time series, land management and water pollution, etc. So, it needs many spatial, non-spatial and time series data to run SWAT. If SWAT is operated in conjunction with GIS, we can use database which includes model input data and do all the processes which covers data creation, model input and analysis of simulation results in a system. The objective of this study is to develop HyGIS-SWAT which is the interface system to couple the SWAT model and HyGIS. To achieve this object, system operation process based on HyGIS-SWAT data model is evaluated and databases are designed and established. As a result, HyGIS-SWAT prototype system is developed. HyGIS data model and HyGIS-Model operation process can be applied effectively to the development of HyGIS-SWAT. The technologies from this study can be used as base technology to develop another HyGIS application which connect HyGIS with models.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.3
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• pp.1-12
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• 2008

This study was to develop the analyzing system for watershed characteristics data. The developed system has laid the foundation for preparing the input data in various hydrological models. The algorithms and items included in the system were derived from benchmarking of the GIS WEASEL, which used to prepare the input data of PRMS (Precipitation-Runoff Modeling System). The system was designed to develop and maintain the organized system using both object-oriented UML (Unified Modeling Language) and GIS component-based ArcObjects.

• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.1
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• pp.109-117
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• 1998

To obtain new information using a single remotely sensed image data is limited to extract various information. Recent trends in the remote sensing show that many researchers integrate and analyze many different forms of remotely sensed data, such as optical and radar satellite images, aerial photograph, airborne multispectral scanner data and land spectral scanners. Korean researchers have not been using such a combined dataset yet. This study intended to apply the technique of integration between optical data and radar data(SAR) and to examine the output that had been obtained through the technique of supervised classification using the result of integration. As a result, we found of better enhanced image classification results by using IHS conversion than by using RGB mixed and interband correlation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.12
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• pp.985-991
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• 2014

The combined method utilizing airborne LiDAR and GIS data is suggested to extract 3-dimensional hybrid city model including roads and buildings. Combining the two types of data is more efficient to estimate the elevations of various types of roads and buildings than using either LiDAR or GIS data only. This method is particularly useful to model the overlapped roads around the so called spaghetti junction. The preliminary model is constructed from the LiDAR data, which can give wrong information around the overlapped parts. And then, the erratic vertex points are detected by imposing maximum vertical grade allowable on the elevated roads. For the purpose of efficiency, the erratic vertex points are corrected through linear interpolation method. To avoid the erratic treatment of the LiDAR data on the facades of buildings 2 meter inner-buffer zone is proposed to efficiently estimate the height of a building. It is validated by the mean value(=5.26 %) of differences between estimated elevations on 2 m inner buffer zone and randomly observed building elevations.

• Spatial Information Research
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• v.15 no.3
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• pp.323-333
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• 2007

Recently, the South and North Korea have collaborated in the economic cooperation. Success for the cooperation of the South and North Korea has supported the basic and fundamental GIS data building for geographic information (GI) and the land-use of the North Korea. This North Korea GIS project is also vital to facilitate rebuilding and reconnecting socio-economic infrastructures such as reconnecting road and railway networks between the South and North Korea. Thus, this paper emphasizes on the fundamental issues of GIS data building in North Korea area and suggests GI and data establishment methods of the North Korea regions which has not been achieved in GIS research activities in Korea. As the basic GI and data in the North Korea, topographical maps, satellite imageries, and thematic maps were collected and used for surveying of territorial areas of the North Korea. The database of those dataset were built by scanning, image processing, and classifying land-use types. In addition, this paper exacted vector data from the database and included the vector data into the database as other basic GI dataset that enable to analyze quantitative and qualitative territorial land use and development in the North Korea.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.3
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• pp.19-32
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• 2002

Topographic information is indispensable in the applications that require elevational data. These applications are exemplified by watershed partition, extraction of drainage networks, viewshed analysis, derivation of geomorphologic features, quantification of landslide-terrain, and identification of topographic settings susceptible to landsliding. Therefore, we study the accuracy of data on topographic parameters derived from digital elevation models(DEMs). This research wished to analyze the effect that data source and grid size get in topography parameter using gridded DEM. An analysis of topography parameter extract and compared drainage basin, watershed slope, stream network using DEM is constructed by digital map and DTED DEM. Especially, when extract stream network from gridded DEM, received much effects according to threshold value of flowaccumulation regardless of DEM grid size. Therefore, this study applied equal threshold value of flowaccumulation for two data sources, and compare and analyzed stream network.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4228-4236
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• 2015

Due to the rapid advance in web and mobile computing technologies, normal users have become to produce, provide, and share a varied form of spatial data and information. In the domain of spatial information, numerous researches on GIS have been conducted to provide spatial information services based on a geo-sensor network and a data integration and processing technology. However, to provide user-oriented information, a context information model is necessary to associate GIS data with web and sensor data. Context awareness services is designed to provide specific information, minimizing users' interference. For which, the context information model expresses the relationship of various data from sensor networks and mobile applications and provides a user-specific information considering location and area of interest. Thus, this research aims to develops a context information model based air-pollution information system that obtains and analyses air pollution data and reflects the analysis results on an air-pollution policy. Also, this system aims to raise citizens' awareness on air-pollution and to promote citizens' participatory to improve city's air quality.