• Spatial Information Research
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• v.6 no.1
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• pp.11-23
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• 1998

Map generalization functions to visualize the spatial data or to change their scale by changing the level of details of data. Until recently, the studies on map generalization have concentrated more on line features than on point features. However, point features are one of the essential components of digital maps and cannnot be ignored because of the great amount of information they carry. This study, therefore, aimed to find out a detailed procedure of point features' generalization. Particularly, this work chose the distribution pattern of point features as the most important factor in the point generalization in investigating the geometric characteristics of source data. First, it attempted to find out the characteristics of distribution pattern of point features through quadrat analysis with Grieg-Smith method and nearest-neighbour analysis. It then generalized point features through the generalization threshold which did not alter the characteristics of distribution pattern and the removal of redudant point feautres. Therefore, the generalization procedure of point features provided by this work maintained the geometric characteristics as much as possible.

• Journal of Cadastre & Land InformatiX
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• v.47 no.2
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• pp.19-37
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• 2017

Visible Infrared Imaging Radiometer Suite Day-Night Band (VIIRS-DNB) data provides a much higher capability for observing and quantifying nighttime light (NTL) brightness in comparison with Defense Meteorological Satellite-Operational Linescan System (DMSP-OLS) data. In South Korea, there is little research on the detection of NTL brightness change using VIIRS-DNB data. This study analyzed the spatial distribution and change of NTL brightness between 2013 and 2016 using VIIRS-DNB data, and detected its spatial relation with possible influencing factors using regression models. The intra-year seasonality of NTL brightness in 2016 was also studied by analyzing the deviation and change clusters, as well as the influencing factors. Results are as follows: 1) The higher value of NTL brightness in 2013 and 2016 is concentrated in Seoul and its surrounding cities, which positively correlated with population density and residential areas, economic land use, and other factors; 2) There is a decreasing trend of NTL brightness from 2013 to 2016, which is obvious in Seoul, with the change of population density and area of industrial buildings as the main influencing factors; 3) Areas in Seoul, and some surrounding areas have high deviation of the intra-year NTL brightness, and 71% of the total areas have their highest NTL brightness in January, February, October, November and December; and 4) Change of NTL brightness between summer and winter demonstrated a significantly positive relation with snow cover area change, and a slightly and significantly negative relation with albedo change.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.2
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• pp.85-92
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• 2013

This study determined the spatial distribution characteristics of carbon dioxide in Northeast Asia, connecting land coverage and vegetation index that have influence on concentration and distribution of carbon dioxide measured by GOSAT with GIS spatial analysis method. The results visibly showed that the spatial distribution of carbon dioxide had different patterns in dependent on the present status of land use in its surrounding area. Such high concentration of carbon dioxide was formed in developed sites like cities while forest areas showed low concentration of it. We also found that there were relatively high negative(-) correlations between carbon dioxide and vegetation, in statistically significant level. It is expected to be used as a basic data for establishing measures to reduce greenhouse gas in the future.

• Journal of the Korean association of regional geographers
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• v.23 no.1
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• pp.118-135
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• 2017

The decline in urban center, changes in the population structure, economic slump and etc. have caused empty or deserted houses in the city. The government recognizes the houses as the reason for the accelerated formation of local slum, and as the negative element threatening the residential environment, urban landscape, social stability and others. This research aims at investigating the spatial distribution of empty or deserted houses in Gwangju metro city, identifying hotspots and classifying those hotspot according to the socioeconomic indicators as well as physical ones, and examining their characteristics and problems in the urban space. The results of this study are as follows. First of all, there is a positive spatial autocorrelation in the spatial distribution of empty and deserted houses in Gwangju metro city. Second, several hotspots are identified mainly around the old CBD area showing a sign of urban decline. Third, the indicators of urban decline were visualized using triangulation charts, and hotspots of empty(deserted) houses are classified so that the classification could serve for effective urban regeneration policy making tailored for each region.

• Journal of Cadastre & Land InformatiX
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• v.47 no.1
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• pp.27-35
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• 2017

Human activity such as agriculture, industrial development and urban sprawl has been the major threat to wetlands ecosystem, which have caused the greatest losses of coastal wetlands. The Garorim bay provides one of the most important wetland habitate and Ministry of Oceans and Fisheries designated Garorim bay to marine ecosystem protected area in July 2016. The purpose of this research is to analysis the spatial pattern of Garorim bay using Landsat 5 (TM), Landsat 7 (ETM+), Landsat 8 (OLI & TIRS). The surface temperature and NDVI of Garorim bay were processed with spatial analysis method and time series analysis were applied to 25 years Landsat satellite 19 images. The results of time series distribution map compared with the several wetland habitate on remotely sensed images. Landsat images showed the change area of wetland vegetation distribution from 1988 to 2014. The southern part habitate of Garorim bay have been changed with vegetation patterns on coastal wetland which were covered with tidal flat.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.4
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• pp.162-174
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• 2012

To visualize the characteristics of vertical seawater temperature data, in the ocean having 3D spatial characteristics, 2D thematic maps like horizontal seawater temperature distribution map at each depth layer and 3D volume model using 3D spatial interpolation are used. Although these methods are useful to understand oceanographic phenomena visually, there is a limit to analyze the spatial pattern of vertical temperature distribution or the relationship between vertical temperature characteristics and other oceanic factors (seawater chemistry, marine organism, climate change, etc). Therefore, this study aims to determine the spatial distribution characteristics of vertical temperature profiles in the South Sea of Jeju by quantifying the characteristics of vertical temperature profiles by using an algorithm that can extract the thermocline parameters, such as mixed layer depth, maximum temperature gradient and thermocline thickness. For this purpose spatial autocorrelation index (Moran's I) was calculated including mapping of spatial distribution for three parameters representing the vertical temperature profiles. Also, after grouping study area as four regions by using cluster analysis with three parameters, the characteristics of vertical temperature profiles were defined for each region.

• Spatial Information Research
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• v.8 no.2
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• pp.213-232
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• 2000

It is important to scrutinize spatial patterns in crime analysis since crime data has geographical attribute in itself. We focus on the development of ¨Crime Analysis GIS¨ prototype which can discover spatial patterns in crime data by integrating mapping functions of GIS and spatial analysis techniques. The structure of this system involves integration of DBMS and GIS, and the major functions of the system include (i) exploring spatial distribution of point data, (ii) mapping hot-spot, (iii) clustering analysis of crime occurrence, and (iv) analyzing aggregated areal data. The process of design and implementation of this system is based on object-oriented methodologies. A web-based extension of the prototype using 3-tier architecture is currently under development.

• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.414-432
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• 2012

Land price is a kind of text to read urban spatial structure. The purpose of this paper is to inquire into the characteristics of Daegu's urban structure and its change in time through exploring spatio-temporal variations of land price with a detailed spatial and temporal resolution. To achieve this, land value surfaces were represented using the officially assessed land price every other year from 1995 to 2011. Through mapping and exploring spatio-temporal patterns and fluctuation rates of land price for this period, changes in urban structure, the effects of local decision makings such as Greenbelt adjustment, housing site development, and gentrification, and the effects of business fluctuations or policies at global or national scales could be caught. In addition, the trends for suburbanization and multi-centric urban form could be examined from the results of a negative exponential model explaining the effect of distance from an urban center on spatial variation of land price. These results demonstrate that urban analysis using land price mirroring spatial decision making at various scales could deepen understanding for internal structure and change of a city and provide useful information for establishing regional and urban development policies and evaluating their effects.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.4
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• pp.100-118
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• 2015

This study established a land-cover classification method on objects using satellite images, and figured out distributional patterns of land cover according to categories through spatial statistics techniques. Object-based classification generated each land cover classification map by spectral information, texture information, and the combination of the two. Through assessment of accuracy, we selected optimum land cover classification map. Also, to figure out spatial distribution pattern of land cover according to categories, we analyzed hot spots and quantified them. Optimal weight for an object-based classification has been selected as the Scale 52, Shape 0.4, Color 0.6, Compactness 0.5, Smoothness 0.5. In case of using the combination of spectral information and texture information, the land cover classification map showed the best overall classification accuracy. Particularly in case of dry fields, protected cultivation, and bare lands, the accuracy has increased about 12 percent more than when we used only spectral information. Forest, paddy fields, transportation facilities, grasslands, dry fields, bare lands, buildings, water and protected cultivation in order of the higher area ratio of DMZ according to categories. Particularly, dry field sand transportation facilities in Yanggu occurred mainly in north areas of the civilian control line. dry fields in Cheorwon, forest and transportation facilities in Inje fulfilled actively in south areas of the civilian control line. In case of distributional patterns according to categories, hot spot of paddy fields, dry fields and protected cultivation, which is related to agriculture, was distributed intensively in plains of Yanggu and in basin areas of Cheorwon. Hot spot areas of bare lands, waters, buildings and roads have similar distribution patterns with hot spot areas related to agriculture, while hot spot areas of bare lands, water, buildings and roads have different distributional patterns with hot spot areas of forest and grasslands.

• Journal of Korean Society for Geospatial Information Science
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• v.6 no.1 s.11
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• pp.105-116
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• 1998

The spreading of hot waste water discharged from the coastal power station is a new problem to marin e circumstances and the fishery. Because the survey of hot waste water discharges should be performed is multaneously across wide areas, it is very difficult. Some sensors of the Landsat can draw the spread and distribution of water temperature from wavelength range of thermal infrared. The present study applied the GIS after stretching DN for the purpose of drawing a more accurate distribution of water temperature. Accordingly, the pattern of water temperature distribution could be expressed more precisely for a broad area, and the spread and distribution of hot waste water could be analyzed economically.