• Spatial Information Research
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• v.10 no.1
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• pp.153-164
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• 2002

This used a new method to capture the neighbouring relationship among parcels. To define the neighbouring relationship, all the surrounding parcels in the study area can be identified as neighbours of the current parcel as long as they touch each other even at a point. To examine neighbouring parcels on all polygons of the study area, this study used ArcViews avenue programming which visited each polygon in turn and produced an outfile containing the parcel record ID and the contents of each of the adjacent parcels. The second thing is to translate the record IDs of neighbouring parcels into land use. For this, this study used the Lookup function in Excel to obtain neighbouring land use. To deal with how to calculate the ratio of each land use to neighbouring land uses, this study used Visual Basic. finally, this study considered a term of neighbour land use as the ratio of the number of urban use adjacent parcels to the total number of adjacent parcels. This study shows that GIS and spatial analysis can be applied to land use change in the urban fringe area at a very detailed level using municipal parcel data which occupies about 80% of administrative affairs, especially at the local government level in Korea. The results of analysis can be useful for local government to understand its situation and to manage land use efficiently in the urban fringe. The methodology developed in this study is especially useful for an empirical approach.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.2
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• pp.3-9
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• 2013

Various data like digital maps(1/1,000 or 1/5,000), field surveying, online materials and literatures are used for the preliminary investigation for urban development such as the feasibility evaluation, the profitability analysis, the zoning proposal, the zoning designation, and the land replotting planning. There are a couple of urban development methods like an expropriation, a replotting, a mixed-used method. The replotting method requires the consideration of land replotting types based on topography and building condition, which is not easy to gather data for the preliminary investigation maintaining the security of development planning. There are limitations of a preliminary investigation using aerial photos to detect topographic and building changes at specific period. GIS data combined with high-resolution imagery has advantages over the current dataset, which come from easy acquisition of various spatial resolution satellite images, wide swath coverage, the choice of imagery resolution satisfying a usage purpose, economic benefit comparing to aerial photos, and the calculation of distance and area on imagery from image modeling. For these reasons, the proposed method in this study enables to perform the more appropriate preliminary investigation using more accurate information.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.2
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• pp.27-34
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• 2013

Due to the increased interest in global warming, interest in forest resources aimed towards reducing greenhouse gases have subsequently increased. Thus far, data related to forest resources have been obtained, through the employment of aerial photographs or satellite images, by means of plotting. However, the use of imaging data is disadvantageous; merely, due to the fact that recorded measurements such as the height of trees, in dense forest areas, lack accuracy. Within such context, the authors of this study have presented a method of data processing in which an individual tree is isolated within forested areas through the use of LIDAR data and ortho-images. Such isolation resulted in the provision of more efficient and accurate data in regards to the height of trees. As for the data processing of LIDAR, the authors have generated a normalized digital surface model to extract tree points via local maxima filtering, and have additionally, with motives to extract forest areas, applied object oriented image classifications to the processing of data using ortho-images. The final tree point was then given a figure derived from the combination of LIDAR and ortho-images results. Based from an experiment conducted in the Yongin area, the authors have analyzed the merits and demerits of methods that either employ LIDAR data or ortho-images and have thereby obtained information of individual trees within forested areas by combining the two data; thus verifying the efficiency of the above presented method.

• Journal of Environmental Impact Assessment
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• v.15 no.1
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• pp.53-65
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• 2006

Topographic condition is one of the most important things in farming activities. The topographic condition didn't matter for farming in the past because agricultural products had competitive power in the market. So farmers tried to extend their farms without any concern of topographic condition. We need less labor-consuming farming as industrial structure has been changed and the competitive power of the farming has been getting weak. This study analyzed the fallow potential in agricultural area by topographic condition so that we have got results as follows. Maps of elevation, slope, distance from roads and water resources were made for getting a fallow probability model in farms, and these 4 factors were used as independent variables while a variable on whether it is fallow or not is a dependent variable in logistic regression model. In an analysis of the fallow potential depending on farm land types, the fallow probability in fallow orchard showed the highest value of farm lands, 0.973. Cultivated orchard had 0.730 and upland had 0.616 of the fallow probability. The fields having high fallow potential had high elevation, steep slope, and long distance from water resources and roads. Especially, fields having a probability over 0.99 appeared in orchards, fallow uplands and single cropping uplands, which were recognized to have several disadvantages related to the fallow like as high elevation, steep slope, and long distance from water resources and roads. With the logistic analysis, the suitable farm lands appeared at 16.45m of the mean elevation, 1.89 degree of the mean slope, 39.91m of the average distance from water resources, and 32.39m of the average distance from roads. On the contrary, non-suitable land appeared at 114.7m of the mean elevation, 24.9 degree of the mean slope. The distance from roads was more important variable than the distance from water resources for analyzing suitable farm land.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.2
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• pp.19-29
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• 2012

Numerous studies suggested that fish assemblage structure reflects the status of stream ecosystems. The status of streams integrity, including various trophic levels, water quality and habitat degradation, can be assessed by fish assemblages. In this study, we investigated the relationships between fish assemblages and streamline geometry of streams. Previous studies suggested that geomorphologic parameter can be a critical factor of permeability between adjacent two systems. From a landscape ecological perspective, edges may partially control the flow rate of energy between two adjacent systems. Thus, the Streamline geometry can be a geomorphologic parameter that exhibits the integrity of stream. We selected the Nakdong river for study areas, which is one of major rivers and the longest (525 km) River in South Korea. We used the revised IBI representing overall ecological characteristics of Korean fish assemblages and eight sub-assessment criteria of IBI, collected from 82 sampling sites in the Nakdong River. For calculating the Streamline geometry, we measured fractal dimension index that generally used in biology, ecology and landscape ecology. We used the digital land-use/land-cover map and generated a 1-km buffer for each sampling site and refined the shape of the Streamlines. Pearson correlation analyses were performed between Streamline geometry and IBI and sub-assessment criteria of IBI. The results show that IBI and eight sub-assessments of fish are significantly correlated with geometry of Streamline. The fractal dimension of Streamline geometry were related with IBI (r = 0.48) and six sub-assessments of IBI, including total number of native fish and native species, the number of riffle benthic species, sensitive species, tolerant species and native insectivore. Especially, the number of tolerant species(r = -0.52) and native insectivore(r = 0.52) show strong correlation with geometry of Streamline. These results indicate that lower Streamline geometry can result in poor fish assemblages, while higher geometry of Streamline can enhance fish assemblages by potentially supplying insects and better habitat conditions. We expect the results of our study to be useful for stream restoration and management. However, we see the necessity of study investigating the mechanisms how Streamline geometry affect fish assemblages.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.1
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• pp.69-74
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• 2015

To analyze quantitatively environmental characteristics of cultivation area of citrus, Satsuma mandarin (Citrus unshiu Marc.), we made digital maps of environmental elements such as topography and climate. Elevation, degree of slope, and slope aspect were selected as elements of topological environment, and the annual mean air temperature, annual total precipitation, mean air temperature on January, extreme value of daily minimum air temperature, and the number of days below $-5^{\circ}C$ were selected as elements of climatic environments. The grid values of 8 environmental elements were extracted by shape of citrus farm area and analyzed distribution patterns. We can determine 3 agroclimatic criteria for growing Satsuma mandarin as over $14.5^{\circ}C$ of annual mean air temperature, over $-10.0^{\circ}C$ of extreme value of daily minimum air temperature, and less 5 days of below $-5^{\circ}C$ of daily minimum air temperature.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.12-19
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• 1999

CERES-rice, a rice growth simulation model, was used in conjunction with daily weather data to figure out the spatial variation of the phenology and yields of paddy rice at 168 rice cultivation zone units(CZU) of Kyunggi Province in 1997. Two sets of cultivar specific coefficients, which represent early and mid-season maturing varieties, were derived from field experiments conducted at two crop experiment stations. The minimum data set to run the model for each CZU (daily maximum and minimum temperature, solar irradiance, and rainfall) was obtained by spatial averaging of existing 'Digital Map of Korean Climate'(Shin et al., 1999). Soil characteristics and management information at each CZU were available from the Rural Development Administration. According to a preliminary test using 5 to 9 years field data, trends of the phasic development(heading and physiological maturity), which were obtained from the model adjusted for these coefficients, were in good agreement with the observed data. However, the simulated inter-annual variation was somewhat greater than the reported variation. Rough rice yields of the early maturing cultivar calculated by the model were comparable with the reported data in terms of both absolute value and inter -annual variation. But those of the mid season cultivar showed overestimation. After running the simulation model runs with 1997 weather data for 168 CZU's, rough rice yields of the 168 CZU's calculated by the model were aggregated into corresponding 33 counties by acreage-weighting to facilitate direct comparison with the reported statistics from the Ministry of Agriculture and Forestry. The simulation results were good at 22 out of the 26 counties with reportedly increasing yield trend with respect to the past 9 years average.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.1
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• pp.27-37
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• 2002

The classification accuracy of land cover has been considered as one of the major issues to estimate pollution loads generated from diffuse landuse patterns in a watershed. This research aimed to assess the effects of the acquisition methods and sampling size of training reference data on the classification accuracy of land cover using an imagery acquired by optical sensor(OPS) on JERS-1. Two kinds of data acquisition methods were considered to prepare training data. The first was to assign a certain land cover type to a specific pixel based on the researchers subjective discriminating capacity about current land use and the second was attributed to an aerial photograph incorporated with digital maps with GIS. Three different sizes of samples, 0.3%, 0.5%, and 1.0% of all pixels, were applied to examine the consistency of the classified land cover with the training data of corresponding pixels. Maximum likelihood scheme was applied to classify the land use patterns of JERS-1 imagery. Classification run applying an aerial photograph achieved 18 % higher consistency with the training data than the run applying the researchers subjective discriminating capacity. Regarding the sample size, it was proposed that the size of training area should be selected at least over 1% of all of the pixels in the study area in order to obtain the accuracy with 95% for JERS-1 satellite imagery on a typical small-to-medium-size urbanized area.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.1
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• pp.28-38
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• 2004

The purpose of this study is to analyze the urban hydrologic state by the use of GIS, resolution and interpolation. The determination coefficient($R^2$) and Regression Formula were derived from the contour of digital map for the accuracy, and DEM data was made by using TIN interpolation by the size of the grid. By using the observed DEM data, topographical factors were extracted from the small basin, size, the width of a basin and the slope, and were applied in the urban runoff model. Through the model, we tried to find out the most suitable runoff model in a small basin of Yosu-Munsu area. As a result of applying models to the drainage considered, the runoff hydrograph estimated by SWMM model was closer to the observed one than that estimated by ILLUDAS model. The difference between the runoff hydrograph by SWMM and the observed one is maximum error of 19%, minimum error of 5% and average error of 13%. The influence of duration in contrast to pick time is insignificant in a urban small basin. As a conclusion of this study, SWMM model was more suitable and applicable for the urban runoff model than ILLUDAS model due to its accuracy and various abilities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.287-293
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• 2018

The Korean peninsula has been known as an area that is free of volcanic disasters. However, recent observations and research results of volcanoes in Far East Asia, including Baedu Mountain and Japanese volcanoes, show that the Korean peninsula is no longer a safe area from volcanic disasters. Since 2012, the Korean government has been developing an IT-based construction technology, VDRS (Volcanic Disaster Response System), for effective volcanic disaster response system. The main users of VDRS are public officers in central or local governments. However, most of them have little experience and knowledge about volcanic disasters. Therefore, it is essential to develop education contents and implement training on volcanic disaster response for effective response in a real disaster situation. In this paper, we deal with the development of a mobile application based on virtual reality (VR) for realistic volcanic disaster response training. The objectives of training are the delivery of knowledge and experience for volcanic disasters. First, VR contents were generated based on spatial information. A 3D model was constructed based on a Digital Elevation Model (DEM), and visualization models for meterological effects and various volcanic disaster diffusion effects were implemented for the VR contents. Second, the mobile application for the volcanic disaster response training was implemented. A 12-step story board is proposed for volcanic disaster experience. The application was developed with the Unity3D engine based on the proposed story board to deliver knowledge of various volcanic disasters (volcanic ash, pyroclastic flows, volcanic mudflow etc.). The results of this paper will be used for volcanic disaster response and prevention training and for more realistic training linked with augmented reality technology in the future.