• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.12-16
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• 2009

본 연구에서는 산악형 강수의 특성을 보이는 제주도의 여러 지형 조건과 강수량의 관계를 확인하고 강수량에 영향을 미치는 주요 인자를 분석하였다. 제주도는 원추형의 형태로 중심에 한라산이 있는 전형적인 산악형 지형이고 해발고도의 분포가 $EL.0^{\sim}1950m$로 다양하여 본 연구의 대상지역으로 선정하였다. 강우자료는 제주도 내 기상관서 4개소(제주, 서귀포, 성산포, 고산) 및 자동기상관측소(AWS) 13개소의 관측자료를 활용하였으며, 짧은 자료기간을 보완하기 위해 지역빈도해석을 적용하여 확률강우량을 산정하였다. 본 연구에서는 강수에 영향을 줄 수 있는 지형인자 6개를 지리정보시스템(GIS)을 이용하여 추출하였으며, 추출된 지형인자에 대하여 요인분석으로 대표 인자를 추출하고 요인과 실제변수들의 강수량에 미치는 영향을 확인하기 위하여 회귀분석을 실시하였다. 검정결과 도출된 요인을 이용하면 강수량 산정 시 지형 변수들의 영향을 반영함과 동시에 보다 적은 수의 변수를 이용하여 지형 변수들을 모두 반영하였을 경우와 비슷한 결과를 얻는다는 것을 확인하였다. 따라서 추후 지형 변수들을 추가로 확보하여 지형특성을 반영한 간편하고 합리적인 강수량을 산정하기 위한 추가 연구가 필요할 것으로 판단된다.

• Journal of the Korean Geographical Society
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• v.33 no.3
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• pp.365-376
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• 1998

The goal of this study is to find the geomorphic variables contolling gully development on hillslopes following deforestation. Two possible geomorphic processes, surface erosion and mass movement were reviewed to compare the characteristics and geomorphic variables involved. The research objective in this paper is to find the variables and the statistical model which can explain gully density in the study area. Gully density was selected as a response variable. For log gully density, the best subset regression was found to have the variables such as area, surface length, and surface width. Log area is the most significant predictor. Even with several outliers, the normal probability plot of the residuals from this regression looks straight. So, area, surface length, and surface width explain half of the variance in gully density.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.2
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• pp.65-79
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• 2003

In this study GIS based pre- and post-processing tool for the Visual MODFLOW that is specific software to model groundwater flow is developed. This tool not only makes input data scientifically but also manages input and output data in terms of the groundwater flow analysis. In addition it can storage project products systematically into Oracle database. The most characteristic figure of this processing tool is to provide the module, which automatically or semi automatically develops various grid cell sizes using GIS ArcView and also produces DXF files reflecting various boundary conditions in the modeling zone. In particular, eminences of this research are to create 3 dimensional hydrogeological structures with 2 dimensional GIS ArcView and to conduct pre- and post- processing along with same topology and data format of the MODFLOW.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.108-120
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• 2008

This paper discusses the prediction of deforestation areas using probability models from forest census database, Geographic information system (GIS) database and the land cover database. The land cover data was analyzed using remotely-sensed (RS) data of the Landsat TM data from 1989 to 2001. Over the analysis period of 12 years, the deforestation area was about 40ha. Most of the deforestation areas were attributable to road construction and residential development activities. About 80% of the deforestation areas for residential development were found within 100m of the road network. More than 20% of the deforestation areas for forest road construction were within 100m of the road network. Geographic factors and vegetation change detection (VCD) factors were used in probability models to construct deforestation occurrence map. We examined the size effect of area partition as training area and validation area for the probability models. The Bayes model provided a better deforestation prediction rate than that of the regression model.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.4
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• pp.57-64
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• 2004

In order to decrease the area damaged by forest fires and to prevent the occurrence of forest fires, the forest fire danger rating system was developed to estimate forest fire risk by means of weather, topography, and forest type. Forest fires occurrence prediction needs to improve continually. Logistic regression and spatial analysis was used in developing the forest fire occurrence probability model. The forest fire danger index in accordance to the probability of forest fire occurrence was used in the classification of forest fire occurrence risk regions.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.2
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• pp.87-96
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• 2004

When watershed spatial database is constructed from DEM, hydrological geographic characteristics of watershed can be easily extracted. And the characteristics can be assigned and managed as the attribute of spatial database. In this study the scheme of constructing framework spatial database which is basic information for managing watershed information is examined. We established framework spatial data and defined the relationship of the data. And framework spatial database of test site was constructed. In this study, HyGIS(Hydrological Geographic Information System) which is developed by domestic technology for making hydrological spatial data and developing water resources system is used. Hydrological geographic characteristics and spatial data is extracted by HyGIS. And the data from HyGIS is used for constructing framework spatial database of test site. Finally, this study suggests the strategy of constructing framework spatial database for developing watershed management system based on river network.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.3
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• pp.26-67
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• 2020

Synthetic Aperture Radar(SAR) is able to photograph the earth's surface regardless of weather conditions, day and night. Because of its possibility to search for hydrological factors such as soil moisture and groundwater, and its importance is gradually increasing in the field of water resources. SAR began to be mounted on satellites in the 1970s, and about 15 or more satellites were launched as of 2020, which around 10 satellites will be launched within the next 5 years. Recently, various types of SAR technologies such as enhancement of observation width and resolution, multiple polarization and multiple frequencies, and diversification of observation angles were being developed and utilized. In this paper, a brief history of the SAR system, as well as studies for estimating soil moisture and hydrological components were investigated. Up to now hydrological components that can be estimated using SAR satellites include soil moisture, subsurface groundwater discharge, precipitation, snow cover area, leaf area index(LAI), and normalized difference vegetation index(NDVI) and among them, soil moisture is being studied in 17 countries in South Korea, North America, Europe, and India by using the physical model, the IEM(Integral Equation Model) and the artificial intelligence-based ANN(Artificial Neural Network). RADARSAT-1, ENVISAT, ASAR, and ERS-1/2 were the most widely used satellite, but the operation has ended, and utilization of RADARSAT-2, Sentinel-1, and SMAP, which are currently in operation, is gradually increasing. Since Korea is developing a medium-sized satellite for water resources and water disasters equipped with C-band SAR with the goal of launching in 2025, various hydrological components estimation researches using SAR are expected to be active.

• Korean Journal of Plant Resources
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• v.34 no.2
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• pp.144-155
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• 2021

This study was conducted to analyze community structure and species composition of Abies koreana forest. Field survey was carried out from June, 2019 to 2020, September. 121 plots (20×20 m) were set up, 5 herb layer plots (3×3 m) were constructed for each plot, and there, Diameter at Breast Height(DBH), height, environmental factor were measured. It was analyzed that water stress did not have a significant effect on the factors affecting the growth of A. koreana in Mt. Halla-san, and in the case of Mt. Deokyu-san, the more forest stands located at the ridge, the higher the tree density. It was found that the factors affecting the distribution of Abies koreana were not consistent according to the environment of study site.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.4
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• pp.29-38
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• 2001

This study addresses the topic of suitability analysis for helping with land use planning, which is one of important decision-making in urban planning, utilizing geographic information system. Covering the Kumi City before integrating with neighbor county, the site suitabilities for land uses, which are categorized into residential, commercial, industrial and green, were analyzed using the overlay method based upon the database constructed for this study. In the process, assessment criteria which include environmental factors and relative weights were determined and also the land use/cover map and NDVI map which were generated through satellite image processing were included in the database. The suitability maps by four function spaces were derived according to the grade and compared with the present land use state and the land use concept map of urban master plan. For more accurate analysis, practical developing plan, land price data, soil data should be included. Also if the demand estimation data by each land use had been added, the reliability of location allocation could have been raised.

• Journal of the Korean Association of Geographic Information Studies
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• v.2 no.3
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• pp.23-34
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• 1999

This study proposed the possibility of GIS to analyze stream physiographic characteristics of river basin which is important control factor in complex water management. Based on five 1:25,000 topographic maps which cover Yengchon Dam area locates upper area of Kumho River, this study analyzed the characteristics using Arc/Info(UNIX) GIS. Comparing its results and those from the existing method using digital planimeter, it could conclude as follows; First, as the results of the analysis of hypsometric curve of Yeungchon Dam area, it has the topographic characteristics of youth and maturity. And the landform of Yengchon Dam area has developed with regularity when Horton's three laws on the morphology of stream is applied. Second, the possibility of applying GIS to data management and utilization is sufficient even if it requires long time to construct topographic attribute data. Finally, a further research is needed on watershed direction with landform for the purpose of analyzing water source management and topographic property effectively.