• Spatial Information Research
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• v.10 no.2
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• pp.215-232
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• 2002

Variables representing neighborhood quality should be included in hedonic price models to control lfor the influences of negative or positive externalities from the quality of neighborhood on urban housing prices. This study proposes a GIS-based method to effectively measure the neighborhood quality variable when data on the neighborhood quality are aggregated by census sub area. This study also tests the superiority of the proposed neighborhood quality variable created by intensive use of GIS operations to a neighborhood variable not based on GIS operations in explaining the housing price variations by using Seoul＇s apartment sales data. The results from this study show that the neighborhood quality variable based on GIS-based operations shows better performance in explaining the urban housing price variations in Seoul＇s housing market. The implication from the results is that the potentials of GIS-based spatial operations in creating neighborhood quality variables should be well acknowledged by the researchers in the area of urban housing market study and GIS-based spatial operations should be more actively applied to generate better neighborhood quality variables for hedonic price models.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.4 no.1
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• pp.43-48
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• 1986

To improve the accuracy of the interpolation point of the digital terrain models, this paper compared the methods of terrain data acquisition and the equations of the curved surface

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.278-278
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• 2022

2020년 집중호우로 인하여 우리나라 전국에 걸쳐 약 2,000여 곳의 산사태, 토석류가 발생하였고 약 1,217ha의 피해 면적이 발생하였다. 피해지역의 특히 생활권 중심의 사면과 계류의 관리 필요성이 높아지고 있다. 산림청 산사태정보시스템에서는 토양함수지수가 80% 도달 시 주의보, 100% 도달 시 경보를 발령하는 대국민 서비스를 제공하고 있다. 본 연구에서는 토층의 깊이에 따른 함수비 분포에 따라 토석류의 발생 가능성에 대한 분석을 수행하고자 하였으며, 토양함수는 기상 수치모델에 의한 예측 강우 자료를 활용하였다. 예측 강우 모델은 토석류가 주로 발생하는 여름철 집중호우 시기인 남서풍을 고려하여 도메인을 구성하였고 산림의 증발산 및 토양수분 모의 정확도 향상을 위해 임상도와 토지피복도를 사용하여 보정하였다. 토층내 토양수분의 함량은 토질에 따라 그 특성이 다르기 때문에 토질과 관련한 주제를 이용하여 토양정보를 활용하였다. 내부마찰각, 점착력, 단위중량, 밀도, 지질도, 지형경사, 표고, 유효토심에 대한 정보를 구축하여, 예측강우에 따라 토층의 수분 함량을 추정하여 붕괴 발생 가능성을 분석하였다. 2006년 평창지역에서 발생한 토석류에 대하여 수행하였으며 토층의 심도는 0.5~1m 범위의 분포에 대하여 체적함수에 따른 실제 토석류 발생에 대한 검증을 수행하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.1
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• pp.159-166
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• 1992

Landsat data are valuable in itself, and if they are classified in quantitative information and transformed to practical users, they will be more useful. In this view, it is very important to extract hydrologic parameter from Landsat data and to develope the hydrologic model that can be transformed to hydrologist to use it. This study is primary step for accomplishment of such purpose. This paper include output of hydrologic model which define the relation between soil condition and discharge and process of analysis of optical image or digital image that is adapted for hydrologic model. Finally, this paper present that Landsat image is very useful, economic and produce sufficiently accurate information for hydrologic model in large area watershed.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.103-103
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• 2012

본 연구에서는 시험포장($1276.6m^2$)에서의 지표피복 BMPs (Best Management Practices) 시나리오를 적용하여 얻은 평균 유출저감율을 HSPF 모델에 적용하여 유역차원에서의 비점원오염 저감효과를 평가하고자 한다. 본 연구에서는 별미천 유역($1.21km^2$)을 대상으로 모형의 적용을 위한 입력자료로 기상자료와 지형자료를 구축하였으며 기상자료로 수원, 양평, 이천 기상관측소 자료를 구축하였으며, 지형자료로 격자크기 2m의 DEM (Digital Elevation Model)과 토지이용도는 2006년 5월 1일 QuickBird 영상을 제공받아 기존 환경부, 건교부, USGS의 토지피복분류체계 및 현장조사를 통하여 QuickBird 영상으로부터 추출 가능한 정밀농업정보에 대한 항목을 결정하였으며, 정사보정된 QuickBird 영상을 스크린 디지타이징 기법(On-Screen Digitizing Method)을 이용하여 총 21개 토지이용항목의 정밀토지이용도를 구축하였다. 실제모니터링으로 측정된 자료를 바탕으로 수위-유량곡선 산정 및 오염부하곡선을 선정, 2011년 6월 8일부터 10월 31일 분석기간으로 HSPF 모델링을 실시하였으며 모의결과 월별 통계에 따른 적용성 분석으로 RMSE (Root Mean Square Error) 는 1.15 ~ 1.76(mm/day), $R^2$는 0.62 ~ 0.78, Nash-Sutcliffe model efficiency (NSE)는 0.62 ~ 0.76로 모의치는 실측치와 유의성이 있는 것으로 분석되었다. 또한, Sediment, T-N, T-P의 $R^2$는 각각 0.72, 0.62, 0.63으로 상관성을 보이는 것으로 분석되었다. 시험포장으로부터 얻어진 event별 볏짚을 이용한 지표피복시나리오적용 후 밭에서의 평균 유출 약 10 % 유출율 감소 조건과 실제 평균 비점원오염 저감효과 89.7 % ~ 99.4 %의 결과로부터 지표피복효과의 침투효과를 HSPF 모델로 적용하기 위해 침투량(INFILT)를 조절하여 평균유출 약 10 %가 감소되는 16.0 mm/hr 값을 선정하였다. 그 결과, Sediment. T-N, T-P의 평균 저감율은 각각 87.2 %, 28.5 %, 85.1 %로 나타났으며 이는 시험포장에서의 실제 평균 비점오염 저감효과 89.7 % ~ 99.4 %에 근접함을 알 수 있었다. 이 결과로부터 침투량 조절에 따른 지표피복(침투짚단)효과는 Sediment, T-P에서 저감효율이 80 % 이상으로 높았지만 T-N은 약 30 %로 낮은 저감율을 보임으로써 저감효과가 크지 않음을 나타냈다.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1035-1046
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• 2022

This study evaluated the applicability of multi-resolution data fusion for land-cover classification. In the applicability evaluation, a spatial time-series geostatistical deconvolution/fusion model (STGDFM) was applied as a multi-resolution data fusion model. The study area was selected as some agricultural lands in Iowa State, United States. As input data for multi-resolution data fusion, Moderate Resolution Imaging Spectroradiometer (MODIS) and Landsat satellite images were used considering the landscape of study area. Based on this, synthetic Landsat images were generated at the missing date of Landsat images by applying STGDFM. Then, land-cover classification was performed using both the acquired Landsat images and the STGDFM fusion results as input data. In particular, to evaluate the applicability of multi-resolution data fusion, two classification results using only Landsat images and using both Landsat images and fusion results were compared and evaluated. As a result, in the classification result using only Landsat images, the mixed patterns were prominent in the corn and soybean cultivation areas, which are the main land-cover type in study area. In addition, the mixed patterns between land-cover types of vegetation such as hay and grain areas and grass areas were presented to be large. On the other hand, in the classification result using both Landsat images and fusion results, these mixed patterns between land-cover types of vegetation as well as corn and soybean were greatly alleviated. Due to this, the classification accuracy was improved by about 20%p in the classification result using both Landsat images and fusion results. It was considered that the missing of the Landsat images could be compensated for by reflecting the time-series spectral information of the MODIS images in the fusion results through STGDFM. This study confirmed that multi-resolution data fusion can be effectively applied to land-cover classification.

• Land and Housing Review
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• v.7 no.1
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• pp.9-18
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• 2016

This research aims to build a total information system that systematizes existing sporadic information, which may lead to revitalization and efficiency of overseas urban development. To achieve this, this study firstly analyses the current information systems for urban development in foreign countries and information from the private sector. The results show that the information system that operates in the domestic agencies, are less likely to involve the contents related to information sharing, social network building and business process. However, that used in agencies ordering the overseas urban development projects, mostly provides the information of professionals, project participants and their business. Second, this research selects the information to be provided by the integrated information system and proposes a data collection plan. The information, required to push forward urban development in abroad, is classified into seven categories. Third, this study establishes a target model of comprehensive information system and makes suggestions for institutional improvement. For doing this, it categorizes overseas urban development information, links to classified information, organizes the system into three stages to services through informational channels, and then suggests a target model. Furthermore, it proposes institutional improvement to achieve efficiency of information systems through a comprehensive review of the similar cases such as administrative system of architecture(Seumter) and land information system.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.86-96
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• 2006

Ecoclimap-1, a new complete surface parameter global database at a 1-km resolution, was previously presented. It is intended to be used to initialize the soil-vegetation- atmosphere transfer schemes in meteorological and climate models. Surface parameters in the Ecoclimap-1 database are provided in the form of a per-class value by an ecoclimatic base map from a simple merging of land cover and climate maps. The principal objective of this ecoclimatic map is to consider intra-class variability of life cycle that the usual land cover map cannot describe. Although the ecoclimatic map considering land cover and climate is used, the intra-class variability was still too high inside some classes. In this study, a new strategy is defined; the idea is to use the information contained in S10 NDVI SPOT/VEGETATION profiles to split a land cover into more homogeneous sub-classes. This utilizes an intra-class unsupervised sub-clustering methodology instead of simple merging. This study was performed to provide a new ecolimatic map over Northeast Asia in the framework of Ecoclimap-2 global database construction for surface parameters. We used the University of Maryland's 1km Global Land Cover Database (UMD) and a climate map to determine the initial number of clusters for intra-class sub-clustering. An unsupervised classification process using six years of NDVI profiles allows the discrimination of different behavior for each land cover class. We checked the spatial coherence of the classes and, if necessary, carried out an aggregation step of the clusters having a similar NDVI time series profile. From the mapping system, 29 ecosystems resulted for the study area. In terms of climate-related studies, this new ecosystem map may be useful as a base map to construct an Ecoclimap-2 database and to improve the surface climatology quality in the climate model.

• Spatial Information Research
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• v.22 no.4
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• pp.59-65
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• 2014

Recently, increasing demand for 'Digital Elevation Model(DEM)' to climate change research and various development by global warming in the Arctic region. So we need to verify the accuracy to utilize DEM. In this research, we verified 'ASTER GDEM' and 'GIMP DEM' in several DEM which constructed in the Greenland that most of the area is covered ice sheet. We divided greenland into two part, ice sheet area and non ice sheet area by using the ESA globcover. Then, comparing a difference between 'ASTER DEM', 'GIMP DEM' and ICESat elevation data to verify the accuracy. As a result, GIMP DEM has higher accuracy in ice sheet area and ASTER GDEM has higher accuracy in non-ice sheet area.

• Land and Housing Review
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• v.13 no.3
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• pp.57-68
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• 2022

This study investigates what influences the 2030 households' intention to utilize housing support policies for the younger generation. Using the logistic regression model, our empirical results show that the 'the recognition of youth housing support projects', 'the housing occupation', 'employment type', 'housing type', and 'age' factors have a significant effect on the intention to use the housing support policies. Specifically, the intention is positively associated with economic activity, one-room residence, monthly rent, employment status during the Covid-19 period, and policy recognition, while negatively related to age. In addition, willingness to use the housing support policies is greater when respondents lived in a studio, lived on a monthly rent, recognized the policy, and improved their employment status. The results suggest that housing support programs need to be expanded and improved. Moreover, information on housing support policies should be efficiently delivered to eligible households, and more sophisticated housing support policies should be provided for young people early in their careers.