• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.215-220
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• 2004

유역수문모형에서 SCS방법 적용시 입력되는 주요 매개변수인 유역평균 CN값은 RS와 GIS를 적용하면 쉽게 계산이 가능하나, 입력자료의 종류 및 공간해상도의 선택에 따라 같은 자료일 지라도 다르게 계산된다. 본 연구에서는 Landsat 7 ETM+,SPOT 5, 1:25,000 토지이용현황도, 정밀토양도, 개략토양도를 이용하여 2.5m, 30m 공간해상토의 자료로부터 유역평균CN을 계산하였으며, 이들을 각각 2.5m～1000m 크기의 격자로 재배열하여 유역평균을 비교함으로서 해상도가 유역 CN값 변화와 어떠한 관계가 있는지 분석하고자 하였다. 분석결과 해상도에 따라 일정구간 이상에 대하여 오차를 나타내고 있었으며, 자료의 선택에 따라 유역평균 CN 값의 변화가 있는 것으로 분석되었다.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.309-313
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• 2009

산불은 전세계적으로 발생하는 가장 주요한 재해현상 중 하나이다. 산불 감시나 산불에 의한 피해지역의 효과적인 관측은 피해 지역을 최소화하고, 효율적인 피해 복구 계획 수립에 매우 중요한 기초자료를 제공한다. 광학 위성 자료를 활용한 산불 피해지역 탐지가 널리 사용되고 있음에도 불구하고, 산불에 의한 연기 또는 구름 분포에 의해 종종 사용상에 제약이 있다. 본 연구에서는 2000년 4월 강원도 고성, 강릉, 삼척, 물진 지역에서 발생한 대규모 산불을 연구 대상지역으로 하여, 1998년-2000년 동안 획득된 RADARSAT-1 SAR 영상을 이용하여 산불 피해 지역 감시의 활용성을 연구하였다. 산불에 의한 산림 피해지역 관측을 위해 RADARSAT-1 SAR 영상의 후방산란관의 변화를 통한 변환 탐지를 수행하였다. 산불 피해지역에서 산불 전에 비해 산불 후에 획득된 RADARSAT-1 SAR 영상의 후방산란값이 증가하는 것으로 관측되었다. RADARSAT-1 SAR 영상으로부터 관측된 산불 피해 지역은 Landsat-7 ETM 자료와 현장 조사 자료에 의한 산불 피해 지역과 매우 상관성이 높은 것으로 관측되었다.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.274-274
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• 2002

Damage to forest trees, caused by wildfire, changes their spectral reflectance signature. This factor led to the initiation of a research project at the Remote Sensing & GIS Laboratory, Kookmin University, to determine if multispectral data acquired by IKONOS could provide fire scar and bum severity mapping. This paper will present detail mapping of burned areas in the eastern coast of Korea with IKONOS imagery. In addition, a single post-burn Landsat-7 ETM＋ data was used to compare with IKONOS, the study area. Burn severity map based on IKONOS image was found to be affected by strong topographic illumination effects in the mountain forest. But it has better the delineation of the bum-scarred area. In this study the NDVI was analyzed for geometric illumination conditions influenced by topography(slop, aspect and elevation) and shadow(solar elevation and azimuth angle).

• Journal of the Korean Geographical Society
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• v.38 no.4
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• pp.630-639
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• 2003

This study aims to analysis the distribution and change of cropland and forest, the Onseong, Saebyeol, and Eundeok counties on the lower reach of Duman(Tumen) river, northeast Korea, using 1992 year Landsat TM data, 2000 year Landsat ETM data, and digital terrain elevation data(DTED). Land cover and land use of the study areas are classified into cropland, forest, village, and water body, using the supervised classification method including 1:50,000 DTED analysis, image band composition, and principal component analysis(PCA). Results of quantitative analysis present that each growth rate of cropland of Onseong and Eundeok are 22.8% and 14.7% corresponding to decreasing rates of forest, 8% and 13.6% during 8 years from 1992 to 2000. In Onseong, Saebyeol, and Eundeok, each values of mean elevations and slope gradients increased to 192m, 95m, and 91m from 157m, 85m, and 78m, and to 6.6$^{\circ}$, 3.0$^{\circ}$, and 4.4$^{\circ}$ from 5.2$^{\circ}$, 2.5$^{\circ}$, and 3.0$^{\circ}$. Especially, in case of newly developed cropland, the values of mean elevation and mean gradient have 225m, 122m, and 127m, and 9.4$^{\circ}$, 5.1$^{\circ}$, and 8.0$^{\circ}$, in above three regions. These new croplands were developing along to deeper valleys and toward lower hill and mountain slope up to knickpoint zone of gradient change. Deforested lands for cropland have formed irregular pattern of patch-type, and become sources for the sheet erosion, rilling and gulleying in mountain slope and sedimentation in local river channel. Though there were no field checking, analysis using landsat images and GIS mapping can help understand actual environmental problems relating to cropland development of mountain slope in North Korea.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.4
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• pp.65-77
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• 2012

This study examined changes in land cover for the past 25 years in Busan and subsequently evaluated heat island potential by using land surface temperature and observation temperature data. The results were as below. The urban area of Busan increased by more than 2.5 times for the past 25 years from 1975 to 2000. It was believed that an increase in the pavement area of city within such a short period of time was an unprecedented phenomenon unique to our country. It could be assumed that urban heat island would be worsened through this process. After analyzing the land temperature according to the land cover, it was shown that there were noticeable changes in the temperature of urban & built-up and mountain & forest areas. In particular, the temperature rose to $36{\sim}39^{\circ}C$ in industrial areas during the summer, whereas it went down to $22{\sim}24^{\circ}C$ in the urban areas at whose center there were mountains. It was found that heat island potential according to the level of land cover had various values depending on the conditions of land cover. Among the areas of urbanization, the industrial area's heat island potential is 6 to $8^{\circ}C$, and the residential and commercial area's is $0{\sim}5^{\circ}C$, so it has been found that there is high possibility to induce urban heat islands. Meanwhile, in the forest or agricultural area or the waterside, the heat island potential is $-6{\sim}-3^{\circ}C$. With this study result, it is possible to evaluate the effects of temperature increase according to the urban land use, and it can be used as foundational data to improve urban thermal environment and plan eco-friendly urban development.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.3
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• pp.101-113
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• 2015

The purpose of this study is increasing ventilation network usability for urban green space planning by enhancing its practicality and detail. A ventilation network feature extraction technique using roughness length($z_0$) was proposed. Continuously surfaced DZoMs generated from $z_0$(cadastral unit) using three interpolations(IDW, Spline, and Kriging) were compared to choose the most suitable interpolation method. Ventilation network features were extracted using the most suitable interpolation technique and studied with land cover and land surface temperature by spatial overlay comparison. Results show Kriging is most suitable for DZoM and feature extraction in comparison with IDW and Spline. Kriging based features are well fit to the land surface temperature(Landsat-7 ETM+) on summer and winter nights. Noteworthy is that the produced ventilation network appears to mitigate urban heat loads at night. The practical use of proposed ventilation network features are highly expected for urban green space planning, though strict validation and enhancement should follow. (1) $z_0$ enhancement, (2) additional ventilation network interpretation and editing, (3) linking disconnected ventilation network features, and (4) associated dataset enhancement with data integrity should technically preceded to enhance the applicability of a ventilation network for green space planning. The study domain will be expanded to the Seoul metropolitan area to apply the proposed ventilation network to green space planning practice.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.105-121
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• 2013

This study introduces integrated approach on detection of a leakage in a sea wall based on remote sensing, electric resistivity survey, electromagnetic survey, and borehole survey for the Seosan A-Region sea wall. The satellite temperature distribution from Landsat ETM+ data identifies water leakage distribution and period by analyzing temperature mixing patterns between sea water and fresh water. Electric resistivity survey provides both horizontal and vertical anomaly distributions over the sea wall showing below average electric resistivity. Electromagnetic survey(electrical conductivity survey) reveals the potential possible leakage areas with minimal background impact by comparing electrical conductivity values between high and low tides. Borehole image processing system confirmed the locations of anomalies identified from the other survey methods and distributions of vertical fracture zones. The integrated approach identified 41.7% of the sea wall being the most probable area vulnerable to water leakage and effectively approximated both horizontal and vertical distribution of water leakage. The integrated analysis of remote sensing, electric resistivity survey, electromagnetic survey and borehole survey is considered to be an optimal method in identifying water leakage distribution, period, and extent of fractures knowledged from the boreholes.

• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.7
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• pp.3-9
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• 2005

A computer system for crop information was developed using Visual Basic and ArcGIS VBA. The system is operated on ArcGIS 8.3 with Microsoft Access MDB. Landsat +ETM, KOMPSAT-1 EOC, ASTER VNIR and IKONOS panchromatic (Pan) and multi-spectral (MIS) images were included in the system to extract agricultural land use items identifiable at various spatial resolutions of images. Agriculture related data inventories using crop cover information such as texture and average pixel value of each band based on crop cultivation calendar were designed and implemented. Three IKONOS images were loaded in the system to show crop cover characteristics such as rice, pear, grape, red pepper, garlic, and surface water cover of reservoir with field surveys. GIS layers such as DEM (Digital Elevation Model), stream, road, soil, land use and administration boundary were prepared to understand the related characteristics and identify the location easily.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.760-760
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• 2012

도심 지역은 인구집중, 토지 피복의 변화 및 교통량 증가 등의 인공열 배출원의 다양화 등의 요인에 의해 주변지역보다도 기온이 높은 도시 열섬(Urban Heat Island) 현상에 의해 독특한 도시기후의 특색을 보이게 된다. 일반적으로 도시 열 환경에 대한 연구는 도시 열섬의 강도나 현상을 파악하는데 집중되어 왔다. 최근 들어 도시 열섬 현상 완화 또는 개선을 위한 관심이 높아지면서 도시내에 존재하는 수면이나 녹지를 이용한 기후개선에 대한 연구가 진행되고 있다. 하천은 다양한 생물이 서식하는 공간이면서 생물의 다양성이 풍부한 생태계의 보고로 인간과 환경이 조화를 이루어 온 공간이기도 하다. 이와 같이 하천은 지역의 다양성과 특수성에 따라 가지고 있는 기능이 다양하다. 그 중 하천의 환경 기능은 많은 열용량을 축적시켜 수면의 온도상승을 적게 하여 하천의 온도는 물론 주변지역의 온도를 낮추는 역할을 하게 된다. 특히 흐르는 물은 대류와 혼합과정을 거치며 열을 운반할 수 있으므로 효율적인 축열체가 된다. 또한 하천의 물 등은 광의 투과성이 높기 때문에 표면에서는 반사되지 않고 수체 내에 열을 저장한다. 따라서 이러한 현상이 종합적으로 작용하여 도심하천은 도심지에서 높게 형성된 온도를 낮추는 냉각효과가 있다고 판단된다. 이러한 영향을 알아보기 위해 본 연구에서는 원격탐사 기법을 이용하여 도심하천이 도시 열완경 완화에 미치는 영향을 분석하였다. 분석을 위해 2009년 9월 6일 Landsat 7 ETM+ 위성영상을 이용하여 LST (Land Surface Temperature)를 추출하고, SEBAL (Surface Energy Balance Algori- thms for Land) 모델을 이용하여 지표면 열수지 성분을 추출하였다. 그 결과, 도심하천 주변의 온도가 도심지에 비해 $2{\sim}3^{\circ}C$ 정도 낮게 형성되었으며, 잠열은 주변 도심지에 비해 하천에서 높은 분포를 나타내었다. 그러나 하천 둔치나 하천 주변의 콘크리트, 아스팔트 및 나대지 등의 토지피복은 지표면 온도가 높게 형성되어 도심의 heat spot으로 작용하여 열 환경을 악화시키나 도심하천은 cool spot 작용을 하여 도심의 열을 완화하는 기능을 갖는 것으로 판단된다.

• Asian Journal of Atmospheric Environment
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• v.6 no.2
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• pp.127-135
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• 2012

Urbanization has led to a reduction in green spaces and thus transformed the spatial pattern of urban land use. An increase in air temperature directly affects forest vegetation, phenology, and biodiversity in urban areas. In this paper, we analyze the changing land use patterns and urban heat distribution (UHD) in Seoul on the basis of a spatial assessment. It is necessary to monitor and assess the functions of green spaces in order to understand the changes in the green space. In addition, we estimated the influence of green space on urban temperature using Landsat 7 Enhanced Thematic Mapper Plus (ETM+) imagery and climatic data. Results of the assessment showed that UHD differences cause differences in temperature variation and the spatial extent of temperature reducing effects due to urban green space. The ratio of urban heat area to green space cooling area increases rapidly with increasing distance from a green space boundary. This shows that urban green space plays an important role for mitigating urban heating in central areas. This study demonstrated the importance of green space by characterizing the spatiotemporal variations in temperature associated with urban green spaces.