• Title/Summary/Keyword: satellite Imagery

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Analysis of Rainfall-Runoff Characteristics on Impervious Cover Changes using SWMM in an Urbanized Watershed (SWMM을 이용한 도시화유역 불투수율 변화에 따른 강우유출특성 분석)

  • Oh, Dong Geun;Chung, Se Woong;Ryu, In Gu;Kang, Moon Seong
    • Journal of Korean Society on Water Environment
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    • v.26 no.1
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    • pp.61-70
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    • 2010
  • The increase of impervious cover (IC) in a watershed is known as an important factor causing alteration of water cycle, deterioration of water quality and biological communities of urban streams. The study objective was to assess the impact of IC changes on the surface runoff characteristics of Kap Stream basin located in Geum river basin (Korea) using the Storm Water Management Model (SWMM). SWMM was calibrated and verified using the flow data observed at outlet of the watershed with 8 days interval in 2007 and 2008. According to the analysis of Landsat satellite imagery data every 5 years from 1975 to 2000, the IC of the watershed has linearly increased from 4.9% to 10.5% during last 25 years. The validated model was applied to simulate the runoff flow rates from the watershed with different IC rates every five years using the climate forcing data of 2007 and 2008. The simulation results indicated that the increase of IC area in the watershed has resulted in the increase of peak runoff and reduction of travel time during flood events. The flood flow ($Q_{95}$) and normal flow ($Q_{180}$) rates of Kap Stream increased with the IC rate. However, the low flow ($Q_{275}$) and drought flow ($Q_{355}$) rates showed no significant difference. Thus the subsurface flow simulation algorithm of the model needs to be revisited for better assessment of the impact of impervious cover on the long-term runoff process.

4S Framework Construction Structure for Interoperability of Spatial Information (공간 정보의 상호운용성을 위한 4S 기반 프레임워크 구축)

  • Oh, Byoung-Woo;Kim, Min-Soo;Joo, In-Hak;Lee, Jong-Hun;Yang, Young-Kyu
    • Journal of Korea Spatial Information System Society
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    • v.3 no.1 s.5
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    • pp.95-108
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    • 2001
  • The provision of spatial data is a key infrastructural requirement for the promotion of economic growth, environmental quality, social progress, etc. 4S technology integrates 4 kinds of systems that process spatial data: GIS (Geographic Information System), GNSS (Global Navigation Satellite System), ITS (Intelligent Transport System), and SIIS (Spatial Imagery Information System). Spatial data processing field is expected to get synergy effect and overcomes development limit of individual unit technology via 4S technology. This paper discusses both the development of 4S-kernel technology and the construction of 4S-based framework, In the development of 4S kernel technology, we will concentrate on the following issues: the development of 4S base components for reciprocity integration among GIS, SIIS, GNSS and ITS technologies, the development of 4S-Mobile S/W and H/W, 4S-Van components, and national LBS technologies. And in the construction of 4S-based framework, we will especially concentrate on the ISP for overall 4S technologies, the international cooperative research center, and the guide model deduction for supervision and certification of 4S projects. Finally, we examine about how the construction of 4S-baed framework affects 4S industry.

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Feasibility on Generating Topographic Map Using KOMPSAT (다목적 실용위성(KOMPSAT)을 이용한 지형도 제작의 가능성 분석)

  • 조우석
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.16 no.2
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    • pp.281-289
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    • 1998
  • Korea is developing a Korea Multi-Purpose Satellite I (KOMPSAT-1) as one of Korea National Space Program, which will be launched in 1999. The EOC (Electro-Optical Camera) is the primary payload for KOMP-SAT-1. The main mission of EOC is to provide the images for the production of scale maps of Korean territory. This research is focused on methodology and possibility for the production of topographic maps using EOC sensor. Since the imagery from EOC is not yet available, SPOT Level 1A image data which are quite similar to those of EOC, and Intergraph Imagestation (Digital Photogrammetric Workstation) are implemented in the process of sample digital map generation. The sample digital maps generated from SPOT stereoimages were compared and analyzed with the existing 1:50,000 scale digital map produced by National Geography Institute. The feasibility and problem encountered in 1:50,000 scale digital mapping using SPOT stereoimages were presented. Based on results, the feasibility and further research areas for KOMPSAT-EOC in the line of 1:25,000 and 1;50,000 digital mapping were discussed.

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3D Object Simplification for Google Earth Uploading of the Cultural Resources and Tourist Attractions (문화.관광 자원의 구글어스 Uploading을 위한 3D 객체 단순화)

  • Youn, Jae-Hong;Choi, Hyo-Seung;Jeong, Seung-Moon
    • Journal of Korean Society for Geospatial Information Science
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    • v.17 no.4
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    • pp.45-51
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    • 2009
  • Different countries around the world, using their traditional culture as a background, are promoting new changes and reformation in development and publicity method of cultural contents to promote national interests and to increase their competitiveness. Also, as the citizen's standard of living and quality of living goes up, various demands for the enjoyment of traditional culture goes up accordingly as well. As the cultural assets environment become more complicated and diverse, there is a need for systematic management and preservation plan. Keeping these viewpoints in mind, the geo-spatial information provision service using the web provides various forms of services such as satellite imagery, terrain, and 3D viewing, enabling the user to gain concrete spatial information on specific areas. The geo-spatial information using 3D modeling is done only in limited spaces because of construction expenses or difficulties in management and maintenance. In this thesis, I would like to propose Effective method for the GoogleEarth Uploading through simplification of 3D object for the publicity of traditional buildings and Cultural Resources and Tourist Attractions.

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Measuring Water Depth by Using a Combination of GPS/Echosounder (음향측심기와 위성항법을 이용한 하천의 수심 측량)

  • 정영동;강상구
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.20 no.4
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    • pp.375-381
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    • 2002
  • Depth of water information is obtained mainly from echo-sounding instrument which observes the round-trip time of signal from water surface to the bottom. Photogrammetry, underwater survey and laser survey etc. are also used as another method of bathymetric surveying. These methods are used specially for making track chart in a shallow water area. On the other hand, aircraft or satellite imagery ara also used in the sea area where the effect of suspended material is low and water quality is good. Presently, general bathymetric surveying has been performed in our country, but the spatial density of surveyed point are relatively low. Therefore, in this study we built a grid water depth chart which measured combing echosounder with GPS-RTK method and the depth accuracy was analyzed by using the data of direct survey water depth. As a results, the bathymatric mapping which use echosounder is more economical method compared to the existing methods.

Image Mosaic using Multiresolution Wavelet Analysis (다해상도 웨이블렛 분석 기법을 이용한 영상 모자이크)

  • Yang, In-Tae;Oh, Myung-Jin;Lee, In-Yeub
    • Journal of Korean Society for Geospatial Information Science
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    • v.12 no.2 s.29
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    • pp.61-66
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    • 2004
  • By the advent of the high-resolution Satellite imagery, there are increasing needs in image mosaicking technology which can be applied to various application fields such as GIS(Geographic Information system). To mosaic images, various methods such as image matching and histogram modification are needed. In this study, automated image mosaicking is performed using image matching method based on the multi-resolution wavelet analysis(MWA). Specifically, both area based and feature based matching method are embedded in the multi-resolution wavelet analysis to construct seam line.; seam points are extracted then polygon clipping method are applied to define overlapped area of two adjoining images. Before mosaicking, radiometric correction is proceeded by using histogram matching method. As a result, mosaicking area is automatically extracted by using polygon clipping method. Also, seamless image is acquired using multi-resolution wavelet analysis.

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Patterns of Strong Heat Waves within the Seoul Metropolitan Area and Its Impacts on Elderly Mortality Based on the Last 100 Year Observations (지난 100년 동안 서울시에 발생한 강한 열파 패턴과 노인사망자에 미치는 영향)

  • Choi, Gwang-Yong
    • Journal of the Korean Geographical Society
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    • v.45 no.5
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    • pp.573-591
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    • 2010
  • In this study, trends of heat waves in the populous Seoul metropolitan area over the last 100 years (1908-2007) and spatio-temporal patterns of extreme heat waves and excessive human mortality are examined. In spite of recent global warming, there is no observable increasing or decreasing pattern in the frequency and intensity of heat waves in Seoul due to increases of summer precipitation. Among numerous episodes over the last 100 years in Seoul, 1994 summer is recognized as the unprecedented, most extreme hot episode with long-lasting, intense heat waves Meteorological data observed at the Automatic Weather Stations (AWS) and land surface temperature data derived from Landsat TM satellite imagery in July 1994 reveal that extreme heat waves cause more abnormal increase of elderly mortality in the urbanized areas than in the surroundings covered with more vegetation. This study provides bioclimatological evidences of why urban thermal environments should be seriously considered in the future urban revitalization planning.

Automatic Measuring of GCP's Image Coordinates using Control Point Patch and Auxiliary Points Matching (기준점 패치 및 보조점 정합에 의한 지상기준점의 영상좌표 자동관측)

  • Kang, Myung-Ho;Bang, Soo-Nam;Lee, Yong-Woong
    • Journal of Korean Society for Geospatial Information Science
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    • v.11 no.2 s.25
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    • pp.29-37
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    • 2003
  • An approach is described for automatic measuring of GCP's image coordinates from SPOT imagery and focused on the fulfillment an automatic orientation of satellite images. For the orientation of a stereopair of digital images, firstly, GCP(Ground Control Point) should be selected and then the work for measuring of image coordinates correspond to GCPs is required. In this study, we propose the method for extracting the GCP's image coordinates automatically using an image patch for control points and auxiliary points matching. For the evaluation of measurement accuracy, a comparison between points those are extracted manually and automatically by a proposed method have made. Finally, we shows the feasibility of automatic image coordinates measurment by applying in stereo modeling for SPOT images.

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Modeling of Emissions from Open Biomass Burning in Asia Using the BlueSky Framework

  • Choi, Ki-Chul;Woo, Jung-Hun;Kim, Hyeon Kook;Choi, Jieun;Eum, Jeong-Hee;Baek, Bok H.
    • Asian Journal of Atmospheric Environment
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    • v.7 no.1
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    • pp.25-37
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    • 2013
  • Open biomass burning (excluding biofuels) is an important contributor to air pollution in the Asian region. Estimation of emissions from fires, however, has been problematic, primarily because of uncertainty in the size and location of sources and in their temporal and spatial variability. Hence, more comprehensive tools to estimate wildfire emissions and that can characterize their temporal and spatial variability are needed. Furthermore, an emission processing system that can generate speciated, gridded, and temporally allocated emissions is needed to support air-quality modeling studies over Asia. For these reasons, a biomass-burning emissions modeling system based on satellite imagery was developed to better account for the spatial and temporal distributions of emissions. The BlueSky Framework, which was developed by the USDA Forest Service and US EPA, was used to develop the Asian biomass-burning emissions modeling system. The sub-models used for this study were the Fuel Characteristic Classification System (FCCS), CONSUME, and the Emissions Production Model (EPM). Our domain covers not only Asia but also Siberia and part of central Asia to assess the large boreal fires in the region. The MODIS fire products and vegetation map were used in this study. Using the developed modeling system, biomass-burning emissions were estimated during April and July 2008, and the results were compared with previous studies. Our results show good to fair agreement with those of GFEDv3 for most regions, ranging from 9.7 % in East Asia to 52% in Siberia. The SMOKE modeling system was combined with this system to generate three-dimensional model-ready emissions employing the fire-plume rise algorithm. This study suggests a practicable and maintainable methodology for supporting Asian air-quality modeling studies and to help understand the impact of air-pollutant emissions on Asian air quality.

A Case Study on Suitability Analysis of Solid Waste Landfill Site utilizing GIS (GIS를 활용한 폐기물 매립지의 적지분석 사례연구)

  • Lee, Jin-Duk;Yeon, Sang-Ho;Kim, Sung-Gil
    • Journal of the Korean Association of Geographic Information Studies
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    • v.3 no.4
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    • pp.33-49
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    • 2000
  • This research demonstrates the application of GIS to the selection of the waste landfill site through the case study of a urban area. The estimation factors for the suitability analysis of the waste landfill site were determined. The database was built through collection, input, and transformation of data. The recent land cover classification data and NDVI data which were obtained through processing of satellite imagery were incorporated into GIS data as estimation factors. The relative weights of importance among 2nd category estimation factors were determined by the pairwise comparison method. Also relative weights of 1st category estimation factors which are divided into the social-economical factor and the natural environmental factor were combined with those of 2nd category estimation factors. As the results of this case study, the suitability analysis was conducted in accordance with various estimation criteria. The highest suitability index was obtained in the case where we considered the relative weights of 2nd category estimation factors as different in the viewpoint which regards the social economical factor as important.

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