• Title/Summary/Keyword: Snow cover

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Heavy Snowfall Disaster Response using Multiple Satellite Imagery Information (다중 위성정보를 활용한 폭설재난 대응)

  • Kim, Seong Sam;Choi, Jae Won;Goo, Sin Hoi;Park, Young Jin
    • Journal of Korean Society for Geospatial Information Science
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    • v.20 no.4
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    • pp.135-143
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    • 2012
  • Remote sensing which observes repeatedly the whole Earth and GIS-based decision-making technology have been utilized widely in disaster management such as early warning monitoring, damage investigation, emergent rescue and response, rapid recovery etc. In addition, various countermeasures of national level to collect timely satellite imagery in emergency have been considered through the operation of a satellite with onboard multiple sensors as well as the practical joint use of satellite imagery by collaboration with space agencies of the world. In order to respond heavy snowfall disaster occurred on the east coast of the Korean Peninsula in February 2011, snow-covered regions were analyzed and detected in this study through NDSI(Normalized Difference Snow Index) considering reflectance of wavelength for MODIS sensor and change detection algorithm using satellite imagery collected from International Charter. We present the application case of National Disaster Management Institute(NDMI) which supported timely decision-making through GIS spatial analysis with various spatial data and snow cover map.

The Lichen Flora of Oases of Continental Antarctic, and the Ecological Adaptations of Antarctic Lichens

  • Andreev, Mikhail
    • 한국균학회소식:학술대회논문집
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    • 2006.10a
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    • pp.24-28
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    • 2006
  • Author have studies lichen flora of the most important ice-free areas of Continental Antarctic: Bunger Hills, and the vicinity of Prudz Bay (Larsemann Hills, and Radok Lake in Prince Charles Mountains). Totally 44 lichen species from 22 genera were reported for Bunger Hills and 50 lichen species from 22 genera and 10 families: Acarosporaceae, Lecanoraceae, Lecideaceae, Parmeliaceae, Pertusariaceae, Physciaceae, Rhizocarpaceae, Stereocaulaceae, Theloschistaceae, and Umbilicariaceaewere reported for the Prudz Bay Region. 20 lichen species were found in the region for the first time. Phytogeographic analysis indicated a relatively high proportion of species with bipolar distribution - about 50% of recorded lichen species. About 30% of lichens normally don't extend into maritime zone occurring in continental Antarctic only. The most common lichen families in the region are Buelliaceae, Lecanoraceae and Teloschistaceae. The water supply and not a temperature is the critical factor for lichens in the Continental Antarctic. Moisture appears to be supplied for lichens not only from snow-melt water but mainly from air. In Maritime Antarctic, due to high air humidity macrolichens form communities everywhere (Himantormia, Usnea and Umbilicaria). In oases of Continental Antarctic extensive sites are lacking in lichen cover, even if the ground is normally snow free. Lichens occur at humid sites with moisture which were brought by winds over the ice cap and poorly developed or absent in dry areas. Of particular significance for lichens are substrate characteristics, animals influence and salinity brought by wind in coastal areas. Most rich lichen vegetation developed in oases around nests of snow petrels, where the melt water is enriched by nutrients. In contrast, the most pure vegetation is on mobile sand and gravel and in salted coastal habitats.

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Development and Performance Evaluation of an Image Detection System for Efficient 4D Images (효율적인 4D 영상을 위한 영상 검출 시스템 개발 및 성능평가)

  • Cho, Kyoung-Woo;Liu, Ze-Qi;Jeon, Min-Ho;Oh, Chang-Heon
    • Journal of Advanced Navigation Technology
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    • v.17 no.6
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    • pp.792-797
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    • 2013
  • 4D film is just a film that made by adding some physical effects to 3D film or general film. In order to provide physical effects to the audience, the data that make the physical effect must be added to each frames. In this paper, we proposed a video detection system that can efficiently provide physical effects by assessing the present situation such as explosion scene, snowing scene. The proposed video detection system contains an algorithm for fire detection by using R color and $C_r$ value, and also an algorithm for snow detection by using RGB color model. The system constitutes in a MCU that from 8051 family. In the performance evaluations, the result shows that 91% of detection rate in case of fire and 25% of false detection rate in case of snow. Also the system is capable of providing physical effects automatically.

Land-Cover Classification of Barton Peninsular around King Sejong station located in the Antarctic using KOMPSAT-2 Satellite Imagery (KOMPSAT-2 위성 영상을 이용한 남극 세종기지 주변 바톤반도의 토지피복분류)

  • Kim, Sang-Il;Kim, Hyun-Cheol;Shin, Jung-Il;Hong, Soon-Gu
    • Korean Journal of Remote Sensing
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    • v.29 no.5
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    • pp.537-544
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    • 2013
  • Baton Peninsula, where Sejong station is located, mainly covered with snow and vegetation. Because this area is sensitive to climate change, monitoring of surface variation is important to understand climate change on the polar region. Due to the inaccessibility, the remote sensing is useful to continuously monitor the area. The objectives of this research are 1) map classification of land-cover types in the Barton Peninsular around King Sejong station and 2) grasp distribution of vegetation species in classified area. A KOMPSAT-2 multispectral satellite image was used to classify land-cover types and vegetation species. We performed classification with hierarchical procedure using KOMPSAT-2 satellite image and ground reference data, and the result is evaluated for accuracy as well. As the results, vegetation and non-vegetation were clearly classified although species shown lower accuracies within vegetation class.

Study of Satellite Image Analysis Techniques to Investigate Construction Environment Analysis of Resource Development in the Arctic Circle - Alberta, Canada (북극권 자원개발 건설환경 조사를 위한 위성 영상 분석 기법 연구 - 캐나다 앨버타주 대상)

  • Kim, Sewon;Kim, YoungSeok
    • The Journal of Engineering Geology
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    • v.31 no.4
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    • pp.549-559
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    • 2021
  • The Arctic Circle's huge amounts of fossil fuels and mineral resources are being developed and subjected to active construction projects. Global efforts are continuing to actively respond to climate change, but the dependence on fossil fuels remains high. This study reports a preliminary survey conducted in Alberta, Canada, where oil sand resources are actively developed. A land cover map was prepared using satellite imagery to reduce the cost and time of surveying a wide area. Results likely useful to resource development projects such as ground surface temperature and snow cover distribution were derived by using the obtained image classification results. It is expected that the results of the present research and analysis will be used to establish strategies for the successful promotion and operation of projects to develop resources in the Arctic.

Wether Conditions for Aerial Photography (항공사진촬영을 위한 국내 기상자료 분석)

  • 조우석;이성훈;최승식;황현덕;이하준
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.04a
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    • pp.313-318
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    • 2004
  • The quality of aerial photograph is closely connected with the change of wether conditions like as cloud cover, visibility, drifted snow and so on. To solve some problems caused by wether condition, the related organizations in advanced nations have presented some standards of wether condition for aerial photography. In domestic case, the NGI has presented some standards based on the internal specification of aerial photography and the table of monthly weather condition, but it is not enough to make the quantitative and objective standards on aerial photography specification. In this paper, we proposed a method which can reflect domestic weather condition and make accurate estimation of the average number of clear days in one year for aerial photography.

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Extraction of Snow Cover Area and Depth Using NOAA/AVHRR Images (NOAA/AVHRR 위성영상을 이용한 적설분포 및 적설심 추출)

  • Kang Su Man;Lim Hyuk Jin;Kwon Hyung Joong;Kim Seong Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.948-952
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    • 2005
  • 본 연구는 우리나라 강원도 북동부 산지유역의 봄철 하천유출량에 영향을 주는 융설에 관련하여, 장기 유출 모형의 융설 모의시 융설 관련 매개변수 추정 및 정량화에 기본이 피는 적설 분포 지역 및 적설심 추출기법을 제시하였다. NOAA/AVHRR 위성영상을 이용하여 소양강 유역에 대하여 2002년 11월부터 2003년 3월까지의 적설분포를 추출한 후, 추출 결과와 유역 인근 7개 기상관측소의 최심적설심 자료와의 중첩을 통하여 적설심을 추출하였다.

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Extraction of Snowmelt Parameters using NOAA AVHRR and GIS Technique for 5 River Basins in South Korea (NOAA AVHRR 영상 및 GIS 기법을 이용한 국내 5대강 유역의 융설 매개변수 추출)

  • Shin, Hyung-Jin;Park, Geun-Ae;Kim, Seong-Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.194-198
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    • 2007
  • 융설 모형의 중요 매개변수인 적설분포면적은 실제 우리나라에서 적설과 관련한 관측 자료의 부족으로 인해 매개변수 추정이 어렵다. 이러한 문제점 해결을 위해 원격탐사기법을 활용하여 적설분포면적을 추출하였다. 본 연구에서는 1997년부터 2006년까지의 겨울철 NOAA (National Oceanic and Atmospheric Administration)의 AVHRR(Advanced Very High Resolution Radiometer) 위성영상의 8 sets의 총 108개 영상을 이용하여 적설분포면적을 추출하였고, 기상청의 지상기상관측소의 최심적설심 자료를 이용하여 GIS 자료를 구축함으로써 적설심의 공간적 분포를 추출하였다. 이를 국내 5대유역인 한강, 낙동강, 금강, 영산강, 섬진강 유역에 대하여 융설모형의 주요 매개변수인 적설분포면적, 유역 평균, 최대 적설심과 적설분포감소비곡선을 구축하였다. 그 중 적설분포면적감소곡선 (SDC : Snow cover Depletion Curve)는 적설분포면적의 감소형태를 나타내주는 지표로써 융설의 가장 민감한 매개변수이다. 이를 국내 5대강 유역에 대해 구축하여 정량화하였다.

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Multi-temporal image derived Ratio Vegetation Index and NDVI in a landslide prone region

  • Paramarthalingam, Rajakumar;Shanmugam, Sanjeevi
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.257-259
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    • 2003
  • Landuse maps are prepared from satellite imagery and field observations were conducted at various locations in the study area. Compared to the field data and NDVI and RVI thematic maps, NDVI is better than RVI, because it compensates for changing illumination conditions, surface slope, aspect and other factors. Clouds, water and snow have negative values for RVI and NDVI. Rock and bare soils have similar reflectance in both NIR and visible band, so RVI and NDVI are near zero. In forest areas with good vegetation cover, NDVI is high and landslide occurrence is less. But if annual and biennial vegetations are present and if cultivation practices are changed frequently, NDVI is medium and landslide occurrence is moderate. In areas where deforestation and settlement is in progress, NDVI is less and landslide occurrence is more. The NDVI FCC thematic map may be used as an important layer in GIS application for landslide studies. Analyzing other layers such as slope, rainfall, soil, geology, drainage, lineament, etc with NDVI FCC layer will give a better idea about the identity of landslide prone areas.

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Possibility Study of Estimating Maximum Depth of Daily Snow Cover by using Algorithm (알고리즘을 이용한 일최심신적설 측정 가능성 연구)

  • Lee, Gun;Kim, Dongkyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.170-170
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    • 2017
  • 본 연구의 목표는 극한 지역의 대비 시스템을 구축하기 위하여 인공 신경망(Artificial Neural Networks)을 이용하여 보다 관측하기 쉬운 기상 인자들로부터 적설량을 실시간 측정 가능성을 제시하는 것이다. 본 연구에서 사용한 데이터베이스는 기상청의 기상자료개방포털에서 사람이 직접 측정한 종관기상관측의 자료다. 이 중에서 일최대 기온, 일최저 기온, 일평균 기온, 강수량을 사용하여 오차를 줄여나가는 최적화방법으로 인공 신경망 시스템을 설계하였다. 설계된 시스템으로 500회 시뮬레이션한 연구 결과는 상관계수가 적설량 측정에 대한 인공 신경망의 크기(노드의 개수)와 관계없이 평균적으로 0.8627인 것을 보여준다. 추가적으로 보조 입력 값인 고도를 사용한 결과, 성능은 좋아졌지만 상관계수의 차이는 평균 0.0044로 미세했다. 또한 Cross-Validation을 통해 기존의 보간법인 Kriging기법과 비교하여 미 관측 지역에서 인공 신경망(ANNs) 사용이 Kriging기법 보다 우수하다는 것을 2차원 Regression's map을 통해 나타냈다. 마지막으로 오차가 크게 발생했을 경우 보안할 수 있는 확률적인 방안을 제시하였다.

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