• Title/Summary/Keyword: Remote Area

Search Result 2,193, Processing Time 0.036 seconds

VALIDITY OF NDVI-BASED BIOPHYSICAL PARAMETERS FOR ECOSYSTEM MODELS

  • Lee, Kyu-Sung;Jang, Ki-Chang;Kim, Tae-Geun;Lee, Seung-Ho;Cho, Hyun-Guk
    • Proceedings of the KSRS Conference
    • /
    • v.2
    • /
    • pp.543-546
    • /
    • 2006
  • NDVI has been very frequently used to estimate several biophysical parameters that are required for ecosystem models. Leaf area index (LAI), canopy closure, and biomass are among those biophysical parameters that are estimated by empirical relationship with NDVI. However, the type of remote sensing signals (raw DN value, at-sensor radiance, atmospherically corrected reflectance) used can vary the calculation of NDVI. In this study, we tried to attempt to compare the influence of NDVI linked with forest LAI for the watershed-scale ecosystem models to estimate evapotranspiration. Landsat ETM+ data were used to obtain various NDVI values over the study area in central Korea. The NDVI-based LAI and the resultant evapotranspiration estimation were greatly varied by the remote sensing signal applied.

  • PDF

USING MODIS DATA TO ESTIMATE THE SURFACE HEAT FLUXES OVER TAIWAN'S CHIAYI PLAIN

  • Ho, Han-Chieh;Liou, Yuei-An;Wang, Chuan-Sheng
    • Proceedings of the KSRS Conference
    • /
    • 2008.10a
    • /
    • pp.317-319
    • /
    • 2008
  • Traditionally, it is measured by using basin or empirical formula with meteorology data, while it does not represent the evaportransporation over a regional area. With the advent of improved remote sensing technology, it becomes feasible to assess the ET over a regional scale. Firstly, the IMAGINE ATCOR atmospheric module is used to preprocess for the MODIS imagery. Then MODIS satellite images which have been corrected by radiation and geometry in conjunction with the in-situ surface meteorological measurement are used to estimate the surface heat fluxes such as soil heat flux, sensible heat flux, and latent heat flux. In addition, the correlation coefficient between the derived latent heat and the in-situ measurement is found to be over 0.76. In the future, we will continue to monitor the surface heat fluxes of paddy rice field in Chiayi area.

  • PDF

USING REMOTELY SENSED DATA TO ESTIMATE THE SURFACE HEAT FLUXES OVER TAIWAN'S CHAIYI PLAIN

  • Chang, Tzu-Yin;Liou, Yuei-An
    • Proceedings of the KSRS Conference
    • /
    • 2007.10a
    • /
    • pp.422-425
    • /
    • 2007
  • Traditionally, surface energy fluxes are obtained by model simulations or empirical equations with auxiliary meteorological data. These methods may not effectively represent the surface heat fluxes in a regional scale due to scene variability. On the other hand, remote sensing has the advantage to acquire data of a large area in an instantaneous view. The remotely sensed data can be further used to retrieve surface radiation and heat fluxes over a large area. In this study, the airborne and satellite images in conjunction with meteorological data and ground observations were used to estimate the surface heat fluxes over Taiwan's Chaiyi Plain. The results indicate that surface heat fluxes can be properly determined from both airborne and satellite images. The correlation coefficient of surface heat fluxes with in situ corresponding observations is over 0.60. We also observe that the remotely sensed data can efficiently provide a long term monitoring of surface heat fluxes over Taiwan's Chaiyi Plain.

  • PDF

Design on Integrated Land and Water Resources Management System Based on Remote Sensing and GIS in Shehezi City

  • Zhu, Gaolong;Chen, Xiuwan
    • Proceedings of the KSRS Conference
    • /
    • 2002.10a
    • /
    • pp.500-505
    • /
    • 2002
  • Based on the real-time monitoring by remote sensing and dynamic management by GIS on agricultural land and water resources in arid area, we solved the practicability and popularization of small-scale spatial information service system. Through demonstration, the standards of spatial information service database of agricultural land and water resources is set up, and the agricultural land and water resources management system in Shehezi City of Xinjiang Autonomy is established, which provides periodically the spatial information services needed by agricultural production to support for sustainable development in arid area.

  • PDF

Analysis of Sea Surface Wind over the Complex Coastal Area Using SAR images (SAR영상에 의한 복잡해안지역 해상풍 분석)

  • Hwang, Hyo-Jung;Kim, Hyun-Goo
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.11a
    • /
    • pp.482-483
    • /
    • 2009
  • This paper is foundation paper about national wind map verification using remote sensing, based on analysis of comparison between numerical simulation and remote sensing on complex coastal area of regional coast. As a result analysis using NCAR/NCEP, wind direction of numerical simulation and remote sensing is same. but, wind direction of some case is showed different. Such as this result, if it would be used without verification of analyzed data, present ability of occurring lots of error, and it will be verified based on using survey data or atmospheric data.

  • PDF

Target Positioning in Remote Area Using Strip Sensor Modeling of SPOT Imagery (SPOT 위성영상의 스트립 센서모델링을 이용한 비접근지역 위치결정 연구)

  • Kim, Man-Jo;Hwang, Chi-Jung
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.155-160
    • /
    • 2012
  • In this paper, a strip modeling method is developed for the acquisition of target positions in remote area and validated using the imagery of SPOT satellite. This method utilizes the parameters given in header files and constructs a camera model without ground control points. In most cases, the root mean squared error of check points is less than pixel size with one ground control point. The model error of reference image is evaluated using ground control points and used to remove the model error of target images acquired along the same satellite orbit, which enables one to calculate target positions in remote area where no ground control points are available.

Generation of Forest Leaf Area Index (LAI) Map Using Multispectral Satellite Data and Field Measurements

  • Lee, Kyu-Sung;Kim, Sun-Hwa;Park, Yoon-Il;Jang, Ki-Chang
    • Korean Journal of Remote Sensing
    • /
    • v.19 no.5
    • /
    • pp.371-380
    • /
    • 2003
  • The primary objective of this study is to develop a suitable methodology to generate forest leaf area index (LAI) map at regional and local scales. To build empirical models, we collected the LAI values at 30 sample plots over the forest within the kyongan watershed area by the field measurements using an optical instrument. Landsat-7 ETM+ multispectral data obtained at the same growing season with the field LAI measurement were used. Three datasets of remote sensing signal were prepared for analyzing the relationship with the field measured LAI value and they include raw DN, atmospherically corrected reflectance, and topographically corrected reflectance. From the correlation analysis and regression model development, we found that the radiometric correction of topographic effects was very critical step to increase the sensitivity of the multispectral reflectance to LAI. In addition, the empirical model to generate forest LAI map should be separately developed for each of coniferous and deciduous forest.

A Study on Suitability Mapping for Artificial Reef Facility using Satellite Remotely Sensed Imagery and GIS (위성원격탐사자료와 GIS를 이용한 인공어초 시설지 적지 선정 공간분포도 작성 연구)

  • 조명희;김병석;서영상
    • Korean Journal of Remote Sensing
    • /
    • v.17 no.1
    • /
    • pp.99-109
    • /
    • 2001
  • In order to establish effective fishing ground environment equipment and artificial reef in coastal area, the methodology to select the most suitable area for artificial reef should be applied after analyzing the correlation between fishing ground environment and ocean environment. In this paper, thematic maps were prepared by using satellite remote sensing and GIS for the sea surface temperature, chlorophyll, transparency, the depth of sea water and the condition of submarine geologic which are considered as the most elements when selecting suitable area for artificial reef in Tong-Yong bay. Then, the most suitable area for artificial reef was selected by giving weight score depending on the suitable condition of this area and analyzing spatial data. The results showed it makes possible for this methodology, which selects the suitable area for artificial reef using satellite remote sensing and GIS, to manage the institution of artificial reef more entirely and efficiently through analyzing and visualizing.

A STUDY OF ESTIMATION GROUND SURFACE TEMPERATURE BY TIME-SHIFT PROCESSING

  • Yano, Koji;KAJIWARA, Koji;HONDA, Yoshiaki;Moriyama, Masao
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.798-800
    • /
    • 2003
  • The time shift processing of ground measured surface temperature with the meteorological variables has no evaluated function. We introduce new evaluating function. To use this evaluating function, the algorithm of time-shift processing will be able to be reliable and get error-bar for all moving measured point's data. We will finally obtain the area averaged surface temperature by land observation.

  • PDF

DEVELOPMENT OF A VALLEY MANAGEMENT SYSTEM FOR GIS AND REMOTE SENSING EDUCATION

  • Wu, Mu-Lin;Wong, Deng-Ching;Wang, Yu-Ming
    • Proceedings of the KSRS Conference
    • /
    • v.2
    • /
    • pp.570-573
    • /
    • 2006
  • College GIS and remote sensing education usually consists of commercial software packages implementations in the classroom. Computer programming is quite important when college graduates work in private or public sectors relevant with GIS and remote sensing implementations. The objective of this paper was to develop a valley management system which implements GIS and remote sensing as the key components for education. The Valley Authority is entitled with water resource protection for sustainable drinking water supply of the second largest city in Taiwan. The test area consists of three different government agencies, Forest Service, EPA, and Water Resource Agency. Materials were provided by the Valley Authority in ArcGIS file format. MapObjects have made the GIS development process much easier. Remote sensing with image manipulation functions were provided by computer programming with Visual Baisc.NET and Visual C#.NET. Attributes inquiry are performed by these two computer languages as well. ArcGIS and ArcPad are also used for simple GIS manipulations of the test area. Comparison between DIY and commercial GIS can be made by college students. Functions provided by the developed valley management system depending on how many map layers have been used and what types of MapObjects components have been used. Computer programming experience is not essential but can be helpful for a college student. The whole process is a step-by-step sequence which college students can modify to depict their capability in GIS and remote sensing. The development process has gone through one semester, three hours every week in 18 weeks. College students enrolled in this class entitled with GIS showed remarkable progresses both in GIS and remote sensing.

  • PDF