5,739 research outputs found
Applications of ISES for vegetation and land use
Remote sensing relative to applications involving vegetation cover and land use is reviewed to consider the potential benefits to the Earth Observing System (Eos) of a proposed Information Sciences Experiment System (ISES). The ISES concept has been proposed as an onboard experiment and computational resource to support advanced experiments and demonstrations in the information and earth sciences. Embedded in the concept is potential for relieving the data glut problem, enhancing capabilities to meet real-time needs of data users and in-situ researchers, and introducing emerging technology to Eos as the technology matures. These potential benefits are examined in the context of state-of-the-art research activities in image/data processing and management
The contribution of multitemporal information from multispectral satellite images for automatic land cover classification at the national scale
Thesis submitted to the Instituto Superior de EstatÃstica e Gestão de
Informação da Universidade Nova de Lisboa in partial fulfillment of the
requirements for the Degree of Doctor of Philosophy in Information Management – Geographic Information SystemsImaging and sensing technologies are constantly evolving so that, now, the latest
generations of satellites commonly provide with Earth’s surface snapshots at very short
sampling periods (i.e. daily images). It is unquestionable that this tendency towards
continuous time observation will broaden up the scope of remotely sensed activities.
Inevitable also, such increasing amount of information will prompt methodological
approaches that combine digital image processing techniques with time series analysis for
the characterization of land cover distribution and monitoring of its dynamics on a frequent
basis. Nonetheless, quantitative analyses that convey the proficiency of three-dimensional
satellite images data sets (i.e. spatial, spectral and temporal) for the automatic mapping of
land cover and land cover time evolution have not been thoroughly explored. In this
dissertation, we investigate the usefulness of multispectral time series sets of medium spatial
resolution satellite images for the regular land cover characterization at the national scale.
This study is carried out on the territory of Continental Portugal and exploits satellite
images acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) and
MEdium Resolution Imaging Spectrometer (MERIS). In detail, we first focus on the analysis
of the contribution of multitemporal information from multispectral satellite images for the
automatic land cover classes’ discrimination. The outcomes show that multispectral
information contributes more significantly than multitemporal information for the automatic
classification of land cover types. In the sequence, we review some of the most important
steps that constitute a standard protocol for the automatic land cover mapping from satellite
images. Moreover, we delineate a methodological approach for the production and
assessment of land cover maps from multitemporal satellite images that guides us in the
production of a land cover map with high thematic accuracy for the study area. Finally, we
develop a nonlinear harmonic model for fitting multispectral reflectances and vegetation
indices time series from satellite images for numerous land cover classes. The simplified
multitemporal information retrieved with the model proves adequate to describe the main
land cover classes’ characteristics and to predict the time evolution of land cover classes’individuals
Use of multi-angle high-resolution imagery and 3D information for urban land-cover classification: a case study on Istanbul
The BELSPO-MAMUD project focuses on the use of Remote Sensing data for measuring and modelling urban dynamics. Remote sensing is a wonderful tool to produce long time-series of high resolution maps of sealed surface useful for this purpose. In the urban context of Istanbul, a very dynamic city, recent high resolution satellite images and medium resolution images from the past have been exploited to calibrate and validate a regression-based sub-pixel classification method allowing this production.
In this context it’s a tricky task for several reasons: prominent occurrence of shadowed and occluded areas and urban canyons, spectral confusions between urban and non-urban materials at ground and roof levels, moderately hilly relief ... To cope with these difficulties the combined use of three types of data may be helpful: diachronic (i), multi-angle and 3D data. A master multispectral and panchromatic QuickBird image and a panchromatic Ikonos stereopair, all acquired in March 2002, were used in combination with a multispectral and panchromatic Ikonos image of May 2005. A DSM was generated from the Ikonos stereopair and building vector file. It was used for orthorectification, building height estimation and classification procedure. The area covered by the high resolution products was divided in 3 partitions and each one was classified independently. This application demonstrates that recent high resolution land-cover classification produced using multi-date, multi-angle and DSM can be used to produce sealed surface maps from longer timeseries of medium resolution images over large urban areas enabling so the analysis of urban dynamics
The use of ERTS-1 multispectral imagery for crop identification in a semi-arid climate
Crop identification using multispectral satellite imagery and multivariate pattern recognition was used to identify wheat accurately in Greeley County, Kansas. A classification accuracy of 97 percent was found for wheat and the wheat estimate in hectares was within 5 percent of the USDA's Statistical Reporting Service estimate for 1973. The multispectral response of cotton and sorghum in Texas was not unique enough to distinguish between them nor to separate them from other cultivated crops
Advancements in Multi-temporal Remote Sensing Data Analysis Techniques for Precision Agriculture
L'abstract è presente nell'allegato / the abstract is in the attachmen
The comparative evaluation of ERTS-1 imagery for resource inventory in land use planning
The author has identified the following significant results. Multidiscipline team interpretation and mapping of resources for Crook County is complete on 1:250,000 scale enlargements of ERTS imagery and 1:120,000 hi-flight photography. Maps of geology, soils, vegetation-land use and land resources units were interpreted to show limitations, suitabilities, and geologic hazards for land use planning. Mapping of lineaments and structures from ERTS imagery has shown a number of features not previously mapped in Oregon. A multistage timber inventory of Ochoco National Forest was made, using ERTS images as the first stage. Inventory of forest clear-cutting practices was successfully demonstrated with color composites. Soil tonal differences in fallow fields correspond with major soil boundaries in loess-mantled terrain. A digital classification system used for discriminating natural vegetation and geologic material classes was successful in separating most major classes around Newberry Caldera, Mt. Washington, and Big Summit Prairie
Literature review of the remote sensing of natural resources
Abstracts of 596 documents related to remote sensors or the remote sensing of natural resources by satellite, aircraft, or ground-based stations are presented. Topics covered include general theory, geology and hydrology, agriculture and forestry, marine sciences, urban land use, and instrumentation. Recent documents not yet cited in any of the seven information sources used for the compilation are summarized. An author/key word index is provided
Quarterly literature review of the remote sensing of natural resources
The Technology Application Center reviewed abstracted literature sources, and selected document data and data gathering techniques which were performed or obtained remotely from space, aircraft or groundbased stations. All of the documentation was related to remote sensing sensors or the remote sensing of the natural resources. Sensors were primarily those operating within the 10 to the minus 8 power to 1 meter wavelength band. Included are NASA Tech Briefs, ARAC Industrial Applications Reports, U.S. Navy Technical Reports, U.S. Patent reports, and other technical articles and reports
Trying to break new ground in aerial archaeology
Aerial reconnaissance continues to be a vital tool for landscape-oriented archaeological research. Although a variety of remote sensing platforms operate within the earth’s atmosphere, the majority of aerial archaeological information is still derived from oblique photographs collected during observer-directed reconnaissance flights, a prospection approach which has dominated archaeological aerial survey for the past century. The resulting highly biased imagery is generally catalogued in sub-optimal (spatial) databases, if at all, after which a small selection of images is orthorectified and interpreted. For decades, this has been the standard approach. Although many innovations, including digital cameras, inertial units, photogrammetry and computer vision algorithms, geographic(al) information systems and computing power have emerged, their potential has not yet been fully exploited in order to re-invent and highly optimise this crucial branch of landscape archaeology. The authors argue that a fundamental change is needed to transform the way aerial archaeologists approach data acquisition and image processing. By addressing the very core concepts of geographically biased aerial archaeological photographs and proposing new imaging technologies, data handling methods and processing procedures, this paper gives a personal opinion on how the methodological components of aerial archaeology, and specifically aerial archaeological photography, should evolve during the next decade if developing a more reliable record of our past is to be our central aim. In this paper, a possible practical solution is illustrated by outlining a turnkey aerial prospection system for total coverage survey together with a semi-automated back-end pipeline that takes care of photograph correction and image enhancement as well as the management and interpretative mapping of the resulting data products. In this way, the proposed system addresses one of many bias issues in archaeological research: the bias we impart to the visual record as a result of selective coverage. While the total coverage approach outlined here may not altogether eliminate survey bias, it can vastly increase the amount of useful information captured during a single reconnaissance flight while mitigating the discriminating effects of observer-based, on-the-fly target selection. Furthermore, the information contained in this paper should make it clear that with current technology it is feasible to do so. This can radically alter the basis for aerial prospection and move landscape archaeology forward, beyond the inherently biased patterns that are currently created by airborne archaeological prospection
Remote sensing in forestry: Promises and problems
There are no author-identified significant results in this report
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