Partner und Internationale Organisationen
(Englisch)
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Aaristotele University of Thessaloniki, Insitut Cartographic de Catalunya, Tu Graz, Politechnico di Milano, ETH Zürich
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Abstract
(Englisch)
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Monitoring environmental changes is an issue which is not only rapidly gaining importance, as awareness of its value and demand for it are increasing, but is also becoming more complicated and challenging when considering the modern, accelerated rate of environmental change. Supported by recent research advancements, photogrammetry and radargrammetry have established themselves as key methodologies for monitoring the environment, as they provide an abundance of data and updating abilities. In addition to sharing objectives, photogrammetry and radargrammetry are quite compatible and therefore can both benefit from mutual cooperation. To improve the effectiveness of research for environmental monitoring within these two disciplines, and to acquire a better perspective of european needs in this matter, this concerted action for coordination of reseach is performed on the issue of modelling and monitoring the environment with digital elevation model generation and geocoded image production of an test area in Catalonia/Spain by using radar and electrooptical sensors. The optimal way of combination of these two complementing techniques will be identified by comparing their performance in terms of accuracy, investigating their synergetic use and identifying the potential for transferring methodologies between them in order to optimize environmental monitoring in european context. Within an international research network consisting of institutes of Spain, Greece, Italy and Austria, IGP concentrated on the generation and evaluation of digital elevation models (DEMs) using optical and microwave sensors. Both sensors are capable for measuring the topographic height by measuring phase differences (SAR) or point parallaxes (optical). After an error evaluation of the resulting DEMs, it showed up, that reasons for failure of the height measurement differ in both techniques, offering the possibility of a complementary use of both techniques. In consequence, different approaches for sensor fusion have been tested to obtain DEMs of higher accuracy. A new technique for filtering SAR and optical DEMs has been developed, which filters height errors and replaces them by less affected values of the other DEM. This technique reduces the amount of large errors drastically and produces a fused DEM of higher accuracy, which will be used in our further investigations.
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