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Troglia Gamba Micaela Truong Minh Duc Motella Beatrice Falletti Emanuela Ta Tung Hai 《GPS Solutions》2017,21(2):577-589
GPS Solutions - The hazardous effects of spoofing attacks on the global navigation satellite system (GNSS) receiver are well known. Technologies and algorithms to increase the awareness of GNSS... 相似文献
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Barbara Borzi Fabio Dell��Acqua Marta Faravelli Paolo Gamba Gianni Lisini Mauro Onida Diego Polli 《Bulletin of Earthquake Engineering》2011,9(2):675-690
The aim of this paper is to disseminate knowledge in the seismic science community about a possible tool which is not largely
popular, despite its potential usefulness. In this paper it will be shown how satellite remotely sensed images may represent
a powerful source of information where traditional sources of information are unable to deliver it, or at least to do so timely.
Even when traditional information flow can ensure delivery, an advantage may still be found in terms of sooner availability
and smaller amount of labour required. In the case shown here a vulnerability study was made on a vast industrial area in
the gulf of Siracusa, Sicily, Italy. A series of concurrent factors made it particularly troublesome to obtain information
on the structures found in the site (tanks, pipes, chimneys, roads, ...), required to suitably carry out the study. Satellite
images were then acquired to obtain the information needed. Processing of the images was carried out relying on in-house software
formerly developed for similar information extraction issues, and integrated with new, specifically developed elements, some
pieces of information were obtained useful for seismic risk evaluation. In particular, location, footprint, elevation of significant
structures (e.g. tanks, chimneys) could be evaluated, obtaining results in a format compatible with the most widespread GIS
(Geographic Information System) standards. Such compatibility allowed a considerable savings on labour time required to lay
a GIS of the area, which is a fundamental tool for risk and vulnerability analyses. 相似文献
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Spatial aspects of building and population exposure data and their implications for global earthquake exposure modeling 总被引：1，自引：1，他引：0
This paper discusses spatial aspects of the global exposure dataset and mapping needs for earthquake risk assessment. We discuss this in the context of development of a Global Exposure Database for the Global Earthquake Model (GED4GEM), which requires compilation of a multi-scale inventory of assets at risk, for example, buildings, populations, and economic exposure. After defining the relevant spatial and geographic scales of interest, different procedures are proposed to disaggregate coarse-resolution data, to map them, and if necessary to infer missing data by using proxies. We discuss the advantages and limitations of these methodologies and detail the potentials of utilizing remote-sensing data. The latter is used especially to homogenize an existing coarser dataset and, where possible, replace it with detailed information extracted from remote sensing using the built-up indicators for different environments. Present research shows that the spatial aspects of earthquake risk computation are tightly connected with the availability of datasets of the resolution necessary for producing sufficiently detailed exposure. The global exposure database designed by the GED4GEM project is able to manage datasets and queries of multiple spatial scales. 相似文献
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F. Dell&#x;Acqua P. Gamba G. Lisini 《ISPRS Journal of Photogrammetry and Remote Sensing》2009,64(5):482-489
This paper describes a semi-automatic procedure for cartographic mapping using high resolution SAR and interferometric SAR data. Various two-dimensional features are extracted and combined in order to achieve a basic yet effective recognition of the elements in the scene. Many relevant elements of the landscape are automatically extracted without requiring any deep interaction with the operator. Being based on geometric models assuming regularity of shapes and patterns, the procedure is well suited for detecting man-made features, such as the road network (outside and inside human settlements) and built-up areas. It can be used, however, to extract natural features, focusing on different geometric models. Moreover, extracted elements of the scene can be grouped into higher level ones, such as crossroads, bridges and overpasses, through data fusion at the feature level, because the procedure is characterized by a multi-scale, object-based approach. 相似文献
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Exploiting spectral and spatial information in hyperspectral urban data with high resolution 总被引：2，自引：0，他引：2
Dell'Acqua F. Gamba P. Ferrari A. Palmason J.A. Benediktsson J.A. Arnason K. 《Geoscience and Remote Sensing Letters, IEEE》2004,1(4):322-326
Very high resolution hyperspectral data should be very useful to provide detailed maps of urban land cover. In order to provide such maps, both accurate and precise classification tools need, however, to be developed. In this letter, new methods for classification of hyperspectral remote sensing data are investigated, with the primary focus on multiple classifications and spatial analysis to improve mapping accuracy in urban areas. In particular, we compare spatial reclassification and mathematical morphology approaches. We show results for classification of DAIS data over the town of Pavia, in northern Italy. Classification maps of two test areas are given, and the overall and individual class accuracies are analyzed with respect to the parameters of the proposed classification procedures. 相似文献
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This letter aims at the extraction of roads and road networks from high-resolution synthetic aperture radar data. Classical methods based on line detection do not use all the information available; indeed, in high-resolution data, roads are large enough to be considered as regions and can be characterized also by their statistics. This property can be used in a classification scheme. Therefore, this letter presents a road extraction method which is based on the fusion of classification (statistical information) and line detection (structural information). This fusion is done at the feature level, which helps to improve both the level of likelihood and the number of the extracted roads. The proposed approach is tested with two classification methods and one line extractor. Results on two different datasets are discussed. 相似文献
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Improving urban road extraction in high-resolution images exploiting directional filtering, perceptual grouping, and simple topological concepts 总被引：1，自引：0，他引：1
In this letter, the problem of detecting urban road networks from high-resolution optical/synthetic aperture radar (SAR) images is addressed. To this end, this letter exploits a priori knowledge about road direction distribution in urban areas. In particular, this letter presents an adaptive filtering procedure able to capture the predominant directions of these roads and enhance the extraction results. After road element extraction, to both discard redundant segments and avoid gaps, a special perceptual grouping algorithm is devised, exploiting colinearity as well as proximity concepts. Finally, the road network topology is considered, checking for road intersections and regularizing the overall patterns using these focal points. The proposed procedure was tested on a pair of very high resolution images, one from an optical sensor and one from a SAR sensor. The experiments show an increase in both the completeness and the quality indexes for the extracted road network. 相似文献
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Provides a first assessment of a coregistration technique suitable for multiangle fine spatial resolution synthetic aperture radar (SAR) images. The technique is based on crossroad and road junction extraction and matching and exploits recently introduced road extraction routines for SAR data. These features are matched using relational and geometrical analysis. Results are encouraging and show the possibility to exploit multiangle SAR available from future airborne and satellite missions. 相似文献
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