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11.
Experimental analysis of different software packages for orientation and digital surface modelling from UAV images 总被引:1,自引:0,他引:1
Giovanna Sona Livio Pinto Diana Pagliari Daniele Passoni Rossana Gini 《Earth Science Informatics》2014,7(2):97-107
The use of UAVs finds application in a variety of fields, among which are the small scale surveys for environmental protection application. In this frame some experimental tests were carried out at Politecnico di Milano to assess metric accuracies of images acquired by UAVs and derived photogrammetric products. A block of 5 strips and 49 photos was taken by fixed wing system SenseFly, carrying a camera Canon Ixus 220HS on a rural area included in an Italian Park. Images are processed through bundle adjustment, automatic DEM extraction and orthoimages production steps with several software packages, with the aim to evaluate their characteristics, capabilities and weaknesses. The software packages tested were Erdas-LPS, EyeDEA (University of Parma), Agisoft Photoscan, Pix4UAV, PhotoModeler Scanner. For the georeferencing of the block 16 pre-signalized ground control points were surveyed in the area through GPS (NRTK survey). Comparison of results is given in terms of differences among orientation parameters and their accuracies. Moreover, comparisons among different digital surface models are evaluated. Furthermore, exterior orientation parameters, image points and ground points coordinates, obtained by the various software packages, were used as initial values in a comparative adjustment made by scientific in-house software. Paper confirms that computer vision software are faster in computation and, even if their main goal is not to pursue high accuracy in points coordinates determination, they seems to produce results comparable to those obtainable with standard photogrammetric approach. Agisoft Photoscan seems in this case to yield the best results in terms of quality of photogrammetric products. 相似文献
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Alberto D. Albani Sandra Donnici Rossana Serandrei-Barbero Peter C. Rickwood 《Continental Shelf Research》2010
Extensive sampling in the Lagoon and Gulf of Venice during the 1980s provided material to establish ‘base’ conditions for subsequent studies of distributions of benthic foraminiferal biotopes and sediments. 相似文献
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Aurèle Vuillemin Mapathe Ndiaye Rossana Martini Eric Davaud 《Swiss Journal of Geoscience》2011,104(1):55-66
Cement stratigraphy of carbonates aims to establish the chronology of processes involved in the rock diagenesis. Regional
cement stratigraphy allows correlations and understanding of the petrological heterogeneities in reservoirs and aquifers,
but is a long and rigorous approach. This article exposes a methodology of image analysis that facilitates the spatial correlation
of diagenetic events in carbonate rocks. Based on the statistical comparison of signals extracted from the red spectrum emission
of cathodoluminescence digital images, it gives via crosscorrelation a measure of similarity (values scaled from minimum −1
to maximum 1) between two cathodoluminescence facies. Cementation events and diagenetic chronologies can thus be quickly correlated
without the support of a full chronology, the model normally established on cement morphologies, petrological analyses and
cathodoluminescence zonation sequences. A case study from two Upper Kimmeridgian Mount Salève outcrops (France) illustrates
this methodology. Their diagenetic sequences recorded in cathodoluminescent cements are presented and being compared. The
final statistical similarity between the two outcrops reaches an index of R = 0.78. This result is sustained by petrological and geochemical analyses such as alizarine–ferricyanure stained thin sections,
X microfluorescence mapping of elements, and microthermometry of fluid inclusions. 相似文献
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Daniela Ruberti Marco Vigliotti Rossana Marzaioli Annamaria Pacifico Antonella Ermice 《Environmental Earth Sciences》2014,71(1):319-339
This study attempts to assess the aquifer vulnerability in the northeastern sector of the Campania Plain (southern Italy). The area is a highly populated region with anthropic impacts caused by rapid urban growth, quarrying, agricultural and industrial activities and uncontrolled waste storage. The main geologic feature of this plain is the alternation of alluvial/transitional and volcaniclastic deposits of Late Pleistocene–Holocene age. The study was performed integrating different sets of geologic and environmental data to restore the stratigraphic architecture and to assess anthropic impacts on subsoil. The reconstruction of stratigraphic subsurface architecture was based on remarkable geodatabase, concerning well log stratigraphies. Specific insights have been delineated on the volcaniclastic lithofacies heteropies across the entire area of study to highlight the differences in lithification degree and permeability. The contribution of pedogenesis on the reconstruction of the stratigraphic setting was also considered for the relative implications on groundwater quality concerns, as paleosols are usually regarded as aquitards. All of this information has been managed into a GIS project to produce a detailed 3D geological reconstruction, integrated with hydrogeological information to provide a model of the aquifer under study, highlighting sites of greater vulnerability to pollution. The anthropic impacts on subsoil were assessed by evaluating land-uses and overlaying the ANHI (Agricultural Nitrate Hazard Index) Map. The integration of the above datasets has allowed to check the reliability of the previsional empirical model with respect to the hydrostratigraphic model based on a thorough stratigraphic model and to verify the real potential of contamination. 相似文献
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Rossana Vai Francisco Luzón Ursula Iturrarán-Viveros Francisco J. Sánchez-Sesma 《Journal of Applied Geophysics》2009,67(1):1-8
Some numerical experiments are designed to elucidate geometrical details of fractures by studying scattering of elastic waves. The response in the time domain does not seem to provide much information. In the frequency domain, geometrical features of diffractors stamp a signature on reflected and diffracted wave fields. Results show that radiation patterns in the Mie regime are a promising device to infer some aspects such as shape and connectivity of the fractures. A combination of the direct and the indirect boundary element methods is used to compute numerical results. The numerical method is validated with analytic solutions for canonical problems. 相似文献
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Michel Villeneuve Jean-Jacques Cornée Agus Harsolumakso Rossana Martini et Louisette Zaninetti 《Eclogae Geologicae Helvetiae》2005,98(2):297-310
Resume. De nombreuses échelles stratigraphiques de l’?le de Timor ont vu le jour car les corrélations stratigraphiques étaient rendues
difficiles par la complexité tectonique de l’?le et par la variété des faciès. Dès les premiers travaux, plusieurs séries
ont été distinguées, regroupées en trois unités litho-structurales principales: unité allochtone, sub-autochtone et autochtone.
Les données stratigraphiques et géodynamiques récentes montrent que l’?le de Timor est en fait constituée par six unités litho-structurales,
chacune témoignant d’un épisode majeur de l’histoire géologique de l’Ile. Cette histoire consiste d’abord à la séparation,
au Jurassique, d’un bloc issu du continent de Gondwana (unité para-allochtone) qui est entré en collision avec l’arc volcanique
asiatique à l’Oligo-Miocène (unités allochtone et sub-allochtone). Cet ensemble a ensuite été séparé de l’Asie lors de l’ouverture
de la mer de Banda sud, au Miocène supérieur (unité sub-autochtone) pour finalement entrer en collision avec la marge nord
australienne au cours du Pliocène moyen (plateforme australienne et groupe de Kolbano). Timor est depuis incorporée à la marge
nord australienne (unité autochtone).
Ce travail présente les différentes échelles stratigraphiques de chaque nouvelle unité, des propositions de corrélations et
une comparaison avec les ?les voisines de Sumba et de Sulawesi pour aboutir à une proposition d’évolution géodynamique.
Manuscrit re?u le 13 février 2004 Révision acceptée le 14 février 2005 相似文献
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Michel Villeneuve Jean-Jacques Corne Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2004,336(16):1511-1520
Similar lithological and tectonic features indicate that Timor and Sulawesi islands were part of the same continental block. Timor was in the southern part of Sulawesi, then separated during Late Miocene time during the opening of the South Banda Sea basin. At this time Timor evolved as a part of an Upper Miocene volcanic arc that collided the Australian plate at the end of the Lower Pliocene (3.5 Ma). To cite this article: M. Villeneuve et al., C. R. Geoscience 336 (2004). 相似文献
20.
Triassic stratigraphy,facies and evolution of the Arabian shelf in the northern United Arab Emirates
Florian Maurer Roberto Rettori Rossana Martini 《International Journal of Earth Sciences》2008,97(4):765-784
This study provides a reconstruction of the Late Permian and Triassic depositional history of the Arabian shelf in the northern
United Arab Emirates based on facies analysis and foraminiferal biostratigraphy. The presented data show that sedimentation
occurred in three major sequences. From the Late Permian to Olenekian carbonates and evaporites were deposited in restricted
lagoons and tidal flats. After a hiatus, sedimentation resumed and continued until the Late Ladinian/Carnian, leading to the
deposition of a carbonate platform dominated by peritidal dolostones. A period of shelf exposure and erosion, spanning from
the Carnian to Norian, was followed by the third major sequence with sedimentation into the Early Jurassic. During this third
depositional sequence sedimentation changed from pure carbonate into mixed carbonate–siliciclastic deposits. This transition
reflects the global regression of the sea in the Late Triassic (Triasina hantkeni Zone) and the increased erosion of large parts of the Arabian hinterland. A comparison of the evolution of the Arabian shelf
in the study area with chronostratigraphic reference schemes for the Arabian Plate reveals remarkable differences in the distribution
of Middle and Upper Triassic sequences. These are most likely the result of poor biostratigraphic control on previously studied
formations in the region. 相似文献