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1.
Gianluca Loffredo Filippo Frontera Damiano Pellicciotta Alessandro Pisa Vito Carassiti Stefano Chiozzi Federico Evangelisti Luca Landi Michele Melchiorri Stefano Squerzanti 《Experimental Astronomy》2005,20(1-3):413-420
We will report on the current configuration of the X-ray facility of the University of Ferrara recently used to perform reflectivity tests of mosaic crystals and to calibrate the experiment JEM–X aboard Integral. The facility is now located in the technological campus of the University of Ferrara in a new building (named LARIX laboratory= ̳LARge ̳Italian ̳X-ray facility) that includes a tunnel 100 m long with, on the sides, two large experimental rooms. The facility is being improved for determining the optical axis of mosaic crystals in Laue configuration, for calibrating Laue lenses and hard X-ray mirror prototypes. 相似文献
2.
Pesaresi Damiano Picozzi Matteo &#;iv&#;i&#; Mladen Lenhardt Wolfgang Mucciarelli Marco Elia Luca Zollo Aldo Gosar Andrej 《Natural Hazards》2016,84(2):431-436
Since 2002 the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) in Udine (Italy), the Agencija Republike Slovenije za Okolje (ARSO) in Ljubljana (Slovenia) and the Zentralanstalt für Meteorologie und Geodynamik (ZAMG) in Vienna (Austria), are collecting, analyzing, archiving and exchanging seismic data in real time, initially in the framework of the EU Interreg IIIa Italia-Austria project “Trans-national seismological networks in the South-Eastern Alps”. As outcome of the successful cooperation, in the 2013 OGS, ARSO and ZAMG decided to officially merge their seismic monitoring efforts into the “Central and Eastern European Earthquake Research Network—CE3RN”. This work reports the results of a nine-month real-time test of the earthquake early warning (EEW) algorithm probabilistic and evolutionary early warning system carried out at the CE3RN. The study allowed identifying the actions to be implemented in order to let the CE3RN become in the next future an efficient cross-border EEW system.
相似文献3.
Computer-assisted Image Analysis can be succesfully used to derive quantitative information about grain-size distribution, particle shape and fabric on both consolidated and unconsolidated solid aggregates. We have developed a new analytical method that provides a series of quantitative textural parameters from whatever particulate deposits by combining commercial image acquisition system with devoted C-software. After exhaustive tests of the method, we applied it to a widespread Quaternary ignimbrite formation in central Italy (the Orvieto-Bagnoregio formation). The results suggest some new aspects of emplacement mechanisms of ignimbrites: (1) elongated particles shows variable degrees of flow-related preferred orientation both on horizontal and vertical planes; (2) vertical variations of flow-related preferred particle orientations follow a “zig-zag” pattern that we interpret to result from deposition by progressive aggradation during the passage of a particulate flow. The filling up of paleovalleys by means of progressive aggradation proceeds flank to flank due to alternating flow directions, induced by the already deposited material; (3) the occurrence of vertically spaced peaks on the strength of clast orientation suggests the existence of discrete depositional units deposited by aggradation from an unsteady but persisting flow. Strong fabrics are inferred to result from the high amount of shear stress imparted to particles at the depositional boundary layer, which at the same time can be responsible for the development of the basal inversely graded layer. Image analysis can also provide useful indications of paleoflow directions, paleotopographic details and ignimbrite source areas. 相似文献
4.
F. Frontera A. Pisa G. Loffredo D. Pellicciotta V. Carassiti F. Evangelisti K. Andersen P. Courtois L. Amati E. Caroli T. Franceschini G. Landini S. Silvestri J. Stephen 《Experimental Astronomy》2005,20(1-3):241-251
A review of the HAXTEL project devoted to the development of a Laue lens telescope for hard X-/gamma-ray observation of the continuum spectra of celestial sources is presented. Main design properties, open issues, the status of the project and an example of multi-lens configuration with sensitivity expectations are discussed. 相似文献
5.
Big Data Analytics for Earth Sciences: the EarthServer approach 总被引：1，自引：0，他引：1
Peter Baumann Paolo Mazzetti Joachim Ungar Roberto Barbera Damiano Barboni Alan Beccati 《International Journal of Digital Earth》2016,9(1):3-29
Big Data Analytics is an emerging field since massive storage and computing capabilities have been made available by advanced e-infrastructures. Earth and Environmental sciences are likely to benefit from Big Data Analytics techniques supporting the processing of the large number of Earth Observation datasets currently acquired and generated through observations and simulations. However, Earth Science data and applications present specificities in terms of relevance of the geospatial information, wide heterogeneity of data models and formats, and complexity of processing. Therefore, Big Earth Data Analytics requires specifically tailored techniques and tools. The EarthServer Big Earth Data Analytics engine offers a solution for coverage-type datasets, built around a high performance array database technology, and the adoption and enhancement of standards for service interaction (OGC WCS and WCPS). The EarthServer solution, led by the collection of requirements from scientific communities and international initiatives, provides a holistic approach that ranges from query languages and scalability up to mobile access and visualization. The result is demonstrated and validated through the development of lighthouse applications in the Marine, Geology, Atmospheric, Planetary and Cryospheric science domains. 相似文献
6.
Podzols that have developed on glacial and periglacial features provide the opportunity to reconstruct glacial evolution after the Last Glacial Maximum (LGM) using different soil indices. Analysing 17 soils classified as podzol, we used the crystallinity ratio of free iron oxides (CRF) on both the A and Bs horizons, and absolute ages for the same landforms containing the soil profile, to create dating curves. Two equations were generated: age = 4566.9 × ln (CRF) + 1760 (1), and age = 3907 × ln (CRF) + 3508.2 (2). The reliability of the curves was evaluated with the Feo/Fed ratio, and with the difference of ages calculated using both equations. Equation (2) is considered more reliable because the A horizon may be influenced by new pedogenesis on the pre-existing podzol, leading to the development of a new type of soil. By dating the soils, we reconstructed the glacial history of the three main upper branches of the LGM Adda Glacier in the Central Italian Alps, specifically the Stelvio Pass area (ST), Gavia Pass area (GV), and the Val Viola valley (VV). Seven glacial advances were identified at 16.7–14.7 ka (phase I), 12.3 ka (phase II), 11 ka (phase III), 10–9.7 ka (phase IV), 9 ka (phase V), 7.5 ka (phase VI) and 5.3 ka (phase VII). The first five phases are chronologically similar to the main Late Pleistocene–Early Holocene phases recorded in the Central European Alps. The last two Holocene phases, which are both longer in duration than the Little Ice Age, are recorded in ST and GV. Interestingly, these phases generally are not recorded in the rest of the Central European Alps, where the late Holocene glaciers were smaller than their present size. 相似文献
7.
A statistical study of magnetosphere–ionosphere coupling in the Lyon–Fedder–Mobarry global MHD model
B. Zhang W. Lotko M.J. Wiltberger O.J. Brambles P.A. Damiano 《Journal of Atmospheric and Solar》2011,73(5-6):686-702
The statistics of magnetosphere–ionosphere (MI) coupling derived from a two-month long run of the Lyon–Fedder–Mobarry (LFM) global simulation model are investigated. MI coupling characteristics such as polar cap potential and field-aligned current (FAC), downward Poynting flux and vorticity of ionospheric convection are compared with observed statistical averages and with results from the Weimer 05 empirical model. The comparisons for eight different IMF clock-angle orientations show that the LFM model produces reasonably accurate average distributions of the Region I and Region II currents. Both current systems have average amplitudes similar to those observed by the Iridium satellite constellation; however, the average LFM amplitudes are smaller by a factor of two compared with the values from the Weimer 05 model. The comparisons of polar cap potential show that the LFM model produces reasonable patterns of ionospheric convection, but the average cross polar cap potential (CPCP) is greater than the observed results by a factor of approximately 2 and greater than Weimer 05 by a factor of 1.5. The differences in convection in LFM results relative to the Weimer 05 model accounts for much of the difference in the Poynting flux patterns and integrated power produced by the two models. The comparisons of average ionospheric field-aligned vorticity show good agreement on the dayside; however, the LFM model gives higher nightside vorticity which may imply that the ionospheric conductance on the nightside is too small in the simulation. 相似文献
8.
G. Loffredo F. Frontera D. Pellicciotta A. Pisa V. Carassiti S. Chiozzi F. Evangelisti L. Landi M. Melchiorri S. Squerzanti 《Experimental Astronomy》2004,18(1-3):1-11
We will report on the equipment and performance of the X-ray facility of the University of Ferrara. Initially developed to
test the PDS (Phoswich Detection System) instrument aboard the BeppoSAX satellite and to perform reflectivity measurements
of mosaic crystal samples of HOPG (Highly Oriented Pyrolytic Graphite), with time the facility has been improved and its applications
extended. Now these applications include test and calibration of hard X-ray (> 10 keV) detectors, reflectivity measurements
of hard X-ray mirrors, reflectivity tests of crystals and X-ray transparency measurements. The facility is being further improved
in order to determine the optical axis mosaic crystals in Laue configuration within a project devoted to develop a hard X-ray
(> 60 keV) focusing optics (Pisa, A. et al.: in press, Feasibility study of a Laue lens for hard X-rays for space astronomy,
SPIE Proc., 5536). 相似文献
9.
10.
The role of infiltration processes in steep slope stability of pyroclastic granular soils: laboratory and numerical investigation 总被引：1，自引：0，他引：1
Rainfall-induced landslides on steep slopes are a common feature in much of Italy’s mountain areas covered by shallow-pyroclastic
deposits. Generally, these deposits are unsaturated and have a slope angle higher than 40°–50°; hence their stability is due
to the positive effect of matric suction on soil shear strength. During rainfall, rainwater infiltration causes a decrease
in suction, which in turn causes changes in soil mechanical and hydraulic properties, leading towards an instability process.
However, the response of pyroclastic soil slopes to rainwater infiltration is not fully understood. The aim of this study
is to link slope instability to the infiltration process on the basis of advanced geotechnical characterization, in situ monitoring
and numerical analysis calibrated through a back-analysis of well-instrumented flume tests. 相似文献