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61.
Rapid estimation of ground-shaking maps for seismic emergency management in the Campania Region of southern Italy 总被引:1,自引:1,他引:0
Vincenzo Convertito Raffaella De Matteis Luciana Cantore Aldo Zollo Giovanni Iannaccone Mauro Caccavale 《Natural Hazards》2010,52(1):97-115
Strong ground-shaking mapping soon after a moderate-to-large earthquake is crucial to recognize the areas that have suffered
the largest damage and losses. These maps have a fundamental role for emergency services, loss estimation and planning of
emergency actions by the Civil Protection Authorities. This is particularly important for areas with high seismic risk levels,
such as the Campania-Lucania Region in southern Italy. Taking advantage of the Irpinia Seismic Network (ISNet), a recently
installed dense and wide dynamic seismic network, we have developed a procedure for rapid estimation of ground-shaking maps
after moderate-to-large earthquakes (GRSmap). This uses an optimal data gridding scheme designed to account for bi-dimensional
features of strong ground-motion fields, such as directivity, radiation patterns and focal mechanisms, to which most damage
can be correlated. The basis of the mapping technique is a triangulation procedure to locally correct predicted data at the
triangle barycentres where their vertices correspond to seismic stations. The method has been tested off-line using a simulated
M 6.6 earthquake located at the centre of ISNet and applied to data of the 23 November 1980 Irpina M 6.9 earthquake recorded by a sparse network. This has highlighted its ability to predict peak ground-motion parameters of
large magnitude earthquakes with respect to the attenuation relationships. 相似文献
62.
63.
The nutation effects of an accreting disk around SS 433 are analyzed within the framework of the fully relativistic model of Fang and Ruffini.Paper presented at the Lembang-Bamberg IAU Colloquium No. 80 on Double Stars: Physical Properties and Generic Relations, held at Bandung, Indonesia, 3–7 June, 1983. 相似文献
64.
D. Calzetti J. Einasto M. Giavalisco R. Ruffini E. Saar 《Astrophysics and Space Science》1987,137(1):101-106
The observational data on the amplitude of the correlation function of galaxies in the direction of the Coma cluster are confronted with an analytic formula derived for a self-similar observer-homogeneous structure. 相似文献
65.
On the influence of degeneracy on gravitational instability 总被引:1,自引:0,他引:1
The influence of degeneracy on gravitational instability in a collisionless particle system with a semi-degenerate distribution function is discussed. The collapse time and the Landau damping time are calculated. The influence of degeneracy on Jeans wave number and on stability have important implications in the theory of galaxy formation in a universe dominated by fermionic dark matter. 相似文献
66.
This article addresses the alternatives posed by urban decentralization as a new institutional framework within which change in city planning goals and administrative practices can take place. Considering that, traditionally, the professions of city planning and public administration have been haunted by a low level of implementation of plans and a high level of dissatisfaction with public-service delivery, the attempt is made to identify the root causes of the two shortcomings. In the process, the thesis is sustained that neighbourhoods endowed with formal decision-making powers have the potential to increase the degree of implementation of plans and to ensure greater efficiency in, and satisfaction with, the delivery of public services. A case study provides a data base to illustrate a number of working hypotheses. 相似文献
67.
Simone Bianchi Raffaella Schneider 《Monthly notices of the Royal Astronomical Society》2007,378(3):973-982
The presence of dust at high redshift requires efficient condensation of grains in supernova (SN) ejecta, in accordance with current theoretical models. Yet observations of the few well-studied supernovae (SNe) and supernova remnants (SNRs) imply condensation efficiencies which are about two orders of magnitude smaller. Motivated by this tension, we have (i) revisited the model of Todini & Ferrara for dust formation in the ejecta of core collapse SNe, and (ii) followed, for the first time, the evolution of newly condensed grains from the time of formation to their survival – through the passage of the reverse shock – in the SNR. We find that 0.1–0.6 M⊙ of dust form in the ejecta of 12–40 M⊙ stellar progenitors. Depending on the density of the surrounding interstellar medium, between 2 and 20 per cent of the initial dust mass survives the passage of the reverse shock, on time-scales of about 4–8 × 104 yr from the stellar explosion. Sputtering by the hot gas induces a shift of the dust size distribution towards smaller grains. The resulting dust extinction curve shows a good agreement with that derived by observations of a reddened QSO at z = 6.2 . Stochastic heating of small grains leads to a wide distribution of dust temperatures. This supports the idea that large amounts (∼0.1 M⊙ ) of cold dust ( T ∼ 40 K) can be present in SNRs, without being in conflict with the observed infrared emission. 相似文献
68.
Raffaella De Luca Domenico Miriello Alessandra Pecci Salvador Domínguez‐Bella Dario Bernal‐Casasola Daniela Cottica Andrea Bloise Gino Mirocle Crisci 《Geoarchaeology》2015,30(4):330-351
This paper presents the results of the compositional study of 29 samples of mortar from the so‐called “Garum Shop” (I, 12, 8) at Pompeii in Southern Italy. The characterization of the samples yielded information on the raw materials used in the mixtures, the production technology of mortars, and the building phases. It was carried out through polarized optical microscopy, X‐ray powder diffraction, X‐ray fluorescence, microanalysis energy‐dispersive X‐ray spectroscopic microanalysis, and image analysis through the JMicroVision software. The resultant data show great compositional homogeneity among the samples, suggesting the presence of a principal construction phase, probably associated with the first phase of the house. Apart from this main construction phase, there are some samples that show differences related either to their different function or to the fact that they come from different construction phases or restoration works. The raw materials used are related to the geology of the area and are fully compatible with the pyroclastic deposits of Vesuvius. 相似文献