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The Friuli Venezia Giulia Accelerometric Network: RAF
No full textThe first stations of the FriuliVenezia Giulia (NE Italy)AccelerometricNetwork
(Rete Accelerometrica del Friuli Venezia Giulia—RAF) were installed by the Department of
Earth Sciences, University of Trieste, in the early nineties in the framework of international
scientific projects. Today RAF is configured, taking in to account also other network stations
operating in Italy as well as in Austria and Slovenia, to record accelerations at several
important sites in the seismic area of Friuli Venezia Giulia and near its borders with Slovenia
and Austria. This allows an immediate estimate of peak ground acceleration as well as a
first evaluation of possible damages. In the year 2000, DST and the Friuli Venezia Giulia
Direction of the Civil Defence signed an agreement for the RAF management and its use
for civil defence purposes, like the prompt estimate of the damage level after an earthquake
occurrence, the emergency management, the reconstruction planning, and the validation and
updating of seismic hazard maps. Moreover, RAF recordings are used also for prevention
purposes by the civil defence. This is performed with the computation of real time shake
maps, possible ground-shaking scenarios, studies of the physics of the seismic source, site
effects estimates and microzonation analyses
Real-time generation of Shake Maps in the Southeastern Alps.
No full textThe aim of this study is the real-time generation of ShakeMaps in the
southeastern Alps area. The ShakeMap software has been adapted to the southeastern
Alps region and implemented to obtain a stable interface with the Antelope acquisition
system in order to extract the ground-motion parameters from the waveforms and to
generate ShakeMaps within 5 min of the earthquake occurrence. To evaluate the influence
of the station density, synthetic seismograms are computed for the Bovec
(northwest Slovenia) 2004 earthquake, and various ShakeMaps are generated by varying
the grid size of the simulated recording stations. The results indicate that a dense
and uniform spatial distribution of stations in the field is essential to produce accurate
ShakeMaps, and the present density of stations in central Friuli is sufficient for a reliable
estimate of the extent of the area of strongest shaking. The related maps are generated
in real time or quasi-real time using the region-specific ground-motion
predictive equations and empirical relations that predict the macroseismic intensity
from the recorded ground motion. The model is validated by comparison between
observed data and ShakeMap results for both weak motions (Claut 2007 earthquake)
and strong motions (Bovec 1998 earthquake)
Finite-fault parameters of the September 1976 M>5 aftershocks in Friuli (NE Italy)
No full textOn September 1976 four strong aftershocks with M>5 occurred in the Friuli area (NE Italy) causing more damage with respect to that caused by the M6.4 mainshock that occurred on May 6, 1976. Although many studies have been published on the 1976 Friuli seismic sequence, only recently have finite-fault models based on geological considerations (Galadini et al., 2005; Burrato et al., 2008) been proposed for these aftershocks. The aim of our study is to model the September 1976 seismic sources as finite faults by computing
finite-fault synthetic seismograms for several possible proposed fault models and nucleation locations. The seismicity distribution following each of the four events gives us some further information about the areal extent of the related fault and its rupture propagation. About 9000 synthetic seismograms are computed for all the tested fault models adopting the reflectivity technique for an upper cutoff frequency of 1 Hz. A “trial and error” procedure is used to find the best fit between the recorded and computed peak ground acceleration
derived from signals filtered at 1 Hz, that identifies the final models. These are selected also on the basis of the existing knowledge of fault traces in the area. The four best-fit models seem to be well related to
the main Barcis-Staro Selo fault system, their spatial–temporal sequence evidencing an overall progressive East-to-West migration of the seismic activity related to the 1976 sequence
ShakeMaps for Three Relevant Earthquakes in the Southeastern Alps: Comparison Between Instrumental and Observed Intensities
No full textWe test a recently developed ShakeMap model for the Friuli Venezia Giulia (NE Italy) region (Moratto et al.,
2009) by comparing the macroseismic observations, related to three past earthquakes (Cansiglio 1936, Friuli
1976 and Bovec-Krn 1998) which occurred in this region, with the instrumental intensities obtained from the
ShakeMaps, and based on synthetic seismograms computed from available source models of these events.
Because a comparison requires that the simulation resembles as close as possible the real situation,
ShakeMaps are computed from synthetics calculated at receivers placed at the sites where the recording
instruments are already operative and at the sites where the instruments are going to be installed in the near
future. Since the available instrumental recordings are very few, the resulting instrumental intensity maps are
compared with the macroseismic observations wherever the latter are available. We make use of various
relationships between the ground motion parameters and the macroseismic intensity during the comparison.
The best results are obtained when the macroseismic intensities (I≤VII) are estimated using the relationship
proposed by Faenza and Michelini (2010)
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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