1,662 research outputs found
Assessing the vulnerability of buildings to tsunami in Sydney
Australia is vulnerable to the impacts of tsunamis and exposure along the SE coast of New South Wales is especially high. Significantly, this is the same area reported to have been affected by repeated large magnitude tsunamis during the Holocene. Efforts are under way to complete probabilistic risk assessments for the region but local government planners and emergency risk managers need information now about building vulnerability in order to develop appropriate risk management strategies. We use the newly revised PTVA-3 Model (Dall'Osso et al., 2009) to assess the relative vulnerability of buildings to damage from a "worst case tsunami" defined by our latest understanding of regional risk – something never before undertaken in Australia. We present selected results from an investigation of building vulnerability within the local government area of Manly – an iconic coastal area of Sydney. We show that a significant proportion of buildings (in particular, residential structures) are classified as having "High" and "Very High" Relative Vulnerability Index scores. Furthermore, other important buildings (e.g., schools, nursing homes and transport structures) are also vulnerable to damage. Our results have serious implications for immediate emergency risk management, longer-term land-use zoning and development, and building design and construction standards. Based on the work undertaken here, we recommend further detailed assessment of the vulnerability of coastal buildings in at risk areas, development of appropriate risk management strategies and a detailed program of community engagement to increase overall resilience
Corrigendum to "A revised (PTVA) model for assessing the vulnerability of buildings to tsunami damage" published in Nat. Hazards Earth Syst. Sci., 9, 1557–1565, 2009"
No abstract available
Applying and validating the PTVA-3 Model at the Aeolian Islands, Italy: assessment of the vulnerability of buildings to tsunamis
The volcanic archipelago of the Aeolian Islands (Sicily, Italy) is included on the UNESCO World Heritage list and is visited by more than 200 000 tourists per year. Due to its geological characteristics, the risk related to volcanic and seismic activity is particularly high. Since 1916 the archipelago has been hit by eight local tsunamis. The most recent and intense of these events happened on 30 December 2002. It was triggered by two successive landslides along the north-western side of the Stromboli volcano (Sciara del Fuoco), which poured approximately 2–3&times;10<sup>7</sup> m<sup>3</sup> of rocks and debris into the Tyrrhenian Sea. The waves impacted across the whole archipelago, but most of the damage to buildings and infrastructures occurred on the islands of Stromboli (maximum run-up 11 m) and Panarea. <br><br> The aim of this study is to assess the vulnerability of buildings to damage from tsunamis located within the same area inundated by the 2002 event. The assessment is carried out by using the PTVA-3 Model (Papathoma Tsunami Vulnerability Assessment, version 3). The PTVA-3 Model calculates a Relative Vulnerability Index (RVI) for every building, based on a set of selected physical and structural attributes. Run-up values within the area inundated by the 2002 tsunami were measured and mapped by the Istituto Italiano di Geofisica e Vulcanologia (INGV) and the University of Bologna during field surveys in January 2003. Results of the assessment show that if the same tsunami were to occur today, 54 buildings would be affected in Stromboli, and 5 in Panarea. The overall vulnerability level obtained in this analysis for Stromboli and Panarea are "average"/"low" and "very low", respectively. Nonetheless, 14 buildings in Stromboli are classified as having a "high" or "average" vulnerability. For some buildings, we were able to validate the RVI scores calculated by the PTVA-3 Model through a qualitative comparison with photographs taken by INGV and the University of Bologna during the post-tsunami survey. With the exception of a single structure, which is partially covered by a coastal dune on the seaward side, we found a good degree of accuracy between the PTVA-3 Model forecast assessments and the actual degree of damage experienced by buildings. This validation of the model increases our confidence in its predictive capability. Given the high tsunami risk for the archipelago, our results provide a framework for prioritising investments in prevention measures and addressing the most relevant vulnerability issues of the built environment, particularly on the island of Stromboli
Corrigendum to "Applying and validating the PTVA-3 Model at the Aeolian Islands, Italy: assessment of the vulnerability of buildings to tsunamis" published in Nat. Hazards Earth Syst. Sci., 10, 1547–1562, 2010
F. Dall'Osso1,2,4, A. Maramai3, L. Graziani3, B. Brizuela3, A. Cavalletti2,4, M. Gonella2,4, and S. Tinti5 1CIRSA, Interdepartmental Centre for Environmental Sciences Research, University of Bologna, via S. Alberto 163, 48100 Ravenna, Italy 2IDRA, Environmental Research Institute, via Kennedy 37, 44100 Ferrara, Italy 3INGV, Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Roma, Italy 4Med Ingegneria S.r.l., Environmental Engineering, via P. Zangheri 16, 48124 Ravenna, Italy 5University of Bologna, Department of Physics, Viale Carlo Berti Pichat 8, 40127 Bologna, Ital
Analytical parametrization and shape classification of anomalous HH production in the EFT approach
20 pages, 10 figures, LHC Higgs Cross Section Working Group report http://cds.cern.ch/record/2199287In this document we study the effect of anomalous Higgs boson couplings on non-resonant pair production of Higgs bosons () at the LHC. We explore the space of the five parameters , , , , and in terms of the corresponding kinematics of the final state, and describe a partition of the space into a limited number of regions featuring similar phenomenology in the kinematics of final state. We call clusters the sets of points belonging to the same region; to each cluster corresponds a representative point which we call a benchmark. We discuss a possible technique to estimate the sensitivity of an experimental search to the kinematical differences between the phenomenology of the benchmark points and the rest of the parameter space contained in the corresponding cluster. We also provide an analytical parametrization of the cross-section modifications that the variation of anomalous couplings produces with respect to standard model production along with a recipe to translate the results into other parameter-space bases. Finally, we provide a preliminary analysis of variations in the topology of the final state within each region based on recent LHC results
The 2008 October Swift detection of X-ray bursts/outburst from the transient SGR-like AXP 1E 1547.0-5408
We report on the detailed study of the 2008 October outburst from the
anomalous X-ray pulsar (AXP) 1E 1547.0-5408 discovered through the Swift/Burst
Alert Telescope (BAT) detection of SGR-like short X-ray bursts on 2008 October
3. The Swift/X-ray Telescope (XRT) started observing the source after less than
100 s since the BAT trigger, when the flux (about 6E-11 erg/cm^2/s in the 2-10
keV range) was >50 times higher than its quiescent level. Swift monitored the
outbursting activity of 1E 1547.0-5408 on a daily basis for approximately three
weeks. This strategy allowed us to find a phase-coherent solution for the
source pulsations after the burst, which, besides period and period derivative,
requires a positive Period second derivative term (spin-down increase). The
time evolution of the pulse shape is complex and variable, with the pulsed
fraction increasing from 20% to 50% within the Swift observational window. The
XRT spectra can be fitted well by means of a single component, either a
power-law (PL) or a blackbody (BB). During the very initial phases of the
outburst the spectrum is hard, with a PL photon index about 2 (or kT about 1.4
keV) which steepens to about 4 (or kT about 0.8 keV) within one day from the
BAT trigger, though the two components are likely present simultaneously during
the first day spectra. An INTEGRAL observation carried out five days after the
trigger provided an upper limit of about 2E-11 erg/cm^2/s to the emission of 1E
1547.0-5408 in the 18-60 keV band.Comment: 10 pages, 2 tables, 6 figures; accepted for publication in MNRA
A semi-coherent generalization of the 5-vector method to search for continuous gravitational waves
The emission of continuous gravitational waves (CWs), with duration much
longer than the typical data taking runs, is expected from several sources,
notably spinning neutron stars, asymmetric with respect to their rotation axis
and more exotic sources, like ultra-light scalar boson clouds formed around
Kerr black holes and sub-solar mass primordial binary black holes. Unless the
signal time evolution is well predicted and its relevant parameters accurately
known, the search for CWs is typically based on semi-coherent methods, where
the full data set is divided in shorter chunks of given duration, which are
properly processed, and then incoherently combined. In this paper we present a
semi-coherent method, in which the so-called \textit{5-vector} statistics is
computed for the various data segments and then summed after the removal of the
Earth Doppler modulation and signal intrinsic spin-down. The method can work
with segment duration of several days, thanks to a double stage procedure in
which an initial rough correction of the Doppler and spin-down is followed by a
refined step in which the residual variations are removed. This method can be
efficiently applied for directed searches, where the source position is known
to a good level of accuracy, and in the candidate follow-up stage of
wide-parameter space searches.Comment: 16 pages, 12 figure
Transient Phenomena in Anomalous X-ray Pulsars
In 2003 a previously unpulsed Einstein and ROSAT source cataloged as soft and
dim (Lx of few 10^33 ergs) thermal emitting object, namely XTE J1810-197, was
identified as the first unambiguous transient Anomalous X-ray Pulsar. Two years
later this source was also found to be a bright highly polarized transient
radio pulsar, a unique property among both AXPs and radio pulsars. In September
2006 the Swift Burst Alert Telescope (BAT) detected an intense burst from the
candidate AXP CXOU J164710.2-455216, which entered in an outburst state
reaching a peak emission of at least a factor of 300 higher than quiescence.
Here, we briefly outline the recent results concerning the outburst phenomena
observed in these two AXPs. In particular, XTE J1810-197 has probed to be a
unique laboratory to monitor the timing and spectral properties of a
cooling/fading AXP, while new important information have been inferred from
X-ray and radio band simultaneous observations. CXOU J164710.2-455216 has been
monitored in X-rays and radio bands since the very beginning of its outbursting
state allowing us to cover the first phases of the outburst and to study the
timing and spectral behavior during the first months.Comment: 5 pages, 3 figures, proceedings of the conference "40 Years of
Pulsars, Millisecond Pulsars, Magnetars and More", Montreal, August 12-17
2007. To be published by AIP
The supergiant fast X-ray transient IGRJ18483-0311 in quiescence: XMM-Newton, Swift, and Chandra observations
IGR J18483-0311 was discovered with INTEGRAL in 2003 and later classified as
a supergiant fast X-ray transient. It was observed in outburst many times, but
its quiescent state is still poorly known. Here we present the results of
XMM-Newton, Swift, and Chandra observations of IGRJ18483-0311. These data
improved the X-ray position of the source, and provided new information on the
timing and spectral properties of IGR J18483-0311 in quiescence. We report the
detection of pulsations in the quiescent X-ray emission of this source, and
give for the first time a measurement of the spin-period derivative of this
source. In IGRJ18483-0311 the measured spin-period derivative of
-(1.3+-0.3)x10^(-9) s/s likely results from light travel time effects in the
binary. We compare the most recent observational results of IGRJ18483-0311 and
SAXJ1818.6-1703, the two supergiant fast X-ray transients for which a similar
orbital period has been measured.Comment: Accepted for publication in MNRA
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