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Sample records for monte aquila fault

  1. Multi-scale electromagnetic imaging of the Monte Aquila Fault (Agri Valley, Southern Italy)

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    Giocoli, Alessandro; Piscitelli, Sabatino; Romano, Gerardo; Balasco, Marianna; Lapenna, Vincenzo; Siniscalchi, Agata

    2010-05-01

    The Agri Valley is a NW-SE trending intermontane basin formed during the Quaternary times along the axial zone of the Southern Apennines thrust belt chain. This basin is about 30 Km long and 12 Km wide and is filled by Quaternary continental deposits, which cover down-thrown pre-Quaternary rocks of the Apennines chain. The Agri Valley was hit by the M 7.0, 1857 Basilicata earthquake (Branno et al., 1985), whose macroseismic field covered a wide sector of the Southern Apennines chain. The latest indications of Late Quaternary faulting processes in Agri Valley were reported in Maschio et al., (2005), which documented a unknown NE-dipping normal fault thanks to the finding of small-scale morphological features of recent tectonic activity. The identified structure was termed Monte Aquila Fault (MAF) and corresponds to the southern strand of the NW-SE trending Monti della Maddalena Fault System (Maschio et al., 2005; Burrato and Valensise, 2007). The NE-dipping MAF consists of a main northern segment, about 10 Km long, and two smaller segments with cumulate length of ~10 Km, thus bringing the total length to ~20 Km. The three segments are arranged in a right-stepping en-echelon pattern and are characterized by subtle geomorphic features. In order to provide more detailed and accurate information about the MAF, a strategy based on the application of complementary investigation tools was employed. In particular, multi-scale electromagnetic investigation, including Electrical Resistivity Tomography (ERT), Ground Penetrating Radar (GPR) and Magnetotelluric (MT) methods, was used to image the MAF from near-surface to several hundred metres depth. Large-scale MT investigation proved to be useful in detecting the MAF location down to several hundred meters depth, but it didn't show any shallow evidence about MAF. Conversely, ERT and GPR surveys evidenced signatures of normal-faulting activity at shallow depth (e.g., back-tilting of the bedrock, colluvial wedges, etc.). In

  2. Source Parameters of the 2009 L'Aquila Fault Earthquakes (Italy)

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    Tinti, E.; Scognamiglio, L.; Piccinini, D.; Chiaraluce, L.; Valoroso, L.; Cocco, M.

    2014-12-01

    The 2009 L'Aquila main shock (6th of April, Mw6.1) is one of the best-recorded normal faulting earthquakes with a distinctive foreshock-aftershock sequence. The seismic sequence activated an ~50-km-long, N133°E-trending fault system composed of two major right-stepping en echelon segments: the L'Aquila fault (AF) and the Campotosto fault. We focus our analysis only on the volume containing the high-angle AF segment where the whole foreshock sequence clustered around the nucleation patch together with numerous repeating earthquakes. Analyzing the seismograms of the events that occurred within 6 km (±3) from the AF plane we discuss the complex nucleation and rupture process characterizing the 2009 L'Aquila earthquake together with the inferred heterogeneous distribution of the material/mechanical rock properties, seismicity pattern and coseismic slip, showing how different competing mechanisms control the initial stage of rupture and the dynamic rupture propagation. We compute source parameters (i.e., stress drop, moment magnitude and corner frequency) of foreshocks and aftershocks to investigate the spatial-temporal pattern of fault zone heterogeneities. Source spectra at each station are inferred by using the multi-taper technique and corrected for attenuation; therefore corner frequency is inferred by using the Snoke's relation. Outputs were compared to those we obtained by a multi-window-spectral-ratio technique (MWSR) computing the fit of stacked spectral ratios. Further, we discuss the results with those found in the literature. Ml versus Mw relation is inferred for this dataset. Foreshocks and aftershocks nucleated in the same fault portion do not show any difference in source parameters.

  3. Spatio-Temporal Changes Recorded by an On-fault Seismological Station During the L' Aquila Earthquakes.

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    Calderoni, G.; Rovelli, A.; Di Giovambattista, R.

    2014-12-01

    A broad band station (FAGN) installed on a segment of the fault system that generated the April 2009 L'Aquila earthquakes shows much larger ground motions compared to nearby stations. Calderoni et al. (2010) observed that the strongest amplifications were observed for tightly clustered aftershocks aligned with the fault dip beneath FAGN thus indicating a fault-guided effect. In a second paper, Calderoni et al. (2012) found that the most efficient trapped waves at FAGN were clustered at the northwestern and southeastern tips of the fault plane responsible for the MW 6.1, L'Aquila earthquake. In this study we examine temporal variations of the fault zone properties analyzing the fault-trapped waves generated by 19 repeaters located at the northwestern tip. Fault-zone trapped waves are particularly suited for this analysis as their amplitude and frequency content depend on the geometry and elastic and anelastic parameters of the fault zone. We observe that efficiency of trapped waves (estimated through spectral ratio amplitudes) sudden increased immediately following the Mw 4.1, March 30 largest foreshock. This increase persists until the occurrence of the mainshock, then amplitude decreases to the background after a hundred of days. Material properties are the most obvious candidates of temporal changes but the concomitant role of rupture directivity was also checked, thanks to the precise information on along-strike directivity of that fault inferred by Calderoni et al. (2014).

  4. The 2009MW 6.1 L'Aquila fault system imaged by 64k earthquake locations

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    Valoroso, Luisa

    2016-03-01

    On April 6 2009, a MW 6.1 normal-faulting earthquake struck the axial area of the Abruzzo region in central Italy. We investigate the complex architecture and mechanics of the activated fault system by using 64k high-resolution foreshock and aftershock locations. The fault system is composed by two major SW dipping segments forming an en-echelon NW trending system about 50km long: the high-angle L'Aquila fault and the listric Campotosto fault, located in the first 10km depth. From the beginning of 2009, foreshocks activated the deepest portion of the mainshock fault. A week before the MW 6.1 event, the largest (MW 4.0) foreshock triggered seismicity migration along a minor off-fault segment. Seismicity jumped back to the main plane a few hours before the mainshock. High-precision locations allowed us to peer into the fault zone showing complex geological structures from the metre to the kilometre scale, analogous to those observed by field studies and seismic profiles. Also, we were able to investigate important aspects of earthquakes nucleation and propagation through the upper crust in carbonate-bearing rocks such as: the role of fluids in normal-faulting earthquakes; how crustal faults terminate at depths; the key role of fault zone structure in the earthquake rupture evolution processes.

  5. A reversed hierarchy of active normal faults: the 6 April 2009, Mw 6.3, L'Aquila earthquake (Italy

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    L. Bonini

    2013-01-01

    Full Text Available Understanding the relationship between seismogenic slip at depth and surface deformation is fundamental in any seismic hazard analysis because the assessment of the earthquake potential of large continental faults relies largely on field investigations. The well-documented 6 April 2009, Mw 6.3, L'Aquila earthquake affords a unique opportunity to explore the relationships between the activity of the deep source and its surface evidence. We used available high-resolution geologic, geodetic and seismological data aided by analogue modeling to reconstruct the geometry of the seismogenic rupture in relation with surface and sub-surface faults. We contend that the earthquake was caused by a blind fault, controlled at depth by pre-existing discontinuities and expressed at the surface by pseudo-primary breaks resulting from coseismic crustal bending. Finally, we propose a scheme for hierarchizing normal faults that explains all surface occurrences related to blind faulting in the frame of a single, mechanically coherent, interpretative model. Failure to appreciate such complexity may result in severe over– or under-estimation of the local seismogenic potential.

  6. The 2009 April 6, Mw 6.3, L'Aquila (central Italy) earthquake: finite-fault effects on intensity data

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    Ameri, G.; Bindi, D.; Pacor, F.; F. Galadini

    2011-01-01

    We analyse the spatial distribution of the intensity data points surveyed after the Mw 6.3, 2009 L’Aquila (central Italy) earthquake, with the aim to recognize and quantify finite-fault and directivity effects. The study is based on the analysis of the residuals, evaluated with respect to attenuation-with-distance models, calibrated for L’Aquila earthquake. We apply a non-parametric approach considering both the epicentral and the rupture distance, which accounts for the finite extension of t...

  7. Monitoring of crustal seismic velocity variations in the L'Aquila fault zone inferred from noise cross-correlation

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    Soldati, Gaia; Zaccarelli, Lucia; Faenza, Licia; Michelini, Alberto

    2015-07-01

    The relative seismic velocity variations possibly associated to large earthquakes can be readily monitored via cross-correlation of seismic noise. In a recently published study, more than 2 yr of continuous seismic records have been analysed from three stations surrounding the epicentre of the 2009 April 6, Mw 6.1 L'Aquila earthquake, observing a clear decrease of seismic velocities likely corresponding to the co-seismic shaking. Here, we extend the analysis in space, including seismic stations within a radius of 60 km from the main shock epicentre, and in time, collecting 5 yr of data for the six stations within 40 km of it. Our aim is to investigate how far the crustal damage is visible through this technique, and to detect a potential post-seismic recovery of velocity variations. We find that the co-seismic drop in velocity variations extends up to 40 km from the epicentre, with spatial distribution (maximum around the fault and in the north-east direction from it) in agreement with the horizontal co-seismic displacement detected by global positioning system (GPS). In the first few months after L'Aquila earthquake, the crust's perturbation in terms of velocity variations displays a very unstable behaviour, followed by a slow linear recovery towards pre-earthquake conditions; by almost 4 yr after the event, the co-seismic drop of seismic velocity is not yet fully recovered. The strong oscillations of the velocity changes in the first months after the earthquake prevent to detect the fast exponential recovery seen by GPS data. A test of differently parametrized fitting curves demonstrate that the post-seismic recovery is best explained by a sum of a logarithmic and a linear term, suggesting that processes like viscoelastic relaxation, frictional afterlip and poroelastic rebound may be acting concurrently.

  8. Fault Geometry and Active Stress from Earthquakes and Field Geology Data Analysis: The Colfiorito 1997 and L'Aquila 2009 Cases (Central Italy)

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    Ferrarini, F.; Lavecchia, G.; de Nardis, R.; Brozzetti, F.

    2015-05-01

    The fault segmentation pattern and the regional stress tensor acting since the Early Quaternary in the intra-Apennine area of central Italy was constrained by integrating two large geological and seismological fault-slip data sets collected for the areas struck by the two most energetic seismic sequences of the last 15 years (Colfiorito 1997, M w 6.0 and L'Aquila 2009, M w 6.1). The integrated analysis of the earthquake fault association and the reconstruction of the 3D shape of the seismogenic sources were exploited to identify homogeneous seismogenic volumes associated with subsets of geological and focal mechanism data. The independent analysis of geological and seismological data allowed us to observe and highlight similarities between the attitude of the long-term (e.g., Quaternary) and the instantaneous present-day (seismogenic) extensional deformations and to reveal their substantial coaxiality. Coherently, with the results from the kinematic analysis, the stress field inversion also noted a prevailing tensional seismotectonic regime associated with a subhorizontal, NE-SW, minimum stress axis. A minor, very local, and shallow (L'Aquila area. These results do not agree with those indicating Quaternary regional strike-slip regimes or wide areas characterized by strike-slip deformation during the Colfiorito and L'Aquila seismic sequences.

  9. Transient anomaly in fault zone-trapped waves during the preparatory phase of the 6 April 2009, Mw 6.3 L'Aquila earthquake

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    Calderoni, Giovanna; Rovelli, Antonio; Di Giovambattista, Rita

    2015-03-01

    Fault zone-trapped waves generated by repeating earthquakes of the 2009 L'Aquila seismic sequence show a sudden, up to 100% increase of spectral amplitudes 7 days before the main shock. The jump occurs 10 to 20 h after the ML 4.1, 30 March 2009 largest foreshock. The amplitude increase is accompanied by a loss of waveform coherence in the fault-trapped wave train. Other geophysical and seismological parameters are known to have shown a sudden change after the 30 March foreshock. The concomitance of a consistent change in the fault zone-trapped waves leads us to interpret our observation as due to a sudden temporal variation of the velocity contrast between the fault damage zone and hosting rocks in the focal volume. Fault zone-trapped waves thus provide a refined time resolution for changes occurring near the rupture nucleation, with the indication of a strong variation in 1 day.

  10. 3D Faulting Numerical Model Related To 2009 L'Aquila Earthquake Based On DInSAR Observations

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    Castaldo, Raffaele; Tizzani, Pietro; Solaro, Giuseppe; Pepe, Susi; Lanari, Riccardo

    2014-05-01

    We investigate the surface displacements in the area affected by the April 6, 2009 L'Aquila earthquake (Central Italy) through an advanced 3D numerical modeling approach, by exploiting DInSAR deformation velocity maps based on ENVISAT (Ascending and Descending orbits) and COSMO-SkyMed data (Ascending orbit). We benefited from the available geological and geophysical information to investigate the impact of known buried structures on the modulation of the observed ground deformation field; in this context we implemented the a priori information in a Finite Element (FE) Environment considering a structural mechanical physical approach. The performed analysis demonstrate that the displacement pattern associated with the Mw 6.3 main-shock event is consistent with the activation of several fault segments of the Paganica fault. In particular, we analyzed the seismic events in a structural mechanical context under the plane stress mode approximation to solve for the retrieved displacements. We defined the sub-domain setting of the 3D FEM model using the information derived from the CROOP M-15 seismic line. We assumed stationarity and linear elasticity of the involved materials by considering a solution of classical equilibrium mechanical equations. We evolved our model through two stages: the model compacted under the weight of the rock successions (gravity loading) until it reached a stable equilibrium. At the second stage (co-seismic), where the stresses were released through a slip along the faults, by using an optimization procedure we retrieved: (i) the active seismogenic structures responsible for the observed ground deformation, (ii) the effects of the different mechanical constraints on the ground deformation pattern and (iii) the spatial distribution of the retrieved stress field. We evaluated the boundary setting best fit configuration responsible for the observed ground deformation. To this aim, we first generated several forward structural mechanical models

  11. New paleoseismic data across the Mt. Marine Fault between the 2016 Amatrice and 2009 L’Aquila seismic sequences (central Apennines

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    Marco Moro

    2016-11-01

    Full Text Available Paleoseismological investigations have been carried out along the Mt. Marine normal fault, a probable source of the February 2, 1703 (Me=6.7 earthquake. The fault affects the area between the 2016 Amatrice and 2009 L’Aquila seismic sequences. Paleoseismological analysis provides data which corroborate previous studies, highlighting the occurrence of 5 events of surface faulting after the 6th–5th millenium B.C., the most recent of which is probably the 2 February 1703 earthquake. A minimum displacement per event of about 0.35 m has been measured. The occurrence of a minimum four faulting events within the last 7,000 years suggests a maximum 1,700 years recurrence interval.

  12. Gradual Fault Weakening with Seismic Slip: Inferences from the Seismic Sequences of L'Aquila, 2009, and Northridge, 1994

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    Malagnini, Luca; Munafo', Irene; Cocco, Massimo; Nielsen, Stefan; Mayeda, Kevin; Boschi, Enzo

    2014-10-01

    We estimate seismological fracture energies from two subsets of events selected from the seismic sequences of L'Aquila (2009), and Northridge (1994): 57 and 16 selected events, respectively, including the main shocks. Following Abercrombie and Rice (Geophys J Int 162: 406-424, 2005), we postulate that fracture energy (G) represents the post-failure integral of the dynamic weakening curve, which is described by the evolution of shear traction as a function of slip. Following a direct-wave approach, we compute mainshock-/aftershock-source spectral ratios, and analyze them using the approach proposed by Malagnini et al. (Pure Appl. Geophys., this issue, 2014) to infer corner frequencies and seismic moment. Our estimates of source parameters (including fracture energies) are based on best-fit grid-searches performed over empirical source spectral ratios. We quantify the source scaling of spectra from small and large earthquakes by using the MDAC formulation of W alter and Taylor (A revised Magnitude and Distance Amplitude Correction (MDAC2) procedure for regional seismic discriminants, 2001). The source parameters presented in this paper must be considered as point-source estimates representing averages calculated over specific ruptured portions of the fault area. In order to constrain the scaling of fracture energy with coseismic slip, we investigate two different slip-weakening functions to model the shear traction as a function of slip: (i) a power law, as suggested by Abercrombie and Rice (Geophys J Int 162: 406-424, 2005), and (ii) an exponential decay. Our results show that the exponential decay of stress on the fault allows a good fit between measured and predicted fracture energies, both for the main events and for their aftershocks, regardless of the significant differences in the energy budgets between the large (main) and small earthquakes (aftershocks). Using the power-law slip-weakening function would lead us to a very different situation: in our two

  13. April 7, 2009, Mw 5.5 aftershock of the L'Aquila earthquake: seismogenic fault geometry and its implication for the central Apennines active extensional tectonics (Italy).

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    Adinolfi, Guido Maria; Lavecchia, Giusy; De Matteis, Raffaella; Nardis Rita, De; Francesco, Brozzetti; Federica, Ferrarini; Zollo, Aldo

    2015-04-01

    On April 6, 2009 (at 01:32 UTC) a Mw 6.3 earthquake hit the town of L'Aquila (central Italy) and surrounding villages causing fatalities and severe damage in the area. After few days, a nearly 40-km-long extensional fault system was activated generating both northward and southward seismicity migration along the NW-SE trending sector of central Apennines. During the intense aftershocks sequence, different sesmogenic sources with a distinct geometry, size and the degree of involvement were reactivated. Among the relevant aftershocks with Mw 5.0 to 5.5, the largest one occurred on April 7 (at 17:47 UTC), 9 km SE-ward of the mainshock involving a source seated at much greater depths (~14 km). Despite the enormous number of studies of the 2009 L'Aquila earthquake, mainly focused on the various geological and seismological aspects of the main Paganica source, the April 7 strongest aftershock (Mw 5.5) has not yet been deeply investigated. Consistent geometric and kinematic correlations between the geological and seismological data about this seismogenic source are missing. There are still open questions concerning its unresolved geometry and the unknown style of the central Apennines structure activated at greater depths during the 2009 L'Aquila seismic sequence. Furthermore, some authors (Lavecchia et al., 2012) have supposed that the April 7, 2009 aftershock (Mw 5.5) occurred onto an high dip segment (~50°) of an east-dipping extensional basal detachment with a potential surface expression outcropping in the area of the eastern Sabina-Simbruini Mts. In this work we propose a seismological analysis of the April 7, 2009 aftershock (Mw 5.5) rupture process. In order to define the unresolved source geometry, we computed the focal mechanism through the time domain, moment tensor full waveform inversion (Dreger and Helmberger, 1993). Also, we estimated the apparent source time functions (ASTFs) by deconvolution of the impulse response of the medium from the recorded data

  14. Morphotectonic analysis of the long-term surface expression of the 2009 L'Aquila earthquake fault (Central Italy) using airborne LiDAR data

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    Civico, Riccardo; Pucci, Stefano; De Martini, Paolo Marco; Pantosti, Daniela

    2015-03-01

    In this paper we present a morphotectonic study of the Paganica-San Demetrio fault system (PSDFS) responsible for the Mw6.1 April 6, 2009 earthquake (L'Aquila, Central Italy). The discrepancy observed between the length of the seismologic-geodetic modeled fault, the limited size of the primary coseismic surface ruptures and the significant morphological expression of the PSDFS stimulated a debate about the maximum rupture length of the PSDFS and its capability to generate larger magnitude events. To image the PSDFS long-term morphological expression and define its surface geometrical arrangement (length, number of fault splays and boundaries), we took advantage of a high-resolution airborne LiDAR dataset. LiDAR topography substantially increased our confidence in detecting even subtle tectonic-controlled morphologies. We define the PSDFS as a ~ 19 km-long fault system that displays a complex structural setting characterized by two different sectors: 1) the Paganica sector to the NW, with a narrow deformation zone, and 2) the San Demetrio sector to SE, where the strain is accommodated by several fault-splays dissecting a wider Quaternary basin. We also defined a first-order hierarchy among the numerous fault splays across the PSDFS. The long-term geomorphic expression of the PSDFS suggests that it ruptured also involving the whole 19 km-long structure besides rupturing only small sections, as it occurred in 2009. This suggests a variable slip behavior. Empirical relations applied to this hypothesis allow up to M 6.6 earthquakes along the PSDFS. These results have a critical impact on the seismic hazard assessment of the area when compared with a M 6.1 event as the 2009.

  15. Morphotectonic, Quaternary and Structural Geology Analyses of the Shallow Geometry of the Mw 6.1, 2009 L'Aquila Earthquake Fault (central Italy): A Missed Opportunity for Surface Faulting Prevention.

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    Pucci, S.; Villani, F.; Civico, R.; Pantosti, D.; Smedile, A.; De Martini, P. M.; Di Naccio, D.; Gueli, A.

    2014-12-01

    The surface-rupturing 2009 L'Aquila earthquake evidenced the limited knowledge of active faults in the Middle Aterno Valley area. Gaps in detailed mapping of Quaternary deposits and tectonic landforms did not trigger researches on active faults, but after the tragic event. We present a morphotectonic study of geometry and evolution of the activated fault system (Paganica-San Demetrio, PSDFS). The LIDAR analysis and field survey yield to a new geological and structural map of the area with an unprecedented detail for the Quaternary deposits. It shows an alluvial depositional system prograding and migrating due to fault system evolution. The normal faults offset both the Quaternary deposits and the bedrock. The structural analysis allows us to recognize two fault systems: (A) NNE- and WNW-trending conjugate extensional system overprinting a strike-slip kinematics and (B) dip-slip NW-trending system. Crosscut relationship suggests that the activity of system B prevails, since Early Pleistocene, on system A, which earlier may have controlled a differently shaped basin. System B is the main responsible for the present-day compound outline of the Middle Aterno Valley, while system A major splays now act as segment boundaries. The long-term expression of B results in prominent fault scarps offsetting Quaternary deposits, dissecting erosional and depositional flat landforms. We retrieved detailed morphologic throws along fault scarps and we dated landforms by 14C, OSL (Optically Stimulated Luminescence), CRN (Cosmogenic Radionuclide) and tephra chronology. We show the persistent role of extensional faulting in dominating Quaternary landform evolution and we estimate slip-rate of the PSDFS at different time-scales. The results support repeated activity of PSDFS for ~20 km total length, thus implying M6.6 maximum expected earthquake. Such an approach should have been applied beforehand for the actual hazard estimation, to trigger, early enough, the adoption of precautionary

  16. Fault Risk Assessment of Underwater Vehicle Steering System Based on Virtual Prototyping and Monte Carlo Simulation

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    He Deyu

    2016-09-01

    Full Text Available Assessing the risks of steering system faults in underwater vehicles is a human-machine-environment (HME systematic safety field that studies faults in the steering system itself, the driver’s human reliability (HR and various environmental conditions. This paper proposed a fault risk assessment method for an underwater vehicle steering system based on virtual prototyping and Monte Carlo simulation. A virtual steering system prototype was established and validated to rectify a lack of historic fault data. Fault injection and simulation were conducted to acquire fault simulation data. A Monte Carlo simulation was adopted that integrated randomness due to the human operator and environment. Randomness and uncertainty of the human, machine and environment were integrated in the method to obtain a probabilistic risk indicator. To verify the proposed method, a case of stuck rudder fault (SRF risk assessment was studied. This method may provide a novel solution for fault risk assessment of a vehicle or other general HME system.

  17. LAqui-core, a 150 m deep borehole into the depocenter of the basin controlled by the 2009 Mw=6.1 L'Aquila earthquake fault

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    Porreca, M.; Mochales Lopez, T.; Smedile, A.; Buratti, N.; Macri', P.; Di Chiara, A.; Nicolosi, I.; D'ajello Caracciolo, F.; Carluccio, R.; Di Giulio, G.; Vassallo, M.; Amoroso, S.; Villani, F.; Tallini, M.; Sagnotti, L.; Speranza, F.

    2013-12-01

    INSAR images showed that the 2009 Mw=6.1 normal faulting L'Aquila earthquake produced a maximum co-seismic subsidence of ca. 15 cm in the depocenter of the Middle Aterno basin (Abruzzi, central Italy), on the hanging-wall of the Paganica fault. This continental basin is one of the several fault-controlled extensional basins of the central Apennines and its sedimentation history is poorly known due to the scarcity of outcrops in the weakly incised infilling cover. During May-June 2013, a 151 m deep borehole was drilled in the basin depocenter, as shown by INSAR images. The recovered core (LAqui-core) consists of continental Holocene and Pleistocene clastic sediments and it do not reach the basin substrate. In the same area, we have also performed preliminary geological and geophysical (electrical resistivity tomography and seismic noise survey) investigations in order to select the best drilling location. We have also taken into account recently published high-resolution seismic tomographic data acquired in the same area, showing an evident thickening of low Vp sediments in correspondence of the depocenter. These approaches have been useful to infer the geometry and sedimentary facies architecture of the basin. A first general stratigraphic setting has been defined by means of lithostratigraphic description of the core. It can be subdivided in two main sequences. The upper sequence is composed by 41 meters of silt and sand deposits, interbedded with m-thick rounded gravel intervals. This sequence is interpreted as related to fluvial-alluvial fan depositional environments. An erosional discontinuity separates this upper sequence from the lower clay and sand sequence, typical of a lacustrine depositional environment. The lacustrine sequence continues till the bottom of the borehole and is interrupted in the middle by a 30 m thick coarse gravel deposit. On this stratigraphic record we have collected samples for different kind of analyses (now in progress), involving

  18. Slip distributions on active normal faults measured from LiDAR and field mapping of geomorphic offsets: an example from L'Aquila, Italy, and implications for modelling seismic moment release

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    Wilkinson, Maxwell; Roberts, Gerald P.; McCaffrey, Ken; Cowie, Patience A.; Faure Walker, Joanna P.; Papanikolaou, Ioannis; Phillips, Richard J.; Michetti, Alessandro Maria; Vittori, Eutizio; Gregory, Laura; Wedmore, Luke; Watson, Zoë K.

    2015-05-01

    Surface slip distributions for an active normal fault in central Italy have been measured using terrestrial laser scanning (TLS), in order to assess the impact of changes in fault orientation and kinematics when modelling subsurface slip distributions that control seismic moment release. The southeastern segment of the surface trace of the Campo Felice active normal fault near the city of L'Aquila was mapped and surveyed using techniques from structural geology and using TLS to define the vertical and horizontal offsets of geomorphic slopes since the last glacial maximum (15 ± 3 ka). The fault geometry and kinematics measured from 43 sites and throw/heave measurements from geomorphic offsets seen on 250 scarp profiles were analysed using a modification of the Kostrov equations to calculate the magnitudes and directions of horizontal principal strain-rates. The map trace of the studied fault is linear, except where a prominent bend has formed to link across a former left-stepping relay-zone. The dip of the fault and slip direction are constant across the bend. Throw-rates since 15 ± 3 ka decrease linearly from the fault centre to the tip, except in the location of the prominent bend where higher throw rates are recorded. Vertical coseismic offsets for two palaeo earthquake ruptures seen as fresh strips of rock at the base of the bedrock scarp also increase within the prominent bend. The principal strain-rate, calculated by combining strike, dip, slip-direction and post 15 ± 3 ka throw rate, decreases linearly from the fault centre towards the tip; the strain-rate does not increase across the prominent fault bend. The above shows that changes in fault strike, whilst having no effect on the principal horizontal strain-rate, can produce local maxima in throw-rates during single earthquakes that persist over the timescale of multiple earthquakes (15 ± 3 ka). Detailed geomorphological and structural characterisation of active faults is therefore a critical

  19. Imaging the structural style of an active normal fault through multidisciplinary geophysical investigation: a case study from the Mw 6.1, 2009 L'Aquila earthquake region (central Italy)

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    Villani, Fabio; Pucci, Stefano; Civico, Riccardo; De Martini, Paolo Marco; Nicolosi, Iacopo; D'Ajello Caracciolo, Francesca; Carluccio, Roberto; Di Giulio, Giuseppe; Vassallo, Maurizio; Smedile, Alessandra; Pantosti, Daniela

    2015-03-01

    The normal fault-system responsible of the 2009 Mw 6.1 L'Aquila earthquake (Paganica-San Demetrio fault-system) comprises several narrow, fault-parallel valleys of controversial origin. We investigated a key section of the southeastern portion of this fault network along the small Verupola Valley. In order to characterize its nature and possible tectonic activity, we applied multiple-geosciences techniques able to image at depth the structure associated to this peculiar landform. We integrated magnetometry, 2-D P wave and resistivity tomography, surface waves and seismic noise analysis coupled with field mapping, shallow boreholes and trenching. According to our results, the Verupola Valley is a ˜30-40-m-deep graben controlled by a SW-dipping master fault and synthetic splays paired with an antithetic NE-dipping fault. The SW-dipping splays are active and cut very shallow (<2 m deep) Late Pleistocene sediments. The small amount of cumulated vertical offset (˜15 m) across the conjugated system may indicate a young fault inception or very low Quaternary slip-rates. Due to its structural continuity with the adjacent mapped strands of the Paganica-San Demetrio fault network, we relate the Verupola Valley to the recent activity of the southeastern segment of this fault system. We also suggest that other fault-parallel valleys can have the same tectonic origin and setting of the Verupola Valley. This latter represents a scale-independent analogue from metric scale (exposed in the palaeoseismological trenches) to the Middle Aterno Basin scale (seen from seismic profiles and fault mapping). Overall, the imaged structural style is coherent with the regional tectonic setting due to Quaternary crustal extension.

  20. Geological modeling of a fault zone in clay rocks at the Mont-Terri laboratory (Switzerland)

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    Kakurina, M.; Guglielmi, Y.; Nussbaum, C.; Valley, B.

    2016-12-01

    Clay-rich formations are considered to be a natural barrier for radionuclides or fluids (water, hydrocarbons, CO2) migration. However, little is known about the architecture of faults affecting clay formations because of their quick alteration at the Earth's surface. The Mont Terri Underground Research Laboratory provides exceptional conditions to investigate an un-weathered, perfectly exposed clay fault zone architecture and to conduct fault activation experiments that allow explore the conditions for stability of such clay faults. Here we show first results from a detailed geological model of the Mont Terri Main Fault architecture, using GoCad software, a detailed structural analysis of 6 fully cored and logged 30-to-50m long and 3-to-15m spaced boreholes crossing the fault zone. These high-definition geological data were acquired within the Fault Slip (FS) experiment project that consisted in fluid injections in different intervals within the fault using the SIMFIP probe to explore the conditions for the fault mechanical and seismic stability. The Mont Terri Main Fault "core" consists of a thrust zone about 0.8 to 3m wide that is bounded by two major fault planes. Between these planes, there is an assembly of distinct slickensided surfaces and various facies including scaly clays, fault gouge and fractured zones. Scaly clay including S-C bands and microfolds occurs in larger zones at top and bottom of the Mail Fault. A cm-thin layer of gouge, that is known to accommodate high strain parts, runs along the upper fault zone boundary. The non-scaly part mainly consists of undeformed rock block, bounded by slickensides. Such a complexity as well as the continuity of the two major surfaces are hard to correlate between the different boreholes even with the high density of geological data within the relatively small volume of the experiment. This may show that a poor strain localization occurred during faulting giving some perspectives about the potential for

  1. The shallow structure of the 2009 Mw 6.1 L'Aquila earthquake fault-system (Italy): new insights from integrated high-resolution refraction tomography and detailed geologic mapping

    Science.gov (United States)

    Villani, Fabio; Improta, Luigi; Pucci, Stefano; Civico, Riccardo; Pantosti, Daniela

    2015-04-01

    The 6 April 2009 Mw 6.1 L'Aquila earthquake (central Italy) was caused by the Paganica Fault, which belongs to a ~20 km long network of normal faults (Paganica-San Demetrio Fault System, PSDFS). The hangingwall of the PSDFS hosts a wide Quaternary continental basin (Middle Aterno valley) with complex geometry, structural setting and sedimentary evolution. Before the 2009 earthquake, the shallow crustal structure in the epicentral area was poorly known. Here, we report results of a 2-D high-resolution seismic investigation carried out in 2010 in the NE portion of the basin, across the Paganica Fault, in a challenging urban environment. The survey consisted of 5 dense wide-aperture seismic profiles that run NE-SW for a total length of 8 km. Around 80,000 hand-picked first-arrival traveltimes were input to a non-linear multi-scale tomographic inversion. The merged profiles allow depicting a reliable cross-section of the Middle Aterno basin down to ~300 m depth. In addition, we show for the first time P-wave velocity images across the causative fault of the 6 April 2009 earthquake. Interpretation of the Vp tomograms is constrained by a few drillings and by results of a detailed geologic survey. We interpret low-Vp regions (1500-2000 m/s) as lacustrine sediments and higher Vp bodies (Vp up to 3000 m/s) as coarse fluvial and alluvial fan deposits sited above a Meso-Cenozoic carbonate substratum (Vp >3500-4000 m/s) that shows a very irregular morphology. The improved knowledge of the Middle Aterno valley geological setting together with new tomographic Vp images yield new insights on the buried structure and long-term evolution of two small basins (Bazzano and Paganica basins) crossed by the seismic lines. In particular, the Paganica basin developed since Early-Middle Pleistocene due to the Paganica SW-dipping master fault and its splays. Seismic imaging revealed that the basin infill consists almost exclusively of coarse alluvial fan deposits. We were able to detect 2

  2. Monte Carlo simulation for slip rate sensitivity analysis in Cimandiri fault area

    Energy Technology Data Exchange (ETDEWEB)

    Pratama, Cecep, E-mail: great.pratama@gmail.com [Graduate Program of Earth Science, Faculty of Earth Science and Technology, ITB, JalanGanesa no. 10, Bandung 40132 (Indonesia); Meilano, Irwan [Geodesy Research Division, Faculty of Earth Science and Technology, ITB, JalanGanesa no. 10, Bandung 40132 (Indonesia); Nugraha, Andri Dian [Global Geophysical Group, Faculty of Mining and Petroleum Engineering, ITB, JalanGanesa no. 10, Bandung 40132 (Indonesia)

    2015-04-24

    Slip rate is used to estimate earthquake recurrence relationship which is the most influence for hazard level. We examine slip rate contribution of Peak Ground Acceleration (PGA), in probabilistic seismic hazard maps (10% probability of exceedance in 50 years or 500 years return period). Hazard curve of PGA have been investigated for Sukabumi using a PSHA (Probabilistic Seismic Hazard Analysis). We observe that the most influence in the hazard estimate is crustal fault. Monte Carlo approach has been developed to assess the sensitivity. Then, Monte Carlo simulations properties have been assessed. Uncertainty and coefficient of variation from slip rate for Cimandiri Fault area has been calculated. We observe that seismic hazard estimates is sensitive to fault slip rate with seismic hazard uncertainty result about 0.25 g. For specific site, we found seismic hazard estimate for Sukabumi is between 0.4904 – 0.8465 g with uncertainty between 0.0847 – 0.2389 g and COV between 17.7% – 29.8%.

  3. Monte Carlo simulation for slip rate sensitivity analysis in Cimandiri fault area

    Science.gov (United States)

    Pratama, Cecep; Meilano, Irwan; Nugraha, Andri Dian

    2015-04-01

    Slip rate is used to estimate earthquake recurrence relationship which is the most influence for hazard level. We examine slip rate contribution of Peak Ground Acceleration (PGA), in probabilistic seismic hazard maps (10% probability of exceedance in 50 years or 500 years return period). Hazard curve of PGA have been investigated for Sukabumi using a PSHA (Probabilistic Seismic Hazard Analysis). We observe that the most influence in the hazard estimate is crustal fault. Monte Carlo approach has been developed to assess the sensitivity. Then, Monte Carlo simulations properties have been assessed. Uncertainty and coefficient of variation from slip rate for Cimandiri Fault area has been calculated. We observe that seismic hazard estimates is sensitive to fault slip rate with seismic hazard uncertainty result about 0.25 g. For specific site, we found seismic hazard estimate for Sukabumi is between 0.4904 - 0.8465 g with uncertainty between 0.0847 - 0.2389 g and COV between 17.7% - 29.8%.

  4. Effective crustal permeability controls fault evolution: An integrated structural, mineralogical and isotopic study in granitic gneiss, Monte Rosa, northern Italy

    Science.gov (United States)

    Lawther, Susan E. M.; Dempster, Tim J.; Shipton, Zoe K.; Boyce, Adrian J.

    2016-10-01

    Two dextral faults within granitic gneiss in the Monte Rosa nappe, northern Italy reveal key differences in their evolution controlled by evolving permeability and water/rock reactions. The comparison reveals that identical host rock lithologies develop radically different mineralogies within the fault zones, resulting in fundamentally different deformation histories. Oxygen and hydrogen isotope analyses coupled to microstructural characterisation show that infiltration of meteoric water occurred into both fault zones. The smaller Virgin Fault shows evidence of periodic closed system behaviour, which promoted the growth of hydrothermal K-feldspar, whilst the more open system behaviour of the adjacent Ciao Ciao Fault generated a weaker muscovite-rich fault core, which promoted a step change in fault evolution. Effective crustal permeability is a vital control on fault evolution and, coupled to the temperature (i.e. depth) at which key mineral transformations occur, is probably a more significant factor than host rock strength in controlling fault development. The study suggests that whether a fault in granitic basement grows into a large structure may be largely controlled by the initial hydrological properties of the host rocks. Small faults exposed at the surface may therefore be evolutionary "dead-ends" that typically do not represent the early stages in the development of larger faults.

  5. Formation of chlorite during thrust fault reactivation. Record of fluid origin and P-T conditions in the Monte Perdido thrust fault (southern Pyrenees)

    Science.gov (United States)

    Lacroix, B.; Charpentier, D.; Buatier, M.; Vennemann, T.; Labaume, P.; Adatte, T.; Travé, A.; Dubois, M.

    2012-06-01

    The chemical and isotopic compositions of clay minerals such as illite and chlorite are commonly used to quantify diagenetic and low-grade metamorphic conditions, an approach that is also used in the present study of the Monte Perdido thrust fault from the South Pyrenean fold-and-thrust belt. The Monte Perdido thrust fault is a shallow thrust juxtaposing upper Cretaceous-Paleocene platform carbonates and Lower Eocene marls and turbidites from the Jaca basin. The core zone of the fault, about 6 m thick, consists of intensely deformed clay-bearing rocks bounded by major shear surfaces. Illite and chlorite are the main hydrous minerals in the fault zone. Illite is oriented along cleavage planes while chlorite formed along shear veins (<50 μm in thickness). Authigenic chlorite provides essential information about the origin of fluids and their temperature. δ18O and δD values of newly formed chlorite support equilibration with sedimentary interstitial water, directly derived from the local hanging wall and footwall during deformation. Given the absence of large-scale fluid flow, the mineralization observed in the thrust faults records the P-T conditions of thrust activity. Temperatures of chlorite formation of about 240°C are obtained via two independent methods: chlorite compositional thermometers and oxygen isotope fractionation between cogenetic chlorite and quartz. Burial depth conditions of 7 km are determined for the Monte Perdido thrust reactivation, coupling calculated temperature and fluid inclusion isochores. The present study demonstrates that both isotopic and thermodynamic methods applied to clay minerals formed in thrust fault are useful to help constrain diagenetic and low-grade metamorphic conditions.

  6. Analysis of a 150 m sediment core from the co-seismic subsidence depocenter of the 2009 Mw = 6.1 L'Aquila earthquake (Italy): Implications for Holocene-Pleistocene tectonic subsidence rates and for the age of the seismogenic Paganica fault system

    Science.gov (United States)

    Macrì, P.; Smedile, A.; Speranza, F.; Sagnotti, L.; Porreca, M.; Mochales, T.; Russo Ermolli, E.

    2016-09-01

    LAQUI-CORE was drilled in the co-seismic subsidence depocenter shown by DinSAR images in the Bazzano sub-basin after the 2009 Mw = 6.1 L'Aquila earthquake. LAQUI-CORE aimed at gathering high-resolution integrated stratigraphy and defining its relationships with the Paganica and other active faults that yielded co-seismic subsidence. Lithostratigraphy and micropaleontological analyses indicate a Late Pleistocene-Holocene fluvial-alluvial sequence, and below 41 m palustrine sediments sandwiching at 84-115 m a thick gravel package. Four 14C ages gathered from 5 to 15 m yield calibrated ages between 6 and 41 ka BP. Paleomagnetism reveals a normal polarity above 84 m, while below the gravel package (115 m) it shows frequent polarity changes. The occurrence of intervals of clear reverse polarity testifies below 115 m the deposition during the Matuyama Chron. We conclude that the normal polarity package, down to 84 m along with the underlying gravels, were deposited at high sedimentation rate (0.46 mm/yr for the upper 15 m) during the Brunhes Chron (normal polarity sequence was due to the activity of the Paganica and neighbour faults during the Middle-Late Pleistocene. The lack of thick volcanostratigraphic markers, widespread in colluvial sediments from the L'Aquila plain older than 460 ka, suggests a normal-polarity sedimentation onset, thus a Paganica fault activity onset, around 400 ka. The 0.25 to 0.50 mm/yr subsidence at Bazzano extrapolated by DinSAR data and paleoseismological trenching at the Paganica fault is roughly consistent with the sedimentation rate (0.46 mm/yr) yielded by radiocarbon dating in the upper LAQUI-CORE. This implies that co-seismic subsidence in the Bazzano sub-basin during Late Pleistocene-Holocene times was mainly controlled by the Paganica fault activity.

  7. Reliability analysis of a wastewater treatment plant using fault tree analysis and Monte Carlo simulation.

    Science.gov (United States)

    Taheriyoun, Masoud; Moradinejad, Saber

    2015-01-01

    The reliability of a wastewater treatment plant is a critical issue when the effluent is reused or discharged to water resources. Main factors affecting the performance of the wastewater treatment plant are the variation of the influent, inherent variability in the treatment processes, deficiencies in design, mechanical equipment, and operational failures. Thus, meeting the established reuse/discharge criteria requires assessment of plant reliability. Among many techniques developed in system reliability analysis, fault tree analysis (FTA) is one of the popular and efficient methods. FTA is a top down, deductive failure analysis in which an undesired state of a system is analyzed. In this study, the problem of reliability was studied on Tehran West Town wastewater treatment plant. This plant is a conventional activated sludge process, and the effluent is reused in landscape irrigation. The fault tree diagram was established with the violation of allowable effluent BOD as the top event in the diagram, and the deficiencies of the system were identified based on the developed model. Some basic events are operator's mistake, physical damage, and design problems. The analytical method is minimal cut sets (based on numerical probability) and Monte Carlo simulation. Basic event probabilities were calculated according to available data and experts' opinions. The results showed that human factors, especially human error had a great effect on top event occurrence. The mechanical, climate, and sewer system factors were in subsequent tier. Literature shows applying FTA has been seldom used in the past wastewater treatment plant (WWTP) risk analysis studies. Thus, the developed FTA model in this study considerably improves the insight into causal failure analysis of a WWTP. It provides an efficient tool for WWTP operators and decision makers to achieve the standard limits in wastewater reuse and discharge to the environment.

  8. Verification of Transformer Restricted Earth Fault Protection by using the Monte Carlo Method

    Directory of Open Access Journals (Sweden)

    KRSTIVOJEVIC, J. P.

    2015-08-01

    Full Text Available The results of a comprehensive investigation of the influence of current transformer (CT saturation on restricted earth fault (REF protection during power transformer magnetization inrush are presented. Since the inrush current during switch-on of unloaded power transformer is stochastic, its values are obtained by: (i laboratory measurements and (ii calculations based on the input data obtained by the Monte Carlo (MC simulation. To make a detailed assessment of the current transformer performance the uncertain input data for the CT model were obtained by applying the MC method. In this way, different levels of remanent flux in CT core are taken into consideration. By the generated CT secondary currents, the algorithm for REF protection based on phase comparison in time domain is tested. On the basis of the obtained results, a method of adjustment of the triggering threshold in order to ensure safe operation during transients, and thereby improve the algorithm security, has been proposed. The obtained results indicate that power transformer REF protection would be enhanced by using the proposed adjustment of triggering threshold in the algorithm which is based on phase comparison in time domain.

  9. L'Aquila verdict quashed

    Science.gov (United States)

    Banks, Michael

    2014-12-01

    Six of the seven scientists and engineers who were controversially found guilty of manslaughter for the role that they played in the 2009 L’Aquila earthquake have been cleared after a month-long appeal trial.

  10. The Fault Geometry and Surface Ruptures, the Damage Pattern and the Deformation Field of the 6th and 7th of April 2009, Mw=6.3 and Mw=5.6 Earthquakes in L'Aquila (Central Italy) Revealed by Ground and Space Based Observations

    Science.gov (United States)

    Papanikolaou, Ioannis; Roberts, Gerald; Foumelis, Michael; Parcharidis, Issaac; Lekkas, Efthimios; Fountoulis, Ioannis

    2010-05-01

    The 2009 Mw=6.3 L' Aquila earthquake in central Italy despite its moderate magnitude caused significant loss of life and damages, producing the highest death toll in the E.U. since the 1980 Mw=6.9 Irpinia event and the highest economic cost since the 1999 Ms=5.9 Athens earthquake. It is now recognized that such events pose a high risk in most extensional settings, such as Europe at large due both to its high rate of occurrence and proximity to human habitation, forming a typical case study scenario. The deformation pattern of the 6th and 7th of April 2009 Mw=6.3 and Mw=5.6 earthquakes in L' Aquila is revealed by DInSAR analysis and compared with earthquake environmental effects. The DInSAR predicted fault surface ruptures coincide with localities where surface ruptures have been observed in the field, confirming that the ruptures observed near Paganica village are indeed primary. These ruptures are almost one order of magnitude lower than the ruptures that have been produced by other major surrounding faults from historical earthquakes. This event ruptured a small fault segment of the fault system and not one of the major postglacial fault scarps that outcrop in the area. This explains the minor primary surface ruptures that have been reported so that the 2009 L' Aquila event can be characterized as belonging to the lower end member concerning the capacity of the existing seismic sources of the area.These faults have not been activated during the 2009 event, but have the capacity to generate significantly stronger events. DInSAR analysis shows that 66% (or 305 km2) of the area deformed has been subsided whereas the remaining 34% (or 155 km2) has been uplifted. A footwall uplift versus hangingwall subsidence ratio of about 1/3 is extracted from the mainshock. The maximum subsidence (25cm) was recorded about 4.5 km away from the primary surface ruptures and about 9km away from the epicentre. In the immediate hangingwall, subsidence did not exceeded 15cm, showing that

  11. Faults

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Through the study of faults and their effects, much can be learned about the size and recurrence intervals of earthquakes. Faults also teach us about crustal...

  12. The complex architecture of the 2009 MW 6.1 L'Aquila normal fault system (Central Italy) as imaged by 64,000 high-resolution aftershock locations

    Science.gov (United States)

    Valoroso, L.; Chiaraluce, L.; Di Stefano, R.; Piccinini, D.; Schaff, D. P.; Waldhauser, F.

    2011-12-01

    On April 6th 2009, a MW 6.1 normal faulting earthquake struck the axial area of the Abruzzo region in Central Italy. We present high-precision hypocenter locations of an extraordinary dataset composed by 64,000 earthquakes recorded at a very dense seismic network of 60 stations operating for 9 months after the main event. Events span in magnitude (ML) between -0.9 to 5.9, reaching a completeness magnitude of 0.7. The dataset has been processed by integrating an accurate automatic picking procedure together with cross-correlation and double-difference relative location methods. The combined use of these procedures results in earthquake relative location uncertainties in the range of a few meters to tens of meters, comparable/lower than the spatial dimension of the earthquakes themselves). This data set allows us to image the complex inner geometry of individual faults from the kilometre to meter scale. The aftershock distribution illuminates the anatomy of the en-echelon fault system composed of two major faults. The mainshock breaks the entire upper crust from 10 km depth to the surface along a 14-km long normal fault. A second segment, located north of the normal fault and activated by two Mw>5 events, shows a striking listric geometry completely blind. We focus on the analysis of about 300 clusters of co-located events to characterize the mechanical behavior of the different portions of the fault system. The number of events in each cluster ranges from 4 to 24 events and they exhibit strongly correlated seismograms at common stations. They mostly occur where secondary structures join the main fault planes and along unfavorably oriented segments. Moreover, larger clusters nucleate on secondary faults located in the overlapping area between the two main segments, where the rate of earthquake production is very high with a long-lasting seismic decay.

  13. Quick moment tensor solution for 6 April 2009, L'Aquila, Italy, earthquake

    Institute of Scientific and Technical Information of China (English)

    Chao Liu; Lisheng Xu; Yuntai Chen

    2009-01-01

    A MW6.4 earthquake occurred in L'Aquila, central Italy at 1:32:42 (UTC), April 6, 2009. We quickly obtained the moment tensor solution of the earthquake by inverting the P waveforms of broadband recordings from the global seismo-graphic network (GSN) stations using the quick technique of moment tensor inversion, and further inferred that the nodal plane of strike 132°, dip 53° and rake -103° is the seismogenic fault.

  14. Along-strike rupture directivity of earthquakes of the 2009 L'Aquila, central Italy, seismic sequence

    Science.gov (United States)

    Calderoni, G.; Rovelli, A.; Ben-Zion, Y.; Di Giovambattista, R.

    2015-10-01

    We perform a systematic investigation of along-strike rupture directivity of 70 earthquakes (3.0 ≤ Mw ≤ 6.1) of the 2009 L'Aquila seismic sequence by analysing azimuthal variations of broad-band seismograms recorded in the distance range 60 km earthquake quantifies the spectral separation above the corner frequency of the target event at opposite along-strike directions. A large number (73 per cent) of events including the Mw 6.1 main shock show high (>0.7) IDIR values indicating predominantly unilateral rupture propagation. The preferred rupture propagation direction is generally to the southeast with no dependence on the earthquake magnitude or occurrence time. Events on two main faults (L'Aquila and Campotosto) show somewhat different behaviour. Almost all earthquakes on the L'Aquila fault have strong unilateral directivity to the southeast, whereas earthquakes on the Campotosto fault show more diverse behaviour. However, there is a predominance of unilateral ruptures (14 out of 22) also on the Campotosto fault, and the few (five) earthquakes with ruptures to the northwest are limited to the most northwestern segment of the fault. The spectral results are consistent with time-domain analysis when the latter samples adequately the frequency band above corner frequency. The preferred rupture direction may be produced at least in part by a velocity contrast across the fault. The results provide important input for estimates of seismic motion and physics of earthquake ruptures.

  15. Up-dip directivity in near-source during the 2009 L'Aquila main shock

    Science.gov (United States)

    Tinti, Elisa; Scognamiglio, Laura; Cirella, Antonella; Cocco, Massimo

    2014-09-01

    In this study we have investigated the directivity associated with the initial up-dip rupture propagation during the 2009 April 6 (Mw 6.1) L'Aquila normal-faulting earthquake. The objective is the understanding of how the peculiar initial behaviour of rupture history during the main shock has affected the near-source recorded ground motions in the L'Aquila town and surrounding areas. We have modelled the observed ground velocities at the closest near-source recording sites by computing synthetic seismograms using a discrete wavenumbers and finite difference approach in the low frequency bandwidth (0.02-0.4 Hz) to avoid site effects contaminations. We use both the rupture model retrieved by inverting ground motion waveforms and continuous high sampling-rate GPS time-series as well as uniform-slip constant-rupture speed models. Our results demonstrate that the initial up-dip rupture propagation, characterizing the first 3 s of the rupture history during the L'Aquila main shock and releasing only ˜25 per cent of total seismic moment, controls the observed ground motions in the near-source. This initial stage of the rupture is characterized by the generation of ground velocity pulses, which we interpret as a forward directivity effect. Our modelling results confirm a heterogeneous distribution of rupture velocity during the initial up-dip rupture propagation, since uniform rupture speed models overestimate up-dip directivity effects in the footwall of the causative fault. The up-dip directivity observed in the near field during the 2009 L'Aquila main shock is that expected for a normal faulting earthquake, but it differs from that inferred from far-field observations that conversely provide evidence of along-strike directivity. This calls for a careful analysis as well as for the realistic inclusion of rupture directivity to predict ground motions in the near source.

  16. Fault Diagnosis Method under the Condition of Redundant Constraint Based on Monte Carlo Simulation%基于Monte Carlo仿真的夹具过定位故障诊断方法

    Institute of Scientific and Technical Information of China (English)

    张利; 周志革; 黄文振

    2001-01-01

    现实生产中,由于夹具定位元件的磨损、松动、弯曲和断裂,使得夹具不能够对零件进行精确定位.针对目前实际生产中夹具过定位普遍存在且缺少相应的故障诊断方法的情况,提出了应用统计方法进行夹具的故障诊断.夹具过定位故障诊断模型只需用工件的几何信息,同时模型可给出相应的故障报警概率.Monte Carl0模拟结果表明了该方法的正确性.%The parts can not be located accurately because of the worn, loose or broken location elements in the process of assembly of body in white, and this is the main cause for assembly tolerance of body in white. Fault diagnosis method only follows the 3-2-1 fixturing principle now. There is not a clear geometric relationship between the location element displacement and measurement point variation under the condition of redundant constraint. In this paper, Monte Carlo method was used to simulate positions of a part, and a model was presented to diagnose the fault based on statistical data, which gives the probability of detecting faults and the probability of false alarms also. The results of the Monte Carlo simulation show that this method is reasonable.

  17. The August 24th 2016 Accumoli earthquake: surface faulting and Deep-Seated Gravitational Slope Deformation (DSGSD in the Monte Vettore area

    Directory of Open Access Journals (Sweden)

    Domenico Aringoli

    2016-11-01

    Full Text Available On August 24th 2016 a Mw=6.0 earthquake hit central Italy, with the epicenter located at the boundaries between Lazio, Marche, Abruzzi and Umbria regions, near the village of Accumoli (Rieti, Lazio. Immediately after the mainshock, this geological survey has been focused on the earthquake environmental effects related to the tectonic reactivation of the previously mapped active fault (i.e. primary, as well as secondary effects mostly related to the seismic shaking (e.g. landslides and fracturing in soil and rock.This paper brings data on superficial effects and some preliminary considerations about the interaction and possible relationship between surface faulting and the occurrence of Deep-Seated Gravitational Slope Deformation (DSGSD along the southern and western slope of Monte Vettore.

  18. Experimental evidence of electrification processes during the 2009 L'Aquila earthquake main shock

    Science.gov (United States)

    Nenovski, P.

    2015-09-01

    Two types of coseismic magnetic field events are simultaneously observed: transient offset events and magnetic field signal that occurred at the destructive, Mw6.1 L'Aquila earthquake main shock. The offset event, conventionally interpreted as a signature of piezomagnetic effects, however, could not be explained as such. In the second type of coseismic event, the transient magnetic signal starts simultaneously with the offset event and reaches amplitude of 0.8 nT in the total magnetic field. The signal is a local one; its amplitude shape resembles diffusion-like form with time scale characteristics that are indicative for a source deep in the crust. The polarity of the transient signal is in the horizontal plane and nearly parallel to the L'Aquila fault strike.

  19. The Bright Symbiotic Mira EF Aquilae

    CERN Document Server

    Margon, Bruce; Tejos, Nicolas; Monroe, TalaWanda

    2016-01-01

    An incidental spectrum of the poorly studied long period variable EF Aquilae shows [O III] emission indicative of a symbiotic star. Strong GALEX detections in the UV reinforce this classification, providing overt evidence for the presence of the hot subluminous companion. Recent compilations of the photometric behavior strongly suggest that the cool component is a Mira variable. Thus EF Aql appears to be a member of the rare symbiotic Mira subgroup.

  20. Marked increase in substance use among young people after L?Aquila earthquake

    OpenAIRE

    Pollice, Rocco; Bianchini, Valeria; Roncone, Rita; Casacchia, Massimo

    2011-01-01

    Marked increase in substance use among young people after L?Aquila earthquake (Pollice, Rocco) Department of Health Sciences, Psychiatric Unit, `San Salvatore? Hospital, University of L?Aquila - L?Aquila - ITALY (Pollice, Rocco) Department of Health Sciences, Psychiatric Unit, University of L?Aquila - Via Vetoio, Loc. Coppito - 67100 - L?Aquila - ITALY (Pollice, Rocco) Department of Health Sciences, Psychiatric Unit, `San Salvatore? Hospital, Universi...

  1. Non-inductive components of electromagnetic signals associated with L'Aquila earthquake sequences estimated by means of inter-station impulse response functions

    Directory of Open Access Journals (Sweden)

    C. Di Lorenzo

    2011-04-01

    Full Text Available On 6 April 2009 at 01:32:39 UT a strong earthquake occurred west of L'Aquila at the very shallow depth of 9 km. The main shock local magnitude was Ml = 5.8 (Mw = 6.3. Several powerful aftershocks occurred the following days. The epicentre of the main shock occurred 6 km away from the Geomagnetic Observatory of L'Aquila, on a fault 15 km long having a NW-SE strike, about 140°, and a SW dip of about 42°. For this reason, L'Aquila seismic events offered very favourable conditions to detect possible electromagnetic emissions related to the earthquake. The data used in this work come from the permanent geomagnetic Observatories of L'Aquila and Duronia. Here the results concerning the analysis of the residual magnetic field estimated by means of the inter-station impulse response functions in the frequency band from 0.3 Hz to 3 Hz are shown.

  2. Macroseismic survey of the April 6, 2009 L’Aquila earthquake (central Italy)

    Science.gov (United States)

    Camassi, R.; Azzaro, R.; Bernardini, F.; D'Amico, S.; Ercolani, E.; Rossi, A.; Tertulliani, A.; Vecchi, M.; Galli, P.

    2009-12-01

    On April 6, 2009, at 01:33 GMT, central Italy has been hit by a strong earthquake (Ml 5.8, Mw 6.3) representing the mainshock of a seismic sequence of over 20.000 aftershocks recorded in about five months. The event, located in the inner of the Abruzzi region just a few kilometres SW of the town of L’Aquila, has produced destructions and heavy damage in a 30 km wide area and was felt in almost Italy, as far as the coasts of Slovenia, Croatia and Albania. In all, 308 people lost their lives. A macroseismic survey was carried out soon after the earthquake by the QUEST group (QUick Earthquake Survey Team) with the aim to define, for Civil Protection purposes, the damage scenario over a territory which is densely urbanised. Damage generally depended on the high vulnerability of the buildings both for problems related to the old age of the buildings - it is the case of the historical centre of l’Aquila - and to site effects, as in some quarters of the town and in the nearby villages. Rubble-stone and masonry buildings suffered heaviest damage - a lot of old small villages almost entirely collapsed - while reinforced concrete (RC) frame buildings generally experienced moderate structural damage except in particular condition. The macroseismic effects reached intensity IX-X MCS (Mercalli-Cancani-Sieberg scale) at Onna and Castelnuovo, while many others villages reached VIII-IX MCS, amongst which the historical centre of L’Aquila. This town was investigated in detail due to the striking difference of damage between the historical centre and the more recent surrounding areas. In all, more than 300 localities have been investigated (Galli and Camassi, 2009). The earthquake has also provoked effects on natural surroundings (EMERGEO WG, 2009). Two types of phenomena have been detected: (i) surface cracks mainly observed along previously mapped faults and (ii) slope instability processes, such as landslides and secondary fractures. The pattern of macroseismic effects

  3. Rapid response seismic networks in Europe: lessons learnt from the L'Aquila earthquake emergency

    Directory of Open Access Journals (Sweden)

    Angelo Strollo

    2011-08-01

    Full Text Available

    The largest dataset ever recorded during a normal fault seismic sequence was acquired during the 2009 seismic emergency triggered by the damaging earthquake in L'Aquila (Italy. This was possible through the coordination of different rapid-response seismic networks in Italy, France and Germany. A seismic network of more than 60 stations recorded up to 70,000 earthquakes. Here, we describe the different open-data archives where it is possible to find this unique set of data for studies related to hazard, seismotectonics and earthquake physics. Moreover, we briefly describe some immediate and direct applications of emergency seismic networks. At the same time, we note the absence of communication platforms between the different European networks. Rapid-response networks need to agree on common strategies for network operations. Hopefully, over the next few years, the European Rapid-Response Seismic Network will became a reality.

  4. How to predict Italy L'Aquila M6.3 earthquake

    Science.gov (United States)

    Guo, Guangmeng

    2016-04-01

    According to the satellite cloud anomaly appeared over eastern Italy on 21-23 April 2012, we predicted the M6.0 quake occurred in north Italy successfully. Here checked the satellite images in 2011-2013 in Italy, and 21 cloud anomalies were found. Their possible correlation with earthquakes bigger than M4.7 which located in Italy main fault systems was statistically examined by assuming various lead times. The result shows that when the leading time interval is set to 23≤ΔT≤45 days, 8 of the 10 quakes were preceded by cloud anomalies. Poisson random test shows that AAR (anomaly appearance rate) and EOR (EQ occurrence rate) is much higher than the values by chance. This study proved the relation between cloud anomaly and earthquake in Italy. With this method, we found that L'Aquila earthquake can also be predicted according to cloud anomaly.

  5. Uranium groundwater anomalies and L'Aquila earthquake, 6th April 2009 (Italy).

    Science.gov (United States)

    Plastino, Wolfango; Povinec, Pavel P; De Luca, Gaetano; Doglioni, Carlo; Nisi, Stefano; Ioannucci, Luca; Balata, Marco; Laubenstein, Matthias; Bella, Francesco; Coccia, Eugenio

    2010-01-01

    Monitoring of chemical and physical groundwater parameters has been carried out worldwide in seismogenic areas with the aim to test possible correlations between their spatial and temporal variations and strain processes. Uranium (U) groundwater anomalies were observed during the preparation phases of the recent L'Aquila earthquake of 6th April 2009 in the cataclastic rocks near the overthrust fault crossing the deep underground Gran Sasso National Laboratory. The results suggest that U may be used as a potential strain indicator of geodynamic processes occurring before the seismic swarm and the main earthquake shock. Moreover, this justifies the different radon patterns before and after the main shock: the radon releases during and after the earthquake are much than more during the preparatory period because the process does not include only the microfracturing induced by stress-strain activation, but also radon increases accompanying groundwater U anomalies.

  6. Nova Aquila 1919: a nova after all?

    CERN Document Server

    Lau, Herbert H B; Liu, X W

    2010-01-01

    Nova 1919 Aquila is today widely assumed to have been the result of a final helium shell flash occurring on a single post-asymptotic giant branch star. The fact that the outbursting star is in the middle of an old planetary nebula and that the ejecta associated with the outburst is hydrogen deficient supports this diagnosis. However, the material ejected during that outburst is also extremely neon rich, suggesting that it derives from an oxygen-neon-magnesium star, as is the case in the so-called neon novae. We have therefore attempted to construct a scenario that explains all the observations of the nebula and its central star, including the ejecta abundances. We find two scenarios that have the potential to explain the observations, although neither is a perfect match. The first scenario invokes the merger of a main sequence star and a massive oxygen-neon-magnesium white dwarf. The second invokes an oxygen-neon-magnesium classical nova that takes place shortly after a final helium shell flash. The main draw...

  7. Deep electrical resistivity tomography along the tectonically active Middle Aterno Valley (2009 L'Aquila earthquake area, central Italy)

    Science.gov (United States)

    Pucci, Stefano; Civico, Riccardo; Villani, Fabio; Ricci, Tullio; Delcher, Eric; Finizola, Anthony; Sapia, Vincenzo; De Martini, Paolo Marco; Pantosti, Daniela; Barde-Cabusson, Stéphanie; Brothelande, Elodie; Gusset, Rachel; Mezon, Cécile; Orefice, Simone; Peltier, Aline; Poret, Matthieu; Torres, Liliana; Suski, Barbara

    2016-11-01

    Three 2-D Deep Electrical Resistivity Tomography (ERT) transects, up to 6.36 km long, were obtained across the Paganica-San Demetrio Basin, bounded by the 2009 L'Aquila Mw 6.1 normal-faulting earthquake causative fault (central Italy). The investigations allowed defining for the first time the shallow subsurface basin structure. The resistivity images, and their geological interpretation, show a dissected Mesozoic-Tertiary substratum buried under continental infill of mainly Quaternary age due to the long-term activity of the Paganica-San Demetrio normal faults system (PSDFS), ruling the most recent deformational phase. Our results indicate that the basin bottom deepens up to 600 m moving to the south, with the continental infill largely exceeding the known thickness of the Quaternary sequence. The causes of this increasing thickness can be: (1) the onset of the continental deposition in the southern sector took place before the Quaternary, (2) there was an early stage of the basin development driven by different fault systems that produced a depocentre in the southern sector not related to the present-day basin shape, or (3) the fault system slip rate in the southern sector was faster than in the northern sector. We were able to gain sights into the long-term PSDFS behaviour and evolution, by comparing throw rates at different timescales and discriminating the splays that lead deformation. Some fault splays exhibit large cumulative throws (>300 m) in coincidence with large displacement of the continental deposits sequence (>100 m), thus testifying a general persistence in time of their activity as leading splays of the fault system. We evaluate the long-term (3-2.5 Myr) cumulative and Quaternary throw rates of most of the leading splays to be 0.08-0.17 mm yr-1, indicating a substantial stability of the faults activity. Among them, an individual leading fault splay extends from Paganica to San Demetrio ne' Vestini as a result of a post-Early Pleistocene linkage of

  8. Precursory slow-slip loaded the 2009 L'Aquila earthquake sequence

    Science.gov (United States)

    Borghi, A.; Aoudia, A.; Javed, F.; Barzaghi, R.

    2016-05-01

    Slow-slip events (SSEs) are common at subduction zone faults where large mega earthquakes occur. We report here that one of the best-recorded moderate size continental earthquake, the 2009 April 6 moment magnitude (Mw) 6.3 L'Aquila (Italy) earthquake, was preceded by a 5.9 Mw SSE that originated from the decollement beneath the reactivated normal faulting system. The SSE is identified from a rigorous analysis of continuous GPS stations and occurred on the 12 February and lasted for almost two weeks. It coincided with a burst in the foreshock activity with small repeating earthquakes migrating towards the main-shock hypocentre as well as with a change in the elastic properties of rocks in the fault region. The SSE has caused substantial stress loading at seismogenic depths where the magnitude 4.0 foreshock and Mw 6.3 main shock nucleated. This stress loading is also spatially correlated with the lateral extent of the aftershock sequence.

  9. Seismic slip history of the Pizzalto fault (Central Apennines, Italy) using in situ 36Cl cosmogenic dating

    Science.gov (United States)

    Delli Rocioli, Mattia; Pace, Bruno; Benedetti, Lucilla; Visini, Francesco; Guillou, Valery; Bourlès, Didier; Arnorld, Maurice; Aumaître, Georges; Keddadouche, Karim

    2013-04-01

    A prerequisite to constrain fault-based and time-dependent earthquake rupture forecast models is to acquire data on the past large earthquake frequency on an individual seismogenic source. Here we present a paleoseismological study on the Pizzalto fault using the in situ produced cosmogenic nuclide 36Cl (Schlagenhauf et al., 2011). The Pizzalto fault, located in central Italy about 50 km southeast of the epicenter of L'Aquila 2009 earthquake, is about 12 km long, SW dipping and belongs to the 30 km long Rotella-Aremogna active normal fault system. Recent activity along the Pizzalto fault is suggested by the presence of a continuous and linear 2 to 5 m high limestone fault scarp that was sampled every 10 cm at a site located in its particularly well-preserved central portion. 49 samples have been chemically processed and measured, and their 36Cl and Cl concentrations have been determined using isotope dilution mass spectrometry at the French AMS national facility ASTER located at CEREGE. Modeling the in situ 36Cl concentration with the scarp height allow deciphering the age and slip of the last major earthquake events on the fault. To derive those earthquake parameters, we used the published Matlab code from Schlagenhauf et al. (2011) that we implemented with a Monte Carlo approach to explore a large number of earthquake recurrence scenarios varying both the number of events, their slip and their ages. The "a priori" constraints input in the Monte Carlo code were: 1-the number of events, which is given by the stacking of individual probability density functions (assumed to be Gaussian) of each sample concentration; and, 2-the cumulative slip that should be equal to the height of the fault scarp. The first results show that 36Cl concentrations are reproduced better considering five events occurring over the last 5 ka and a previous one at about 13 ka. This suggests that most earthquake events clustered during a period of intense seismic activity preceded by a longer

  10. L'Aquila earthquake verdict yields aftershocks

    Science.gov (United States)

    Showstack, Randy

    2012-11-01

    The 22 October verdict by a court in L'Aquila, Italy, convicting seven Italian earthquake experts of manslaughter for failing to provide an adequate seismic warning to residents prior to a damaging quake in the region continues to send shockwaves through the scientific community. A sampling of the scientific community's concern about the verdict, which is likely to be appealed, included a 25 October joint statement from U.S. National Academy of Sciences president Ralph Cicerone and U.K. Royal Society president Sir Paul Nurse that noted "the difficult task facing scientists in dealing with risk communication and uncertainty." The statement continued, "Much as society and governments would like science to provide simple, clear-cut answers to the problems that we face, it is not always possible. Scientists can, however, gather all the available evidence and offer an analysis of the evidence in light of what they do know. The sensible course is to turn to expert scientists who can provide evidence and advice to the best of their knowledge. They will sometimes be wrong, but we must not allow the desire for perfection to be the enemy of good. That is why we must protest the verdict in Italy. If it becomes a precedent in law, it could lead to a situation in which scientists will be afraid to give expert opinion for fear of prosecution or reprisal. Much government policy and many societal choices rely on good scientific advice and so we must cultivate an environment that allows scientists to contribute what they reasonably can, without being held responsible for forecasts or judgments that they cannot make with confidence."

  11. Testimonies to the L'Aquila earthquake (2009) and to the L'Aquila process

    Science.gov (United States)

    Kalenda, Pavel; Nemec, Vaclav

    2014-05-01

    Lot of confusions, misinformation, false solidarity, efforts to misuse geoethics and other unethical activities in favour of the top Italian seismologists responsible for a bad and superficial evaluation of the situation 6 days prior to the earthquake - that is a general characteristics for the whole period of 5 years separating us from the horrible morning of April 6, 2009 in L'Aquila with 309 human victims. The first author of this presentation as a seismologist had unusual opportunity to visit the unfortunate city in April 2009. He got all "first-hand" information that a real scientifically based prediction did exist already for some shocks in the area on March 29 and 30, 2009. The author of the prediction Gianpaolo Giuliani was obliged to stop any public information diffused by means of internet. A new prediction was known to him on March 31 - in the day when the "Commission of Great Risks" offered a public assurance that any immediate earthquake can be practically excluded. In reality the members of the commission completely ignored such a prediction declaring it as a false alarm of "somebody" (even without using the name of Giuliani). The observations by Giuliani were of high quality from the scientific point of view. G. Giuliani predicted L'Aquila earthquake in the professional way - for the first time during many years of observations. The anomalies, which preceded L'Aquila earthquake were detected on many places in Europe in the same time. The question is, what locality would be signed as potential focal area, if G. Giuliani would know the other observations in Europe. The deformation (and other) anomalies are observable before almost all of global M8 earthquakes. Earthquakes are preceded by deformation and are predictable. The testimony of the second author is based on many unfortunate personal experiences with representatives of the INGV Rome and their supporters from India and even Australia. In July 2010, prosecutor Fabio Picuti charged the Commission

  12. Measuring a truncated disk in Aquila X-1

    DEFF Research Database (Denmark)

    King, Ashley L.; Tomsick, John A.; Miller, Jon M.

    2016-01-01

    We present NuSTAR and Swift observations of the neutron star Aquila X-1 during the peak of its 2014 July outburst. The spectrum is soft with strong evidence for a broad Fe Kα line. Modeled with a relativistically broadened reflection model, we find that the inner disk is truncated with an inner r...

  13. Six of the L'Aquila Seven Acquitted in Appeal

    Science.gov (United States)

    Rosen, Julia

    2014-11-01

    On 10 November, a panel of judges acquitted the scientists charged with manslaughter in the wake of a deadly earthquake that struck the Italian city of L'Aquila in 2009. Only the former deputy director of Italy's Civil Protection Department, Bernardo De Bernardinis, faces a 2-year sentence, which he may not serve.

  14. Coseismic ground deformation of the 6 April 2009 L'Aquila earthquake (central Italy, Mw6.3)

    Science.gov (United States)

    Boncio, P.; Pizzi, A.; Brozzetti, F.; Pomposo, G.; Lavecchia, G.; Di Naccio, D.; Ferrarini, F.

    2010-03-01

    We provide field data of coseismic ground deformation related to the 6 April Mw 6.3 L'Aquila normal faulting earthquake. Three narrow fracture zones were mapped: Paganica-Colle Enzano (P-E), Mt. Castellano-Mt. Stabiata (C-S) and San Gregorio (SG). These zones define 13 km of surface ruptures that strike at 130-140°. We mapped four main types of ground deformation (free faces on bedrock fault scarps, faulting along synthetic splays and fissures with or without slip) that are probably due to the near-surface lithology of the fault walls and the amount of slip that approached the surface coseismically. The P-E and C-S zones are characterized by downthrow to the SW (up to 10 cm) and opening (up to 12 cm), while the SG zone is characterized only by opening. Afterslip throw rates of 0.5-0.6 mm/day were measured along the Paganica fault, where paleoseismic evidence reveals recurring paleo-earthquakes and post-24.8 kyr slip-rate ≥ 0.24 mm/yr.

  15. Surface temperature and precipitation affecting GPS signals before the 2009 L'Aquila earthquake (Central Italy)

    Science.gov (United States)

    Amoruso, A.; Crescentini, L.; Chiaraluce, L.

    2017-08-01

    An Mw 6.1 normal faulting earthquake struck Central Italy in 2009 April, which unfortunately nucleated right below the town of L'Aquila, causing more than 300 casualties and widespread damage. The main shock was preceded by a foreshock sequence lasting ∼6 months. It has been claimed that an analysis of continuous Global Positioning System (GPS) data shows that during the foreshock sequence a 5.9 Mw slow slip event (SSE) occurred along a decollement located beneath the reactivated normal fault system. This hypothesized SSE that started in the middle of 2009 February and lasted for almost two weeks would have eventually loaded the largest foreshock and the main shock. We show that the strain signal that the SSE would have generated at two laser strainmeters operating at about 20 km NE from the SSE source was essentially undetected. We then propose an alternative interpretation for the displacement observed in the GPS data. A transient signal is present in temperature and precipitation time-series recorded close to the GPS station that has largest signal referred to the SSE, implying that these contaminated the GPS record. This work illustrates how environmental noise may be relevant when investigating small strain signals, showing the importance of having data from weather stations and water level sensors colocated with GPS stations.

  16. Reliability Analysis for Electric Multiple Units Based on Fault Tree Monte Carlo Method%基于故障树—蒙特卡洛方法的动车组可靠性分析

    Institute of Scientific and Technical Information of China (English)

    胡川; 姚建伟

    2012-01-01

    建立CRH2型动车组系统及其走行子系统、牵引传动子系统、制动子系统、高压电器子系统、辅助供电子系统以及网络控制子系统的故障树,在此基础上运用蒙特卡洛方法和MATLAB软件,对动车组的可靠性进行仿真分析.结果表明:基于故障树分析的蒙特卡洛仿真方法能快速、准确地计算动车组整车的可靠性;当动车组各基本部件发生故障的概率服从指数分布时,整个动车组系统发生故障的概率也服从指数分布;动车组最重要的3个分系统依次为空气供给分系统、接地保护开关和高压设备箱分系统以及牵引传动分系统.%The fault trees of the CRH2 EMU system as well as its subsystems of running, traction drive, braking, high voltage apparatus, auxiliary power supply and network control were established. On that basis, Monte Carlo method and MATLAB software were applied to simulate and analyze the reliability of the EMU. The results indicate that, Monte Carlo simulation method which is based on fault tree analysis, can rapidly and accurately calculate the reliability of the whole EMU. If the fault probabilities of EMU various basic components obey exponential distribution, then does the fault probability of the whole EMU system. The three most important partial systems of the EMU are, in order, the air supply partial system, the grounding protection switch and high voltage equipment box partial system and traction drive partial system.

  17. Uncertainty analysis of the 2009 L'Aquila rupture model using one- and three-dimensional crustal structure

    Science.gov (United States)

    Razafindrakoto, H. N. T.; Imperatori, W.; Mai, P. M.

    2014-12-01

    Finite-fault rupture models for the 2009 L'Aquila earthquake reveal considerable variability among the published solutions of kinematic source parameters. One potential source of this variability arises from the non-unique choice of crustal structure. This earthquake occurred in an area of complex geology, including a small sedimentary basin and pronounced topography. Therefore, the use of a one-dimensional crustal structure may be insufficient to accurately infer the earthquake rupture process. In this study, we examine the effects of crustal structure variability on the inversion for the rupture process of the 2009 L'Aquila earthquake. We particularly assess the rupture model uncertainty related to one- and three-dimensional Earth models that are used to compute Green's functions. In doing so, we evaluate the role of using more realistic crustal structure in resolving the rupture model parameters. We apply Bayesian inference to quantitatively assess the characteristics of the space-time rupture evolution (peak slip-rate, rupture time, and rise time) in terms of posterior density functions. We find that the use of realistic 3D crustal structure, including topography and crustal heterogeneity improves the earthquake source imaging. We also investigate the sensitivity of rupture parameters with respect to the variations in crustal structure.

  18. Mental health in L'Aquila after the earthquake

    Directory of Open Access Journals (Sweden)

    Paolo Stratta

    2012-06-01

    Full Text Available INTRODUCTION: In the present work we describe the mental health condition of L'Aquila population in the aftermath of the earthquake in terms of structural, process and outcome perspectives. METHOD: Literature revision of the published reports on the L'Aquila earthquake has been performed. RESULTS: Although important psychological distress has been reported by the population, capacity of resilience can be observed. However if resilient mechanisms intervened in immediate aftermath of the earthquake, important dangers are conceivable in the current medium-long-term perspective due to the long-lasting alterations of day-to-day life and the disruption of social networks that can be well associated with mental health problems. CONCLUSIONS: In a condition such as an earthquake, the immediate physical, medical, and emergency rescue needs must be addressed initially. However training first responders to identify psychological distress symptoms would be important for mental health triage in the field.

  19. IASPEI PRESS RELEASE ON THE L’AQUILA SENTENCE

    Directory of Open Access Journals (Sweden)

    Article Editorial

    2015-10-01

    Full Text Available The Mw 6.3 earthquake, that occurred in L'Aquila, Central Italy on April 6, 2009, killed 309 people, 1500 citizens were injured, and 30000 people lost their homes. On October 22, 2012, an Italian court in L'Aquila convicted seven scientists for failing to adequately warn residents before the earthquake struck Central Italy. All are members of the National Great Risks Commission, and several are prominent Italian seismologists and disaster experts. They were accused of involuntary manslaughter, negligence and errors in the assessment of the earthquake precursors and sentenced to six years in prison and payment of monetary compensations to relatives of those killed and injured.

  20. Microstructures and deformation mechanisms in Opalinus Clay: insights from scaly clay from the Main Fault in the Mont Terri Rock Laboratory (CH)

    Science.gov (United States)

    Laurich, Ben; Urai, Janos L.; Nussbaum, Christophe

    2017-01-01

    The Main Fault in the shaly facies of Opalinus Clay is a small reverse fault formed in slightly overconsolidated claystone at around 1 km depth. The fault zone is up to 6 m wide, with micron-thick shear zones, calcite and celestite veins, scaly clay and clay gouge. Scaly clay occurs in up to 1.5 m wide lenses, providing hand specimens for this study. We mapped the scaly clay fabric at 1 m-10 nm scale, examining scaly clay for the first time using broad-ion beam polishing combined with scanning electron microscopy (BIB-SEM). Results show a network of thin shear zones and microveins, separating angular to lensoid microlithons between 10 cm and 10 µm in diameter, with slickensided surfaces. Our results show that microlithons are only weakly deformed and that strain is accumulated by fragmentation of microlithons by newly formed shear zones, by shearing in the micron-thick zones and by rearrangement of the microlithons.The scaly clay aggregates can be easily disintegrated into individual microlithons because of the very low tensile strength of the thin shear zones. Analyses of the microlithon size by sieving indicate a power-law distribution model with exponents just above 2. From this, we estimate that only 1 vol % of the scaly clay aggregate is in the shear zones.After a literature review of the hypotheses for scaly clay generation, we present a new model to explain the progressive formation of a self-similar network of anastomosing thin shear zones in a fault relay. The relay provides the necessary boundary conditions for macroscopically continuous deformation. Localization of strain in thin shear zones which are locally dilatant, and precipitation of calcite veins in dilatant shear fractures, evolve into complex microscale re-partitioning of shear, forming new shear zones while the microlithons remain much less deformed internally and the volume proportion of the µm-thick shear zones slowly increases. Grain-scale deformation mechanisms are microfracturing

  1. Modelado semiempírico de V923 Aquilae

    Science.gov (United States)

    Arias, M. L.; Cidale, L.; Ringuelet, A.

    V923 Aquilae is a Be shell star which shows emission in Balmer lines, cyclic V/R variations and variations in the near infrared region. In this work, we make a detailed study of its visual and ultraviolet spectrum. >From the analysis of the spectral lines, we obtain information about their forming regions (eg. electronic temperature and dimensions), which allow us to propose a semi-empirical model for the structure of the extended envelope of this star.

  2. Mechanisms for Generation of Near-Fault Ground Motion Pulses for Dip-Slip Faulting

    Science.gov (United States)

    Poiata, Natalia; Miyake, Hiroe; Koketsu, Kazuki

    2017-04-01

    We analyzed the seismological aspects of the near-fault ground motion pulses and studied the main characteristics of the rupture configuration that contribute to the pulse generation for dip-slip faulting events by performing forward simulations in broadband and low-frequency ranges for different rupture scenarios of the 2009 L'Aquila, Italy (M w 6.3) earthquake. The rupture scenarios were based on the broadband source model determined by Poiata et al. (Geophys J Int 191:224-242, 2012). Our analyses demonstrated that ground motion pulses affect spectral characteristics of the observed ground motions at longer periods, generating significantly larger seismic demands on the structures than ordinary records. The results of the rupture scenario simulations revealed the rupture directivity effect, the radial rupture propagation toward the site, and the focusing effect as the main mechanisms of the near-fault ground motion pulse generation. The predominance of one of these mechanisms depends on the location of the site relative to the causative fault plane. The analysis also provides the main candidate mechanisms for the worst-case rupture scenarios of pulse generation for the city of L'Aquila and, more generally, the hanging-wall sites located above the area of large slip (strong motion generation area).

  3. In connection with identification of VLF emissions before L'Aquila earthquake

    CERN Document Server

    Kachakhidze, M; Kachakhidze, N

    2012-01-01

    The present paper deals with an attempt to check up the theoretical model of self-generated seismo-electromagnetic oscillations of LAI system on the basis of retrospective data. Application of the offered simple model enables one to explain qualitatively the mechanism of VLF electromagnetic emission initiated in the process of an earthquake preparation. It is worth to pay attention to the fact that frequency changes from MHz to kHz in electromagnetic emission spectrum comes to a good agreement with avalanche-like unstable model of fault formation. L'Aquila earthquake taken as an example to isolate reliably the Earth VLF emission from the magnetospheric electromagnetic emission of the same frequency range, MHD criterion is offered together with geomagnetic activity indexes. On the basis of the considered three earthquakes, according to the opinion of authors the model of self-generated seismo-electromagnetic oscillations of the LAI system will enable us to approach the problem of resolution of earthquake predi...

  4. Efficacy of StaMPS technique for monitoring surface deformation in L'Aquila, Italy

    Science.gov (United States)

    Tiwari, A.; Dwivedi, R.; Narayan, A. B.; Dikshit, O.; Singh, A. K.

    2014-11-01

    This research work investigates the efficacy of the Stanford Method for Persistent Scatterer Interferometry (StaMPS) in measuring the surface deformation over the L'Aquila region, Italy just before an event of earthquake of magnitude Mw 6.3 by using seven descending Envisat C-Band ASAR images. The results show that the StaMPS technique successfully extracted sufficient number of Persistent Scatterers (PS) to derive a one dimensional (1D) time series displacement map which shows the deformation rates up to 59 mm/year in the satellite Line of Sight (LOS) direction and 50.8 mm/year in the direction opposite to the satellite LOS. Further, several deformation gradients are also observed from this map which indicate the occurrence of multiple crustal movement mechanism. Another dataset of 14 ASAR images is processed covering a time period before and after the earthquake in the study area to validate the results obtained by the previous dataset. We observed that the generated displacement map follows the deformation characteristics of the earlier displacement map in terms of magnitude and surface movement. We conclude that the generated displacement maps validate the presence of a normal fault mechanism with a tectonic process stretching in a NW-SE direction as predicted by earlier research studies.

  5. 3D Finite Element Modeling of the 2009 L'Aquila Earthquake Deformation Field

    Science.gov (United States)

    Volpe, M.; Casarotti, E.; Piersanti, A.

    2009-12-01

    The L'Aquila earthquake (Mw 6.3) occurred on April 6th at 01:32 UTC in the Central Appennines at a depth of about 9 km and was felt all over Central Italy. The main shock was preceded by a long seismic sequence started several months before and was followed by thousands of aftershocks, some of them with Mw>4. We built up a high resolution three-dimensional model, incorporating surface topography, which was discretized using 20-nodes brick elements. The element horizontal size is biased from 500 m to 2 km using the paving meshing algorithm in combination with an appropriate adaptive sizing function. A realistic rheology was introduced from a vp/vpvs travel time tomographic model. We computed the co-seismic deformation induced by the earthquake by means of a recently developed finite elements simulation tool, FEMSA (Finite Element Modeling for Seismic Applications). We used different seismic source models obtained from fault inversion of GPS measurements, joint inversion of strong motion and GPS data and from inversion of DInSAR displacements. The synthetic deformation patterns were compared with the experimental results in order to evaluate which source model better reconciles the data and quantify the trade off introduced by 1D simulations.

  6. Assessment of lead exposure in Spanish imperial eagle (Aquila adalberti) from spent ammunition in central Spain

    Science.gov (United States)

    Fernandez, Julia Rodriguez-Ramos; Hofle, Ursula; Mateo, Rafael; de Francisco, Olga Nicolas; Abbott, Rachel; Acevedo, Pelayo; Blanco, Juan-Manuel

    2011-01-01

    The Spanish imperial eagle (Aquila adalberti) is found only in the Iberian Peninsula and is considered one of the most threatened birds of prey in Europe. Here we analyze lead concentrations in bones (n = 84), livers (n = 15), primary feathers (n = 69), secondary feathers (n = 71) and blood feathers (n = 14) of 85 individuals collected between 1997 and 2008 in central Spain. Three birds (3.6%) had bone lead concentration > 20 (mu or u)g/g and all livers were within background lead concentration. Bone lead concentrations increased with the age of the birds and were correlated with lead concentration in rachis of secondary feathers. Spatial aggregation of elevated bone lead concentration was found in some areas of Montes de Toledo. Lead concentrations in feathers were positively associated with the density of large game animals in the area where birds were found dead or injured. Discontinuous lead exposure in eagles was evidenced by differences in lead concentration in longitudinal portions of the rachis of feathers.

  7. Influence of epistemic uncertainties on the slip distribution of continental earthquakes: application to the 2009 L'Aquila (Mw6.3) and 2016 Amatrice (Mw6.0) earthquakes, central Italy.

    Science.gov (United States)

    Ragon, T.; Sladen, A.; Bletery, Q.; Simons, M.; Magnoni, F.; Avallone, A.; Cavalié, O.; Vergnolle, M.

    2016-12-01

    The increased availability of InSAR observations now allows a quasi-systematic study of the finite-fault slip distribution of continental earthquakes with Mw > 6.0. These data are often complemented by near-fault GPS and seismic records. Despite this deluge of new data, independent studies still frequently result in significantly different inferences of subsurface fault slip. For example, published models for the well-studied 2009 Mw 6.3 earthquake of L'Aquila, Italy, have a maximum coseismic slip patch whose amplitude varies from 0.8 m to 2.3 m, with a centroid depth that varies between 5 and 15 km. Assuming that observational uncertainties are relatively well known (and appropriately accounted for), the discrepancies between inferred source models can be primarily attributed to epistemic uncertainties and the inherent non-uniqueness of inverse problem. Two potentially strong sources of epistemic uncertainties are the poor knowledge of the fault geometry and the elastic properties of the medium around the fault. Here, we explore the contribution of these various effects (non-uniqueness, uncertainties in the elastic properties and fault geometry) on inferences for the L'Aquila, 2009, and Amatrice, 2016, earthquakes. We investigate the non uniqueness of the inverse problem by performing a fully Bayesian analysis, which allows the exploration of the whole solution space of fault-slip models compatible with the data, within the range of both observational and epistemic uncertainties. While the estimation of uncertainties related to elastic properties has been implemented recently on finite-fault slip inversions, the evaluation of fault geometry uncertainty remains unexplored yet and thus could represent a significant issue. The L'Aquila and Amatrice earthquakes share many characteristics, but larger uncertainties yet remain on the geometry of the Amatrice event and on its local elastic structure. This work aims at improving our knowledge of these earthquakes through

  8. Influence of epistemic uncertainties on the slip distribution of continental earthquakes: application to the 2009 L'Aquila (Mw6.3) and 2016 Amatrice (Mw6.0) earthquakes, central Italy.

    Science.gov (United States)

    Ragon, Théa; Sladen, Anthony; Bletery, Quentin; Simons, Mark; Magnoni, Frederica; Avallone, Antonio; Cavalié, Olivier; Vergnolle, Mathilde

    2016-12-01

    The increased availability of InSAR observations now allows a quasi-systematic study of the finite-fault slip distribution of continental earthquakes with Mw > 6.0. These data are often complemented by near-fault GPS and seismic records. Despite this deluge of new data, independent studies still frequently result in significantly different inferences of subsurface fault slip. For example, published models for the well-studied 2009 Mw 6.3 earthquake of L'Aquila, Italy, have a maximum coseismic slip patch whose amplitude varies from 0.8 m to 2.3 m, with a centroid depth that varies between 5 and 15 km. Assuming that observational uncertainties are relatively well known (and appropriately accounted for), the discrepancies between inferred source models can be primarily attributed to epistemic uncertainties and the inherent non-uniqueness of inverse problem. Two potentially strong sources of epistemic uncertainties are the poor knowledge of the fault geometry and the elastic properties of the medium around the fault. Here, we explore the contribution of these various effects (non-uniqueness, uncertainties in the elastic properties and fault geometry) on inferences for the L'Aquila, 2009, and Amatrice, 2016, earthquakes. We investigate the non uniqueness of the inverse problem by performing a fully Bayesian analysis, which allows the exploration of the whole solution space of fault-slip models compatible with the data, within the range of both observational and epistemic uncertainties. While the estimation of uncertainties related to elastic properties has been implemented recently on finite-fault slip inversions, the evaluation of fault geometry uncertainty remains unexplored yet and thus could represent a significant issue. The L'Aquila and Amatrice earthquakes share many characteristics, but larger uncertainties yet remain on the geometry of the Amatrice event and on its local elastic structure. This work aims at improving our knowledge of these earthquakes through

  9. Lessons of L'Aquila for Operational Earthquake Forecasting

    Science.gov (United States)

    Jordan, T. H.

    2012-12-01

    The L'Aquila earthquake of 6 Apr 2009 (magnitude 6.3) killed 309 people and left tens of thousands homeless. The mainshock was preceded by a vigorous seismic sequence that prompted informal earthquake predictions and evacuations. In an attempt to calm the population, the Italian Department of Civil Protection (DPC) convened its Commission on the Forecasting and Prevention of Major Risk (MRC) in L'Aquila on 31 March 2009 and issued statements about the hazard that were widely received as an "anti-alarm"; i.e., a deterministic prediction that there would not be a major earthquake. On October 23, 2012, a court in L'Aquila convicted the vice-director of DPC and six scientists and engineers who attended the MRC meeting on charges of criminal manslaughter, and it sentenced each to six years in prison. A few weeks after the L'Aquila disaster, the Italian government convened an International Commission on Earthquake Forecasting for Civil Protection (ICEF) with the mandate to assess the status of short-term forecasting methods and to recommend how they should be used in civil protection. The ICEF, which I chaired, issued its findings and recommendations on 2 Oct 2009 and published its final report, "Operational Earthquake Forecasting: Status of Knowledge and Guidelines for Implementation," in Aug 2011 (www.annalsofgeophysics.eu/index.php/annals/article/view/5350). As defined by the Commission, operational earthquake forecasting (OEF) involves two key activities: the continual updating of authoritative information about the future occurrence of potentially damaging earthquakes, and the officially sanctioned dissemination of this information to enhance earthquake preparedness in threatened communities. Among the main lessons of L'Aquila is the need to separate the role of science advisors, whose job is to provide objective information about natural hazards, from that of civil decision-makers who must weigh the benefits of protective actions against the costs of false alarms

  10. The reconstruction of L’Aquila, ancients and new devices

    Directory of Open Access Journals (Sweden)

    Stefano Cecamore

    2015-12-01

    The use of the traditional anti-seismic devices witnesses the workforce awareness of the insufficient tensile strength resistance of the walls, but the typological and formal adaptation of the original Medieval and Renaissance building cells defines the building constructions as extremely complex and vulnerable compared to seismic activities further burdened by recent and misconstrued restoration project. The current planning choices primarily respond to psychological requests rather than to historical and aesthetic ones, furthermore, they are subject to a new predominant principle developed in the recent decade: the seismic safety. Keywords: L'Aquila, earthquake, safety, restoration, reinforcement

  11. The narrative epidemiology of L'Aquila 2009 earthquake.

    Science.gov (United States)

    Casacchia, M; Pollice, R; Roncone, R

    2012-03-01

    The authors describe their experience working and living in L'Aquila, where at 3.32 a.m., early in the morning of 6 April 2009, a 6.3 Richter magnitude earthquake caused serious damages to this 13th century town (with a population of 72 000 and a health district of 103 788), in the mountainous Abruzzo region and to several medieval hill villages in the surrounding areas: 309 residents were killed, over 1600 were injured, 66 000 residents were displaced, and, the centre of L'Aquila, the main historical and artistic centre of Abruzzo, was totally destroyed. Here is described the work done at the Psychiatric Unit of the General Hospital of L'Aquila and in the University. The Authors report the incidence rate of Acute Stress Disorder (ASD) in help-seekers (full ASD 4.9%, and partial ASD 39.3%), and of post-traumatic stress disorder (PTSD) found in different samples of population (range 12-37.5). The authors express their consideration about which real-world variables can reflect the population distress and the naturalistic process of recovery in such natural disasters. After the earthquake they hypothesize that a lot of residents had found their way to recover through 'writing, telling the story', by analogy with what narrative medicine asserts, thus estimating the positive effect of 'emotional disclosure' on health. A large number of materials (books, web-blogs, videos) were produced by residents and a database of memories was implemented. The suffering and struggle to recover in the aftermaths of a traumatic experience often yields remarkable transformations and positive growth. From this point of view, the authors underline the increased virtual relationships of residents through Facebook, to cope with the loss of previous social relationships, to get information about recreational opportunities, or to get organized for public events, despite their displacement. Many collective demonstrations were organized and showed the will to actively participate to the

  12. Crustal Anisotropy Beneath The Central Apennines (Italy) as revealed by the 2009 L'Aquila Seismic Sequence

    Science.gov (United States)

    Baccheschi, P.; Pastori, M.; Margheriti, L.; Piccinini, D.

    2014-12-01

    We perform a systematic analysis of the crustal anisotropic parameters, fast polarization direction (φ) and delay time (δt), of hundreds of earthquakes recorded during the 2009 L'Aquila seismic sequence, which occurred in the Central Apennines Neogene fold-and-thrust-belt. We benefit from the dense coverage of seismic stations operating in the area and from a catalogue of several accurate earthquakes locations to describe in detail the geometry of the anisotropic volume around the major active faults, providing new insights on the anisotropic structure beneath the L'Aquila area and surrounding region. The results show strong spatial variations in the φ and δt values, revealing the presence of anisotropic complexity in the area. At most of the stations φ are mainly oriented NW-SE (~N141°). This trend well matches both the strike of the nearby major active normal faults and the regional maximum horizontal compressive stress (sHmax). This is also in agreement with the main stress indicators, such as focal mechanisms and borehole breakouts. δt at single stations vary between 0.024-0.26 s, with average value of ~0.07s. Similar results could be explained by the presence of stress aligned microcracks or stress-opened fluid-filled cracks and fractures within the crustal layers, as suggested by the EDA model. Moreover, the sharp coherence between φ and the strike of major faults does not allow us to completely rule out the contribution from the structural anisotropy. Measurements obtained at the stations in the southeastern side of the study area show different anisotropic parameters. In this region φ do not appear parallel with either the strike of the local mapped faults or the sHmax direction, becoming oriented predominantly NE-SW. These stations also report the highest value of δt (up to 0.09 s). This results could be explained by the presence of a highly fractured and over-pressurized rock volumes, which causes the 90°-flips in φ and an increase in

  13. Structural damages of L'Aquila (Italy earthquake

    Directory of Open Access Journals (Sweden)

    H. Kaplan

    2010-03-01

    Full Text Available On 6 April 2009 an earthquake of magnitude 6.3 occurred in L'Aquila city, Italy. In the city center and surrounding villages many masonry and reinforced concrete (RC buildings were heavily damaged or collapsed. After the earthquake, the inspection carried out in the region provided relevant results concerning the quality of the materials, method of construction and the performance of the structures. The region was initially inhabited in the 13th century and has many historic structures. The main structural materials are unreinforced masonry (URM composed of rubble stone, brick, and hollow clay tile. Masonry units suffered the worst damage. Wood flooring systems and corrugated steel roofs are common in URM buildings. Moreover, unconfined gable walls, excessive wall thicknesses without connection with each other are among the most common deficiencies of poorly constructed masonry structures. These walls caused an increase in earthquake loads. The quality of the materials and the construction were not in accordance with the standards. On the other hand, several modern, non-ductile concrete frame buildings have collapsed. Poor concrete quality and poor reinforcement detailing caused damage in reinforced concrete structures. Furthermore, many structural deficiencies such as non-ductile detailing, strong beams-weak columns and were commonly observed. In this paper, reasons why the buildings were damaged in the 6 April 2009 earthquake in L'Aquila, Italy are given. Some suggestions are made to prevent such disasters in the future.

  14. Structural damages of L'Aquila (Italy) earthquake

    Science.gov (United States)

    Kaplan, H.; Bilgin, H.; Yilmaz, S.; Binici, H.; Öztas, A.

    2010-03-01

    On 6 April 2009 an earthquake of magnitude 6.3 occurred in L'Aquila city, Italy. In the city center and surrounding villages many masonry and reinforced concrete (RC) buildings were heavily damaged or collapsed. After the earthquake, the inspection carried out in the region provided relevant results concerning the quality of the materials, method of construction and the performance of the structures. The region was initially inhabited in the 13th century and has many historic structures. The main structural materials are unreinforced masonry (URM) composed of rubble stone, brick, and hollow clay tile. Masonry units suffered the worst damage. Wood flooring systems and corrugated steel roofs are common in URM buildings. Moreover, unconfined gable walls, excessive wall thicknesses without connection with each other are among the most common deficiencies of poorly constructed masonry structures. These walls caused an increase in earthquake loads. The quality of the materials and the construction were not in accordance with the standards. On the other hand, several modern, non-ductile concrete frame buildings have collapsed. Poor concrete quality and poor reinforcement detailing caused damage in reinforced concrete structures. Furthermore, many structural deficiencies such as non-ductile detailing, strong beams-weak columns and were commonly observed. In this paper, reasons why the buildings were damaged in the 6 April 2009 earthquake in L'Aquila, Italy are given. Some suggestions are made to prevent such disasters in the future.

  15. Quaternary Geology and Surface Faulting Hazard: Active and Capable Faults in Central Apennines, Italy

    Science.gov (United States)

    Falcucci, E.; Gori, S.

    2015-12-01

    The 2009 L'Aquila earthquake (Mw 6.1), in central Italy, raised the issue of surface faulting hazard in Italy, since large urban areas were affected by surface displacement along the causative structure, the Paganica fault. Since then, guidelines for microzonation were drew up that take into consideration the problem of surface faulting in Italy, and laying the bases for future regulations about related hazard, similarly to other countries (e.g. USA). More specific guidelines on the management of areas affected by active and capable faults (i.e. able to produce surface faulting) are going to be released by National Department of Civil Protection; these would define zonation of areas affected by active and capable faults, with prescriptions for land use planning. As such, the guidelines arise the problem of the time interval and general operational criteria to asses fault capability for the Italian territory. As for the chronology, the review of the international literature and regulatory allowed Galadini et al. (2012) to propose different time intervals depending on the ongoing tectonic regime - compressive or extensional - which encompass the Quaternary. As for the operational criteria, the detailed analysis of the large amount of works dealing with active faulting in Italy shows that investigations exclusively based on surface morphological features (e.g. fault planes exposition) or on indirect investigations (geophysical data), are not sufficient or even unreliable to define the presence of an active and capable fault; instead, more accurate geological information on the Quaternary space-time evolution of the areas affected by such tectonic structures is needed. A test area for which active and capable faults can be first mapped based on such a classical but still effective methodological approach can be the central Apennines. Reference Galadini F., Falcucci E., Galli P., Giaccio B., Gori S., Messina P., Moro M., Saroli M., Scardia G., Sposato A. (2012). Time

  16. Gravity-driven postseismic deformation following the Mw 6.3 2009 L’Aquila (Italy) earthquake

    Science.gov (United States)

    Albano, Matteo; Barba, Salvatore; Saroli, Michele; Moro, Marco; Malvarosa, Fabio; Costantini, Mario; Bignami, Christian; Stramondo, Salvatore

    2015-11-01

    The present work focuses on the postseismic deformation observed in the region of L’Aquila (central Italy) following the Mw 6.3 earthquake that occurred on April 6, 2009. A new, 16-month-long dataset of COSMO-SkyMed SAR images was analysed using the Persistent Scatterer Pairs interferometric technique. The analysis revealed the existence of postseismic ground subsidence in the mountainous rocky area of Mt Ocre ridge, contiguous to the sedimentary plain that experienced coseismic subsidence. The postseismic subsidence was characterized by displacements of 10 to 35 mm along the SAR line of sight. In the Mt Ocre ridge, widespread morphological elements associated with gravitational spreading have been previously mapped. We tested the hypothesis that the postseismic subsidence of the Mt Ocre ridge compensates the loss of equilibrium induced by the nearby coseismic subsidence. Therefore, we simulated the coseismic and postseismic displacement fields via the finite element method. We included the gravitational load and fault slip and accounted for the geometrical and rheological characteristics of the area. We found that the elastoplastic behaviour of the material under gravitational loading best explains the observed postseismic displacement. These findings emphasize the role of gravity in the postseismic processes at the fault scale.

  17. Gravity-driven postseismic deformation following the Mw 6.3 2009 L'Aquila (Italy) earthquake.

    Science.gov (United States)

    Albano, Matteo; Barba, Salvatore; Saroli, Michele; Moro, Marco; Malvarosa, Fabio; Costantini, Mario; Bignami, Christian; Stramondo, Salvatore

    2015-11-10

    The present work focuses on the postseismic deformation observed in the region of L'Aquila (central Italy) following the Mw 6.3 earthquake that occurred on April 6, 2009. A new, 16-month-long dataset of COSMO-SkyMed SAR images was analysed using the Persistent Scatterer Pairs interferometric technique. The analysis revealed the existence of postseismic ground subsidence in the mountainous rocky area of Mt Ocre ridge, contiguous to the sedimentary plain that experienced coseismic subsidence. The postseismic subsidence was characterized by displacements of 10 to 35 mm along the SAR line of sight. In the Mt Ocre ridge, widespread morphological elements associated with gravitational spreading have been previously mapped. We tested the hypothesis that the postseismic subsidence of the Mt Ocre ridge compensates the loss of equilibrium induced by the nearby coseismic subsidence. Therefore, we simulated the coseismic and postseismic displacement fields via the finite element method. We included the gravitational load and fault slip and accounted for the geometrical and rheological characteristics of the area. We found that the elastoplastic behaviour of the material under gravitational loading best explains the observed postseismic displacement. These findings emphasize the role of gravity in the postseismic processes at the fault scale.

  18. Natural Disasters and University Enrolment: Evidence from L'Aquila Earthquake

    OpenAIRE

    Cerqua, A.; Di Pietro, G.

    2015-01-01

    Although there are several studies looking at the effect of natural disasters on economic growth, less attention has been dedicated to their impact on educational outcomes, especially in more developed countries. We use the synthetic control method to examine how the L’Aquila earthquake affected subsequent enrolment at the local university. This issue has wide economic implications as the University of L’Aquila made a large contribution to the local economy before the earthquake. Our results ...

  19. Modified evisceration technique in a golden eagle (Aquila chrysaetos).

    Science.gov (United States)

    Dees, D Dustin; Knollinger, Amy M; MacLaren, Nicole E

    2011-09-01

    Two different modified techniques have been described for enucleation in raptors, including the transaural approach and the globe-collapsing procedure. This case report describes an alternative, modified evisceration procedure in a mature female Golden Eagle (Aquila chrysaetos). The advantages of this procedure are decreased anesthetic time, ease of procedure, decreased risk of excessive traction of the optic nerve, decreased intraoperative orbital trauma, and preservation of the natural symmetry of the head. The major disadvantage of this procedure is that it does not allow complete histologic examination of the globe. Patients with intraocular infection or neoplasia, or significant orbital disease may be poor candidates for this technique. © 2011 American College of Veterinary Ophthalmologists.

  20. Measuring A Truncated Disk in Aquila X-1

    CERN Document Server

    King, Ashley L; Miller, Jon M; Chenevez, Jerome; Barret, Didier; Boggs, Steven E; Chakrabarty, Deepto; Christensen, Finn E; Craig, William W; Furst, Felix; Hailey, Charles J; Harrison, Fiona A; Parker, Michael L; Stern, Daniel; Romano, Patrizia; Walton, Dominic J; Zhang, William W

    2016-01-01

    We present NuSTAR and Swift observations of the neutron star Aquila X-1 during the peak of its July 2014 outburst. The spectrum is soft with strong evidence for a broad Fe K\\alpha line. Modeled with a relativistically broadened reflection model, we find that the inner disk is truncated with an inner radius of 15+/-3 R_G. The disk is likely truncated by either the boundary layer and/or a magnetic field. Associating the truncated inner disk with pressure from a magnetic field gives an upper limit of B<5+/-2x10^8G. Although the radius is truncated far from the stellar surface, material is still reaching the neutron star surface as evidenced by the X-ray burst present in the t NuSTAR observation.

  1. High-resolution seismic reflection and refraction imaging across the epicentral area of the 2009, Mw 6.1 Aquila (Italy) earthquake.

    Science.gov (United States)

    Bruno, Pier Paolo G.; Villani, Fabio; Improta, Luigi; Castiello, Antonio; Pucci, Stefano; Civico, Riccardo; Pantosti, Stefania

    2017-04-01

    We present for the first time the results of high-resolution seismic reflection profiling aimed at imaging the shallow structure of Paganica and Bazzano Quaternary sub-basins across the shallow segments of the Paganica-S. Demetrio Fault, which has been indicated as the causative fault of the 6th April 2009 (Mw 6.1) L'Aquila earthquake (central Italy). The seismic data were collected along five dense and partly overlapping wide-aperture profiles, which run SW-NE for a total length of 6 km, mostly in the hanging wall of the Paganica-S. Demetrio Fault. To evaluate the optimal seismic reflection imaging strategy, we applied three different processing techniques to the dense, wide-aperture acquired data: a conventional CMP reflection processing; pre-stack depth migration (PSDM); and finally the Common-Reflection-Surface (CRS) stack technique. PSDM has proven capable of overcoming many of the typical drawbacks of CMP processing in the presence of complex subsurface velocity distributions. However, PSDM is highly sensitive to the accuracy of the background velocity model. Despite the use of an acquisition geometry effective for refraction tomography (e.g. dense wide-aperture), we were able to estimate a high-resolution background tomographic model suitable for migration purpose for Bazzano profile, whereas this was not the case for Paganica profile, due to greater structural complexity and a higher level of ambient noise. In these settings, the data-driven and velocity-independent CRS method provided a feasible alternative for seismic imaging in Paganica sub-basin. Integration of reflection seismology with refraction tomography and with new surface, paleoseismological and borehole data during interpretation provides new insights on the shallow architecture of the 2009 Mw 6.1 L'Aquila earthquake fault-system and related basins. Bazzano sub-basin is about 50-100 m deeper than Paganica sub-basin. The latter is offset by a large number of NE and SW-dipping faults affecting

  2. Structure of a normal seismogenic fault zone in carbonates: The Vado di Corno Fault, Campo Imperatore, Central Apennines (Italy)

    Science.gov (United States)

    Demurtas, Matteo; Fondriest, Michele; Balsamo, Fabrizio; Clemenzi, Luca; Storti, Fabrizio; Bistacchi, Andrea; Di Toro, Giulio

    2016-09-01

    The Vado di Corno Fault Zone (VCFZ) is an active extensional fault cutting through carbonates in the Italian Central Apennines. The fault zone was exhumed from ∼2 km depth and accommodated a normal throw of ∼2 km since Early-Pleistocene. In the studied area, the master fault of the VCFZ dips N210/54° and juxtaposes Quaternary colluvial deposits in the hangingwall with cataclastic dolostones in the footwall. Detailed mapping of the fault zone rocks within the ∼300 m thick footwall-block evidenced the presence of five main structural units (Low Strain Damage Zone, High Strain Damage Zone, Breccia Unit, Cataclastic Unit 1 and Cataclastic Unit 2). The Breccia Unit results from the Pleistocene extensional reactivation of a pre-existing Pliocene thrust. The Cataclastic Unit 1 forms a ∼40 m thick band lining the master fault and recording in-situ shattering due to the propagation of multiple seismic ruptures. Seismic faulting is suggested also by the occurrence of mirror-like slip surfaces, highly localized sheared calcite-bearing veins and fluidized cataclasites. The VCFZ architecture compares well with seismological studies of the L'Aquila 2009 seismic sequence (mainshock MW 6.1), which imaged the reactivation of shallow-seated low-angle normal faults (Breccia Unit) cut by major high-angle normal faults (Cataclastic Units).

  3. Shear wave splitting of the 2009 L'Aquila seismic sequence: fluid saturated microcracks and crustal fractures in the Abruzzi region (Central Apennines, Italy)

    Science.gov (United States)

    Baccheschi, P.; Pastori, M.; Margheriti, L.; Piccinini, D.

    2016-03-01

    The Abruzzi region is located in the Central Apennines Neogene fold-and-thrust belt and has one of the highest seismogenic potential in Italy, with high and diffuse crustal seismicity related to NE-SW oriented extension. In this study, we investigate the detailed spatial variation in shear wave splitting providing high-resolution anisotropic structure beneath the L'Aquila region. To accomplish this, we performed a systematic analysis of crustal anisotropic parameters: fast polarization direction (ϕ) and delay time (δt). We benefit from the dense coverage of seismic stations operating in the area and from a catalogue of several accurate earthquake locations of the 2009 L'Aquila seismic sequence, related to the Mw 6.1 2009 L'Aquila main shock, to describe in detail the geometry of the anisotropic volume around the active faults that ruptured. The spatial variations both in ϕ and δt suggest a complex anisotropic structure beneath the region caused by a combination of both structural- and stress-induced mechanisms. The average ϕ is NNW-SSE oriented (N141°), showing clear similarity both with the local fault strike and the SHmax. In the central part of the study area fast axes are oriented NW-SE, while moving towards the northeastern and northwestern sectors the fast directions clearly diverge from the general trend of NW-SE and rotate accordingly to the local fault strikes. The above-mentioned fault-parallel ϕ distribution suggests that the observed anisotropy is mostly controlled by the local fault-related structure. Toward the southeast fast directions become orthogonal both to strike of the local mapped faults and to the SHmax. Here, ϕ are predominantly oriented NE-SW; we interpret this orientation as due to the presence of a highly fractured and overpressurized rock volume which should be responsible of the 90° flips in ϕ and the increase in δt. Another possible mechanism for NE-SW orientation of ϕ in the southeastern sector could be ascribed to the

  4. Rare event simulation for dynamic fault trees

    NARCIS (Netherlands)

    Ruijters, Enno Jozef Johannes; Reijsbergen, D.P.; de Boer, Pieter-Tjerk; Stoelinga, Mariëlle Ida Antoinette

    2017-01-01

    Fault trees (FT) are a popular industrial method for reliability engineering, for which Monte Carlo simulation is an important technique to estimate common dependability metrics, such as the system reliability and availability. A severe drawback of Monte Carlo simulation is that the number of

  5. Fault Estimation

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2002-01-01

    This paper presents a range of optimization based approaches to fault diagnosis. A variety of fault diagnosis prob-lems are reformulated in the so-called standard problem setup introduced in the literature on robust control. Once the standard problem formulations are given, the fault diagnosis pr...... problems can be solved by standard optimization tech-niques. The proposed methods include: (1) fault diagnosis (fault estimation, (FE)) for systems with model uncertainties; (2) FE for systems with parametric faults, and (3) FE for a class of nonlinear systems.......This paper presents a range of optimization based approaches to fault diagnosis. A variety of fault diagnosis prob-lems are reformulated in the so-called standard problem setup introduced in the literature on robust control. Once the standard problem formulations are given, the fault diagnosis...

  6. Postseismic Viscoelastic Relaxation Following the L'Aquila 2009 Earthquake: Implications for Lithospheric Rheology of the Apennines

    Science.gov (United States)

    Silverii, F.; D'Agostino, N.; Metois, M.

    2014-12-01

    In this work we use GPS data to study the postseismic viscoelastic relaxation related to the MW 6.3 normal faulting earthquake that struck the city of L'Aquila (Central Apennines, Italy) on April 6, 2009. Only a limited number of normal-faulting earthquakes have geodetic measurements of viscoelastic relaxation and there is limited knowledge of the viscosity structure of the lower crust/upper mantle in the Central Appennines. Since this region is currently experiencing active extension that gives rise to normal-faulting seismicity, the estimation of the typical relaxation time of the region is of great interest for interseismic strain-rate estimations and to better understand how extension is accommodated beneath the upper seismogenic crust. GPS data are processed by using GIPSY/OASIS software. Particular care has been taken to estimate and correct for the interseismic deformation and the early afterslip deformation, well documented by GPS and InSAR (D'Agostino et al., 2012). A particularly interesting signal observed in the time series is related to hydrological loading with seasonal and multi-annual periodicities. Here we present the preliminary results of the comparison between about 5 years of postseismic deformation recorded at permanent GPS stations, and the surface deformation expected running different viscoelastic models in order to estimate best-fit rheological parameters. Forward models are generated by means of the PSCMP/PSGRN code (Wang et al. 2006). Preliminary results will be presented and possible implications for the mechanism of active crustal extension in general and of the Apennines in particular, will be discussed.

  7. Effects of L'Aquila earthquake on the prescribing pattern of antidepressant and antipsychotic drugs.

    Science.gov (United States)

    Trifirò, Gianluca; Italiano, Domenico; Alibrandi, Angela; Sini, Giovanna; Ferrajolo, Carmen; Capuano, Annalisa; Spina, Edoardo; Rossi, Alessandro; L'Aquila group

    2013-12-01

    Natural disasters provoke an increase in mental and medical disorders in survivors. Monitoring drug prescription changes after natural disasters can provide an indirect evaluation of trauma impact in the population. Moreover, it could be useful to both identify risk categories that require special assistance and assess possible drug abuse or misuse. To assess the effects of earthquake that occurred on April 6, 2009 on the use of antidepressant and antipsychotic drugs in the province of L'Aquila. General population of L'Aquila and Caserta provinces from Southern Italy. In a retrospective, drug utilization study we identified all the persons who received at least one dispensing of antidepressant and/or antipsychotic drugs during the period April 1st, 2008-March 31st, 2010. The monthly prevalence of use of these drugs, 1 year prior and after the date of earthquake in L'Aquila was compared between the two provinces, L'Aquila and Caserta. All the analyses were stratified by age groups, gender and drug classes. We observed an increase in the use of antipsychotic drugs and, to lesser extent, of antidepressant agents (mostly typicals and tryciclics, respectively) in the first 2 months after the earthquake in L'Aquila but not in Caserta. This increase was almost two-fold higher in women older than 75 years. After the first 2 months from the earthquake, the use of antidepressants and antipsychotics was stabilized at the pre-earthquake levels in L'Aquila. The earthquake determined a short-term increase in the use of antipsychotics (mostly haloperidol and promazine) and, to lesser extent, of antidepressants (i.e. tryciclics), especially in older women of L'Aquila.

  8. Gravity driven and tectonic post-seismic deformation of the April 6 2009 L'Aquila Earthquake detected by Cosmo-SkyMed DInSAR

    Science.gov (United States)

    Moro, M.; Albano, M.; Bignami, C.; Malvarosa, F.; Costantini, M.; Saroli, M.; Barba, S.; Falco, S.; Stramondo, S.

    2014-12-01

    The present work focuses on the analysis of post-seismic surface deformation detected in the area of L'Aquila, Central Italy, after the strong earthquake that hit the city and the surrounding villages on April 6th, 2009. The analysis has been carried out thanks to a new dataset of SAR COSMO-SkyMed images covering a time span of 480 days after the mainshock, with the adoption of the Persistent Scatterer Pairs (PSP) approach. This method allows the estimation of surface deformations by exploiting the SAR images at full resolution. In the investigated area two patterns of subsidence have been identified reaching a maximum value of 45 mm in the northeast area of the L'Aquila town. Here the subsidence is mainly ascribable to the post seismic slip release of the Paganica fault and it does not coincide with the maximum measured coseismic subsidence. The time series of the ground deformations also reveal that a large amount of deformation is released in the first three months after the main shock. The second pattern of deformation is centered on the Mt. Ocre ridge, where a detailed photogeological analysis allowed us to identify widespread evidence of morphological elements associated with Deep-seated gravitational slope deformation (DGSD). In particular geomorphologic analyses show evidences of lateral spread DGSD-type features, characterized by the tectonic superimposition of carbonatic sequences and transitional pelagic deposits. In this sector, the observed deformation is ascribable not only to the afterslip of the Paganica fault, but also to a gravitative cause. In order to confirm or reject such hypothesis a 2D numerical finite element models considering two cross sections over the Mt. Ocre ridge has been performed. The coseismic and postseimic deformations have been simulated numerically, considering an elastic-perfectly plastic rheology for the constituent rocks. First results show that most of the postseismic deformation is ascribable to the plastic deformation

  9. Quick moment tensor solution of the 2009 April 6, L'Aquila, Italy earthquake%2009年4月6日意大利拉奎拉(L'Aquila)地震快速矩张量解

    Institute of Scientific and Technical Information of China (English)

    刘超; 许力生; 陈运泰

    2009-01-01

    An Mw6.4 earthquake occurred in L'Aquila, central Italy at 1:32:42 UTC, April 6, 2009. We quickly obtained the moment tensor solution of the earthquake by inverting the P waveforms of broadband recordings from the GSN stations using the quick technique of moment tensor inversion, and further in-ferred that the nodal plane of strike 132°, dip 53°, rake -103° is the seismogen-ic fault.%2009年4月6日1点32分42秒协调世界时(UTC),在意大利中部地区发生了Mw6.4地震.作者利用矩张量快速反演技术,通过反演全球台网的宽频带P波波形得到了这次地震的矩张量解,并判断走向132°、倾角53°、滑动角-103°的节面是地震发生的断层面.

  10. The normal electrocardiogram of conscious golden eagles (Aquila chrysaetos).

    Science.gov (United States)

    Hassanpour, Hossein; Moghaddam, Abdol Karim Zamani; Bashi, Mehdi Cheraghchi

    2010-09-01

    The aim of this study was to describe the normal electrocardiographic patterns and values in conscious golden eagles (Aquila chrysaetos). The standard bipolar and augmented unipolar limb leads' electrocardiograms were recorded in the golden eagles. The waveforms were analyzed in all leads at 50 mm/sec and at 10 mm = 1 mV to determine P, PR (segment and interval), QRS, ST, and QT durations and P, net QRS complex, and T amplitudes. The polarity of each waveform was tabulated in all leads. The mean electrical axis for the frontal plane was calculated using standard bipolar leads II and III. The mean heart rate was 346.7 +/- 14.29 beats/min. The P wave was predominantly positive in standard bipolar leads I and II and augmented unipolar limb leads aVL and aVF. The dominant pattern ofwaveforms of the QRS complexes were QS in leads I, II, III, and aVF, whereas in leads aVR and aVL, the pattern was always R. The T wave was slightly positive in leads I, II, and aVF. The average value of the heart mean electrical axis was -85.9 +/- 7.50 degrees. Establishment of normal electrocardiogram values will facilitate a better understanding of electrocardiographic changes seen in many avian diseases.

  11. Biological Anomalies around the 2009 L'Aquila Earthquake.

    Science.gov (United States)

    Fidani, Cristiano

    2013-08-06

    The April 6, 2009 L'Aquila earthquake was the strongest seismic event to occur in Italy over the last thirty years with a magnitude of M = 6.3. Around the time of the seismic swarm many instruments were operating in Central Italy, even if not dedicated to biological effects associated with the stress field variations, including seismicity. Testimonies were collected using a specific questionnaire immediately after the main shock, including data on earthquake lights, gas leaks, human diseases, and irregular animal behavior. The questionnaire was made up of a sequence of arguments, based upon past historical earthquake observations and compiled over seven months after the main shock. Data on animal behavior, before, during and after the main shocks, were analyzed in space/time distributions with respect to the epicenter area, evidencing the specific responses of different animals. Several instances of strange animal behavior were observed which could causally support the hypotheses that they were induced by the physical presence of gas, electric charges and electromagnetic waves in atmosphere. The aim of this study was to order the biological observations and thereby allow future work to determine whether these observations were influenced by geophysical parameters.

  12. Strong foreshock signal preceding the L'Aquila (Italy earthquake (Mw 6.3 of 6 April 2009

    Directory of Open Access Journals (Sweden)

    G. Minadakis

    2010-01-01

    Full Text Available We used the earthquake catalogue of INGV extending from 1 January 2006 to 30 June 2009 to detect significant changes before and after the 6 April 2009 L'Aquila mainshock (Mw=6.3 in the seismicity rate, r (events/day, and in b-value. The statistical z-test and Utsu-test were applied to identify significant changes. From the beginning of 2006 up to the end of October 2008 the activity was relatively stable and remained in the state of background seismicity (r=1.14, b=1.09. From 28 October 2008 up to 26 March 2009, r increased significantly to 2.52 indicating weak foreshock sequence; the b-value did not changed significantly. The weak foreshock sequence was spatially distributed within the entire seismogenic area. In the last 10 days before the mainshock, strong foreshock signal became evident in space (dense epicenter concentration in the hanging-wall of the Paganica fault, in time (drastic increase of r to 21.70 events/day and in size (b-value dropped significantly to 0.68. The significantly high seismicity rate and the low b-value in the entire foreshock sequence make a substantial difference from the background seismicity. Also, the b-value of the strong foreshock stage (last 10 days before mainshock was significantly lower than that in the aftershock sequence. Our results indicate the important value of the foreshock sequences for the prediction of the mainshock.

  13. The donor of Aquila X-1 revealed by high-angular resolution near-infrared spectroscopy

    Science.gov (United States)

    Mata Sánchez, D.; Muñoz-Darias, T.; Casares, J.; Jiménez-Ibarra, F.

    2017-01-01

    The low-mass X-ray binary Aquila X-1 is one of the most active neutron star X-ray transients. Despite its relatively bright quiescent optical counterpart, the detection of its companion has been hampered by the presence of a nearby interloper star. Using the Spectrograph for INtegral Field Observations in the Near Infrared (SINFONI) on the Very Large Telescope-8.2m telescope, we unambiguously single out Aquila X-1 from the interloper. Phase-resolved near-infrared spectroscopy reveals absorption features from a K4 ± 2 companion star moving at a projected velocity of K2 = 136 ± 4 km s- 1. We here present the first dynamical solution and associated fundamental parameters of Aquila X-1, imposing new constraints on the orbital inclination (36° star transient.

  14. L'Aquila's reconstruction challenges: has Italy learned from its previous earthquake disasters?

    Science.gov (United States)

    Ozerdem, Alpaslan; Rufini, Gianni

    2013-01-01

    Italy is an earthquake-prone country and its disaster emergency response experiences over the past few decades have varied greatly, with some being much more successful than others. Overall, however, its reconstruction efforts have been criticised for being ad hoc, delayed, ineffective, and untargeted. In addition, while the emergency relief response to the L'Aquila earthquake of 6 April 2009-the primary case study in this evaluation-seems to have been successful, the reconstruction initiative got off to a very problematic start. To explore the root causes of this phenomenon, the paper argues that, owing to the way in which Italian Prime Minister Silvio Berlusconi has politicised the process, the L'Aquila reconstruction endeavour is likely to suffer problems with local ownership, national/regional/municipal coordination, and corruption. It concludes with a set of recommendations aimed at addressing the pitfalls that may confront the L'Aquila reconstruction process over the next few years.

  15. The donor of Aquila X-1 revealed by high angular resolution near-infrared spectroscopy

    CERN Document Server

    Sánchez, D Mata; Casares, J; Jiménez-Ibarra, F

    2016-01-01

    The low mass X-ray binary Aquila X-1 is one of the most active neutron star X-ray transients. Despite it has a relatively bright quiescent optical counterpart, the detection of its companion has been hampered by the presence of a nearby interloper star. Using the infrared integral field spectrograph SINFONI on the VLT-8.2m telescope, we unambiguously single out Aquila X-1 from the interloper. Phase-resolved near infrared spectroscopy reveals absorption features from a K4 +- 2 companion star moving at a projected velocity of K_2= 139 +- 4 km/s. We here present the first dynamical solution and associated fundamental parameters of Aquila X-1, imposing new constraints to the orbital inclination (36 deg < i < 49 deg) and the distance (d = 6 +- 2 kpc) to this prototypical neutron star transient.

  16. Annotazioni Critiche su Aquila e Priscilla, il Titulius Priscae e le Catacombe di Priscilla a Roma

    Directory of Open Access Journals (Sweden)

    Ilaria Ramelli

    2000-01-01

    Full Text Available The article proposes an analysis of the tradition concerning Aquila and Priscilla; the titulus Priscae in Rome is probably connected not with Aquila's wife, but with the later Virgin and Martyr St. Frisca. We don't know whether the Aquila and the Priscilla who were buried in the catacombs of Priscilla can be identified with St. Paul's friends, but it is sure that these catacombs were possessed —at a very early date— by the Acilii Glabriones. They contain inscriptions from the llnd century AD onward, but perhaps there were Christian members of the family already in the Ist century: one of the Acilii Glabriones was a Román senator who was put to death during Domitian's persecution; and it is highiy probable that he was a Christian.L'étude analyse en premier lieu la tradition sur Aquila ef Priscille. Probablement le titulus Priscae est lié non avec la femme d'Aquila, mais avec la plus tarde Vierge et l\\/lartyr Pasque. Nous ne savons pas si les Aquila et Priscilla ensevelis dans le cimetiére de Priscilla sont identifiables avec les amis de saint Paul, mais il est bien sur que le cimetiére était propriété des Acilii Glabriones des une tres haute antiquité. Dans le méme cimetiére ont efe découvertes plusleurs inscriptions du líeme siécle apr. J.-C, peut-étre ainsi du ler. Á la fin du ler siécle apr. J.-C. un Acilius Glabrio, senateur romain, fut condamné a mort par Domitien, et tres probablement il était chrétien.

  17. Unipolar magnetic field pulses as transient signals prior to the 2009 Aquila earthquake shock

    CERN Document Server

    Nenovski, Petko

    2016-01-01

    Unipolar pre-seismic magnetic field pulses have been observed first by Bleier et al. (2009) and Villante et al. (2010) and Nenovski et al. (2013). In the present study a detailed analysis of the pulses is conducted looking for signatures of transient signals similar to that recorded at the 2009 Aquila earthquake main shock (Nenovski, 2015). Various magnetic field data around the Aquila earthquake provide an instrumental basis for such an analysis. In addition to fluxgate magnetometer data (already examined in previous studies), overhauser magnetometer data are involved. The result is a detection and discrimination of transient signals of diffusive form that appear prior to the earthquake main shock.

  18. Community mental health service utilization after the L'Aquila earthquake.

    Science.gov (United States)

    Stratta, Paolo; de Cataldo, Stefano; Bonanni, Roberto L; Rossi, Alessandro

    2015-05-01

    This study investigated the use of the facilities for the mental health by the population affected by the L'Aquila (Italy) 2009 earthquake. The data about the activities of the Mental Health Centre of L'Aquila during the years from 2008 to 2010 were obtained by the service Information System. In the months following the event the percentage of referrals was reduced. Failure to use specialized facilities after disasters should not be seen as reassuring. It is conceivable that a relevant rate of frank or sub-threshold psychopathology is present that the traditional mental health facilities may not be able to intercept.

  19. PURIFICATION AND CHARACTERIZATION OF RIBOFLAVIN BINDING PROTEIN FROM THE EGG WHITE OF EAGLE (AQUILA HASTATE

    Directory of Open Access Journals (Sweden)

    Madhkar Rao Kudle et al.

    2012-01-01

    Full Text Available Riboflavin binding protein (RfBP was isolated from the eggs of Aquila hastate (eagle. The protein was purified in two steps, DEAE – Sepharose ion exchange chromatography and gelfilteration on Sephadex G-100. The holoprotein had an absorption spectrum characteristic of flavoproteins. The purity of the protein was judged by SDS-PAGE technique. A single band on the slab and cylindrical gel revealed that the protein was pure comparison of the mobility of RfBP with that of the standard molecular weight marker proteins suggested that RfBP from the egg white of Aquila hastate had a molecular weight close to 29 Kd.

  20. Spatio-temporal variations of stress drop in and around the asperity of the Mw 6.1, 6 April 2009 L'Aquila earthquake.

    Science.gov (United States)

    Calderoni, G.

    2015-12-01

    We investigate the variability of Brune stress drop in the normal fault system activated by the Mw 6.1 L'Aquila earthquake in the complex tectonic setting of the central Apennine. We re-analyze the dataset used by Calderoni et al. [2013], augmented by additional earthquakes and additional records at closer distance stations. We refine the EGF method used by Calderoni et al. [2013] applying more restrictive criteria in the selection of the EGF events and removing outliers based on statistical criteria. We focus on spatio-temporal variations in the Paganica fault before the mainshock. Using 51 earthquakes (9 foreshocks, the mainshock, and 42 aftershocks), we show that, after the Mw 4.1 largest foreshock of 30 March 2009, the Brune stress drop goes down to the lowest values (0.4 MPa). This largest foreshock was indicated as a marker for the onset of the temporal variations in efficiency of fault-zone guided waves (Calderoni et al., 2015) and other independent seismic parameters such as the b value [Papadopoulos et al., 2010; Sugan et al., 2014], and the P-to-S wave velocity ratio [Di Luccio et al., 2010; Lucente et al., 2010]. The low values of stress drop after the Mw 4.1 foreshock are consistent with the increase of pore pressure invoked by other authors to explain the increase of the Vp/Vs ratio and the decrease of Vs in the damage fault zone. In contrast, immediate foreshocks occurring a few hours before the mainshock very close to its nucleation are characterized by the highest values observed for foreshocks (≈5 MPa). These high stress drop foreshocks are located in the fault patch where a low b value anomaly indicates highly stressed rock before the main shock rupture [Sugan et al., 2014]. These results provide further evidence to previous observations before major earthquakes suggesting that stress drop variations can provide insight into the preparatory phase of impending earthquakes.

  1. Microstructural investigations on carbonate fault core rocks in active extensional fault zones from the central Apennines (Italy)

    Science.gov (United States)

    Cortinovis, Silvia; Balsamo, Fabrizio; Storti, Fabrizio

    2017-04-01

    The study of the microstructural and petrophysical evolution of cataclasites and gouges has a fundamental impact on both hydraulic and frictional properties of fault zones. In the last decades, growing attention has been payed to the characterization of carbonate fault core rocks due to the nucleation and propagation of coseismic ruptures in carbonate successions (e.g., Umbria-Marche 1997, L'Aquila 2009, Amatrice 2016 earthquakes in Central Apennines, Italy). Among several physical parameters, grain size and shape in fault core rocks are expected to control the way of sliding along the slip surfaces in active fault zones, thus influencing the propagation of coseismic ruptures during earthquakes. Nevertheless, the role of grain size and shape distribution evolution in controlling the weakening or strengthening behavior in seismogenic fault zones is still not fully understood also because a comprehensive database from natural fault cores is still missing. In this contribution, we present a preliminary study of seismogenic extensional fault zones in Central Apennines by combining detailed filed mapping with grain size and microstructural analysis of fault core rocks. Field mapping was aimed to describe the structural architecture of fault systems and the along-strike fault rock distribution and fracturing variations. In the laboratory we used a Malvern Mastersizer 3000 granulometer to obtain a precise grain size characterization of loose fault rocks combined with sieving for coarser size classes. In addition, we employed image analysis on thin sections to quantify the grain shape and size in cemented fault core rocks. The studied fault zones consist of an up to 5-10 m-thick fault core where most of slip is accommodated, surrounded by a tens-of-meters wide fractured damage zone. Fault core rocks consist of (1) loose to partially cemented breccias characterized by different grain size (from several cm up to mm) and variable grain shape (from very angular to sub

  2. Aid effectiveness: How is the L’Aquila food security initiative doing?:

    OpenAIRE

    2014-01-01

    This paper uses case studies of Bangladesh, Ghana, Rwanda, and Senegal to assess the degree to which the L’Aquila Food Security Initiative (AFSI) has been implemented within the framework of managing for development results (MfDR) and to evaluate progress in various outcomes, including economic governance, agricultural growth, poverty, and food and nutrition security (FNS).

  3. New challenges for seismology and decision makers after L'Aquila trial

    Science.gov (United States)

    Marzocchi, Warner

    2013-04-01

    On 22 October seven experts who attended a Major Risk Committee meeting were sentenced to six years in prison on charges of manslaughter for underestimating the risk before the devastating 6.3-magnitude earthquake that struck the hillside city of L'Aquila on 6 April 2009, which caused more than 300 deaths. The earthquake followed a sequence of seismic events that started at the beginning of the year, with the largest shock - a 4.2-magnitude earthquake - occurring on 30 March. A day later, the seven experts met in L'Aquila; the minutes of the meeting, which were released after the quake, contained three main conclusions: that earthquakes are not predictable in a deterministic sense; that the L'Aquila region has the highest seismic hazard in Italy; and that the occurrence of a large earthquake in the short term was unlikely. There is not doubt that this trial will represent an important turning point for seismologists, and more in general for scientists who serve as advisors for public safety purposes. Here, starting from the analysis of the accusations made by the prosecutor and a detailed scientific appraisal of what happened, we try to figure out how seismology can evolve in order to be more effective in protecting people, and (possibly) avoiding accusations like the ones who characterize the L'Aquila trial. In particular, we discuss (i) the principles of the Operational Earthquake Forecasting that were put forward by an international Commission on Earthquake Forecasting (ICEF) nominated after L'Aquila earthquake, (ii) the ICEF recommendations for Civil Protection, and (iii) the recent developments in this field in Italy. Finally, we also explore the interface between scientists and decision makers, in particular in the framework of making decisions in a low probability environment.

  4. The 2009 L’Aquila earthquake coseismic rupture: open issues and new insights from 3D finite element inversion of GPS, InSAR and strong motion data

    Directory of Open Access Journals (Sweden)

    Manuela Volpe

    2015-06-01

    Full Text Available We present a Finite Element inverse analysis of the static deformation field for the Mw= 6.3, 2009 L’Aquila earthquake, in order to infer the rupture slip distribution on the fault plane. An univocal solution for the rupture slip distribution has not been reached yet with negative impact for reliable hazard scenarios in a densely populated area. In this study, Finite Element computed Green’s functions were implemented in a linear joint inversion scheme of geodetic (GPS and InSAR and seismological (strong motion coseismic deformation data. In order to fully exploit the informative power of our dense dataset and to honor the complexities of the real Earth, we implemented an optimized source model, represented by a fault plane subdivided in variable size patches, embedded in a high-resolution realistic three-dimensional model of the Apenninic seismo-tectonic setting, accounting for topographic reliefs and rheological heterogeneities deduced from local tomography. We infer that the investigated inversion domain contains two minima configurations in the solution space, i.e. a single- and a double-patch slip distribution, which are almost equivalent, so that the available datasets and numerical models are not able to univocally discriminate between them. Nevertheless our findings suggest that a two high-slip patch pattern is slightly favoured.

  5. The LVD signals during the early-mid stages of the L'Aquila seismic sequence and the radon signature of some aftershocks of moderate magnitude.

    Science.gov (United States)

    Cigolini, C; Laiolo, M; Coppola, D

    2015-01-01

    The L'Aquila seismic swarm culminated with the mainshock of April 6, 2009 (ML = 5.9). Here, we report and analyze the Large Volume Detector (LVD, used in neutrinos research) low energy traces (∼0.8 MeV), collected during the early-mid stages of the seismic sequence, together with the data of a radon monitoring experiment. The peaks of LVD traces do not correlate with the evolution and magnitude of earthquakes, including major aftershocks. Conversely, our radon measurements obtained by utilizing three automatic stations deployed along the regional NW-SE faulting system, seem to be, in one case, more efficient. In fact, the timeseries collected on the NW-SE Paganica fracture recorded marked variations and peaks that occurred during and prior moderate aftershocks (with ML > 3). The Paganica monitoring station (PGN) seems to better responds to active seismicity due to the fact that the radon detector was placed directly within the bedrock of an active fault. It is suggested that future networks for radon monitoring of active seismicity should preferentially implement this setting.

  6. Fault diagnosis

    Science.gov (United States)

    Abbott, Kathy

    1990-01-01

    The objective of the research in this area of fault management is to develop and implement a decision aiding concept for diagnosing faults, especially faults which are difficult for pilots to identify, and to develop methods for presenting the diagnosis information to the flight crew in a timely and comprehensible manner. The requirements for the diagnosis concept were identified by interviewing pilots, analyzing actual incident and accident cases, and examining psychology literature on how humans perform diagnosis. The diagnosis decision aiding concept developed based on those requirements takes abnormal sensor readings as input, as identified by a fault monitor. Based on these abnormal sensor readings, the diagnosis concept identifies the cause or source of the fault and all components affected by the fault. This concept was implemented for diagnosis of aircraft propulsion and hydraulic subsystems in a computer program called Draphys (Diagnostic Reasoning About Physical Systems). Draphys is unique in two important ways. First, it uses models of both functional and physical relationships in the subsystems. Using both models enables the diagnostic reasoning to identify the fault propagation as the faulted system continues to operate, and to diagnose physical damage. Draphys also reasons about behavior of the faulted system over time, to eliminate possibilities as more information becomes available, and to update the system status as more components are affected by the fault. The crew interface research is examining display issues associated with presenting diagnosis information to the flight crew. One study examined issues for presenting system status information. One lesson learned from that study was that pilots found fault situations to be more complex if they involved multiple subsystems. Another was pilots could identify the faulted systems more quickly if the system status was presented in pictorial or text format. Another study is currently under way to

  7. Fault-Related Sanctuaries

    Science.gov (United States)

    Piccardi, L.

    2001-12-01

    Beyond the study of historical surface faulting events, this work investigates the possibility, in specific cases, of identifying pre-historical events whose memory survives in myths and legends. The myths of many famous sacred places of the ancient world contain relevant telluric references: "sacred" earthquakes, openings to the Underworld and/or chthonic dragons. Given the strong correspondence with local geological evidence, these myths may be considered as describing natural phenomena. It has been possible in this way to shed light on the geologic origin of famous myths (Piccardi, 1999, 2000 and 2001). Interdisciplinary researches reveal that the origin of several ancient sanctuaries may be linked in particular to peculiar geological phenomena observed on local active faults (like ground shaking and coseismic surface ruptures, gas and flames emissions, strong underground rumours). In many of these sanctuaries the sacred area is laid directly above the active fault. In a few cases, faulting has affected also the archaeological relics, right through the main temple (e.g. Delphi, Cnidus, Hierapolis of Phrygia). As such, the arrangement of the cult site and content of relative myths suggest that specific points along the trace of active faults have been noticed in the past and worshiped as special `sacred' places, most likely interpreted as Hades' Doors. The mythological stratification of most of these sanctuaries dates back to prehistory, and points to a common derivation from the cult of the Mother Goddess (the Lady of the Doors), which was largely widespread since at least 25000 BC. The cult itself was later reconverted into various different divinities, while the `sacred doors' of the Great Goddess and/or the dragons (offspring of Mother Earth and generally regarded as Keepers of the Doors) persisted in more recent mythologies. Piccardi L., 1999: The "Footprints" of the Archangel: Evidence of Early-Medieval Surface Faulting at Monte Sant'Angelo (Gargano, Italy

  8. Slip rate variability over the Holocene period in the middle Aterno fault system (Italy), retrieved from in situ 36Cl cosmogenic nuclide dating of exhumed fault-plane.

    Science.gov (United States)

    Tesson, Jim; Benedetti, Lucilla; Pucci, Stefano; Villani, Fabio; Bourles, Didier; Keddadouche, Karim; Aumaitre, Georges

    2016-04-01

    Numerous numerical modeling studies have described and quantified non-stochastic spatio-temporal variations of earthquake occurrences within fault-networks, such as temporal clustered earthquakes or fault synchronization. However, very few long-enough paleoseismological and geological records are available to test those models against well-constrained dataset and thus account for such variability in the fault behavior. The prerequisites for improving our understanding of fault-rupture processes and thus our capacity to better assess seismic hazard are to acquire paleoseismological records that enable to derive both long-term slip-rate and short-term variability, on a large population of faults and/or within a fault system. These conditions met in Central Apennines, an extensional province where substantial paleoseismological dataset accurately described the Holocene seismic history of a dense network of normal faults. In this study we use 36Cl in situ cosmogenic nuclide to retrieve the seismic history of 3 faults belonging to the Middle Aterno fault system, from north to south: the Bazzano fault, the Roccapreturo fault and the Sulmona fault, a portion of which ruptured during the 2009 L'Aquila earthquake in Italy. We use a new modeling approach to determine the age and slip of past seismic events from the 36Cl concentration profiles. This model is based on an inverse approach and uses an optimization algorithm enabling all the parameter space (number of events, age and slip of events, pre-exposure) to be explored without a priori constraints (see Tesson et al. in session TS4.2/NH4.16/SM3.8). Using this new approach, we precisely determine the slip events occurrences over the Holocene period of those three faults. The results indicate that the three studied faults have ruptured between 4.5 and 5.5 ka, while the southernmost part of the system has also ruptured between at 1.5-3 ka (Sulmona fault and southern segment of Roccapreturo). Those results are in agreement

  9. Preliminary Report on the Seismological and Geotechnical Aspects of the April 6 2009 L'Aquila Earthquake in Central Italy (Version 2.0)

    OpenAIRE

    Stewart, J. P.; G. Di Capua; et al.

    2009-01-01

    The L’Aquila earthquake occurred on April 6 2009 at 03:32:39 local time. The earthquake was located in the central Italy region of Abruzzo. Much of the damage occurred in the capital city of L’Aquila, a city of approximate population 73000, although many small villages in the surrounding regions were significantly damaged including Paganica, Castelnuovo, and Onna. Collapsed and damaged structures in L’Aquila included both older masonry buildings and relatively modern reinforced...

  10. Source parameters of small and moderate earthquakes in the area of the 2009 L’Aquila earthquake sequence (central Italy)

    Science.gov (United States)

    D'Amico, Sebastiano; Orecchio, Barbara; Presti, Debora; Neri, Giancarlo; Wu, Wen-Nan; Sandu, Ilie; Zhu, Lupei; Herrmann, Robert B.

    The main goal of this study is to provide moment tensor solutions for small and moderate earthquakes of the 2009 L’Aquila seismic sequence (central Italy). The analysis was performed by using data coming from the permanent Italian seismic network run by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) and the “Cut And Paste” (CAP) method based on broadband waveform inversion. Focal mechanisms, source depths and moment magnitudes are determined through a grid search technique. By allowing time shifts between synthetics and observed data the CAP method reduces dependence of the solution on the assumed velocity model and on earthquake location. We computed seismic moment tensors for 312 earthquakes having local magnitude in the range between 2.7 and 5.9. The CAP method has made possible to considerably expand the database of focal mechanisms from waveform analysis in the lowest magnitude range (i.e. in the neighborhood of magnitude 3) without overlooking the reliability of results. The obtained focal mechanisms generally show NW-SE striking focal planes in agreement with mapped faults in the region. Comparisons with the already published solutions and with seismological and geological information available allowed us to proper interpret the moment tensor solutions in the frame of the seismic sequence evolution and also to furnish additional information about less energetic seismic phases. Focal data were inverted to obtain the seismogenic stress in the study area. Results are compatible with the major tectonic domain. We also obtained a relation between moment and local magnitude suitable for the area and for the available magnitude range.

  11. The earthquake lights (EQL of the 6 April 2009 Aquila earthquake, in Central Italy

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    C. Fidani

    2010-05-01

    Full Text Available A seven-month collection of testimonials about the 6 April 2009 earthquake in Aquila, Abruzzo region, Italy, was compiled into a catalogue of non-seismic phenomena. Luminous phenomena were often reported starting about nine months before the strong shock and continued until about five months after the shock. A summary and list of the characteristics of these sightings was made according to 20th century classifications and a comparison was made with the Galli outcomes. These sightings were distributed over a large area around the city of Aquila, with a major extension to the north, up to 50 km. Various earthquake lights were correlated with several landscape characteristics and the source and dynamic of the earthquake. Some preliminary considerations on the location of the sightings suggest a correlation between electrical discharges and asperities, while flames were mostly seen along the Aterno Valley.

  12. Decrease of VLF transmitter signal and Chorus-whistler waves before l'Aquila earthquake occurrence

    Directory of Open Access Journals (Sweden)

    M. Y. Boudjada

    2010-07-01

    Full Text Available We investigate the VLF emissions observed by the Instrument Champ Electrique (ICE experiment onboard the DEMETER micro-satellite. We analyze intensity level variation 10 days before and after the occurrence of l'Aquila earthquake (EQ. We found a clear decrease of the VLF received signal related to ionospheric whistler mode (mainly Chorus emission and to signal transmitted by the DFY VLF station in Germany, few days (more than one week before the earthquake. The VLF power spectral density decreases of more than two orders of magnitude until the EQ, and it recovers to normal levels just after the EQ occurrence. The geomagnetic activity is principally weak four days before EQ and increases again one day before l'Aquila seismic event. Our results are discussed in the frame of short- and long-terms earthquakes prediction focusing on the crucial role of the magnetic field of the Earth.

  13. Deformation pattern of the 6 and 7 April 2009, MW=6.3 and MW=5.6 earthquakes in L'Aquila (Central Italy revealed by ground and space based observations

    Directory of Open Access Journals (Sweden)

    E. L. Lekkas

    2010-01-01

    Full Text Available The deformation pattern of the 6 and 7 April 2009 MW=6.3 and MW=5.6 earthquakes in L'Aquila is revealed by DInSAR analysis and compared with earthquake environmental effects. The DInSAR predicted fault surface ruptures coincide with localities where surface ruptures have been observed in the field, confirming that the ruptures observed near Paganica village are indeed primary. These ruptures are almost one order of magnitude lower than the ruptures that have been produced by other major surrounding faults in the past. These faults have not been activated during the 2009 event, but have the capacity to generate significantly stronger events. DInSAR analysis shows that 66% (or 305 km2 of the area deformed has been subsided whereas the remaining 34% (or 155 km2 has been uplifted. A footwall uplift versus hangingwall subsidence ratio of about 1/3 is extracted from the mainshock. The maximum subsidence (25 cm was recorded about 4.5 km away from the primary surface ruptures and about 9 km away from the epicentre. In the immediate hangingwall, subsidence did not exceeded 15 cm, showing that the maximum subsidence is not recorded near the ruptured fault trace, but closer to the hangingwall centre. The deformation pattern is asymmetrical expanding significantly towards the southeast. A part of this asymmetry can be attributed to the contribution of the 7 April event in the deformation field.

  14. Surgical treatment of bumblefoot in a captive golden eagle (Aquila chrysaetos)

    OpenAIRE

    Saeed Nazifi; Moosa Javdani,; Seyedeh Leila Poorbaghi

    2012-01-01

    The golden eagle is one of the world's largest living birds. Footpad dermatitis, also known as plantar pododermatitis or bumblefoot, is a condition characterized by lesions due to contact with unhealthy "perching" conditions, such as plastic perches, sharp-cornered perches on the ventral footpad of birds. A young female golden eagle (Aquila chrysaetos) in Fars province of Iran was presented to veterinary clinics of Shiraz University with clinical signs of lameness. The bird was examined clini...

  15. L’Aquila, April 6, 2009: the emergency management, the promotion of cohesiveness and social health

    Directory of Open Access Journals (Sweden)

    Gian Piero Turchi

    2015-02-01

    Full Text Available This work is part of Progetto Vela, a project that aims at "the promotion of health" in communities struck by natural and humanitarian emergencies. It is an initiative organized by a research group from University of Padova (FISSPA Department - Philosophy, Sociology, Pedagogy and Psychology, born in October 2011 with the goal to investigate the outcome on the interactive structure of the community of L’Aquila, meaning how it is shaping its own social reality, after the earthquake of April 6, 2009. The opening words of the article are dedicated to a theoretical reflection on how elements such as "catastrophe", "health" and "emergency" are known, which led to assume the relevance of investigating them as they are configured by the members of the community, instead of considering them as static entities. In line with these assumptions, through specific survey protocols, we researched the discourse modes that shape the "health" of L’Aquila before the earthquake, during the hours of post-earthquake emergency, today and in the future. The protocols were administered to different roles (citizens, merchants, teachers, law enforcement officers, Civil Protection operators, doctors and psychologists, in order to collect the words of all the voices of the community. The findings showed that the people of L’Aquila still see their community as "living a catastrophe" and linked to the earthquake, which pervaded, and still pervades, the community’s biography (in past, present and future perspective with a high rate of potential social disintegration.

  16. Unfolding the procedure of characterizing recorded ultra low frequency, kHZ and MHz electromagnetic anomalies prior to the L'Aquila earthquake as pre-seismic ones - Part 2

    Directory of Open Access Journals (Sweden)

    K. Eftaxias

    2010-02-01

    Full Text Available Ultra low frequency-ULF (1 Hz or lower, kHz and MHz electromagnetic (EM anomalies were recorded prior to the L'Aquila catastrophic earthquake (EQ that occurred on 6 April 2009. The detected anomalies followed this temporal scheme. (i The MHz EM anomalies were detected on 26 March 2009 and 2 April 2009. The kHz EM anomalies were emerged on 4 April 2009. The ULF EM anomaly was appeared from 29 March 2009 up to 3 April 2009. The question effortlessly arises as to whether the observed anomalies before the L'Aquila EQ were seismogenic or not. The main goal of this work is to provide some insight into this issue. More precisely, the main aims of this contribution are threefold: How can we recognize an EM observation as pre-seismic one? We aim, through a multidisciplinary analysis to provide some elements of a definition. How can we link an individual EM anomaly with a distinctive stage of the EQ preparation process? The present analysis is consistent with the hypothesis that the kHz EM anomalies were associated with the fracture of asperities that were distributed along the L'Aquila fault sustaining the system, while the MHz EM anomalies could be triggered by fractures in the highly disordered system that surrounded the backbone of asperities of the activated fault. How can we identify precursory symptoms in an individual EM precursor that indicate that the occurrence of the EQ is unavoidable? We clearly state that the detection of a MHz EM precursor does not mean that the occurrence of EQ is unavoidable; the abrupt emergence of kHz EM emissions indicate the fracture of asperities. The observed ULF EM anomaly supports the hypothesis of a relationship between processes produced by increasing tectonic stresses in the Earth's crust and attendant EM interactions between the crust and ionosphere. We emphasize that we attempt to specify not only whether or not a single EM anomaly is pre-seismic in itself, but mainly whether a combination of emergent ULF

  17. Three-Dimensional Aquila Rift: Magnetized HI Arch Anchored by Molecular Complex

    Science.gov (United States)

    Sofue, Yoshiaki; Nakanishi, Hiroyuki

    2016-09-01

    Three dimensional structure of the Aquila Rift of magnetized neutral gas is investigated by analyzing HI and CO line data. The projected distance on the Galactic plane of the HI arch of the Rift is r⊥ ˜ 250 pc from the Sun. The HI arch emerges at l ˜ 30°, reaches to altitudes as high as ˜500 pc above the plane at l ˜ 350°, and returns to the disk at l ˜ 270°. The extent of arch at positive latitudes is ˜1 kpc and radius is ˜100 pc. The eastern root is associated with the giant molecular cloud complex, which is the main body of the optically defined Aquila Rift. The HI and molecular masses of the Rift are estimated to be M_HI˜ 1.4× 10^5M_{⊙ bullet } and M_H_2˜ 3× 10^5M_{⊙ bullet }. Gravitational energies to lift the gases to their heights are Egrav: HI ˜ 1.4 × 1051 and E_{grav: H_2}˜ 0.3× 10^{51} erg, respectively. Magnetic field is aligned along the HI arch of the Rift, and the strength is measured to be B ˜ 10 μG using Faraday rotation measures of extragalactic radio sources. The magnetic energy is estimated to be Emag ˜ 1.2 × 1051 erg. A possible mechanism of formation of the Aquila Rift is proposed in terms of interstellar magnetic inflation by a sinusoidal Parker instability of wavelength of ˜2.5 kpc and amplitude ˜500 pc.

  18. Broad-band strong motion simulations coupling k-square kinematic source models with empirical Green's functions: the 2009 L'Aquila earthquake

    Science.gov (United States)

    Del Gaudio, Sergio; Causse, Mathieu; Festa, Gaetano

    2015-10-01

    The use of simulated accelerograms may improve the evaluation of the seismic hazard when an accurate modelling of both source and propagation is performed. In this paper, we performed broad-band simulations of the 2009, M 6.3 L'Aquila earthquake, coupling a k-2 kinematic model for the seismic source with empirical Green's functions (EGFs) as propagators. We extracted 10 EGFs candidates from a database of aftershocks satisfying quality criteria based on signal-to-noise ratio, fault proximity, small magnitude, similar focal mechanism and stress drop. For comparison with real observations, we also derived a low-frequency kinematic model, based on inversion of ground displacement as integrated from strong motion data. Kinematic properties of the inverted model (rupture velocity, position of the rupture nucleation, low-frequency slip and roughness degree of slip heterogeneity) were used as constraints in the k-2 model, to test the use of a single specific EGF against the use of the whole set of EGFs. Comparison to real observations based on spectral and peak ground acceleration shows that the use of all available EGFs improves the fit of simulations to real data. Moreover the epistemic variability related to the selection of a specific EGF is significantly larger (two to three times) than recent observations of between event variability, that is the variability associated with the randomness of the rupture process. We finally performed `blind' simulations releasing all the information on source kinematics and only considering the fault geometry and the magnitude of the target event as known features. We computed peak ground acceleration, acceleration Fourier and response spectra. Simulations follow the same trend with distance as real observations. In most cases these latter fall within one sigma from predictions. Predictions with source parameters constrained at low frequency do not perform better than `blind' simulations, showing that extrapolation of the low

  19. L'Aquila 1962. "Alternative Attuali" e l'idea di "mostra-saggio"

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    Nicoletti, Luca Pietro

    2015-10-01

    Full Text Available Nel 1962 Enrico Crispolti inaugura, presso il Forte Cinquecentesco dell'Aquila, la prima edizione della rassegna "Alternative Attuali", proponendo un nuovo modello di mostra collettiva: non una semplice rassegna di artisti diversi, ma la proposta di un dialogo fra diverse posizioni (le "alternative" volte al superamento dell'Informale. Con il modello della "mostra-saggio", arricchita da un dibattito in catalogo, veniva per la prima volta applicata una idea espositiva che mettesse in prospettiva critica (e in proiezione storica la situazione presente.

  20. Heterogeneity and anomalous critical indices in the aftershocks distribution of L Aquila earthquake

    CERN Document Server

    Innocenti, D; Poccia, N; Ricci, A; Caputo, M; Bianconi, A

    2009-01-01

    The data analysis of aftershock events of L Aquila earthquake in Apennines following the main 6.3 Mw event of April 6, 2009 has been carried out by standard statistical geophysical tools. The results show the heterogeneity of seismic activity in five different geographical sub-regions indicated by anomalous critical indices of power law distributions: the exponents of the Omori law, the b values of Gutenberg-Richter magnitude-frequency distribution, and the distribution of waiting times. The heterogeneous distribution of dynamic stress and a different morphology in the five sub-regions has been found and two anomalous sub-regions have been identified.

  1. Caratteristiche geologiche e classificazione di sito delle stazioni accelerometriche della RAN ubicate a L'Aquila

    OpenAIRE

    2009-01-01

    L’evento sismico del 6 aprile 2009 è stato registrato da 57 stazioni accelerometriche delle RAN (Rete Accelerometrica Nazionale, gestita dal Dipartimento della Protezione Civile), alcune delle quali ubicate nella città di L’Aquila (stazione AQK) o nella porzione della Valle dell’Aterno a NW della città (AQA, AQF, AQG, AQM, AQP, AQV). Uno degli obiettivi del Progetto S4, finanziato nell’ambito della Convenzione 2007‐ 2009 tra l’Istituto Nazionale di Geofisica e il Dipartiment...

  2. [Mortality data in L'Aquila (Central Italy): few evidence, a lot of concerns].

    Science.gov (United States)

    Masedu, Francesco; Valenti, Marco

    2016-01-01

    The use of mortality data in L'Aquila public health post-earthquake experience considered as a population's health status indicator is completely missed. The deficit of regional and local epidemiological network in the period preceding the earthquake has clearly revealed a lack of specific activity, for example public reporting of morbidity and mortality in the seismic crater. This absence of a systematic use of current statistics needs a serious reflection concerning investments that regional public health needs to carry out on this topic.

  3. The Mitochondrial Genomes of Aquila fasciata and Buteo lagopus (Aves, Accipitriformes): Sequence, Structure and Phylogenetic Analyses

    OpenAIRE

    2015-01-01

    The family Accipitridae is one of the largest groups of non-passerine birds, including 68 genera and 243 species globally distributed. In the present study, we determined the complete mitochondrial sequences of two species of accipitrid, namely Aquila fasciata and Buteo lagopus, and conducted a comparative mitogenome analysis across the family. The mitogenome length of A. fasciata and B. lagopus are 18,513 and 18,559 bp with an A + T content of 54.2% and 55.0%, respectively. For both the two ...

  4. Optical and Near-Infrared spectroscopy of Nova V1494 Aquilae 1999 #2

    CERN Document Server

    Kamath, U S; Ashok, N M; Mayya, Y D; Sahu, D K

    2005-01-01

    Optical and near-infrared spectroscopic observations of the fast nova V1494 Aquilae 1999 #2 covering various phases -- early decline, transition and nebular -- during the first eighteen months of its post-outburst evolution are presented in this paper. During this period, the nova evolved in the P_fe P_fe^o C_o spectral sequence. The transition from an optically thick wind to a polar blob - equatorial ring geometry is seen in the evolution of the spectral line profiles. There is evidence of density and temperature stratification in the ejecta. Physical conditions in the ejecta have been estimated based on our observations.

  5. Heterotopic Ossification Secondary to Gunshot and Fragment Wounds in a Golden Eagle ( Aquila chrysaetos ).

    Science.gov (United States)

    Javdani, Moosa; Hashemnia, Mohammad; Nikousefat, Zahra

    2016-03-01

    Heterotopic ossification is the process of pathologic bone formation in soft tissue structures that usually do not form bone. An immature golden eagle ( Aquila chrysaetos ) was examined 2 months after a gunshot wound in the right wing. A solid oval mass with a gun pellet at its core was found attached to the ulna by a bony pedicle and was surgically excised. Heterotopic ossification secondary to gunshot and fragment wounds in the right ulna was diagnosed based on clinical, radiographic, and histopathologic findings. This report is the first to describe heterotopic ossification occurring around a gun pellet in a bird.

  6. Machine Fault Signature Analysis

    Directory of Open Access Journals (Sweden)

    Pratesh Jayaswal

    2008-01-01

    Full Text Available The objective of this paper is to present recent developments in the field of machine fault signature analysis with particular regard to vibration analysis. The different types of faults that can be identified from the vibration signature analysis are, for example, gear fault, rolling contact bearing fault, journal bearing fault, flexible coupling faults, and electrical machine fault. It is not the intention of the authors to attempt to provide a detailed coverage of all the faults while detailed consideration is given to the subject of the rolling element bearing fault signature analysis.

  7. Blog, social network e strategie narrative di resistenza nel post-terremoto dell’Aquila

    Directory of Open Access Journals (Sweden)

    Massimo Giuliani

    2013-06-01

    Full Text Available An earthquake, when it attacks a territory and its history, strikes the collective memory of a population. The reconstruction that followed the earthquake of L'Aquila contained elements that were equally problematic for the cohesion of the social and relational network, and therefore for mental health of stricken citizens and territories. Blogs, Facebook and online communication have been a possibility for the population (not only for the age group that usually makes use of digital technologies to share informations, chronicles, narrations about the postearthquake and to tell a story that was different from the sweetened one told by media. While trying a way to process loss and their own discomfort, many authors and bloggers became datum points for a community of readers thanks to their stories and chronicles. In addition, for the active citizenry the virtual setting of the Web became a substitute to the physical agora that had been wiped out by the earthquake and the dispersion of the community all over national territory. The experience of L'Aquila, also recreated through conversations with bloggers and the observation of Facebook status updates, shows interesting elements in order to understand the role of new media in everyday life and in an exceptional context such as collective trauma

  8. Renal disaster relief in Europe: the experience at L'Aquila, Italy, in April 2009.

    Science.gov (United States)

    Vanholder, Raymond; Stuard, Stefano; Bonomini, Mario; Sever, Mehmet Sukru

    2009-10-01

    On 6 April 2009, an earthquake struck the city of L'Aquila and the surrounding Abruzzo mountains. The disaster left 66,000 people homeless, while 1500 were wounded and 298 died. Although Europe as a whole is not so often affected by massive earthquakes, Italy is an exception with 12 earthquakes with an intensity >6.0 on the Richter scale during the last 100 years. This article offers preliminary information on the L'Aquila earthquake. For the time being, nine AKI patients who needed dialysis treatment are known. In all of them, kidney function recovered. This positive result can be attributed to the efficient and intensive rescue efforts coupled to the availability of disaster plans that had been developed in advance. This article stresses the importance of (i) advance planning of disaster rescue; (ii) the inclusion in these plans of approaches for kidney problems and their complications; (iii) the formulation of recommendations supporting (para-)medical professionals in their preventive, therapeutic and logistic approach to massive incidences of crush.

  9. Mortality in the l'aquila (central Italy) earthquake of 6 april 2009.

    Science.gov (United States)

    Alexander, David; Magni, Michele

    2013-01-07

    This paper presents the results of an analysis of data on mortality in the magnitude 6.3 earthquake that struck the central Italian city and province of L'Aquila during the night of 6 April 2009. The aim is to create a profile of the deaths in terms of age, gender, location, behaviour during the tremors, and other aspects. This could help predict the pattern of casualties and priorities for protection in future earthquakes. To establish a basis for analysis, the literature on seismic mortality is surveyed. The conclusions of previous studies are synthesised regarding patterns of mortality, entrapment, survival times, self-protective behaviour, gender and age. These factors are investigated for the data set covering the 308 fatalities in the L'Aquila earthquake, with help from interview data on behavioural factors obtained from 250 survivors. In this data set, there is a strong bias towards victimisation of young people, the elderly and women. Part of this can be explained by geographical factors regarding building performance: the rest of the explanation refers to the vulnerability of the elderly and the relationship between perception and action among female victims, who tend to be more fatalistic than men and thus did not abandon their homes between a major foreshock and the main shock of the earthquake, three hours later. In terms of casualties, earthquakes commonly discriminate against the elderly and women. Age and gender biases need further investigation and should be taken into account in seismic mitigation initiatives.

  10. Investigation of TEC and VLF space measurements associated to L'Aquila (Italy earthquakes

    Directory of Open Access Journals (Sweden)

    G. Stangl

    2011-04-01

    Full Text Available In this study, we report on Total Electron Content (TEC and Very Low Frequency (VLF space measurements derived from Global Positioning System (GPS and DEMETER satellites, respectively. These measurements are associated with the earthquake (EQ of a magnitude of 6.3, which occurred on 6 April 2009, in L'Aquila (Italy. Anomaly features are derived from the analysis of TEC and VLF observations recorded two weeks before and after the seismic event occurrence. A TEC map with an interpolated regional pixel resolution of 1° × 1° × 15 min in latitude, longitude and time was generated, allowing for the checking of a possible presence of disturbances over the L'Aquila region. This analysis is combined with the study of the time profile associated to the VLF flux density variations recorded by the Instrument Champ Electrique (ICE experiment on-board DEMETER satellite. We discuss, on the one hand, the combination efficiency of the electronic density and the VLF electromagnetic measurements and, on the other hand, the difficulty to distinguish between global effects and regional ones related to the earthquake.

  11. Science, Right and Communication of Risk in L'Aquila trial

    Science.gov (United States)

    Altamura, Marco; Miozzo, Davide; Boni, Giorgio; Amato, Davide; Ferraris, Luca; Siccardi, Franco

    2013-04-01

    CIMA Research Foundation has had access to all the information of the criminal trial held in l'Aquila intended against some of the members of the Commissione Nazionale Grandi Rischi (National Commission for Forecasting and Preventing Major Risks) and some directors of the Italian Civil Protection Department. These information constitute the base of a study that has examined: - the initiation of investigations by the families of the victims; - the public prosecutor's indictment; - the testimonies; - the liaison between experts in seismology social scientists and communication; - the statement of the defence; - the first instance decision of condemnation. The study reveals the paramount importance of communication of risk as element of prevention. Taken into particular account is the method of the Judicial Authority ex-post control on the evaluations and decisions of persons with a role of decision maker within the Civil Protection system. In the judgment just published by the Court of l'Aquila, the reassuring information from scientists and operators of Civil Protection appears to be considered as a negative value.

  12. Three-Dimensional Aquila Rift: Magnetized HI Arch Anchored by Molecular Complex

    CERN Document Server

    Sofue, Yoshiaki

    2016-01-01

    Three dimensional structure of the Aquila Rift of magnetized neutral gas is investigated by analyzing HI and CO line data. The projected distance on the Galactic plane of the HI arch of the Rift is ~250 pc from the Sun. The HI arch emerges at l~ 30 deg, reaches to altitudes as high as ~ 500 pc above the plane at l~ 350deg, and returns to the disk at l~270 deg. The extent of arch at positive latitudes is ~1 kpc and radius is ~100 pc. The eastern root is associated with the giant molecular cloud complex, which is the main body of the optically defined Aquila Rift. The HI and molecular masses of the Rift are estimated to be M_HI~1.4x10^5Msun and M_H2 ~3x10^5 Msun. Gravitational energies to lift the gases to their heights are E_grav: HI ~1.4x10^51 and E_grav: H_2 ~0.3x10^51 erg, respectively. Magnetic field is aligned along the HI arch of the Rift, and the strength is measured to be B~10 microG using Faraday rotation measures of extragalactic radio sources. The magnetic energy is estimated to be E_mag~1.2x10^51 e...

  13. Adaptive Response of Children and Adolescents with Autism to the 2009 Earthquake in L'Aquila, Italy

    Science.gov (United States)

    Valenti, Marco; Ciprietti, Tiziana; Di Egidio, Claudia; Gabrielli, Maura; Masedu, Francesco; Tomassini, Anna Rita; Sorge, Germana

    2012-01-01

    The literature offers no descriptions of the adaptive outcomes of people with autism spectrum disorder (ASD) after natural disasters. Aim of this study was to evaluate the adaptive behaviour of participants with ASD followed for 1 year after their exposure to the 2009 earthquake in L'Aquila (Italy) compared with an unexposed peer group with ASD,…

  14. Adaptive Response of Children and Adolescents with Autism to the 2009 Earthquake in L'Aquila, Italy

    Science.gov (United States)

    Valenti, Marco; Ciprietti, Tiziana; Di Egidio, Claudia; Gabrielli, Maura; Masedu, Francesco; Tomassini, Anna Rita; Sorge, Germana

    2012-01-01

    The literature offers no descriptions of the adaptive outcomes of people with autism spectrum disorder (ASD) after natural disasters. Aim of this study was to evaluate the adaptive behaviour of participants with ASD followed for 1 year after their exposure to the 2009 earthquake in L'Aquila (Italy) compared with an unexposed peer group with ASD,…

  15. Geosphere coupling and hydrothermal anomalies before the 2009 Mw 6.3 L'Aquila earthquake in Italy

    Directory of Open Access Journals (Sweden)

    L. Wu

    2016-08-01

    LCAC mode was proposed to interpret the possible mechanisms of the multiple quasi-synchronous anomalies preceding the L'Aquila earthquake. Results indicate that CO2-rich fluids in deep crust might have played a significant role in the local LCAC process.

  16. Quantifying structural uncertainty on fault networks using a marked point process within a Bayesian framework

    Science.gov (United States)

    Aydin, Orhun; Caers, Jef Karel

    2017-08-01

    Faults are one of the building-blocks for subsurface modeling studies. Incomplete observations of subsurface fault networks lead to uncertainty pertaining to location, geometry and existence of faults. In practice, gaps in incomplete fault network observations are filled based on tectonic knowledge and interpreter's intuition pertaining to fault relationships. Modeling fault network uncertainty with realistic models that represent tectonic knowledge is still a challenge. Although methods that address specific sources of fault network uncertainty and complexities of fault modeling exists, a unifying framework is still lacking. In this paper, we propose a rigorous approach to quantify fault network uncertainty. Fault pattern and intensity information are expressed by means of a marked point process, marked Strauss point process. Fault network information is constrained to fault surface observations (complete or partial) within a Bayesian framework. A structural prior model is defined to quantitatively express fault patterns, geometries and relationships within the Bayesian framework. Structural relationships between faults, in particular fault abutting relations, are represented with a level-set based approach. A Markov Chain Monte Carlo sampler is used to sample posterior fault network realizations that reflect tectonic knowledge and honor fault observations. We apply the methodology to a field study from Nankai Trough & Kumano Basin. The target for uncertainty quantification is a deep site with attenuated seismic data with only partially visible faults and many faults missing from the survey or interpretation. A structural prior model is built from shallow analog sites that are believed to have undergone similar tectonics compared to the site of study. Fault network uncertainty for the field is quantified with fault network realizations that are conditioned to structural rules, tectonic information and partially observed fault surfaces. We show the proposed

  17. Extended Ensemble Monte Carlo

    OpenAIRE

    Iba, Yukito

    2000-01-01

    ``Extended Ensemble Monte Carlo''is a generic term that indicates a set of algorithms which are now popular in a variety of fields in physics and statistical information processing. Exchange Monte Carlo (Metropolis-Coupled Chain, Parallel Tempering), Simulated Tempering (Expanded Ensemble Monte Carlo), and Multicanonical Monte Carlo (Adaptive Umbrella Sampling) are typical members of this family. Here we give a cross-disciplinary survey of these algorithms with special emphasis on the great f...

  18. Seismic slip history of the Aterno-Sulmona fault system in central Apennines (Italy) using in situ produced 36Cl cosmic ray exposure dating.

    Science.gov (United States)

    Jim, T.; Benedetti, L. C.; Bruno, P.; Visini, F.; Aumaitre, G.; Bourles, D. L.

    2014-12-01

    Acquiring long records of past earthquakes on a large population of faults is a key step to understand how strain release along those fault systems varies spatially and temporally.In central Italy, NE-SW extension (~4 mm/yr) is accommodated on a wide normal fault system (50 x 100km). Benedetti et al. (2013) found that 7 of these faults, belonging to the Fucino fault system, have their seismic activity synchronized during short (less than 1 ka) paroxysmal phases of activity. 36Cl measurements and rare earth elements (REE) concentrations were used to reconstruct the seismic slip history of four major faults belonging to an adjacent 30-km-long fault system, the Aterno-Sulmona fault system, at the southeastward tip of the Paganica fault that ruptured during the 2009 L'Aquila earthquake.The preliminary results suggest that 3-7 seismic events have occurred on each fault over the last 11 ka (from NE to SW the Roccapreturo, the Castel di Ieri, the Roccacasale and the Pizzalto faults), with 50 cm to 2 m of associated slip per event. These events appear clustered within intense period of seismic activity lasting less than 1ka (2 to 4 seismic events) separated by 2 to 3 ka periods with no seismic events. The most recent recorded paroxysmal activity occurred about 2.5 ka ago with all four studied faults rupturing in more than 15 earthquakes over a period lasting less than 1ka. These results thus suggest that, as already observed on the Fucino fault system, the seismic activity of the Aterno-Sulmona fault system is also synchronized during short periods of paroxysmal seismic activity.When clustering periods are compared, the seismic activity of the Fucino and the Aterno-Sulmona fault system, are, however, apparently unsynchronized since the most recent clustering period for the Aterno-Sulmona system corresponds to a quiescent period for the Fucino fault system.

  19. Architectural and microstructural characterization of a seismogenic normal fault in dolostones (Central Apennines, Italy)

    Science.gov (United States)

    Demurtas, Matteo; Fondriest, Michele; Clemenzi, Luca; Balsamo, Fabrizio; Storti, Fabrizio; Di Toro, Giulio

    2015-04-01

    Fault zones cutting carbonate sequences represent significant seismogenic sources worldwide (e.g. L'Aquila 2009, MW 6.1). Though seismological and geophysical techniques (double differences method, trapped waves, etc.) allow us to investigate down to the decametric scale the structure of active fault zones, further geological field surveys and microstructural studies of exhumed seismogenic fault zones are required to support interpretation of geophysical data, quantify the geometry of fault zones and identify the fault processes active during the seismic cycle. Here we describe the architecture (i.e. fault geometry and fault rock distribution) of the well-exposed footwall-block of the Campo Imperatore Fault Zone (CIFZ) by means of remote sensed analyses, field surveys, mineralogical (XRD, micro-Raman spectroscopy) and microstructural (FE-SEM, optical microscope cathodoluminescence) investigations. The CIFZ dips 58° towards N210 and its strike mimics that of the arcuate Gran Sasso Thrust Belt (Central Apennines). The CIFZ was exhumed from 2-3 km depth and accommodated a normal throw of ~2 km starting from the Early-Pleistocene. In the studied area, the CIFZ puts in contact the Holocene deposits at the hangingwall with dolomitized Jurassic carbonate platform successions (Calcare Massiccio) at the footwall. From remote sensed analyses, structural lineaments both inside and outside the CIFZ have a typical NW-SE Apenninic strike, which is parallel to the local trend of the Gran Sasso Thrust. Based on the density of the fracture/fault network and the type of fault zone rocks, we distinguished four main structural domains within the ~300 m thick CIFZ footwall-block, which include (i) a well-cemented (white in color) cataclastic zone (up to ~40 m thick) at the contact with the Holocene deposits, (ii) a well-cemented (brown to grey in color) breccia zone (up to ~15 m thick), (iii) an high strain damage zone (fracture spacing 10 cm). Other than by the main boundary normal

  20. [The new territorial configuration of L'Aquila (Central Italy) after the 2009 earthquake and places and behaviours changes of everyday life].

    Science.gov (United States)

    Castellani, Serena; Palma, Francesca; Calandra, Lina Maria

    2016-01-01

    Since 2010, the Cartolab Laboratory research team (Department of Human Studies, University of L'Aquila) has been investigating the social geography in the post-earthquake period through the analysis of the territorial changes and new sociospatial configurations occurred in the everyday life of the L'Aquila inhabitants. Accordingly, this paper aims to describe the principal results of researches concentrating on the use of leisure time and leisure places in the post-disaster period in L'Aquila. The paper uses an action-research/participating- participatory (RAPP) methodology. The paper presents the monitored changes occurred in leisure time and places, and compares them with the conditions before the earthquake. Primary data have been retrieved by surveys and interviews. Results indicate that acceleration of fragmentation and dispersion of inhabitants are the main characteristics of the new sociospatial configuration in the post-disaster period in L'Aquila.

  1. Un San Sebastiano di Silvestro dell’Aquila e un San Vito di Saturnino Gatti / A St. Sebastian by Silvestro dell’Aquila and a St. Vitus by Saturnino Gatti

    Directory of Open Access Journals (Sweden)

    Lorenzo Principi

    2015-06-01

    Full Text Available L’articolo si focalizza sull’attribuzione di un’inedita statua a Silvestro di Giacomo da Sulmona, meglio noto come Silvestro dell’Aquila (documentato dal 1471-1504 e un’altra a Saturnino Gatti (1463 circa-1518, protagonisti della scultura del Rinascimento in Abruzzo. La prima proposta riguarda un San Sebastiano ligneo, grande poco meno del vero, conservato nella chiesa di Santa Maria ad Nives di Rocca di Mezzo, principale centro dell’Altipiano delle Rocche e paese natale del celebre cardinale Amico Agnifili, committente di Silvestro di Giacomo. La seconda acquisizione concerne una scultura lignea grande al naturale raffigurante San Vito, rintracciata nell’omonima chiesa di Colle San Vito, nel comune di Tornimparte, situata a pochi passi dagli affreschi eseguiti da Saturnino Gatti tra il 1490 e il 1494 in San Panfilo a Villagrande. Grazie ad un’analisi dei diversi contesti in cui si generarono le sculture e soprattutto attraverso stringenti confronti con opere note del catalogo dei due artisti si può riferire la prima statua alla tarda produzione di Silvestro dell’Aquila e la seconda al periodo di maturità di Saturnino Gatti.   The article focuses on the attribution of two unpublished wooden statues respectively realized by two masters of Renaissance sculpture in Abruzzo: Silvestro di Giacomo, known as Silvestro dell’Aquila (whose activity is documented at L’Aquila from 1471 to 1504; and Saturnino Gatti. The scultpure attributed to Silvestro dell’Aquila portrays Saint Sebastian, and is of almost life-size dimensions. It was spotted out inside the church of Santa Maria ad Nives at Rocca di Mezzo, the most renowned village on the upland of «Le Rocche», in the nearbies of L’Aquila; it was the birthplace of Cardinal Amico Agnifili, who happened to be Silvestro’s patron. The second statue, by Saturnino Gatti, represents Saint Vitus and is hold in the homonymous church at Colle San Vito in the municipal district of

  2. The asynchronous polar V1432 Aquilae and its path back to synchronism

    CERN Document Server

    Boyd, David; Allen, William; Bolt, Greg; Bonnardeau, Michel; Tut,; Campbell, Jeannie; Cejudo, David; Cook, Michael; de Miguel, Enrique; Ding, Claire; Dvorak, Shawn; Foote, Jerrold; Fried, Robert; Hambsch, Franz-Josef; Kemp, Jonathan; Krajci, Thomas; Monard, Berto; Ogmen, Yenal; Rea, Robert; Roberts, George; Skillman, David; Starkey, Donn; Ulowetz, Joseph; Uthas, Helena; Walker, Stan

    2014-01-01

    V1432 Aquilae is the only known eclipsing asynchronous polar. In this respect it is unique and therefore merits our attention. We report the results of a 15-year campaign by the globally distributed Center for Backyard Astrophysics to observe V1432 Aql and investigate its return to synchronism. Originally knocked out of synchrony by a nova explosion before observing records began, the magnetic white dwarf in V1432 Aql is currently rotating slower than the orbital period but is gradually catching up. The fortuitously high inclination of the binary orbit affords us the bonus of eclipses providing a regular clock against which these temporal changes can be assessed. At the present rate, synchronism should be achieved around 2100. The continually changing trajectory of the accretion stream as it follows the magnetic field lines of the rotating white dwarf produces a complex pattern of light emission which we have measured and documented, providing comprehensive observational evidence against which physical models...

  3. Not an open cluster after all: the NGC 6863 asterism in Aquila

    CERN Document Server

    Bidin, Christian Moni; Marcos, Carlos de la Fuente; Carraro, Giovanni

    2009-01-01

    Shortly after birth, open clusters start dissolving; gradually losing stars into the surrounding star field. The time scale for complete disintegration depends both on their initial membership and location within the Galaxy. Open clusters undergoing the terminal phase of cluster disruption or open cluster remnants (OCRs) are notoriously difficult to identify. From an observational point, a combination of low number statistics and minimal contrast against the general stellar field conspire to turn them into very challenging objects. To make the situation even worst, random samples of field stars often display features that may induce to classify them erroneously as extremely evolved open clusters. In this paper, we provide a detailed study of the stellar content and kinematics of NGC 6863, a compact group of a few stars located in Aquila and described by the POSS as a non existent cluster. Nonetheless, this object has been recently classified as OCR. The aim of the present work is to either confirm or disprove...

  4. The Gould's Belt Distances Survey (GOBELINS) III. The distance to the Serpens/Aquila Molecular Complex

    CERN Document Server

    Ortiz-León, Gisela N; Kounkel, Marina A; Loinard, Laurent; Mioduszewski, Amy J; Rodríguez, Luis F; Torres, Rosa M; Pech, Gerardo; Rivera, Juana L; Hartmann, Lee; Boden, Andrew F; Evans, Neal J; Briceño, Cesar; Tobin, John J; Galli, Phillip A B

    2016-01-01

    We report on new distances and proper motions to seven stars across the Serpens/Aquila complex. The observations were obtained as part of the Gould's Belt Distances Survey (GOBELINS) project between September 2013 and April 2016 with the Very Long Baseline Array (VLBA). One of our targets is the proto-Herbig AeBe object EC 95, which is a binary system embedded in the Serpens Core. For this system, we combined the GOBELINS observations with previous VLBA data to cover a total period of ~8 years, and derive the orbital elements and an updated source distance. The individual distances to sources in the complex are fully consistent with each other, and the mean value corresponds to a distance of $436.0\\pm9.2$~pc for the Serpens/W40 complex. Given this new evidence, we argue that Serpens Main, W40 and Serpens South are physically associated and form a single cloud structure.

  5. A self consistent chemically stratified atmosphere model for the roAp star 10 Aquilae

    CERN Document Server

    Nesvacil, Nicole; Ryabchikova, Tanya A; Kochukhov, Oleg; Akberov, Artur; Weiss, Werner W

    2012-01-01

    Context: Chemically peculiar A type (Ap) stars are a subgroup of the CP2 stars which exhibit anomalous overabundances of numerous elements, e.g. Fe, Cr, Sr and rare earth elements. The pulsating subgroup of the Ap stars, the roAp stars, present ideal laboratories to observe and model pulsational signatures as well as the interplay of the pulsations with strong magnetic fields and vertical abundance gradients. Aims: Based on high resolution spectroscopic observations and observed stellar energy distributions we construct a self consistent model atmosphere, that accounts for modulations of the temperature-pressure structure caused by vertical abundance gradients, for the roAp star 10 Aquilae (HD 176232). We demonstrate that such an analysis can be used to determine precisely the fundamental atmospheric parameters required for pulsation modelling. Methods: Average abundances were derived for 56 species. For Mg, Si, Ca, Cr, Fe, Co, Sr, Pr, and Nd vertical stratification profiles were empirically derived using the...

  6. Evidence of underground electric current generation during the 2009 L'Aquila earthquake: Real or instrumental?

    Science.gov (United States)

    Masci, F.; Thomas, J. N.

    2016-06-01

    We investigate magnetic effects in correspondence of the Mw6.1 L'Aquila earthquake. Magnetic and seismic records are analyzed. Rapid and distinct changes and an offset can be seen in magnetic field components after the main shock. We show that these effects result from electromagnetic induction due to the movement of the sensors through the Earth's magnetic field and from a permanent displacement of the sensors from their original position caused by the passing seismic waves. A transient signal in total field data from an overhauser magnetometer apparently occurs in correspondence with the earthquake. Our analysis shows that the transient was not observed by other sensors that were operating in close proximity to the overhauser. Thus, the transient signal in the total magnetic field data, and the offset in the magnetic field components, cannot be associated with a hypothetical underground electric current generated by the earthquake, as suggested by Nenovski (2015).

  7. Common Raven (Corvus corax) kleptoparasitism at a Golden Eagle (Aquila chyrsaetos) nest in southern Nevada

    Science.gov (United States)

    Simes, Matthew; Johnson, Diego R.; Streit, Justin; Longshore, Kathleen; Nussear, Kenneth E.; Esque, Todd C.

    2017-01-01

    The Common Raven (Corvus corax) is a ubiquitous species in the Mojave Desert of southern Nevada and California. From 5 to 24 May 2014, using remote trail cameras, we observed ravens repeatedly kleptoparasitizing food resources from the nest of a pair of Golden Eagles (Aquila chyrsaetos) in the Spring Mountains of southern Nevada. The ravens fed on nine (30%) of the 30 prey items delivered to the nest during the chick rearing period. Kleptoparasitic behavior by the ravens decreased as the eagle nestling matured to seven weeks of age, suggesting a narrow temporal window in which ravens can successfully engage in kleptoparasitic behavior at eagle nests. The observation of kleptoparasitism by Common Ravens at the nest suggests potential risks to young Golden Eagles from Common Ravens.

  8. Short-term earthquake probabilities during the L'Aquila earthquake sequence in central Italy, 2009

    Science.gov (United States)

    Falcone, G.; Murru, M.; Zhuang, J.; Console, R.

    2014-12-01

    We compare the forecasting performance of several statistical models, which are used to describe the occurrence process of earthquakes, in forecasting the short-term earthquake probabilities during the occurrence of the L'Aquila earthquake sequence in central Italy, 2009. These models include the Proximity to Past Earthquakes (PPE) model and different versions of the Epidemic Type Aftershock Sequence (ETAS) model. We used the information gains corresponding to the Poisson and binomial scores to evaluate the performance of these models. It is shown that all ETAS models work better than the PPE model. However, when comparing the different types of the ETAS models, the one with the same fixed exponent coefficient α = 2.3 for both the productivity function and the scaling factor in the spatial response function, performs better in forecasting the active aftershock sequence than the other models with different exponent coefficients when the Poisson score is adopted. These latter models perform only better when a lower magnitude threshold of 2.0 and the binomial score are used. The reason is likely due to the fact that the catalog does not contain an event of magnitude similar to the L'Aquila main shock (Mw 6.3) in the training period (April 16, 2005 to March 15, 2009). In this case the a-value is under-estimated and thus also the forecasted seismicity is underestimated when the productivity function is extrapolated to high magnitudes. These results suggest that the training catalog used for estimating the model parameters should include earthquakes of similar magnitudes as the main shock when forecasting seismicity is during an aftershock sequences.

  9. Causes of hospitalisation before and after the 2009 L'Aquila earthquake.

    Science.gov (United States)

    Petrazzi, L; Striuli, R; Polidoro, L; Petrarca, M; Scipioni, R; Struglia, M; Giorgini, P; Necozione, S; Festuccia, V; Ferri, C

    2013-09-01

    On 6 April 2009, an earthquake struck L'Aquila. The San Salvatore Hospital was evacuated, and a field hospital was built. The study aimed to assess the epidemiologic impact of the earthquake through the analysis of patient population admitted to the field hospital during a 2-month period following the disaster. We retrospectively evaluated causes of hospitalisation and demographic data of patients admitted to (i) the Division of Internal Medicine and (ii) the Division of Emergency Medicine of the field hospital from 6 April, 2009 to 29 May, 2009. All data were compared with the admissions made at the same divisions of the San Salvatore Hospital during the same period of previous year. (i) Patient group (n = 102) and comparison group (n = 108). Mean patient age was higher, patients living in L'Aquila were more numerous, while mean length of stay was lower after than before the earthquake. Infectious diseases increased, while 'other' diseases decreased after the disaster both in admission and in discharge diagnoses. Gastroenterological diseases decreased with the earthquake but only in admission diagnoses. (ii) Patient group (n = 5255) and comparison group (n = 6564). Triage codes changed with the earthquake. Cardiovascular, psychiatric, gynaecological, infectious and chronic diseases increased, while pneumologic, gastroenterological, traumatic and 'other' diseases decreased after the quake. The number of hospitalised patients decreased with the tremor, while those discharged transferred to other hospitals and those who rejected hospitalisation increased. A natural disaster completely changes causes of hospitalisation in the Divisions of Internal and Emergency Medicine. These findings can be useful for the design of specific intervention programmes and for softening the detrimental effects of quakes.

  10. Paleomagnetism of a 150 m Sediment Core from the Co-Seismic Subsidence Depocenter of the 2009 Mw=6.1 L'Aquila Earthquake (Italy)

    Science.gov (United States)

    Macri', P.; Porreca, M.; Sagnotti, L.; Smedile, A.; Speranza, F.

    2014-12-01

    The 150 m deep borehole LAQUI-CORE was drilled in the co-seismic subsidence depocenter, shown by INSAR images in the middle Aterno continental basin, after the 2009 Mw=6.1 earthquake that struck the historical city of L'Aquila (Italy). The drill site was located where geological, seismological and geophysical surveys indicated a continuous record with a maximum thickness of fine-grained sediments. The aim was to investigate stratigraphic and geometrical architecture of the middle Aterno basin, in order to define its relationship with the local active fault system. The core consists of continental Holocene and Pleistocene sediments subdivided into two main sequences separated by an erosional discontinuity. The upper sequence consists of 41 m thick fluvial-alluvial deposits of silt and sand interbedded with metric intervals of rounded gravel. The lower sequence consists of palustrine sediments of clays and sands interrupted in the middle by a 30 m thick coarse gravel deposit. Biostratigraphic and radiometric measurements on the core are still in progress, while high-resolution paleomagnetic and rock magnetic measurements were performed on u-channel samples. Natural remanent magnetization (NRM), anhysteretic remanent magnetization (ARM), magnetic susceptibility (k) were measured at 1-cm spacing using a 2G Cryogenic magnetometer. The sediments carry a well-defined characteristic remanent magnetization (ChRM), isolated between 15 and 40 mT AF steps. The ChRM is of normal polarity down to ca. 83 m depth, with paleomagnetic inclination values oscillating around 57°. The main magnetic carrier in this interval is magnetite, below ca. 115 m depth the data show frequent apparent polarity changes due to the additional widespread occurrence of greigite. This interval has to be anyway older than the Brunhes-Matuyama transition. Relative paleointensity (RPI) curves were obtained by normalising the NRM20mT with k and ARM20mT and may be useful to improve the dating of the core.

  11. Monte Carlo fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    Brown, F.B.; Sutton, T.M.

    1996-02-01

    This report is composed of the lecture notes from the first half of a 32-hour graduate-level course on Monte Carlo methods offered at KAPL. These notes, prepared by two of the principle developers of KAPL`s RACER Monte Carlo code, cover the fundamental theory, concepts, and practices for Monte Carlo analysis. In particular, a thorough grounding in the basic fundamentals of Monte Carlo methods is presented, including random number generation, random sampling, the Monte Carlo approach to solving transport problems, computational geometry, collision physics, tallies, and eigenvalue calculations. Furthermore, modern computational algorithms for vector and parallel approaches to Monte Carlo calculations are covered in detail, including fundamental parallel and vector concepts, the event-based algorithm, master/slave schemes, parallel scaling laws, and portability issues.

  12. Monte Carlo methods

    OpenAIRE

    Bardenet, R.

    2012-01-01

    ISBN:978-2-7598-1032-1; International audience; Bayesian inference often requires integrating some function with respect to a posterior distribution. Monte Carlo methods are sampling algorithms that allow to compute these integrals numerically when they are not analytically tractable. We review here the basic principles and the most common Monte Carlo algorithms, among which rejection sampling, importance sampling and Monte Carlo Markov chain (MCMC) methods. We give intuition on the theoretic...

  13. Exploring Monte Carlo methods

    CERN Document Server

    Dunn, William L

    2012-01-01

    Exploring Monte Carlo Methods is a basic text that describes the numerical methods that have come to be known as "Monte Carlo." The book treats the subject generically through the first eight chapters and, thus, should be of use to anyone who wants to learn to use Monte Carlo. The next two chapters focus on applications in nuclear engineering, which are illustrative of uses in other fields. Five appendices are included, which provide useful information on probability distributions, general-purpose Monte Carlo codes for radiation transport, and other matters. The famous "Buffon's needle proble

  14. Fault Tolerant Feedback Control

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2001-01-01

    An architecture for fault tolerant feedback controllers based on the Youla parameterization is suggested. It is shown that the Youla parameterization will give a residual vector directly in connection with the fault diagnosis part of the fault tolerant feedback controller. It turns out...... that there is a separation be-tween the feedback controller and the fault tolerant part. The closed loop feedback properties are handled by the nominal feedback controller and the fault tolerant part is handled by the design of the Youla parameter. The design of the fault tolerant part will not affect the design...... of the nominal feedback con-troller....

  15. AQUILA Remotely Piloted Vehicle System Technology Demonstrator (RPV-STD) Program. Volume I. System Description and Capabilities

    Science.gov (United States)

    1979-04-01

    is selectively distributed by an RPV ground control box specially designed by LMSC for the Aquila system. Both units and the RPV umbilical power cord ...View. . 0 . ... 0 . . .. . .... . 282 137 Schematic Drawing of Dryer .................... o 284 138 Remote Umbilical Removal ........ ....... ... .. 268...support on the assembly stand. The vehicle is clamped to the stand at the wing stub trailing edge and by the lnching skeg to prevent slippage and

  16. Light for Earthquake Prediction:Shocks before the L'Aquila Earthquake of April 6,2009

    Institute of Scientific and Technical Information of China (English)

    Li Li; Chen Yong

    2010-01-01

    The temporal-spatial distribution of mid-small earthquakes in Italy and its surroundings from January 1 to April 5,2009 shows that there were significant foreshocks before the moderate L'Aquila earthquake of April 6,2009.The enhancement of frequency and intensity of small earthquakes and their concentrating tendency to the future main shock have provided a comprehensive case for digging methods of earthquake forecasting with foreshocks.

  17. L’Aquila, 6 aprile 2009: la gestione dell’emergenza, la promozione della coesione e della salute sociale

    Directory of Open Access Journals (Sweden)

    G.P. Turchi

    2015-03-01

    Full Text Available This work is part of Progetto Vela, a project that aims at "the promotion of health" in communities struck by natural and humanitarian emergencies. It is an initiative organized by a research group from University of Padova (FISSPA Department - Philosophy, Sociology, Pedagogy and Psychology, born in October 2011 with the goal to investigate the outcome on the interactive structure of the community of L’Aquila, meaning how it is shaping its own social reality, after the earthquake of April 6, 2009. The opening words of the article are dedicated to a theoretical reflection on how elements such as "catastrophe", "health" and "emergency" are known, which led to assume the relevance of investigating them as they are configured by the members of the community, instead of considering them as static entities. In line with these assumptions, through specific survey protocols, we researched the discourse modes that shape the "health" of L’Aquila before the earthquake, during the hours of post-earthquake emergency, today and in the future. The protocols were administered to different roles (citizens, merchants, teachers, law enforcement officers, Civil Protection operators, doctors and psychologists, in order to collect the words of all the voices of the community. The findings showed that the people of L’Aquila still see their community as "living a catastrophe" and linked to the earthquake, which pervaded, and still pervades, the community’s biography (in past, present and future perspective with a high rate of potential social disintegration.

  18. Magnetic transfer function entropy and the 2009 Mw = 6.3 L'Aquila earthquake (Central Italy

    Directory of Open Access Journals (Sweden)

    L. X. Wu

    2012-07-01

    Full Text Available With the aim of obtaining a deeper knowledge of the physical phenomena associated with the 2009 L'Aquila (Central Italy seismic sequence, culminating with a Mw = 6.3 earthquake on 6 April 2009, and possibly of identifying some kind of earthquake-related magnetic or geoelectric anomaly, we analyse the geomagnetic field components measured at the magnetic observatory of L'Aquila and their variations in time. In particular, trends of magnetic transfer functions in the years 2006–2010 are inspected. They are calculated from the horizontal to vertical magnetic component ratio in the frequency domain, and are very sensitive to deep and lateral geoelectric characteristics of the measurement site. Entropy analysis, carried out from the transfer functions with the so called transfer function entropy, points out clear temporal burst regimes of a few distinct harmonics preceding the main shock of the seismic sequence. A possible explanation is that they could be related to deep fluid migrations and/or to variations in the micro-/meso-fracturing that affected significantly the conductivity (ordered/disordered distribution in a large lithospheric volume under the seismogenic layer below L'Aquila area. This interpretation is also supported by the analysis of hypocentres depths before the main shock occurrence.

  19. Geosphere coupling and hydrothermal anomalies before the 2009 Mw 6.3 L'Aquila earthquake in Italy

    Science.gov (United States)

    Wu, Lixin; Zheng, Shuo; De Santis, Angelo; Qin, Kai; Di Mauro, Rosa; Liu, Shanjun; Rainone, Mario Luigi

    2016-08-01

    The earthquake anomalies associated with the 6 April 2009 Mw 6.3 L'Aquila earthquake have been widely reported. Nevertheless, the reported anomalies have not been so far synergically analyzed to interpret or prove the potential lithosphere-coversphere-atmosphere coupling (LCAC) process. Previous studies on b value (a seismicity parameter from Gutenberg-Richter law) are also insufficient. In this work, the spatiotemporal evolution of several hydrothermal parameters related to the coversphere and atmosphere, including soil moisture, soil temperature, near-surface air temperature, and precipitable water, was comprehensively investigated. Air temperature and atmospheric aerosol were also statistically analyzed in time series with ground observations. An abnormal enhancement of aerosol occurred on 30 March 2009 and thus proved quasi-synchronous anomalies among the hydrothermal parameters from 29 to 31 March in particular places geo-related to tectonic thrusts and local topography. The three-dimensional (3-D) visualization analysis of b value revealed that regional stress accumulated to a high level, particularly in the L'Aquila basin and around regional large thrusts. Finally, the coupling effects of geospheres were discussed, and a conceptual LCAC mode was proposed to interpret the possible mechanisms of the multiple quasi-synchronous anomalies preceding the L'Aquila earthquake. Results indicate that CO2-rich fluids in deep crust might have played a significant role in the local LCAC process.

  20. Well-being and perceived quality of life in elderly people displaced after the earthquake in L'Aquila, Italy.

    Science.gov (United States)

    Giuliani, Anna Rita; Mattei, Antonella; Santilli, Flavio; Clori, Giovanna; Scatigna, Maria; Fabiani, Leila

    2014-06-01

    On 6 April 2009, the city of L'Aquila was hit by a violent earthquake that destroyed almost all of its medieval centre, and the surviving inhabitants were evacuated and relocated in temporary quarters or undamaged homes. The aim of this study was to investigate the perceived quality of life of the elderly population 3 years after the earthquake in relation to the social and logistic issues of new housing. The study was carried out between October 2011 and March 2012, and involved 571 subjects aged over 65 years living in the municipality of L'Aquila. The interviews took place in the surgeries of general practitioners and the city's Department of Prevention and Vaccination in the anti-influenza immunisation period. The instrument used was a 36-item questionnaire with closed, multiple choice answers divided into the following sections: demographics, everyday activities, health and perceived health, and the quality of life in the city. The results show that, 3 years after the earthquake, the elderly population living in the new towns and temporary housing of L'Aquila have a worse perception of their quality of life than the others. They feel a certain social isolation and wish to live elsewhere. Governments faced with the problems arising from a natural calamity should take into account all of the elements making up a good quality of life and, before making choices whose impact cannot be changed, consider both their immediate and long-term social consequences.

  1. Incertitude in disaster sciences and scientists' responsibilities: A case study of the L'Aquila earthquake trial

    Science.gov (United States)

    Koketsu, Kazuki; Oki, Satoko

    2015-04-01

    What disaster sciences are expected by the society is to prevent or mitigate future natural disasters, and therefore it is necessary to foresee natural disasters. However, various constraints often make the foreseeing difficult so that there is a high incertitude in the social contribution of disaster sciences. If scientists overstep this limitation, they will be held even criminally responsible. The L'Aquila trial in Italy is such a recent example and so we have performed data collections, hearing investigations, analyses of the reasons for the initial court's judgment, etc., to explore the incertitude of disaster sciences and scientists' responsibilities. As a result, we concluded that the casualties during the L'Aquila earthquake were mainly due to a careless "safety declaration" by the vice-director of the Civil Protection Agency, where the incertitude of disaster sciences had never been considered. In addition, news media which reported only this "safety declaration" were also seriously responsible for the casualties. The accused other than the vice-director were only morally responsible, because their meeting remarks included poor risk communication in disaster sciences but those were not reported to the citizens in advance to the L'Aquila earthquake. In the presentation, we will also discuss the similarities and differences between our conclusions above and the reasons for the appeals court's judgement, which will be published in February.

  2. Fault detection and isolation in systems with parametric faults

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, Hans Henrik

    1999-01-01

    The problem of fault detection and isolation of parametric faults is considered in this paper. A fault detection problem based on parametric faults are associated with internal parameter variations in the dynamical system. A fault detection and isolation method for parametric faults is formulated...

  3. Iowa Bedrock Faults

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This fault coverage locates and identifies all currently known/interpreted fault zones in Iowa, that demonstrate offset of geologic units in exposure or subsurface...

  4. null Faults, null Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Through the study of faults and their effects, much can be learned about the size and recurrence intervals of earthquakes. Faults also teach us about crustal...

  5. Performance based fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2002-01-01

    Different aspects of fault detection and fault isolation in closed-loop systems are considered. It is shown that using the standard setup known from feedback control, it is possible to formulate fault diagnosis problems based on a performance index in this general standard setup. It is also shown...

  6. Fault tolerant computing systems

    CERN Document Server

    Randell, B

    1981-01-01

    Fault tolerance involves the provision of strategies for error detection, damage assessment, fault treatment and error recovery. A survey is given of the different sorts of strategies used in highly reliable computing systems, together with an outline of recent research on the problems of providing fault tolerance in parallel and distributed computing systems. (15 refs).

  7. Fault Tolerant Control Systems

    DEFF Research Database (Denmark)

    Bøgh, S. A.

    was to avoid a total close-down in case of the most likely faults. The second was a fault tolerant attitude control system for a micro satellite where the operation of the system is mission critical. The purpose was to avoid hazardous effects from faults and maintain operation if possible. A method...

  8. Geoethical implications in the L'Aquila case: scientific knowledge and communication

    Science.gov (United States)

    Di Capua, Giuseppe

    2013-04-01

    On October 22nd 2012, three and a half years after the earthquake that destroyed the city of L'Aquila (central Italy), killing more than 300 people and wounding about 1,500, a landmark judgment for the scientific research established the condemnation of six members of the Major Risks Committee of the Italian Government and a researcher of INGV (Istituto Nazionale di Geofisica e Vulcanologia), called to provide information about the evolution of the seismic sequence. The judge held that these Geoscientists were negligent during the meeting of 31st March 2009, convened to discuss the scientific aspects of the seismic risk of this area, affected by a long seismic sequence, also in the light of repeated warnings about the imminence of a strong earthquake, on the base of measurements of radon gas by an Italian independent technician, transmitted to the population by mass-media. Without going into the legal aspects of the criminal proceedings, this judgment strikes for the hardness of the condemnation to be paid by the scientists (six years of imprisonment, perpetual disqualification from public office and legal disqualification during the execution of the penalty, compensation for victims up to several hundred thousands of Euros). Some of them are scientists known worldwide for their proven skills, professionalism and experience. In conclusion, these scientists were found guilty of having contributed to the death of many people, because they have not communicated in an appropriate manner all available information on the seismic hazard and vulnerability of the area of L'Aquila. This judgment represents a watershed in the way of looking at the social role of geoscientists in the defense against natural hazards and their responsibility towards the people. But, in what does this responsibility consist of? It consists of the commitment to conduct an updated and reliable scientific research, which provides for a detailed analysis of the epistemic uncertainty for a more

  9. Deep Seated Gravitational Slope Deformations triggered by the 2009 L'Aquila earthquake

    Science.gov (United States)

    Moro, Marco; Saroli, Michele; Chini, Marco; Salvi, Stefano; Stramondo, Salvatore

    2010-05-01

    We investigated the surface effects of the April 6th, 2009, L'Aquila earthquake (Mw 6.3), using geological investigations and Synthetic Aperture Radar (SAR) data obtained by new High Resolution COSMO-SkyMed SAR2000. The earthquake affected a large area in Central Italy causing strong damage to cities and villages in the epicentral region. Deep-seated Gravitational Slope Deformation (DGSD) triggered by the earthquake shaking have been detected and quantified in term of their coseismic movement. DGSD are gravity-driven ground movements occurring on large (1-5 km length, 100-500 m depth and width) rock volumes. We exploited the capabilities of the new High Resolution COSMO-SkyMed SAR2000 instrument, using the Differential SAR Interferometry (DInSAR) technique. We used a right ascending, Stripmap mode (35° incidence angle), coseimic image pair (April 4 - April 12) to measure the surface displacement. We removed the topographic phase contribution using a detailed DEM at 5-m resolution. Fringe complexities, not directly attributed to the main tectonic pattern, have been detected in local areas. Geomorphological and geological analysis allow us to attribute such fringe patterns to ground displacement occurred along two different DGSD, one close to Roio Piano village, and the other North of the Barisciano village. The first DGSD is interpreted as a sackung induced by the particular structural setting (down dip strata) and the high relief energy, whilst the second one appears to be a lateral spread of carbonatic bedrock. We unwrapped the interferogram to measure the local movements, and found 4-5 cm of LOS (Line Of Sight) displacement in both areas. The DGSD movement was triggered by the earthquake ground shaking, and, although in this case it did not result in a catastrophic collapse of the rock masses, it certainly indicates the presence of an increased ground shaking hazard in these areas. The L'Aquila earthquake is the second case study where the seismic triggering of

  10. SEISMIC SITE RESPONSE ESTIMATION IN THE NEAR SOURCE REGION OF THE 2009 L’AQUILA, ITALY, EARTHQUAKE

    Science.gov (United States)

    Bertrand, E.; Azzara, R.; Bergamashi, F.; Bordoni, P.; Cara, F.; Cogliano, R.; Cultrera, G.; di Giulio, G.; Duval, A.; Fodarella, A.; Milana, G.; Pucillo, S.; Régnier, J.; Riccio, G.; Salichon, J.

    2009-12-01

    The 6th of April 2009, at 3:32 local time, a Mw 6.3 earthquake hit the Abruzzo region (central Italy) causing more than 300 casualties. The epicenter of the earthquake was 95km NE of Rome and 10km from the center of the city of L’Aquila, the administrative capital of the Abruzzo region. This city has a population of about 70,000 and was severely damaged by the earthquake, the total cost of the buildings damage being estimated around 3 Bn €. Historical masonry buildings particularly suffered from the seismic shaking, but some reinforced concrete structures from more modern construction were also heavily damaged. To better estimate the seismic solicitation of these structures during the earthquake, we deployed temporary arrays in the near source region. Downtown L’Aquila, as well as a rural quarter composed of ancient dwelling-centers located western L’Aquila (Roio area), have been instrumented. The array set up downtown consisted of nearly 25 stations including velocimetric and accelerometric sensors. In the Roio area, 6 stations operated for almost one month. The data has been processed in order to study the spectral ratios of the horizontal component of ground motion at the soil site and at a reference site, as well as the spectral ratio of the horizontal and the vertical movement at a single recording site. Downtown L’Aquila is set on a Quaternary fluvial terrace (breccias with limestone boulders and clasts in a marly matrix), which forms the left bank of the Aterno River and slopes down in the southwest direction towards the Aterno River. The alluvial are lying on lacustrine sediments reaching their maximum thickness (about 250m) in the center of L’Aquila. After De Luca et al. (2005), these quaternary deposits seem to lead in an important amplification factor in the low frequency range (0.5-0.6 Hz). However, the level of amplification varies strongly from one point to the other in the center of the city. This new experimentation allows new and more

  11. MORSE Monte Carlo code

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, S.N.

    1984-01-01

    The MORSE code is a large general-use multigroup Monte Carlo code system. Although no claims can be made regarding its superiority in either theoretical details or Monte Carlo techniques, MORSE has been, since its inception at ORNL in the late 1960s, the most widely used Monte Carlo radiation transport code. The principal reason for this popularity is that MORSE is relatively easy to use, independent of any installation or distribution center, and it can be easily customized to fit almost any specific need. Features of the MORSE code are described.

  12. Information Based Fault Diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2008-01-01

    Fault detection and isolation, (FDI) of parametric faults in dynamic systems will be considered in this paper. An active fault diagnosis (AFD) approach is applied. The fault diagnosis will be investigated with respect to different information levels from the external inputs to the systems....... These inputs are disturbance inputs, reference inputs and auxilary inputs. The diagnosis of the system is derived by an evaluation of the signature from the inputs in the residual outputs. The changes of the signatures form the external inputs are used for detection and isolation of the parametric faults....

  13. Fault-Tree Compiler

    Science.gov (United States)

    Butler, Ricky W.; Boerschlein, David P.

    1993-01-01

    Fault-Tree Compiler (FTC) program, is software tool used to calculate probability of top event in fault tree. Gates of five different types allowed in fault tree: AND, OR, EXCLUSIVE OR, INVERT, and M OF N. High-level input language easy to understand and use. In addition, program supports hierarchical fault-tree definition feature, which simplifies tree-description process and reduces execution time. Set of programs created forming basis for reliability-analysis workstation: SURE, ASSIST, PAWS/STEM, and FTC fault-tree tool (LAR-14586). Written in PASCAL, ANSI-compliant C language, and FORTRAN 77. Other versions available upon request.

  14. Earthquake fault superhighways

    Science.gov (United States)

    Robinson, D. P.; Das, S.; Searle, M. P.

    2010-10-01

    Motivated by the observation that the rare earthquakes which propagated for significant distances at supershear speeds occurred on very long straight segments of faults, we examine every known major active strike-slip fault system on land worldwide and identify those with long (> 100 km) straight portions capable not only of sustained supershear rupture speeds but having the potential to reach compressional wave speeds over significant distances, and call them "fault superhighways". The criteria used for identifying these are discussed. These superhighways include portions of the 1000 km long Red River fault in China and Vietnam passing through Hanoi, the 1050 km long San Andreas fault in California passing close to Los Angeles, Santa Barbara and San Francisco, the 1100 km long Chaman fault system in Pakistan north of Karachi, the 700 km long Sagaing fault connecting the first and second cities of Burma, Rangoon and Mandalay, the 1600 km Great Sumatra fault, and the 1000 km Dead Sea fault. Of the 11 faults so classified, nine are in Asia and two in North America, with seven located near areas of very dense populations. Based on the current population distribution within 50 km of each fault superhighway, we find that more than 60 million people today have increased seismic hazards due to them.

  15. Double Fault Detection of Cone-Shaped Redundant IMUs Using Wavelet Transformation and EPSA

    Directory of Open Access Journals (Sweden)

    Wonhee Lee

    2014-02-01

    Full Text Available A model-free hybrid fault diagnosis technique is proposed to improve the performance of single and double fault detection and isolation. This is a model-free hybrid method which combines the extended parity space approach (EPSA with a multi-resolution signal decomposition by using a discrete wavelet transform (DWT. Conventional EPSA can detect and isolate single and double faults. The performance of fault detection and isolation is influenced by the relative size of noise and fault. In this paper; the DWT helps to cancel the high frequency sensor noise. The proposed technique can improve low fault detection and isolation probability by utilizing the EPSA with DWT. To verify the effectiveness of the proposed fault detection method Monte Carlo numerical simulations are performed for a redundant inertial measurement unit (RIMU.

  16. Quantum Monte Carlo simulation

    OpenAIRE

    Wang, Yazhen

    2011-01-01

    Contemporary scientific studies often rely on the understanding of complex quantum systems via computer simulation. This paper initiates the statistical study of quantum simulation and proposes a Monte Carlo method for estimating analytically intractable quantities. We derive the bias and variance for the proposed Monte Carlo quantum simulation estimator and establish the asymptotic theory for the estimator. The theory is used to design a computational scheme for minimizing the mean square er...

  17. Monte Carlo transition probabilities

    OpenAIRE

    Lucy, L. B.

    2001-01-01

    Transition probabilities governing the interaction of energy packets and matter are derived that allow Monte Carlo NLTE transfer codes to be constructed without simplifying the treatment of line formation. These probabilities are such that the Monte Carlo calculation asymptotically recovers the local emissivity of a gas in statistical equilibrium. Numerical experiments with one-point statistical equilibrium problems for Fe II and Hydrogen confirm this asymptotic behaviour. In addition, the re...

  18. Multiscale Documentation and Monitoring of L'aquila Historical Centre Using Uav Photogrammetry

    Science.gov (United States)

    Dominici, D.; Alicandro, M.; Rosciano, E.; Massimi, V.

    2017-05-01

    Nowadays geomatic techniques can guarantee not only a precise and accurate survey for the documentation of our historical heritage but also a solution to monitor its behaviour over time after, for example, a catastrophic event (earthquakes, landslides, ecc). Europe is trying to move towards harmonized actions to store information on cultural heritage (MIBAC with the ICCS forms, English heritage with the MIDAS scheme, etc) but it would be important to provide standardized methods in order to perform measuring operations to collect certified metric data. The final result could be a database to support the entire management of the cultural heritage and also a checklist of "what to do" and "when to do it". The wide range of geomatic techniques provides many solutions to acquire, to organize and to manage data at a multiscale level: high resolution satellite images can provide information in a short time during the "early emergency" while UAV photogrammetry and laser scanning can provide digital high resolution 3D models of buildings, ortophotos of roofs and facades and so on. This paper presents some multiscale survey case studies using UAV photogrammetry: from a minor historical village (Aielli) to the centre of L'Aquila (Santa Maria di Collemaggio Church) from the post-emergency to now. This choice has been taken not only to present how geomatics is an effective science for modelling but also to present a complete and reliable way to perform conservation and/or restoration through precise monitoring techniques, as shown in the third case study.

  19. Rubble masonry response under cyclic actions: The experience of L’Aquila city (Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Fonti, Roberta, E-mail: roberta.fonti@tum.de; Barthel, Rainer, E-mail: r.barthel@lrz.tu-muenchen.de [TUM University, Chair of Structural Design, Arcisstraße 21, 80333 Munich (Germany); Formisano, Antonio, E-mail: antoform@unina.it [University of Naples “Federico II”, DIST Department, P.le V. Tecchio, 80, 80125 Naples (Italy); Borri, Antonio, E-mail: antonio.borri@unipg.it [University of Perugia, Department of Engineering, Via G. Duranti 95, 06125 Perugia (Italy); Candela, Michele, E-mail: ing.mcandela@libero.it [University of Reggio Calabria, PAU Department, Salita Melissari 1, 89124 Reggio Calabria (Italy)

    2015-12-31

    Several methods of analysis are available in engineering practice to study old masonry constructions. Two commonly used approaches in the field of seismic engineering are global and local analyses. Despite several years of research in this field, the various methodologies suffer from a lack of comprehensive experimental validation. This is mainly due to the difficulty in simulating the many different kinds of masonry and, accordingly, the non-linear response under horizontal actions. This issue can be addressed by examining the local response of isolated panels under monotonic and/or alternate actions. Different testing methodologies are commonly used to identify the local response of old masonry. These range from simplified pull-out tests to sophisticated in-plane monotonic tests. However, there is a lack of both knowledge and critical comparison between experimental validations and numerical simulations. This is mainly due to the difficulties in implementing irregular settings within both simplified and advanced numerical analyses. Similarly, the simulation of degradation effects within laboratory tests is difficult with respect to old masonry in-situ boundary conditions. Numerical models, particularly on rubble masonry, are commonly simplified. They are mainly based on a kinematic chain of rigid blocks able to perform different “modes of damage” of structures subjected to horizontal actions. This paper presents an innovative methodology for testing; its aim is to identify a simplified model for out-of-plane response of rubbleworks with respect to the experimental evidence. The case study of L’Aquila district is discussed.

  20. The genome sequence of a widespread apex predator, the golden eagle (Aquila chrysaetos.

    Directory of Open Access Journals (Sweden)

    Jacqueline M Doyle

    Full Text Available Biologists routinely use molecular markers to identify conservation units, to quantify genetic connectivity, to estimate population sizes, and to identify targets of selection. Many imperiled eagle populations require such efforts and would benefit from enhanced genomic resources. We sequenced, assembled, and annotated the first eagle genome using DNA from a male golden eagle (Aquila chrysaetos captured in western North America. We constructed genomic libraries that were sequenced using Illumina technology and assembled the high-quality data to a depth of ∼40x coverage. The genome assembly includes 2,552 scaffolds >10 Kb and 415 scaffolds >1.2 Mb. We annotated 16,571 genes that are involved in myriad biological processes, including such disparate traits as beak formation and color vision. We also identified repetitive regions spanning 92 Mb (∼6% of the assembly, including LINES, SINES, LTR-RTs and DNA transposons. The mitochondrial genome encompasses 17,332 bp and is ∼91% identical to the Mountain Hawk-Eagle (Nisaetus nipalensis. Finally, the data reveal that several anonymous microsatellites commonly used for population studies are embedded within protein-coding genes and thus may not have evolved in a neutral fashion. Because the genome sequence includes ∼800,000 novel polymorphisms, markers can now be chosen based on their proximity to functional genes involved in migration, carnivory, and other biological processes.

  1. Rubble masonry response under cyclic actions: The experience of L'Aquila city (Italy)

    Science.gov (United States)

    Fonti, Roberta; Barthel, Rainer; Formisano, Antonio; Borri, Antonio; Candela, Michele

    2015-12-01

    Several methods of analysis are available in engineering practice to study old masonry constructions. Two commonly used approaches in the field of seismic engineering are global and local analyses. Despite several years of research in this field, the various methodologies suffer from a lack of comprehensive experimental validation. This is mainly due to the difficulty in simulating the many different kinds of masonry and, accordingly, the non-linear response under horizontal actions. This issue can be addressed by examining the local response of isolated panels under monotonic and/or alternate actions. Different testing methodologies are commonly used to identify the local response of old masonry. These range from simplified pull-out tests to sophisticated in-plane monotonic tests. However, there is a lack of both knowledge and critical comparison between experimental validations and numerical simulations. This is mainly due to the difficulties in implementing irregular settings within both simplified and advanced numerical analyses. Similarly, the simulation of degradation effects within laboratory tests is difficult with respect to old masonry in-situ boundary conditions. Numerical models, particularly on rubble masonry, are commonly simplified. They are mainly based on a kinematic chain of rigid blocks able to perform different "modes of damage" of structures subjected to horizontal actions. This paper presents an innovative methodology for testing; its aim is to identify a simplified model for out-of-plane response of rubbleworks with respect to the experimental evidence. The case study of L'Aquila district is discussed.

  2. Ultraviolet Spectroscopic Study of BY Circini and V 1425 Aquilae from IUE Satellite

    Indian Academy of Sciences (India)

    M. R. Sanad

    2014-12-01

    We present the ultraviolet spectra of two classical novae, BY Circini 1995 and V1425 Aquilae 1995, using observations obtained with the International Ultraviolet Explorer (IUE). The outflow velocity of the ionized ejecta was calculated to be 2100–2700 km s-1 and 1600–1900 km s-1 (FWHM) for BY Cir and V1425 Aql, respectively. The models generated by Jose & Hernanz (1998, ApJ, 494, 680) indicate that BY Cir is a CO4/CO5 nova with WD mass of ∼ 1.15⊙, while V1425 Aql is a CO2/CO3 nova with WD mass of ∼ 0.9⊙. Different profiles of BY Cir and V1425 Aql showing variations of line fluxes at different orbital phases are presented. This paper focuses on the calculated spectral line fluxes for the N III emission line at 1750 Å and the C III emission line at 1909 Å, produced in the expanding shell of ionized gas. Our results show that there are variations of line fluxes with time. We attribute these spectral variations in line fluxes to the variations of both density and temperature in the line-emitting regions as a result of the inhomogeneous ejecta. The variable line fluxes, ultraviolet luminosities and accretion rates support a model of the ejecta consisting of an optically thin dust shell and hot ionized gas.

  3. The 6 April 2009 earthquake at L'Aquila: a preliminary analysis of magnetic field measurements

    Directory of Open Access Journals (Sweden)

    U. Villante

    2010-02-01

    Full Text Available Several investigations reported the possible identification of anomalous geomagnetic field signals prior to earthquake occurrence. In the ULF frequency range, candidates for precursory signatures have been proposed in the increase in the noise background and polarization parameter (i.e. the ratio between the amplitude/power of the vertical component and that one of the horizontal component, in the changing characteristics of the slope of the power spectrum and fractal dimension, in the possible occurrence of short duration pulses. We conducted, with conventional techniques of data processing, a preliminary analysis of the magnetic field observations performed at L'Aquila during three months preceding the 6 April 2009 earthquake, focusing attention on the possible occurrence of features similar to those identified in previous events. Within the limits of this analysis, we do not find compelling evidence for any of the features which have been proposed as earthquake precursors: indeed, most of aspects of our observations (which, in some cases, appear consistent with previous findings might be interpreted in terms of the general magnetospheric conditions and/or of different sources.

  4. Nova V1425 Aquilae 1995 The Early Appearance of Accretion Processes in An Intermediate Polar Candidate

    CERN Document Server

    Retter, A; Kovo-Kariti, O

    1997-01-01

    Continuous CCD photometry of Nova Aquilae 1995 was performed through the standard B,V,R and I filters during three nights in 1995 and with the I filter during 18 nights in 1996. The power spectrum of the 1996 data reveals three periodicities in the light curve: 0.2558 d, 0.06005 d and 0.079 d, with peak-to-peak amplitudes of about 0.012, 0.014 and 0.007 mag. respectively. The two shorter periods are absent from the power spectrum of the 1995 light curve, while the long one is probably already present in the light curve of that year. We propose that V1425 Aql should be classified as an Intermediate - Polar CV. Accordingly the three periods are interpreted as the orbital period of the underlying binary system, the spin period of the magnetic white dwarf and the beat period between them. Our results suggest that no later than 15 months after the outburst of the nova, accretion processes are taking place in this stellar system. Matter is being transferred from the cool component, most likely through an accretion ...

  5. Headache prevalence in the population of L'Aquila (Italy) after the 2009 earthquake.

    Science.gov (United States)

    Guetti, Cristiana; Angeletti, Chiara; Papola, Roberta; Petrucci, Emiliano; Ursini, Maria Laura; Ciccozzi, Alessandra; Marinangeli, Franco; Paladini, Antonella; Varrassi, Giustino

    2011-04-01

    Stress induced by the events of daily life is considered a major factor in pathogenesis of primary tension-type headache. Little is known about the impact that could have a more stressful event, like a natural disaster, both in patients with chronic headache, both in people that do not had headache previously. The aim of the present study was to observe the prevalence of headache in the population following the devastating earthquake that affected the province of L'Aquila on April 6, 2009. The study population was conducted in four tent cities (Onna, Bazzano, Tempera-St. Biagio, Paganica). Sanitary access is recorded in the registers of medical triage, in the first 5 weeks, after the April 6, 2009. The prevalence of primary headache presentation was 5.53% (95% CI 4.2-7.1), secondary headache was 2.82% (95% CI 1.9-4.9). Pain intensity, assessed by Numerical Rating Scale score showed a mean value of 7±1.1 (range 4-10). The drugs most used were the NSAIDs (46%) and paracetamol (36%), for impossibility of finding causal drugs. This study shows how more stressful events not only have an important role in determining acute exacerbation of chronic headache, but probably also play a pathogenic role in the emergence of primary headache. Also underlines the lack of diagnostic guidelines or operating protocols to early identify and treat headache in the emergency settings.

  6. Surveys with UAV photogrammetry: case studies in l'Aquila during the post-earthquake scenario

    Science.gov (United States)

    Alicandro, Maria; Dominici, Donatella; Massimini, Vincenzo

    2015-04-01

    The main advantages of using the UAV photogrammetry in a post-earthquake scenario it consist in the possibility to perform a complete documentation of the structures and infrastructures, eventually damaged by the earthquake, ensuring the safety of all operators during the data collection activities. The aspect of safety and accessibility in the area represents in fact a crucial aspect after an earthquake and sometimes some areas may result directly inaccessible, while at the same time it's necessary to collect data in order to monitor and evaluate the damages. The development of new algorithms in the field of Computer Vision drastically improved the degree of automation of the 3D point clouds generation using the photogrammetry techniques. In addition, techniques of data acquisition using the UAV allows to obtain 3D model with the highest as possible resolution especially with respect to the conventional satellite or aerial photogrammetry. These advantages make the UAV photogrammetry highly suitable for the surveys in a geo-hazard contexts as the post-earthquake. Some results of surveys with the techniques of UAV Photogrammetry and performed after L'Aquila Earthquake occurred in 2009 will be presented and discussed.

  7. In connection with identification of VLF emissions before L'Aquila earthquake

    Directory of Open Access Journals (Sweden)

    M. K. Kachakhidze

    2012-04-01

    Full Text Available The present paper deals with an attempt to check the theoretical model of self-generated seismo-electromagnetic oscillations of LAI system on the basis of retrospective data.

    Application of the offered simple model enables one to explain qualitatively the mechanism of VLF electromagnetic emission initiated in the process of an earthquake preparation. Besides, the model enables us to associate telluric character geoelectric and geomagnetic perturbations incited by rock polarization and self-generated electromagnetic oscillations of lithosphere-atmosphere system.

    L'Aquila earthquake taken as an example to isolate reliably the Earth VLF emission from the magnetospheric electromagnetic emission of the same frequency range, MHD criterion is offered together with geomagnetic activity indexes.

    On the basis of the considered three earthquakes, according to the opinion of authors the model of self-generated seismo-electromagnetic oscillations of the LAI system will enable us to approach the problem of resolution of earthquake prediction with certain accuracy.

  8. A Decrease in Sex Ratio at Birth Nine Months after the Earthquake in L'Aquila

    Directory of Open Access Journals (Sweden)

    A. D'Alfonso

    2012-01-01

    Full Text Available Introduction. Multiple factors influence the secondary sex ratio (SSR including stress, which appears to affect mainly the males born. Objective. We evaluate the effects of the earthquake in L'Aquila on the SSR. Materials and Methods. The SSR for the first six months of 2010 was compared to that of the same period of 2008. The chi-square test and Fisher's test were used for the statistical analysis. Results. Nine months after the earthquake, an important reduction in the SSR was recorded: January 2010 versus January 2008 =0.62 versus 0.96. An overall fall in the SSR was also recorded when the first 3 months of 2010 were compared to the first three months of 2008: 0,82 versus 1,11. When the first three months of 2010 were compared with the second three months of 2010, a statistically significant increase of the sex ratio at birth was noted (0,82 versus 1,27.

  9. Evolution of the radio - X-ray coupling throughout an entire outburst of Aquila X-1

    CERN Document Server

    Miller-Jones, J C A; Altamirano, D; Tudose, V; Migliari, S; Dhawan, V; Fender, R P; Garrett, M A; Heinz, S; Körding, E G; Krimm, H A; Linares, M; Maitra, D; Markoff, S; Paragi, Z; Remillard, R A; Rupen, M P; Rushton, A; Russell, D M; Sarazin, C L; Spencer, R E

    2010-01-01

    The 2009 November outburst of the neutron star X-ray binary Aquila X-1 was observed with unprecedented radio coverage and simultaneous pointed X-ray observations, tracing the radio emission around the full X-ray hysteresis loop of the outburst for the first time. We use these data to discuss the disc-jet coupling, finding the radio emission to be consistent with being triggered at state transitions, both from the hard to the soft spectral state and vice versa. Our data appear to confirm previous suggestions of radio quenching in the soft state above a threshold X-ray luminosity of about 10% of the Eddington luminosity. We also present the first detections of Aql X-1 with Very Long Baseline Interferometry (VLBI), showing that any extended emission is relatively diffuse, and consistent with steady jets rather than arising from discrete, compact knots. In all cases where multi-frequency data were available, the source radio spectrum is consistent with being flat or slightly inverted, suggesting that the internal...

  10. STATUS BAKU MUTU AIR LAUT PERAIRAN TELUK AMBON LUAR UNTUK WISATA BAHARI KAPAL TENGGELAM SS AQUILA

    Directory of Open Access Journals (Sweden)

    Guntur Adhi Rahmawan

    2017-09-01

    Full Text Available Ambon Bay waters consist of two parts, Inner Ambon Bay and Outer Ambon Bay separated by a gap that is narrow and shallow. Ambon Bay has a lot of functionality and usability both in transportation, conservation, and tourism. The existence of one of the sites SS. Aquila sinking ship that sank since May 27, 1958, became one of the tourist attraction diving in Ambon Bay. Determination of water pollution index Ambon Bay becomes very important to do as support material and development of sea travel. Determining pollution index is done by direct measurement using the sea water quality parameters Water Quality Checker (DKK TOA WQC Type-24, as well as laboratory analysis to determine the chemical parameters of seawater (pH, TSS, salinity, turbidity, oil, grease. The results showed that the waters of the Bay of Ambon Affairs based on some parameters water quality standard for marine tourism is still included in accordance with the standard criteria by Keputusan Menteri Negara Lingkungan Hidup Nomor: 51 Tahun 2004 on Guidelines for Determination of Water Quality Status.

  11. Surgical treatment of bumblefoot in a captive golden eagle (Aquila chrysaetos

    Directory of Open Access Journals (Sweden)

    Saeed Nazifi

    2012-03-01

    Full Text Available The golden eagle is one of the world's largest living birds. Footpad dermatitis, also known as plantar pododermatitis or bumblefoot, is a condition characterized by lesions due to contact with unhealthy "perching" conditions, such as plastic perches, sharp-cornered perches on the ventral footpad of birds. A young female golden eagle (Aquila chrysaetos in Fars province of Iran was presented to veterinary clinics of Shiraz University with clinical signs of lameness. The bird was examined clinically and a variety of complementary diagnostic procedures such as blood analysis, X-ray and bacteriological culture were performed. Then a surgical method was pick out for removing of scab, pus and necrotic tissues from abscess on the plantar aspect of bird's feet and healing the skin of area. After surgery, specific bandage, systemic antibiotics and vitamins were used. Corynebacterium, a gram negative bacterium, was isolated in the pus from the abscess. After the surgical operation, swelling in the digital pad reduced, the skin of pad healed and the signs of lameness vanished. To prevent developing bumblefoot, good bedding for proper "perching" conditions is necessary. Additionally, vitamin therapy to promote a healthy integument is advised.

  12. Surgical treatment of bumblefoot in a captive golden eagle (Aquila chrysaetos).

    Science.gov (United States)

    Poorbaghi, Seyedeh Leila; Javdani, Moosa; Nazifi, Saeed

    2012-01-01

    The golden eagle is one of the world's largest living birds. Footpad dermatitis, also known as plantar pododermatitis or bumblefoot, is a condition characterized by lesions due to contact with unhealthy "perching" conditions, such as plastic perches, sharp-cornered perches on the ventral footpad of birds. A young female golden eagle (Aquila chrysaetos) in Fars province of Iran was presented to veterinary clinics of Shiraz University with clinical signs of lameness. The bird was examined clinically and a variety of complementary diagnostic procedures such as blood analysis, X-ray and bacteriological culture were performed. Then a surgical method was pick out for removing of scab, pus and necrotic tissues from abscess on the plantar aspect of bird's feet and healing the skin of area. After surgery, specific bandage, systemic antibiotics and vitamins were used. Corynebacterium, a gram negative bacterium, was isolated in the pus from the abscess. After the surgical operation, swelling in the digital pad reduced, the skin of pad healed and the signs of lameness vanished. To prevent developing bumblefoot, good bedding for proper "perching" conditions is necessary. Additionally, vitamin therapy to promote a healthy integument is advised.

  13. Seismic monitoring by piezoelectric accelerometers of a damaged historical monument in downtown L’Aquila

    Directory of Open Access Journals (Sweden)

    Giuseppe Di Giulio

    2015-03-01

    Full Text Available We show the preliminary seismic monitoring of a historical church in L’Aquila (central Italy, which was strongly damaged by the 2009 seismic sequence. This structure, S. Maria del Suffragio church, suffered the collapse of a great part of the dome during the April 6th 2009 Mw 6.1 earthquake. In this paper, recordings of ambient noise and local earthquakes have been analyzed. The seismic data were recorded by means of a dynamic monitoring system (19 mono-directional and 3 tri-directional piezoelectric accelerometers and of two velocimeters, with all the instruments installed into the church. The aim of this research is the evaluation of the performance of the accelerometers of the monitoring system in case of low-amplitude vibrations. Simple techniques of analysis commonly employed in the seismic characterization of buildings have been applied. The reliability of the in-situ data was evaluated and the main modal parameters (natural frequencies and damping ratio of the church were presented.

  14. Morphostructural study of the Belledonne faults system (French Alps).

    Science.gov (United States)

    Billant, Jérémy; Bellier, Olivier; Hippolyte, Jean-Claude; Godard, Vincent; Manchuel, Kevin

    2016-04-01

    The NE trending Belledonne faults system, located in the Alps, is a potentially active faults system that extends from the Aiguilles Rouges and Mont Blanc massifs in the NE to the Vercors massif in the SW (subalpine massifs). It includes the Belledonne border fault (BBF), defined by an alignment of micro earthquakes (ML≤3.5) along the eastern part of the Grésivaudan valley (Thouvenot et al., 2003). Focal mechanisms and their respective depths tend to confirm a dextral strike-slip faulting at crustal scale. In the scope of the Sigma project (http://projet-sigma.com/index.html, EDF), this study aims at better constraining the geometry, kinematic and seismogenic potential of the constitutive faults of the Belledonne fault system, by using a multidisciplinary approach that includes tectonics, geomorphology and geophysics. Fault kinematic analysis along the BBF (Billant et al., 2015) and the Jasneuf fault allows the determination of a strike-slip tectonic regime characterised by an ENE trending σ1 stress axes, which is consistent with stress state deduced from the focal mechanisms. Although no morphological anomalies could be related to recent faulting along the BBF, new clues of potential Quaternary deformations were observed along the other faults of the system: -right lateral offset of morphologic markers (talwegs...) along the NE trending Arcalod fault located at the north-eastern terminations of the BBF; -left lateral offset of the valley formed by the Isère glacier along the NW trending Brion fault which is consistent with its left-lateral slip inferred from the focal mechanisms; -fault scarps and right lateral offsets of cliffs bordering a calcareous plateau and talwegs along the four fault segments of the NE trending Jasneuf fault located at the south-western termination of the BBF in the Vercors massif. Some offsets were measured using a new method that does not require the identification of piercing points and take advantage of the high resolution

  15. Insight on fault segmentation, linkage and hazard from the 2016 Mw6.2 Amatrice earthquake (central Italy)

    Science.gov (United States)

    Walters, R. J.; Gregory, L. C.; Wedmore, L. N. J.; Craig, T. J.; Elliott, J. R.; Wilkinson, M. W.; McCaffrey, K. J. W.; Michetti, A.; Vittori, E.; Livio, F.; Iezzi, F.; Chen, J.; Li, Z.; Roberts, G.

    2016-12-01

    We investigate the 2016 Mw6.2 Amatrice earthquake (central Italy) with a combination of bodywave seismology, field measurements and satellite geodesy, and show that the earthquake ruptured across two normal faults that had previously been identified as separate structures. Our coseismic source model, obtained from GPS and InSAR data, shows slip in two major patches, taking place over a total length of 20 km, and mainly constrained to shallow (2-7 km) depths. Our model shows that the highest slip was focussed on the unknown linking section between the mapped Laga and Vettore faults. Our model predicts primary surface rupture to be present only on the Vettore fault, in agreement with our field observations. Our seismological model has a simple source-time function, implying that within the resolution of the data, the rupture proceeded without pause across the linking section between the Vettore and Laga faults. Both faults were previously identified as active, but field mapping, remote sensing data, geomorphology, and Holocene slip rates had all been used to support the idea that the faults were separate structures. Each had been thought capable of producing an earthquake with MWItaly; the destructive 1980 MW6.9 Irpinia earthquake in southern Italy was composed of multiple MW6.2-6.5 sub-events on four separate segments. Each of the MW6.7-7 largest known events in central Italy; the 1703 Norcia and L'Aquila earthquakes and the 1915 Avezzano earthquake, are also thought to have involved multi-fault rupture. MW>7 earthquakes are not reported in the long and detailed historical and palaeoseismological record of the region, but more study is needed to understand their absence, and to ensure we can rule-out such large events in future. This earthquake prompts reassessment of the state of linkage between other faults in central Italy, with an aim to better assess the increased seismic hazard posed by multi-fault ruptures.

  16. [Health status and access to health services by the population of L'Aquila (Abruzzo Region, Italy) six years after the earthquake].

    Science.gov (United States)

    Altobelli, Emma; Vittorini, Pierpaolo; Leuter, Cinzia; Bianchini, Valeria; Angelone, Anna Maria; Aloisio, Federica; Cofini, Vincenza; Zazzara, Francesca; Di Orio, Ferdinando

    2016-01-01

    Natural disasters, such as the earthquake that occurred in the province of L'Aquila in central Italy, in 2009, generally increase the demand for healthcare. A survey was conducted to assess perception of health status an d use of health services in a sample of L'Aquila's resident population, five years after the event, and in a comparison population consisting of a sample of the resident population of Avezzano, a town in the same region, not affected by the earthquake. No differences were found in perception of health status between the two populations. Both groups reported difficulties in accessing specialized healthcare and rehabilitation services.

  17. Deep reaching versus vertically restricted Quaternary normal faults: Implications on seismic potential assessment in tectonically active regions: Lessons from the middle Aterno valley fault system, central Italy

    Science.gov (United States)

    Falcucci, E.; Gori, S.; Moro, M.; Fubelli, G.; Saroli, M.; Chiarabba, C.; Galadini, F.

    2015-05-01

    We investigate the Middle Aterno Valley fault system (MAVF), a poorly investigated seismic gap in the central Apennines, adjacent to the 2009 L'Aquila earthquake epicentral area. Geological and paleoseismological analyses revealed that the MAVF evolved through hanging wall splay nucleation, its main segment moving at 0.23-0.34 mm/year since the Middle Pleistocene; the penultimate activation event occurred between 5388-5310 B.C. and 1934-1744 B.C., the last event after 2036-1768 B.C. and just before 1st-2nd century AD. These data define hard linkage (sensu Walsh and Watterson, 1991; Peacock et al., 2000; Walsh et al., 2003, and references therein) with the contiguous Subequana Valley fault segment, able to rupture in large magnitude earthquakes (up to 6.8), that did not rupture since about two millennia. By the joint analysis of geological observations and seismological data acquired during to the 2009 seismic sequence, we derive a picture of the complex structural framework of the area comprised between the MAVF, the Paganica fault (the 2009 earthquake causative fault) and the Gran Sasso Range. This sector is affected by a dense array of few-km long, closely and regularly spaced Quaternary normal fault strands, that are considered as branches of the MAVF northern segment. Our analysis reveals that these structures are downdip confined by a decollement represented by to the presently inactive thrust sheet above the Gran Sasso front limiting their seismogenic potential. Our study highlights the advantage of combining Quaternary geological field analysis with high resolution seismological data to fully unravel the structural setting of regions where subsequent tectonic phases took place and where structural interference plays a key role in influencing the seismotectonic context; this has also inevitably implications for accurately assessing seismic hazard of such structurally complex regions.

  18. Satellite tracking of two lesser spotted eagles Aquila pomarina, migrating from Namibia

    Science.gov (United States)

    Meyburg, B.-U.; Ellis, D.H.; Meyburg, C.; Mendelsohn, J.; Scheller, W.

    2001-01-01

    One immature and one subadult Lesser Spotted Eagle, Aquila pomarina, were followed by satellite telemetry from their non-breeding areas in Namibia. Both birds were fitted with transmitters (PTTs) in February 1994 and tracked, the immature for six months and two weeks, over distances of 10084 and 16773 km, respectively. During their time in Namibia both birds? movements were in response to good local rainfall. The immature eagle left Namibia at the end of February, the subadult at the end of March. They flew to their respective summer quarters in Hungary and the Ukraine, arriving there 2.5 and 1.5 months later than the breeding adults. The immature eagle took over two months longer on the homeward journey than a breeding male followed by telemetry in a previous study. On returning, the immature eagle followed the narrow flightpath through Africa used by other Lesser Spotted Eagles on their outward migration. It reached this corridor, which runs roughly between longitudes 31? and 36? East from Suez to Lake Tanganyika, veering from the shortest route in a direction east-northeast through Angola and Zambia to the southern end of Lake Tanganyika. The route taken by the subadult bird on its return migration differed markedly from that of all Lesser Spotted Eagles tracked to date, running further west through the Democratic Republic of Congo where, level with the equator, it flew over the eastern rainforest of that country. The outward migration, however, followed the same corridor and coincided in time with the migration of adults.

  19. Quantification and Origin of the Anomalous CO2 Release Accompanying L'Aquila 2009 Earthquakes

    Science.gov (United States)

    Chiodini, G.; Atzori, S.; Brunori, C. A.; Caliro, S.; Cardellini, C.; Di Luccio, F.; Frondini, F.; Rosiello, A.; Selva, J.; Ventura, G.

    2016-12-01

    Deep pressurised pockets of CO2 were recognised to be involved in two seismic crisis of the Apennines that preceded the Amatrice earthquake: the 1997 Umbria-Marche and the 2009 L'Aquila earthquakes (LAE). Here we focus on the LAE that in 2009 caused 309 victims, 1600 injured people and 80000 displaced persons. A previous investigation highlighted that important amounts of deeply derived CO2 enter in the two aquifers outcropping in the LAE area. Here, we update the previous dataset with the results of other eight campaigns, the last of which in September 2015, with the aim of evaluating any variation in the flux of deep CO2 related to the 2009 earthquakes. This long time series of chemical and isotopic compositions of the main springs in the area highlights an evident anomalous CO2 release associated with the earthquakes. In particular, starting from the date of the main shock, we observed an anomalous release of CO2 that lasted for years and involved hundred thousands tonnes of deeply derived gas. In order to interpret this anomaly we re-considered DinSAR data discovering that a 4 years long inflation preceded the LAE. We argue that the LAE event was anticipated by a years-long deep pressurization stage. Few months before the LAE, concurrently with the beginning of the seismicity, the ground movement changed from inflation to an accelerating deflection that culminated in the April 2009 mainshock. In our model, the observed anomalous release of deep CO2 in the years following the LAE is the last step of a process that began in 2005 causing the observed period of inflation of the area affected by the earthquakes.

  20. The Mitochondrial Genomes of Aquila fasciata and Buteo lagopus (Aves, Accipitriformes: Sequence, Structure and Phylogenetic Analyses.

    Directory of Open Access Journals (Sweden)

    Lan Jiang

    Full Text Available The family Accipitridae is one of the largest groups of non-passerine birds, including 68 genera and 243 species globally distributed. In the present study, we determined the complete mitochondrial sequences of two species of accipitrid, namely Aquila fasciata and Buteo lagopus, and conducted a comparative mitogenome analysis across the family. The mitogenome length of A. fasciata and B. lagopus are 18,513 and 18,559 bp with an A + T content of 54.2% and 55.0%, respectively. For both the two accipitrid birds mtDNAs, obvious positive AT-skew and negative GC-skew biases were detected for all 12 PCGs encoded by the H strand, whereas the reverse was found in MT-ND6 encoded by the L strand. One extra nucleotide'C'is present at the position 174 of MT-ND3 gene of A. fasciata, which is not observed at that of B. lagopus. Six conserved sequence boxes in the Domain II, named boxes F, E, D, C, CSBa, and CSBb, respectively, were recognized in the CRs of A. fasciata and B. lagopus. Rates and patterns of mitochondrial gene evolution within Accipitridae were also estimated. The highest dN/dS was detected for the MT-ATP8 gene (0.32493 among Accipitridae, while the lowest for the MT-CO1 gene (0.01415. Mitophylogenetic analysis supported the robust monophyly of Accipitriformes, and Cathartidae was basal to the balance of the order. Moreover, we performed phylogenetic analyses using two other data sets (two mitochondrial loci, and combined nuclear and mitochondrial loci. Our results indicate that the subfamily Aquilinae and all currently polytypic genera of this subfamily are monophyletic. These two novel mtDNA data will be useful in refining the phylogenetic relationships and evolutionary processes of Accipitriformes.

  1. The Mitochondrial Genomes of Aquila fasciata and Buteo lagopus (Aves, Accipitriformes): Sequence, Structure and Phylogenetic Analyses.

    Science.gov (United States)

    Jiang, Lan; Chen, Juan; Wang, Ping; Ren, Qiongqiong; Yuan, Jian; Qian, Chaoju; Hua, Xinghong; Guo, Zhichun; Zhang, Lei; Yang, Jianke; Wang, Ying; Zhang, Qin; Ding, Hengwu; Bi, De; Zhang, Zongmeng; Wang, Qingqing; Chen, Dongsheng; Kan, Xianzhao

    2015-01-01

    The family Accipitridae is one of the largest groups of non-passerine birds, including 68 genera and 243 species globally distributed. In the present study, we determined the complete mitochondrial sequences of two species of accipitrid, namely Aquila fasciata and Buteo lagopus, and conducted a comparative mitogenome analysis across the family. The mitogenome length of A. fasciata and B. lagopus are 18,513 and 18,559 bp with an A + T content of 54.2% and 55.0%, respectively. For both the two accipitrid birds mtDNAs, obvious positive AT-skew and negative GC-skew biases were detected for all 12 PCGs encoded by the H strand, whereas the reverse was found in MT-ND6 encoded by the L strand. One extra nucleotide'C'is present at the position 174 of MT-ND3 gene of A. fasciata, which is not observed at that of B. lagopus. Six conserved sequence boxes in the Domain II, named boxes F, E, D, C, CSBa, and CSBb, respectively, were recognized in the CRs of A. fasciata and B. lagopus. Rates and patterns of mitochondrial gene evolution within Accipitridae were also estimated. The highest dN/dS was detected for the MT-ATP8 gene (0.32493) among Accipitridae, while the lowest for the MT-CO1 gene (0.01415). Mitophylogenetic analysis supported the robust monophyly of Accipitriformes, and Cathartidae was basal to the balance of the order. Moreover, we performed phylogenetic analyses using two other data sets (two mitochondrial loci, and combined nuclear and mitochondrial loci). Our results indicate that the subfamily Aquilinae and all currently polytypic genera of this subfamily are monophyletic. These two novel mtDNA data will be useful in refining the phylogenetic relationships and evolutionary processes of Accipitriformes.

  2. MULTISCALE DOCUMENTATION AND MONITORING OF L’AQUILA HISTORICAL CENTRE USING UAV PHOTOGRAMMETRY

    Directory of Open Access Journals (Sweden)

    D. Dominici

    2017-05-01

    Full Text Available Nowadays geomatic techniques can guarantee not only a precise and accurate survey for the documentation of our historical heritage but also a solution to monitor its behaviour over time after, for example, a catastrophic event (earthquakes, landslides, ecc. Europe is trying to move towards harmonized actions to store information on cultural heritage (MIBAC with the ICCS forms, English heritage with the MIDAS scheme, etc but it would be important to provide standardized methods in order to perform measuring operations to collect certified metric data. The final result could be a database to support the entire management of the cultural heritage and also a checklist of “what to do” and “when to do it”. The wide range of geomatic techniques provides many solutions to acquire, to organize and to manage data at a multiscale level: high resolution satellite images can provide information in a short time during the “early emergency” while UAV photogrammetry and laser scanning can provide digital high resolution 3D models of buildings, ortophotos of roofs and facades and so on. This paper presents some multiscale survey case studies using UAV photogrammetry: from a minor historical village (Aielli to the centre of L’Aquila (Santa Maria di Collemaggio Church from the post-emergency to now. This choice has been taken not only to present how geomatics is an effective science for modelling but also to present a complete and reliable way to perform conservation and/or restoration through precise monitoring techniques, as shown in the third case study.

  3. The Virtual Monte Carlo

    CERN Document Server

    Hrivnacova, I; Berejnov, V V; Brun, R; Carminati, F; Fassò, A; Futo, E; Gheata, A; Caballero, I G; Morsch, Andreas

    2003-01-01

    The concept of Virtual Monte Carlo (VMC) has been developed by the ALICE Software Project to allow different Monte Carlo simulation programs to run without changing the user code, such as the geometry definition, the detector response simulation or input and output formats. Recently, the VMC classes have been integrated into the ROOT framework, and the other relevant packages have been separated from the AliRoot framework and can be used individually by any other HEP project. The general concept of the VMC and its set of base classes provided in ROOT will be presented. Existing implementations for Geant3, Geant4 and FLUKA and simple examples of usage will be described.

  4. Detecting earthquake damage in urban area: application to COSMO-SkyMed imagery of L'Aquila earthquake

    Science.gov (United States)

    Anniballe, R.; Chini, M.; Pierdicca, N.; Bignami, C.; Stramondo, S.; Noto, F.; Scalia, T.; Martinelli, A.; Mannella, A.

    2015-10-01

    Due to the improved spatial resolution, Earth observation (EO) data, either from Synthetic Aperture Radar (SAR) or optical sensor, provide the opportunity to assess earthquake damage of individual buildings. However, the operational use of EO data for earthquake damage mapping is basically limited to the visual inspection of Very High Resolution (VHR) optical imagery. In this work we investigate the feasibility of a damage assessment product at single building scale from a pair of VHR SAR images acquired before and after a seismic event. We perform the change analysis using the Kullbach-Leibler divergence and the intensity ratio and then we associate detected changes to a building map provided as GIS layer. Finally the expected SAR signature of a collapsed building is considered to identify severely damaged buildings. In order to test the proposed methodology we use Spotlight COSMO-SkyMed SAR imagery of L'Aquila (Italy) collected before and after the earthquake occurred on April 6, 2009. A macroseismic survey on the whole central area of L'Aquila city based on the European Macroseismic Scale 1998 is used to assess the capability of VHR SAR images to map damage.

  5. PTSD Growth and Substance Abuse Among a College Student Community: Coping Strategies after 2009 L'aquila Earthquake.

    Science.gov (United States)

    Bianchini, V; Roncone, R; Giusti, L; Casacchia, M; Cifone, M G; Pollice, R

    2015-01-01

    Aim of the study was the assessment of coping strategies, specifically substance use and post-traumatic growth (PTG), in 411 college students two years after 2009 L'Aquila earthquake. Post-Traumatic Growth Inventory (PTGI) was used to assess PTG and one question about substance use (alcohol, tobacco, cannabis) was asked to verify if students had modified their use in the post-earthquake compared with the pre-earthquake period. The 77.1% of college students were exposed to L'Aquila earthquake. The PTGI mean score was 35.23, underlining low positive coping strategies among student community. About substance abuse, the 43.8% of college students reported a marked increase in alcohol use, 7.8% in cannabis and the 15.8% reported an increase in nicotine use in the post-earthquake period. Despite these data, 12.5 % of the students reported a decrease in alcohol use after the earthquake and 17.3% of the sample reported a PTG, showing positive behaviors and attitudes after the traumatic experience of the natural disaster (increase of social relationships, appreciation of new future possibilities, and development of a new deep meaning of life). Inferential analysis shows a strong negative correlation between direct earthquake exposure and PTGI total score. In post-disaster settings, a systematic framework of case identification, triage, and mental health interventions, including the improvement of positive coping strategies, like the PTG, should be integrated into emergency medicine and trauma care responses.

  6. OXA-23 carbapenemase in multidrug-resistant Acinetobacter baumannii ST2 type: first identification in L'Aquila Hospital (Italy).

    Science.gov (United States)

    Perilli, Mariagrazia; Sabatini, Alessia; Pontieri, Eugenio; Celenza, Giuseppe; Segatore, Bernardetta; Bottoni, Carlo; Bellio, Pierangelo; Mancini, Alisia; Marcoccia, Francesca; Brisdelli, Fabrizia; Amicosante, Gianfranco

    2015-02-01

    In this study 114 extensively drug-resistant Acinetobacter baumannii clinical isolates were characterized. The strains were collected at L'Aquila Hospital after the earthquake in L'Aquila city (central Italy) on the 6th of April 2009. The genes blaOXA-23 and blaOXA-51 were detected in all clinical isolates analyzed, whereas blaTEM-1 allele was detected in 56/114 isolates. The blaOXA-23 gene is located downstream the ISAba region and is under control of a strong promoter. On 42/80 A. baumannii the presence of two class 1 integrons was ascertained on chromosomal DNA. Variable regions show different gene array: (1) aadB and aadA2, (2) aacA4, aac(6')-Ib-cr, and aadA1. Macrorestriction analysis using ApaI restriction endonuclease identifies three clusters (A, B, and C) according to pulsed-field gel electrophoresis profiles. All isolates analyzed belong to the clone A. baumannii sequence type 2.

  7. [Resilience, social relations, and pedagogic intervention five years after the earthquake occurred in L'Aquila (Central Italy) in 2009: an action-research in the primary schools].

    Science.gov (United States)

    Vaccarelli, Alessandro; Ciccozzi, Chiara; Fiorenza, Arianna

    2016-01-01

    the action-research "Outdoor training and citizenship between children from L'Aquila", carried out from 2014 to 2015 in some schools situated in the municipality of L'Aquila, aimed to answer to the needs emerged in reference to the social and psychological problems among children during the period after the L'Aquila earthquake occurred in 2009. In particular, the article provides documentary evidence about the results regarding the parts related to the study of resilience (cognitive objective) and of social relations (objective tied to the educational intervention), five years after the earthquake. the pedagogical research team, in close cooperation with the Cartography Laboratory of the University of L'Aquila and with the Grupo de Innovación Educativa Areté de la Universidad Politécnica de Madrid, has worked according to the research-action methodology, collecting secondary data and useful data to check the effectiveness of the educational actions put in place in order to promote resilient behaviours and to activate positive group dynamics. the study has been developed in 4 primary schools of the L'Aquila and has involved 83 children from 8 to 12 years. A control group made by 55 subjects, homogeneous for sex and age, has been identified in the primary schools of Borgorose, a little town near Rieti (Central Italy). data about the abilities of resilience and about the response to the stress have been collected in the first phase of the study with the purpose to outline the initial situation and develop an appropriate educational intervention. The comparison with the control group made by 55 subjects who were not from L'Aquila allowed to check that, 5 years after the disaster, the context of life produces a meaningful discrepancy in terms of responses to the stress and to the ability of resilience, and this fact is definitely negative for children from L'Aquila. On the other hand, data related to social relations allowed to verify how the educational intervention

  8. Investigating the architecture of the Paganica Fault (2009 Mw 6.1 earthquake, central Italy) by integrating high-resolution multiscale refraction tomography and detailed geological mapping

    Science.gov (United States)

    Villani, F.; Improta, L.; Pucci, S.; Civico, R.; Bruno, P. P. G.; Pantosti, D.

    2017-01-01

    We present a 2-D subsurface image of the Paganica Fault from a high-resolution refraction tomography and detailed geological investigation carried out across part of the northwestern segment of the 20-km-long Paganica-San Demetrio fault-system, and which was responsible of the 2009 April 6 Mw 6.1 L'Aquila earthquake (central Italy). We acquired two seismic profiles crossing the Paganica basin with a dense-wide aperture configuration. More than 30 000 P wave first-arrival traveltimes were input to a non-linear tomographic inversion. The obtained 250-300 m deep 2-D Vp images illuminate the shallow portion of the Paganica Fault, and depict additional unreported splays defining a complex half-graben structure. We interpret local thickening of low-Vp (tectonic clastic wedges above a high-Vp (3800-5000 m s-1) carbonate basement. These results are condensed in a 4.2-km-long section across the Paganica basin, clearly indicating that the Paganica Fault is a mature normal fault cutting the whole upper ˜10 km of the crust. We evaluate a minimum cumulative net displacement of 650 ± 90 m and a total heave of 530 ± 65 m accomplished by the Paganica Fault, respectively. In the conservative hypothesis that the extension started during the Gelasian (1.80-2.59 Ma), we obtain a minimum long-term slip-rate of 0.30 ± 0.07 mm yr-1 and an extension-rate of 0.25 ± 0.06 mm yr-1, respectively. Considering the regional averaged extensional field of ˜1 mm yr-1 obtained from geodetic and geological analyses at 104 yr timescale, we infer that the Paganica Fault accounts for ˜20 per cent of the NE-extension affecting this zone of the central Apennines axis due to the concurrent activity of other parallel normal fault-systems nearby (e.g. the Liri, Velino-Magnola, L'Aquila-Celano and Gran Sasso fault-systems).

  9. Fault-tolerant design

    CERN Document Server

    Dubrova, Elena

    2013-01-01

    This textbook serves as an introduction to fault-tolerance, intended for upper-division undergraduate students, graduate-level students and practicing engineers in need of an overview of the field.  Readers will develop skills in modeling and evaluating fault-tolerant architectures in terms of reliability, availability and safety.  They will gain a thorough understanding of fault tolerant computers, including both the theory of how to design and evaluate them and the practical knowledge of achieving fault-tolerance in electronic, communication and software systems.  Coverage includes fault-tolerance techniques through hardware, software, information and time redundancy.  The content is designed to be highly accessible, including numerous examples and exercises.  Solutions and powerpoint slides are available for instructors.   ·         Provides textbook coverage of the fundamental concepts of fault-tolerance; ·         Describes a variety of basic techniques for achieving fault-toleran...

  10. Fault Monitoring and Fault Recovery Control for Position Moored Tanker

    DEFF Research Database (Denmark)

    Fang, Shaoji; Blanke, Mogens

    2011-01-01

    This paper addresses fault tolerant control for position mooring of a shuttle tanker operating in the North Sea. A complete framework for fault diagnosis is presented but the loss of a sub-sea mooring line buoyancy element is given particular attention, since this fault could lead to mooring line....... Properties of detection and fault-tolerant control are demonstrated by high fidelity simulations....

  11. Fault tolerant control for uncertain systems with parametric faults

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2006-01-01

    A fault tolerant control (FTC) architecture based on active fault diagnosis (AFD) and the YJBK (Youla, Jarb, Bongiorno and Kucera)parameterization is applied in this paper. Based on the FTC architecture, fault tolerant control of uncertain systems with slowly varying parametric faults...

  12. Fault isolability conditions for linear systems with additive faults

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob

    2006-01-01

    In this paper, we shall show that an unlimited number of additive single faults can be isolated under mild conditions if a general isolation scheme is applied. Multiple faults are also covered. The approach is algebraic and is based on a set representation of faults, where all faults within a set...

  13. Fault Analysis in Cryptography

    CERN Document Server

    Joye, Marc

    2012-01-01

    In the 1970s researchers noticed that radioactive particles produced by elements naturally present in packaging material could cause bits to flip in sensitive areas of electronic chips. Research into the effect of cosmic rays on semiconductors, an area of particular interest in the aerospace industry, led to methods of hardening electronic devices designed for harsh environments. Ultimately various mechanisms for fault creation and propagation were discovered, and in particular it was noted that many cryptographic algorithms succumb to so-called fault attacks. Preventing fault attacks without

  14. The L'Aquila process and the perils of bad communication of science

    Science.gov (United States)

    Alberti, Antonio

    2013-04-01

    Responsibilities and observance of ethical behaviour by scientists have increased more than ever with the advancement of science and of the social and economic development of a country. Nowadays, geoscientists are often charged by local and/or national and international authorities with the task of providing ways to foster economic development while protecting human life and safeguarding the environment. But besides technical and scientific expertise, in a democratic country all this requires efficient ways and various channels of scientific divulgation. Geoscientists themselves should be involved in these procedures, or at least they should be called to verify that correct communication is actually released. Unfortunately, it seems that awareness of such new and ever-increasing responsibilities is not yet being always realized at a needed level. The question is especially sensible in Italy, a country in which the hydro-geological, seismological, volcanological and coastal set-up requires careful technical and scientific treatment. Given the fragility of the natural system, the role of geoscientists should not be restricted to the delivery of scientific expertise: in fact, and perhaps more than elsewhere, problems are compounded by the need of communication based on sound science not only to governing authorities, but also to the public at large, possibly including also an array of mass media. Many international organizations have been wrongly interpreting the accusation and especially the sentence at the first stage of the L'Aquila process as a problem of impossibility to predict earthquakes. But the recently published motivation of the sentence seems to have brought to light the lack of a scrupulous overview of the situation prior to the disastrous seismic event, practically leaving the task of public information to the judgment or perception of the national agency in charge of natural hazards. It turned out that a major outcome of the process, apart from the

  15. Mise en évidence de déformations en faille inverse avec ruptures de surface cosismiques dans des dépôts colluviaux würmiens du versant nord du mont Ventoux (Provence occidentale, France)Evidence of reverse faulting and coseismic surface ruptures in Würm colluvial deposits from the Mt Ventoux northern slope (Western Provence, France)

    Science.gov (United States)

    Dutour, Alain; Philip, Hervé; Jaurand, Erwan; Combes, Philippe

    In western Provence (France), brittle deformation of Quaternary age occurring in the vicinity of the Nı̂mes and Durance faults has been linked to palaeoseisms of significant magnitude. Our new observations made on the southern rim of the Tertiary Malaucène Basin, in the continuation of a thrust to the north of Mt Ventoux, present evidence for reverse faulting deformation in deposits of a Würm colluvial fan. The analysis of a trench section provides clear evidence for: (1) the development of two successive surface ruptures and degradation of associated scarps during the Mid-Upper Würm, and, (2) the continuation of the reverse fault within the Oligocene basement. These tectonic events were associated with earthquakes of at least 6 in magnitude. To cite this article: A. Dutour et al., C. R. Geoscience 334 (2002) 849-856.

  16. Monte Carlo Option Princing

    Directory of Open Access Journals (Sweden)

    Cecilia Maya

    2004-12-01

    Full Text Available El método Monte Carlo se aplica a varios casos de valoración de opciones financieras. El método genera una buena aproximación al comparar su precisión con la de otros métodos numéricos. La estimación que produce la versión Cruda de Monte Carlo puede ser aún más exacta si se recurre a metodologías de reducción de la varianza entre las cuales se sugieren la variable antitética y de la variable de control. Sin embargo, dichas metodologías requieren un esfuerzo computacional mayor por lo cual las mismas deben ser evaluadas en términos no sólo de su precisión sino también de su eficiencia.

  17. Monte Carlo and nonlinearities

    CERN Document Server

    Dauchet, Jérémi; Blanco, Stéphane; Caliot, Cyril; Charon, Julien; Coustet, Christophe; Hafi, Mouna El; Eymet, Vincent; Farges, Olivier; Forest, Vincent; Fournier, Richard; Galtier, Mathieu; Gautrais, Jacques; Khuong, Anaïs; Pelissier, Lionel; Piaud, Benjamin; Roger, Maxime; Terrée, Guillaume; Weitz, Sebastian

    2016-01-01

    The Monte Carlo method is widely used to numerically predict systems behaviour. However, its powerful incremental design assumes a strong premise which has severely limited application so far: the estimation process must combine linearly over dimensions. Here we show that this premise can be alleviated by projecting nonlinearities on a polynomial basis and increasing the configuration-space dimension. Considering phytoplankton growth in light-limited environments, radiative transfer in planetary atmospheres, electromagnetic scattering by particles and concentrated-solar-power-plant productions, we prove the real world usability of this advance on four test-cases that were so far regarded as impracticable by Monte Carlo approaches. We also illustrate an outstanding feature of our method when applied to sharp problems with interacting particles: handling rare events is now straightforward. Overall, our extension preserves the features that made the method popular: addressing nonlinearities does not compromise o...

  18. FiSH: put fault data in a seismic hazard basket

    Science.gov (United States)

    Pace, Bruno; Visini, Francesco; Peruzza, Laura

    2016-04-01

    The practice of using fault sources in seismic hazard studies is growing in popularity, including in regions with moderate seismic activity, such as the European countries. In these areas, fault identification may be affected by similarly large uncertainties in the historical and instrumental seismic histories of more active areas that have not been inhabited for long periods of time. Certain studies have effectively applied a time-dependent perspective to combine historical and instrumental seismic data with geological and paleoseismological information, partially compensating for a lack of information. We present a package of Matlab® tools (called FiSH), in publication on Seismological Research Letters, designed to help seismic hazard modellers analyse fault data. These tools enable the derivation of expected earthquake rates given common fault data, and allow you to test the consistency between the magnitude frequency distributions assigned to a fault and some available observations. The basic assumption of FiSH is that the geometric and kinematic features of a fault are the expression of its seismogenic potential. Three tools have been designed to integrate the variable levels of information available: (a) the first tool allows users to convert fault geometry and slip rates into a global budget of the seismic moment released in a given time frame, taking uncertainties into account; (b) the second tool computes the recurrence parameters and associated uncertainties from historical and/or paleoseismological data; 
(c) the third tool outputs time-independent or time-dependent earthquake rates for different magnitude frequency distribution models. We present moreover a test case to illustrate the capabilities of FiSH, on the Paganica normal fault in Central Italy that ruptured during the L'Aquila 2009 earthquake sequence (mainshock Mw 6.3). FiSH is available at http://fish-code.com, and the source codes are open. We encourage users to handle the scripts

  19. Fundamentals of Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Wollaber, Allan Benton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-16

    This is a powerpoint presentation which serves as lecture material for the Parallel Computing summer school. It goes over the fundamentals of the Monte Carlo calculation method. The material is presented according to the following outline: Introduction (background, a simple example: estimating π), Why does this even work? (The Law of Large Numbers, The Central Limit Theorem), How to sample (inverse transform sampling, rejection), and An example from particle transport.

  20. Quaternary Fault Lines

    Data.gov (United States)

    Department of Homeland Security — This data set contains locations and information on faults and associated folds in the United States that are believed to be sources of M>6 earthquakes during the...

  1. Pulsed strain release on the Altyn Tagh fault, northwest China

    Science.gov (United States)

    Gold, Ryan D.; Cowgill, Eric; Arrowsmith, J. Ramón; Friedrich, Anke M.

    2017-02-01

    Earthquake recurrence models assume that major surface-rupturing earthquakes are followed by periods of reduced rupture probability as stress rebuilds. Although purely periodic, time- or slip-predictable rupture models are known to be oversimplifications, a paucity of long records of fault slip clouds understanding of fault behavior and earthquake recurrence over multiple ruptures. Here, we report a 16 kyr history of fault slip-including a pulse of accelerated slip from 6.4 to 6.0 ka-determined using a Monte Carlo analysis of well-dated offset landforms along the central Altyn Tagh strike-slip fault (ATF) in northwest China. This pulse punctuates a median rate of 8.1+1.2/-0.9 mm /a and likely resulted from either a flurry of temporally clustered ∼Mw 7.5 ground-rupturing earthquakes or a single large >Mw 8.2 earthquake. The clustered earthquake scenario implies rapid re-rupture of a fault reach >195 km long and indicates decoupled rates of elastic strain energy accumulation versus dissipation, conceptualized as a crustal stress battery. If the pulse reflects a single event, slip-magnitude scaling implies that it ruptured much of the ATF with slip similar to, or exceeding, the largest documented historical ruptures. Both scenarios indicate fault rupture behavior that deviates from classic time- or slip-predictable models.

  2. Pulsed strain release on the Altyn Tagh fault, northwest China

    Science.gov (United States)

    Gold, Ryan D.; Cowgill, Eric; Arrowsmith, J. Ramón; Friedrich, Anke M.

    2017-01-01

    Earthquake recurrence models assume that major surface-rupturing earthquakes are followed by periods of reduced rupture probability as stress rebuilds. Although purely periodic, time- or slip-predictable rupture models are known to be oversimplifications, a paucity of long records of fault slip clouds understanding of fault behavior and earthquake recurrence over multiple ruptures. Here, we report a 16 kyr history of fault slip—including a pulse of accelerated slip from 6.4 to 6.0 ka—determined using a Monte Carlo analysis of well-dated offset landforms along the central Altyn Tagh strike-slip fault (ATF) in northwest China. This pulse punctuates a median rate of 8.1+1.2/−0.9 mm/a and likely resulted from either a flurry of temporally clustered ∼Mw 7.5 ground-rupturing earthquakes or a single large >Mw 8.2 earthquake. The clustered earthquake scenario implies rapid re-rupture of a fault reach >195 km long and indicates decoupled rates of elastic strain energy accumulation versus dissipation, conceptualized as a crustal stress battery. If the pulse reflects a single event, slip-magnitude scaling implies that it ruptured much of the ATF with slip similar to, or exceeding, the largest documented historical ruptures. Both scenarios indicate fault rupture behavior that deviates from classic time- or slip-predictable models.

  3. Characterization of earthquake-induced ground motion from the L'Aquila seismic sequence of 2009, Italy

    Science.gov (United States)

    Malagnini, Luca; Akinci, Aybige; Mayeda, Kevin; Munafo', Irene; Herrmann, Robert B.; Mercuri, Alessia

    2011-01-01

    Based only on weak-motion data, we carried out a combined study on region-specific source scaling and crustal attenuation in the Central Apennines (Italy). Our goal was to obtain a reappraisal of the existing predictive relationships for the ground motion, and to test them against the strong-motion data [peak ground acceleration (PGA), peak ground velocity (PGV) and spectral acceleration (SA)] gathered during the Mw 6.15 L'Aquila earthquake (2009 April 6, 01:32 UTC). The L'Aquila main shock was not part of the predictive study, and the validation test was an extrapolation to one magnitude unit above the largest earthquake of the calibration data set. The regional attenuation was determined through a set of regressions on a data set of 12 777 high-quality, high-gain waveforms with excellent S/N ratios (4259 vertical and 8518 horizontal time histories). Seismograms were selected from the recordings of 170 foreshocks and aftershocks of the sequence (the complete set of all earthquakes with ML≥ 3.0, from 2008 October 1 to 2010 May 10). All waveforms were downloaded from the ISIDe web page (), a web site maintained by the Istituto Nazionale di Geofisica e Vulcanologia (INGV). Weak-motion data were used to obtain a moment tensor solution, as well as a coda-based moment-rate source spectrum, for each one of the 170 events of the L'Aquila sequence (2.8 ≤Mw≤ 6.15). Source spectra were used to verify the good agreement with the source scaling of the Colfiorito seismic sequence of 1997-1998 recently described by Malagnini (2008). Finally, results on source excitation and crustal attenuation were used to produce the absolute site terms for the 23 stations located within ˜80 km of the epicentral area. The complete set of spectral corrections (crustal attenuation and absolute site effects) was used to implement a fast and accurate tool for the automatic computation of moment magnitudes in the Central Apennines.

  4. Active Fault Isolation in MIMO Systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2014-01-01

    Active fault isolation of parametric faults in closed-loop MIMO system s are considered in this paper. The fault isolation consists of two steps. T he first step is group- wise fault isolation. Here, a group of faults is isolated from other pos sible faults in the system. The group-wise fault iso...

  5. 利用PSInSAR时间序列研究拉奎拉地震位移场变化特征%Displacement field characteristics on L'Aquila earthquake from PSInSAR time series

    Institute of Scientific and Technical Information of China (English)

    罗三明; 杨国华; 董运洪; 李陶; 袁油新; 贾有良

    2012-01-01

    Using 9 SLC Envisat ASAR images, time series of differential interferograms and consequent co-seismic deformation field of the L'Aquila earthquake (Mw6. 3 on 6 April 2009) are obtained by PSInSAR method. Furthermore, deformation processes of rupture zone are numerically analyzed by using Delaunay triangulation algorithms based on above results. The results showed that: 1) Envisat ASAR detected clearly the process of displacement field with time variation and the different deformation characteristics associated with source rupture: creep displacement before the earthquake-obvious deformation-rapidly change during the shocking-continuous deformating of significantly slowing down after shocking. 2) In area covered about 54 × 59 km2, westward of epicenter shows uplift with maximum capacity of 130 mm in the LOS, and east of epicenter was subsidence region, But the head settlement capacity was in rupture zone, and its majority formed in the course of shocking and subsequence. The maximum settlement reached 210 mm in LOS, consisting with GPS measurements. 3)Tthe strongest deformation and surface faulting within zone about 22 × 14 km2, with an orientation of 135°, occurred along the NW striking and SW dipping Paganica-S. Demetrio normal fault; 4) The works from this paper have provided a comprehensive case for digging methods for earthquake forecasting with time series PSInSAR.%对2009年4月6日意大利拉奎拉(L’Aquila) Mw6.3级地震9景ENVISAT重轨单视复数据采用双轨模式进行永久散射体(Persistent Scatterer,PS)处理,获得了此次地震时序位移场,结合PS位移场Delaunay算法数值分析,结果表明:1)Envisat干涉雷达完整而清晰地探测到了地震前后位移场变化过程及其在不同阶段与震源断裂相关的不同形变特征:震前蠕动位移-明显变形-震期快速突变-震后量级明显减缓的持续变形;2)在此次分析的约54×59 km2区域内,震中以西为大面积上升区,

  6. Rough Faults, Distributed Weakening, and Off-Fault Deformation

    Science.gov (United States)

    Griffith, W. A.; Nielsen, S. B.; di Toro, G.; Smith, S. A.; Niemeijer, A. R.

    2009-12-01

    We report systematic spatial variations of fault rocks along non-planar strike-slip faults cross-cutting the Lake Edison Granodiorite, Sierra Nevada, California (Sierran Wavy Fault) and the Lobbia outcrops of the Adamello Batholith in the Italian Alps (Lobbia Wavy Fault). In the case of the Sierran fault, pseudotachylyte formed at contractional fault bends, where it is found as thin (1-2 mm) fault-parallel veins. Epidote and chlorite developed in the same seismic context as the pseudotachylyte and are especially abundant in extensional fault bends. We argue that the presence of fluids, as illustrated by this example, does not necessarily preclude the development of frictional melt. In the case of the Lobbia fault, pseudotachylyte is present in variable thickness along the length of the fault, but the pseudotachylyte veins thicken and pool in extensional bends. The Lobbia fault surface is self-affine, and we conduct a quantitative analysis of microcrack distribution, stress, and friction along the fault. Numerical modeling results show that opening in extensional bends and localized thermal weakening in contractional bends counteract resistance encountered by fault waviness, resulting in an overall weaker fault than suggested by the corresponding static friction coefficient. Models also predict stress redistribution around bends in the faults which mirror microcrack distributions, indicating significant elastic and anelastic strain energy is dissipated into the wall rocks due to non-planar fault geometry. Together these observations suggest that, along non-planar faults, damage and energy dissipation occurs along the entire fault during slip, rather than being confined to the region close to the crack tip as predicted by classical fracture mechanics.

  7. The environmental project of the enhancement of the fluvial area: L’Aquila and the Aterno River

    Directory of Open Access Journals (Sweden)

    Luciana Mastrolonardo

    2016-06-01

    Full Text Available Il contributo si colloca in un programma interdisciplinare volto alla valorizzazione e la tutela del fiume, attraverso il controllo dei flussi e l’attivazione di simbiosi. Si integrano, con un approccio che parte dalla progettazione ambientale, le tematiche urbane, paesaggistiche, tecnologiche ed ecologiche, per orientare lo sviluppo del territorio in termini di tutela e valorizzazione delle risorse, e per recuperare le discontinuità rappresentata oggi dal fiume, in alcuni contesti urbani, conferendole maggiore riconoscibilità e potenzialità. Nello specifico si indaga il rapporto tra L’Aquila e il fiume Aterno per individuare, a livello locale, le strategie perseguibili per il recupero delle connessioni tra l’ambito fluviale e urbano, per la valorizzazione del territorio e il ripristino della funzionalità dell’acqua nel suo ciclo vitale. 

  8. 福建省发现白化白腹山鵰%Albinic Aquila fasciata fasciata discovered in Fujian Province

    Institute of Scientific and Technical Information of China (English)

    唐庆圆; 唐兆和

    2004-01-01

    白腹山鵰(Aquila fasciata fasciata)属于隼形目鹰科,是国家重点珍稀二级保护鸟类之一,国内主要分布于福建、广东、广西,西至云南和贵州,国外见于欧洲南部、非洲北部、印度等地。2001年12月9日我们从闽侯县白沙镇一佗农民处获得此白化鹏类,据了解这只鵰是从电线杆上摔下致死的,

  9. Biotelemetery data for golden eagles (Aquila chrysaetos) captured in coastal southern California, February 2016–February 2017

    Science.gov (United States)

    Tracey, Jeff A.; Madden, Melanie C.; Sebes, Jeremy B.; Bloom, Peter H.; Katzner, Todd E.; Fisher, Robert N.

    2017-05-12

    Because of a lack of clarity about the status of golden eagles (Aquila chrysaetos) in coastal southern California, the USGS, in collaboration with local, State, and other Federal agencies, began a multi-year survey and tracking program of golden eagles to address questions regarding habitat use, movement behavior, nest occupancy, genetic population structure, and human impacts on eagles. Golden eagle trapping and tracking efforts began in September 2014. During trapping efforts from September 29, 2014, to February 23, 2016, 27 golden eagles were captured. During trapping efforts from February 24, 2016, to February 23, 2017, an additional 10 golden eagles (7 females and 3 males) were captured in San Diego, Orange, and western Riverside Counties. Biotelemetry data for 26 of the 37 golden eagles that were transmitting data from February 24, 2016, to February 23, 2017 are presented. These eagles ranged as far north as northern Nevada and southern Wyoming, and as far south as La Paz, Baja California, Mexico.

  10. The self-built ecovillage in L'Aquila, Italy: community resilience as a grassroots response to environmental shock.

    Science.gov (United States)

    Fois, Francesca; Forino, Giuseppe

    2014-10-01

    The paper applies the community resilience approach to the post-disaster case of Pescomaggiore, an Italian village affected by the L'Aquila earthquake in 2009. A group of residents refused to accept the housing recovery solutions proposed by the government, opting for autonomous recovery. They developed a housing project in the form of a self-built ecovillage, characterised by earthquake-proof buildings made of straw and wood. The project is a paradigmatic example of a community-based response to an external shock. It illustrates the concept of 'community resilience', which is widely explored in the scientific debate but still vaguely defined. Based on qualitative methodologies, the paper seeks to understand how the community resilience process can be enacted in alternative social practices such as ecovillages. The goal is to see under which conditions natural disasters can be considered windows of opportunity for sustainability.

  11. Short-term earthquake forecasting experiment before and during the L’Aquila (central Italy seismic sequence of April 2009

    Directory of Open Access Journals (Sweden)

    Maura Murru

    2015-03-01

    Full Text Available In this paper, we compare the forecasting performance of several statistical models, which are used to describe the occurrence process of earthquakes in forecasting the short-term earthquake probabilities during the L’Aquila earthquake sequence in central Italy in 2009. These models include the Proximity to Past Earthquakes (PPE model and two versions of the Epidemic Type Aftershock Sequence (ETAS model. We used the information gains corresponding to the Poisson and binomial scores to evaluate the performance of these models. It is shown that both ETAS models work better than the PPE model. However, in comparing the two types of ETAS models, the one with the same fixed exponent coefficient (alpha = 2.3 for both the productivity function and the scaling factor in the spatial response function (ETAS I, performs better in forecasting the active aftershock sequence than the model with different exponent coefficients (ETAS II, when the Poisson score is adopted. ETAS II performs better when a lower magnitude threshold of 2.0 and the binomial score are used. The reason is found to be that the catalog does not have an event of similar magnitude to the L’Aquila mainshock (Mw 6.3 in the training period (April 16, 2005 to March 15, 2009, and the (alpha-value is underestimated, thus the forecast seismicity is underestimated when the productivity function is extrapolated to high magnitudes. We also investigate the effect of the inclusion of small events in forecasting larger events. These results suggest that the training catalog used for estimating the model parameters should include earthquakes of magnitudes similar to the mainshock when forecasting seismicity during an aftershock sequence.

  12. S.S. Annunziata Church (L'Aquila, Italy) unveiled by non- and micro-destructive testing techniques

    Science.gov (United States)

    Sfarra, Stefano; Cheilakou, Eleni; Theodorakeas, Panagiotis; Paoletti, Domenica; Koui, Maria

    2017-03-01

    The present research work explores the potential of an integrated inspection methodology, combining Non-destructive testing and micro-destructive analytical techniques, for both the structural assessment of the S.S. Annunziata Church located in Roio Colle (L'Aquila, Italy) and the characterization of its wall paintings' pigments. The study started by applying passive thermal imaging for the structural monitoring of the church before and after the application of a consolidation treatment, while active thermal imaging was further used for assessing this consolidation procedure. After the earthquake of 2009, which seriously damaged the city of L'Aquila and its surroundings, part of the internal plaster fell off revealing the presence of an ancient mural painting that was subsequently investigated by means of a combined analytical approach involving portable VIS-NIR fiber optics diffuse reflectance spectroscopy (FORS) and laboratory methods, such as environmental scanning electron microscopy (ESEM) coupled with energy dispersive X-ray analysis (EDX), and attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR). The results obtained from the thermographic analysis provided information concerning the two different constrictive phases of the Church, enabled the assessment of the consolidation treatment, and contributed to the detection of localized problems mainly related to the rising damp phenomenon and to biological attack. In addition, the results obtained from the combined analytical approach allowed the identification of the wall painting pigments (red and yellow ochre, green earth, and smalt) and provided information on the binding media and the painting technique possibly applied by the artist. From the results of the present study, it is possible to conclude that the joint use of the above stated methods into an integrated methodology can produce the complete set of useful information required for the planning of the Church's restoration

  13. Limits on the potential accuracy of earthquake risk evaluations using the L’Aquila (Italy earthquake as an example

    Directory of Open Access Journals (Sweden)

    John Douglas

    2015-06-01

    Full Text Available This article is concerned with attempting to ‘predict’ (hindcast the damage caused by the L’Aquila 2009 earthquake (Mw 6.3 and, more generally, with the question of how close predicted damage can ever be to observations. Damage is hindcast using a well-established empirical-based approach based on vulnerability indices and macroseismic intensities, adjusted for local site effects. Using information that was available before the earthquake and assuming the same event characteristics as the L’Aquila mainshock, the overall damage is reasonably well predicted but there are considerable differences in the damage pattern. To understand the reasons for these differences, information that was only available after the event were include within the calculation. Despite some improvement in the predicted damage, in particularly by the modification of the vulnerability indices and the parameter influencing the width of the damage distribution, these hindcasts do not match all the details of the observations. This is because of local effects: both in terms of the ground shaking, which is only detectable by the installation of a much denser strong-motion network and a detailed microzonation, and in terms of the building vulnerability, which cannot be modeled using a statistical approach but would require detailed analytical modeling for which calibration data are likely to be lacking. Future studies should concentrate on adjusting the generic components of the approach to make them more applicable to their location of interest. To increase the number of observations available to make these adjustments, we encourage the collection of damage states (and not just habitability classes following earthquakes and also the installation of dense strong-motion networks in built-up areas.

  14. Monts Jura Jazz Festival

    CERN Multimedia

    2012-01-01

    The 5th edition of the "Monts Jura Jazz Festival" will take place at the Esplanade du Lac in Divonne-les-Bains, France on September 21 and 22. This festival organized by the CERN Jazz Club and supported by the CERN Staff Association is becoming a major musical event in the Geneva region. International Jazz artists like Didier Lockwood and David Reinhardt are part of this year outstanding program. Full program and e-tickets are available on the festival website. Don't miss this great festival!

  15. Monts Jura Jazz Festival

    CERN Multimedia

    Jazz Club

    2012-01-01

    The 5th edition of the "Monts Jura Jazz Festival" that will take place on September 21st and 22nd 2012 at the Esplanade du Lac in Divonne-les-Bains. This festival is organized by the "CERN Jazz Club" with the support of the "CERN Staff Association". This festival is a major musical event in the French/Swiss area and proposes a world class program with jazz artists such as D.Lockwood and D.Reinhardt. More information on http://www.jurajazz.com.

  16. LMC: Logarithmantic Monte Carlo

    Science.gov (United States)

    Mantz, Adam B.

    2017-06-01

    LMC is a Markov Chain Monte Carlo engine in Python that implements adaptive Metropolis-Hastings and slice sampling, as well as the affine-invariant method of Goodman & Weare, in a flexible framework. It can be used for simple problems, but the main use case is problems where expensive likelihood evaluations are provided by less flexible third-party software, which benefit from parallelization across many nodes at the sampling level. The parallel/adaptive methods use communication through MPI, or alternatively by writing/reading files, and mostly follow the approaches pioneered by CosmoMC (ascl:1106.025).

  17. Characterization of active fault scarps from medium to high resolution DEM: case studies from Central and Southern Apennines (Italy)

    Science.gov (United States)

    Brunori, C.; Cinti, F. R.; Ventura, G.

    2013-12-01

    We identify geo-morphometric features of active fault scarps in Italy through a semiautomatic processing using GIS. Medium to high resolution DEM was used to characterize the geometry, structural, and erosive elements of two seismogenic normal faults in Central and Southern Apennines. The Pettino fault in L'Aquila area was detected using a 1 m pixel DEM derived from airborne LiDAR survey (Friuli Venezia Giulia Civil Protection). For the Castrovillari fault in northern Calabria region was used a 4 m pixel DEM (Regional Cartography Office of Regione Calabria). Scarp segments are region of planar discontinuities identified by selected values of DEM-derived Terrain Ruggedness Index (TRI) and Vector Ruggedness Measure (VRM). These planar discontinuities corresponds to landscape features such as, river terraces, roads scarps, and other natural or human features. The discrimination between these features have been accomplished overlaying extracted features on aerial photograph, geological and geomorphologic maps and in situ survey. After that, we perform the quantitative and statistical analysis of these areas identified as "fault scarps". The identification of elements relative to the scarps (e.g. base, crest, slope) is then obtained to derive the estimate of parameters describing the fault: altitude, height of the scarp, length, slope and aspect, Terrain Ruggedness Index (TRI) and Vector Ruggedness Measure (VRM). The spatial distribution of the extracted values was obtained through their statistical analysis. We analyze scarp parameters variations along the whole scarp extent, such as strike value from aspect variations, slope and profile curvature differences as indicators of tectonic and/or erosion activity. The combined analysis of the DEM-derived parameters allows us to (a) define aspects of three-dimensional scarp geometry, (b) decipher its geomorphological significance, and (c) estimate the long-term slip rate.

  18. Directional Resonance and Wavefield Polarization in the Damage Zone of the Campo Imperatore Fault Zone (central Italy).

    Science.gov (United States)

    Pischiutta, M.; Fondriest, M.; Demurtas, M.; Di Toro, G.; Rovelli, A.

    2014-12-01

    To infer the occurrence of directional amplification effects, we performed ambient noise measurements along a 200m transect crossing the Campo Imperatore fault zone (Central Italy), an exhumed analogue of the faults responsible of the L'Aquila 2009 earthquake sequence, We have recently found in several fault zones that ambient noise is not randomly polarized, but it is amplified on the horizontal plane along a specific site-dependent direction. The analysis repeated using earthquake signals revealed that S-coda waves and surface waves show the same polarization direction, independently of the earthquake backazimuth and focal mechanism. We have explained the observed directional amplifications in terms of fractured rocks in the fault damage zone, polarization being oriented orthogonally to fractures produced by the kinematic stress component. Therefore ground motion directional amplification could be related to the higher compliance of fractured rocks. In the other studies the fracture pattern was derived from numerical-analytical modeling based on the fault geometry and kinematics, or compared with the fast direction of shear wave obtained by seismic anisotropy analysis. The aim of this study is to compare observations with fracture measurements (strike, dip, dip-azimuth, spacing, later continuity, etc.) performed in the selected fault zone. We thus acquired ambient noise using 25 stations installed along a transect where detailed structural geological measurements were carried out. Ambient noise was recorded for around 1 hour, and was processed to compute the horizontal-to-vertical noise spectral ratio as a function of frequency and direction of motion. Wavefield polarization was investigated in the time-frequency domain as well. We found that, in spite of the complexity of the seismic data, the observed polarization pattern is generally oriented orthogonal to the measured dominant fracture system, confirming the existence of a high angle relation between ground

  19. Fault Monitooring and Fault Recovery Control for Position Moored Tanker

    DEFF Research Database (Denmark)

    Fang, Shaoji; Blanke, Mogens

    2009-01-01

    This paper addresses fault tolerant control for position mooring of a shuttle tanker operating in the North Sea. A complete framework for fault diagnosis is presented but the loss of a sub-sea mooring line buoyancy element is given particular attention, since this fault could lead to line breakage...... algorithm is proposed to accommodate buoyancy element failure and keep the mooring system in a safe state. Detection properties and fault-tolerant control are demonstrated by high delity simulations...

  20. Discriminating Fault Rate and Persistency to Improve Fault Treatment

    OpenAIRE

    Bondavalli, Andrea; Chiaradonna, Silvano; Di Giandomenico,Felicita; Grandoni, Fabrizio

    1997-01-01

    In this paper the consolidate identification of faults, distinguished as transient or permanent/intermittent, is approached, through the definition of a fault identification mechanism, called a-count. The goal is to allow continued use of parts being hit by transient faults, which may lead to better overall system performance if proper handling is provided. Transient faults discrimination is especially important in all those dependability-qualified applications where replacing and repairing f...

  1. Study on Fault Current of DFIG during Slight Fault Condition

    OpenAIRE

    Xiangping Kong; Zhe Zhang; Xianggen Yin; Zhenxing Li

    2013-01-01

    In order to ensure the safety of DFIG when severe fault happens, crowbar protection is adopted. But during slight fault condition, the crowbar protection will not trip, and the DFIG is still excited by AC-DC-AC converter. In this condition, operation characteristics of the converter have large influence on the fault current characteristics of DFIG. By theoretical analysis and digital simulation, the fault current characteristics of DFIG during slight voltage dips are studied. And the influenc...

  2. Orion GN&C Fault Management System Verification: Scope And Methodology

    Science.gov (United States)

    Brown, Denise; Weiler, David; Flanary, Ronald

    2016-01-01

    In order to ensure long-term ability to meet mission goals and to provide for the safety of the public, ground personnel, and any crew members, nearly all spacecraft include a fault management (FM) system. For a manned vehicle such as Orion, the safety of the crew is of paramount importance. The goal of the Orion Guidance, Navigation and Control (GN&C) fault management system is to detect, isolate, and respond to faults before they can result in harm to the human crew or loss of the spacecraft. Verification of fault management/fault protection capability is challenging due to the large number of possible faults in a complex spacecraft, the inherent unpredictability of faults, the complexity of interactions among the various spacecraft components, and the inability to easily quantify human reactions to failure scenarios. The Orion GN&C Fault Detection, Isolation, and Recovery (FDIR) team has developed a methodology for bounding the scope of FM system verification while ensuring sufficient coverage of the failure space and providing high confidence that the fault management system meets all safety requirements. The methodology utilizes a swarm search algorithm to identify failure cases that can result in catastrophic loss of the crew or the vehicle and rare event sequential Monte Carlo to verify safety and FDIR performance requirements.

  3. Computer hardware fault administration

    Science.gov (United States)

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-09-14

    Computer hardware fault administration carried out in a parallel computer, where the parallel computer includes a plurality of compute nodes. The compute nodes are coupled for data communications by at least two independent data communications networks, where each data communications network includes data communications links connected to the compute nodes. Typical embodiments carry out hardware fault administration by identifying a location of a defective link in the first data communications network of the parallel computer and routing communications data around the defective link through the second data communications network of the parallel computer.

  4. Fault Tolerant Computer Architecture

    CERN Document Server

    Sorin, Daniel

    2009-01-01

    For many years, most computer architects have pursued one primary goal: performance. Architects have translated the ever-increasing abundance of ever-faster transistors provided by Moore's law into remarkable increases in performance. Recently, however, the bounty provided by Moore's law has been accompanied by several challenges that have arisen as devices have become smaller, including a decrease in dependability due to physical faults. In this book, we focus on the dependability challenge and the fault tolerance solutions that architects are developing to overcome it. The two main purposes

  5. Fault tolerant linear actuator

    Science.gov (United States)

    Tesar, Delbert

    2004-09-14

    In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.

  6. Fault tolerant control based on active fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2005-01-01

    An active fault diagnosis (AFD) method will be considered in this paper in connection with a Fault Tolerant Control (FTC) architecture based on the YJBK parameterization of all stabilizing controllers. The architecture consists of a fault diagnosis (FD) part and a controller reconfiguration (CR...

  7. Wind turbine fault detection and fault tolerant control

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Johnson, Kathryn

    2013-01-01

    In this updated edition of a previous wind turbine fault detection and fault tolerant control challenge, we present a more sophisticated wind turbine model and updated fault scenarios to enhance the realism of the challenge and therefore the value of the solutions. This paper describes the challe...

  8. Improving Multiple Fault Diagnosability using Possible Conflicts

    Data.gov (United States)

    National Aeronautics and Space Administration — Multiple fault diagnosis is a difficult problem for dynamic systems. Due to fault masking, compensation, and relative time of fault occurrence, multiple faults can...

  9. Fault Management Assistant (FMA) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — S&K Aerospace (SKA) proposes to develop the Fault Management Assistant (FMA) to aid project managers and fault management engineers in developing better and more...

  10. ESR dating of fault rocks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hee Kwon [Kangwon National Univ., Chuncheon (Korea, Republic of)

    2002-03-15

    Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then trow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs grain size shows a plateau for grains below critical size : these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected from the Yangsan fault system. ESR dates from the this fault system range from 870 to 240 ka. Results of this research suggest that long-term cyclic fault activity continued into the pleistocene.

  11. Seismic fault zone trapped noise

    National Research Council Canada - National Science Library

    Hillers, G; Campillo, M; Ben‐Zion, Y; Roux, P

    2014-01-01

    Systematic velocity contrasts across and within fault zones can lead to head and trapped waves that provide direct information on structural units that are important for many aspects of earthquake and fault mechanics...

  12. The property of fault zone and fault activity of Shionohira Fault, Fukushima, Japan

    Science.gov (United States)

    Seshimo, K.; Aoki, K.; Tanaka, Y.; Niwa, M.; Kametaka, M.; Sakai, T.; Tanaka, Y.

    2015-12-01

    The April 11, 2011 Fukushima-ken Hamadori Earthquake (hereafter the 4.11 earthquake) formed co-seismic surface ruptures trending in the NNW-SSE direction in Iwaki City, Fukushima Prefecture, which were newly named as the Shionohira Fault by Ishiyama et al. (2011). This earthquake was characterized by a westward dipping normal slip faulting, with a maximum displacement of about 2 m (e.g., Kurosawa et al., 2012). To the south of the area, the same trending lineaments were recognized to exist even though no surface ruptures occurred by the earthquake. In an attempt to elucidate the differences of active and non-active segments of the fault, this report discusses the results of observation of fault outcrops along the Shionohira Fault as well as the Coulomb stress calculations. Only a few outcrops have basement rocks of both the hanging-wall and foot-wall of the fault plane. Three of these outcrops (Kyodo-gawa, Shionohira and Betto) were selected for investigation. In addition, a fault outcrop (Nameishi-minami) located about 300 m south of the southern tip of the surface ruptures was investigated. The authors carried out observations of outcrops, polished slabs and thin sections, and performed X-ray diffraction (XRD) to fault materials. As a result, the fault zones originating from schists were investigated at Kyodo-gawa and Betto. A thick fault gouge was cut by a fault plane of the 4.11 earthquake in each outcrop. The fault materials originating from schists were fault bounded with (possibly Neogene) weakly deformed sandstone at Shionohira. A thin fault gouge was found along the fault plane of 4.11 earthquake. A small-scale fault zone with thin fault gouge was observed in Nameishi-minami. According to XRD analysis, smectite was detected in the gouges from Kyodo-gawa, Shionohira and Betto, while not in the gouge from Nameishi-minami.

  13. Investigating fault coupling: Creep and microseismicity on the Hayward fault

    Science.gov (United States)

    Evans, E. L.; Loveless, J. P.; Meade, B. J.; Burgmann, R.

    2009-12-01

    We seek to quantify the relationship between interseismic slip activity and microseismicity along the Hayward fault in the eastern San Francisco Bay Area. During the interseismic regime the Hayward fault is known to exhibit variable degrees of locking both along strike and down-dip. Background microseismicity on and near the fault has been suggested to provide independent information about the rates of interseismic creep and the boundaries of creeping regions. In particular, repeating earthquakes within the fault zone have been suggested as a proxy for fault creep rates. To investigate this relationship, we invert GPS data for microplate rotations, fault slip rates, and fault coupling using a block model that spans western United States and includes the San Andreas, Hayward, Calaveras, Rogers Creek, and Green Valley faults in the greater Bay area. The tectonic context provided by the regional scale model ensures that the slip budget across Bay Area faults is consistent with large scale tectonic motions and kinematically connected to the central San Andreas fault. We image the spatial distribution of interseismic slip on a triangulated mesh of the Hayward fault and compare the distribution of interseismic fault coupling with the number of earthquakes and the moment rate of all on-fault seismicity. We quantitatively test the hypothesis that microseismicity might define the transitions between locked and creeping regions. The calculated correlations are tested against a null hypothesis that microseismicity is randomly distributed. We further extend this investigation to the step over region between the Hayward and Calaveras faults to illuminate the interactions between linking faults.

  14. MCMini: Monte Carlo on GPGPU

    Energy Technology Data Exchange (ETDEWEB)

    Marcus, Ryan C. [Los Alamos National Laboratory

    2012-07-25

    MCMini is a proof of concept that demonstrates the possibility for Monte Carlo neutron transport using OpenCL with a focus on performance. This implementation, written in C, shows that tracing particles and calculating reactions on a 3D mesh can be done in a highly scalable fashion. These results demonstrate a potential path forward for MCNP or other Monte Carlo codes.

  15. Fault-Mechanism Simulator

    Science.gov (United States)

    Guyton, J. W.

    1972-01-01

    An inexpensive, simple mechanical model of a fault can be produced to simulate the effects leading to an earthquake. This model has been used successfully with students from elementary to college levels and can be demonstrated to classes as large as thirty students. (DF)

  16. Heat reveals faults

    Energy Technology Data Exchange (ETDEWEB)

    Weinreich, Bernhard [Solarschmiede GmbH, Muenchen (Germany). Engineering Dept.

    2010-07-01

    Gremlins cannot hide from the all-revealing view of a thermographic camera, whereby it makes no difference whether it is a roof-mounted system or a megawatt-sized farm. Just as diverse are the range of faults that, with the growing level of expertise, can now be detected and differentiated with even greater detail. (orig.)

  17. Row fault detection system

    Science.gov (United States)

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2008-10-14

    An apparatus, program product and method checks for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  18. Adaptive Fault Tolerance

    Science.gov (United States)

    1994-05-01

    center ( MOCl ) and one workstation processor (WS1) in the Adaptive Fault Tolerance 22 command center (CCE). The remaining data processing routines (GDI...78243-7063 NRAIR232 ATTN: DANIEL W. ATKINSON 9800 SAVAGE RD FT MEADE MD 20755-6000 TRUSTED INFORMATION SYSTEMS, INC. ATTN: WILLIAM C. BARKER 3060

  19. Fault-Mechanism Simulator

    Science.gov (United States)

    Guyton, J. W.

    1972-01-01

    An inexpensive, simple mechanical model of a fault can be produced to simulate the effects leading to an earthquake. This model has been used successfully with students from elementary to college levels and can be demonstrated to classes as large as thirty students. (DF)

  20. Monte Carlo methods for electromagnetics

    CERN Document Server

    Sadiku, Matthew NO

    2009-01-01

    Until now, novices had to painstakingly dig through the literature to discover how to use Monte Carlo techniques for solving electromagnetic problems. Written by one of the foremost researchers in the field, Monte Carlo Methods for Electromagnetics provides a solid understanding of these methods and their applications in electromagnetic computation. Including much of his own work, the author brings together essential information from several different publications.Using a simple, clear writing style, the author begins with a historical background and review of electromagnetic theory. After addressing probability and statistics, he introduces the finite difference method as well as the fixed and floating random walk Monte Carlo methods. The text then applies the Exodus method to Laplace's and Poisson's equations and presents Monte Carlo techniques for handing Neumann problems. It also deals with whole field computation using the Markov chain, applies Monte Carlo methods to time-varying diffusion problems, and ...

  1. Investigating the architecture of the Paganica Fault (2009 Mw 6.1 earthquake, central Italy) by integrating high-resolution multi-scale refraction tomography and detailed geological mapping

    Science.gov (United States)

    Villani, F.; Improta, L.; Pucci, S.; Civico, R.; Bruno, P. P. G.; Pantosti, D.

    2016-11-01

    We present a 2-D subsurface image of the Paganica Fault from a high-resolution refraction tomography and detailed geological investigation carried out across part of the north-western segment of the 20 km-long Paganica - San Demetrio fault-system, and which was responsible of the 6 April 2009 Mw 6.1 L'Aquila earthquake (central Italy). We acquired two seismic profiles crossing the Paganica basin with a dense-wide aperture configuration. More than 30,000 P-wave first-arrival traveltimes were input to a non-linear tomographic inversion. The obtained 250-300 m deep 2-D Vp images illuminate the shallow portion of the Paganica Fault, and depict additional unreported splays defining a complex half-graben structure. We interpret local thickening of low-Vp (tectonic clastic wedges above a high-Vp (3800-5000 m s-1) carbonate basement. These results are condensed in a 4.2 km-long section across the Paganica basin, clearly indicating that the Paganica Fault is a mature normal fault cutting the whole upper ˜10 km of the crust. We evaluate a minimum cumulative net displacement of 650 ± 90 m and a total heave of 530 ± 65 m accomplished by the Paganica Fault, respectively. In the conservative hypothesis that the extension started during the Gelasian (1.80-2.59 Ma), we obtain a minimum long-term slip-rate of 0.30 ± 0.07 mm yr-1 and an extension-rate of 0.25 ± 0.06 mm yr-1, respectively. Considering the regional averaged extensional field of ˜1 mm yr-1 obtained from geodetic and geologic analyses at 104 yr timescale, we infer that the Paganica Fault accounts for ˜ 20% of the NE-extension affecting this zone of the central Apennines axis due to the concurrent activity of other parallel normal fault-systems nearby (e.g.: the Liri, Velino-Magnola, L'Aquila-Celano, and Gran Sasso fault-systems).

  2. Metropolis Methods for Quantum Monte Carlo Simulations

    OpenAIRE

    Ceperley, D. M.

    2003-01-01

    Since its first description fifty years ago, the Metropolis Monte Carlo method has been used in a variety of different ways for the simulation of continuum quantum many-body systems. This paper will consider some of the generalizations of the Metropolis algorithm employed in quantum Monte Carlo: Variational Monte Carlo, dynamical methods for projector monte carlo ({\\it i.e.} diffusion Monte Carlo with rejection), multilevel sampling in path integral Monte Carlo, the sampling of permutations, ...

  3. Risk Communication on Earthquake Prediction Studies -"No L'Aquila quake risk" experts probed in Italy in June 2010

    Science.gov (United States)

    Oki, S.; Koketsu, K.; Kuwabara, E.; Tomari, J.

    2010-12-01

    For the previous 6 months from the L'Aquila earthquake which occurred on 6th April 2009, the seismicity in that region had been active. Having become even more active and reached to magnitude 4 earthquake on 30th March, the government held Major Risks Committee which is a part of the Civil Protection Department and is tasked with forecasting possible risks by collating and analyzing data from a variety of sources and making preventative recommendations. At the press conference immediately after the committee, they reported that "The scientific community tells us there is no danger, because there is an ongoing discharge of energy. The situation looks favorable." 6 days later, a magunitude 6.3 earthquake attacked L'Aquila and killed 308 people. On 3rd June next year, the prosecutors opened the investigation after complaints of the victims that far more people would have fled their homes that night if there had been no reassurances of the Major Risks Committee the previous week. This issue becomes widely known to the seismological society especially after an email titled "Letter of Support for Italian Earthquake Scientists" from seismologists at the National Geophysics and Volcanology Institute (INGV) sent worldwide. It says that the L'Aquila Prosecutors office indicted of manslaughter the members of the Major Risks Committee and that the charges are for failing to provide a short term alarm to the population before the earthquake struck. It is true that there is no generalized method to predict earthquakes but failing the short term alarm is not the reason for the investigation of the scientists. The chief prosecutor stated that "the committee could have provided the people with better advice", and "it wasn't the case that they did not receive any warnings, because there had been tremors". The email also requests sign-on support for the open letter to the president of Italy from Earth sciences colleagues from all over the world and collected more than 5000 signatures

  4. Lessons from the conviction of the L'Aquila seven: The standard probabilistic earthquake hazard and risk assessment is ineffective

    Science.gov (United States)

    Wyss, Max

    2013-04-01

    An earthquake of M6.3 killed 309 people in L'Aquila, Italy, on 6 April 2011. Subsequently, a judge in L'Aquila convicted seven who had participated in an emergency meeting on March 30, assessing the probability of a major event to follow the ongoing earthquake swarm. The sentence was six years in prison, a combine fine of 2 million Euros, loss of job, loss of retirement rent, and lawyer's costs. The judge followed the prosecution's accusation that the review by the Commission of Great Risks had conveyed a false sense of security to the population, which consequently did not take their usual precautionary measures before the deadly earthquake. He did not consider the facts that (1) one of the convicted was not a member of the commission and had merrily obeyed orders to bring the latest seismological facts to the discussion, (2) another was an engineer who was not required to have any expertise regarding the probability of earthquakes, (3) and two others were seismologists not invited to speak to the public at a TV interview and a press conference. This exaggerated judgment was the consequence of an uproar in the population, who felt misinformed and even mislead. Faced with a population worried by an earthquake swarm, the head of the Italian Civil Defense is on record ordering that the population be calmed, and the vice head executed this order in a TV interview one hour before the meeting of the Commission by stating "the scientific community continues to tell me that the situation is favorable and that there is a discharge of energy." The first lesson to be learned is that communications to the public about earthquake hazard and risk must not be left in the hands of someone who has gross misunderstandings about seismology. They must be carefully prepared by experts. The more significant lesson is that the approach to calm the population and the standard probabilistic hazard and risk assessment, as practiced by GSHAP, are misleading. The later has been criticized as

  5. Ultra Low Frequency (ULF European multi station magnetic field analysis before and during the 2009 earthquake at L'Aquila regarding regional geotechnical information

    Directory of Open Access Journals (Sweden)

    G. Prattes

    2011-07-01

    Full Text Available This work presents ground based Ultra Low Frequency (ULF magnetic field measurements in the frequency range from 10–15 mHz from 1 January 2008 to 14 April 2009. In this time period a strong earthquake series hit the Italian Abruzzo region around L'Aquila with the main stroke of magnitude M = 6.3 on 6 April 2009. In the frame of the South European Geomagnetic Array (SEGMA, a European collaboration runs ULF fluxgate instruments providing continuously magnetic field data recorded in mid- and south Europe. The main scientific objective is the investigation of signal variations due to seismic activity and the discrimination between other natural and human influences. The SEGMA station closest to the L'Aquila earthquake epicenter is L'Aquila observatory located in the epicenter region. For the scientific analysis we extract the nighttime period from 22:00–02:00 UT and determine the power spectral density (PSD of the horizontal (H and vertical (Z magnetic field components and the standardized polarization ratio (Z over (H. To discriminate local emissions from global geomagnetic effects, data from three SEGMA stations in distances up to 630 km from the epicenter region are analyzed and further compared to the independent global geomagnetic ∑ Kp index. Apart from indirect ionospheric effects, electromagnetic noise could be originated in the lithosphere due to tectonic mechanisms in the earthquake focus. To estimate the amplitude of assumed lithospheric electromagnetic noise emissions causing anomalies in the PSD of the (Z component, we consider magnetotelluric calculations of the electric crust conductivity in the L'Aquila region. Results found at L'Aquila observatory are interpreted with respect to the lithosphere electrical conductivity in the local observatory region, the ∑ Kp index, and further in a multi station analysis. Possible seismic related ULF

  6. Early seismogenic faults of the 2016 Accumoli-Amatrice seismic sequence (Central Apennines, Italy)

    Science.gov (United States)

    Chicco, Jessica; Pierantoni, Pietro Paolo; Centamore, Ernesto; Costa, Mario

    2017-04-01

    occurred within about an hour after the main shock. These earthquakes are arranged in two distinct and staggered clusters, confined (N, S and center) by transversal fault systems; the first (A) develops in the northern Accumoli-Norcia area with an epicenter higher frequency arranged in an NNW-SSE belt and the second (B) in the southern Amatrice area with an epicenter higher frequency arranged in an NW-SE belt. Also A includes the main shock and the largest aftershock and B lower energy earthquakes, but overall deeper. Plotting in the depths of these earthquakes shows that most likely the first to be activated was the Norcia NE-dipping fault with extensional kinematic. Therefore according to all the above mentioned it appears that the 2016 seismic sequence was caused by a CCFS segment activation and GFS / VFS was activated shortly after by accommodation. Finally according to our and to Deschamps et al. (1981) data the periodic activation of Celano-Cittareale segments, confined each time by transversal structures, caused at least the 2016 Accumoli-Amatrice, the 2009 L'Aquila and the 1979 Norcia seismic sequences and other important historical (1915, 1703, etc) Central Apennines seismic sequences.

  7. Network Fault Diagnosis Using DSM

    Institute of Scientific and Technical Information of China (English)

    Jiang Hao; Yan Pu-liu; Chen Xiao; Wu Jing

    2004-01-01

    Difference similitude matrix (DSM) is effective in reducing information system with its higher reduction rate and higher validity. We use DSM method to analyze the fault data of computer networks and obtain the fault diagnosis rules. Through discretizing the relative value of fault data, we get the information system of the fault data. DSM method reduces the information system and gets the diagnosis rules. The simulation with the actual scenario shows that the fault diagnosis based on DSM can obtain few and effective rules.

  8. Geological effects of the 2009 L’Aquila earthquake detected by COSMO-SkyMed high resolution interferometry

    Science.gov (United States)

    Chini, M.; Moro, M.; Saroli, M.; Stramondo, S.; Brunori, C.; Salvi, S.

    2009-12-01

    We investigated the surface effects of the April 6th, 2009, L’Aquila earthquake (Mw 6.3). The earthquake affected a large area in Central Italy causing strong damage to cities and villages in the epicentral region. The main goal of this work is the detection and characterization of the geological effects, such as Deep-seated Gravitational Slope Deformation (DGSD), which are gravity-driven ground movements occurring on large (1-5 km length, 100-500 m depth and width) rock volumes. To this aim we exploited the capabilities of the new High Resolution COSMO-SkyMed SAR2000 instrument, using the Differential SAR Interferometry (DInSAR) technique. We used a right ascending, Stripmap mode (35° incidence angle), coseimic image pair (April 4 - April 12) to measure the surface displacement. . We removed the topographic phase contribution using a detailed DEM at 5-m resolution . Local areas showing fringe complexities not directly attributed to the main tectonic pattern have been detected. By means of a geomorphological and geological analysis we interpreted such fringe patterns as due to ground displacement occurred along two different DGSD, one close to Roio Piano village, and the other North of the Barisciano village. The first DGSD is a sackung induced by the particular structural setting (down dip strata) and the high relief energy, whilst the second one appears to be a lateral spread of carbonatic bedrock. We unwrapped the interferogram to measure the local movements, and found 4-5 cm of LOS (Line Of Sight) displacement in both areas. The DGSD movement was triggered by the earthquake ground shaking, and, although in this case it did not result in a catastrophic collapse of the rock masses, it certainly indicates the presence of an increased ground shaking hazard in these areas. The L’Aquila earthquake is the second case study where the seismic triggering of DGSD has been recognized by DInSAR. It is worth noting that a step forward in terms of scale detail has been

  9. Lectures on Monte Carlo methods

    CERN Document Server

    Madras, Neal

    2001-01-01

    Monte Carlo methods form an experimental branch of mathematics that employs simulations driven by random number generators. These methods are often used when others fail, since they are much less sensitive to the "curse of dimensionality", which plagues deterministic methods in problems with a large number of variables. Monte Carlo methods are used in many fields: mathematics, statistics, physics, chemistry, finance, computer science, and biology, for instance. This book is an introduction to Monte Carlo methods for anyone who would like to use these methods to study various kinds of mathemati

  10. Seismic Fault Preserving Diffusion

    CERN Document Server

    Lavialle, Olivier; Germain, Christian; Donias, Marc; Guillon, Sebastien; Keskes, Naamen; Berthoumieu, Yannick

    2007-01-01

    This paper focuses on the denoising and enhancing of 3-D reflection seismic data. We propose a pre-processing step based on a non linear diffusion filtering leading to a better detection of seismic faults. The non linear diffusion approaches are based on the definition of a partial differential equation that allows us to simplify the images without blurring relevant details or discontinuities. Computing the structure tensor which provides information on the local orientation of the geological layers, we propose to drive the diffusion along these layers using a new approach called SFPD (Seismic Fault Preserving Diffusion). In SFPD, the eigenvalues of the tensor are fixed according to a confidence measure that takes into account the regularity of the local seismic structure. Results on both synthesized and real 3-D blocks show the efficiency of the proposed approach.

  11. Seismic fault preserving diffusion

    Science.gov (United States)

    Lavialle, Olivier; Pop, Sorin; Germain, Christian; Donias, Marc; Guillon, Sebastien; Keskes, Naamen; Berthoumieu, Yannick

    2007-02-01

    This paper focuses on the denoising and enhancing of 3-D reflection seismic data. We propose a pre-processing step based on a non-linear diffusion filtering leading to a better detection of seismic faults. The non-linear diffusion approaches are based on the definition of a partial differential equation that allows us to simplify the images without blurring relevant details or discontinuities. Computing the structure tensor which provides information on the local orientation of the geological layers, we propose to drive the diffusion along these layers using a new approach called SFPD (Seismic Fault Preserving Diffusion). In SFPD, the eigenvalues of the tensor are fixed according to a confidence measure that takes into account the regularity of the local seismic structure. Results on both synthesized and real 3-D blocks show the efficiency of the proposed approach.

  12. Managing Fault Management Development

    Science.gov (United States)

    McDougal, John M.

    2010-01-01

    As the complexity of space missions grows, development of Fault Management (FM) capabilities is an increasingly common driver for significant cost overruns late in the development cycle. FM issues and the resulting cost overruns are rarely caused by a lack of technology, but rather by a lack of planning and emphasis by project management. A recent NASA FM Workshop brought together FM practitioners from a broad spectrum of institutions, mission types, and functional roles to identify the drivers underlying FM overruns and recommend solutions. They identified a number of areas in which increased program and project management focus can be used to control FM development cost growth. These include up-front planning for FM as a distinct engineering discipline; managing different, conflicting, and changing institutional goals and risk postures; ensuring the necessary resources for a disciplined, coordinated approach to end-to-end fault management engineering; and monitoring FM coordination across all mission systems.

  13. Fault Tree Handbook

    Science.gov (United States)

    1981-01-01

    to be Evaluated Manufacturer Location Seismic Susceptibility Flood Susceptibility Temperature Humidity Radiation Wear-out Susceptibility Test...For the category " Seismic Susceptibility," we might define several sensitivity levels ranging from no sensitivity to extreme sensitivity, and for more... Hanford Company, Richland, Wash- ington, ARH-ST-l 12, July 1975. 40. W.E. Vesely, "Analysis of Fault Trees by Kinetic Tree Theory," Idaho Nuclear

  14. Faults in Linux

    DEFF Research Database (Denmark)

    Palix, Nicolas Jean-Michel; Thomas, Gaël; Saha, Suman

    2011-01-01

    In 2001, Chou et al. published a study of faults found by applying a static analyzer to Linux versions 1.0 through 2.4.1. A major result of their work was that the drivers directory contained up to 7 times more of certain kinds of faults than other directories. This result inspired a number...... of development and research efforts on improving the reliability of driver code. Today Linux is used in a much wider range of environments, provides a much wider range of services, and has adopted a new development and release model. What has been the impact of these changes on code quality? Are drivers still...... a major problem? To answer these questions, we have transported the experiments of Chou et al. to Linux versions 2.6.0 to 2.6.33, released between late 2003 and early 2010. We find that Linux has more than doubled in size during this period, but that the number of faults per line of code has been...

  15. Diagnosis Method for Analog Circuit Hard fault and Soft Fault

    Directory of Open Access Journals (Sweden)

    Baoru Han

    2013-09-01

    Full Text Available Because the traditional BP neural network slow convergence speed, easily falling in local minimum and the learning process will appear oscillation phenomena. This paper introduces a tolerance analog circuit hard fault and soft fault diagnosis method based on adaptive learning rate and the additional momentum algorithm BP neural network. Firstly, tolerance analog circuit is simulated by OrCAD / Pspice circuit simulation software, accurately extracts fault waveform data by matlab program automatically. Secondly, using the adaptive learning rate and momentum BP algorithm to train neural network, and then applies it to analog circuit hard fault and soft fault diagnosis. With shorter training time, high precision and global convergence effectively reduces the misjudgment, missing, it can improve the accuracy of fault diagnosis and fast.  

  16. ESR dating of fault rocks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hee Kwon [Kangwon National Univ., Chuncheon (Korea, Republic of)

    2003-02-15

    Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then grow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs. grain size shows a plateau for grains below critical size; these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected near the Gori nuclear reactor. Most of the ESR signals of fault rocks collected from the basement are saturated. This indicates that the last movement of the faults had occurred before the Quaternary period. However, ESR dates from the Oyong fault zone range from 370 to 310 ka. Results of this research suggest that long-term cyclic fault activity of the Oyong fault zone continued into the Pleistocene.

  17. Large earthquakes and creeping faults

    Science.gov (United States)

    Harris, Ruth A.

    2017-01-01

    Faults are ubiquitous throughout the Earth's crust. The majority are silent for decades to centuries, until they suddenly rupture and produce earthquakes. With a focus on shallow continental active-tectonic regions, this paper reviews a subset of faults that have a different behavior. These unusual faults slowly creep for long periods of time and produce many small earthquakes. The presence of fault creep and the related microseismicity helps illuminate faults that might not otherwise be located in fine detail, but there is also the question of how creeping faults contribute to seismic hazard. It appears that well-recorded creeping fault earthquakes of up to magnitude 6.6 that have occurred in shallow continental regions produce similar fault-surface rupture areas and similar peak ground shaking as their locked fault counterparts of the same earthquake magnitude. The behavior of much larger earthquakes on shallow creeping continental faults is less well known, because there is a dearth of comprehensive observations. Computational simulations provide an opportunity to fill the gaps in our understanding, particularly of the dynamic processes that occur during large earthquake rupture and arrest.

  18. A census of dense cores in the Aquila cloud complex: SPIRE/PACS observations from the Herschel Gould Belt survey

    CERN Document Server

    Konyves, V; Men'shchikov, A; Palmeirim, P; Arzoumanian, D; Schneider, N; Roy, A; Didelon, P; Maury, A; Shimajiri, Y; Di Francesco, J; Bontemps, S; Peretto, N; Benedettini, M; Bernard, J -Ph; Elia, D; Griffin, M J; Hill, T; Kirk, J; Ladjelate, B; Marsh, K; Martin, P G; Motte, F; Luong, Q Nguyen; Pezzuto, S; Roussel, H; Rygl, K L J; Sadavoy, S I; Schisano, E; Spinoglio, L; Ward-Thompson, D; White, G J

    2015-01-01

    We present and discuss the results of the Herschel Gould Belt survey observations in a ~11 deg^2 area of the Aquila molecular cloud complex at d~260 pc, imaged with the SPIRE/PACS cameras from 70 to 500 micron. We identify a complete sample of starless dense cores and embedded protostars in this region, and analyze their global properties and spatial distributions. We find a total of 651 starless cores, ~60% of which are gravitationally bound prestellar cores, and they will likely form stars in the future. We also detect 58 protostellar cores. The core mass function (CMF) derived for the prestellar cores is very similar in shape to the stellar initial mass function (IMF), supporting the earlier view that there is a close physical link between the IMF and the CMF. The global shift in mass scale observed between the CMF and the IMF is consistent with a typical star formation efficiency of ~40%. By comparing the numbers of starless cores to the number of young stellar objects, we estimate that the lifetime of pr...

  19. Wing tucks are a response to atmospheric turbulence in the soaring flight of the steppe eagle Aquila nipalensis

    Science.gov (United States)

    Reynolds, Kate V.; Thomas, Adrian L. R.; Taylor, Graham K.

    2014-01-01

    Turbulent atmospheric conditions represent a challenge to stable flight in soaring birds, which are often seen to drop their wings in a transient motion that we call a tuck. Here, we investigate the mechanics, occurrence and causation of wing tucking in a captive steppe eagle Aquila nipalensis, using ground-based video and onboard inertial instrumentation. Statistical analysis of 2594 tucks, identified automatically from 45 flights, reveals that wing tucks occur more frequently under conditions of higher atmospheric turbulence. Furthermore, wing tucks are usually preceded by transient increases in airspeed, load factor and pitch rate, consistent with the bird encountering a headwind gust. The tuck itself immediately follows a rapid drop in angle of attack, caused by a downdraft or nose-down pitch motion, which produces a rapid drop in load factor. Positive aerodynamic loading acts to elevate the wings, and the resulting aerodynamic moment must therefore be balanced in soaring by an opposing musculoskeletal moment. Wing tucking presumably occurs when the reduction in the aerodynamic moment caused by a drop in load factor is not met by an equivalent reduction in the applied musculoskeletal moment. We conclude that wing tucks represent a gust response precipitated by a transient drop in aerodynamic loading. PMID:25320064

  20. The Star of Bethlehem is Not the Nova DO Aquilae (Nor Any Other Nova, Supernova, or Comet)

    CERN Document Server

    Schaefer, Bradley E

    2013-01-01

    The Star of Bethlehem is only known from a few verses in the Gospel of Matthew, with the Star inspiring and leading the Magi (i.e., Persian astrologers) to Jerusalem and ultimately worshipping the young Jesus Christ in Bethlehem. In the last four centuries, astronomers have put forth over a dozen greatly different naturalistic explanations, all involving astronomical events, often a bright nova, supernova, or comet. This paper will evaluate one prominent recent proposal, that the Star was a 'recurrent nova' now catalogued as DO Aquilae, and provide three refutations. In particular, (1) DO Aql is certainly not a recurrent nova, but rather an ordinary nova with a recurrence time scale of over a million years, (2) in its 1925 eruption, DO Aql certainly never got brighter than 8.5 mag, and the physics of the system proves that it could never get to the required luminosity of a supernova, and (3) the Magi were astrologers who had no recognition or interpretation for novae (or supernovae or comets) so any such even...

  1. The BLAST View of the Star Forming Region in Aquila (ell=45deg,b=0deg)

    CERN Document Server

    Rivera-Ingraham, Alana; Bock, James J; Chapin, Edward L; Devlin, Mark J; Dicker, Simon R; Griffin, Matthew; Gundersen, Joshua O; Halpern, Mark; Hargrave, Peter C; Hughes, David H; Klein, Jeff; Marsden, Gaelen; Martin, Peter G; Mauskopf, Philip; Netterfield, Calvin B; Olmi, Luca; Patanchon, Guillaume; Rex, Marie; Scott, Douglas; Semisch, Christopher; Truch, Matthew D P; Tucker, Carole; Tucker, Gregory S; Viero, Marco P; Wiebe, Donald V

    2010-01-01

    We have carried out the first general submillimeter analysis of the field towards GRSMC 45.46+0.05, a massive star forming region in Aquila. The deconvolved 6 deg^2 (3\\degree X 2\\degree) maps provided by BLAST in 2005 at 250, 350, and 500 micron were used to perform a preliminary characterization of the clump population previously investigated in the infrared, radio, and molecular maps. Interferometric CORNISH data at 4.8 GHz have also been used to characterize the Ultracompact HII regions (UCHIIRs) within the main clumps. By means of the BLAST maps we have produced an initial census of the submillimeter structures that will be observed by Herschel, several of which are known Infrared Dark Clouds (IRDCs). Our spectral energy distributions of the main clumps in the field, located at ~7 kpc, reveal an active population with temperatures of T~35-40 K and masses of ~10^3 Msun for a dust emissivity index beta=1.5. The clump evolutionary stages range from evolved sources, with extended HII regions and prominent IR ...

  2. Biotelemetry data for golden eagles (Aquila chrysaetos) captured in coastal southern California, November 2014–February 2016

    Science.gov (United States)

    Tracey, Jeff A.; Madden, Melanie C.; Sebes, Jeremy B.; Bloom, Peter H.; Katzner, Todd E.; Fisher, Robert N.

    2016-04-21

    The status of golden eagles (Aquila chrysaetos) in coastal southern California is unclear. To address this knowledge gap, the U.S. Geological Survey (USGS) in collaboration with local, State, and other Federal agencies began a multi-year survey and tracking program of golden eagles to address questions regarding habitat use, movement behavior, nest occupancy, genetic population structure, and human impacts on eagles. Golden eagle trapping and tracking efforts began in October 2014 and continued until early March 2015. During the first trapping season that focused on San Diego County, we captured 13 golden eagles (8 females and 5 males). During the second trapping season that began in November 2015, we focused on trapping sites in San Diego, Orange, and western Riverside Counties. By February 23, 2016, we captured an additional 14 golden eagles (7 females and 7 males). In this report, biotelemetry data were collected between November 22, 2014, and February 23, 2016. The location data for eagles ranged as far north as San Luis Obispo, California, and as far south as La Paz, Baja California, Mexico.

  3. YSO jets in the Galactic Plane from UWISH2: II - Outflow Luminosity and Length distributions in Serpens and Aquila

    CERN Document Server

    Ioannidis, G

    2012-01-01

    Jets and outflows accompany the mass accretion process in protostars and young stellar objects. Using a large and unbiased sample, they can be used to study statistically the local feedback they provide and the typical mass accretion history. Here we analyse such a sample of Molecular Hydrogen emission line Objects in the Serpens and Aquila part of the Galactic Plane. Distances are measured by foreground star counts with an accuracy of 25%. The resulting spacial distribution and outflow luminosities indicate that our objects sample the formation of intermediate mass objects. The outflows are unable to provide a sizeable fraction of energy and momentum to support, even locally, the turbulence levels in their surrounding molecular clouds. The fraction of parsec scale flows is one quarter and the typical dynamical jet age of the order of 1E4yrs. Groups of emission knots are ejected every 1E3yrs. This might indicate that low level accretion rate fluctuations and not FU-Ori type events are responsible for the epis...

  4. Estimation of occupancy, breeding success, and predicted abundance of golden eagles (Aquila chrysaetos) in the Diablo Range, California, 2014

    Science.gov (United States)

    Wiens, J. David; Kolar, Patrick S.; Fuller, Mark R.; Hunt, W. Grainger; Hunt, Teresa

    2015-01-01

    We used a multistate occupancy sampling design to estimate occupancy, breeding success, and abundance of territorial pairs of golden eagles (Aquila chrysaetos) in the Diablo Range, California, in 2014. This method uses the spatial pattern of detections and non-detections over repeated visits to survey sites to estimate probabilities of occupancy and successful reproduction while accounting for imperfect detection of golden eagles and their young during surveys. The estimated probability of detecting territorial pairs of golden eagles and their young was less than 1 and varied with time of the breeding season, as did the probability of correctly classifying a pair’s breeding status. Imperfect detection and breeding classification led to a sizeable difference between the uncorrected, naïve estimate of the proportion of occupied sites where successful reproduction was observed (0.20) and the model-based estimate (0.30). The analysis further indicated a relatively high overall probability of landscape occupancy by pairs of golden eagles (0.67, standard error = 0.06), but that areas with the greatest occupancy and reproductive potential were patchily distributed. We documented a total of 138 territorial pairs of golden eagles during surveys completed in the 2014 breeding season, which represented about one-half of the 280 pairs we estimated to occur in the broader 5,169-square kilometer region sampled. The study results emphasize the importance of accounting for imperfect detection and spatial heterogeneity in studies of site occupancy, breeding success, and abundance of golden eagles.

  5. The Change of the Orbital Periods Across Eruptions and the Ejected Mass For Recurrent Novae CI Aquilae and U Scorpii

    CERN Document Server

    Schaefer, Bradley E

    2011-01-01

    I report on the cumulative results from a program started 24 years ago designed to measure the orbital period change of recurrent novae (RNe) across an eruption. The goal is to use the orbital period change to measure the mass ejected during each eruption as the key part of trying to measure whether the RNe white dwarfs are gaining or losing mass over an entire eruption cycle, and hence whether they can be progenitors for Type Ia supernovae. This program has now been completed for two eclipsing RNe; CI Aquilae (CI Aql) across its eruption in 2000 and U Scorpii (U Sco) across its eruption in 1999. For CI Aql, I present 78 eclipse times from 1991-2009 (including four during the tail of the 2000 eruption) plus two eclipses from 1926 and 1935. For U Sco, I present 67 eclipse times, including 46 times during quiescence from 1989-2009, plus 21 eclipse times in the tails of the 1945, 1999, and 2010 eruptions. The eclipse times during the tails of eruptions are systematically and substantially shifted with respect to...

  6. The Smart Ring Experience in l’Aquila (Italy: Integrating Smart Mobility Public Services with Air Quality Indexes

    Directory of Open Access Journals (Sweden)

    Maria-Gabriella Villani

    2016-12-01

    Full Text Available This work presents the “City Dynamics and Smart Environment” activities of the Smart Ring project, a model for the smart city, based on the integration of sustainable urban transport services and environmental monitoring over a 4–5-km circular path, the “Smart Ring”, around the historical center of l’Aquila (Italy. We describe our pilot experience performed during an experimental on-demand public service electric bus, “SmartBus”, which was equipped with a multi-parametric air quality low-cost gas electrochemical sensor platform, “NASUS IV”. For five days (28–29 August 2014 and 1–3 September 2014, the sensor platform was installed inside the SmartBus and measured air quality gas compounds (nitrogen dioxide, carbon oxide, sulfur dioxide, hydrogen sulfide during the service. Data were collected and analyzed on the bases of an air quality index, which provided qualitative insights on the air status potentially experienced by the users. The results obtained are in agreement with the synoptic meteorological conditions, the urban background air quality reference measurements and the potential traffic flow variations. Furthermore, they indicated that the air quality status was influenced by the gas component NO 2 , followed by H 2 S, SO 2 and CO. We discuss the features of our campaign, and we highlight the potential, limitations and key factors to consider for future project designs.

  7. Case study of seismic performance assessment of irregular RC buildings: hospital structure of Avezzano (L'Aquila, Italy)

    Science.gov (United States)

    Ferraioli, Massimiliano

    2015-03-01

    Most published studies on inelastic earthquake response of non-symmetric buildings are based on simplified inelastic, highly idealized models, while general conclusions regarding the inelastic torsional response of multistory building are still lacking. This paper aims to provide a useful contribution in the study of the torsional response of real irregular buildings. To this aim, the manuscript reports the comprehensive study on the seismic vulnerability of an irregular RC building: the hospital building of Avezzano (L'Aquila Italy). For this multi-story building, which is irregular in both plan and elevation, the application of nonlinear static evaluation procedures is by no means straightforward. The study proposes a nonlinear static procedure based on pushover analysis under the multimodal distribution of lateral loads and a capacity spectrum method. This pushover procedure accounts for mass distribution, higher modes contribution and mode-shapes correlation. Furthermore, due to its non-iterative feature, it avoids problems of non-convergence and multiple solutions of the conventional capacity spectrum method. Applied to a real case study, the procedure is used to investigate, in a 3D plan irregular building, the sensitivity of torsional inelastic response to lateral force distribution, higher modes contribution, accidental eccentricity and controlled point for monitoring the target displacement.

  8. On a reported effect in ionospheric TEC around the time of the 6 April 2009 L'Aquila earthquake

    Science.gov (United States)

    Masci, Fabrizio; Thomas, Jeremy N.; Secan, James A.

    2017-09-01

    In a report published in Advances in Space Research, Nenovski et al. (2015) analyse ionospheric TEC (total electron content) data from GPS measurements around the time of the 6 April 2009 Mw 6. 1 L'Aquila (Italy) earthquake. According to the authors, TEC difference (DTEC) calculated from two GPS (Global Positioning System) receivers in central Italy shows a hump-like shape (an increase followed by a decrease) during the hours just before and shortly after the main shock. They maintain that the hump-like shape is anomalous and may be related to the earthquake. We show that the DTEC increase in the hours before the shock, as well as its subsequent slow decrease, does not have any characteristic that might support a possible relationship with the earthquake. We have also conducted our own independent analysis using the same GPS data analysed by Nenovski et al. (2015). We have found a diurnal variation in DTEC time series that shows hump-like shapes like that reported by Nenovski et al. (2015) throughout the investigated period. This demonstrates that the hump-like shape in DTEC close to the time of the 6 April earthquake is not anomalous and cannot be considered a possible earthquake-related effect.

  9. Genetic structure and viability selection in the golden eagle (Aquila chrysaetos), a vagile raptor with a Holarctic distribution

    Science.gov (United States)

    Doyle, Jacqueline M.; Katzner, Todd Eli; Roemer, Gary; Cain, James W.; Millsap, Brian; McIntyre, Carol; Sonsthagen, Sarah A.; Fernandez, Nadia B.; Wheeler, Maria; Bulut, Zafer; Bloom, Peter; DeWoody, J. Andrew

    2016-01-01

    Molecular markers can reveal interesting aspects of organismal ecology and evolution, especially when surveyed in rare or elusive species. Herein, we provide a preliminary assessment of golden eagle (Aquila chrysaetos) population structure in North America using novel single nucleotide polymorphisms (SNPs). These SNPs included one molecular sexing marker, two mitochondrial markers, 85 putatively neutral markers that were derived from noncoding regions within large intergenic intervals, and 74 putatively nonneutral markers found in or very near protein-coding genes. We genotyped 523 eagle samples at these 162 SNPs and quantified genotyping error rates and variability at each marker. Our samples corresponded to 344 individual golden eagles as assessed by unique multilocus genotypes. Observed heterozygosity of known adults was significantly higher than of chicks, as was the number of heterozygous loci, indicating that mean zygosity measured across all 159 autosomal markers was an indicator of fitness as it is associated with eagle survival to adulthood. Finally, we used chick samples of known provenance to test for population differentiation across portions of North America and found pronounced structure among geographic sampling sites. These data indicate that cryptic genetic population structure is likely widespread in the golden eagle gene pool, and that extensive field sampling and genotyping will be required to more clearly delineate management units within North America and elsewhere.

  10. Monte Carlo integration on GPU

    OpenAIRE

    Kanzaki, J.

    2010-01-01

    We use a graphics processing unit (GPU) for fast computations of Monte Carlo integrations. Two widely used Monte Carlo integration programs, VEGAS and BASES, are parallelized on GPU. By using $W^{+}$ plus multi-gluon production processes at LHC, we test integrated cross sections and execution time for programs in FORTRAN and C on CPU and those on GPU. Integrated results agree with each other within statistical errors. Execution time of programs on GPU run about 50 times faster than those in C...

  11. Shallow subsurface imaging of the Piano di Pezza active normal fault (central Italy) by high-resolution refraction and electrical resistivity tomography coupled with time-domain electromagnetic data

    Science.gov (United States)

    Villani, Fabio; Tulliani, Valerio; Sapia, Vincenzo; Fierro, Elisa; Civico, Riccardo; Pantosti, Daniela

    2015-12-01

    The Piano di Pezza fault is the central section of the 35 km long L'Aquila-Celano active normal fault-system in the central Apennines of Italy. Although palaeoseismic data document high Holocene vertical slip rates (˜1 mm yr-1) and a remarkable seismogenic potential of this fault, its subsurface setting and Pleistocene cumulative displacement are still poorly known. We investigated for the first time the shallow subsurface of a key section of the main Piano di Pezza fault splay by means of high-resolution seismic and electrical resistivity tomography coupled with time-domain electromagnetic soundings (TDEM). Our surveys cross a ˜5-m-high fault scarp that was generated by repeated surface-rupturing earthquakes displacing Holocene alluvial fans. We provide 2-D Vp and resistivity images, which show significant details of the fault structure and the geometry of the shallow basin infill material down to 50 m depth. Our data indicate that the upper fault termination has a sub-vertical attitude, in agreement with palaeoseismological trench evidence, whereas it dips ˜50° to the southwest in the deeper part. We recognize some low-velocity/low-resistivity regions in the fault hangingwall that we relate to packages of colluvial wedges derived from scarp degradation, which may represent the record of some Holocene palaeo-earthquakes. We estimate a ˜13-15 m throw of this fault splay since the end of the Last Glacial Maximum (˜18 ka), leading to a 0.7-0.8 mm yr-1 throw rate that is quite in accordance with previous palaeoseismic estimation of Holocene vertical slip rates. The 1-D resistivity models from TDEM soundings collected along the trace of the electrical profile significantly match with 2-D resistivity images. Moreover, they indicate that in the fault hangingwall, ˜200 m away from the surface fault trace, the pre-Quaternary carbonate basement is at ˜90-100 m depth. We therefore provide a minimal ˜150-160 m estimate of the cumulative throw of the Piano di Pezza

  12. Inverting Source Time Functions to determine the fault kinematic characteristics

    Science.gov (United States)

    Toraldo Serra, E. M.; Orefice, A.; Emolo, A.; Zollo, A.

    2012-04-01

    to move from a high- to low-wavelength description of kinematic parameters on the fault. The optimal model parameter set is chosen according to Akaike Information Criterion [1974]. We present results for some synthetic tests and an application to a seismic events occurred during the 2009 L'Aquila (Central Italy) seismic sequence. In particular, we analyzed a small aftershock occurred on 2009 April 9, at 04:43:09 (UTC) characterized by a seismic moment of 1.07e+15 Nm (Mw 4). We found: a slip distribution, with an average value of 0.8 cm, characterized by a main slip patch located NW of the hypocenter and a rupture velocity distribution (mean value of 2.3 km/s) with a strong acceleration in the same direction.

  13. Imaging of subsurface faults using refraction migration with fault flooding

    Science.gov (United States)

    Metwally, Ahmed; Hanafy, Sherif; Guo, Bowen; Kosmicki, Maximillian

    2017-08-01

    We propose a novel method for imaging shallow faults by migration of transmitted refraction arrivals. The assumption is that there is a significant velocity contrast across the fault boundary that is underlain by a refracting interface. This procedure, denoted as refraction migration with fault flooding, largely overcomes the difficulty in imaging shallow faults with seismic surveys. Numerical results successfully validate this method on three synthetic examples and two field-data sets. The first field-data set is next to the Gulf of Aqaba and the second example is from a seismic profile recorded in Arizona. The faults detected by refraction migration in the Gulf of Aqaba data were in agreement with those indicated in a P-velocity tomogram. However, a new fault is detected at the end of the migration image that is not clearly seen in the traveltime tomogram. This result is similar to that for the Arizona data where the refraction image showed faults consistent with those seen in the P-velocity tomogram, except that it also detected an antithetic fault at the end of the line. This fault cannot be clearly seen in the traveltime tomogram due to the limited ray coverage.

  14. Imaging of Subsurface Faults using Refraction Migration with Fault Flooding

    KAUST Repository

    Metwally, Ahmed

    2017-05-31

    We propose a novel method for imaging shallow faults by migration of transmitted refraction arrivals. The assumption is that there is a significant velocity contrast across the fault boundary that is underlain by a refracting interface. This procedure, denoted as refraction migration with fault flooding, largely overcomes the difficulty in imaging shallow faults with seismic surveys. Numerical results successfully validate this method on three synthetic examples and two field-data sets. The first field-data set is next to the Gulf of Aqaba and the second example is from a seismic profile recorded in Arizona. The faults detected by refraction migration in the Gulf of Aqaba data were in agreement with those indicated in a P-velocity tomogram. However, a new fault is detected at the end of the migration image that is not clearly seen in the traveltime tomogram. This result is similar to that for the Arizona data where the refraction image showed faults consistent with those seen in the P-velocity tomogram, except it also detected an antithetic fault at the end of the line. This fault cannot be clearly seen in the traveltime tomogram due to the limited ray coverage.

  15. Critical features in electromagnetic anomalies detected prior to the L'Aquila earthquake

    CERN Document Server

    Contoyiannis, Y F; Kopanas, J; Antonopoulos, G; Contoyianni, L; Eftaxias, K

    2009-01-01

    Electromagnetic (EM) emissions in a wide frequency spectrum ranging from kHz to MHz are produced by opening cracks, which can be considered as the so-called precursors of general fracture. We emphasize that the MHz radiation appears earlier than the kHz in both laboratory and geophysical scale. An important challenge in this field of research is to distinguish characteristic epochs in the evolution of precursory EM activity and identify them with the equivalent last stages in the earthquake (EQ) preparation process. Recently, we proposed the following two epochs/stages model: (i) The second epoch, which includes the finally emerged strong impulsive kHz EM emission is due to the fracture of the high strength large asperities that are distributed along the activated fault sustaining the system. (ii) The first epoch, which includes the initially emerged MHz EM radiation is thought to be due to the fracture of a highly heterogeneous system that surrounds the family of asperities. A catastrophic EQ of magnitude Mw...

  16. Mechanical stratigraphy and normal faulting

    Science.gov (United States)

    Ferrill, David A.; Morris, Alan P.; McGinnis, Ronald N.; Smart, Kevin J.; Wigginton, Sarah S.; Hill, Nicola J.

    2017-01-01

    Mechanical stratigraphy encompasses the mechanical properties, thicknesses, and interface properties of rock units. Although mechanical stratigraphy often relates directly to lithostratigraphy, lithologic description alone does not adequately describe mechanical behavior. Analyses of normal faults with displacements of millimeters to 10's of kilometers in mechanically layered rocks reveal that mechanical stratigraphy influences nucleation, failure mode, fault geometry, displacement gradient, displacement distribution, fault core and damage zone characteristics, and fault zone deformation processes. The relationship between normal faulting and mechanical stratigraphy can be used either to predict structural style using knowledge of mechanical stratigraphy, or conversely to interpret mechanical stratigraphy based on characterization of the structural style. This review paper explores a range of mechanical stratigraphic controls on normal faulting illustrated by natural and modeled examples.

  17. Fault Tolerant Wind Farm Control

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2013-01-01

    with best at a wind turbine control level. However, some faults are better dealt with at the wind farm control level, if the wind turbine is located in a wind farm. In this paper a benchmark model for fault detection and isolation, and fault tolerant control of wind turbines implemented at the wind farm...... control level is presented. The benchmark model includes a small wind farm of nine wind turbines, based on simple models of the wind turbines as well as the wind and interactions between wind turbines in the wind farm. The model includes wind and power references scenarios as well as three relevant fault...... scenarios. This benchmark model is used in an international competition dealing with Wind Farm fault detection and isolation and fault tolerant control....

  18. Handling Software Faults with Redundancy

    Science.gov (United States)

    Carzaniga, Antonio; Gorla, Alessandra; Pezzè, Mauro

    Software engineering methods can increase the dependability of software systems, and yet some faults escape even the most rigorous and methodical development process. Therefore, to guarantee high levels of reliability in the presence of faults, software systems must be designed to reduce the impact of the failures caused by such faults, for example by deploying techniques to detect and compensate for erroneous runtime conditions. In this chapter, we focus on software techniques to handle software faults, and we survey several such techniques developed in the area of fault tolerance and more recently in the area of autonomic computing. Since practically all techniques exploit some form of redundancy, we consider the impact of redundancy on the software architecture, and we propose a taxonomy centered on the nature and use of redundancy in software systems. The primary utility of this taxonomy is to classify and compare techniques to handle software faults.

  19. USING MUTATION IN FAULT LOCALIZATION

    Directory of Open Access Journals (Sweden)

    Chenglong Sun

    2016-05-01

    Full Text Available Fault localization is time-consuming and difficult, which makes it the bottleneck of the debugging progress. To help facilitate this task, there exist many fault localization techniques that help narrow down the region of the suspicious code in a program. Better accuracy in fault localization is achieved from heavy computation cost. Fault localization techniques that can effectively locate faults also manifest slow response rate. In this paper, we promote the use of pre-computing to distribute the time-intensive computations to the idle period of coding phase, in order to speed up such techniques and achieve both low-cost and high accuracy. We raise the research problems of finding suitable techniques that can be pre-computed and adapt it to the pre-computing paradigm in a continuous integration environment. Further, we use an existing fault localization technique to demonstrate our research exploration, and shows visions and challenges of the related methodologies.

  20. Fault-tolerant quantum computing with color codes

    CERN Document Server

    Landahl, Andrew J; Rice, Patrick R

    2011-01-01

    We present and analyze protocols for fault-tolerant quantum computing using color codes. We present circuit-level schemes for extracting the error syndrome of these codes fault-tolerantly. We further present an integer-program-based decoding algorithm for identifying the most likely error given the syndrome. We simulated our syndrome extraction and decoding algorithms against three physically-motivated noise models using Monte Carlo methods, and used the simulations to estimate the corresponding accuracy thresholds for fault-tolerant quantum error correction. We also used a self-avoiding walk analysis to lower-bound the accuracy threshold for two of these noise models. We present and analyze two architectures for fault-tolerantly computing with these codes: one with 2D arrays of qubits are stacked atop each other and one in a single 2D substrate. Our analysis demonstrates that color codes perform slightly better than Kitaev's surface codes when circuit details are ignored. When these details are considered, w...

  1. Fault detection and isolation of sensors in aeration control systems.

    Science.gov (United States)

    Carlsson, Bengt; Zambrano, Jesús

    2016-01-01

    In this paper, we consider the problem of fault detection (FD) and isolation in the aeration system of an activated sludge process. For this study, the dissolved oxygen in each aerated zone is assumed to be controlled automatically. As the basis for an FD method we use the ratio of air flow rates into different zones. The method is evaluated in two scenarios: using the Benchmark Simulation Model no. 1 (BSM1) by Monte Carlo simulations and using data from a wastewater treatment plant. The FD method shows good results for a correct and early FD and isolation.

  2. Final Technical Report: PV Fault Detection Tool.

    Energy Technology Data Exchange (ETDEWEB)

    King, Bruce Hardison [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Christian Birk [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    The PV Fault Detection Tool project plans to demonstrate that the FDT can (a) detect catastrophic and degradation faults and (b) identify the type of fault. This will be accomplished by collecting fault signatures using different instruments and integrating this information to establish a logical controller for detecting, diagnosing and classifying each fault.

  3. Seismological Studies for Tensile Faults

    Directory of Open Access Journals (Sweden)

    Gwo-Bin Ou

    2008-01-01

    Full Text Available A shear slip fault, an equivalence of a double couple source, has often been assumed to be a kinematic source model in ground motion simulation. Estimation of seismic moment based on the shear slip model indicates the size of an earthquake. However, if the dislocation of the hanging wall relative to the footwall includes not only a shear slip tangent to the fault plane but also expansion and compression normal to the fault plane, the radiating seismic waves will feature differences from those out of the shear slip fault. Taking account of the effects resulting from expansion and compression to a fault plane, we can resolve the tension and pressure axes as well as the fault plane solution more exactly from ground motions than previously, and can evaluate how far a fault zone opens or contracts during a developing rupture. In addition to a tensile angle and Poisson¡¦s ratio for the medium, a tensile fault with five degrees of freedom has been extended from the shear slip fault with only three degrees of freedom, strike, dip, and slip.

  4. Fault-Tree Compiler Program

    Science.gov (United States)

    Butler, Ricky W.; Martensen, Anna L.

    1992-01-01

    FTC, Fault-Tree Compiler program, is reliability-analysis software tool used to calculate probability of top event of fault tree. Five different types of gates allowed in fault tree: AND, OR, EXCLUSIVE OR, INVERT, and M OF N. High-level input language of FTC easy to understand and use. Program supports hierarchical fault-tree-definition feature simplifying process of description of tree and reduces execution time. Solution technique implemented in FORTRAN, and user interface in Pascal. Written to run on DEC VAX computer operating under VMS operating system.

  5. Causes of automotive turbocharger faults

    Directory of Open Access Journals (Sweden)

    Jan FILIPCZYK

    2013-01-01

    Full Text Available This paper presents the results of examinations of turbocharger damages. The analysis of the causes of faults in 100 engines with turbochargers of cars, buses and trucks has been carried out. The incidence and structure of turbocharged engine faults has been compared to the causes of faults of naturally aspirated engines. The cause of damage, the possibility of early detection, the time between overhaul and the impact on engine operation for each case of fault was carried out as well. The results of examinations allowed to determine the most common causes of damages and how to prevent them.

  6. An Overview of Transmission Line Protection by Artificial Neural Network: Fault Detection, Fault Classification, Fault Location, and Fault Direction Discrimination

    Directory of Open Access Journals (Sweden)

    Anamika Yadav

    2014-01-01

    Full Text Available Contemporary power systems are associated with serious issues of faults on high voltage transmission lines. Instant isolation of fault is necessary to maintain the system stability. Protective relay utilizes current and voltage signals to detect, classify, and locate the fault in transmission line. A trip signal will be sent by the relay to a circuit breaker with the purpose of disconnecting the faulted line from the rest of the system in case of a disturbance for maintaining the stability of the remaining healthy system. This paper focuses on the studies of fault detection, fault classification, fault location, fault phase selection, and fault direction discrimination by using artificial neural networks approach. Artificial neural networks are valuable for power system applications as they can be trained with offline data. Efforts have been made in this study to incorporate and review approximately all important techniques and philosophies of transmission line protection reported in the literature till June 2014. This comprehensive and exhaustive survey will reduce the difficulty of new researchers to evaluate different ANN based techniques with a set of references of all concerned contributions.

  7. Integrated design of fault reconstruction and fault-tolerant control against actuator faults using learning observers

    Science.gov (United States)

    Jia, Qingxian; Chen, Wen; Zhang, Yingchun; Li, Huayi

    2016-12-01

    This paper addresses the problem of integrated fault reconstruction and fault-tolerant control in linear systems subject to actuator faults via learning observers (LOs). A reconfigurable fault-tolerant controller is designed based on the constructed LO to compensate for the influence of actuator faults by stabilising the closed-loop system. An integrated design of the proposed LO and the fault-tolerant controller is explored such that their performance can be simultaneously considered and their coupling problem can be effectively solved. In addition, such an integrated design is formulated in terms of linear matrix inequalities (LMIs) that can be conveniently solved in a unified framework using LMI optimisation technique. At last, simulation studies on a micro-satellite attitude control system are provided to verify the effectiveness of the proposed approach.

  8. Hydrothermal anomalies before the 2009 Mw 6.3 L'Aquila earthquake in Italy referring to the geospheres coupling effects

    Science.gov (United States)

    Wu, Lixin; Zheng, Shuo; Qin, Kai; De Santis, Angelo; Liu, Shanjun

    2016-04-01

    A large number of precursory anomalies of the 2009 L'Aquila EQ were reported after the shocking, including thermal properties, electric and magnetic fields, gas emissions and seismicity. Previous studies on the seismic b-value are also insufficient, which is possibly a proxy of crust stress conditions and could therewith act as a crude stress-meter wherever seismicity is observed in lithosphere. Nevertheless, the reported anomalies have not been so far synergically analyzed to interpret or prove the potential coupling process among different geospheres. In this paper, the spatio-temporal evolution of several hydrothermal parameters related to the coversphere and atmosphere, including soil moisture, soil temperature, near-surface air temperature, and precipitable water, was comprehensively investigated. Air temperature and atmospheric aerosol were also statistically analyzed in time series with ground observations. An abnormal enhancement of aerosol occurred on March 30, 2009 and thus proved quasi-synchronous anomalies among the hydrothermal parameters from March 29 to 31 in particular places geo-related to tectonic thrusts and local topography. In additional, the three-dimensional (3D) visualization analysis of b-value revealed that regional stress accumulated to a high level, particularly in the L'Aquila basin and around regional large thrusts. This links logically and spatially the multiple observations on coversphere and atmosphere with that on lithosphere. Finally, the coupling effects of geospheres were discussed, and a conceptual LCA coupling mode was proposed to interpret the possible mechanisms of the multiple quasi-synchronous anomalies preceding the L'Aquila EQ. Results indicate that CO2-rich fluids in deep crust might have played a significant role in the local LCA coupling process.

  9. Ground motions recorded in Rome during the April 2009 L’Aquila seismic sequence: site response and comparison with ground‐motion predictions based on a global dataset

    Science.gov (United States)

    Caserta, Arrigo; Boore, David; Rovelli, Antonio; Govoni, Aladino; Marra, Fabrizio; Monica, Gieseppe Della; Boschi, Enzo

    2013-01-01

    The mainshock and moderate‐magnitude aftershocks of the 6 April 2009 M 6.3 L’Aquila seismic sequence, about 90 km northeast of Rome, provided the first earthquake ground‐motion recordings in the urban area of Rome. Before those recordings were obtained, the assessments of the seismic hazard in Rome were based on intensity observations and theoretical considerations. The L’Aquila recordings offer an unprecedented opportunity to calibrate the city response to central Apennine earthquakes—earthquakes that have been responsible for the largest damage to Rome in historical times. Using the data recorded in Rome in April 2009, we show that (1) published theoretical predictions of a 1 s resonance in the Tiber valley are confirmed by observations showing a significant amplitude increase in response spectra at that period, (2) the empirical soil‐transfer functions inferred from spectral ratios are satisfactorily fit through 1D models using the available geological, geophysical, and laboratory data, but local variability can be large for individual events, (3) response spectra for the motions recorded in Rome from the L’Aquila earthquakes are significantly amplified in the radial component at periods near 1 s, even at a firm site on volcanic rocks, and (4) short‐period response spectra are smaller than expected when compared to ground‐motion predictions from equations based on a global dataset, whereas the observed response spectra are higher than expected for periods near 1 s.

  10. Why local people did not present a problem in the 2016 Kumamoto earthquake, Japan though people accused in the 2009 L'Aquila earthquake?

    Science.gov (United States)

    Sugimoto, M.

    2016-12-01

    Risk communication is a big issues among seismologists after the 2009 L'Aquila earthquake all over the world. A lot of people remember 7 researchers as "L'Aquila 7" were accused in Italy. Seismologists said it is impossible to predict an earthquake by science technology today and join more outreach activities. "In a subsequent inquiry of the handling of the disaster, seven members of the Italian National Commission for the Forecast and Prevention of Major Risks were accused of giving "inexact, incomplete and contradictory" information about the danger of the tremors prior to the main quake. On 22 October 2012, six scientists and one ex-government official were convicted of multiple manslaughter for downplaying the likelihood of a major earthquake six days before it took place. They were each sentenced to six years' imprisonment (Wikipedia)". Finally 6 scientists are not guilty. The 2016 Kumamoto earthquake hit Kyushu, Japan in April. They are very similar seismological situations between the 2016 Kumamoto earthquake and the 2009 L'Aquila earthquake. The foreshock was Mj6.5 and Mw6.2 in 14 April 2016. The main shock was Mj7.3 and Mw7.0. Japan Metrological Agency (JMA) misleaded foreshock as mainshock before main shock occured. 41 people died by the main shock in Japan. However local people did not accused scientists in Japan. It has been less big earhquakes around 100 years in Kumamoto. Poeple was not so matured that they treated earthquake information in Kyushu, Japan. How are there differences between Japan and Italy? We learn about outreach activities for sciencits from this case.

  11. Pediatric Epidemic of Salmonella enterica Serovar Typhimurium in the Area of L’Aquila, Italy, Four Years after a Catastrophic Earthquake

    Directory of Open Access Journals (Sweden)

    Giovanni Nigro

    2016-05-01

    Full Text Available Background: A Salmonella enterica epidemic occurred in children of the area of L’Aquila (Central Italy, Abruzzo region between June 2013 and October 2014, four years after the catastrophic earthquake of 6 April 2009. Methods: Clinical and laboratory data were collected from hospitalized and ambulatory children. Routine investigations for Salmonella infection were carried out on numerous alimentary matrices of animal origin and sampling sources for drinking water of the L’Aquila district, including pickup points of the two main aqueducts. Results: Salmonella infection occurred in 155 children (83 females: 53%, aged 1 to 15 years (mean 2.10. Of these, 44 children (28.4% were hospitalized because of severe dehydration, electrolyte abnormalities, and fever resistant to oral antipyretic and antibiotic drugs. Three children (1.9% were reinfected within four months after primary infection by the same Salmonella strain. Four children (2.6%, aged one to two years, were coinfected by rotavirus. A seven-year old child had a concomitant right hip joint arthritis. The isolated strains, as confirmed in about the half of cases or probable/possible in the remaining ones, were identified as S. enterica serovar Typhimurium [4,5:i:-], monophasic variant. Aterno river, bordering the L’Aquila district, was recognized as the main responsible source for the contamination of local crops and vegetables derived from polluted crops. Conclusions: The high rate of hospitalized children underlines the emergence of a highly pathogenic S. enterica strain probably subsequent to the contamination of the spring water sources after geological changes occurred during the catastrophic earthquake.

  12. [The hazards of reconstruction: anthropology of dwelling and social health risk in the L'Aquila (Central Italy) post-earthquake].

    Science.gov (United States)

    Ciccozzi, Antonello

    2016-01-01

    Even starting from the purpose of restoring the damage caused by a natural disaster, the post-earthquake reconstructions imply the risk of triggering a set of social disasters that may affect the public health sphere. In the case of the L'Aquila earthquake this risk seems to emerge within the urban planning on two levels of dwelling: at a landscape level, where there has been a change in the shape of the city towards a sprawling-sprinkling process; at an architectural level, on the problematic relationship between the politics and the poetics of cultural heritage protection and the goal to get restoration works capable to ensure the citizens seismic safety.

  13. Ultra Low Frequency (ULF) European multi station magnetic field analysis before and during the 2009 earthquake at L'Aquila regarding regional geotechnical information

    OpenAIRE

    Prattes, G.; Schwingenschuh, K.; Eichelberger, H. U.; Magnes, W.; Boudjada, M.; M. Stachel; Vellante, M.; U. Villante; Wesztergom, V.; Nenovski, P.

    2011-01-01

    This work presents ground based Ultra Low Frequency (ULF) magnetic field measurements in the frequency range from 10–15 mHz from 1 January 2008 to 14 April 2009. In this time period a strong earthquake series hit the Italian Abruzzo region around L'Aquila with the main stroke of magnitude M = 6.3 on 6 April 2009. In the frame of the South European Geomagnetic Array (SEGMA), a European collaboration runs ULF fluxgate instruments providing continuously magnetic field data re...

  14. Multilevel sequential Monte Carlo samplers

    KAUST Repository

    Beskos, Alexandros

    2016-08-29

    In this article we consider the approximation of expectations w.r.t. probability distributions associated to the solution of partial differential equations (PDEs); this scenario appears routinely in Bayesian inverse problems. In practice, one often has to solve the associated PDE numerically, using, for instance finite element methods which depend on the step-size level . hL. In addition, the expectation cannot be computed analytically and one often resorts to Monte Carlo methods. In the context of this problem, it is known that the introduction of the multilevel Monte Carlo (MLMC) method can reduce the amount of computational effort to estimate expectations, for a given level of error. This is achieved via a telescoping identity associated to a Monte Carlo approximation of a sequence of probability distributions with discretization levels . ∞>h0>h1⋯>hL. In many practical problems of interest, one cannot achieve an i.i.d. sampling of the associated sequence and a sequential Monte Carlo (SMC) version of the MLMC method is introduced to deal with this problem. It is shown that under appropriate assumptions, the attractive property of a reduction of the amount of computational effort to estimate expectations, for a given level of error, can be maintained within the SMC context. That is, relative to exact sampling and Monte Carlo for the distribution at the finest level . hL. The approach is numerically illustrated on a Bayesian inverse problem. © 2016 Elsevier B.V.

  15. Fault Diagnosis and Fault Handling for Autonomous Aircraft

    DEFF Research Database (Denmark)

    Hansen, Søren

    Unmanned Aerial vehicles (UAVs) or drones are used increasingly for missions where piloted aircraft are unsuitable. The unmanned aircraft has a number of advantages with respect to size, weight and manoeuvrability that makes it possible for them to solve tasks that an aircraft previously has been...... that the fault is discovered in time such that appropriate actions can be taken. That could either be the aircraft controlling computer taking the fault into account or a human operator that intervenes. Detection of faults that occur during flight is exactly the subject of this thesis. Safety towards faults...... to another type of aircraft with different parameters. Amongst the main findings of this research project is a method to handle faults on the UAV’s pitot tube, which measures the aircraft speed. A set of software redundancies based on GPS velocity information and engine thrust are used to detect abnormal...

  16. Study on Fault Current of DFIG during Slight Fault Condition

    Directory of Open Access Journals (Sweden)

    Xiangping Kong

    2013-04-01

    Full Text Available In order to ensure the safety of DFIG when severe fault happens, crowbar protection is adopted. But during slight fault condition, the crowbar protection will not trip, and the DFIG is still excited by AC-DC-AC converter. In this condition, operation characteristics of the converter have large influence on the fault current characteristics of DFIG. By theoretical analysis and digital simulation, the fault current characteristics of DFIG during slight voltage dips are studied. And the influence of controller parameters of converter on the fault current characteristics is analyzed emphatically. It builds a basis for the construction of relay protection which is suitable for the power gird with accession of DFIG.

  17. Homogeneous Earthquake Faulting, Stress and Fault Strength on Kilometer Scales

    Science.gov (United States)

    Hardebeck, J. L.

    2006-12-01

    I investigate small-scale fault structure using three new high-quality focal mechanism datasets of small (MLoma Prieta earthquake. I quantify the degree of mechanism variability on a range of length scales, by comparing the hypocentral distance between every pair of events and the angular difference between their focal mechanisms. I explore the implications of focal mechanism variability for the heterogeneity or homogeneity of stress and fault strength on various length scales. Focal mechanisms are very similar, often identical to within the 1σ uncertainty of ~25°, on small length scales of effect of uncertainty in earthquake locations and focal mechanisms on the apparent mechanism variability. The result that fault geometry, stress and fault strength are generally homogeneous on ~10 km length scales is encouraging for understanding earthquake physics. It may be possible to measure these parameters with enough precision to be useful in studying and modeling large earthquakes and the behavior of major faults.

  18. Fault Management Design Strategies

    Science.gov (United States)

    Day, John C.; Johnson, Stephen B.

    2014-01-01

    Development of dependable systems relies on the ability of the system to determine and respond to off-nominal system behavior. Specification and development of these fault management capabilities must be done in a structured and principled manner to improve our understanding of these systems, and to make significant gains in dependability (safety, reliability and availability). Prior work has described a fundamental taxonomy and theory of System Health Management (SHM), and of its operational subset, Fault Management (FM). This conceptual foundation provides a basis to develop framework to design and implement FM design strategies that protect mission objectives and account for system design limitations. Selection of an SHM strategy has implications for the functions required to perform the strategy, and it places constraints on the set of possible design solutions. The framework developed in this paper provides a rigorous and principled approach to classifying SHM strategies, as well as methods for determination and implementation of SHM strategies. An illustrative example is used to describe the application of the framework and the resulting benefits to system and FM design and dependability.

  19. Fault Management Design Strategies

    Science.gov (United States)

    Day, John C.; Johnson, Stephen B.

    2014-01-01

    Development of dependable systems relies on the ability of the system to determine and respond to off-nominal system behavior. Specification and development of these fault management capabilities must be done in a structured and principled manner to improve our understanding of these systems, and to make significant gains in dependability (safety, reliability and availability). Prior work has described a fundamental taxonomy and theory of System Health Management (SHM), and of its operational subset, Fault Management (FM). This conceptual foundation provides a basis to develop framework to design and implement FM design strategies that protect mission objectives and account for system design limitations. Selection of an SHM strategy has implications for the functions required to perform the strategy, and it places constraints on the set of possible design solutions. The framework developed in this paper provides a rigorous and principled approach to classifying SHM strategies, as well as methods for determination and implementation of SHM strategies. An illustrative example is used to describe the application of the framework and the resulting benefits to system and FM design and dependability.

  20. Equilibrium Statistics: Monte Carlo Methods

    Science.gov (United States)

    Kröger, Martin

    Monte Carlo methods use random numbers, or ‘random’ sequences, to sample from a known shape of a distribution, or to extract distribution by other means. and, in the context of this book, to (i) generate representative equilibrated samples prior being subjected to external fields, or (ii) evaluate high-dimensional integrals. Recipes for both topics, and some more general methods, are summarized in this chapter. It is important to realize, that Monte Carlo should be as artificial as possible to be efficient and elegant. Advanced Monte Carlo ‘moves’, required to optimize the speed of algorithms for a particular problem at hand, are outside the scope of this brief introduction. One particular modern example is the wavelet-accelerated MC sampling of polymer chains [406].

  1. Accelerometer having integral fault null

    Science.gov (United States)

    Bozeman, Richard J., Jr. (Inventor)

    1995-01-01

    An improved accelerometer is introduced. It comprises a transducer responsive to vibration in machinery which produces an electrical signal related to the magnitude and frequency of the vibration; and a decoding circuit responsive to the transducer signal which produces a first fault signal to produce a second fault signal in which ground shift effects are nullified.

  2. Hard Fault Analysis of Trivium

    CERN Document Server

    Yupu, Hu; Yiwei, Zhang

    2009-01-01

    Fault analysis is a powerful attack to stream ciphers. Up to now, the major idea of fault analysis is to simplify the cipher system by injecting some soft faults. We call it soft fault analysis. As a hardware-oriented stream cipher, Trivium is weak under soft fault analysis. In this paper we consider another type of fault analysis of stream cipher, which is to simplify the cipher system by injecting some hard faults. We call it hard fault analysis. We present the following results about such attack to Trivium. In Case 1 with the probability not smaller than 0.2396, the attacker can obtain 69 bits of 80-bits-key. In Case 2 with the probability not smaller than 0.2291, the attacker can obtain all of 80-bits-key. In Case 3 with the probability not smaller than 0.2291, the attacker can partially solve the key. In Case 4 with non-neglectable probability, the attacker can obtain a simplified cipher, with smaller number of state bits and slower non-linearization procedure. In Case 5 with non-neglectable probability,...

  3. Fault-tolerant linear optical quantum computing with small-amplitude coherent States.

    Science.gov (United States)

    Lund, A P; Ralph, T C; Haselgrove, H L

    2008-01-25

    Quantum computing using two coherent states as a qubit basis is a proposed alternative architecture with lower overheads but has been questioned as a practical way of performing quantum computing due to the fragility of diagonal states with large coherent amplitudes. We show that using error correction only small amplitudes (alpha>1.2) are required for fault-tolerant quantum computing. We study fault tolerance under the effects of small amplitudes and loss using a Monte Carlo simulation. The first encoding level resources are orders of magnitude lower than the best single photon scheme.

  4. Change in regional cerebral function in l'aquila earthquake survivors with post-traumatic stress disorder: preliminary findings.

    Science.gov (United States)

    Catalucci, A; Mazza, M; Fasano, F; Ciutti, E; Anselmi, M; Roncone, R; Di Salle, F; Gallucci, M

    2011-03-29

    Subjects with post-traumatic stress disorder (PTSD) present a diminished or blunted emotional response, sometimes called "emotional numbing" (EN), that constitutes one of the central symptoms in PTSD. Symptoms of EN include diminished interest in activities, feeling detached or estranged from others, and restricted range of affect (American Psychiatric Association, 2000). The present work studied the emotional components in individuals with PTSD with the principal aim of investigating subjects' functional alteration in the limbic regions, insula and frontal cortex during an emotional task compared with healthy subjects. Ten subjects with PTSD (survivors of the 6.3 magnitude earthquake of April 6, 2009 in L'Aquila) and ten healthy controls underwent fMRI. PTSD was diagnosed according to DSM-IV-R (APA 2000). All subjects underwent fMRI while viewing content-neutral and emotional stimuli. Data analysis revealed that PTSD subjects had significantly greater cerebral activation in particular in the right anterior insula and in bilateral inferior frontal gyrus. Our data suggest that there is a change in the activation of brain areas responsible for emotional processing in patients with PTSD and are consistent with previous findings demonstrating hyperactivation in frontolimbic structures during emotional tasks. Our study suggests that close personal experience may be critical in engaging the neural mechanisms underlying the emotional modulation of memory. Our findings provide evidence that significant alterations in brain function, similar in many ways to those observed in PTSD, can be seen shortly after major traumatic experiences, highlighting the need for early evaluation and intervention for trauma survivors.

  5. Long-term blood pressure changes induced by the 2009 L'Aquila earthquake: assessment by 24 h ambulatory monitoring.

    Science.gov (United States)

    Giorgini, Paolo; Striuli, Rinaldo; Petrarca, Marco; Petrazzi, Luisa; Pasqualetti, Paolo; Properzi, Giuliana; Desideri, Giovambattista; Omboni, Stefano; Parati, Gianfranco; Ferri, Claudio

    2013-09-01

    An increased rate of cardiovascular and cerebrovascular events has been described during and immediately after earthquakes. In this regard, few data are available on long-term blood pressure control in hypertensive outpatients after an earthquake. We evaluated the long-term effects of the April 2009 L'Aquila earthquake on blood pressure levels, as detected by 24 h ambulatory blood pressure monitoring. Before/after (mean±s.d. 6.9±4.5/14.2±5.1 months, respectively) the earthquake, the available 24 h ambulatory blood pressure monitoring data for the same patients were extracted from our database. Quake-related daily life discomforts were evaluated through interviews. We enrolled 47 patients (25 female, age 52±14 years), divided into three groups according to antihypertensive therapy changes after versus before the earthquake: unchanged therapy (n=24), increased therapy (n=17) and reduced therapy (n=6). Compared with before the quake, in the unchanged therapy group marked increases in 24 h (P=0.004), daytime (P=0.01) and nighttime (P=0.02) systolic blood pressure were observed after the quake. Corresponding changes in 24 h (P=0.005), daytime (P=0.01) and nighttime (P=0.009) diastolic blood pressure were observed. Daily life discomforts were reported more frequently in the unchanged therapy and increased therapy groups than the reduced therapy group (P=0.025 and P=0.018, respectively). In conclusion, this study shows that patients with unchanged therapy display marked blood pressure increments up to more than 1 year after an earthquake, as well as long-term quake-related discomfort. Our data suggest that particular attention to blood pressure levels and adequate therapy modifications should be considered after an earthquake, not only early after the event but also months later.

  6. [Sleep disturbances and spatial memory deficits in post-traumatic stress disorder: the case of L'Aquila (Central Italy)].

    Science.gov (United States)

    Ferrara, Michele; Mazza, Monica; Curcio, Giuseppe; Iaria, Giuseppe; De Gennaro, Luigi; Tempesta, Daniela

    2016-01-01

    Altered sleep is a common and central symptom of post-traumatic stress disorder (PTSD). In fact, sleep disturbances are included in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnostic criteria for PTSD. However, it has been hypothesized that sleep disturbances are crucially involved in the aetiology of PTSD, rather than being solely a symptom arising secondarily from this disorder. Therefore, knowing the long-term effects of a trauma can be essential to establish the need of specific interventions for the prevention and treatment of mental disorders that may persist years after a traumatic experience. In one study we showed, for the first time, that even after a period of two years people exposed to a catastrophic disaster such as the L'Aquila earthquake continue to suffer from a reduced sleep quality. Moreover, we observed that sleep quality scores decreased as a function of the proximity to the epicentre, suggesting that the psychological effects of an earthquake may be pervasive and long-lasting. It has been widely shown that disruption of sleep by acute stress may lead to deterioration in memory processing. In fact, in a recent study we observed alterations in spatial memory in PTSD subjects. Our findings indicated that PTSD is accompanied by an impressive deficit in forming a cognitive map of the environment, as well as in sleep-dependent memory consolidation. The fact that this deterioration was correlated to the subjective sleep disturbances in our PTSD group demonstrates the existence of an intimate relationship between sleep, memory consolidation, and stress.

  7. Stress Drops of the 1997-1998 Colfiorito, Central Italy Earthquakes: Hints for a Common Behaviour of Normal Faults in the Apennines

    Science.gov (United States)

    Rovelli, Antonio; Calderoni, Giovanna

    2014-10-01

    Stress drop estimates of moderate-magnitude earthquakes in the Umbria-Marche region, in the northern Apennines, exhibit a large scatter. For the two M w 5.7 and 6.0 main shocks of 26 September 1997 near Colfiorito, several papers resulted in stress drop estimates of 20 MPa, but values as low as 2-3 MPa were proposed as well. Also for the largest aftershocks ( M w > 4), estimates spread from earthquakes in a broad magnitude interval (1.7 ≤ M w ≤ 6.0). We have found that the mainshock-aftershock sequences result in stress drops of 2-5 MPa at M w ≥ 5.6, with an average tendency to decrease at smaller magnitudes where stress drop variability increases. These findings confirm the source scaling recently assessed through Empirical Green's Function deconvolution for another well-monitored seismic sequence of normal-faulting earthquakes, which struck the city of L'Aquila in the central Apennines in April 2009. The similar scaling law of the two areas suggests common mechanisms of stress release for the shallow normal faults in the Apennines. The propensity of smaller earthquakes to increase in variability, with a tendency toward smaller stress drops, may reflect an effect of fault strength heterogeneities for smaller size ruptures.

  8. Monte Carlo Hamiltonian: Linear Potentials

    Institute of Scientific and Technical Information of China (English)

    LUO Xiang-Qian; LIU Jin-Jiang; HUANG Chun-Qing; JIANG Jun-Qin; Helmut KROGER

    2002-01-01

    We further study the validity of the Monte Carlo Hamiltonian method. The advantage of the method,in comparison with the standard Monte Carlo Lagrangian approach, is its capability to study the excited states. Weconsider two quantum mechanical models: a symmetric one V(x) = |x|/2; and an asymmetric one V(x) = ∞, forx < 0 and V(x) = x, for x ≥ 0. The results for the spectrum, wave functions and thermodynamical observables are inagreement with the analytical or Runge-Kutta calculations.

  9. Proton Upset Monte Carlo Simulation

    Science.gov (United States)

    O'Neill, Patrick M.; Kouba, Coy K.; Foster, Charles C.

    2009-01-01

    The Proton Upset Monte Carlo Simulation (PROPSET) program calculates the frequency of on-orbit upsets in computer chips (for given orbits such as Low Earth Orbit, Lunar Orbit, and the like) from proton bombardment based on the results of heavy ion testing alone. The software simulates the bombardment of modern microelectronic components (computer chips) with high-energy (.200 MeV) protons. The nuclear interaction of the proton with the silicon of the chip is modeled and nuclear fragments from this interaction are tracked using Monte Carlo techniques to produce statistically accurate predictions.

  10. Fault tolerant control for switched linear systems

    CERN Document Server

    Du, Dongsheng; Shi, Peng

    2015-01-01

    This book presents up-to-date research and novel methodologies on fault diagnosis and fault tolerant control for switched linear systems. It provides a unified yet neat framework of filtering, fault detection, fault diagnosis and fault tolerant control of switched systems. It can therefore serve as a useful textbook for senior and/or graduate students who are interested in knowing the state-of-the-art of filtering, fault detection, fault diagnosis and fault tolerant control areas, as well as recent advances in switched linear systems.  

  11. Fault isolatability conditions for linear systems

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, Henrik

    2006-01-01

    In this paper, we shall show that an unlimited number of additive single faults can be isolated under mild conditions if a general isolation scheme is applied. Multiple faults are also covered. The approach is algebraic and is based on a set representation of faults, where all faults within a set...... the faults have occurred. The last step is a fault isolation (FI) of the faults occurring in a specific fault set, i.e. equivalent with the standard FI step. A simple example demonstrates how to turn the algebraic necessary and sufficient conditions into explicit algorithms for designing filter banks, which...

  12. Fault Current Characteristics of the DFIG under Asymmetrical Fault Conditions

    Directory of Open Access Journals (Sweden)

    Fan Xiao

    2015-09-01

    Full Text Available During non-severe fault conditions, crowbar protection is not activated and the rotor windings of a doubly-fed induction generator (DFIG are excited by the AC/DC/AC converter. Meanwhile, under asymmetrical fault conditions, the electrical variables oscillate at twice the grid frequency in synchronous dq frame. In the engineering practice, notch filters are usually used to extract the positive and negative sequence components. In these cases, the dynamic response of a rotor-side converter (RSC and the notch filters have a large influence on the fault current characteristics of the DFIG. In this paper, the influence of the notch filters on the proportional integral (PI parameters is discussed and the simplified calculation models of the rotor current are established. Then, the dynamic performance of the stator flux linkage under asymmetrical fault conditions is also analyzed. Based on this, the fault characteristics of the stator current under asymmetrical fault conditions are studied and the corresponding analytical expressions of the stator fault current are obtained. Finally, digital simulation results validate the analytical results. The research results are helpful to meet the requirements of a practical short-circuit calculation and the construction of a relaying protection system for the power grid with penetration of DFIGs.

  13. Absolute age determination of quaternary faults

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Chang Sik; Lee, Seok Hoon; Choi, Man Sik [Korea Basic Science Institute, Seoul (Korea, Republic of)] (and others)

    2000-03-15

    To constrain the age of neotectonic fault movement, Rb-Sr, K-Ar, U-series disequilibrium, C-14 and Be-10 methods were applied to the fault gouges, fracture infillings and sediments from the Malbang, Ipsil, Wonwonsa faults faults in the Ulsan fault zone, Yangsan fault in the Yeongdeog area and southeastern coastal area. Rb-Sr and K-Ar data imply that the fault movement of the Ulan fault zone initiated at around 30 Ma and preliminary dating result for the Yang san fault is around 70 Ma in the Yeongdeog area. K-Ar and U-series disequilibrium dating results for fracture infillings in the Ipsil fault are consistent with reported ESR ages. Radiocarbon ages of quaternary sediments from the Jeongjari area are discordant with stratigraphic sequence. Carbon isotope data indicate a difference of sedimentry environment for those samples. Be-10 dating results for the Suryum fault area are consistent with reported OSL results.

  14. Remote Sensing of Urban Microclimate Change in L'Aquila City (Italy) after Post-Earthquake Depopulation in an Open Source GIS Environment.

    Science.gov (United States)

    Baiocchi, Valerio; Zottele, Fabio; Dominici, Donatella

    2017-02-19

    This work reports a first attempt to use Landsat satellite imagery to identify possible urban microclimate changes in a city center after a seismic event that affected L'Aquila City (Abruzzo Region, Italy), on 6 April 2009. After the main seismic event, the collapse of part of the buildings, and the damaging of most of them, with the consequence of an almost total depopulation of the historic city center, may have caused alterations to the microclimate. This work develops an inexpensive work flow-using Landsat Enhanced Thematic Mapper Plus (ETM+) scenes-to construct the evolution of urban land use after the catastrophic main seismic event that hit L'Aquila. We hypothesized, that, possibly, before the event, the temperature was higher in the city center due to the presence of inhabitants (and thus home heating); while the opposite case occurred in the surrounding areas, where new settlements of inhabitants grew over a period of a few months. We decided not to look to independent meteorological data in order to avoid being biased in their investigations; thus, only the smallest dataset of Landsat ETM+ scenes were considered as input data in order to describe the thermal evolution of the land surface after the earthquake. We managed to use the Landsat archive images to provide thermal change indications, useful for understanding the urban changes induced by catastrophic events, setting up an easy to implement, robust, reproducible, and fast procedure.

  15. Remote Sensing of Urban Microclimate Change in L’Aquila City (Italy after Post-Earthquake Depopulation in an Open Source GIS Environment

    Directory of Open Access Journals (Sweden)

    Valerio Baiocchi

    2017-02-01

    Full Text Available This work reports a first attempt to use Landsat satellite imagery to identify possible urban microclimate changes in a city center after a seismic event that affected L’Aquila City (Abruzzo Region, Italy, on 6 April 2009. After the main seismic event, the collapse of part of the buildings, and the damaging of most of them, with the consequence of an almost total depopulation of the historic city center, may have caused alterations to the microclimate. This work develops an inexpensive work flow—using Landsat Enhanced Thematic Mapper Plus (ETM+ scenes—to construct the evolution of urban land use after the catastrophic main seismic event that hit L’Aquila. We hypothesized, that, possibly, before the event, the temperature was higher in the city center due to the presence of inhabitants (and thus home heating; while the opposite case occurred in the surrounding areas, where new settlements of inhabitants grew over a period of a few months. We decided not to look to independent meteorological data in order to avoid being biased in their investigations; thus, only the smallest dataset of Landsat ETM+ scenes were considered as input data in order to describe the thermal evolution of the land surface after the earthquake. We managed to use the Landsat archive images to provide thermal change indications, useful for understanding the urban changes induced by catastrophic events, setting up an easy to implement, robust, reproducible, and fast procedure.

  16. Architectural survey and documentation for the conservation of historic urban centre. The case study of L’Aquila after the earthquake of 2009.

    Directory of Open Access Journals (Sweden)

    Mario Centofanti

    2012-11-01

    Full Text Available The Seminar is part of the activities of the Research of National Interest MIUR PRIN 2008 financed by Italian Ministry for Education University and Research, titled “Complex models for architectural and urban heritage”,  with the participation  of five research units of Italian universities. Naturally the research unit of L’Aquila University has studied the historical centre of L’Aquila, hit by the seismic event of April 6, 2009. It includes, in its  168 hectares, an architectural and artistic heritage of great value. Three and a half years after the event, the intervention strategy made by authorities still can not give concrete solutions. Therefore it’s necessary to design a Conservation Project of the historical centre, with the aim of a proper formal and figurative re-composition, and of a coordination of individual interventions. The Project have to be based on buildings’ and historical city’s broad and organic knowledge system.

  17. A qualitative study of the seismo-ionospheric precursors prior to the 6 April 2009 earthquake in L'Aquila, Italy

    Directory of Open Access Journals (Sweden)

    G. S. Tsolis

    2010-01-01

    Full Text Available In this paper we use the Cross Correlation analysis method in conjunction with the Empirical Mode Decomposition to analyze foF2 signals collected from Rome, Athens and San Vito ionospheric stations, in order to verify the existence of seismo-ionospheric precursors prior to M=6.3 L'Aquila earthquake in Italy. The adaptive nature of EMD allows for removing the geophysical noise from the foF2 signals, and then to calculate the correlation coefficient between them. According to the cross correlation coefficient theory, we expect the stations which located inside the earthquake preparation area, as evaluated using Dobrovolsky equation, to capture the ionospheric disturbances generated by the seismic event. On the other hand the stations outside of this area are expected to remain unaffected. The results of our study are in accordance with the theoretical model, evidencing ionospheric modification prior to L'Aquila earthquake in a certain area around the epicenter. However, it was found that the selection of stations at the limits of the theoretically estimated earthquake preparation area is not the best choice when the cross correlation method is applied, since the modification of the ionosphere over these stations may not be enough for the ionospheric precursors to appear. Our experimental results also show that when a seismic event constitutes the main shock after a series of pre-seismic activity, precursors may appear as early as 22 days prior to the event.

  18. Remote Sensing of Urban Microclimate Change in L’Aquila City (Italy) after Post-Earthquake Depopulation in an Open Source GIS Environment

    Science.gov (United States)

    Baiocchi, Valerio; Zottele, Fabio; Dominici, Donatella

    2017-01-01

    This work reports a first attempt to use Landsat satellite imagery to identify possible urban microclimate changes in a city center after a seismic event that affected L’Aquila City (Abruzzo Region, Italy), on 6 April 2009. After the main seismic event, the collapse of part of the buildings, and the damaging of most of them, with the consequence of an almost total depopulation of the historic city center, may have caused alterations to the microclimate. This work develops an inexpensive work flow—using Landsat Enhanced Thematic Mapper Plus (ETM+) scenes—to construct the evolution of urban land use after the catastrophic main seismic event that hit L’Aquila. We hypothesized, that, possibly, before the event, the temperature was higher in the city center due to the presence of inhabitants (and thus home heating); while the opposite case occurred in the surrounding areas, where new settlements of inhabitants grew over a period of a few months. We decided not to look to independent meteorological data in order to avoid being biased in their investigations; thus, only the smallest dataset of Landsat ETM+ scenes were considered as input data in order to describe the thermal evolution of the land surface after the earthquake. We managed to use the Landsat archive images to provide thermal change indications, useful for understanding the urban changes induced by catastrophic events, setting up an easy to implement, robust, reproducible, and fast procedure. PMID:28218724

  19. Monte Carlo Particle Lists: MCPL

    CERN Document Server

    Kittelmann, Thomas; Knudsen, Erik B; Willendrup, Peter; Cai, Xiao Xiao; Kanaki, Kalliopi

    2016-01-01

    A binary format with lists of particle state information, for interchanging particles between various Monte Carlo simulation applications, is presented. Portable C code for file manipulation is made available to the scientific community, along with converters and plugins for several popular simulation packages.

  20. Applications of Monte Carlo Methods in Calculus.

    Science.gov (United States)

    Gordon, Sheldon P.; Gordon, Florence S.

    1990-01-01

    Discusses the application of probabilistic ideas, especially Monte Carlo simulation, to calculus. Describes some applications using the Monte Carlo method: Riemann sums; maximizing and minimizing a function; mean value theorems; and testing conjectures. (YP)

  1. Deep Fault Drilling Project—Alpine Fault, New Zealand

    Directory of Open Access Journals (Sweden)

    Rupert Sutherland

    2009-09-01

    Full Text Available The Alpine Fault, South Island, New Zealand, constitutes a globally significant natural laboratory for research into how active plate-bounding continental faults work and, in particular, how rocks exposed at the surface today relate to deep-seated processes of tectonic deformation, seismogenesis, and mineralization. The along-strike homogeneity of the hanging wall, rapid rate of dextral-reverse slip on an inclined fault plane, and relatively shallow depths to mechanical and chemical transitions make the Alpine Fault and the broader South Island plate boundary an important international site for multi-disciplinary research and a realistic target for an ambitious long-term program of scientific drilling investigations.

  2. Reduction of Faults in Software Testing by Fault Domination"

    Institute of Scientific and Technical Information of China (English)

    XU Shiyi

    2007-01-01

    Although mutation testing is one of the practical ways of enhancing test effectiveness in software testing, it could be sometimes infeasible in practical work for a large scale software so that the mutation testing becomes time-consuming and even in prohibited time. Therefore, the number of faults assumed to exist in the software under test should be reduced so as to be able to confine the time complexity of test within a reasonable period of time. This paper utilizes the concept of fault dominance and equivalence, which has long been employed in hardware testing, for revealing a novel way of reducing the number of faults assumed to hide in software systems. Once the number of faults assumed in software is decreased sharply, the effectiveness of mutation testing will be greatly enhanced and become a feasible way of software testing. Examples and experimental results are presented to illustrate the effectiveness and the helpfulness of the technology proposed in the paper.

  3. (U) Introduction to Monte Carlo Methods

    Energy Technology Data Exchange (ETDEWEB)

    Hungerford, Aimee L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-20

    Monte Carlo methods are very valuable for representing solutions to particle transport problems. Here we describe a “cook book” approach to handling the terms in a transport equation using Monte Carlo methods. Focus is on the mechanics of a numerical Monte Carlo code, rather than the mathematical foundations of the method.

  4. Monte Carlo simulations and benchmark studies at CERN's accelerator chain

    CERN Document Server

    AUTHOR|(CDS)2083190; Brugger, Markus

    2016-01-01

    Mixed particle and energy radiation fields present at the Large Hadron Collider (LHC) and its accelerator chain are responsible for failures on electronic devices located in the vicinity of the accelerator beam lines. These radiation effects on electronics and, more generally, the overall radiation damage issues have a direct impact on component and system lifetimes, as well as on maintenance requirements and radiation exposure to personnel who have to intervene and fix existing faults. The radiation environments and respective radiation damage issues along the CERN’s accelerator chain were studied in the framework of the CERN Radiation to Electronics (R2E) project and are hereby presented. The important interplay between Monte Carlo simulations and radiation monitoring is also highlighted.

  5. Expert System Detects Power-Distribution Faults

    Science.gov (United States)

    Walters, Jerry L.; Quinn, Todd M.

    1994-01-01

    Autonomous Power Expert (APEX) computer program is prototype expert-system program detecting faults in electrical-power-distribution system. Assists human operators in diagnosing faults and deciding what adjustments or repairs needed for immediate recovery from faults or for maintenance to correct initially nonthreatening conditions that could develop into faults. Written in Lisp.

  6. Fault Detection for Diesel Engine Actuator

    DEFF Research Database (Denmark)

    Blanke, M.; Bøgh, S.A.; Jørgensen, R.B.

    1994-01-01

    Feedback control systems are vulnerable to faults in control loop sensors and actuators, because feedback actions may cause abrupt responses and process damage when faults occur.......Feedback control systems are vulnerable to faults in control loop sensors and actuators, because feedback actions may cause abrupt responses and process damage when faults occur....

  7. Active fault diagnosis by temporary destabilization

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob

    2006-01-01

    An active fault diagnosis method for parametric or multiplicative faults is proposed. The method periodically adds a term to the controller that for a short period of time renders the system unstable if a fault has occurred, which facilitates rapid fault detection. An illustrative example is given....

  8. From fault classification to fault tolerance for multi-agent systems

    CERN Document Server

    Potiron, Katia; Taillibert, Patrick

    2013-01-01

    Faults are a concern for Multi-Agent Systems (MAS) designers, especially if the MAS are built for industrial or military use because there must be some guarantee of dependability. Some fault classification exists for classical systems, and is used to define faults. When dependability is at stake, such fault classification may be used from the beginning of the system's conception to define fault classes and specify which types of faults are expected. Thus, one may want to use fault classification for MAS; however, From Fault Classification to Fault Tolerance for Multi-Agent Systems argues that

  9. Facebook, quality of life and mental health outcomes in post-disaster urban environments: the L’Aquila earthquake experience

    Directory of Open Access Journals (Sweden)

    Francesco eMasedu

    2014-12-01

    Full Text Available BackgroundAn understudied area of interest in post-disaster public health is individuals’ use of social networks as a potential determinant of quality of life (QOL and mental health outcomes. A population-based cross-sectional study was carried out to examine whether continual use of online social networking (Facebook in an adult population following a massive earthquake was correlated with prevalence of depression and PTSD and QOL outcomes. MethodsParticipants were a sample of 890 adults aged 25 to 54 who had been exposed to the L'Aquila earthquake of 2009. Definition of user required a daily connection to the Facebook online social network for more than one hour per day from at least two years.Depression and PTSD were assessed using the Screening Questionnaire for Disaster Mental Health (SQD. QOL outcomes were measured using the WHOQOL-BREF instrument. Logistic regression was carried out to calculate the prevalence odds ratios (POR for social network use and other covariates.ResultsTwo hundred and twenty one of 423 (52.2% men, and 195 of 383 (50.9% women, had been using Facebook as social network for at least two years prior to our assessment. Social network use correlated with both depression and PTSD, after adjusting for gender. A halved risk of depression was found in users vs. non-users (POR 0.50±0.16. Similarly, a halved risk of PTSD in users vs. non-users (POR 0.47±0.14 was found. Both men and women using online social networks had significantly higher QOL scores in the psychological and social domains of the WHOQOL-BREF.ConclusionsSocial network use among adults 25 to 54 years old has a positive impact on mental health and QOL outcomes in the years following a disaster. The use of social networks may be an important tool for coping with the mental health outcomes of disruptive natural disasters, helping to maintain, if not improve, QOL in terms of social relationships and psychological distress.

  10. A Collision Risk Model to Predict Avian Fatalities at Wind Facilities: An Example Using Golden Eagles, Aquila chrysaetos.

    Directory of Open Access Journals (Sweden)

    Leslie New

    Full Text Available Wind power is a major candidate in the search for clean, renewable energy. Beyond the technical and economic challenges of wind energy development are environmental issues that may restrict its growth. Avian fatalities due to collisions with rotating turbine blades are a leading concern and there is considerable uncertainty surrounding avian collision risk at wind facilities. This uncertainty is not reflected in many models currently used to predict the avian fatalities that would result from proposed wind developments. We introduce a method to predict fatalities at wind facilities, based on pre-construction monitoring. Our method can directly incorporate uncertainty into the estimates of avian fatalities and can be updated if information on the true number of fatalities becomes available from post-construction carcass monitoring. Our model considers only three parameters: hazardous footprint, bird exposure to turbines and collision probability. By using a Bayesian analytical framework we account for uncertainties in these values, which are then reflected in our predictions and can be reduced through subsequent data collection. The simplicity of our approach makes it accessible to ecologists concerned with the impact of wind development, as well as to managers, policy makers and industry interested in its implementation in real-world decision contexts. We demonstrate the utility of our method by predicting golden eagle (Aquila chrysaetos fatalities at a wind installation in the United States. Using pre-construction data, we predicted 7.48 eagle fatalities year-1 (95% CI: (1.1, 19.81. The U.S. Fish and Wildlife Service uses the 80th quantile (11.0 eagle fatalities year-1 in their permitting process to ensure there is only a 20% chance a wind facility exceeds the authorized fatalities. Once data were available from two-years of post-construction monitoring, we updated the fatality estimate to 4.8 eagle fatalities year-1 (95% CI: (1.76, 9.4; 80th

  11. The fault-tree compiler

    Science.gov (United States)

    Martensen, Anna L.; Butler, Ricky W.

    1987-01-01

    The Fault Tree Compiler Program is a new reliability tool used to predict the top event probability for a fault tree. Five different gate types are allowed in the fault tree: AND, OR, EXCLUSIVE OR, INVERT, and M OF N gates. The high level input language is easy to understand and use when describing the system tree. In addition, the use of the hierarchical fault tree capability can simplify the tree description and decrease program execution time. The current solution technique provides an answer precise (within the limits of double precision floating point arithmetic) to the five digits in the answer. The user may vary one failure rate or failure probability over a range of values and plot the results for sensitivity analyses. The solution technique is implemented in FORTRAN; the remaining program code is implemented in Pascal. The program is written to run on a Digital Corporation VAX with the VMS operation system.

  12. Cell boundary fault detection system

    Science.gov (United States)

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2009-05-05

    A method determines a nodal fault along the boundary, or face, of a computing cell. Nodes on adjacent cell boundaries communicate with each other, and the communications are analyzed to determine if a node or connection is faulty.

  13. Fault Tolerant External Memory Algorithms

    DEFF Research Database (Denmark)

    Jørgensen, Allan Grønlund; Brodal, Gerth Stølting; Mølhave, Thomas

    2009-01-01

    Algorithms dealing with massive data sets are usually designed for I/O-efficiency, often captured by the I/O model by Aggarwal and Vitter. Another aspect of dealing with massive data is how to deal with memory faults, e.g. captured by the adversary based faulty memory RAM by Finocchi and Italiano....... However, current fault tolerant algorithms do not scale beyond the internal memory. In this paper we investigate for the first time the connection between I/O-efficiency in the I/O model and fault tolerance in the faulty memory RAM, and we assume that both memory and disk are unreliable. We show a lower...... bound on the number of I/Os required for any deterministic dictionary that is resilient to memory faults. We design a static and a dynamic deterministic dictionary with optimal query performance as well as an optimal sorting algorithm and an optimal priority queue. Finally, we consider scenarios where...

  14. Kullback-Leibler Divergence for fault estimation and isolation : Application to Gamma distributed data

    Science.gov (United States)

    Delpha, Claude; Diallo, Demba; Youssef, Abdulrahman

    2017-09-01

    In this paper we develop a fault detection, isolation and estimation method based on data-driven approach. Data-driven methods are effective for feature extraction and feature analysis using statistical techniques. In the proposal, the Principal Component Analysis (PCA) method is used to extract the features and to reduce the data dimension. Then, the Kullback-Leibler Divergence (KLD) is used to detect the fault occurrence by comparing the Probability Density Function of the latent scores. To estimate the fault amplitude in case of Gamma distributed data, we have developed an analytical model that links the KLD to the fault severity, including the environmental noise conditions. In the Principal Component Analysis framework, the proposed model of the KLD has been analysed and compared to an estimated value of the KLD using the Monte-Carlo estimator. The results show that for incipient faults ( 40 dB), the fault amplitude estimation is accurate enough with a relative error less than 1%. The proposed approach is experimentally verified with vibration signals used for monitoring bearings in electrical machines.

  15. Diagnosis and fault-tolerant control

    CERN Document Server

    Blanke, Mogens; Lunze, Jan; Staroswiecki, Marcel

    2016-01-01

    Fault-tolerant control aims at a gradual shutdown response in automated systems when faults occur. It satisfies the industrial demand for enhanced availability and safety, in contrast to traditional reactions to faults, which bring about sudden shutdowns and loss of availability. The book presents effective model-based analysis and design methods for fault diagnosis and fault-tolerant control. Architectural and structural models are used to analyse the propagation of the fault through the process, to test the fault detectability and to find the redundancies in the process that can be used to ensure fault tolerance. It also introduces design methods suitable for diagnostic systems and fault-tolerant controllers for continuous processes that are described by analytical models of discrete-event systems represented by automata. The book is suitable for engineering students, engineers in industry and researchers who wish to get an overview of the variety of approaches to process diagnosis and fault-tolerant contro...

  16. An architecture for fault tolerant controllers

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob

    2005-01-01

    degradation in the sense of guaranteed degraded performance. A number of fault diagnosis problems, fault tolerant control problems, and feedback control with fault rejection problems are formulated/considered, mainly from a fault modeling point of view. The method is illustrated on a servo example including......A general architecture for fault tolerant control is proposed. The architecture is based on the (primary) YJBK parameterization of all stabilizing compensators and uses the dual YJBK parameterization to quantify the performance of the fault tolerant system. The approach suggested can be applied...... for additive faults, parametric faults, and for system structural changes. The modeling for each of these fault classes is described. The method allows to design for passive as well as for active fault handling. Also, the related design method can be fitted either to guarantee stability or to achieve graceful...

  17. Static Decoupling in fault detection

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    1998-01-01

    An algebraic approach is given for a design of a static residual weighting factor in connection with fault detection. A complete parameterization is given of the weighting factor which will minimize a given performance index......An algebraic approach is given for a design of a static residual weighting factor in connection with fault detection. A complete parameterization is given of the weighting factor which will minimize a given performance index...

  18. Fault-tolerant rotary actuator

    Science.gov (United States)

    Tesar, Delbert

    2006-10-17

    A fault-tolerant actuator module, in a single containment shell, containing two actuator subsystems that are either asymmetrically or symmetrically laid out is provided. Fault tolerance in the actuators of the present invention is achieved by the employment of dual sets of equal resources. Dual resources are integrated into single modules, with each having the external appearance and functionality of a single set of resources.

  19. Recognition of Active Faults and Stress Field

    Science.gov (United States)

    Azuma, T.

    2012-12-01

    Around the plate-boundary region, the directions of maximum and minimum stress related to the plate motion is one of the key for the recognition of active faults. For example, it is typical idea that there are many N-S trading reverse faults, NE-SW and NW-SE trending strike slip faults and less normal faults (only near volcanoes) in Japan, where the compressional stress with E-W direction is dominant caused by the motion of the subduction of the Pacific Plate beneath the North American Plate. After the 2011 Tohoku earthquake (Mj 9.0), however, many earthquakes with the mechanism of the normal fault type occurred in the coastal region of the northern-east Japan. On 11th April 2011, the Fukushima Hamadori Earthquake (Mj 7.0) occurred accompanying surface faults along two faults, the Idosawa fault and the Yunotake fault, that recognized as active faults by the Research Group for Active Fault of Japan (1980, 1991). It impacted on active fault study by the reason of not only the appearance of two traces of significant surface faults with maximum displacement up to 2.1 m, but also the reactivation of the normal faults under the E-W compressional stress field. When we identify the active faults, it is one of the key whether the direction of slip on the fault consists with the stress field in that area or not. And there is a technique to recognized whether the fault is active or not by using the data of the direction of stress in the field and the geometry of the fault plane. Though it is useful for the fault in the rock without overlain Quaternary deposits, we should care that the active faults may react caused by the temporal stress condition after the generation of large earthquakes.

  20. The mechanics of gravity-driven faulting

    OpenAIRE

    L. Barrows; V. Barrows

    2010-01-01

    Faulting can result from either of two different mechanisms. These involve fundamentally different energetics. In elastic rebound, locked-in elastic strain energy is transformed into the earthquake (seismic waves plus work done in the fault zone). In force-driven faulting, the forces that create the stress on the fault supply work or energy to the faulting process. Half of this energy is transformed into the earthquake and half goes into an increase in locked-in elastic strain. In elastic reb...

  1. Normal fault earthquakes or graviquakes

    Science.gov (United States)

    Doglioni, C.; Carminati, E.; Petricca, P.; Riguzzi, F.

    2015-01-01

    Earthquakes are dissipation of energy throughout elastic waves. Canonically is the elastic energy accumulated during the interseismic period. However, in crustal extensional settings, gravity is the main energy source for hangingwall fault collapsing. Gravitational potential is about 100 times larger than the observed magnitude, far more than enough to explain the earthquake. Therefore, normal faults have a different mechanism of energy accumulation and dissipation (graviquakes) with respect to other tectonic settings (strike-slip and contractional), where elastic energy allows motion even against gravity. The bigger the involved volume, the larger is their magnitude. The steeper the normal fault, the larger is the vertical displacement and the larger is the seismic energy released. Normal faults activate preferentially at about 60° but they can be shallower in low friction rocks. In low static friction rocks, the fault may partly creep dissipating gravitational energy without releasing great amount of seismic energy. The maximum volume involved by graviquakes is smaller than the other tectonic settings, being the activated fault at most about three times the hypocentre depth, explaining their higher b-value and the lower magnitude of the largest recorded events. Having different phenomenology, graviquakes show peculiar precursors. PMID:26169163

  2. RECENT GEODYNAMICS OF FAULT ZONES: FAULTING IN REAL TIME SCALE

    Directory of Open Access Journals (Sweden)

    Yu. O. Kuzmin

    2015-09-01

    Full Text Available Recent deformation processes taking place in real time are analyzed on the basis of data on fault zones which were collected by long-term detailed geodetic survey studies with application of field methods and satellite monitoring.A new category of recent crustal movements is described and termed as parametrically induced tectonic strain in fault zones. It is shown that in the fault zones located in seismically active and aseismic regions, super intensive displacements of the crust (5 to 7 cm per year, i.e. (5 to 7·10–5 per year occur due to very small external impacts of natural or technogenic / industrial origin.The spatial discreteness of anomalous deformation processes is established along the strike of the regional Rechitsky fault in the Pripyat basin. It is concluded that recent anomalous activity of the fault zones needs to be taken into account in defining regional regularities of geodynamic processes on the basis of real-time measurements.The paper presents results of analyses of data collected by long-term (20 to 50 years geodetic surveys in highly seismically active regions of Kopetdag, Kamchatka and California. It is evidenced by instrumental geodetic measurements of recent vertical and horizontal displacements in fault zones that deformations are ‘paradoxically’ deviating from the inherited movements of the past geological periods.In terms of the recent geodynamics, the ‘paradoxes’ of high and low strain velocities are related to a reliable empirical fact of the presence of extremely high local velocities of deformations in the fault zones (about 10–5 per year and above, which take place at the background of slow regional deformations which velocities are lower by the order of 2 to 3. Very low average annual velocities of horizontal deformation are recorded in the seismic regions of Kopetdag and Kamchatka and in the San Andreas fault zone; they amount to only 3 to 5 amplitudes of the earth tidal deformations per year.A ‘fault

  3. Density matrix quantum Monte Carlo

    CERN Document Server

    Blunt, N S; Spencer, J S; Foulkes, W M C

    2013-01-01

    This paper describes a quantum Monte Carlo method capable of sampling the full density matrix of a many-particle system, thus granting access to arbitrary reduced density matrices and allowing expectation values of complicated non-local operators to be evaluated easily. The direct sampling of the density matrix also raises the possibility of calculating previously inaccessible entanglement measures. The algorithm closely resembles the recently introduced full configuration interaction quantum Monte Carlo method, but works all the way from infinite to zero temperature. We explain the theory underlying the method, describe the algorithm, and introduce an importance-sampling procedure to improve the stochastic efficiency. To demonstrate the potential of our approach, the energy and staggered magnetization of the isotropic antiferromagnetic Heisenberg model on small lattices and the concurrence of one-dimensional spin rings are compared to exact or well-established results. Finally, the nature of the sign problem...

  4. Efficient kinetic Monte Carlo simulation

    Science.gov (United States)

    Schulze, Tim P.

    2008-02-01

    This paper concerns kinetic Monte Carlo (KMC) algorithms that have a single-event execution time independent of the system size. Two methods are presented—one that combines the use of inverted-list data structures with rejection Monte Carlo and a second that combines inverted lists with the Marsaglia-Norman-Cannon algorithm. The resulting algorithms apply to models with rates that are determined by the local environment but are otherwise arbitrary, time-dependent and spatially heterogeneous. While especially useful for crystal growth simulation, the algorithms are presented from the point of view that KMC is the numerical task of simulating a single realization of a Markov process, allowing application to a broad range of areas where heterogeneous random walks are the dominate simulation cost.

  5. Adaptive Multilevel Monte Carlo Simulation

    KAUST Repository

    Hoel, H

    2011-08-23

    This work generalizes a multilevel forward Euler Monte Carlo method introduced in Michael B. Giles. (Michael Giles. Oper. Res. 56(3):607–617, 2008.) for the approximation of expected values depending on the solution to an Itô stochastic differential equation. The work (Michael Giles. Oper. Res. 56(3):607– 617, 2008.) proposed and analyzed a forward Euler multilevelMonte Carlo method based on a hierarchy of uniform time discretizations and control variates to reduce the computational effort required by a standard, single level, Forward Euler Monte Carlo method. This work introduces an adaptive hierarchy of non uniform time discretizations, generated by an adaptive algorithmintroduced in (AnnaDzougoutov et al. Raùl Tempone. Adaptive Monte Carlo algorithms for stopped diffusion. In Multiscale methods in science and engineering, volume 44 of Lect. Notes Comput. Sci. Eng., pages 59–88. Springer, Berlin, 2005; Kyoung-Sook Moon et al. Stoch. Anal. Appl. 23(3):511–558, 2005; Kyoung-Sook Moon et al. An adaptive algorithm for ordinary, stochastic and partial differential equations. In Recent advances in adaptive computation, volume 383 of Contemp. Math., pages 325–343. Amer. Math. Soc., Providence, RI, 2005.). This form of the adaptive algorithm generates stochastic, path dependent, time steps and is based on a posteriori error expansions first developed in (Anders Szepessy et al. Comm. Pure Appl. Math. 54(10):1169– 1214, 2001). Our numerical results for a stopped diffusion problem, exhibit savings in the computational cost to achieve an accuracy of ϑ(TOL),from(TOL−3), from using a single level version of the adaptive algorithm to ϑ(((TOL−1)log(TOL))2).

  6. Active Fault Research (1996); Katsudanso kenkyu (1996)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-25

    This is a general collection of papers dealing with the research of active faults. In Japan, since very heavy damage was produced by the Hyogoken-Nambu earthquake of January, 1955, discussion of active faults has promptly grown very active. In relation to the said earthquake, detailed maps of earthquake faults that emerged in the same, trench investigations of the Awajishima surface fault rupture related to the same, and the circumstances of the southern and northern ends of the Nojima earthquake fault are reported. Discussion is made about the re-examination of precaution faults and the possibility of the presence of C-class active faults, dealing with the entirety of Japan. Itemized discussion covers the fossil liquefaction observed on the campus of Hokkaido University, fault outcrop at the geological boundary west of Hanamaki and at the western edge of the Kitakami lowland, morphology at the Median Tectonic Line active fault system Iyo fault, fault outcrop discovered at the Iwakuni active fault system Otake fault, and the Kokura Higashi fault and the topography surrounding it (northern part of Kyushu) are introduced. Furthermore, there are reports on the F1 fault and neotectonics in the Tan-Lu fracture zone in the Linyi area, Shandong Province, eastern part of China.

  7. Slope instability mapping around L'Aquila (Abruzzo, Italy) with Persistent Scatterers Interferometry from ERS, ENVISAT and RADARSAT datasets

    Science.gov (United States)

    Righini, Gaia; Del Conte, Sara; Cigna, Francesca; Casagli, Nicola

    2010-05-01

    In the last decade Persistent Scatterers Interferometry (PSI) was used in natural hazards investigations with significant results and it is considered a helpful tool in ground deformations detection and mapping (Berardino et. al., 2003; Colesanti et al., 2003; Colesanti & Wasowski, 2006; Hilley et al., 2004). In this work results of PSI processing were interpreted after the main seismic shock that affected the Abruzzo region (Central Italy) on 6th of April 2009, in order to carry out a slope instability mapping according to the requirement of National Department of Civil Protection and in the framework of the Landslides thematic services of the EU FP7 project ‘SAFER' (Services and Applications For Emergency Response - Grant Agreement n° 218802). The area of interest was chosen in almost 460 km2 around L'Aquila according the highest probability of reactivations of landslides which depends on the local geological conditions, on the epicenter location and on other seismic parameters (Keefer, 1984). The radar images datasets were collected in order to provide estimates of the mean yearly velocity referred to two distinct time intervals: historic ERS (1992-2000) and recent ENVISAT (2002-2009), RADARSAT (2003-2009); the ERS and RADARSAT images were processed by Tele-Rilevamento Europa (TRE) using PS-InSAR(TM) technique, while the ENVISAT images were processed by e-GEOS using PSP-DIFSAR technique. A pre-existing landslide inventory map was updated through the integration of conventional photo interpretation and the radar-interpretation chain, as defined by Farina et al. (2008) and reported in literature (Farina et al. 2006, Meisina et al. 2007, Pancioli et al., 2008; Righini et al., 2008, Casagli et al., 2008, Herrera et al., 2009). The data were analyzed and interpreted in Geographic Information System (GIS) environment. Main updates of the pre-existing landslides are focusing on the identification of new landslides, modification of boundaries through the spatial

  8. The frictional properties of faults at shallow depths: implications for rupture propagation.

    Science.gov (United States)

    De Paola, Nicola; Bullock, Rachael; Unwin, Rachel; Murray, Rosanne; Stillings, Mark; Holdsworth, Robert

    2015-04-01

    Most synoptic models of faults assume the presence of a shallow stable, velocity-strengthening aseismic region due to the presence of incohesive gouges, poorly lithified continental sediments (continental faults) and phyllosilicate-rich rocks (accretionary prisms at subduction zones). The near-surface portions of faults are therefore viewed as effective energy sinks with the potential to arrest/slow down the propagation of earthquakes, preventing them from reaching the surface. However, recent events, such as the 2009 Mw 6.3 L'Aquila and 2011 Mw 9.0 Tohoku-Oki earthquakes, have demonstrated that moderate/large co-seismic ruptures can propagate to the surface causing vast damage and destructive tsunamis. In order to better understand rupture propagation at shallow depths, we investigated the frictional properties of a range of bedrock lithologies, typical of the oceanic (gabbros) and continental crusts (granite, limestone), together with phyllosilicate-bearing lithologies typical of subduction zones and continental sedimentary deposits. Laboratory experiments have been performed in a low to high velocity rotary shear apparatus, on granular materials with grainsize up to 200 μm, under dry, water- and brine-saturated conditions, at slip rates ranging from 10 μm/s up to 1 m/s, with normal loads up to 18 MPa and displacements up to 1 m. Velocity step experiments performed at sub-seismic slip rates (10-100 μm/s) on dry, water- and brine-saturated granite and calcite rocks show that velocity strengthening behaviour evolves to velocity-neutral/-weakening behaviour due to slip localization attained after critical displacements of a few tens to hundreds of mm. The critical displacement value is inversely proportional to the applied normal load. Dry, water- and brine-saturated gabbros show velocity-weakening behaviour and slip localization regardless of the displacement attained and applied normal load. Dry, water- and brine-saturated phyllosilicate-rich gouges show

  9. A methodological non destructive approach for the conservation or structural repair of the Medioeval stone pillars of the Basilica of Santa Maria di Collemaggio in L'Aquila.

    Science.gov (United States)

    Raimondo, Quaresima; Elena, Antonacci; Felice, Fusco; Antonio, Filippone; Lorenzo, Fanale; Galeota, Dante

    2015-04-01

    The Medioeval Basilica of Santa Maria of Collemaggio in L'Aquila (XII century) due to the history and the election of Pope Celestino V, the Celestine Pardon, as well as to the artistic features, has a great religious and historic relevance. The whole Basilica was severely damaged during the earthquake of April 2009 and in particular the transetto zone with the cupola collapsed and ruined completely. By means of the project "Starting Afresh with Collemaggio" the Italian company Eni signs a memorandum of understanding with the city of L'Aquila for the restoration of the monument and of Collemaggio site. For this reason a wide and complex multidisciplinary diagnostic campaign was carried out in order to prepare the final design. A specific aspect concerned the diagnosis of the fourteen octagonal pillars of the central nave in terms of state of conservation and structural behavior. Each pillar consists, more or less, in forty big squared blocks of different local carbonatic stones. The diagnosis was preliminary executed by means of visual checks and mapping of the materials and of the structural damages. Subsequently non destructrutive ultrasonic and endoscopic techniques was carried out. The ultrasonic data were elaborated in order to obtain distribution maps of the velocity in the plane sections. To understanding the compressive strength of the stones and the resistance of the pillars, according to structural instances, destructive, compressive tests, and non destructive, ultrasonic and sclerometric measures, were performed of carbonatic blocks quarried in the sourroundings of L'Aquila. The compressive destructive results, inclusive of ultrasonic and sclerometric results, were compared with those non destructive obtained on the stone blocks of the pillars. The results allow to establish that three typologies of carbonatic stone were used. In many cases the surface of the stone, due to previously heartquake, was replaced with thick pieces of different stones

  10. Fault geometry and earthquake mechanics

    Directory of Open Access Journals (Sweden)

    D. J. Andrews

    1994-06-01

    Full Text Available Earthquake mechanics may be determined by the geometry of a fault system. Slip on a fractal branching fault surface can explain: 1 regeneration of stress irregularities in an earthquake; 2 the concentration of stress drop in an earthquake into asperities; 3 starting and stopping of earthquake slip at fault junctions, and 4 self-similar scaling of earthquakes. Slip at fault junctions provides a natural realization of barrier and asperity models without appealing to variations of fault strength. Fault systems are observed to have a branching fractal structure, and slip may occur at many fault junctions in an earthquake. Consider the mechanics of slip at one fault junction. In order to avoid a stress singularity of order 1/r, an intersection of faults must be a triple junction and the Burgers vectors on the three fault segments at the junction must sum to zero. In other words, to lowest order the deformation consists of rigid block displacement, which ensures that the local stress due to the dislocations is zero. The elastic dislocation solution, however, ignores the fact that the configuration of the blocks changes at the scale of the displacement. A volume change occurs at the junction; either a void opens or intense local deformation is required to avoid material overlap. The volume change is proportional to the product of the slip increment and the total slip since the formation of the junction. Energy absorbed at the junction, equal to confining pressure times the volume change, is not large enongh to prevent slip at a new junction. The ratio of energy absorbed at a new junction to elastic energy released in an earthquake is no larger than P/µ where P is confining pressure and µ is the shear modulus. At a depth of 10 km this dimensionless ratio has th value P/µ= 0.01. As slip accumulates at a fault junction in a number of earthquakes, the fault segments are displaced such that they no longer meet at a single point. For this reason the

  11. Fault Management Guiding Principles

    Science.gov (United States)

    Newhouse, Marilyn E.; Friberg, Kenneth H.; Fesq, Lorraine; Barley, Bryan

    2011-01-01

    Regardless of the mission type: deep space or low Earth orbit, robotic or human spaceflight, Fault Management (FM) is a critical aspect of NASA space missions. As the complexity of space missions grows, the complexity of supporting FM systems increase in turn. Data on recent NASA missions show that development of FM capabilities is a common driver for significant cost overruns late in the project development cycle. Efforts to understand the drivers behind these cost overruns, spearheaded by NASA's Science Mission Directorate (SMD), indicate that they are primarily caused by the growing complexity of FM systems and the lack of maturity of FM as an engineering discipline. NASA can and does develop FM systems that effectively protect mission functionality and assets. The cost growth results from a lack of FM planning and emphasis by project management, as well the maturity of FM as an engineering discipline, which lags behind the maturity of other engineering disciplines. As a step towards controlling the cost growth associated with FM development, SMD has commissioned a multi-institution team to develop a practitioner's handbook representing best practices for the end-to-end processes involved in engineering FM systems. While currently concentrating primarily on FM for science missions, the expectation is that this handbook will grow into a NASA-wide handbook, serving as a companion to the NASA Systems Engineering Handbook. This paper presents a snapshot of the principles that have been identified to guide FM development from cradle to grave. The principles range from considerations for integrating FM into the project and SE organizational structure, the relationship between FM designs and mission risk, and the use of the various tools of FM (e.g., redundancy) to meet the FM goal of protecting mission functionality and assets.

  12. Fault Management Guiding Principles

    Science.gov (United States)

    Newhouse, Marilyn E.; Friberg, Kenneth H.; Fesq, Lorraine; Barley, Bryan

    2011-01-01

    Regardless of the mission type: deep space or low Earth orbit, robotic or human spaceflight, Fault Management (FM) is a critical aspect of NASA space missions. As the complexity of space missions grows, the complexity of supporting FM systems increase in turn. Data on recent NASA missions show that development of FM capabilities is a common driver for significant cost overruns late in the project development cycle. Efforts to understand the drivers behind these cost overruns, spearheaded by NASA's Science Mission Directorate (SMD), indicate that they are primarily caused by the growing complexity of FM systems and the lack of maturity of FM as an engineering discipline. NASA can and does develop FM systems that effectively protect mission functionality and assets. The cost growth results from a lack of FM planning and emphasis by project management, as well the maturity of FM as an engineering discipline, which lags behind the maturity of other engineering disciplines. As a step towards controlling the cost growth associated with FM development, SMD has commissioned a multi-institution team to develop a practitioner's handbook representing best practices for the end-to-end processes involved in engineering FM systems. While currently concentrating primarily on FM for science missions, the expectation is that this handbook will grow into a NASA-wide handbook, serving as a companion to the NASA Systems Engineering Handbook. This paper presents a snapshot of the principles that have been identified to guide FM development from cradle to grave. The principles range from considerations for integrating FM into the project and SE organizational structure, the relationship between FM designs and mission risk, and the use of the various tools of FM (e.g., redundancy) to meet the FM goal of protecting mission functionality and assets.

  13. Fault estimation - A standard problem approach

    DEFF Research Database (Denmark)

    Stoustrup, J.; Niemann, Hans Henrik

    2002-01-01

    This paper presents a range of optimization based approaches to fault diagnosis. A variety of fault diagnosis problems are reformulated in the so-called standard problem set-up introduced in the literature on robust control. Once the standard problem formulations are given, the fault diagnosis pr...... problems can be solved by standard optimization techniques. The proposed methods include (1) fault diagnosis (fault estimation, (FE)) for systems with model uncertainties; FE for systems with parametric faults, and FE for a class of nonlinear systems. Copyright......This paper presents a range of optimization based approaches to fault diagnosis. A variety of fault diagnosis problems are reformulated in the so-called standard problem set-up introduced in the literature on robust control. Once the standard problem formulations are given, the fault diagnosis...

  14. Fault detection and isolation for complex system

    Science.gov (United States)

    Jing, Chan Shi; Bayuaji, Luhur; Samad, R.; Mustafa, M.; Abdullah, N. R. H.; Zain, Z. M.; Pebrianti, Dwi

    2017-07-01

    Fault Detection and Isolation (FDI) is a method to monitor, identify, and pinpoint the type and location of system fault in a complex multiple input multiple output (MIMO) non-linear system. A two wheel robot is used as a complex system in this study. The aim of the research is to construct and design a Fault Detection and Isolation algorithm. The proposed method for the fault identification is using hybrid technique that combines Kalman filter and Artificial Neural Network (ANN). The Kalman filter is able to recognize the data from the sensors of the system and indicate the fault of the system in the sensor reading. Error prediction is based on the fault magnitude and the time occurrence of fault. Additionally, Artificial Neural Network (ANN) is another algorithm used to determine the type of fault and isolate the fault in the system.

  15. Foreshocks and short-term hazard assessment of large earthquakes using complex networks: the case of the 2009 L'Aquila earthquake

    Science.gov (United States)

    Daskalaki, Eleni; Spiliotis, Konstantinos; Siettos, Constantinos; Minadakis, Georgios; Papadopoulos, Gerassimos A.

    2016-08-01

    The monitoring of statistical network properties could be useful for the short-term hazard assessment of the occurrence of mainshocks in the presence of foreshocks. Using successive connections between events acquired from the earthquake catalog of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) for the case of the L'Aquila (Italy) mainshock (Mw = 6.3) of 6 April 2009, we provide evidence that network measures, both global (average clustering coefficient, small-world index) and local (betweenness centrality) ones, could potentially be exploited for forecasting purposes both in time and space. Our results reveal statistically significant increases in the topological measures and a nucleation of the betweenness centrality around the location of the epicenter about 2 months before the mainshock. The results of the analysis are robust even when considering either large or off-centered the main event space windows.

  16. 金雕肾脏的组织学观察%An Observation on the Histology of the Kidney in Aquila chrysaetos

    Institute of Scientific and Technical Information of China (English)

    米志平

    2010-01-01

    利用生物显微技术观察了金雕Aquila chrysaetos肾脏的组织结构.结果表明,金雕肾实质由许多肾小叶构成,每个肾小叶可分为皮质和髓质两部分.肾单位由一个肾小体和一条与其相连的肾小管构成.肾小体由肾小囊和肾小球组成.肾小管分为近曲小管、髓袢、远曲小管和连接小管.集合管分为小叶周集合小管和髓质集合管两部分.具有发达的极周细胞.

  17. Application of fault current limiters

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, A.

    2007-11-30

    This report presents the results of a study commissioned by the Department for Business, Enterprise and Industry (BERR; formerly the Department of Trade and Industry) into the application of fault current limiters in the UK. The study reviewed the current state of fault current limiter (FCL) technology and regulatory position in relation to all types of current limiters. It identified significant research and development work with respect to medium voltage FCLs and a move to high voltage. Appropriate FCL technologies being developed include: solid state breakers; superconducting FCLs (including superconducting transformers); magnetic FCLs; and active network controllers. Commercialisation of these products depends on successful field tests and experience, plus material development in the case of high temperature superconducting FCL technologies. The report describes FCL techniques, the current state of FCL technologies, practical applications and future outlook for FCL technologies, distribution fault level analysis and an outline methodology for assessing the materiality of the fault level problem. A roadmap is presented that provides an 'action agenda' to advance the fault level issues associated with low carbon networks.

  18. Fault Isolation for Shipboard Decision Support

    DEFF Research Database (Denmark)

    Lajic, Zoran; Blanke, Mogens; Nielsen, Ulrik Dam

    2010-01-01

    Fault detection and fault isolation for in-service decision support systems for marine surface vehicles will be presented in this paper. The stochastic wave elevation and the associated ship responses are modeled in the frequency domain. The paper takes as an example fault isolation of a containe......Fault detection and fault isolation for in-service decision support systems for marine surface vehicles will be presented in this paper. The stochastic wave elevation and the associated ship responses are modeled in the frequency domain. The paper takes as an example fault isolation...

  19. Probabilistic fault localization with sliding windows

    Institute of Scientific and Technical Information of China (English)

    ZHANG Cheng; LIAO JianXin; LI TongHong; ZHU XiaoMin

    2012-01-01

    Fault localization is a central element in network fault management.This paper takes a weighted bipartite graph as a fault propagation model and presents a heuristic fault localization algorithm based on the idea of incremental coverage,which is resilient to inaccurate fault propagation model and the noisy environment.Furthermore,a sliding window mechanism is proposed to tackle the inaccuracy of this algorithm in the presence of improper time windows.As shown in the simulation study,our scheme achieves higher detection rate and lower false positive rate in the noisy environment as well as in the presence of inaccurate windows,than current fault localization algorithms.

  20. Identification of Transient and Permanent Faults

    Institute of Scientific and Technical Information of China (English)

    李幼仪; 董新洲; 孙元章

    2003-01-01

    A new algorithm was developed for arcing fault detection based on high-frequency current transients analyzed with wavelet transforms to avoid automatic reclosing on permanent faults. The characteristics of arc currents during transient faults were investigated. The current curves of transient and permanent faults are quite similar since current variation from the fault arc is much less than the voltage variation. However, the fault current details are quite different because of the arc extinguishing and reigniting. Dyadic wavelet transforms were used to identify the current variation since wavelet transform has time-frequency localization ability. Many electric magnetic transient program (EMTP) simulations have verified the feasibility of the algorithm.

  1. Diagnosis and Fault-tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Kinnaert, Michel; Lunze, Jan

    The book presents effective model-based analysis and design methods for fault diagnosis and fault-tolerant control. Architectural and structural models are used to analyse the propagation of the fault through the process, to test the fault detectability and to find the redundancies in the process...... that can be used to ensure fault tolerance. Design methods for diagnostic systems and fault-tolerant controllers are presented for processes that are described by analytical models, by discrete-event models or that can be dealt with as quantised systems. Four case studies on pilot processes show......-tolerant control....

  2. Fault estimation - A standard problem approach

    DEFF Research Database (Denmark)

    Stoustrup, J.; Niemann, Hans Henrik

    2002-01-01

    This paper presents a range of optimization based approaches to fault diagnosis. A variety of fault diagnosis problems are reformulated in the so-called standard problem set-up introduced in the literature on robust control. Once the standard problem formulations are given, the fault diagnosis...... problems can be solved by standard optimization techniques. The proposed methods include (1) fault diagnosis (fault estimation, (FE)) for systems with model uncertainties; FE for systems with parametric faults, and FE for a class of nonlinear systems. Copyright...

  3. TRANSMISSION LINE FAULT ANALYSIS USING WAVELET THEORY

    Directory of Open Access Journals (Sweden)

    Ravindra Malkar

    2012-06-01

    Full Text Available This paper describes a Wavelet transform technique to analyze power system disturbance such as transmission line faults with Biorthogonal and Haar wavelets. In this work, wavelet transform based approach,which is used to detect transmission line faults, is proposed. The coefficient of discrete approximation of the dyadic wavelet transform with different wavelets are used to be an index for transmission line fault detection and faulted – phase selection and select which wavelet is suitable for this application. MATLAB/Simulation is used to generate fault signals. Simulation results reveal that the performance of the proposed fault detection indicator is promising and easy to implement for computer relaying application.

  4. Monte Carlo approach to turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Dueben, P.; Homeier, D.; Muenster, G. [Muenster Univ. (Germany). Inst. fuer Theoretische Physik; Jansen, K. [DESY, Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Mesterhazy, D. [Humboldt Univ., Berlin (Germany). Inst. fuer Physik

    2009-11-15

    The behavior of the one-dimensional random-force-driven Burgers equation is investigated in the path integral formalism on a discrete space-time lattice. We show that by means of Monte Carlo methods one may evaluate observables, such as structure functions, as ensemble averages over different field realizations. The regularization of shock solutions to the zero-viscosity limit (Hopf-equation) eventually leads to constraints on lattice parameters required for the stability of the simulations. Insight into the formation of localized structures (shocks) and their dynamics is obtained. (orig.)

  5. Fault-tolerant Supervisory Control

    DEFF Research Database (Denmark)

    Izadi-Zamanabadi, Roozbeh

    of this work has been to develop and employ concepts and methods that are suitable for use in different automation processes, with applicability in various industrial fields. The requirements for high productivity and quality has resulted in employing additional instrumentation and use of more sophisticated...... could be increased through enhancing control systems' ability to on-line perform fault detection and reconfiguration when a fault occurs and before a safety system shuts-down the entire process. The main contributions of this research effort are development and experimentation with methodologies......, is extended to cope with the important reconfiguration problem. In order to enable a designer to acquire knowledge about reconfiguration possibilities, the structural analysis method is added as an extension to the existing methodology. This extension builds upon the earlier method where fault propagation...

  6. Transient Faults in Computer Systems

    Science.gov (United States)

    Masson, Gerald M.

    1993-01-01

    A powerful technique particularly appropriate for the detection of errors caused by transient faults in computer systems was developed. The technique can be implemented in either software or hardware; the research conducted thus far primarily considered software implementations. The error detection technique developed has the distinct advantage of having provably complete coverage of all errors caused by transient faults that affect the output produced by the execution of a program. In other words, the technique does not have to be tuned to a particular error model to enhance error coverage. Also, the correctness of the technique can be formally verified. The technique uses time and software redundancy. The foundation for an effective, low-overhead, software-based certification trail approach to real-time error detection resulting from transient fault phenomena was developed.

  7. Monte Carlo techniques in radiation therapy

    CERN Document Server

    Verhaegen, Frank

    2013-01-01

    Modern cancer treatment relies on Monte Carlo simulations to help radiotherapists and clinical physicists better understand and compute radiation dose from imaging devices as well as exploit four-dimensional imaging data. With Monte Carlo-based treatment planning tools now available from commercial vendors, a complete transition to Monte Carlo-based dose calculation methods in radiotherapy could likely take place in the next decade. Monte Carlo Techniques in Radiation Therapy explores the use of Monte Carlo methods for modeling various features of internal and external radiation sources, including light ion beams. The book-the first of its kind-addresses applications of the Monte Carlo particle transport simulation technique in radiation therapy, mainly focusing on external beam radiotherapy and brachytherapy. It presents the mathematical and technical aspects of the methods in particle transport simulations. The book also discusses the modeling of medical linacs and other irradiation devices; issues specific...

  8. InSAR measurements around active faults: creeping Philippine Fault and un-creeping Alpine Fault

    Science.gov (United States)

    Fukushima, Y.

    2013-12-01

    Recently, interferometric synthetic aperture radar (InSAR) time-series analyses have been frequently applied to measure the time-series of small and quasi-steady displacements in wide areas. Large efforts in the methodological developments have been made to pursue higher temporal and spatial resolutions by using frequently acquired SAR images and detecting more pixels that exhibit phase stability. While such a high resolution is indispensable for tracking displacements of man-made and other small-scale structures, it is not necessarily needed and can be unnecessarily computer-intensive for measuring the crustal deformation associated with active faults and volcanic activities. I apply a simple and efficient method to measure the deformation around the Alpine Fault in the South Island of New Zealand, and the Philippine Fault in the Leyte Island. I use a small-baseline subset (SBAS) analysis approach (Berardino, et al., 2002). Generally, the more we average the pixel values, the more coherent the signals are. Considering that, for the deformation around active faults, the spatial resolution can be as coarse as a few hundred meters, we can severely 'multi-look' the interferograms. The two applied cases in this study benefited from this approach; I could obtain the mean velocity maps on practically the entire area without discarding decorrelated areas. The signals could have been only partially obtained by standard persistent scatterer or single-look small-baseline approaches that are much more computer-intensive. In order to further increase the signal detection capability, it is sometimes effective to introduce a processing algorithm adapted to the signal of interest. In an InSAR time-series processing, one usually needs to set the reference point because interferograms are all relative measurements. It is difficult, however, to fix the reference point when one aims to measure long-wavelength deformation signals that span the whole analysis area. This problem can be

  9. Growth of faults in crystalline rock

    Science.gov (United States)

    Martel, S. J.

    2009-04-01

    The growth of faults depends on the coupled interplay of the distribution of slip, fault geometry, the stress field in the host rock, and deformation of the host rock, which commonly is manifest in secondary fracturing. The distribution of slip along a fault depends highly on its structure, the stress perturbation associated with its interaction with nearby faults, and its strength distribution; mechanical analyses indicate that the first two factors are more influential than the third. Slip distribution data typically are discrete, but commonly are described, either explicitly or implicitly, using continuous interpolation schemes. Where the third derivative of a continuous slip profile is discontinuous, the compatibility conditions of strain are violated, and fracturing and perturbations to fault geometry should occur. Discontinuous third derivatives accompany not only piecewise linear functions, but also functions as seemingly benign as cubic splines. The stress distribution and fracture distribution along a fault depends strongly on how the fault grows. Evidence to date indicates that a fault that nucleates along a pre-existing, nearly planar joint or a dike typically develops secondary fractures only near its tipline when the slip is small relative to the fault length. In contrast, stress concentrations and fractures are predicted where a discontinuous or non-planar fault exhibits steps and bends; field observations bear this prediction out. Secondary fracturing influences how faults grow by creating damage zones and by linking originally discontinuous elements into a single fault zone. Field observations of both strike-slip faults and dip-slip faults show that linked segments usually will not be coplanar; elastic stress analyses indicate that this is an inherent tendency of how three-dimensional faults grow. Advances in the data we collect and in the rigor and sophistication of our analyses seem essential to substantially advance our ability to successfully

  10. Approaching Chemical Accuracy with Quantum Monte Carlo

    OpenAIRE

    Petruzielo, Frank R.; Toulouse, Julien; Umrigar, C. J.

    2012-01-01

    International audience; A quantum Monte Carlo study of the atomization energies for the G2 set of molecules is presented. Basis size dependence of diffusion Monte Carlo atomization energies is studied with a single determinant Slater-Jastrow trial wavefunction formed from Hartree-Fock orbitals. With the largest basis set, the mean absolute deviation from experimental atomization energies for the G2 set is 3.0 kcal/mol. Optimizing the orbitals within variational Monte Carlo improves the agreem...

  11. Mean field simulation for Monte Carlo integration

    CERN Document Server

    Del Moral, Pierre

    2013-01-01

    In the last three decades, there has been a dramatic increase in the use of interacting particle methods as a powerful tool in real-world applications of Monte Carlo simulation in computational physics, population biology, computer sciences, and statistical machine learning. Ideally suited to parallel and distributed computation, these advanced particle algorithms include nonlinear interacting jump diffusions; quantum, diffusion, and resampled Monte Carlo methods; Feynman-Kac particle models; genetic and evolutionary algorithms; sequential Monte Carlo methods; adaptive and interacting Marko

  12. Fault-tolerant system for catastrophic faults in AMR sensors

    NARCIS (Netherlands)

    Zambrano Constantini, A.C.; Kerkhoff, Hans G.

    Anisotropic Magnetoresistance angle sensors are widely used in automotive applications considered to be safety-critical applications. Therefore dependability is an important requirement and fault-tolerant strategies must be used to guarantee the correct operation of the sensors even in case of

  13. Monte Carlo Treatment Planning for Advanced Radiotherapy

    DEFF Research Database (Denmark)

    Cronholm, Rickard

    and validation of a Monte Carlo model of a medical linear accelerator (i), converting a CT scan of a patient to a Monte Carlo compliant phantom (ii) and translating the treatment plan parameters (including beam energy, angles of incidence, collimator settings etc) to a Monte Carlo input file (iii). A protocol...... previous algorithms since it uses delineations of structures in order to include and/or exclude certain media in various anatomical regions. This method has the potential to reduce anatomically irrelevant media assignment. In house MATLAB scripts translating the treatment plan parameters to Monte Carlo...

  14. 1-D EQUILIBRIUM DISCRETE DIFFUSION MONTE CARLO

    Energy Technology Data Exchange (ETDEWEB)

    T. EVANS; ET AL

    2000-08-01

    We present a new hybrid Monte Carlo method for 1-D equilibrium diffusion problems in which the radiation field coexists with matter in local thermodynamic equilibrium. This method, the Equilibrium Discrete Diffusion Monte Carlo (EqDDMC) method, combines Monte Carlo particles with spatially discrete diffusion solutions. We verify the EqDDMC method with computational results from three slab problems. The EqDDMC method represents an incremental step toward applying this hybrid methodology to non-equilibrium diffusion, where it could be simultaneously coupled to Monte Carlo transport.

  15. New Insights on the Uncertainties in Finite-Fault Earthquake Source Inversion

    KAUST Repository

    Razafindrakoto, Hoby

    2015-04-01

    New Insights on the Uncertainties in Finite-Fault Earthquake Source Inversion Hoby Njara Tendrisoa Razafindrakoto Earthquake source inversion is a non-linear problem that leads to non-unique solutions. The aim of this dissertation is to understand the uncertainty and reliability in earthquake source inversion, as well as to quantify variability in earthquake rupture models. The source inversion is performed using a Bayesian inference. This technique augments optimization approaches through its ability to image the entire solution space which is consistent with the data and prior information. In this study, the uncertainty related to the choice of source-time function and crustal structure is investigated. Three predefined analytical source-time functions are analyzed; isosceles triangle, Yoffe with acceleration time of 0.1 and 0.3 s. The use of the isosceles triangle as source-time function is found to bias the finite-fault source inversion results. It accelerates the rupture to propagate faster compared to that of the Yoffe function. Moreover, it generates an artificial linear correlation between parameters that does not exist for the Yoffe source-time functions. The effect of inadequate knowledge of Earth’s crustal structure in earthquake rupture models is subsequently investigated. The results show that one-dimensional structure variability leads to parameters resolution changes, with a broadening of the posterior 5 PDFs and shifts in the peak location. These changes in the PDFs of kinematic parameters are associated with the blurring effect of using incorrect Earth structure. As an application to real earthquake, finite-fault source models for the 2009 L’Aquila earthquake are examined using one- and three-dimensional crustal structures. One- dimensional structure is found to degrade the data fitting. However, there is no significant effect on the rupture parameters aside from differences in the spatial slip extension. Stable features are maintained for both

  16. Active fault traces along Bhuj Fault and Katrol Hill Fault, and trenching survey at Wandhay, Kachchh, Gujarat, India

    Indian Academy of Sciences (India)

    Michio Morino; Javed N Malik; Prashant Mishra; Chandrashekhar Bhuiyan; Fumio Kaneko

    2008-06-01

    Several new active fault traces were identified along Katrol Hill Fault (KHF).A new fault (named as Bhuj Fault,BF)that extends into the Bhuj Plain was also identified.These fault traces were identified based on satellite photo interpretation and field survey.Trenches were excavated to identify the paleoseismic events,pattern of faulting and the nature of deformation.New active fault traces were recognized about 1 km north of the topographic boundary between the Katrol Hill and the plain area.The fault exposure along the left bank of Khari River with 10 m wide shear zone in the Mesozoic rocks and showing displacement of the overlying Quaternary deposits is indicative of continued tectonic activity along the ancient fault.The E-W trending active fault traces along the KHF in the western part changes to NE-SW or ENE-WSW near Wandhay village. Trenching survey across a low scarp near Wandhay village reveals three major fault strands F1, F2,and F3.These fault strands displaced the older terrace deposits comprising Sand,Silt and Gravel units along with overlying younger deposits from units 1 to 5 made of gravel,sand and silt. Stratigraphic relationship indicates at least three large magnitude earthquakes along KHF during Late Holocene or recent historic past.

  17. Study on fault induced rock bursts

    Institute of Scientific and Technical Information of China (English)

    LI Zhi-hua; DOU Lin-ming; LU Cai-ping; MU Zong-long; CAO An-ye

    2008-01-01

    In order to study the rules of rock bursts caused by faults by means of mechanical analysis of a roof rock-mass balanced structure and numerical simulation about fault slip destabilization, the effect of coal mining operation on fault plane stresses and slip displacement were studied. The results indicate that the slip displacement sharply increases due to the decrease of normal stress and the increase of shear stress at the fault plane when the working face advances from the footwall to the fault itself, which may induce a fault rock burst. However, this slip displacement will be very small due to the increase of normal stress and the decrease of shear stress when the working face advances from the hanging wall to the fault itself, which results in a very small risk of a fault rock burst.

  18. Evaluating transmission towers potentials during ground faults

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    During ground faults on transmission lines, a number of towers near the fault are likely to acquire high potentials to ground. These tower voltages, if excessive, may present a hazard to humans and animals. This paper presents analytical methods in order to determine the transmission towers potentials during ground faults, for long and short lines. The author developed a global systematic approach to calculate these voltages, which are dependent of a number of factors. Some of the most important factors are: magnitudes of fault currents, fault location with respect to the line terminals, conductor arrangement on the tower and the location of the faulted phase, the ground resistance of the faulted tower, soil resistivity, number, material and size of ground wires. The effects of these factors on the faulted tower voltages have been also examined for different types of power lines.

  19. Finite Fault Database (ANSS ComCat)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A Finite Fault is a modeled representation of the spatial extent, amplitude and duration of fault rupture (slip) of an earthquake, and is generated via the inversion...

  20. Sensor Selection for Aircraft Engine Performance Estimation and Gas Path Fault Diagnostics

    Science.gov (United States)

    Simon, Donald L.; Rinehart, Aidan W.

    2016-01-01

    This paper presents analytical techniques for aiding system designers in making aircraft engine health management sensor selection decisions. The presented techniques, which are based on linear estimation and probability theory, are tailored for gas turbine engine performance estimation and gas path fault diagnostics applications. They enable quantification of the performance estimation and diagnostic accuracy offered by different candidate sensor suites. For performance estimation, sensor selection metrics are presented for two types of estimators including a Kalman filter and a maximum a posteriori estimator. For each type of performance estimator, sensor selection is based on minimizing the theoretical sum of squared estimation errors in health parameters representing performance deterioration in the major rotating modules of the engine. For gas path fault diagnostics, the sensor selection metric is set up to maximize correct classification rate for a diagnostic strategy that performs fault classification by identifying the fault type that most closely matches the observed measurement signature in a weighted least squares sense. Results from the application of the sensor selection metrics to a linear engine model are presented and discussed. Given a baseline sensor suite and a candidate list of optional sensors, an exhaustive search is performed to determine the optimal sensor suites for performance estimation and fault diagnostics. For any given sensor suite, Monte Carlo simulation results are found to exhibit good agreement with theoretical predictions of estimation and diagnostic accuracies.

  1. Error in Monte Carlo, quasi-error in Quasi-Monte Carlo

    OpenAIRE

    Kleiss, R. H. P.; Lazopoulos, A.

    2006-01-01

    While the Quasi-Monte Carlo method of numerical integration achieves smaller integration error than standard Monte Carlo, its use in particle physics phenomenology has been hindered by the abscence of a reliable way to estimate that error. The standard Monte Carlo error estimator relies on the assumption that the points are generated independently of each other and, therefore, fails to account for the error improvement advertised by the Quasi-Monte Carlo method. We advocate the construction o...

  2. Unfolding the procedure of characterizing recorded ultra low frequency, kHZ and MHz electromagnetic anomalies prior to the L'Aquila earthquake as pre-seismic ones. Part II

    CERN Document Server

    Eftaxias, K; Contoyiannis, Y; Papadimitriou, C; Kalimeri, M; Kopanas, J; Antonopoulos, G; Nomicos, C

    2009-01-01

    Ultra low frequency-ULF (1 Hz or lower), kHz and MHz electromagnetic (EM) anomalies were recorded prior to the L'Aquila catastrophic earthquake (EQ) that occurred on April 6, 2009. The detected anomalies followed this temporal scheme. (i) The MHZ EM anomalies were detected on March 26, 2009 and April 2, 2009. The kHz EM anomalies were emerged on April, 4 2009. The ULF EM anomaly was continuously recorded from March 29, 2009 up to April 2, 2009. "Are EQs predictable?" is a question hotly debated in the science community. Its answer begs for another question: "Are there credible EQ precursors?". Despite fairly abundant circumstantial evidence pre-seismic EM signals have not been adequately accepted as real physical quantities. Therefore, the question effortlessly arises as to whether the observed anomalies before the L'Aquila EQ were seismogenic or not. The main goal of this work is to provide some insight into this issue.

  3. AN ANALYSIS OF SOUND FOR FAULT ENGINE

    OpenAIRE

    Suphattharachai Chomphan; Theerathan Kingrattanaset

    2014-01-01

    Various types of faults of the gasoline engine may result in similar symptoms. Sound analysis of engine has been conducted to diagnose the engine faults. This study presents a study of sound analysis of the normal engine and the engine with three different fault conditions. The gasoline engine was our target of this study. The engine sound has been recorded by using a microphone at the engine room for three directions. Three conditions of engine faults including the engine that is not smooth ...

  4. H infinity Integrated Fault Estimation and Fault Tolerant Control of Discrete-time Piecewise Linear Systems

    DEFF Research Database (Denmark)

    Tabatabaeipour, Seyed Mojtaba; Bak, Thomas

    2012-01-01

    In this paper we consider the problem of fault estimation and accommodation for discrete time piecewise linear systems. A robust fault estimator is designed to estimate the fault such that the estimation error converges to zero and H∞ performance of the fault estimation is minimized. Then...

  5. Comment on "Ultra Low Frequency (ULF European multi station magnetic field analysis before and during the 2009 earthquake at L'Aquila regarding regional geotechnical information" by Prattes et al. (2011

    Directory of Open Access Journals (Sweden)

    F. Masci

    2012-05-01

    Full Text Available Prattes et al. (2011 report ULF magnetic anomalous signals claiming them to be possibly precursor of the 6 April 2009 MW = 6.3 L'Aquila earthquake. This comment casts doubts on the possibility that the observed magnetic signatures could have a seismogenic origin by showing that these pre-earthquake signals are actually part of normal global geomagnetic activity.

  6. Geological and geo-seismic aspects of the earthwake in L'Aquila of April 6th 2009 and its implications on the modalities of evaluation of seismic hazard in Italy

    Directory of Open Access Journals (Sweden)

    Antonio Rapolla

    2013-07-01

    Full Text Available Starting with the tragic case of the earthquake in L'Aquila this paper discusses a fundamental aspect of the correct evaluation of the danger (hazard of an area and of a specific urban site, that is, the underestimation of the amplyfying effect of the sites in many developed Italian urgan areas situated in valleys or alluvial plains along with a scarce or incomplete knowledge of the geoseismic parameters of the local underground area.

  7. PALEOSEISMICITY OF QUATERNARY FAULTS NEAR ALBUQUERQUE, NEW MEXICO: The Zia Fault

    OpenAIRE

    McCalpin, James P.

    2001-01-01

    This study continues USGS-funded efforts to assess the activity and earthquake hazard potential of Quaternary faults in the Albuquerque metropolitan region. Our target in 2000 was the Zia fault, a 37 km-long normal fault that trends N-S in northern Llano de Albuquerque (LdA). The Zia fault is one of three major east-dipping normal faults that define the western margin of the Rio Grande rift in the northern Albuquerque basin, the other faults being the Calabacillas fault (to the west of the Zi...

  8. High temperature superconducting fault current limiter

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R. (Hinsdale, IL)

    1997-01-01

    A fault current limiter (10) for an electrical circuit (14). The fault current limiter (10) includes a high temperature superconductor (12) in the electrical circuit (14). The high temperature superconductor (12) is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter (10).

  9. Actuator Fault Detection and Diagnosis for Quadrotors

    NARCIS (Netherlands)

    Lu, P.; Van Kampen, E.-J.; Yu, B.

    2014-01-01

    This paper presents a method for fault detection and diagnosis of actuator loss of effectiveness for a quadrotor helicopter. This paper not only considers the detection of the actuator loss of effectiveness faults, but also addresses the diagnosis of the faults. The detection and estimation of the f

  10. Architecting fault-tolerant software systems

    NARCIS (Netherlands)

    Sözer, Hasan

    2009-01-01

    The increasing size and complexity of software systems makes it hard to prevent or remove all possible faults. Faults that remain in the system can eventually lead to a system failure. Fault tolerance techniques are introduced for enabling systems to recover and continue operation when they are subj

  11. Fault tolerant software modules for SIFT

    Science.gov (United States)

    Hecht, M.; Hecht, H.

    1982-01-01

    The implementation of software fault tolerance is investigated for critical modules of the Software Implemented Fault Tolerance (SIFT) operating system to support the computational and reliability requirements of advanced fly by wire transport aircraft. Fault tolerant designs generated for the error reported and global executive are examined. A description of the alternate routines, implementation requirements, and software validation are included.

  12. The minimum scale of grooving on faults

    NARCIS (Netherlands)

    Candela, T.; Brodsky, E.E.

    2016-01-01

    At the field scale, nearly all fault surfaces contain grooves generated as one side of the fault slips past the other. Grooves are so common that they are one of the key indicators of principal slip surfaces. Here, we show that at sufficiently small scales, grooves do not exist on fault surfaces. A

  13. The minimum scale of grooving on faults

    NARCIS (Netherlands)

    Candela, T.; Brodsky, E.E.

    2016-01-01

    At the field scale, nearly all fault surfaces contain grooves generated as one side of the fault slips past the other. Grooves are so common that they are one of the key indicators of principal slip surfaces. Here, we show that at sufficiently small scales, grooves do not exist on fault surfaces. A

  14. Synthesis of Fault-Tolerant Embedded Systems

    DEFF Research Database (Denmark)

    Eles, Petru; Izosimov, Viacheslav; Pop, Paul

    2008-01-01

    This work addresses the issue of design optimization for fault- tolerant hard real-time systems. In particular, our focus is on the handling of transient faults using both checkpointing with rollback recovery and active replication. Fault tolerant schedules are generated based on a conditional pr...

  15. Fault Tolerant Frequent Pattern Mining

    Energy Technology Data Exchange (ETDEWEB)

    Shohdy, Sameh; Vishnu, Abhinav; Agrawal, Gagan

    2016-12-19

    FP-Growth algorithm is a Frequent Pattern Mining (FPM) algorithm that has been extensively used to study correlations and patterns in large scale datasets. While several researchers have designed distributed memory FP-Growth algorithms, it is pivotal to consider fault tolerant FP-Growth, which can address the increasing fault rates in large scale systems. In this work, we propose a novel parallel, algorithm-level fault-tolerant FP-Growth algorithm. We leverage algorithmic properties and MPI advanced features to guarantee an O(1) space complexity, achieved by using the dataset memory space itself for checkpointing. We also propose a recovery algorithm that can use in-memory and disk-based checkpointing, though in many cases the recovery can be completed without any disk access, and incurring no memory overhead for checkpointing. We evaluate our FT algorithm on a large scale InfiniBand cluster with several large datasets using up to 2K cores. Our evaluation demonstrates excellent efficiency for checkpointing and recovery in comparison to the disk-based approach. We have also observed 20x average speed-up in comparison to Spark, establishing that a well designed algorithm can easily outperform a solution based on a general fault-tolerant programming model.

  16. Fault detection using (PI) observers

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, J.; Shafai, B.

    The fault detection and isolation (FDI) problem in connection with Proportional Integral (PI) Observers is considered in this paper. A compact formulation of the FDI design problem using PI observers is given. An analysis of the FDI design problem is derived with respectt to the time domain...... properties. A method for design of PI observers applied to FDI is given....

  17. Fault Detection for Nonlinear Systems

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.H.

    1998-01-01

    The paper describes a general method for designing fault detection and isolation (FDI) systems for nonlinear processes. For a rich class of nonlinear systems, a nonlinear FDI system can be designed using convex optimization procedures. The proposed method is a natural extension of methods based...

  18. Tsunamis and splay fault dynamics

    Science.gov (United States)

    Wendt, J.; Oglesby, D.D.; Geist, E.L.

    2009-01-01

    The geometry of a fault system can have significant effects on tsunami generation, but most tsunami models to date have not investigated the dynamic processes that determine which path rupture will take in a complex fault system. To gain insight into this problem, we use the 3D finite element method to model the dynamics of a plate boundary/splay fault system. We use the resulting ground deformation as a time-dependent boundary condition for a 2D shallow-water hydrodynamic tsunami calculation. We find that if me stress distribution is homogeneous, rupture remains on the plate boundary thrust. When a barrier is introduced along the strike of the plate boundary thrust, rupture propagates to the splay faults, and produces a significantly larger tsunami man in the homogeneous case. The results have implications for the dynamics of megathrust earthquakes, and also suggest mat dynamic earthquake modeling may be a useful tool in tsunami researcn. Copyright 2009 by the American Geophysical Union.

  19. Fault current limiters using superconductors

    Science.gov (United States)

    Norris, W. T.; Power, A.

    Fault current limiters on power systems are to reduce damage by heating and electromechanical forces, to alleviate duty on switchgear used to clear the fault, and to mitigate disturbance to unfaulted parts of the system. A basic scheme involves a super-resistor which is a superconductor being driven to high resistance when fault current flows either when current is high during a cycle of a.c. or, if the temperature of the superconductive material rises, for the full cycle. Current may be commuted from superconductor to an impedance in parallel, thus reducing the energy dispersed at low temperature and saving refrigeration. In a super-shorted transformer the ambient temperature primary carries the power system current; the superconductive secondary goes to a resistive condition when excessive currents flow in the primary. A super-transformer has the advantage of not needing current leads from high temperature to low temperature; it behaves as a parallel super-resistor and inductor. The supertransductor with a superconductive d.c. bias winding is large and has small effect on the rate of fall of current at current zero; it does little to alleviate duty on switchgear but does reduce heating and electromechanical forces. It is fully active after a fault has been cleared. Other schemes depend on rapid recooling of the superconductor to achieve this.

  20. Architecture of small-scale fault zones in the context of the Leinetalgraben Fault System

    Science.gov (United States)

    Reyer, Dorothea; Philipp, Sonja L.

    2010-05-01

    Understanding fault zone properties in different geological settings is important to better assess the development and propagation of faults. In addition this allows better evaluation and permeability estimates of potential fault-related geothermal reservoirs. The Leinetalgraben fault system provides an outcrop analogue for many fault zones in the subsurface of the North German Basin. The Leinetalgraben is a N-S-trending graben structure, initiated in the Jurassic, in the south of Lower Saxony and as such part of the North German Basin. The fault system was reactivated and inverted during Alpine compression in the Tertiary. This complex geological situation was further affected by halotectonics. Therefore we can find different types of fault zones, that is normal, reverse, strike-slip an oblique-slip faults, surrounding the major Leinetalgraben boundary faults. Here we present first results of structural geological field studies on the geometry and architecture of fault zones in the Leinetalgraben Fault System in outcrop-scale. We measured the orientations and displacements of 17 m-scale fault zones in limestone (Muschelkalk) outcrops, the thicknesses of their fault cores and damage zones, as well as the fracture densities and geometric parameters of the fracture systems therein. We also analysed the effects of rock heterogeneities, particularly stiffness variations between layers (mechanical layering) on the propagation of natural fractures and fault zones. The analysed fault zones predominantly show similar orientations as the major fault zones they surround. Other faults are conjugate or perpendicular to the major fault zones. The direction of predominant joint strike corresponds to the orientation of the fault zones in the majority of cases. The mechanical layering of the limestone and marlstone stratification obviously has great effects on fracture propagation. Already thin layers (mm- to cm-scale) of low stiffness - here marl - seem to suffice to change the

  1. H infinity Integrated Fault Estimation and Fault Tolerant Control of Discrete-time Piecewise Linear Systems

    DEFF Research Database (Denmark)

    Tabatabaeipour, Seyed Mojtaba; Bak, Thomas

    2012-01-01

    In this paper we consider the problem of fault estimation and accommodation for discrete time piecewise linear systems. A robust fault estimator is designed to estimate the fault such that the estimation error converges to zero and H∞ performance of the fault estimation is minimized. Then......, the estimate of fault is used to compensate for the effect of the fault. Hence, using the estimate of fault, a fault tolerant controller using a piecewise linear static output feedback is designed such that it stabilizes the system and provides an upper bound on the H∞ performance of the faulty system....... Sufficient conditions for the existence of robust fault estimator and fault tolerant controller are derived in terms of linear matrix inequalities. Upper bounds on the H∞ performance can be minimized by solving convex optimization problems with linear matrix inequality constraints. The efficiency...

  2. Fault diagnosis and fault-tolerant control based on adaptive control approach

    CERN Document Server

    Shen, Qikun; Shi, Peng

    2017-01-01

    This book provides recent theoretical developments in and practical applications of fault diagnosis and fault tolerant control for complex dynamical systems, including uncertain systems, linear and nonlinear systems. Combining adaptive control technique with other control methodologies, it investigates the problems of fault diagnosis and fault tolerant control for uncertain dynamic systems with or without time delay. As such, the book provides readers a solid understanding of fault diagnosis and fault tolerant control based on adaptive control technology. Given its depth and breadth, it is well suited for undergraduate and graduate courses on linear system theory, nonlinear system theory, fault diagnosis and fault tolerant control techniques. Further, it can be used as a reference source for academic research on fault diagnosis and fault tolerant control, and for postgraduates in the field of control theory and engineering. .

  3. Toward Explaining Scale-dependent Velocity Structure Across an Exposed Brittle Fault Zone

    Science.gov (United States)

    Gettemy, G. L.; Tobin, H. J.; Hole, J. A.; Sayed, A. Y.

    2001-12-01

    The lack of preserved surface exposures of faults generally necessitates the use of remote-sensed data to infer lithostructural architecture of the subsurface of any particular fault, particularly seismic experiments which detail physical properties linked to wave propagation phenomena. The exposure of the San Gregorio Fault at Moss Beach (25 km southwest of San Francisco, CA), however, provides a unique opportunity to examine a preserved active fault zone. We combine two scales of geophysical investigation--high-resolution field velocity tomography, and an extensive laboratory ultrasonic velocity measurement program--to produce a 1D across-fault velocity structure that correlates well with the previously mapped structural domains. The absolute velocities within a given domain are strongly scale dependent, with the laboratory velocities 20-50% greater than the field-scale tomography results. This disparity can potentially be attributed to sampling bias (i.e., the inability to sample and ultrasonically test macroscopically fractured rock near \\textit{in situ} conditions), saturation effects, and frequency dispersion. We investigate the importance of the mesoscopic fracture distribution and depositional heterogeneity on the velocity discrepancies through monte carlo analysis by applying an effective medium theory of multi-scaled fractured rock combined with a propagator matrix algorithm. We parameterize the model by generating a 1D model of the fault zone, incorporating dispersion-adjusted saturated rock velocities and mesoscopic fracture distributions consistent with ultrasonic measurements and field-scale geologic mapping. The results clearly demonstrate that differing elastomechanical parameters must be invoked to explain the velocity discrepancy within the hanging wall (massive mudstone) and foot wall (sandstone with interbedded pebble conglomerate). These results highlight the value of conducting multi-scaled investigations when studying complex fault zone

  4. Monte Carlo simulation of photon migration in a cloud computing environment with MapReduce.

    Science.gov (United States)

    Pratx, Guillem; Xing, Lei

    2011-12-01

    Monte Carlo simulation is considered the most reliable method for modeling photon migration in heterogeneous media. However, its widespread use is hindered by the high computational cost. The purpose of this work is to report on our implementation of a simple MapReduce method for performing fault-tolerant Monte Carlo computations in a massively-parallel cloud computing environment. We ported the MC321 Monte Carlo package to Hadoop, an open-source MapReduce framework. In this implementation, Map tasks compute photon histories in parallel while a Reduce task scores photon absorption. The distributed implementation was evaluated on a commercial compute cloud. The simulation time was found to be linearly dependent on the number of photons and inversely proportional to the number of nodes. For a cluster size of 240 nodes, the simulation of 100 billion photon histories took 22 min, a 1258 × speed-up compared to the single-threaded Monte Carlo program. The overall computational throughput was 85,178 photon histories per node per second, with a latency of 100 s. The distributed simulation produced the same output as the original implementation and was resilient to hardware failure: the correctness of the simulation was unaffected by the shutdown of 50% of the nodes.

  5. Fault-Tolerant Heat Exchanger

    Science.gov (United States)

    Izenson, Michael G.; Crowley, Christopher J.

    2005-01-01

    A compact, lightweight heat exchanger has been designed to be fault-tolerant in the sense that a single-point leak would not cause mixing of heat-transfer fluids. This particular heat exchanger is intended to be part of the temperature-regulation system for habitable modules of the International Space Station and to function with water and ammonia as the heat-transfer fluids. The basic fault-tolerant design is adaptable to other heat-transfer fluids and heat exchangers for applications in which mixing of heat-transfer fluids would pose toxic, explosive, or other hazards: Examples could include fuel/air heat exchangers for thermal management on aircraft, process heat exchangers in the cryogenic industry, and heat exchangers used in chemical processing. The reason this heat exchanger can tolerate a single-point leak is that the heat-transfer fluids are everywhere separated by a vented volume and at least two seals. The combination of fault tolerance, compactness, and light weight is implemented in a unique heat-exchanger core configuration: Each fluid passage is entirely surrounded by a vented region bridged by solid structures through which heat is conducted between the fluids. Precise, proprietary fabrication techniques make it possible to manufacture the vented regions and heat-conducting structures with very small dimensions to obtain a very large coefficient of heat transfer between the two fluids. A large heat-transfer coefficient favors compact design by making it possible to use a relatively small core for a given heat-transfer rate. Calculations and experiments have shown that in most respects, the fault-tolerant heat exchanger can be expected to equal or exceed the performance of the non-fault-tolerant heat exchanger that it is intended to supplant (see table). The only significant disadvantages are a slight weight penalty and a small decrease in the mass-specific heat transfer.

  6. Fault Diagnosis in HVAC Chillers

    Science.gov (United States)

    Choi, Kihoon; Namuru, Setu M.; Azam, Mohammad S.; Luo, Jianhui; Pattipati, Krishna R.; Patterson-Hine, Ann

    2005-01-01

    Modern buildings are being equipped with increasingly sophisticated power and control systems with substantial capabilities for monitoring and controlling the amenities. Operational problems associated with heating, ventilation, and air-conditioning (HVAC) systems plague many commercial buildings, often the result of degraded equipment, failed sensors, improper installation, poor maintenance, and improperly implemented controls. Most existing HVAC fault-diagnostic schemes are based on analytical models and knowledge bases. These schemes are adequate for generic systems. However, real-world systems significantly differ from the generic ones and necessitate modifications of the models and/or customization of the standard knowledge bases, which can be labor intensive. Data-driven techniques for fault detection and isolation (FDI) have a close relationship with pattern recognition, wherein one seeks to categorize the input-output data into normal or faulty classes. Owing to the simplicity and adaptability, customization of a data-driven FDI approach does not require in-depth knowledge of the HVAC system. It enables the building system operators to improve energy efficiency and maintain the desired comfort level at a reduced cost. In this article, we consider a data-driven approach for FDI of chillers in HVAC systems. To diagnose the faults of interest in the chiller, we employ multiway dynamic principal component analysis (MPCA), multiway partial least squares (MPLS), and support vector machines (SVMs). The simulation of a chiller under various fault conditions is conducted using a standard chiller simulator from the American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE). We validated our FDI scheme using experimental data obtained from different types of chiller faults.

  7. Fault Diagnosis in HVAC Chillers

    Science.gov (United States)

    Choi, Kihoon; Namuru, Setu M.; Azam, Mohammad S.; Luo, Jianhui; Pattipati, Krishna R.; Patterson-Hine, Ann

    2005-01-01

    Modern buildings are being equipped with increasingly sophisticated power and control systems with substantial capabilities for monitoring and controlling the amenities. Operational problems associated with heating, ventilation, and air-conditioning (HVAC) systems plague many commercial buildings, often the result of degraded equipment, failed sensors, improper installation, poor maintenance, and improperly implemented controls. Most existing HVAC fault-diagnostic schemes are based on analytical models and knowledge bases. These schemes are adequate for generic systems. However, real-world systems significantly differ from the generic ones and necessitate modifications of the models and/or customization of the standard knowledge bases, which can be labor intensive. Data-driven techniques for fault detection and isolation (FDI) have a close relationship with pattern recognition, wherein one seeks to categorize the input-output data into normal or faulty classes. Owing to the simplicity and adaptability, customization of a data-driven FDI approach does not require in-depth knowledge of the HVAC system. It enables the building system operators to improve energy efficiency and maintain the desired comfort level at a reduced cost. In this article, we consider a data-driven approach for FDI of chillers in HVAC systems. To diagnose the faults of interest in the chiller, we employ multiway dynamic principal component analysis (MPCA), multiway partial least squares (MPLS), and support vector machines (SVMs). The simulation of a chiller under various fault conditions is conducted using a standard chiller simulator from the American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE). We validated our FDI scheme using experimental data obtained from different types of chiller faults.

  8. Robust Fault Diagnosis Design for Linear Multiagent Systems with Incipient Faults

    Directory of Open Access Journals (Sweden)

    Jingping Xia

    2015-01-01

    Full Text Available The design of a robust fault estimation observer is studied for linear multiagent systems subject to incipient faults. By considering the fact that incipient faults are in low-frequency domain, the fault estimation of such faults is proposed for discrete-time multiagent systems based on finite-frequency technique. Moreover, using the decomposition design, an equivalent conclusion is given. Simulation results of a numerical example are presented to demonstrate the effectiveness of the proposed techniques.

  9. Langevin Monte Carlo filtering for target tracking

    NARCIS (Netherlands)

    Iglesias Garcia, Fernando; Bocquel, Melanie; Driessen, Hans

    2015-01-01

    This paper introduces the Langevin Monte Carlo Filter (LMCF), a particle filter with a Markov chain Monte Carlo algorithm which draws proposals by simulating Hamiltonian dynamics. This approach is well suited to non-linear filtering problems in high dimensional state spaces where the bootstrap filte

  10. An introduction to Monte Carlo methods

    NARCIS (Netherlands)

    Walter, J. -C.; Barkema, G. T.

    2015-01-01

    Monte Carlo simulations are methods for simulating statistical systems. The aim is to generate a representative ensemble of configurations to access thermodynamical quantities without the need to solve the system analytically or to perform an exact enumeration. The main principles of Monte Carlo sim

  11. An introduction to Monte Carlo methods

    NARCIS (Netherlands)

    Walter, J. -C.; Barkema, G. T.

    2015-01-01

    Monte Carlo simulations are methods for simulating statistical systems. The aim is to generate a representative ensemble of configurations to access thermodynamical quantities without the need to solve the system analytically or to perform an exact enumeration. The main principles of Monte Carlo sim

  12. Challenges of Monte Carlo Transport

    Energy Technology Data Exchange (ETDEWEB)

    Long, Alex Roberts [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-10

    These are slides from a presentation for Parallel Summer School at Los Alamos National Laboratory. Solving discretized partial differential equations (PDEs) of interest can require a large number of computations. We can identify concurrency to allow parallel solution of discrete PDEs. Simulated particles histories can be used to solve the Boltzmann transport equation. Particle histories are independent in neutral particle transport, making them amenable to parallel computation. Physical parameters and method type determine the data dependencies of particle histories. Data requirements shape parallel algorithms for Monte Carlo. Then, Parallel Computational Physics and Parallel Monte Carlo are discussed and, finally, the results are given. The mesh passing method greatly simplifies the IMC implementation and allows simple load-balancing. Using MPI windows and passive, one-sided RMA further simplifies the implementation by removing target synchronization. The author is very interested in implementations of PGAS that may allow further optimization for one-sided, read-only memory access (e.g. Open SHMEM). The MPICH_RMA_OVER_DMAPP option and library is required to make one-sided messaging scale on Trinitite - Moonlight scales poorly. Interconnect specific libraries or functions are likely necessary to ensure performance. BRANSON has been used to directly compare the current standard method to a proposed method on idealized problems. The mesh passing algorithm performs well on problems that are designed to show the scalability of the particle passing method. BRANSON can now run load-imbalanced, dynamic problems. Potential avenues of improvement in the mesh passing algorithm will be implemented and explored. A suite of test problems that stress DD methods will elucidate a possible path forward for production codes.

  13. Numerical modelling of the mechanical and fluid flow properties of fault zones - Implications for fault seal analysis

    NARCIS (Netherlands)

    Heege, J.H. ter; Wassing, B.B.T.; Giger, S.B.; Clennell, M.B.

    2009-01-01

    Existing fault seal algorithms are based on fault zone composition and fault slip (e.g., shale gouge ratio), or on fault orientations within the contemporary stress field (e.g., slip tendency). In this study, we aim to develop improved fault seal algorithms that account for differences in fault zone

  14. Mesoscopic Structural Observations of Cores from the Chelungpu Fault System, Taiwan Chelungpu-Fault Drilling Project Hole-A, Taiwan

    Directory of Open Access Journals (Sweden)

    Hiroki Sone

    2007-01-01

    Full Text Available Structural characteristics of fault rocks distributed within major fault zones provide basic information in understanding the physical aspects of faulting. Mesoscopic structural observations of the drilledcores from Taiwan Chelungpu-fault Drilling Project Hole-A are reported in this article to describe and reveal the distribution of fault rocks within the Chelungpu Fault System.

  15. The MC21 Monte Carlo Transport Code

    Energy Technology Data Exchange (ETDEWEB)

    Sutton TM, Donovan TJ, Trumbull TH, Dobreff PS, Caro E, Griesheimer DP, Tyburski LJ, Carpenter DC, Joo H

    2007-01-09

    MC21 is a new Monte Carlo neutron and photon transport code currently under joint development at the Knolls Atomic Power Laboratory and the Bettis Atomic Power Laboratory. MC21 is the Monte Carlo transport kernel of the broader Common Monte Carlo Design Tool (CMCDT), which is also currently under development. The vision for CMCDT is to provide an automated, computer-aided modeling and post-processing environment integrated with a Monte Carlo solver that is optimized for reactor analysis. CMCDT represents a strategy to push the Monte Carlo method beyond its traditional role as a benchmarking tool or ''tool of last resort'' and into a dominant design role. This paper describes various aspects of the code, including the neutron physics and nuclear data treatments, the geometry representation, and the tally and depletion capabilities.

  16. Diagnosis and Fault-tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Kinnaert, Michel; Lunze, Jan;

    The book presents effective model-based analysis and design methods for fault diagnosis and fault-tolerant control. Architectural and structural models are used to analyse the propagation of the fault through the process, to test the fault detectability and to find the redundancies in the process...... the applicability of the presented methods. The theoretical results are illustrated by two running examples which are used throughout the book. The book addresses engineering students, engineers in industry and researchers who wish to get a survey over the variety of approaches to process diagnosis and fault...

  17. Active fault diagnosis by controller modification

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, Hans Henrik

    2010-01-01

    Two active fault diagnosis methods for additive or parametric faults are proposed. Both methods are based on controller reconfiguration rather than on requiring an exogenous excitation signal, as it is otherwise common in active fault diagnosis. For the first method, it is assumed that the system...... in a way that guarantees the continuity of transition and global stability using a recent result on observer parameterization. An illustrative example inspired by a field study of a drag racing vehicle is given. For the second method, an active fault diagnosis method for parametric faults is proposed...

  18. Bridging faults in BiCMOS circuits

    Science.gov (United States)

    Menon, Sankaran M.; Malaiya, Yashwant K.; Jayasumana, Anura P.

    1993-01-01

    Combining the advantages of CMOS and bipolar, BiCMOS is emerging as a major technology for many high performance digital and mixed signal applications. Recent investigations revealed that bridging faults can be a major failure mode in IC's. Effects of bridging faults in BiCMOS circuits are presented. Bridging faults between logical units without feedback and logical units with feedback are considered. Several bridging faults can be detected by monitoring the power supply current (I(sub DDQ) monitoring). Effects of bridging faults and bridging resistance on output logic levels were examined along with their effects on noise immunity.

  19. Hydrogen release: new indicator of fault activity.

    Science.gov (United States)

    Wakita, H; Nakamura, Y; Kita, I; Fujii, N; Notsu, K

    1980-10-10

    The hydrogen concentration in soil gas has been measured in the area around the Yamasaki Fault, one of the active faults in southwestern Japan. Degassing of a significant amount of hydrogen (up to more than 3 percent by volume) has been observed for sites along the fault zone. The hydrogen concentration in soil gas at sites away from the fault zone was about 0.5 part per million, almost the same as that found in the atmosphere. The spatial distribution of sites with high hydrogen concentrations is quite systematic. A hypothesis on the production of hydrogen by fault movements is postulated.

  20. Improved DFIG Capability during Asymmetrical Grid Faults

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede

    2015-01-01

    , the capability of a 2 MW DFIG to ride through asymmetrical grid faults can be estimated at the existing design of the power electronics converter. Finally, a control scheme aimed to improve the DFIG capability is proposed and the simulation results validate its feasibility.......In the wind power application, different asymmetrical types of the grid fault can be categorized after the Y/d transformer, and the positive and negative components of a single-phase fault, phase-to-phase fault, and two-phase fault can be summarized. Due to the newly introduced negative and even...

  1. Analysis of tectonic structures and excavation induced fractures in the Opalinus Clay, Mont Terri underground rock laboratory (Switzerland)

    Energy Technology Data Exchange (ETDEWEB)

    Nussbaum, Ch.; Bossart, P. [Federal Office of Topography swisstopo, Wabern (Switzerland); Amann, F. [Swiss Federal Institute of Technology Zuerich, Zuerich (Switzerland); Aubourg, Ch. [Laboratoire des fluides complexes et leurs reservoirs, Centre National de la Recherche Scientitfique CNRS, Universite de Pau, Pau (France)

    2011-09-15

    Excavated in the Opalinus Clay formation, the Mont Terri underground rock laboratory in the Jura Mountains of NW Switzerland is an important international test site for researching argillaceous formations, particularly in the context of deep geological disposal of radioactive waste. The rock laboratory is intersected by naturally formed tectonic structures, as well as artificial fractures primarily formed as a consequence of tunnel excavation and the associated stress redistribution. The description and characterisation of tectonic and artificial structures is, in many cases, of key importance for interpreting the results of the various in situ experiments conducted in the rock laboratory. Systematic small-scale mapping of the tunnel walls and floor, and adjacent niches, provides basic information about the geometry and the kinematics of the geological fractures intersecting the underground laboratory. A compilation of all tectonic structures identified is presented in this paper. The underground laboratory is located in the backlimb of the Mont Terri anticline, a NNW-vergent imbricate fault-bend fold, which is characterised by a pronounced along-strike asymmetry resulting from variously oriented inherited faults. The total shortening accommodated by this structure was estimated by mass (area) balancing to be approximately 2.1 km. The Mont Terri area is significantly affected by N- to NNE-striking normal faults of the Eo-Oligocene Rhine-Bresse transfer zone and by ENE-striking faults of Late Variscan age. Depending on their orientation with respect to the transport direction towards the NNW, these faults served as oblique and frontal ramps during the subsequent Jura thrusting in the Late Miocene. The various fault systems identified in the underground rock laboratory clearly correlate with the regional-scale structures. In addition to classical structural analysis, the anisotropy of magnetic susceptibility was measured to determine the magnetic fabric and strain

  2. Tool for Viewing Faults Under Terrain

    Science.gov (United States)

    Siegel, Herbert, L.; Li, P. Peggy

    2005-01-01

    Multi Surface Light Table (MSLT) is an interactive software tool that was developed in support of the QuakeSim project, which has created an earthquake- fault database and a set of earthquake- simulation software tools. MSLT visualizes the three-dimensional geometries of faults embedded below the terrain and animates time-varying simulations of stress and slip. The fault segments, represented as rectangular surfaces at dip angles, are organized into collections, that is, faults. An interface built into MSLT queries and retrieves fault definitions from the QuakeSim fault database. MSLT also reads time-varying output from one of the QuakeSim simulation tools, called "Virtual California." Stress intensity is represented by variations in color. Slips are represented by directional indicators on the fault segments. The magnitudes of the slips are represented by the duration of the directional indicators in time. The interactive controls in MSLT provide a virtual track-ball, pan and zoom, translucency adjustment, simulation playback, and simulation movie capture. In addition, geographical information on the fault segments and faults is displayed on text windows. Because of the extensive viewing controls, faults can be seen in relation to one another, and to the terrain. These relations can be realized in simulations. Correlated slips in parallel faults are visible in the playback of Virtual California simulations.

  3. ESR dating of the fault rocks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hee Kwon [Kangwon National Univ., Chuncheon (Korea, Republic of)

    2004-01-15

    Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then grow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs, grain size shows a plateau for grains below critical size : these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected near the Ulzin nuclear reactor. ESR signals of quartz grains separated from fault rocks collected from the E-W trend fault are saturated. This indicates that the last movement of these faults had occurred before the quaternary period. ESR dates from the NW trend faults range from 300ka to 700ka. On the other hand, ESR date of the NS trend fault is about 50ka. Results of this research suggest that long-term cyclic fault activity near the Ulzin nuclear reactor continued into the pleistocene.

  4. A Quaternary fault database for central Asia

    Science.gov (United States)

    Mohadjer, Solmaz; Ehlers, Todd Alan; Bendick, Rebecca; Stübner, Konstanze; Strube, Timo

    2016-02-01

    Earthquakes represent the highest risk in terms of potential loss of lives and economic damage for central Asian countries. Knowledge of fault location and behavior is essential in calculating and mapping seismic hazard. Previous efforts in compiling fault information for central Asia have generated a large amount of data that are published in limited-access journals with no digital maps publicly available, or are limited in their description of important fault parameters such as slip rates. This study builds on previous work by improving access to fault information through a web-based interactive map and an online database with search capabilities that allow users to organize data by different fields. The data presented in this compilation include fault location, its geographic, seismic, and structural characteristics, short descriptions, narrative comments, and references to peer-reviewed publications. The interactive map displays 1196 fault traces and 34 000 earthquake locations on a shaded-relief map. The online database contains attributes for 123 faults mentioned in the literature, with Quaternary and geodetic slip rates reported for 38 and 26 faults respectively, and earthquake history reported for 39 faults. All data are accessible for viewing and download via http://www.geo.uni-tuebingen.de/faults/. This work has implications for seismic hazard studies in central Asia as it summarizes important fault parameters, and can reduce earthquake risk by enhancing public access to information. It also allows scientists and hazard assessment teams to identify structures and regions where data gaps exist and future investigations are needed.

  5. Accelerated Techniques in Stem Fault Simulation

    Institute of Scientific and Technical Information of China (English)

    石茵; 魏道政

    1996-01-01

    In order to cope with the most expensive stem fault simulation in fault simulation field.several accelerated techniques are presented in this paper.These techniques include static analysis on circuit structure in preprocessing stage and dynamic calculations in fault simulation stage.With these techniques,the area for stem for stem fault simulation and number of the stems requiring explicit fault simulation are greatly reduced,so that the entire fault simulation time is substantially decreased.Experimental results given in this paper show that the fault simulation algorithm using these techniques is of very high efficiency for both small and large numbers of test patterns.Especially with the increase of circuit gates,its effectiveness improves obviously.

  6. Arc burst pattern analysis fault detection system

    Science.gov (United States)

    Russell, B. Don (Inventor); Aucoin, B. Michael (Inventor); Benner, Carl L. (Inventor)

    1997-01-01

    A method and apparatus are provided for detecting an arcing fault on a power line carrying a load current. Parameters indicative of power flow and possible fault events on the line, such as voltage and load current, are monitored and analyzed for an arc burst pattern exhibited by arcing faults in a power system. These arcing faults are detected by identifying bursts of each half-cycle of the fundamental current. Bursts occurring at or near a voltage peak indicate arcing on that phase. Once a faulted phase line is identified, a comparison of the current and voltage reveals whether the fault is located in a downstream direction of power flow toward customers, or upstream toward a generation station. If the fault is located downstream, the line is de-energized, and if located upstream, the line may remain energized to prevent unnecessary power outages.

  7. Structural control of the Limagne Rift Fault on the Chaîne des Puys

    Science.gov (United States)

    Van Wyk de Vries, B.; Tiu, G.; Mossoux, S.; Kervyn, M.; Lagmay, A. A.

    2012-12-01

    The close proximity of the Limagne Fault to the Chaîne des Puys (Massif Central, France) has been noted for a long time. In fact, if the Limagne fault had not raised the Chaîne relative to the Limagne Rift, to create a spectacular skyline of volcanoes, there would probably not have been so much interest in them. Early geologists such as Elie de Beaumont, Davy, Lyell, Murchison, and Von Humbolt, were as much concerned with explaining the escarpment by catastrophism or uniformitarianism, as they were with battling over neptunism and plutonism, or craters of elevation. The questions still stands as to what relationship the monogenetic volcanoes have to the fault, and perhaps: are the volcanoes monogenetic because of the fault? - seeing as just to the south of the rift, stand the Mont Dore-Sancy and Cantal stratovolcanoes. Considering the spatial-temporal relationship, it becomes clear that there are volcanoes on the fault, in the rift, and behind the footwall, but with different ages and configurations. Early volcanoes are cut by the faulting, showing a potential linkage, later volcanoes, as a whole, follow generally the main structural trend NS of the rift, but in detail group around a more NE-SW trend, that can be related to Hercynian structures, and to a major transfer fault linking the Limagne Rift to the Rhine Graben. These trends host some of the youngest volcanoes, and the fault appears to have been more recently active in this area, and the area of some damaging historic earthquakes. Considering the proximity of the fault as an influence in the monogenetic nature of the volcanism, more needs to be known about the state of faulting in the Tertiary in the Massif Central. However, the area of the Chaîne de Puys is highly heterogeneous, with complex associations of Hercynian and Tertiary structures, and thus the crustal structure may be compatible with multiple pathways, and thus a monogenetic tendency. In conclusion, there is a probably spatial and temporal

  8. Contemporary fault mechanics in southern Alaska

    Science.gov (United States)

    Kalbas, James L.; Freed, Andrew M.; Ridgway, Kenneth D.

    Thin-shell finite-element models, constrained by a limited set of geologic slip rates, provide a tool for evaluating the organization of contemporary faulting in southeastern Alaska. The primary structural features considered in our analysis are the Denali, Duke River, Totschunda, Fairweather, Queen Charlotte, and Transition faults. The combination of fault configurations and rheological properties that best explains observed geologic slip rates predicts that the Fairweather and Totschunda faults are joined by an inferred southeast-trending strike-slip fault that crosses the St. Elias Mountains. From a regional perspective, this structure, which our models suggest slips at a rate of ˜8 mm/a, transfers shear from the Queen Charlotte fault in southeastern Alaska and British Columbia northward to the Denali fault in central Alaska. This result supports previous hypotheses that the Fairweather-Totschunda connecting fault constitutes a newly established northward extension of the Queen Charlotte-Fairweather transform system and helps accommodate right-lateral motion (˜49 mm/a) of the Pacific plate and Yakutat microplate relative to stable North America. Model results also imply that the Transition fault separating the Yakutat microplate from the Pacific plate is favorably oriented to accommodate significant thrusting (23 mm/a). Rapid dip-slip displacement on the Transition fault does not, however, draw shear off of the Queen Charlotte-Fairweather transform fault system. Our new modeling results suggest that the Totschunda fault, the proposed Fairweather-Totschunda connecting fault, and the Fairweather fault may represent the youngest stage of southwestward migration of the active strike-slip deformation front in the long-term evolution of this convergent margin.

  9. 3D simulation of near-fault strong ground motion:comparison between surface rupture fault and buried fault

    Institute of Scientific and Technical Information of China (English)

    Liu Qifang; Yuan Yifan; Jin Xing

    2007-01-01

    In this paper,near-fault strong ground motions caused by a surface rupture fault(SRF)and a buried fault(BF) are numerically simulated and compared by using a time-space-decoupled,explicit finite element method combined with a multi-transmitting formula(MTF) of an artificial boundary.Prior to the comparison,verification of the explicit element method and the MTF is conducted.The comparison results show that the final dislocation of the SRF is larger than the BF for the same stress drop on the fault plane.The maximum final dislocation occurs on the fault upper line for the SRF;however,for the BF,the maximum final dislocation is located on the fault central part.Meanwhile,the PGA,PGV and PGD of long period ground motions(≤1 Hz)generated by the SRF are much higher than those of the BF in the near-fault region.The peak value of the velocity pulse generated by the SRF is also higher than the BF.Furthermore,it is found that in a very narrow region along the fault trace,ground motions caused by the SRF are much higher than by the BF.These results may explain why SRFs almost always cause heavy damage in near-fault regions compared to buried faults.

  10. Identifying fault segments from 3D fault drag analysis (Vienna Basin, Austria)

    Science.gov (United States)

    Spahić, Darko; Grasemann, Bernhard; Exner, Ulrike

    2013-10-01

    The segmented growth of the Markgrafneusiedl normal fault in the late Miocene clastic sediments of the central Vienna Basin (Austria) was investigated by construction of a detailed three-dimensional (3D) structural model. Using high resolution 3D seismic data, the fault surface and marker horizons in the hanging wall and the footwall of the Markgrafneusiedl Fault were mapped and orientation, displacement and morphology of the fault surface were quantified. Individual, fault segments were identified by direct mapping of the deflection of the marker horizons close to the fault surface. Correlating the size of the identified segments with the magnitude of fault drag and displacement distribution showed that fault evolution progressed in several stages. The proposed method allows the detection of segments that are not recorded by the magnitude of displacement or fault morphology. Most importantly, detailed mapping of marker deflections in the hanging wall could help to constrain equivalent structures in the footwall, which may represent potential hydrocarbon traps.

  11. Spike Inference from Calcium Imaging using Sequential Monte Carlo Methods

    OpenAIRE

    NeuroData; Paninski, L

    2015-01-01

    Vogelstein JT, Paninski L. Spike Inference from Calcium Imaging using Sequential Monte Carlo Methods. Statistical and Applied Mathematical Sciences Institute (SAMSI) Program on Sequential Monte Carlo Methods, 2008

  12. Fault Injection Techniques and Tools

    Science.gov (United States)

    Hsueh, Mei-Chen; Tsai, Timothy K.; Iyer, Ravishankar K.

    1997-01-01

    Dependability evaluation involves the study of failures and errors. The destructive nature of a crash and long error latency make it difficult to identify the causes of failures in the operational environment. It is particularly hard to recreate a failure scenario for a large, complex system. To identify and understand potential failures, we use an experiment-based approach for studying the dependability of a system. Such an approach is applied not only during the conception and design phases, but also during the prototype and operational phases. To take an experiment-based approach, we must first understand a system's architecture, structure, and behavior. Specifically, we need to know its tolerance for faults and failures, including its built-in detection and recovery mechanisms, and we need specific instruments and tools to inject faults, create failures or errors, and monitor their effects.

  13. Emergency Preparedness and Management at the University of L’aquila (Central Italy) and the Role of Students’ Associations in the April 6th 2009 Earthquake

    Science.gov (United States)

    Magni, Michele; Fraboni, Rita; Marincioni, Fausto

    2017-01-01

    Introduction: On April 6th 2009 an earthquake of Mw=6.3 hit the historical downtown of L’Aquila and its hinterland causing more than 300 fatalities and severe damage to private and public buildings. At the time, the University of L’Aquila represented a major source of employment and income for the city. The earthquake impacted both the facilities and the administrative, financial and patrimonial activities of the university, bringing into the open the tendency – widespread in Italy – to rely on adaptive tactics rather than on strategic pre-disaster plans. This paper investigates the university’s emergency preparedness and response capability and  the strategies adopted to restore the education activities as well as avoid students migration to other universities. In addition, emphasis is placed on the role played by Student Associations in pre and post-disaster phases, and how students perceived the activities performed by these associations. Methods: To achieve this goal, it was undertaken: i) qualitative evaluation to assess the impact of earthquake on services and facilities of the university, the emergency preparedness and the measures adopted to face the emergency, ii) survey on the role played by Student Associations, both in emergency preparedness and response, according to students’ perception; iii) quantitative analysis to measure changes in the enrollment trend after the earthquake, and how university policies could curb students’ migration. Results: The policies adopted by the University allowed to diminish students’ migration; however, the measures taken by the university were based on an ad hoc plan as no emergency and continuity plans were prepared in advance. Similarly Student Associations got involved more in restoration activities than in emergency preparedness and risk awareness promotion. Discussion: Greater awareness and involvement are essential at each level (administrators, faculties, students) to plan in advance for an

  14. Developing Engineered Fuel (Briquettes) Using Fly Ash from the Aquila Coal-Fired Power Plant in Canon City and Locally Available Biomass Waste

    Energy Technology Data Exchange (ETDEWEB)

    H. Carrasco; H. Sarper

    2006-06-30

    The objective of this research is to explore the feasibility of producing engineered fuels from a combination of renewable and non renewable energy sources. The components are flyash (containing coal fines) and locally available biomass waste. The constraints were such that no other binder additives were to be added. Listed below are the main accomplishments of the project: (1) Determination of the carbon content of the flyash sample from the Aquila plant. It was found to be around 43%. (2) Experiments were carried out using a model which simulates the press process of a wood pellet machine, i.e. a bench press machine with a close chamber, to find out the ideal ratio of wood and fly ash to be mixed to get the desired briquette. The ideal ratio was found to have 60% wood and 40% flyash. (3) The moisture content required to produce the briquettes was found to be anything below 5.8%. (4) The most suitable pressure required to extract the lignin form the wood and cause the binding of the mixture was determined to be 3000psi. At this pressure, the briquettes withstood an average of 150psi on its lateral side. (5) An energy content analysis was performed and the BTU content was determined to be approximately 8912 BTU/lb. (6) The environmental analysis was carried out and no abnormalities were noted. (7) Industrial visits were made to pellet manufacturing plants to investigate the most suitable manufacturing process for the briquettes. (8) A simulation model of extrusion process was developed to explore the possibility of using a cattle feed plant operating on extrusion process to produce briquettes. (9) Attempt to produce 2 tons of briquettes was not successful. The research team conducted a trial production run at a Feed Mill in La Junta, CO to produce two (2) tons of briquettes using the extrusion process in place. The goal was to, immediately after producing the briquettes; send them through Aquila's current system to test the ability of the briquettes to flow

  15. Stress and Burnout in Health-Care Workers after the 2009 L’Aquila Earthquake: A Cross-Sectional Observational Study

    Directory of Open Access Journals (Sweden)

    Antonella Mattei

    2017-06-01

    Full Text Available Burnout is a work-related mental health impairment, which is now recognized as a real problem in the context of the helping professions due to its adverse health outcomes on efficiency. To our knowledge, the literature on the postdisaster scenario in Italy is limited by a focus on mental health professionals rather than other health-care workers. Our cross-sectional study aims to evaluate the prevalence of burnout and psychopathological distress in different categories of health-care workers, i.e., physicians, nurses, and health-care assistants, working in different departments of L’Aquila St. Salvatore General Hospital 6 years after the 2009 earthquake in order to prevent and reduce work-related burnout. With a two-stage cluster sampling, a total of 8 departments out of a total of 28 departments were selected and the total sample included 300 health-care workers. All the participants completed the following self-reporting questionnaires: a sociodemographic data form, a Maslach Burnout Inventory and a General Health Questionnaire 12 Items (GHQ-12. Statistically significant differences emerged between the total scores of the GHQ-12: post hoc analysis showed that the total average scores of the GHQ-12 were significantly higher in doctors than in health-care assistants. A high prevalence of burnout among doctors (25.97% emerged. Using multivariate analysis, we identified a hostile relationship with colleagues, direct exposure to the L’Aquila earthquake and moderate to high levels of distress as being burnout predictors. Investigating the prevalence of burnout and distress in health-care staff in a postdisaster setting and identifying predictors of burnout development such as stress levels, time-management skills and work-life balance will contribute to the development of preventative strategies and better organization at work with a view to improving public health efficacy and reducing public health costs, given that these workers live in the

  16. Stress and Burnout in Health-Care Workers after the 2009 L'Aquila Earthquake: A Cross-Sectional Observational Study.

    Science.gov (United States)

    Mattei, Antonella; Fiasca, Fabiana; Mazzei, Mariachiara; Necozione, Stefano; Bianchini, Valeria

    2017-01-01

    Burnout is a work-related mental health impairment, which is now recognized as a real problem in the context of the helping professions due to its adverse health outcomes on efficiency. To our knowledge, the literature on the postdisaster scenario in Italy is limited by a focus on mental health professionals rather than other health-care workers. Our cross-sectional study aims to evaluate the prevalence of burnout and psychopathological distress in different categories of health-care workers, i.e., physicians, nurses, and health-care assistants, working in different departments of L'Aquila St. Salvatore General Hospital 6 years after the 2009 earthquake in order to prevent and reduce work-related burnout. With a two-stage cluster sampling, a total of 8 departments out of a total of 28 departments were selected and the total sample included 300 health-care workers. All the participants completed the following self-reporting questionnaires: a sociodemographic data form, a Maslach Burnout Inventory and a General Health Questionnaire 12 Items (GHQ-12). Statistically significant differences emerged between the total scores of the GHQ-12: post hoc analysis showed that the total average scores of the GHQ-12 were significantly higher in doctors than in health-care assistants. A high prevalence of burnout among doctors (25.97%) emerged. Using multivariate analysis, we identified a hostile relationship with colleagues, direct exposure to the L'Aquila earthquake and moderate to high levels of distress as being burnout predictors. Investigating the prevalence of burnout and distress in health-care staff in a postdisaster setting and identifying predictors of burnout development such as stress levels, time-management skills and work-life balance will contribute to the development of preventative strategies and better organization at work with a view to improving public health efficacy and reducing public health costs, given that these workers live in the disaster

  17. NBTI-Aware Transient Fault Rate Analysis Method for Logic Circuit Based on Probability Voltage Transfer Characteristics

    Directory of Open Access Journals (Sweden)

    Zhiming Yang

    2016-01-01

    Full Text Available The reliability of Very Large Scale Integration (VLSI circuits has become increasingly susceptible to transient faults induced by environmental noise with the scaling of technology. Some commonly used fault tolerance strategies require statistical methods to accurately estimate the fault rate in different parts of the logic circuit, and Monte Carlo (MC simulation is often applied to complete this task. However, the MC method suffers from impractical computation costs due to the size of the circuits. Furthermore, circuit aging effects, such as negative bias temperature instability (NBTI, will change the characteristics of the circuit during its lifetime, leading to a change in the circuit’s noise margin. This change will increase the complexity of transient fault rate estimation tasks. In this paper, an NBTI-aware statistical analysis method based on probability voltage transfer characteristics is proposed for combinational logic circuit. This method can acquire accurate fault rates using a discrete probability density function approximation process, thus resolving the computation cost problem of the MC method. The proposed method can also consider aging effects and analyze statistical changes in the fault rates. Experimental results demonstrate that, compared to the MC simulation, our method can achieve computation times that are two orders of magnitude shorter while maintaining an error rate less than 9%.

  18. Inverter Ground Fault Overvoltage Testing

    Energy Technology Data Exchange (ETDEWEB)

    Hoke, Andy [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nelson, Austin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Chakraborty, Sudipta [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Chebahtah, Justin [SolarCity Corporation, San Mateo, CA (United States); Wang, Trudie [SolarCity Corporation, San Mateo, CA (United States); McCarty, Michael [SolarCity Corporation, San Mateo, CA (United States)

    2015-08-12

    This report describes testing conducted at NREL to determine the duration and magnitude of transient overvoltages created by several commercial PV inverters during ground fault conditions. For this work, a test plan developed by the Forum on Inverter Grid Integration Issues (FIGII) has been implemented in a custom test setup at NREL. Load rejection overvoltage test results were reported previously in a separate technical report.

  19. DC superconducting fault current limiter

    Science.gov (United States)

    Tixador, P.; Villard, C.; Cointe, Y.

    2006-03-01

    There is a lack of satisfying solutions for fault currents using conventional technologies, especially in DC networks, where a superconducting fault current limiter could play a very important part. DC networks bring a lot of advantages when compared to traditional AC ones, in particular within the context of the liberalization of the electric market. Under normal operation in a DC network, the losses in the superconducting element are nearly zero and only a small, i.e. a low cost, refrigeration system is then required. The absence of zero crossing of a DC fault current favourably accelerates the normal zone propagation. The very high current slope at the time of the short circuit in a DC grid is another favourable parameter. The material used for the experiments is YBCO deposited on Al2O3 as well as YBCO coated conductors. The DC limitation experiments are compared to AC ones at different frequencies (50-2000 Hz). Careful attention is paid to the quench homogenization, which is one of the key issues for an SC FCL. The University of Geneva has proposed constrictions. We have investigated an operating temperature higher than 77 K. As for YBCO bulk, an operation closer to the critical temperature brings a highly improved homogeneity in the electric field development. The material can then absorb large energies without degradation. We present tests at various temperatures. These promising results are to be confirmed over long lengths.

  20. Watching Faults Grow in Sand

    Science.gov (United States)

    Cooke, M. L.

    2015-12-01

    Accretionary sandbox experiments provide a rich environment for investigating the processes of fault development. These experiments engage students because 1) they enable direct observation of fault growth, which is impossible in the crust (type 1 physical model), 2) they are not only representational but can also be manipulated (type 2 physical model), 3) they can be used to test hypotheses (type 3 physical model) and 4) they resemble experiments performed by structural geology researchers around the world. The structural geology courses at UMass Amherst utilize a series of accretionary sandboxes experiments where students first watch a video of an experiment and then perform a group experiment. The experiments motivate discussions of what conditions they would change and what outcomes they would expect from these changes; hypothesis development. These discussions inevitably lead to calculations of the scaling relationships between model and crustal fault growth and provide insight into the crustal processes represented within the dry sand. Sketching of the experiments has been shown to be a very effective assessment method as the students reveal which features they are analyzing. Another approach used at UMass is to set up a forensic experiment. The experiment is set up with spatially varying basal friction before the meeting and students must figure out what the basal conditions are through the experiment. This experiment leads to discussions of equilibrium and force balance within the accretionary wedge. Displacement fields can be captured throughout the experiment using inexpensive digital image correlation techniques to foster quantitative analysis of the experiments.

  1. Influence of fault trend, fault bends, and fault convergence on shallow structure, geomorphology, and hazards, Hosgri strike-slip fault, offshore central California

    Science.gov (United States)

    Johnson, S. Y.; Watt, J. T.; Hartwell, S. R.

    2012-12-01

    We mapped a ~94-km-long portion of the right-lateral Hosgri Fault Zone from Point Sal to Piedras Blancas in offshore central California using high-resolution seismic reflection profiles, marine magnetic data, and multibeam bathymetry. The database includes 121 seismic profiles across the fault zone and is perhaps the most comprehensive reported survey of the shallow structure of an active strike-slip fault. These data document the location, length, and near-surface continuity of multiple fault strands, highlight fault-zone heterogeneity, and demonstrate the importance of fault trend, fault bends, and fault convergences in the development of shallow structure and tectonic geomorphology. The Hosgri Fault Zone is continuous through the study area passing through a broad arc in which fault trend changes from about 338° to 328° from south to north. The southern ~40 km of the fault zone in this area is more extensional, resulting in accommodation space that is filled by deltaic sediments of the Santa Maria River. The central ~24 km of the fault zone is characterized by oblique convergence of the Hosgri Fault Zone with the more northwest-trending Los Osos and Shoreline Faults. Convergence between these faults has resulted in the formation of local restraining and releasing fault bends, transpressive uplifts, and transtensional basins of varying size and morphology. We present a hypothesis that links development of a paired fault bend to indenting and bulging of the Hosgri Fault by a strong crustal block translated to the northwest along the Shoreline Fault. Two diverging Hosgri Fault strands bounding a central uplifted block characterize the northern ~30 km of the Hosgri Fault in this area. The eastern Hosgri strand passes through releasing and restraining bends; the releasing bend is the primary control on development of an elongate, asymmetric, "Lazy Z" sedimentary basin. The western strand of the Hosgri Fault Zone passes through a significant restraining bend and

  2. Fault tolerant operation of switched reluctance machine

    Science.gov (United States)

    Wang, Wei

    The energy crisis and environmental challenges have driven industry towards more energy efficient solutions. With nearly 60% of electricity consumed by various electric machines in industry sector, advancement in the efficiency of the electric drive system is of vital importance. Adjustable speed drive system (ASDS) provides excellent speed regulation and dynamic performance as well as dramatically improved system efficiency compared with conventional motors without electronics drives. Industry has witnessed tremendous grow in ASDS applications not only as a driving force but also as an electric auxiliary system for replacing bulky and low efficiency auxiliary hydraulic and mechanical systems. With the vast penetration of ASDS, its fault tolerant operation capability is more widely recognized as an important feature of drive performance especially for aerospace, automotive applications and other industrial drive applications demanding high reliability. The Switched Reluctance Machine (SRM), a low cost, highly reliable electric machine with fault tolerant operation capability, has drawn substantial attention in the past three decades. Nevertheless, SRM is not free of fault. Certain faults such as converter faults, sensor faults, winding shorts, eccentricity and position sensor faults are commonly shared among all ASDS. In this dissertation, a thorough understanding of various faults and their influence on transient and steady state performance of SRM is developed via simulation and experimental study, providing necessary knowledge for fault detection and post fault management. Lumped parameter models are established for fast real time simulation and drive control. Based on the behavior of the faults, a fault detection scheme is developed for the purpose of fast and reliable fault diagnosis. In order to improve the SRM power and torque capacity under faults, the maximum torque per ampere excitation are conceptualized and validated through theoretical analysis and

  3. Fault Diagnosis and Fault Tolerant Control with Application on a Wind Turbine Low Speed Shaft Encoder

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Sardi, Hector Eloy Sanchez; Escobet, Teressa

    2015-01-01

    . This sensor has to be correct as blade pitch actions should be different at different azimuth angle as the wind speed varies within the rotor field due to different phenomena. A scheme detecting faults in this sensor has previously been designed for the application of a high end fault diagnosis and fault...... tolerant control of wind turbines using a benchmark model. In this paper, the fault diagnosis scheme is improved and integrated with a fault accommodation scheme which enables and disables the individual pitch algorithm based on the fault detection. In this way, the blade and tower loads are not increased...

  4. Farewell faults in complex fault blocks with multi-technological integration

    Institute of Scientific and Technical Information of China (English)

    YANG Guang-lin; HU Xiao-hui; YAN Jing-hua

    2008-01-01

    In the middle and second half of oilfield development, further exploration and development of petroleum reservoirs in complex fault blocks are major tasks. Based on the characteristics of fully developed farewell faults in the Wenweigu oil field and the data from 3D earthquakes, RFT, HDT and other techniques, farewell faults and their distribution were identified. Conformation of the fault blocks has been provided and the precision of describing the farewell faults improved. Research technology of farewell faults has applied these methods in this region.

  5. A Quaternary Fault Database for Central Asia

    Directory of Open Access Journals (Sweden)

    S. Mohadjer

    2015-09-01

    Full Text Available Earthquakes represent the highest risk in terms of potential loss of lives and economic damage for Central Asian countries. Knowledge of fault location and behavior is essential in calculating and mapping seismic hazard. Previous efforts in compiling fault information for Central Asia have generated a large amount of data that are published in limited-access journals with no digital maps publicly available, or are limited in their description of important fault parameters such as slip rates. This study builds on previous work by improving access to fault information through a web-based interactive map and an online database with search capabilities that allow users to organize data by different fields. The data presented in this compilation include fault location, its geographic, seismic and structural characteristics, short descriptions, narrative comments and references to peer-reviewed publications. The interactive map displays 1196 fault segments and 34 000 earthquake locations on a shaded-relief map. The online database contains attributes for 122 faults mentioned in the literature, with Quaternary and geodetic slip rates reported for 38 and 26 faults respectively, and earthquake history reported for 39 faults. This work has implications for seismic hazard studies in Central Asia as it summarizes important fault parameters, and can reduce earthquake risk by enhancing public access to information. It also allows scientists and hazard assessment teams to identify structures and regions where data gaps exist and future investigations are needed.

  6. A Quaternary Fault Database for Central Asia

    Science.gov (United States)

    Mohadjer, S.; Ehlers, T. A.; Bendick, R.; Stübner, K.; Strube, T.

    2015-09-01

    Earthquakes represent the highest risk in terms of potential loss of lives and economic damage for Central Asian countries. Knowledge of fault location and behavior is essential in calculating and mapping seismic hazard. Previous efforts in compiling fault information for Central Asia have generated a large amount of data that are published in limited-access journals with no digital maps publicly available, or are limited in their description of important fault parameters such as slip rates. This study builds on previous work by improving access to fault information through a web-based interactive map and an online database with search capabilities that allow users to organize data by different fields. The data presented in this compilation include fault location, its geographic, seismic and structural characteristics, short descriptions, narrative comments and references to peer-reviewed publications. The interactive map displays 1196 fault segments and 34 000 earthquake locations on a shaded-relief map. The online database contains attributes for 122 faults mentioned in the literature, with Quaternary and geodetic slip rates reported for 38 and 26 faults respectively, and earthquake history reported for 39 faults. This work has implications for seismic hazard studies in Central Asia as it summarizes important fault parameters, and can reduce earthquake risk by enhancing public access to information. It also allows scientists and hazard assessment teams to identify structures and regions where data gaps exist and future investigations are needed.

  7. Monte Carlo approaches to light nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, J.

    1990-01-01

    Significant progress has been made recently in the application of Monte Carlo methods to the study of light nuclei. We review new Green's function Monte Carlo results for the alpha particle, Variational Monte Carlo studies of {sup 16}O, and methods for low-energy scattering and transitions. Through these calculations, a coherent picture of the structure and electromagnetic properties of light nuclei has arisen. In particular, we examine the effect of the three-nucleon interaction and the importance of exchange currents in a variety of experimentally measured properties, including form factors and capture cross sections. 29 refs., 7 figs.

  8. Monte carlo simulation for soot dynamics

    KAUST Repository

    Zhou, Kun

    2012-01-01

    A new Monte Carlo method termed Comb-like frame Monte Carlo is developed to simulate the soot dynamics. Detailed stochastic error analysis is provided. Comb-like frame Monte Carlo is coupled with the gas phase solver Chemkin II to simulate soot formation in a 1-D premixed burner stabilized flame. The simulated soot number density, volume fraction, and particle size distribution all agree well with the measurement available in literature. The origin of the bimodal distribution of particle size distribution is revealed with quantitative proof.

  9. Lattice gauge theories and Monte Carlo simulations

    CERN Document Server

    Rebbi, Claudio

    1983-01-01

    This volume is the most up-to-date review on Lattice Gauge Theories and Monte Carlo Simulations. It consists of two parts. Part one is an introductory lecture on the lattice gauge theories in general, Monte Carlo techniques and on the results to date. Part two consists of important original papers in this field. These selected reprints involve the following: Lattice Gauge Theories, General Formalism and Expansion Techniques, Monte Carlo Simulations. Phase Structures, Observables in Pure Gauge Theories, Systems with Bosonic Matter Fields, Simulation of Systems with Fermions.

  10. Quantum Monte Carlo for minimum energy structures

    CERN Document Server

    Wagner, Lucas K

    2010-01-01

    We present an efficient method to find minimum energy structures using energy estimates from accurate quantum Monte Carlo calculations. This method involves a stochastic process formed from the stochastic energy estimates from Monte Carlo that can be averaged to find precise structural minima while using inexpensive calculations with moderate statistical uncertainty. We demonstrate the applicability of the algorithm by minimizing the energy of the H2O-OH- complex and showing that the structural minima from quantum Monte Carlo calculations affect the qualitative behavior of the potential energy surface substantially.

  11. Fast quantum Monte Carlo on a GPU

    CERN Document Server

    Lutsyshyn, Y

    2013-01-01

    We present a scheme for the parallelization of quantum Monte Carlo on graphical processing units, focusing on bosonic systems and variational Monte Carlo. We use asynchronous execution schemes with shared memory persistence, and obtain an excellent acceleration. Comparing with single core execution, GPU-accelerated code runs over x100 faster. The CUDA code is provided along with the package that is necessary to execute variational Monte Carlo for a system representing liquid helium-4. The program was benchmarked on several models of Nvidia GPU, including Fermi GTX560 and M2090, and the latest Kepler architecture K20 GPU. Kepler-specific optimization is discussed.

  12. DEM simulation of growth normal fault slip

    Science.gov (United States)

    Chu, Sheng-Shin; Lin, Ming-Lang; Nien, Wie-Tung; Chan, Pei-Chen

    2014-05-01

    Slip of the fault can cause deformation of shallower soil layers and lead to the destruction of infrastructures. Shanchiao fault on the west side of the Taipei basin is categorized. The activities of Shanchiao fault will cause the quaternary sediments underneath the Taipei basin to become deformed. This will cause damage to structures, traffic construction, and utility lines within the area. It is determined from data of geological drilling and dating, Shanchiao fault has growth fault. In experiment, a sand box model was built with non-cohesive sand soil to simulate the existence of growth fault in Shanchiao Fault and forecast the effect on scope of shear band development and ground differential deformation. The results of the experiment showed that when a normal fault containing growth fault, at the offset of base rock the shear band will develop upward along with the weak side of shear band of the original topped soil layer, and this shear band will develop to surface much faster than that of single top layer. The offset ratio (basement slip / lower top soil thickness) required is only about 1/3 of that of single cover soil layer. In this research, it is tried to conduct numerical simulation of sand box experiment with a Discrete Element Method program, PFC2D, to simulate the upper covering sand layer shear band development pace and scope of normal growth fault slip. Results of simulation indicated, it is very close to the outcome of sand box experiment. It can be extended to application in water pipeline project design around fault zone in the future. Keywords: Taipei Basin, Shanchiao fault, growth fault, PFC2D

  13. Computing elastic‐rebound‐motivated rarthquake probabilities in unsegmented fault models: a new methodology supported by physics‐based simulators

    Science.gov (United States)

    Field, Edward H.

    2015-01-01

    A methodology is presented for computing elastic‐rebound‐based probabilities in an unsegmented fault or fault system, which involves computing along‐fault averages of renewal‐model parameters. The approach is less biased and more self‐consistent than a logical extension of that applied most recently for multisegment ruptures in California. It also enables the application of magnitude‐dependent aperiodicity values, which the previous approach does not. Monte Carlo simulations are used to analyze long‐term system behavior, which is generally found to be consistent with that of physics‐based earthquake simulators. Results cast doubt that recurrence‐interval distributions at points on faults look anything like traditionally applied renewal models, a fact that should be considered when interpreting paleoseismic data. We avoid such assumptions by changing the "probability of what" question (from offset at a point to the occurrence of a rupture, assuming it is the next event to occur). The new methodology is simple, although not perfect in terms of recovering long‐term rates in Monte Carlo simulations. It represents a reasonable, improved way to represent first‐order elastic‐rebound predictability, assuming it is there in the first place, and for a system that clearly exhibits other unmodeled complexities, such as aftershock triggering.

  14. GENERAL FAULT ADMITTANCE METHOD LINETO- LINE-TO-LINE UNSYMMETRICAL FAULT

    Directory of Open Access Journals (Sweden)

    J. D. SAKALA

    2015-09-01

    Full Text Available Line-to-line-to-line unsymmetrical faults either involving or not involving ground are in the classical fault analysis approach difficult to analyse. This is because the classical solution requires use of the knowledge of connection of symmetrical component sequence networks for various common faults. In this approach, the phase fault constraints are converted into symmetrical sequence constraints and the sequence networks connected in a way that satisfies the constraints. The symmetrical component constraints for an unsymmetrical three-phase fault not involving ground do not lend themselves easy to the connection of the sequence networks. The exception is that, because the phase currents at the fault summate to zero, the zero sequence current is zero and therefore the zero sequence network is not connected. The connection of the positive and negative sequence networks is difficult to deduce when the fault is unsymmetrical. A classical solution is therefore difficult to find. In contrast, a solution by the general method of fault admittance matrix does not require prior knowledge of how the sequence networks are connected. It is therefore more versatile than the classical methods. The paper presents a procedure for solving a three-phase unsymmetrical fault, with different fault impedances, hence fault admittances in each phase. A computer program based on the general fault admittance method is developed and used to analyse an unsymmetrical three-phase fault on a simple power system with a delta-earthed-star connected transformer.

  15. Active fault survey on the Tanlu fault zone in Laizhou Bay

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-cai; YANG Xi-ha; LI Chang-chuan; DENG Qi-dong; DU Xian-song; CHAO Hong-tai; WU Zi-quan; XIAO Lan-xi; SUN Zhao-ming; MIN Wei; LING Hong

    2006-01-01

    Shallow-depth acoustic reflection profiling survey has been conducted on the Tanlu fault zone in Laizhou Bay. It is found that the Tanlu fault zone is obviously active during the late Quaternary and it is still the dominating structure in this region. The Tanlu fault zone consists of two branches. The KL3 fault of the western branch is composed of several high angle normal faults which had been active during the period from the latest Pleistocene to early Holocene, dissected by a series of northeast or approximate east-west trending fault which leaped sediment of the late Pleistocene. The Longkou fault of the eastern branch consists of two right-laterally stepped segments. Late Quaternary offsets and growth strata developed along the Tanlu fault zone verify that the fault zone retained active in the latest Pleistocene to the early Holocene. The Anqiu-Juxian fault that passes through the middle of Shandong and corresponds to the Longkou fault is composed of a series of right-laterally stepped segments. The active faults along the eastern branch of the Tanlu fault zone from the Laizhou bay to the north of Anqiu make up a dextral simple shear deformation zone which is characterized by right-lateral strike-slip movement with dip-slip component during the late Quaternary.

  16. Active faulting Vs other surface displacing complex geomorphic phenomena. Case studies from a tectonically active area, Abruzzi Region, central Apennines, Italy

    Science.gov (United States)

    Lo Sardo, Lorenzo; Gori, Stefano; Falcucci, Emanuela; Saroli, Michele; Moro, Marco; Galadini, Fabrizio; Lancia, Michele; Fubelli, Giandomenico; Pezzo, Giuseppe

    2016-04-01

    How can be univocally inferred the genesis of a linear surface scarp as the result of an active and capable fault (FAC) in tectonically active regions? Or, conversely, how it is possible to exclude that a scarp is the result of a capable fault activation? Trying to unravel this open questions, we show two ambiguous case studies about the problem of the identification of active and capable faults in a tectonically active area just based on the presence of supposed fault scarps at surface. The selected cases are located in the area comprised between the Middle Aterno Valley Fault (MAVF) and the Campo Imperatore Plain (Abruzzi Region, central Apennines), nearby the epicentral area of the April 6th, 2009 L'Aquila earthquake. In particular, the two case studies analysed are located in a region characterized by a widespread Quaternary faults and by several linear scarps: the case studies of (i) Prata D'Ansidonia area and (ii) Santo Stefano di Sessanio area. To assess the origin and the state of activity of the investigated geomorphic features, we applied a classical geological and geomorphological approach, based on the analysis of the available literature, the interpretation of the aerial photographs, field surveying and classical paleoseismological approach, the latter consisting in digging excavations across the analysed scarps. These analysis were then integrated by morphometrical analyses. As for case (i), we focused on determining the geomorphic "meaning" of linear scarps carved onto fluvial-deltaic conglomerates (dated to the Early Pleistocene; Bertini and Bosi, 1993), up to 3 meters high and up to 1,5 km long, that border a narrow, elongated and flat-bottom depressions, filled by colluvial deposits. These features groove the paleo-landsurface of Valle Daria (Bosi and Bertini, 1970), wide landsurface located between Barisciano and Prata D'Ansidonia. Entwining paleoseismological trenching with geophysical analyses (GPR, ERT and microgravimetrical prospections), it

  17. The Energetics of Gravity Driven Faulting

    Science.gov (United States)

    Barrows, L.

    2007-12-01

    Faulting can result from either of two different mechanisms. These involve fundamentally different energetics. In displacement-bounded faulting, locked-in elastic strain energy is transformed into seismic waves plus work done in the fault zone. Elastic rebound is an example of displacement-bounded faulting. In force-driven faulting, the forces that create the stress on the fault supply work or energy to the faulting process. Half of this energy is transformed into seismic waves plus work done in the fault zone and half goes into an increase in locked-in elastic strain. In displacement-bounded faulting the locked-in elastic strain drives slip on the fault. In force-driven faulting it stops slip on the fault. Tectonic stress is reasonably attributed to gravity acting on topography and the Earth's lateral density variations. This includes the thermal convection that ultimately drives plate tectonics. The gravity collapse seismic mechanism assumes the fault fails and slips in direct response to the gravitational tectonic stress. Gravity collapse is an example of force-driven faulting. In the simplest case, energy that is released from the gravitational potential of the topography and internal stress-causing density variations is equally split between the seismic waves plus work done in the fault zone and the increase in locked-in elastic strain. The release of gravitational potential energy requires a change in the Earth's density distribution. Gravitational body forces are solely dependent on density so a change in the density distribution requires a change in the body forces. This implies the existence of volumetric body-force displacements. The volumetric body-force displacements are in addition to displacements generated by slip on the fault. They must exist if gravity participates in the energetics of the faulting process. From the perspective of gravitational tectonics, the gravity collapse mechanism is direct and simple. The related mechanics are a little more

  18. Surface faulting along the Superstition Hills fault zone and nearby faults associated with the earthquakes of 24 November 1987

    Science.gov (United States)

    Sharp, R.V.

    1989-01-01

    The M6.2 Elmore Desert Ranch earthquake of 24 November 1987 was associated spatially and probably temporally with left-lateral surface rupture on many northeast-trending faults in and near the Superstition Hills in western Imperial Valley. Three curving discontinuous principal zones of rupture among these breaks extended northeastward from near the Superstition Hills fault zone as far as 9km; the maximum observed surface slip, 12.5cm, was on the northern of the three, the Elmore Ranch fault, at a point near the epicenter. Twelve hours after the Elmore Ranch earthquake, the M6.6 Superstition Hills earthquake occurred near the northwest end of the right-lateral Superstition Hills fault zone. We measured displacements over 339 days at as many as 296 sites along the Superstition Hills fault zone, and repeated measurements at 49 sites provided sufficient data to fit with a simple power law. The overall distributions of right-lateral displacement at 1 day and the estimated final slip are nearly symmetrical about the midpoint of the surface rupture. The average estimated final right-lateral slip for the Superstition Hills fault zone is ~54cm. The average left-lateral slip for the conjugate faults trending northeastward is ~23cm. The southernmost ruptured member of the Superstition Hills fault zone, newly named the Wienert fault, extends the known length of the zone by about 4km. -from Authors

  19. Earthquake recurrence on the south Hayward fault is most consistent with a time dependent, renewal process

    Science.gov (United States)

    Parsons, T.

    2008-01-01

    Elastic rebound and stress renewal are important components of earthquake forecasting because if large earthquakes can be shown to be periodic, then rupture probability is time dependent. While renewal models are used in formal forecasts, it has not been possible to exclude the alternate view that repeated large earthquakes can happen in rapid succession without requiring time for stress regeneration. Here a consistency test between time dependent and time independent recurrence distributions is made using a Monte Carlo method to replicate the paleoseismic series on the south Hayward fault. Time dependent distributions with recurrence interval of 210 years and coefficient of variation of 0.6 reproduce the event series on the south Hayward 5 times more often than any exponential distribution: a highly significant difference as determined using a two-tailed Z-test for relative proportions. Therefore large Hayward fault earthquakes are quasi-periodic and are most consistent with a stress renewal process.

  20. 11th International Conference on Monte Carlo and Quasi-Monte Carlo Methods in Scientific Computing

    CERN Document Server

    Nuyens, Dirk

    2016-01-01

    This book presents the refereed proceedings of the Eleventh International Conference on Monte Carlo and Quasi-Monte Carlo Methods in Scientific Computing that was held at the University of Leuven (Belgium) in April 2014. These biennial conferences are major events for Monte Carlo and quasi-Monte Carlo researchers. The proceedings include articles based on invited lectures as well as carefully selected contributed papers on all theoretical aspects and applications of Monte Carlo and quasi-Monte Carlo methods. Offering information on the latest developments in these very active areas, this book is an excellent reference resource for theoreticians and practitioners interested in solving high-dimensional computational problems, arising, in particular, in finance, statistics and computer graphics.

  1. "But since the affairs of men rest still uncertain, let's reason with the worst that may befall": Probability, risk, and the 2009 L'Aquila Earthquake

    CERN Document Server

    Shore, Steven N

    2012-01-01

    This article is a commentary on the verdict of the "L'Aquila Six", the group of bureaucrats and scientists tried by an Italian court as a result of their public statements in advance of the quake of 2009 Apr. 6 that left the city in ruins and cause more than 300 deaths. It was not the worst such catastrophic event in recent Italian history, but it was one of -- if not the -- worst failures of risk assessment and preventive action. The six were found guilty and condemned by a first level of the justice system to substantial prison terms. The outcry provoked by the verdict in the world press and the international scientific community has fueled the already fiery debate over whether the six should have been tried at all. They have been presented as martyrs to science being treated as scapegoats by a scientifically illiterate justice system and inflamed local population for not being able to perform the impossible (predict the event). Petitions of support have been drafted and signed by thousands of working scien...

  2. Detection of Listeria monocytogenes in food samples in Avezzano, Sulmona and Castel di Sangro (province of L'Aquila, Abruzzo, Italy between 2000-2009

    Directory of Open Access Journals (Sweden)

    Nadia Maria Sulli

    2014-09-01

    Full Text Available The retrospective study of the results of the analysed samples is a fundamental tool for the identification of major risk related to food and for planning future monitoring activities. The evaluation of the quality of data collected may also allow for estimating the effectiveness of the controls so to improve their efficacy. In this article, the authors evaluated the results of tests for the detection of Listeria monocytogenes performed by the Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale' (IZSAM on food samples collected during the years 2000-2009 in the territory of Avezzano, Sulmona and Castel di Sangro (province of L'Aquila, Abruzzo, Italy. The comparison of the data examined with those from studies conducted in Italy and in other countries shows that the categories with higher percentages of positivity for Listeria monocytogenes are meat and fish products. Data collected do not indicate cheese as a vehicle of contamination in the sampled areas, in contrast to what reported in the national and international literature. It would therefore be necessary to promote an ad hoc sampling in the areas covered by this study to verify this aspect in more depth.

  3. Gender differences in the relationship between maladaptive behaviours and post-traumatic stress disorder. A study on 900 L’Aquila 2009 earthquake survivors.

    Directory of Open Access Journals (Sweden)

    Liliana eDell'Osso

    2013-01-01

    Full Text Available Background: Post-traumatic stress disorder (PTSD represents one of the most frequently psychiatric sequelae to earthquake exposure. Increasing evidence suggests the onset of maladaptive behaviors among veterans and adolescents with PTSD, with specific gender differences emerging in the latter. Aims of the present study were to investigate the relationships between maladaptive behaviours and PTSD in earthquake survivors, besides the gender differences in the type and prevalence of maladaptive behaviours and their association with PTSD. Methods: 900 residents of the town of L’Aquila who experienced the earthquake of April 6th 2009 (Richter Magnitude 6.3 were assessed by means of the Trauma and Loss Spectrum Self Report (TALS-SR.Results: Significantly higher maladaptive behaviour prevalence rates were found among subjects with PTSD. A statistically significant association was found between male gender and the presence of at least one maladaptive behaviour among PTSD survivors. In the latter, significant correlations emerged between maladaptive coping and symptoms of re-experiencing, avoidance and numbing and arousal in women, while only between maladaptive coping and avoidance and numbing in men. Conclusions: Our results show high rates of maladaptive behaviours among earthquake survivors with PTSD suggesting a greater severity among men. Interestingly, post-traumatic stress symptomatology appears to be a better correlate of these behaviours among women than among men, suggesting the need for further studies based on a gender approach.

  4. Spectral-Timing Analysis of the Lower kHz QPO in the Low-Mass X-ray Binary Aquila X-1

    CERN Document Server

    Troyer, Jon S

    2016-01-01

    Spectral-timing products of kilohertz quasi-periodic oscillations (kHz QPOs) in low-mass X-ray binary (LMXB) systems, including energy- and frequency-dependent lags, have been analyzed previously in 4U 1608-52, 4U 1636-53, and 4U 1728-34. Here, we study the spectral-timing properties of the lower kHz QPO of the neutron star LMXB Aquila X-1 for the first time. We compute broadband energy lags, as well as energy-dependent lags and the covariance spectrum using data from the Rossi X-ray Timing Explorer (RXTE). We find very similar characteristics to other previously studied systems, including soft lags of $\\sim$30 $\\mu$s between the 3.0 - 8.0 keV and 8.0 - 20.0 keV energy bands at the average QPO frequency. We also find lags that show a nearly monotonic trend with energy, with the highest energy photons arriving first. The covariance spectrum of the lower kHz QPO is well fit by a thermal Comptonization model, though we find a higher seed photon temperature compared to the mean spectrum, which was also seen in Pe...

  5. Neural correlates of automatic perceptual sensitivity to facial affect in posttraumatic stress disorder subjects who survived L'Aquila eartquake of April 6, 2009.

    Science.gov (United States)

    Mazza, Monica; Catalucci, Alessia; Mariano, Melania; Pino, Maria Chiara; Tripaldi, Simona; Roncone, Rita; Gallucci, Massimo

    2012-09-01

    The "Emotional Numbing" (EN) constitutes one of the core symptoms in PTSD although its exact nature remains elusive. This disorder shows an abnormal response of cortical and limbic regions which are normally involved in understanding emotions since the very earliest stages of the development of processing ability. The aim of our study, which included ten physically healthy subjects with PTSD, diagnosed according to DSM-IV-TR, who survived L'Aquila earthquake of April 6, 2009, and 10 healthy controls matching for age, sex and education, was to examine automatic perceptual sensitivity to facial affect in PTSD, through an affective priming task that was administered during functional magnetic resonance (fMRI). Behavioural data revealed in the PTSD group a higher sensitivity to negative facial affect on an automatic processing level. FMRI data analysis revealed that PTSD subjects showed a significantly higher activation in right insula and left amygdala that we did not observe in healthy subjects; on the contrary, healthy controls showed a greater activation of left lingual gyrus. Our data support the hypothesis that PTSD appears to be sensitive to negative affect on an automatic processing level and correlates with the activation of specific areas involved in processing emotions. An elevated activation of these areas may underlie the emotion dysregulation in PTSD and could explain the Emotional Numbing symptom associated with this disorder. The present study suffers of a number of limitations, for instance, the relatively small sample size did not allow the application of alternative statistical models.

  6. Burnout among therapists working with persons with autism after the 2009 earthquake in L'Aquila, Italy: a longitudinal comparative study.

    Science.gov (United States)

    Valenti, M; La Malfa, G; Tomassini, A; Masedu, F; Tiberti, S; Sorge, G

    2014-04-01

    The aim of this study was to follow up the occurrence of burnout in therapists of children and adolescents with autism experiencing the 2009 earthquake in L'Aquila, and to discuss implications for burnout prevention after disasters. A longitudinal study was carried out, measuring burnout outcomes according to the Maslach Burnout Inventory in 11 exposed and 53 unexposed therapists. Staff in the exposed group appeared to report significantly higher levels of emotional exhaustion after 1 and 2 years of follow-up than the unexposed staff. As to lack of personal accomplishment, the exposed groups shows increasingly lower scores with respect to the unexposed group, with personal accomplishment (PA) values falling from 41.0 [standard deviation (SD) 3.7] to 33.4 (SD 4.1) after 2 years, whereas PA values remain stable over time in the unexposed group. As to depersonalization, data show no significant difference between groups. Burnout occurrence is induced by the exceptional stressors related with natural disasters like earthquakes. Efforts are required to help mental health workers, including psychiatric nurses, to cope with the devastating situation determined by an earthquake. A periodical monitoring of mental health status is recommended in mental health works, especially with regard to help with post-traumatic stress disorder, coping with work and therapeutic relationships, family and social life and economic impact.

  7. Non-permanent GPS data for regional-scale kinematics: reliable deformation rate before the 6 April, 2009, earthquake in the L'Aquila area

    Directory of Open Access Journals (Sweden)

    Fabiana Loddo

    2010-05-01

    Full Text Available A GPS-based geodetic study at a regional scale requires the availability of a dense network that is characterized by 10 km to 30 km spacing, typically followed in a few continuous GPS stations (CGPSs and several non-permanent GPS stations (NPSs. As short observation times do not allow adequate noise modeling, NPS data need specific processing where the main differences between NPSs and CGPSs are taken into account: primarily time-series length and antenna repositioning error. The GPS data collected in the 1999-2007 time-span from non-permanent measurement campaigns in the central Apennine area (Italy that was recently hit by the Mw 6.3 L'Aquila earthquake (April 6, 2009 are here further analyzed to compute a reliable strain-rate field at a regional scale. Moreover, areas characterized by different kinematics are recognized, and a complete characterization of the regional-scale kinematics is attempted. These new data can be interpreted as indicators from the viewpoint of seismic risk assessment.

  8. Recent seismicity of Italy: Active tectonics of the central Mediterranean region and seismicity rate changes after the Mw 6.3 L'Aquila earthquake

    Science.gov (United States)

    Chiarabba, Claudio; De Gori, Pasquale; Mele, Francesco Mariano

    2015-01-01

    In this paper we present a new image of the instrumental seismicity of Italy, obtained by refining hypocentral determinations for about 100,000 earthquakes that occurred in the period 2005-2012. The improved locations yield new constraints on active tectonics of the central Mediterranean area, where prolonged interaction between nested plates and continental slivers led to the development of the Alpine and Apennines systems. Intermediate-depth and deep earthquakes define a lateral heterogeneous process of delamination and sinking of the continental lithosphere active beneath the mountain belts. Shallow seismicity prevalently occurs beneath elevated topography and correlates with low velocity mantle anomalies, suggesting a superposition of gravity-related forces to the Eurasia-Africa plate convergence. The delamination process drives a paired system of compression and extension that stretches the mountain range while shortening the external side of the belts. The updated seismic catalog permits us to resolve a sharp variation of seismic rates that occurred in recent years, timely after the 2009 Mw 6.3 L'Aquila earthquake. The increase of seismic rates is reasonably due to regional-scale perturbation of the stress field induced by fluid flow and pore-pressure variations within the crust, probably related to deep dehydration processes active beneath the mountain belt.

  9. On a reported effect in ionospheric TEC around the time of the 6 April 2009 L'Aquila earthquake

    Directory of Open Access Journals (Sweden)

    F. Masci

    2017-09-01

    Full Text Available In a report published in Advances in Space Research, Nenovski et al. (2015 analyse ionospheric TEC (total electron content data from GPS measurements around the time of the 6 April 2009 Mw 6. 1 L'Aquila (Italy earthquake. According to the authors, TEC difference (DTEC calculated from two GPS (Global Positioning System receivers in central Italy shows a hump-like shape (an increase followed by a decrease during the hours just before and shortly after the main shock. They maintain that the hump-like shape is anomalous and may be related to the earthquake. We show that the DTEC increase in the hours before the shock, as well as its subsequent slow decrease, does not have any characteristic that might support a possible relationship with the earthquake. We have also conducted our own independent analysis using the same GPS data analysed by Nenovski et al. (2015. We have found a diurnal variation in DTEC time series that shows hump-like shapes like that reported by Nenovski et al. (2015 throughout the investigated period. This demonstrates that the hump-like shape in DTEC close to the time of the 6 April earthquake is not anomalous and cannot be considered a possible earthquake-related effect.

  10. Gender Differences in the Relationship between Maladaptive Behaviors and Post-Traumatic Stress Disorder. A Study on 900 L' Aquila 2009 Earthquake Survivors.

    Science.gov (United States)

    Dell'osso, Liliana; Carmassi, Claudia; Stratta, Paolo; Massimetti, Gabriele; Akiskal, Kareen K; Akiskal, Hagop S; Maremmani, Icro; Rossi, Alessandro

    2012-01-01

    Post-traumatic stress disorder (PTSD) represents one of the most frequently psychiatric sequelae to earthquake exposure. Increasing evidence suggests the onset of maladaptive behaviors among veterans and adolescents with PTSD, with specific gender differences emerging in the latter. Aims of the present study were to investigate the relationships between maladaptive behaviors and PTSD in earthquake survivors, besides the gender differences in the type and prevalence of maladaptive behaviors and their association with PTSD. 900 residents of the town of L'Aquila who experienced the earthquake of April 6th 2009 (Richter Magnitude 6.3) were assessed by means of the Trauma and Loss Spectrum-Self Report (TALS-SR). Significantly higher maladaptive behavior prevalence rates were found among subjects with PTSD. A statistically significant association was found between male gender and the presence of at least one maladaptive behavior among PTSD survivors. Further, among survivors with PTSD significant correlations emerged between maladaptive coping and symptoms of re-experiencing, avoidance and numbing, and arousal in women, while only between maladaptive coping and avoidance and numbing in men. Our results show high rates of maladaptive behaviors among earthquake survivors with PTSD suggesting a greater severity among men. Interestingly, post-traumatic stress symptomatology appears to be a better correlate of these behaviors among women than among men, suggesting the need for further studies based on a gender approach.

  11. Gender Differences in the Relationship between Maladaptive Behaviors and Post-Traumatic Stress Disorder. A Study on 900 L’ Aquila 2009 Earthquake Survivors

    Science.gov (United States)

    Dell’Osso, Liliana; Carmassi, Claudia; Stratta, Paolo; Massimetti, Gabriele; Akiskal, Kareen K.; Akiskal, Hagop S.; Maremmani, Icro; Rossi, Alessandro

    2013-01-01

    Background: Post-traumatic stress disorder (PTSD) represents one of the most frequently psychiatric sequelae to earthquake exposure. Increasing evidence suggests the onset of maladaptive behaviors among veterans and adolescents with PTSD, with specific gender differences emerging in the latter. Aims of the present study were to investigate the relationships between maladaptive behaviors and PTSD in earthquake survivors, besides the gender differences in the type and prevalence of maladaptive behaviors and their association with PTSD. Methods: 900 residents of the town of L’Aquila who experienced the earthquake of April 6th 2009 (Richter Magnitude 6.3) were assessed by means of the Trauma and Loss Spectrum-Self Report (TALS-SR). Results: Significantly higher maladaptive behavior prevalence rates were found among subjects with PTSD. A statistically significant association was found between male gender and the presence of at least one maladaptive behavior among PTSD survivors. Further, among survivors with PTSD significant correlations emerged between maladaptive coping and symptoms of re-experiencing, avoidance and numbing, and arousal in women, while only between maladaptive coping and avoidance and numbing in men. Conclusions: Our results show high rates of maladaptive behaviors among earthquake survivors with PTSD suggesting a greater severity among men. Interestingly, post-traumatic stress symptomatology appears to be a better correlate of these behaviors among women than among men, suggesting the need for further studies based on a gender approach. PMID:23293608

  12. Aasta film - joonisfilm "Mont Blanc" / Verni Leivak

    Index Scriptorium Estoniae

    Leivak, Verni, 1966-

    2002-01-01

    Eesti Filmiajakirjanike Ühing andis aasta 2001 parima filmi tiitli Priit Tenderi joonisfilmile "Mont Blanc" : Eesti Joonisfilm 2001.Ka filmikriitikute eelistused kinodes ja televisioonis 2001. aastal näidatud filmide osas

  13. Simulation and the Monte Carlo method

    CERN Document Server

    Rubinstein, Reuven Y

    2016-01-01

    Simulation and the Monte Carlo Method, Third Edition reflects the latest developments in the field and presents a fully updated and comprehensive account of the major topics that have emerged in Monte Carlo simulation since the publication of the classic First Edition over more than a quarter of a century ago. While maintaining its accessible and intuitive approach, this revised edition features a wealth of up-to-date information that facilitates a deeper understanding of problem solving across a wide array of subject areas, such as engineering, statistics, computer science, mathematics, and the physical and life sciences. The book begins with a modernized introduction that addresses the basic concepts of probability, Markov processes, and convex optimization. Subsequent chapters discuss the dramatic changes that have occurred in the field of the Monte Carlo method, with coverage of many modern topics including: Markov Chain Monte Carlo, variance reduction techniques such as the transform likelihood ratio...

  14. Avariide kiuste Monte Carlosse / Aare Arula

    Index Scriptorium Estoniae

    Arula, Aare

    2007-01-01

    Vt. ka Tehnika dlja Vsehh nr. 3, lk. 26-27. 26. jaanuaril 1937 Tallinnast Monte Carlo tähesõidule startinud Karl Siitanit ja tema meeskonda ootasid ees seiklused, mis oleksid neile peaaegu elu maksnud

  15. Avariide kiuste Monte Carlosse / Aare Arula

    Index Scriptorium Estoniae

    Arula, Aare

    2007-01-01

    Vt. ka Tehnika dlja Vsehh nr. 3, lk. 26-27. 26. jaanuaril 1937 Tallinnast Monte Carlo tähesõidule startinud Karl Siitanit ja tema meeskonda ootasid ees seiklused, mis oleksid neile peaaegu elu maksnud

  16. Monte Carlo simulations for plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, M.; Murakami, S.; Nakajima, N.; Wang, W.X. [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2000-07-01

    Plasma behaviours are very complicated and the analyses are generally difficult. However, when the collisional processes play an important role in the plasma behaviour, the Monte Carlo method is often employed as a useful tool. For examples, in neutral particle injection heating (NBI heating), electron or ion cyclotron heating, and alpha heating, Coulomb collisions slow down high energetic particles and pitch angle scatter them. These processes are often studied by the Monte Carlo technique and good agreements can be obtained with the experimental results. Recently, Monte Carlo Method has been developed to study fast particle transports associated with heating and generating the radial electric field. Further it is applied to investigating the neoclassical transport in the plasma with steep gradients of density and temperatures which is beyong the conventional neoclassical theory. In this report, we briefly summarize the researches done by the present authors utilizing the Monte Carlo method. (author)

  17. Predator trapping on Monte Vista NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This letter is summarizing the status of predator trapping on Monte Vista National Wildlife refuge in light of the referendum passes in the State of Colorado banning...

  18. Quantum Monte Carlo Calculations of Light Nuclei

    CERN Document Server

    Pieper, Steven C

    2007-01-01

    During the last 15 years, there has been much progress in defining the nuclear Hamiltonian and applying quantum Monte Carlo methods to the calculation of light nuclei. I describe both aspects of this work and some recent results.

  19. Improved Monte Carlo Renormalization Group Method

    Science.gov (United States)

    Gupta, R.; Wilson, K. G.; Umrigar, C.

    1985-01-01

    An extensive program to analyze critical systems using an Improved Monte Carlo Renormalization Group Method (IMCRG) being undertaken at LANL and Cornell is described. Here we first briefly review the method and then list some of the topics being investigated.

  20. Monte Carlo methods for particle transport

    CERN Document Server

    Haghighat, Alireza

    2015-01-01

    The Monte Carlo method has become the de facto standard in radiation transport. Although powerful, if not understood and used appropriately, the method can give misleading results. Monte Carlo Methods for Particle Transport teaches appropriate use of the Monte Carlo method, explaining the method's fundamental concepts as well as its limitations. Concise yet comprehensive, this well-organized text: * Introduces the particle importance equation and its use for variance reduction * Describes general and particle-transport-specific variance reduction techniques * Presents particle transport eigenvalue issues and methodologies to address these issues * Explores advanced formulations based on the author's research activities * Discusses parallel processing concepts and factors affecting parallel performance Featuring illustrative examples, mathematical derivations, computer algorithms, and homework problems, Monte Carlo Methods for Particle Transport provides nuclear engineers and scientists with a practical guide ...