Multi-scale seismic hazard scenarios

2011/2012Seismic hazard assessment can be performed following a neo-deterministic approach (NDSHA), which allows to give a realistic description of the seismic ground motion due to an earthquake of given distance and magnitude. The approach is based on modelling techniques that have been developed from a detailed knowledge of both the seismic source process and the propagation of seismic waves. This permits to define a set of earthquake scenarios and to simulate the associated synthetic signals without having to wait for a strong event to occur. NDSHA can be applied at different geographic scale with different detail levels of modelling. At local scale the source and site characteristics can be take account, whereas at the regional scale seismograms at the nodes of a regular grid are computed. Finite fault simulation is needed to compute realistic ground motions close to a ruptured fault. No reasonable deterministic prediction for many details of a future fault motion can be expected and their variability can be treated in practice only from a statistical viewpoint. Therefore, their effect is simulated through Monte-Carlo approach. To test the accuracy of the method, the L’Aquila earthquake occurred on April 6, 2009 has been modelled. The use of a realistic model for the representation of the extended fault introduces a stochastic element in NDSHA. So the variability due to the stochastic component of seismic source has been evaluated. In standard NDSHA at regional scale, seismograms are computed for an upper frequency content of 1 Hz. The use of a more realistic source model than the scaled point source that takes account of effective duration of rupture process allowed to extend the maximum frequency of computation of seismograms of national scale maps to 10 Hz. A first estimation of uncertainty due to the random representation of the source in national scale maps has been obtained by parametric tests on EU-India Grid infrastructure. NDSHA defines the hazard as the maximum ground motion at the site and it does not supply information about the frequency of occurrence of the expected ground motion. The standard procedure of NDSHA has been modified here, to take into account the additional information of recurrence. The introduction of recurrence estimates in NDSHA allows the generation of ground motion maps for specified return periods that permits a straightforward comparison between the NDSHA and the PSHA maps. Furthermore the map of the recurrence has been associated with standard map of ground motion.La valutazione della pericolosità sismica può essere effettuata seguendo un approccio neo-deterministico (NDSHA) che permette di dare una descrizione realistica del moto del suolo dovuto a un terremoto di data distanza e magnitudo. L’approccio è basato su tecniche di modellazione che sono state sviluppate da una conoscenza dettagliata sia della sorgente che della propagazione delle onde sismiche. Questo permette di definire un set di terremoti di scenario e di simulare i segnali sintetici associati senza dover aspettare l’accadimento di un forte evento. La metodologia neo-deterministica può essere applicata a diverse scale geografiche cui corrispondono differenti livelli di dettaglio nella modellazione. A scala locale è possibile tenere conto delle caratteristiche specifiche della sorgente e del sito considerati, mentre a scala regionale vengono calcolati i sismogrammi ai nodi di una griglia regolare. Per simulare in modo realistico il moto del suolo in prossimità di una faglia è necessario usare un modello di sorgente estesa. Molti dettagli del processo di rottura sulla sorgente non possono essere predetti in modo deterministico e la loro variabilità può essere trattata solo da un punto di vista statistico. Di conseguenza i loro effetti vengono simulati attraverso una approccio Monte-Carlo. Per testare l’accuratezza del metodo è stato modellato il terremoto dell’Aquila del 6 aprile 2009. L’uso di un modello realistico di sorgente per la rappresentazione della sorgente estesa introduce un elemento stocastico nel metodo neo-deterministico. Si è quindi valutata la variabilità dei valori di picco dovuta alla modellazione della sorgente. Nella metodologia neo-deterministica scala regionale i sismogrammi vengono calcolati con una frequenza massima di 1 Hz. L’uso di un modello di sorgente piu` realistico rispetto a quello della sorgente puntiforme in grado di tener in conto dell’effettiva durata del processo di rottura ha consentito di estendere la frequenza massima di calcolo dei sismogrammi delle mappe di pericolosità nazionali a 10 Hz. Una prima stima dell’incertezza legata alla simulazione stocastica della sorgente sulle mappe a scala nazionale è stata ottenuta con l’uso di test parametrici condotti utilizzando l’infrastruttura informatica EU-India Grid. Il metodo neo-deterministico definisce la pericolosità come il massimo scuotimento al sito e non fornisce alcuna informazione sulla ricorrenza del moto del suolo atteso. La procedura è stata modificata per tener conto dell’informazione aggiuntiva della ricorrenza. In questo modo è stato possibile generare delle mappe di scuotimento per specifici periodi di ritorno che consentono un diretto confronto con le mappe probabilistiche. Inoltre alle mappe di massimo scuotimento sono state associate le rispettive mappe di ricorrenza del moto del suolo.XXV Ciclo198

Preliminary Neo-Deterministic Seismic Hazard Assessment in Pakistan and Adjoining Regions

The regional seismic hazard in Pakistan and adjoining regions is assessed using the Neo-deterministic seismic hazard assessment approach (NDSHA). Synthetic seismograms are generated by the modal summation technique at the nodes of a grid that covers the studied area. The main input for the computations consists of a set of earthquake sources and of the structural model where the seismic waves propagate. The earthquake sources are parameterised within the active seismogenic areas by defining the focal mechanism, the depth and the magnitude, obtained through the analysis and re- elaboration of the past seismicity. The peak displacement (Dmax), peak velocity (Vmax) and design ground acceleration (DGA) are then extracted from the synthetic signals and plotted on the 0.2\ub0 x 0.2\ub0 grid to construct the seismic hazard map of the studied area. There are few probabilistic hazard maps available for Pakistan, however, this is the first study aimed at producing a neo-deterministic seismic hazard map for Pakistan and adjoining regions.The most severe hazard is found in the epicentral zone of the great Muzaffarabad earthquakes of 2005 and its surroundings, where the DGA estimate falls in the highest range 0.60 g \u2013 1.2 g. The peak velocity and displacement in the same region are estimated as 60 12120 cm s 121 and 30 1260 cm, respectively

A seismological and engineering perspective on the 2016 Central Italy earthquakes

The strong earthquake (M 6.0-6.2) that hit the central Apennines on August 24, 2016, occurred in one of the most seismically active areas in Italy. Field surveys indicated severe damage in the epicentral area where, in addition to the loss of human life, widespread destruction of cultural heritage and of critical buildings occurred. Using the neo-deterministic seismic hazard assessment (NDSHA), we apply the maximum deterministic seismic input (MDSI) procedure at two of the most relevant sites in the epicentral area, comparing the results with the current Italian building code. After performing an expeditious engineering analysis, we interpret as a possible cause of the reported damages the high seismic vulnerability of the built environment, combined with the source and site effects characterising the seismic input. Therefore, it is important to design and retrofit with appropriate spectral acceleration levels compatible with the possible future scenarios, like the ones provided by MDSI

Combining LoRaWAN and a New 3D Motion Model for Remote UAV Tracking

Over the last few years, the many uses of Unmanned Aerial Vehicles (UAVs) have captured the interest of both the scientific and the industrial communities. A typical scenario consists in the use of UAVs for surveillance or target-search missions over a wide geographical area. In this case, it is fundamental for the command center to accurately estimate and track the trajectories of the UAVs by exploiting their periodic state reports. In this work, we design an ad hoc tracking system that exploits the Long Range Wide Area Network (LoRaWAN) standard for communication and an extended version of the Constant Turn Rate and Acceleration (CTRA) motion model to predict drone movements in a 3D environment. Simulation results on a publicly available dataset show that our system can reliably estimate the position and trajectory of a UAV, significantly outperforming baseline tracking approaches.Comment: 6 pages, 6 figures, in review for IEEE WISARN 2020 (INFOCOM WORKSHOP) 2020 : IEEE WiSARN 2020 (INFOCOM WORKSHOP) 2020: 13th International Workshop on Wireless Sensor, Robot and UAV Network

Effect of the number of daily distributions of solid feed on veal calves' health status, behaviour, and alterations of rumen and abomasa

The research aimed at evaluating the effect of three versus two daily distributions of solid feed on veal calves' health, behaviour, and rumen and abomasal mucosa alterations with the rationale that three distributions might improve calves' health and welfare. The study was carried out in two veal calf farms that provided different amounts of solid feed (farm A 200 kg DM/calf; farm B 150 kg DM/calf) during the fattening in addition to liquid milk-replacer. It involved 342 calves in farm A and 108 calves in farm B. The change from two to three solid feed distributions/day started for half calves/farm after the third month of fattening when farm A was feeding 800 g and farm B 600 g DM/calf/day. Health status, blood haemoglobin, and behaviour were assessed on farm at different times. Calves' carcass weight was recorded and rumens and abomasa were inspected post mortem. Increasing solid feed distributions did not improve calves' health but it reduced non-nutritive oral behaviours (4.8 versus 3.2 ± 0.4% for two and three distributions/day, respectively) by prolonging the time spent eating solid feed. Carcass weight was similar between treatments. Three daily solid feed distributions did not reduce the prevalence of rumen mucosa hyperkeratinisation and abomasal alterations, worsening the frequency of rumen plaques. As the partition of daily dose of solid feed in three distributions is more time and labour consuming, its benefits addressing only the reduction of non-nutritive oral behaviours seem not sufficient to justify the routinely adoption of this practice by veal producers

Tau protein modulates an epigenetic mechanism of cellular senescence in human SH-SY5Y neuroblastoma cells

Introduction: Progressive Tau deposition in neurofibrillary tangles and neuropil threads is the hallmark of tauopathies, a disorder group that includes Alzheimer’s disease. Since Tau is a microtubule-associated protein, a prevalent concept to explain the pathogenesis of tauopathies is that abnormal Tau modification contributes to dissociation from microtubules, assembly into multimeric β-sheets, proteotoxicity, neuronal dysfunction and cell loss. Tau also localizes in the cell nucleus and evidence supports an emerging function of Tau in DNA stability and epigenetic modulation.Methods: To better characterize the possible role of Tau in regulation of chromatin compaction and subsequent gene expression, we performed a bioinformatics analysis of transcriptome data obtained from Tau-depleted human neuroblastoma cells.Results: Among the transcripts deregulated in a Tau-dependent manner, we found an enrichment of target genes for the polycomb repressive complex 2. We further describe decreased cellular amounts of the core components of the polycomb repressive complex 2 and lower histone 3 trimethylation in Tau deficient cells. Among the de-repressed polycomb repressive complex 2 target gene products, IGFBP3 protein was found to be linked to increased senescence induction in Tau-deficient cells.Discussion: Our findings propose a mechanism for Tau-dependent epigenetic modulation of cell senescence, a key event in pathologic aging

SHARK-NIR, the coronagraphic camera for LBT, moving toward construction

SHARK-NIR is one of the two coronagraphic instruments proposed for the Large Binocular Telescope. Together with SHARK-VIS (performing coronagraphic imaging in the visible domain), it will offer the possibility to do binocular observations combining direct imaging, coronagraphic imaging and coronagraphic low resolution spectroscopy in a wide wavelength domain, going from 0.5{\mu}m to 1.7{\mu}m. Additionally, the contemporary usage of LMIRCam, the coronagraphic LBTI NIR camera, working from K to L band, will extend even more the covered wavelength range. In January 2017 SHARK-NIR underwent a successful final design review, which endorsed the instrument for construction and future implementation at LBT. We report here the final design of the instrument, which foresees two intermediate pupil planes and three focal planes to accomodate a certain number of coronagraphic techniques, selected to maximize the instrument contrast at various distances from the star. Exo-Planets search and characterization has been the science case driving the instrument design, but the SOUL upgrade of the LBT AO will increase the instrument performance in the faint end regime, allowing to do galactic (jets and disks) and extra-galactic (AGN and QSO) science on a relatively wide sample of targets, normally not reachable in other similar facilities.Comment: 8 pages, 6 figures, AO4ELT5 conference proceeding