Bringing Semantic Services to Real World Objects

The last few years have seen the emergence of two parallel trends: the first of such trends is set by technologies such as Near Field Communication, 2D Bar codes and RFID that support the association of digital information with virtually every object. By using these technologies, ordinary objects such as coffee mugs or advertisement posters provide digital information that can be easily processed. The second trend is set by (semantic) Web services that provide a way to automatically invoke functionalities across the Internet lowering interoperability barriers. The PERCI system, discussed in the article, provides a bridge between these two technologies allowing the invocation of Web services using the information gathered from the tags to effectively transform every object in a service proxy.</p

Dynamic characterization of soils by means seismic passive measures and their utility in Seismic Microzonation studies

RIASSUNTO Le vibrazioni ambientali contengono informazioni sulla struttura di velocità delle onde di taglio nel sottosuolo che può essere stimata dalla curva di dispersione delle velocità di fase delle onde di Rayleigh ottenuta mediante le misure di array sismico. La curva dei rapporti spettrali H/V (o HVSR) ottenuta dalle misure a stazione singola fornisce una stima diretta della frequenza di risonanza del sito e contiene informazioni sulla velocità media delle onde S e sullo spessore totale della copertura sedimentaria. Entrambe le curve possono essere utilizzate in una procedura di inversione congiunta con lo scopo di ottenere un profilo di VS del sottosuolo più dettagliato. L’uso di queste tecniche di sismica passiva finalizzate alla caratterizzazione dinamica dei terreni sta crescendo significativamente negli ultimi anni e, in particolare, la loro applicazione nel contesto degli studi di Microzonazione Sismica sta diventando di fondamentale importanza. Questa tesi di dottorato è caratterizzata da una natura applicativa. I suoi scopi principali sono stati: • verificare e valutare l’affidabilità delle tecniche di sismica passiva in presenza di una marcata inversione di velocità delle onde S nel sottosuolo; • verificare la capacità informativa dell’uso estensivo di tali metodi, identificando anche le eterogeneità geologiche laterali alla scala che va dalle centinaia di metri alle decine di chilometri. Gli obiettivi e le linee di ricerca trattati in questa tesi sono finalizzati a migliorare il potenziale informativo delle misure di sismica passiva per scopi connessi agli studi di Microzonazione Sismica. I primi tre Capitoli sono dedicati alla rassegna dello stato dell’arte riguardante l’origine e la natura delle vibrazioni ambientali e le differenti procedure di analisi adottate per le misure a stazione singola e per quelle di array sismico. Inoltre, nel Capitolo 4 è stata fornita una rassegna dei metodi finalizzati alla stima del profilo di VS, comprendente sia gli approcci semplificati, sia le più comuni procedure di inversione. Per conseguire il primo scopo del lavoro, è stato realizzato uno studio nell’Arcipelago Maltese, dove la stratigrafia dei siti indagati è caratterizzata dalla presenza di uno spesso strato sepolto a bassa velocità delle onde S. Questa configurazione geologica è chiaramente visibile in affioramento e facilmente deducibile consultando la carta geologica. Questo studio ha dimostrato l’ottima capacità delle tecniche di sismica passiva e della procedura di inversione congiunta basata sugli Algoritmi Genetici nel determinare sia la presenza che le caratteristiche dello strato a bassa velocità nel sottosuolo. Inoltre, è stato mostrato che la curva di dispersione effettiva delle velocità delle onde di Rayleigh ottenuta attraverso il metodo ESAC rappresenta un eccellente indicatore per identificare questa particolare configurazione di sottosuolo. Per quanto riguarda il secondo obiettivo della tesi, nel Capitolo 6 sono stati mostrati e analizzati i risultati di un utilizzo estensivo delle prospezioni di simica passiva effettuate nell’area danneggiata dalla sequenza sismica di Maggio-Giugno 2012 in Emilia Romagna (Italia Settentrionale). L’ispezione visuale delle curve HVSR ha permesso di identificare tre zone dove è attesa la stessa risposta sismica. Nonostante gli andamenti generali delle curve siano effetto della configurazione del sottosuolo, i rapporti spettrali H/V mostrano una significativa dipendenza alle condizioni meteo-climatiche: in particolare, le ampiezze dei picchi in bassa frequenza (< 0.5 Hz) sono significativamente correlate con l’attività delle onde del mare nel Mediterraneo Centrale. Tuttavia, le frequenze di risonanza stimate dai picchi HVSR appaiono persistenti e sono state usate per stimare la profondità dei contrasti di impedenza responsabili dei fenomeni di risonanza sismica individuati. A questo scopo, sono stati stimati i valori di VS media usando una procedura semplificata vincolata dalle curve di dispersione delle onde di Rayleigh ricavate dagli array sismici. In questo modo, sono state individuate due interfacce principali, una alla profondità di 50-100 m e l’altra a 500-600 m. Infine, con lo scopo di effettuare un’identificazione automatica delle aree a larga scala individuate da curve HVSR simili, nel Capitolo 7 è stata proposta una procedura basata sull’Analisi delle Componenti Principali (PCA). Dopo aver definito i criteri di raggruppamento, è stato osservato che questa tecnica è in grado di raggruppare insieme simili curve H/V, ottenendo in questo modo una prima identificazione delle eterogeneità a larga scala dell’area di studio. Un’altra caratteristica significativa della PCA è l’immediato riconoscimento dei pattern principali che rappresentano la varianza complessiva del dataset originale. Inoltre, i casi studio analizzati dimostrano che questa tecnica e le procedure di raggruppamento adottate discriminano particolarmente bene le eterogeneità a larga scala in contesti caratterizzati da variazioni geologiche significative. ABSTRACT Ambient vibrations contain information on the local S-wave velocity structure, which can be obtained from the Rayleigh wave phase velocity dispersion curve by means of seismic array measurements. The horizontal-to-vertical (HVSR or H/V) spectral ratio from single stations provides a direct estimate of the soil resonance frequency and also contains information on the average S-wave velocity and the total thickness of the sedimentary cover. Both curves can be used in a joint inversion procedure in order to obtain a more detailed VS profile of the subsoil. The use of these passive seismic techniques for dynamic characterization of soils is significantly growing in the last few years and, in particular, their application in the framework of Seismic Microzonation studies is becoming of paramount importance. This PhD thesis is characterized by an applicative nature. Its main goals were: • to verify and evaluate the reliability of the passive seismic techniques in presence of a significant S-wave velocity inversion in the subsoil; • to check the informative capability of the extensive use of the ambient vibration prospecting, also identifying the lateral geological heterogeneities at the scale ranging from hundreds of meters to tens of kilometers. The objectives and the research lines dealt in this dissertation are devoted to improve the informative potential of the passive seismic measurements for purposes related to Seismic Microzonation studies. The first three Chapters of the thesis were devoted to review the state of the art concerning the origin and the nature of the ambient vibrations and the different analysis procedures adopted for the single station and seismic array measurements. Moreover, in the Chapter 4 a review of the methods aimed to estimate the VS profile was given, both concerning the simplified approaches and the most common inversion procedures. In order to accomplish the first purpose of the dissertation, a study is carried out in the Maltese Archipelago, where the stratigraphy of the investigated sites is characterized by the presence of a thick buried low S-wave velocity layer. This geological setting is clearly visible in outcropping and easily deduced by using the geological map. This study is showed in Chapter 5 and it demonstrated the optimal capability of the passive seismic techniques and the joint inversion procedure based on Genetic Algorithms in resolving both the presence and the characteristics of the thick buried low-velocity layer in the stratigraphy. Moreover, it has been shown that the effective Rayleigh wave dispersion curves obtained using the ESAC method represents an excellent marker to identify this particular subsoil characteristic. As concerns the second objective of this thesis, the results of an extensive use of the ambient vibration prospecting carried out in the area damaged by May-June 2012 seismic sequence in Emilia Romagna (Northern Italy) are summarized and analyzed in Chapter 6. The visual inspection of the HVSR curves allowed to identify three zones where analogous seismic response is expected. Despite the fact these general trends are the effect of the subsoil configuration, H/V spectral ratios show a significant dependence on meteo-climatic conditions: in particular, HVSR peak amplitudes in the low frequency range (< 0.5 Hz) correlate significantly with the sea wave activity in the Central Mediterranean. Anyway, resonance frequencies estimated from HVSR peaks appear persistent and have been used to estimate the local depth of impedance contrasts responsible for seismic resonance phenomena. To this purpose, average VS values were assessed using a simplified procedure constrained by Rayleigh dispersion curves deduced from the seismic arrays. In this way, two main interfaces have been detected: at depths of about 50–100 and 500–600 m. Finally, in order to perform an automatic identification of the large scale areas detected by similar HVSR curves, a procedure based on Principal Component Analysis (PCA) was proposed in Chapter 7. After defining the grouping criteria, It was observed that this technique is able to group together similar HVSR curves, obtaining in this way a first identification of the large scale heterogeneities of the study area. Another significant characteristic of PCA is the immediate recognition of the main patterns representing the overall variance of the original dataset. Moreover, the analyzed study cases demonstrate that this technique and the adopted grouping procedure discriminate especially well the large scale heterogeneities in contexts where significant geological changes occur

Comparing Techniques for Mobile Interaction with Objects from the Real World.

Mobile interaction with objects from the real world is gaining in popularity and importance as different mobile technologies increasingly provide the basis for the extraction and usage of information from physical objects. So far, Physical Mobile Interaction is used in rather simple ways. This paper presents a comparison and evaluation of more complex and sophisticated techniques for Physical Mobile Interaction. The results indicate the importance of usability guidelines that pay attention to these new interaction techniques

Inversion of surface wave data for subsurface shear wave velocity profiles characterized by a thick buried low-velocity layer

The study formed part of the SIMIT project (Integrated Italy-Malta Cross-Border System of Civil Protection) (B1-2.19/11) part-financed by the European Union under the ItaliaMalta Cross-Border Cooperation Programme, 2007–2013.The islands composing the Maltese archipelago (Central Mediterranean) are characterized by a four-layer sequence of limestones and clays. A common feature found in the western half of the archipelago is Upper Coralline Limestone (UCL) plateaus and hillcaps covering a soft Blue Clay (BC) layer which can be up to 75 m thick. The BC layer introduces a velocity inversion in the stratigraphy, implying that the VS30 (traveltime average sear wave velocity (VS) in the upper 30 m) parameter is not always suitable for seismic microzonation purposes. Such a layer may produce amplification effects, however might not be included in the VS30 calculations. In this investigation, VS profiles at seven sites characterized by such a lithological sequence are obtained by a joint inversion of the single-station Horizontal-to-Vertical Spectral Ratios (H/V or HVSR) and effective dispersion curves from array measurements analysed using the Extended Spatial Auto-Correlation technique. The lithological sequence gives rise to a ubiquitous H/V peak between 1 and 2 Hz. All the effective dispersion curves obtained exhibit a ‘normal’ dispersive trend at low frequencies, followed by an inverse dispersive trend at higher frequencies. This shape is tentatively explained in terms of the presence of higher mode Rayleigh waves, which are commonly present in such scenarios. Comparisons made with the results obtained at the only site in Malta where the BC is missing below the UCL suggest that the characteristics observed at the other seven sites are due to the presence of the soft layer. The final profiles reveal a variation in the VS of the clay layer with respect to the depth of burial and some regional variations in the UCL layer. This study presents a step towards a holistic seismic risk assessment that includes the implications on the site effects induced by the buried clay layer. Such assessments have not yet been done for Malta.peer-reviewe

Inversion of surface wave data for shear-wave velocity profiles : case studies of a thick buried low-velocity layer in Malta

The islands composing the Maltese archipelago (Central Mediterranean) are characterised by a four layer sequence of limestones and clays, with the Lower Coralline Limestone being the oldest exposed layer. The hard Globigerina Limestone (GL) overlies this layer and is found outcropping in the eastern part of Malta and western part of Gozo. The rest of the islands are characterised by Upper Coralline Limestone (UCL) plateaus and hillcaps covering a soft Blue Clay (BC) layer which can be up to 75 m thick. Thus the BC layer introduces a velocity inversion in the stratigraphy, and makes the Vs30 parameter not always suitable for seismic microzonation purposes. Such a layer may still produce amplification effects, however would not contribute to the numerical mean of Vs in the upper 30m. Moreover, buildings are being increasingly constructed on this type of geological foundation. Obtaining the shear wave (Vs) profiles of the different layers around the islands is the first step needed for a detailed study of local seismic site response. A survey of Vs in each type of lithology and around the islands has never been undertaken.N/

Irescenari. Le ICT nel futuro del sistema socioeconomico piemontese. Nuovi paradigmi, opportunità di sviluppo e divari digitali

Terzo Rapporto triennale sugli scenari evolutivi del Piemonte. Coordinamento scientifico Paolo Buran ; 2008/9- Indice #5- Introduzione #7- Le ICT e la costruzione della società dell'informazione #8- Il paradigma Web2.0: una rete partecipata, relazionale e integrata #13- Alcuni tratti delle dinamiche della società dell'informazione in Piemonte #18- Opportunità e sfide future per il sistema socio-economico regionale #26- Riferimenti bibliografici #3

GPU peer-to-peer techniques applied to a cluster interconnect

Modern GPUs support special protocols to exchange data directly across the PCI Express bus. While these protocols could be used to reduce GPU data transmission times, basically by avoiding staging to host memory, they require specific hardware features which are not available on current generation network adapters. In this paper we describe the architectural modifications required to implement peer-to-peer access to NVIDIA Fermi- and Kepler-class GPUs on an FPGA-based cluster interconnect. Besides, the current software implementation, which integrates this feature by minimally extending the RDMA programming model, is discussed, as well as some issues raised while employing it in a higher level API like MPI. Finally, the current limits of the technique are studied by analyzing the performance improvements on low-level benchmarks and on two GPU-accelerated applications, showing when and how they seem to benefit from the GPU peer-to-peer method.Comment: paper accepted to CASS 201

Evaluation of seismic site response in the Maltese archipelago

The investigation of local ground conditions is an important part of seismic hazard assessment (Fäh et al., 2003). It is now well–established that earthquake ground shaking is not only a function of the earth- quake magnitude and epicentral distance, but also of the site conditions, including soft layers in the sub–soil stratification and topographical features. Local geology can greatly alter the seismic waves from earthquakes by amplifying their amplitude, changing the frequency content and increasing the shaking duration during an earthquake (Kramer, 1996). In fact, several unconsolidated soft sites have suffered significantly greater damage than rock sites. One case was the 1985 Michoacán earthquake which showed low peak ground acceleration near the epicenter, yet caused severe damage in Mexico City, which is found more than 350 km away and is characterized by soft shallow sediments (Campillo et al., 1989).peer-reviewe

Development and validation of serum bilirubin nomogram to predict the absence of risk for severe hyperbilirubinaemia before discharge: a prospective, multicenter study

Early discharge of healthy late preterm and full term newborn infants has become common practice because of the current social and economic necessities. Severe jaundice, and even kernicterus, has developed in some term infants discharged early. This study was designed to elaborate a percentile-based hour specific total serum bilirubin (TSB) nomogram and to assess its ability to predict the absence of risk for subsequent non physiologic severe hyperbilirubinaemia before discharge