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Nowadays, Unmanned Aerial Vehicles (UAVs), as well as Unmanned Surface Vehicles (USVs) or also Unmanned Underwater Vehicles (UUVs), later on simply called drones, have reached a sufficient degree of maturity to allow their use for various purposes [...]

Results of recent monitoring activities on potentially unstable areas of the NW volcano flank of La Fossa cone (Vulcano Island, Italy) are shown here. They are obtained by integration of data by aerial photogrammetry, terrestrial laser scanning (TLS) and GPS taken in the 1996–2011 time span. A comparison between multi-temporal models built from remote sensing data (photogrammetry and TLS) highlights areas characterized by ~7–10 cm/y positive differences (i.e., elevation increase) in the upper crown of the slope. The GPS measurements confirm these results. Areas characterized by negative differences, related to both mass collapses or small surface lowering, also exist. The higher differences, positive and negative, are always observed in zones affected by higher fumarolic activity. In the 2010–2012 time span, ground motions in the northern part of the crater rim, immediately above the upper part of observed area, are also observed. The results show different trends for both vertical and horizontal displacements of points distributed along the rim, with a magnitude of some centimeters, thus revealing a complex kinematics. A slope stability analysis shows that the safety factors estimated from these data do not indicate evidence of possible imminent failures. Nevertheless, new time series are needed to detect possible changes with the time of the stability conditions, and the monitoring has to go on.

An empirical approach is proposed in order to evaluate the largest spot spacing allowing the appropriate resolution to recognize the required surface details in a terrestrial laser scanner (TLS) survey. The suitable combination of laser beam divergence and spot spacing for the effective scanning angular resolution has been studied by numerical simulation experiments with an artificial target taken from distances between 25 m and 100 m, and observations of real surfaces. The tests have been performed by using the Optech ILRIS-3D instrument. Results show that the discrimination of elements smaller than a third of the beam divergence (D) is not possible and that the ratio between the used spot-spacing (ss) and the element size (TS) is linearly related to the acquisition range. The zero and first order parameters of this linear trend are computed and used to solve for the maximum efficient ss at defined ranges for a defined TS. Despite the fact that the parameters are obtained for the Optech ILRIS-3D scanner case, and depend on its specific technical data and performances, the proposed method has general validity and it can be used to estimate the corresponding parameters for other instruments. The obtained results allow the optimization of a TLS survey in terms of acquisition time and surface details recognition.

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.

On May 20, 2012, a Ml 5.9 seismic event hit the Emilia Po Plain, triggering intense earthquake activity along a broad area of the Po Plain across the provinces of Modena, Ferrara, Rovigo and Mantova (Figure 1). Nine days later, on May 29, 2012, a Ml 5.8 event occurred roughly 10 km to the SW of the first main shock. These events caused widespread damage and resulted in 26 victims. The aftershock area extended over more than 50 km and was elongated in the WNW-ESE direction, and it included five major aftershocks with 5.1 ≤Ml ≤5.3, and more than 2000 minor events (Figure 1). In general, the seismic sequence was confined to the upper 10 km of the crust. Minor seismicity with depths ranging from 10 km to 30 km extended towards the southern sector of the epicentral area (ISIDe, http://iside.rm.ingv.it/). […]

L’intervento di restauro non può prescindere dalla comprensione storica e strutturale del monumento. Il primo aspetto si esaurisce in una accurato studio delle fonti storiche e nella lettura dei segni architettonici mentre il secondo aspetto approfondisce gli assetti di equilibrio che nei secoli sono stati assunti dalla costruzione in risposta a mutati stati di equilibrio. Entrambi gli aspetti sono sintetizzati dalle mappe di deviazione ottenute dall’elaborazione dei dati del rilievo laser scanner e opportune primitive rappresentanti i macro-elementi in cui viene suddivisa la struttura. In particolare, coniugando la lettura delle mappe di deformazione con tecniche di lettura tematica del monumento si è sviluppato un metodo efficace per individuare precocemente i meccanismi di danno da terremoto e per ricostruirne la storia del danno. Tale metodo è ancora più utile in condizioni di pericolo in quanto esso si basa su tecniche che non necessitano del contatto con l’edificio. La pieve di Cantalovo (Verona, Italia), colpita da sisma nel XII sec. , è stata studiata portandone alla luce la storia dei danni e gli attuali meccanismi di danno in atto. The restoration is based on the comprehension of the monument architectural history and of its structural behavior. The fi rst topic regards historical sources and architectural marks understanding while the second one focuses on changes in time of structural balance. The deviations maps, obtained from laser scanning data processing and representative macro-elements primitives, can summarize both. In particular it is possible to elaborate an effi cient method to detect and study the damage mechanism, also providing information and dating past restorations, based on contactless and independent TLS and data imaging measurements. The method is applied to obtain the deformation state of Cantalovo’s church (Verona, IT), struck by earthquake on XII, pointing out both historical and present day damage mechanisms.

Il GPS (Global Positioning System) è un noto sistema di posizionamento globale in grado di fornire le coordinate spaziali di unoperatore, se munito di antenna e ricevitore satellitari, in qualunque punto della terra esso si trovi, in qualunque condizionemeteo ed in qualsiasi ora del giorno. Oggi al GPS, che è di proprietà del Dipartimento della Difesa degli Stati Uniti d'America(US DoD), si affiancano il GLONASS (sistema analogo russo) e altri sistemi di posizionamento globale basati su tecniche interferometriche spaziali a partire da segnali a microonde, ad esempio i nascenti Galileo (europeo) e BeiDou (cinese). Per questo motivo si parla diffusamente di sistemi GNSS cioè Global Navigation Satellite System. Remote monitoring of deformations in the island of Santorini: an integrated procedure for GPS data analysis at the INGV in Bologna The GPS (Global Positioning System) is a well-known global positioning system capable of providing the spatial coordi-nates of an operator, if equipped with an antenna and a re-ceiver satellite, at any point on the earth , and in any weather conditions and at any time of the day. Today, the GPS, which is owned by the Department of Defense of the United States of America (U.S. DoD), is aided by the GLONASS (the Russian analogue system) and other global positioning systems based on interferometry from space microwave signals, for example, the nascent Galileo (European) and Beidou (China). For this reason we talk at today about GNSS Global Navigation Satel-lite System.

La disciplina del restauro costituisce un ponte di collegamento fra le materie di carattere umanistico e quelle di carattere tecnico che si integrano le une alle altre nell’obiettivo comune di perpetuare i valori storici e architettonici di cui il monumento è depositario. Uno studio completo non può che essere effettuato mediante l’applicazione e l’integrazione di una vasta gamma di tecniche di rilievo, distruttive e non, mirate all’analisi delle strutture, allo studio dei terreni di fondazione e del suolo, senza tralasciare la valutazione degli effetti ambientali. Coniugando la tecnica avanzata del rilievo eseguito con il laser scanner con le indagini tematiche che si sviluppano attraverso la lettura stratigrafi ca verticale si conseguono risultati importanti per comprendere la complessità storico-costruttiva del monumento e quindi utili per il progetto di conservazione.The Two Towers and Accursio Palace Restoration is an interdiscipline connecting both historical-humanistic and scientifi ambits that work in synergy and complete each other by having the same purpose: to perpetuate the historical and architectonic substance of which a monument is depositary. With the aim of working consciously both about the knowledge of the manufacture and to plan the conservation and a new use of monuments, inter-disciplinarity is a fundamental premise. Through the conjugation of laser scanner survey together with thematic investigation that develop by means of a vertical stratigraphic reading (analysis and comprehension) it is possible to understand the historical-constructive complexity of monuments. The Two Towers and Accursio Palace (Bologna, Italy) study cases are here presented.

I sistemi laser a scansione terrestre caratterizzati da una lunga portata, cioè capaci di rilevare su distanze fino a 3 km, sono oggi sempre più utilizzati nel monitoraggio del territorio e nel controllo del dissesto o, in generale, delle variazioni morfologiche. Laser scanning survey of landslides by means of long distance ILRIS LR Terrestrial laser scanning (TLS) is a remote sensing technique for high density acquisition of the physical surface of scanned, currently used in geologic surveys, engineering practice, cultural heritage, and mobile mapping. The very long range scanners, allow the acquisition from distances of the order of about 1 km with material characterized by medium/high reflecting properties. At present, the efforts in technological advancements are highly aimed at the extension of maximum range, at the reduction of acquisition time, and so on. The ILRIS LR laser scanner, provided by Optech, is used to survey a very dense populated landslide area in the Tuscany Apennines, in the frame of a scientific experiment planned by INGV to test its performances.