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Air-fall pyroclastic deposits on steep slopes in Campania (Southern Italy) are periodically sub-jected to rainfall-induced landslides that may evolve into catastrophic flowslides. To protect built-up areas, Early Warning Systems (EWSs) were implemented. Existing EWSs are essentially based on pluviometric thresholds or models which are unable to accurately monitor the physical phenomena which are responsible for flow-slide generation in pyroclastic deposits. Over the last 20 years, landslides with no evolution in flow-slide occurred in this area and the alarms generated by existing EWSs in the cases of rainfall were false and very expensive, thus, lowering population trust in EWSs. To improve the existing EWSs, two complex mod-els for pyroclastic soils from Cervinara and Sarno slopes are proposed in the paper, capable of simulating physical phenomena (such as, the saturation increase due to rainwater infiltration, mechanical degradation and undrained instability), control instability phenomena (landslide) and evaluate the post-failure evolution.

In this work we show an experiment on building an Open Information Extraction system (OIE) for Italian language. We propose a system wholly reliant on linguistic structures and on a small set of verbal behavior patterns defined putting together theoretical linguistic knowledge and corpus-based statistical information. Starting from elementary one-verb sentences, the system identifies elementary tuples and then, all their permutations, preserving the overall well-formedness (grammaticality) and trying to preserve semantic coherence (acceptability). Although the work focuses only on the Italian language, it can be proficiently extended also to other languages, since it is essentially based only on linguistic resources and on a representative corpus for the language under consideration.

Sistemi Early Warning possono essere introdotti a protezione dei centri abitati colpiti da colate di fango indotte da precipitazioni meteoriche in pendii ricoperti da depositi di natura piroclastica. Tali sistemi possono contenere modelli della risposta dei pendii semplificati basati su soglie d’innesco pluviometriche o contenere modelli più o meno complessi di comportamento dei pendii in grado di seguire i fenomeni fisici alla base tanto dell’innesco (processi di infiltrazione) quanto della loro evoluzione post-rottura (evoluzione in colata di fango). Nell’articolo vengono presentati i risultati sperimentali ottenuti per due siti campione presenti in Campania (Cervinara e Sarno). Sulla base di indagini in sito e di laboratorio, di prove di infiltrazione su modelli fisici di pendio in piccola scala e di dati provenienti dai sistemi di monitoraggio, vengono definite le relazioni tra suzione e resistenza al taglio, le curve di ritenzione idrica e le funzioni di permeabilità. Tali elementi costituiscono “ingredienti essenziali” per la definizione di modelli idro-geotecnici che tengano conto della reale natura dei terreni piroclastici e degli effetti che le condizioni di parziale saturazione hanno sulla risposta dei pendii all’infiltrazione delle acque meteoriche. Tali ingredienti consentiranno l’adeguamento degli attuali sistemi Early Warning migliorandone la capacità previsionale con un evidente vantaggio in termini di contenimento del rischio di falsi o intempestivi allarmi; ciò a fronte di costi per lo più già sostenuti.

We report on the first laser emission of (Lux Gd(1-x))3 Ga5O12 doped with Tm3+ ions obtaining a slope efficiency of 20% and a maximum output power of 170 mW centered at 2013 nm. Evidences of a multiline emission are shown. Moreover a spectroscopic investigation on six samples of (Lux Gd(1-x))3 Ga5O12:Tm3+ having different Lu concentrations is presented. In particular the stark sublevels energy of 3H6 and 3F4 manifolds have been determined. Spectroscopic data have been utilized to calculate absorption and emission cross sections and gain curves.

Slope failures in partially saturated pyroclastic slopes are often induced by rainwater infiltration. Monitoring pore pressure in the subsoil makes it possible to identify the most critical period for slope stability and to determine whether current site conditions are critical for slope failure (according to a Civil Protection approach). This paper deals with the behaviour observed from 2002 to 2011 in two test sites in southern Italy. Using the data obtained, typical aspects of groundwater regime are de-scribed. The effect of single rainfall events is recognized only in the shallowest lay-ers, with a relatively small perturbation in the suction trend compared to the ampli-tude of seasonal fluctuations (that reach 80 kPa). Minimum suction values occur during winter in all layers. Therefore, we can conclude that the critical period for landslide triggering is between January and April

A large part of the mountains of Campania, in southern Italy, are interested by catastrophic flowslides triggered by heavy rainfalls. The slopes are covered by shallow deposits of loose pyroclastic soils in unsaturated conditions, which equilibrium is assured by the contribution of apparent cohesion due to soil suction. Hence, a key tool for the prediction of slope stability is the short-term forecasting of intense and persistent rainfall events and the subsequent analysis of the hydrological response of the shallow covers during such events. To this aim a numerical tool, is presented, consisting of a module for stochastic short-term rainfall prediction and 3D finite volumes model of infiltration and seepage through porous medium, provided with a geotechnical module for slope stability analysis. The presented predictor of rainfall evolution consists of an event based stochastic model, allowing formulating real time predictions of the future evolution of a storm, conditioned to the observed part of the storm. The 3D code (I-MOD3D) was calibrated through back-analysis of infiltration tests on slope model (Olivares et al. 2009) and of in situ suction measurements (Olivares and Damiano, 2007) collected in a instrumented site on a slope where recently a catastrophic flowslide occurred. The calibrated model has been applied to real time predictions of the slope response during some observed storms, showing the reliability of the results of the proposed model, which may represent a useful tool for decision making to implement early warning systems. Olivares L. and Damiano E. (2007). Post-failure mechanics of landslides: laboratory investigation of flowslides in pyroclastic soils. Journal of Geotechnical and Geoenvironmental Engineering ASCE, 133(1): 51-62 Olivares L., Damiano E, Greco R, Zeni L, Picarelli L, Minardo A, Guida A, Bernini R (2009). An Instrumented Flume to Investigate the Mechanics of Rainfall-Induced Landslides in Unsaturated Granular Soils. GEOTECHNICAL TESTING JOURNAL, vol. 32; p. 1-11, ISSN: 0149-6115.

During intense and persistent rainfall events, shallow landslides are frequently triggered in mountainous areas of Campania (Italy). The physical characteristics of the involved soils are such that landslides often evolve in form of debris flows, causing huge damages to buildings and infrastructures and, in some cases, casualties. The slopes are covered with pyroclastic deposits, in form of alternating layers of volcanic ashes and pumices, laying above a pervious fractured calcareous bedrock, in some cases covered by a layer of impervious weathered ashes. Slope inclination is often larger than internal friction angle of such ashes (around 38 ), thus equilibrium is assured by the contribution of apparent cohesion due to soil suction in unsaturated conditions. That is why, when soil approaches saturation and consequently suction decreases, slope failures often occur. Understanding the role played by the different layers and by the bottom boundary condition at the soil-bedrock interface is essential to develop reliable models of layered slope response to rainfall infiltration, allowing to define triggering conditions of landslides. To this aim, infiltration tests in small scale model slopes have been carried out in an instrumented flume. In the flume, a model slope is reconstituted by a moist-tamping technique and subjected to an artificial uniform rainfall. The state of stress and strain of the soil is monitored with various sensors during the entire test. In particular, soil suction is measured at different locations and depths with mini-tensiometers, and soil moisture is measured with TDR, here applied with an innovative technique allowing to estimate soil water content distribution along the entire thickness of the deposit. Infiltration and evaporation experiments in artificial slopes, with alternating layers of volcanic ashes and pumices, have been carried out with various inclinations and bottom boundary conditions. Coupling measured values of soil suction and water content have allowed to define water retention curves for volcanic ashes and pumices. The curves obtained for the ashes look quite different form retention curves obtained with standard laboratory techniques over either undisturbed or reconstituted soil specimens. The performed infiltration experiments have been simulated with a mathematical model based on the integration of Richards equation with the finite volumes technique. The use of the retention curves obtained from the slope infiltration experiments, rather than the curves estimated from small specimens, resulted in a substantial improvement of the agreement between simulation results and experimental data, confirming the reliability of the obtained curves and the importance of physical modelling for building up reliable mathematical models of infiltration in complex geometry.

High elevation environments proved to be particularly sensitive to climate changes, in relation to an increase in instability especially in areas where the cryosphere is present. The purpose of this work is to present the geomatic methodologies that have been applied to study dynamical areas, such as glacial and periglacial ones, in order to detect morphological changes that can be ascribed to climatic changes. The working group has been composed by members of the University of Torino (GeoSitLab laboratory) and of the CNR-IRPI Torino, in the framework of the Alcotra 2007-2013 project n.56 GlaRiskAlp (Glacial Risks in the Western Alps). Remote sensing techniques, necessary for large or remote areas, have been integrated, for the purposes of this study, by GNSS campaigns in the field, using a fixed GPS station, and a kinematical one. In order to identify landscape changes over the tens of years, it is particularly useful the digital aerial photogrammetry which exploits historical aerial photos that are orthorectified, to extract themes for a topographical and geomorphological characterization of landscape at regional scale. For the specific purposes of our work, the DEM extraction, at a local scale, from flights of different years, is useful to make comparisons of glacier surface. All data have been implemented in a GIS.

In questo lavoro si presenta un'analisi dell'applicabilità di alcune tecniche geomatiche per il monitoraggio di settori a marcata dinamicità geomorfologica. La finalità ultima è quella di riconoscere in modo tempestivo i segnali dell'insorgere di un'eventuale instabilità che possano evolvere in situazioni di rischio. Il contributo specifico del gruppo di lavoro, composto da Università di Torino (GeoSITLab) e CNR-IRPI Torino, è stato finalizzato all'integrazione di una gamma di tecniche geomatiche ad alcuni settori dell'ambiente glacializzato piemontese, nell'ambito del progetto interreg alcotra n.56 GlaRiskAlp (Rischi Glaciali nelle Alpi Occidentali). In questo articolo si intende approfondire una parte dei risultati relativi al progetto in riferimento allo studio volto alla verifica dell'impiego di le tecniche di fotogrammetria aerea digitale e di posizionamento satellitare (GNSS).

Climate changes are more and more attracting the attention of the scientific community because of their direct impacts on geomorphic systems and human activities. A number of studies are currently under way to investigate the evolution of high elevation environments, which proved to be particularly sensitive to climate changes and point to increased in instability in areas of cryosphere occurrence. The here presented research has been developed in the framework of the Alcotra project n.56 "GlaRiskAlp", by CNR-IRPI Torino in collaboration with the DST Torino - GeoSitLab laboratory and is aimed to the validation of an integrated geomatic approach for the evaluation of geomorphologic changes, and related hazards, in glacial and periglacial areas, in the contest of present climatic trends. The proposed approach is based on the coupling of remote sensing techniques and field surveys, in particular digital aerial photogrammetry and satellite imagery, terrestrial scanning LiDAR, and GNSS survey. High-resolution terrestrial LiDAR acquisition, processing and interpretation are used to map periglacial areas in the three dimensions. Laser-generated models offer a visualization tool that, through the comparison of DEMs of different years, allow to detect and to interpret even small geomorphologic changes in time. GNSS-networks are suitable tools for detecting changes over larger surfaces, or horizontal ones. Digital aerial photogrammetry and satellite images can be used to create ortophotos and DTMs of different years, allowing the reconstruction of main geomorphologic changes over the last 50 years. The proposed approach has been applied to case studies of the Piemonte region (Western Italian Alps).

The results of laboratory infiltration experiments on instrumented small scale model slopes are presented. Loose granular pyroclastic soils from the mountainous area north-eastern of Napoli have been examined. The experiments aimed to reproduce the simple case of a homogeneous indefinite slope, for a better understanding of the hydraulic processes leading to slope failure. With this respect, useful information was provided by the results of coupled measurements of soil suction and volumetric water content, respectively carried out by minitensiometers and Time Domain Reflectometry. The obtained results indeed showed how soil wetting during rainfall infiltration took place under matric suction values around 5kPa smaller than what could be predicted by equilibrium water retention curves estimated in laboratory. Since steep slopes equilibrium is often guaranteed by cohesion increment due to suction under unsaturated conditions, the obtained result indicates that effective early warning of fast landslides should rely on direct monitoring of soil suction and water content in the field.