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Abstract: Large scale three-dimensional numerical simulations of hypervelocity impact of Aluminum alloy 6061-T6 plates by Nylon 6/6 cylindrical projectile have been performed using the Optimal Transportation Meshfree (OTM) method of Li et al.[7] along with the seizing contact and variational material point failure algorithm [17,18]. The dynamic response of the Al6061-T6 plate including phase transition in the high strain rate, high pressure and high temperature regime expected in our numerical analysis is described by the use of a variational thermomechanical coupling constitutive model with SESAME equation of state, rate-dependent J2 plasticity with power law hardening and thermal softening and temperature dependent Newtonian viscosity. A polytropic type of equation of state fit to in-house ReaxFF calculations is employed to model the Nylon 6/6 projectile under extreme conditions. The evaluation of the performance of the numerical model takes the form of a conventional validation analysis. In support of the analysis, we have conducted experiments over a range of plate thicknesses of [0.5, 3.0] mm, a range of impact velocities of [5.0, 7.0]km/s and a range of obliquities of [0,70]o at Caltech's Small Particle Hypervelocity Range (SPHIR) Facility. Large scale three-dimensional OTM simulations of hypervelocity impact are performed on departmental class systems using a dynamic load balancing MPI/PThreads parallel implementation of the OTM method. We find excellent full field agreement between measured and computed perforation areas, debris cloud and temperature field. [Copyright &y& Elsevier]

Abstract: Geomorphological analysis is an essential element of many landslide monitoring and hazard assessment studies. Remote sensing techniques have long been an effective tool for such analyses. This paper presents results regarding a geomorphological investigation performed exploiting information derived from high resolution hyper-spectral airborne sensor MIVIS (Multi-spectral Infrared and Visible Imaging Spectrometer) images. The authors propose a workflow based on neural network algorithms used both for image geometric correction and classification. The case study area is the Middle Susa Valley (Italian Western-Alps). It includes the Cassas landslide, a well-known complex landslide affecting slopes on the southern side of the valley, near the town of Salbertrand. At this location several “lifelines” (railway, main roads, hydroelectric tunnels, etc.) are concentrated, and they suffer from a constant threat of landslide activity. Traditional geomorphological characterization of the landslide slope was improved by comparing field campaigns with further information extracted from remote-sensed datasets. Presented results include the identification and characterization of major elements of the present-day active unstable slope (debris-covered areas, fractured/disjointed rock walls, landslide accumulation borders), as well as of individual structural features and landforms (major faults and fractures, trenches, elongated depressions, counterslope scarps), related to long-term deep-seated gravitational slope deformation. [Copyright &y& Elsevier]

Abstract: Glaciers are among the best terrestrial indicators of climate change and thus glacier inventories have attracted a growing, worldwide interest in recent years. In Italy, the first official glacier inventory was completed in 1925 and 774 glacial bodies were identified. As the amount of data continues to increase, and new techniques become available, there is a growing demand for computer tools that can efficiently manage the collected data. The Research Institute for Geo-hydrological Protection of the National Research Council, in cooperation with the Departments of Computer Science and Earth Sciences of the University of Turin, created a database that provides a modern tool for storing, processing and sharing glaciological data. The database was developed according to the need of storing heterogeneous information, which can be retrieved through a set of web search queries. The database''s architecture is server-side, and was designed by means of an open source software. The website interface, simple and intuitive, was intended to meet the needs of a distributed public: through this interface, any type of glaciological data can be managed, specific queries can be performed, and the results can be exported in a standard format. The use of a relational database to store and organize a large variety of information about Italian glaciers collected over the last hundred years constitutes a significant step forward in ensuring the safety and accessibility of such data. Moreover, the same benefits also apply to the enhanced operability for handling information in the future, including new and emerging types of data formats, such as geographic and multimedia files. Future developments include the integration of cartographic data, such as base maps, satellite images and vector data. The relational database described in this paper will be the heart of a new geographic system that will merge data, data attributes and maps, leading to a complete description of Italian glacial environments. [Copyright &y& Elsevier]