646 research outputs found

    A website to explore the TINITALY/01 DEM

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    In 2007, a new digital elevation model (DEM) of the whole Italian territory, named TINITALY/01, was presented by Tarquini et al. [2007]. This DEM was the final result of the DIGITALIA project supported by the Italian Ministero dell’Ambiente e della Tutela del Territorio in the framework of a general agreement involving the Istituto Nazionale di Geofisica e Vulcanologia (INGV). The whole database of this DEM, in the form of a 10 m cell size grid, is available to the INGV research community at the web portal Kharita (http://kharita.rm.ingv.it/dmap/). Tarquini et al. [2007] mentioned in short a dedicated website (http://webgis.pi.ingv.it/), where authorized users were allowed to explore full resolution nadiral or perspective shaded relief images (in stereo or conventional format) obtained from the TINITALY/01 DEM. The navigation of this website is now opened to the public. The present technical report illustrates this website, describing its content and unfolding related technological aspects

    Review of Methodologies and Metrics for Assessing the Quality of Random Number Generators

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    Random number generators are a key element for various applications, such as computer simulation, statistical sampling, and cryptography. They are used to generate/derive cryptographic keys and non-repeating values, e.g., for symmetric or public key cyphers. The strength of a data protection system against cyber attacks corresponds to the strength of the weakest point in the security chain. Therefore, from a mathematical point of view, the security chain can be compromised even if the strongest algorithm is implemented. In fact, if the system requires keys or other random values and the generation process shows a certain vulnerability, the security of the system itself can be compromised. In this article, we present the most reliable tools and methodologies and the main standardisation efforts in the field of computer security to assess the quality of random number generators and ensure that they can be applied to computer security applications by offering adequate security strength. We offer a comprehensive guide that can be used as a quick and practical reference by developers of random number generators of any type to evaluate the random bit streams generated by implemented modules and determine whether or not they can be used in cybersecurity applications. Finally, we also present some use cases to which we applied the presented approach

    Multiview 3D reconstruction in geosciences

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    Multiview three-dimensional (3D) reconstruction is a technology that allows the creation of 3D models of a given scenario from a series of overlapping pictures taken using consumer-grade digital cameras. This type of 3D reconstruction is facilitated by freely available software, which does not require expert-level skills. This technology provides a 3D working environment, which integrates sample/field data visualization and measurement tools. In this study, we test the potential of this method for 3D reconstruction of decimeter-scale objects of geological interest. We generated 3D models of three different outcrops exposed in a marble quarry and two solids: a volcanic bomb and a stalagmite. Comparison of the models obtained in this study using the presented method with those obtained using a precise laser scanner shows that multiview 3D reconstruction yields models that present a root mean square error/average linear dimensions between 0.11 and 0.68%. Thus this technology turns out to be an extremely promising tool, which can be fruitfully applied in geosciences

    Surface fitting in geomorphology - examples for regular-shaped volcanic landforms

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    In nature, several types of landforms have simple shapes: as they evolve they tend to take on an ideal, simple geometric form such as a cone, an ellipsoid or a paraboloid. Volcanic landforms are possibly the best examples of this ?ideal? geometry, since they develop as regular surface features due to the point-like (circular) or fissure-like (linear) manifestation of volcanic activity. In this paper, we present a geomorphometric method of fitting the ?ideal? surface onto the real surface of regular-shaped volcanoes through a number of case studies (Mt. Mayon, Mt. Somma, Mt. Semeru, and Mt. Cameroon). Volcanoes with circular, as well as elliptical, symmetry are addressed. For the best surface fit, we use the minimization library MINUIT which is made freely available by the CERN (European Organization for Nuclear Research). This library enables us to handle all the available surface data (every point of the digital elevation model) in a one-step, half-automated way regardless of the size of the dataset, and to consider simultaneously all the relevant parameters of the selected problem, such as the position of the center of the edifice, apex height, and cone slope, thanks to the highly performing adopted procedure. Fitting the geometric surface, along with calculating the related error, demonstrates the twofold advantage of the method. Firstly, we can determine quantitatively to what extent a given volcanic landform is regular, i.e. how much it follows an expected regular shape. Deviations from the ideal shape due to degradation (e.g. sector collapse and normal erosion) can be used in erosion rate calculations. Secondly, if we have a degraded volcanic landform, whose geometry is not clear, this method of surface fitting reconstructs the original shape with the maximum precision. Obviously, in addition to volcanic landforms, this method is also capable of constraining the shapes of other regular surface features such as aeolian, glacial or periglacial landforms

    I finanziamenti europei alla ricerca in università e in enti pubblici di ricerca: aspetti organizzativi e informativi per il supporto al ciclo di vista del progetto

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    European Union funding poses organizational challenges as well as requires adequate information management tools. Research support services have been set up in 90% of Italian universities, in the so-called Research Offices and in public research bodies, often in the International Relation Offices. The paper summarizes some considerations coming from state-of-the-art and illustrates the results of a dedicated survey which has been carried out on a sample of universities and research bodies of Italy. Both organizational structures to promote and manage the projects and features of information systems to support the whole project life-cycle are taken into account

    SHINe: Simulator for satellite on-board high-speed networks featuring SpaceFibre and SpaceWire protocols

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    The continuous innovation of satellite payloads is leading to an increasing demand of data-rate for on-board satellite networks. In particular, modern optical detectors generate and need to transfer data at more than 1 Gbps, a speed that cannot be satisfied with standardized technologies such as SpaceWire. To fill this gap, the European Space Agency (ESA) is supporting the development of a new high-speed link standard, SpaceFibre. SpaceFibre provides a data-rate higher than 6.25 Gbps, together with the possibility to use multiple Virtual Channels running over the same physical link, each one configurable with flexible Quality of Service parameters. These features make a SpaceFibre network very appealing but also complex to set up in order to achieve the desired end-to-end requirements. To help this process, a Simulator for HIgh-speed Network (SHINe) based on the open-source toolkit OMNeT++ has been developed and is presented in this paper. It supports the simulation of SpaceFibre and SpaceWire protocols in order to help both the final steps of the standardization process and the system engineers in the setup and test of new networks. SHINe allows to precisely simulate common network metrics, such as latency and bandwidth usage, and it can be connected to real hardware in a Hardware-in-the-Loop configuration

    An application of parallel computing to the simulation of volcanic eruptions

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    A parallel code for the simulation of the transient 3D dispersal of volcanic particles produced by explosive eruptions is presented. The model transport equations, based on the multiphase flow theory, describe the atmospheric dynamics of the gas-particle mixture ejected through the volcanic crater. The numerics is based on a finite-volume discretization scheme and a pressure-based iterative non-linear solver suited to compressible multiphase flows. The code has been parallelized by adopting an ad hoc domain partitioning scheme that enforces the load balancing. An optimized communication layer has been built over the Message-Passing Interface. The code proved to be remarkably efficient on several high-performance platforms and makes it possible to simulate fully 3D eruptive scenarios on realistic volcano topography

    Release of a 10-m-resolution DEM for the Italian territory: Comparison with global-coverage DEMs and anaglyph-mode exploration via the web

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    The 10-m-resolution TINITALY/01 DEM (Tarquini et al., 2007) is compared with the two, coarser-resolution, global-coverage, spaceborne-based SRTM and ASTER DEMs and with a high-resolution, LIDAR-derived DEM. Afterwards, we presented a webGIS which allows to explore a 10-m-resolution anaglyph layer showing the landforms of the whole Italian territory in 3D. The webGIS (http://tinitaly.pi.ingv.it/) is open to the public, and can be used to carry out a preliminary analysis of landforms. The TINITALY/01 DEM is available for scientific purposes on the basis of a research agreement (see the above website or write to [email protected])
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