Landslide susceptibility assessment in the Peloritani Mts. (Sicily, Italy) and clues for tectonic control of relief processes

Abstract. Many destructive shallow landslides hit villages in the Peloritani Mountains area (Sicily, Italy) on 1 October 2009 after heavy rainfall. The collection of several types of spatial data, together with a landslide inventory, allows the assessment of the landslide susceptibility by applying a statistical technique. The susceptibility model was validated by performing an analysis in a test area using independent landslide information, the results being able to correctly predict more than 70% of the landslides. Furthermore, the susceptibility analysis allowed the identification of which combinations of classes, within the different factors, have greater relevance in slope instability, and afterwards associating the most unstable combinations (with a short–medium term incidence) with the endogenic processes acting in the area (huge regional uplift, fault activity). Geological and tectonic history are believed to be key to interpreting morphological processes and landscape evolution. Recent tectonic activity was found to be a very important controlling factor in landscape evolution. A geomorphological model of cyclical relief evolution is proposed in which endogenic processes are directly linked to superficial processes. The results are relevant both to risk reduction and the understanding of active geological dynamics

A Geometric Processing Workflow for Transforming Reality-Based 3D Models in Volumetric Meshes Suitable for FEA

Conservation of Cultural Heritage is a key issue and structural changes and damages can influence the mechanical behaviour of artefacts and buildings. The use of Finite Elements Methods (FEM) for mechanical analysis is largely used in modelling stress behaviour. The typical workflow involves the use of CAD 3D models made by Non-Uniform Rational B-splines (NURBS) surfaces, representing the ideal shape of the object to be simulated. Nowadays, 3D documentation of CH has been widely developed through reality-based approaches, but the models are not suitable for a direct use in FEA: the mesh has in fact to be converted to volumetric, and the density has to be reduced since the computational complexity of a FEA grows exponentially with the number of nodes

3D DIGITIZATION OF MUSEUM CONTENT WITHIN THE 3DICONS PROJECT

The main purpose of the European Project "3DIcons" is to digitize masterpieces of Cultural Heritage and provide the related 3D models and metadata to Europeana, an Internet portal that acts as an interface to millions of books, paintings, films, museum objects and archival records that have been digitised throughout Europe. The purpose of this paper is to define a complete pipeline which covers all technical and logistic aspects for creating 3D models in a Museum environment with no established digitization laboratory, from the 3D data acquisition to the creation of models that has to be searchable on the Internet through Europeana. The research group of Politecnico di Milano is dealing with the 3D modelling of the Archaeological Museum of Milan and most of its valuable content. In this paper an optimized 3D modelling pipeline is shown, that takes into account all the potential problems occurring during the survey and the related data processing. Most of the 3D digitization activity have been made exploiting the Structure From Motion (SfM) technique, handling all the acquisition (e.g. objects enlightenment, camera-object relative positioning, object shape and material, etc.) and processing problems (e.g. difficulties in the alignment step, model scaling, mesh optimization, etc.), but without neglecting the metric rigor of the results. This optimized process has been applied on a significant number of items, showing how this technique can allow large scale 3D digitization projects with relatively limited efforts

The representations of teachers’ role identity. A study on the “professional common sense”

The innovations introduced within a social and organizational context -the school context, in the case study discussed here- challenge the established systems of practices as well as people’s shared representations of their role and professional identity (Jensen & Wagoner, 2009; Castro & Batel, 2008). The innovations may even encourage the production of conflicting meanings (Elcheroth, Doise, & Reicher, 2011) able to facilitate or, on the other hand, hinder the expected transformations. Therefore, the study of the shared symbolic meanings may contribute to the acknowledgement of the dynamics of development of a system in terms of resistance or adhesion to change… which is a mandatory issue for the school system

Segmentation of 3D Models for Cultural Heritage Structural Analysis – Some Critical Issues

Cultural Heritage documentation and preservation has become a fundamental concern in this historical period. 3D modelling offers a perfect aid to record ancient buildings and artefacts and can be used as a valid starting point for restoration, conservation and structural analysis, which can be performed by using Finite Element Methods (FEA). The models derived from reality-based techniques, made up of the exterior surfaces of the objects captured at high resolution, are - for this reason - made of millions of polygons. Such meshes are not directly usable in structural analysis packages and need to be properly pre-processed in order to be transformed in volumetric meshes suitable for FEA. In addition, dealing with ancient objects, a proper segmentation of 3D volumetric models is needed to analyse the behaviour of the structure with the most suitable level of detail for the different sections of the structure under analysis. Segmentation of 3D models is still an open issue, especially when dealing with ancient, complicated and geometrically complex objects that imply the presence of anomalies and gaps, due to environmental agents such as earthquakes, pollution, wind and rain, or human factors. The aims of this paper is to critically analyse some of the different methodologies and algorithms available to segment a 3D point cloud or a mesh, identifying difficulties and problems by showing examples on different structures

Flight flexibility in strategic traffic planning: visualisation and mitigation use case

The concept of strategic traffic planning that takes into account changing airspace configurations, their capacity, and allows the quantification of flight flexibility is presented in this paper: the visualization of the results and an example of possible use. The concept is implemented through two deterministic optimization models. Here, we focus on the output of the models, which identifies the departure times, trajectories, flight flexibility and the list of saturated sector-hours throughout the day, based on the configurations used during the day. In order to make the output understandable to various stakeholders, we use a visualization tool and a set of performance indicators. The information on the saturated sectors, and their impact on flexibility (criticality index) is taken as an input in the example of mitigation action application by Air Navigation Service Providers, aimed at improving the situation. A mitigation strategy of increasing capacity of saturated airspace is implemented, and results show that the improvements in flexibility can be achieved