1,721,003 research outputs found
Runout modelling of gravity-induced pyroclastic density currents at Stromboli volcano (Italy)
No full textGravity-induced pyroclastic density currents (PDCs) at Stromboli volcano were investigated by means numerical and empirical modelling. With the aim of testing the suitability of landslide numerical model DAN- 3D and empirical models are used related to gravity-induced PDCs, in particular this work presents the results of the back analysis of three events occurred on 1906, 1930 and 1944 at Stromboli volcano. These two methods were able to reproduce the extension and the order of magnitude of the thickness of the PDCs reported in the literature. The best results of DAN-3D models were obtained using a Voellmy model with frictional coefficient of f = 0.19 and a turbulence parameter ξ = 1000 m/s. The mobility terms, find with the numerical model, are compared with empirical data of literature of the similar events
Emergency management of the 2010 Mt. Rotolon landslide by means of a local scale GB-InSAR monitoring system
Full text linkAbstract. Diffuse and severe slope instabilities affected the whole Veneto region (Northeast Italy) between October 31st and November 2nd 2010, following a period of heavy and persistent rainfall. In this context on November 4th 2010 a large detrital mass detached from the cover of the Mt. Rotolon Deep Seated Gravitational Slope Deformation (DSGSD), located in the upper Agno River Valley, channelizing within the Rotolon Creek riverbed and evolving into a highly mobile debris flow. The latter phenomena damaged many hydraulic works, also putting at high risk bridges, local roads, together with population of the Maltaure, Turcati and Parlati villages located along the creek banks and of the Recoaro Terme town. Starting from the beginning of the emergency phase, the Civil Protection system was activated, involving the National Civil Protection Department, Veneto Region, and local administrations personnel and technicians, as well as scientific institutions. On December 8th 2010 a local scale monitoring system, based on a Ground Based Interferometric Synthetic Aperture Radar (GB-InSAR), was implemented in order to evaluate the slope deformation pattern evolution in correspondence of the debris flow detachment sector, with the final aim of assessing the landslide residual risk and manage the emergency phase. This paper describes the outcomes of a two years GB-InSAR monitoring campaign (December 2010–December 2012), its application for monitoring, mapping, and emergency management activities, in order to provide a rapid and easy communication of the results to the involved technicians and civil protection personnel, for a better understanding of the landslide phenomena and decision making process in a critical landslide scenario.
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Debris flow hazard assessment by means of numerical simulations: implications for the Rotolon creek valley (Northern Italy)
No full textOn 4th November 2010, a debris flow detached from a large debris cover accumulated above the lowermost portion of the Rotolon landslide (Vicentine Pre-Alps, NE Italy) and channelized in the valley below within the Rotolon Creek riverbed. Such event evolved into a highly mobile and sudden debris flow, damaging some hydraulic works and putting at high risk four villages located along the creek banks. A monitoring campaign was carried out by means of a ground based radar interferometer (GB-InSAR) to evaluate any residual displacement risk in the affected area and in the undisturbed neighbouring materials. Moreover, starting from the current slope condition, a landslide runout numerical modelling was performed by means of DAN-3D code to assess the impacted areas, flow velocity, and deposit distribution of the simulated events. The rheological parameters necessary for an accurate modelling were obtained through the back analysis of the 2010 debris flow event. Back analysis was calibrated with all of the available terrain data coming from field surveys and ancillary documents, such as topographic, geomorphological and geological maps, with pre- and post-event LiDAR derived DTMs, and with orthophotos. Finally, to identify new possible future debris flow source areas as input data for the new modelling, all the obtained terrain data were reanalysed and integrated with the GB-InSAR displacement maps; consequently, new simulations were made to forecast future events. The results show that the integration of the selected modelling technique with ancillary data and radar displacement maps can be a very useful tool for managing problems related to debris flow events in the examined area
Governare l’emergenza progettando la cura, tra conservazione materiale e fruizione in sicurezza. Approcci predittivi per Palazzo Pitti a Firenze
No full textThe paper presents the first results of a multidisciplinary research aimed at supporting a paradigm shift in the management of decay processes affecting the stone façades of the Pitti Palace in Florence, passing from emergency interventions to continuous care. The research deals with the issue of quality in heritage preservation by focusing on the planning of mid-to-long term activities; it assumes a predictive approach and stresses the circularity of knowledge over the lifespan of conservation works. The goal is to develop preventive conservation and management strategies to ensure the material consistency of the heritage asset and the safe public fruition of its outdoor spaces threatened by detachments and falling stone fragments.
The study is part of an Institutional Agreement signed in January 2023 between the Uffizi Galleries in Florence and the Department of Construction, Civil Engineering and Architecture of the Università Politecnica delle Marche, and benefits from the long-standing collaboration with the Lab of Stone Materials and Applied Geology, Environment and Landscape (DST-LAM) of the University of Florence. The scientific activities are targeted at enabling an experimental knowledge-based tool for assessing the risk of detachment and setting priorities in conservation. The knowledge areas include the results of the DST-LAM diagnostic analysis, which also serve to validate the proposed methodology, as well as data from historical-critical research, especially impacts of previous restorations, and the state of conservation of stone façades. The correlation between these different levels of knowledge through data analysis techniques provides a first predictive model to manage the complexity of this heritage; the structuring and meta-dating of the knowledge ‘input’ and ‘output’ for an operational and shareable database are also among the results to be improved and tested
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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