76 research outputs found

    Monitoraggio delle deformazioni della cupola del Teatro Massimo di Palermo con l\u2019impiego di tecniche topografiche e fotogrammetriche integrate.

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    L\u2019articolo riporta i primi risultati di uno studio finalizzato al monitoraggio delle deformazioni della cupola del Teatro Massimo di Palermo provocate dalle dilatazioni termiche, con l\u2019impiego di tecniche topografiche e fotogrammetriche integrate. In particolare, sono state utilizzate due stazioni totali robotizzate e sistemi di fotogrammetria digitale di elevata precisione. Per correlare gli spostamenti dei carrelli sui quali poggia la struttura in acciaio della cupola con i gradienti termici, sono state acquisite immagini termiche diversificate. L\u2019obiettivo principale del lavoro consisteva nel confronto delle due tecniche di rilievo in relazione a misure di deformazione di entit\ue0 molto ridotta (submillimetrica). I risultati ottenuti dimostrano che i carrelli funzionano ancora correttamente. Infatti, per un gradiente termico di 6\ub0 C misurato dalla termo camera, entrambe le tecniche topografiche e fotogrammetriche hanno evidenziato spostamenti dell\u2019ordine di 0.8 mm, in accordo con le previsioni del modello teorico.This paper shows the first results of a study aimed at monitoring the deformations of the dome of the Massimo Theatre in Palermo caused by thermal dilatations, with the use of topographic and photogrammetric integrated techniques. Particularly, two robotic total stations and high precision digital photogrammetric systems were employed. In order to correlate the displacements of the rollers on which the steel structure of the dome rest with the thermal gradients, different thermal images were acquired. The main goal of the work was to compare the two techniques with reference to very small (sub-millimeter) deformation measurements. The obtained results show that the rollers are still working correctly. In fact, for a thermal gradient of 6 \ub0C surveyed by thermographic camera, both topographic and photogrammetric techniques determined displacements of the order of 0.8 mm, according with the expected deformations of the theoretic model

    Toward a comprehensive dam monitoring: On-site and remote-retrieved forcing factors and resulting displacements (gnss and ps–insar)

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    Many factors can influence the displacements of a dam, including water level variability and environmental temperatures, in addition to the dam composition. In this work, optical-based classification, thermal diachronic analysis, and a quasi-PS (Persistent Scatter) Interferometric SAR technique have been applied to determine both forcing factors and resulting displacements of the crest of the Castello dam (South Italy) over a one-year time period. The dataset includes Sentinel-1A images acquired in Interferometric Wide swath mode using the Terrain Observation with Progressive Scans SAR (TOPSAR); Landsat 8 Thermal Infrared Sensor (TIRS) thermal images, and Global Navigation Satellite System (GNSS) for interpreting the motion of the top of the dam retrieved via interferometry. Results suggest that it is possible to monitor both dam water level and temperature periodic forcing factors and resulting displacements via a synergistic use of different satellite images

    Toward a Comprehensive Dam Monitoring: On-Site and Remote-Retrieved Forcing Factors and Resulting Displacements (GNSS and PS–InSAR)

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    Many factors can influence the displacements of a dam, including water level variability and environmental temperatures, in addition to the dam composition. In this work, optical-based classification, thermal diachronic analysis, and a quasi-PS (Persistent Scatter) Interferometric SAR technique have been applied to determine both forcing factors and resulting displacements of the crest of the Castello dam (South Italy) over a one-year time period. The dataset includes Sentinel-1A images acquired in Interferometric Wide swath mode using the Terrain Observation with Progressive Scans SAR (TOPSAR); Landsat 8 Thermal Infrared Sensor (TIRS) thermal images, and Global Navigation Satellite System (GNSS) for interpreting the motion of the top of the dam retrieved via interferometry. Results suggest that it is possible to monitor both dam water level and temperature periodic forcing factors and resulting displacements via a synergistic use of different satellite images

    A Kalman filter single point positioning for maritime applications using a smartphone

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    Different positioning techniques have been largely adopted for maritime applications that require high accuracy kinematic positioning. The main objective of the paper is the performance assessment of a Single Point Positioning algorithm (SPP), with a Kalman filter (KF) estimator, adapted for maritime applications. The KF has been chosen as estimation technique due to the ability to consider both the state vector dynamic and the measurements. Particularly, in order to compute an accurate vertical component of the position, suitable for maritime applications, the KF settings have been modified by tuning the covariance matrix of the process noise. The algorithm is developed in Matlab environment and tested using multi-GNSS single-frequency raw data, collected by a smartphone located on board a moving ship. The algorithm performance evaluation is carried out in position domain and the results show an enhancement of meter order on vertical component compared to the classical SPP based on Least Square estimation technique. In addition, different GNSSs configurations are considered to verify the benefits of their integration in terms of accuracy, solution availability and geometry

    Autocracy-Sustaining Versus Democratic Federalism:Explaining the Divergent Trajectories of Territorial Politics in Russia and Western Europe

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    This article provides a comparative assessment of territorial politics in Russia and Western Europe. The consolidation or deepening of regional autonomy in Western Europe contrasts with the transformation of Russia from a segmented and highly centrifugal state into a centralized authoritarian state in the course of just two decades. The consolidation of territorial politics in Western Europe is linked to the presence of endogenous safeguards that are built into their territorial constitutional designs and most importantly to the dynamics that emanate from multi-level party competition in the context of a liberal and multi-level democracy. In contrast, in Russia, neither endogenous safeguards nor multi-level party democracy play an important role in explaining the dynamics of Russian federalism, but who controls key state resources instead. We argue that under Putin power dependencies between the Russian center and the regions are strongest where regional democracy is at its weakest, thus producing ‘autocracy-sustaining’ instead of a democratic federation. By studying the relationship between federalism and democracy in cases where both concepts are mutually reinforcing (as in Western Europe) with the critical case of Russia where they are not, we question the widely held view that democracy is a necessary pre-condition for federalism.Peer reviewe

    Big Domains Are Novel Ca2+-Binding Modules: Evidences from Big Domains of Leptospira Immunoglobulin-Like (Lig) Proteins

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    binds to a Big domains, which would provide a novel functional role of the proteins containing Big fold. with dissociation constants of 2–4 µM. Lig A9 and Lig A10 domains fold well with moderate thermal stability, have β-sheet conformation and form homodimers. Fluorescence spectra of Big domains show a specific doublet (at 317 and 330 nm), probably due to Trp interaction with a Phe residue. Equilibrium unfolding of selected Big domains is similar and follows a two-state model, suggesting the similarity in their fold. binding

    SARS-CoV-2 infection among hospitalised pregnant women and impact of different viral strains on COVID-19 severity in Italy: a national prospective population-based cohort study

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    OBJECTIVE: The primary aim of this article was to describe SARS-CoV-2 infection among pregnant women during the wild-type and Alpha-variant periods in Italy. The secondary aim was to compare the impact of the virus variants on the severity of maternal and perinatal outcomes. DESIGN: National population-based prospective cohort study. SETTING: A total of 315 Italian maternity hospitals. SAMPLE: A cohort of 3306 women with SARS-CoV-2 infection confirmed within 7 days of hospital admission. METHODS: Cases were prospectively reported by trained clinicians for each participating maternity unit. Data were described by univariate and multivariate analyses. MAIN OUTCOME MEASURES: COVID-19 pneumonia, ventilatory support, intensive care unit (ICU) admission, mode of delivery, preterm birth, stillbirth, and maternal and neonatal mortality. RESULTS: We found that 64.3% of the cohort was asymptomatic, 12.8% developed COVID-19 pneumonia and 3.3% required ventilatory support and/or ICU admission. Maternal age of 30-34 years (OR 1.43, 95% CI 1.09-1.87) and ≥35 years (OR 1.62, 95% CI 1.23-2.13), citizenship of countries with high migration pressure (OR 1.75, 95% CI 1.36-2.25), previous comorbidities (OR 1.49, 95% CI 1.13-1.98) and obesity (OR 1.72, 95% CI 1.29-2.27) were all associated with a higher occurrence of pneumonia. The preterm birth rate was 11.1%. In comparison with the pre-pandemic period, stillbirths and maternal and neonatal deaths remained stable. The need for ventilatory support and/or ICU admission among women with pneumonia increased during the Alpha-variant period compared with the wild-type period (OR 3.24, 95% CI 1.99-5.28). CONCLUSIONS: Our results are consistent with a low risk of severe COVID-19 disease among pregnant women and with rare adverse perinatal outcomes. During the Alpha-variant period there was a significant increase of severe COVID-19 illness. Further research is needed to describe the impact of different SARS-CoV-2 viral strains on maternal and perinatal outcomes

    Plant growth promoting rhizobia: challenges and opportunities

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    Democratic Deficit or the Europeanisation of Secession? Explaining the Devolution Referendums in Scotland

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    This article deals with the variation in the demand for self-government in Scotland – as measured by the vote in the two referendums – between 1979, when devolution was rejected, and 1997, when devolution was endorsed. The existing literature mainly deals with each of the two referendums in isolation and does not offer an explicitly comparative analysis of them. However, implicit comparisons contained in analyses of the 1997 referendum tend to identify as the main cause of the variation the 'democratic deficit' created by Conservative rule between 1979 and 1997, which was consistently rejected in Scotland. I take issue with this explanation on theoretical and empirical grounds and advances an alternative account grounded in an explicit comparison of the two referendums. Based on a rationalist approach, the analysis presented here identifies three key elements in the voting dynamics at the two points in time – a gap between support for self-government and the actual vote in the referendum; an interaction effect between attitudes to devolution and to independence; and the role of the European context in shaping perceptions of independence. I argue that significant change in these three variables (rather than a 'democratic deficit') appear to have been the most important determinants of the different results of the two referendums
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