Design,test and analysis of a light‐weight dissipative bracing system for seismic protection of structures     

Emanuele Renzi  Salvatore Perno  Silvia Pantanella  Vincenzo Ciampi 《地震工程与结构动力学》2007,36(4):519-539

The paper deals with the proposal and the experimental validation of a novel dissipative bracing system for the seismic protection of structures; compared with other similar systems, it is characterized by smaller size and weight, which makes it easier to move and to install, as well as particularly suitable to be inserted in light‐framed structures (e.g. steel structures of industrial plants). The proposed system consists of an articulated quadrilateral with steel dissipaters inserted, to be connected by tendons to frame joints; the prototypes have been designed and realized for the seismic protection of a two‐storey, large‐scale, steel frame, specially designed for shaking‐table tests. The paper, after an illustration of the system, and of its design and behaviour, presents the shaking‐table tests carried out. The experimental results have fully validated the proposed system, showing its good performance in controlling the seismic response of framed structures. A numerical non‐linear model, set up and validated on the basis of the physical tests, has been used to help interpreting the experimental results, but also to perform parametrical studies for investigating the influence of the design parameters on the performance of the control system. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

The ground-based InSAR monitoring system at Stromboli volcano: linking changes in displacement rate and intensity of persistent volcanic activity   总被引：1，自引：1，他引：0  

Federico Di Traglia  Emanuele Intrieri  Teresa Nolesini  Federica Bardi  Chiara Del Ventisette  Federica Ferrigno  Sara Frangioni  William Frodella  Giovanni Gigli  Alessia Lotti  Carlo Tacconi Stefanelli  Luca Tanteri  Davide Leva  Nicola Casagli 《Bulletin of Volcanology》2014,76(2):1-18

Stromboli volcano (Aeolian Archipelago, Southern Italy) experienced an increase in its volcanic activity from late December 2012 to March 2013, when it produced several lava overflows, major Strombolian explosions, crater-wall collapses pyroclastic density currents and intense spatter activity. An analysis of the displacement of the NE portion of the summit crater terrace and the unstable NW flank of the volcano (Sciara del Fuoco depression) has been performed with a ground-based interferometric synthetic aperture radar (GBInSAR) by dividing the monitored part of the volcano into five sectors, three in the summit vents region and two in the Sciara del Fuoco. Changes in the displacement rate were observed in sectors 2 and 3. Field and thermal surveys revealed the presence of an alignment of fumaroles confirming the existence of an area of structural discontinuity between sectors 2 and 3. High displacement rates in sector 2 are interpreted to indicate the increase in the magmastatic pressure within the shallow plumbing systems, related to the rise of the magma level within the conduits, while increased displacement rates in sector 3 are connected to the lateral expansion of the shallow plumbing system. The increases and decreases in the displacement rate registered by the GBInSAR system in the upper part of the volcano have been used as a proxy for changes in the pressure conditions in the shallow plumbing system of Stromboli volcano and hence to forecast the occurrence of phases of higher-intensity volcanic activity.  相似文献   

Monitoring crater-wall collapse at active volcanoes: a study of the 12 January 2013 event at Stromboli     

Sonia Calvari  Emanuele Intrieri  Federico Di Traglia  Alessandro Bonaccorso  Nicola Casagli  Antonio Cristaldi 《Bulletin of Volcanology》2016,78(5):39

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Tracking dynamics of magma migration in open-conduit systems     

Sébastien Valade  Giorgio Lacanna  Diego Coppola  Marco Laiolo  Marco Pistolesi  Dario Delle Donne  Riccardo Genco  Emanuele Marchetti  Giacomo Ulivieri  Carmine Allocca  Corrado Cigolini  Takeshi Nishimura  Pasquale Poggi  Maurizio Ripepe 《Bulletin of Volcanology》2016,78(11):78

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From cylindrical to non‐cylindrical foreland basin: Pliocene–Pleistocene evolution of the Po Plain–Northern Adriatic basin (Italy)     

Chiara Amadori  Giovanni Toscani  Andrea Di Giulio  Francesco Emanuele Maesano  Chiara D&#x;Ambrogi  Manlio Ghielmi  Roberto Fantoni 《Basin Research》2019,31(5):991-1015

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Predicting new snow density in the Italian Alps: A variability analysis based on 10 years of measurements          下载免费PDF全文

Mauro Valt  Nicolas Guyennon  Franco Salerno  Anna B. Petrangeli  Rosamaria Salvatori  Paola Cianfarra  Emanuele Romano 《水文研究》2018,32(20):3174-3187

Despite its strong impact on the time evolution of the snowpack, current estimation of new snow density (ρ_hn) is usually accomplished either by using local empirical techniques or by assuming a constant snow density. Faced with the lack of an estimation model of ρ_hn valid for a wide spatial scale and supported by a suitable number of observations, this study aims to develop simple monthly linear regression models at scale of the entire Italian Alpine chain based on 12,112 snowfall observations at 122 stations, using only air temperature as predictor. Moreover, the remaining variance is investigated in both time and space, also considering some qualitative features of the snowfall events. The daily ρ_hn measurements present a mean value of 115 kg m^?3 (105 and 159 kg m^?3 for dry and wet conditions, respectively). The mean air temperature of the 24 hr preceding the snowfall event has been found to be the best predictor of the ρ_hn, within 31% of uncertainty. The analysis of associated residues allows supporting the idea that the adoption of a more local approach than the one analysed here is not able to substantially increase the predictive capabilities of the model. In fact, the main factor explaining the remaining variance over the air temperature is the wind, but in a complex orography, as mountain regions are, supplying realistic local wind fields is particularly challenging. Therefore, we conclude that using only the daily mean temperature as predictor is a good choice for estimating daily new snow density at scale of Italian Alpine chain, as well as at more regional scale.  相似文献   

Performance evaluation of automated approaches to building detection in multi-source aerial data     

Kourosh Khoshelham  Carla Nardinocchi  Emanuele Frontoni  Adriano Mancini  Primo Zingaretti 《ISPRS Journal of Photogrammetry and Remote Sensing》2010,65(1):123-133

Automated approaches to building detection in multi-source aerial data are important in many applications, including map updating, city modeling, urban growth analysis and monitoring of informal settlements. This paper presents a comparative analysis of different methods for automated building detection in aerial images and laser data at different spatial resolutions. Five methods are tested in two study areas using features extracted at both pixel level and object level, but with the strong prerequisite of using the same training set for all methods. The evaluation of the methods is based on error measures obtained by superimposing the results on a manually generated reference map of each area. The results in both study areas show a better performance of the Dempster-Shafer and the AdaBoost methods, although these two methods also yield a number of unclassified pixels. The method of thresholding a normalized DSM performs well in terms of the detection rate and reliability in the less vegetated Mannheim study area, but also yields a high rate of false positive errors. The Bayesian methods perform better in the Memmingen study area where buildings have more or less the same heights.  相似文献   

Quaternary drainage network reorganization in the Colombian Eastern Cordillera plateau     

Lucía Struth  Emanuele Giachetta  Sean D. Willett  Lewis A. Owen  Eliseo Tesón 《地球表面变化过程与地形》2020,45(8):1789-1804

Dramatic drainage reorganization from initial longitudinal to transversal domains has occurred in the Eastern Cordillera of Colombia. We perform a regional analysis of drainage basin geometry and transformed river profiles based on the integral form of the slope-area scaling, to investigate the dynamic state of drainage networks and to predict the degree of drainage reorganization in this region. We propose a new model of drainage rearrangement for the Eastern Cordillera, based on the analyses of knickpoint distribution, normalized river profiles, landforms characteristic of river capture, erosion rates and palaeodrainage data. We establish that the oldest longitudinal basin captured by the Magdalena River network was the Suárez Basin at ≈409 ka, inferring the timing of abandonment of a river terrace using in situ produced cosmogenic beryllium-10 (¹⁰Be) depth profiles and providing a first estimation of incision rate of 0.07 mm/yr. We integrate published geochronologic data and interpret the last capture of the Sabana de Bogotá, providing a minimum age of the basin opening to the Magdalena drainage at ≈38 ka. Our results suggest that the Magdalena basin Increased its drainage area by integrating the closed basins from the western flank of the Eastern Cordillera. Our study also suggests that the Magdalena basin is an aggressor compared to the basins located in the eastern flank of the orogen and provides a framework for examining drainage reorganization within the Eastern Cordillera and in similar orogenic settings. The results improve our understanding of headward integration of closed basins across orogenic plateaux. © 2020 John Wiley & Sons, Ltd.  相似文献   

Approximate matching of analytic and numerical solutions for rapidly rotating neutron stars     

Emanuele Berti †  Nikolaos Stergioulas 《Monthly notices of the Royal Astronomical Society》2004,350(4):1416-1430

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Asymptotic stability of synchronous orbits for a gravitating viscoelastic sphere     

Dario Bambusi  Emanuele Haus 《Celestial Mechanics and Dynamical Astronomy》2012,114(3):255-277

We study the dynamics of a viscoelastic body whose shape and position evolve due to the gravitational forces exerted by a pointlike planet. We work in the quadrupole approximation. We consider the solution in which the center of mass of the body moves on a circular orbit, and the body rotates in a synchronous way about its axis, so that it always shows the same face to the planet as the Moon does with the Earth. We prove that if any internal deformation of the body dissipates some energy, then such an orbit is locally asymptotically stable. The proof is based on the construction of a suitable system of coordinates and on the use of LaSalle??s principle. A large part of the paper is devoted to the analysis of the kinematics of an elastic body interacting with a gravitational field. We think this could have some interest in itself.  相似文献