On the Statistical Properties of Turbulent Energy Transfer Rate in the Inner Heliosphere     

Luca Sorriso-Valvo  Francesco Carbone  Silvia Perri  Antonella Greco  Raffaele Marino  Roberto Bruno 《Solar physics》2018,293(1):10

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Pile‐head kinematic bending in layered soil     

Raffaele Di Laora  George Mylonakis  Alessandro Mandolini 《地震工程与结构动力学》2013,42(3):319-337

Kinematic effects at the head of a flexible vertical pile embedded in a two‐layer soil deposit are investigated by means of rigorous three‐dimensional elastodynamic finite‐element analyses. Both pile and soil are idealized as linearly viscoelastic materials, modelled by solid elements, without the restrictions associated with the use of strength‐of‐materials approximations. The system is analyzed by a time‐Fourier approach in conjunction with a modal expansion in space. Constant viscous damping is considered for each natural mode, and an FFT algorithm is employed to switch from frequency to time domain and vice versa in natural or generalized coordinates. The scope of the paper is to: (a) elucidate the role of a number of key phenomena controlling the amplitude of kinematic bending moments at the pile head; (b) propose a simplified semi‐analytical formula for evaluating such moments; and (c) provide some remarks about the role of kinematic bending in the seismic design of pile foundations. The results of the study provide a new interpretation of the interplay between interface kinematic moments and corresponding head moments, as a function of layer thickness, pile‐to‐soil stiffness ratio, and stiffness contrast between the soil layers. In addition, the role of diameter in designing against kinematic action, with or without the presence of an inertial counterpart, is discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Atmospheric Background Measurement in the 300–400 nm Band with a Balloon Borne Experiment During a Nocturnal Flight     

Giovanni La Rosa  Gaetano Agnetta  Benedetto Biondo  Osvaldo Catalano  Filippo Celi  Renato Di Raffaele  Salvatore Giarrusso  Angelo Mangano  Francesco Russo  John Linsley  Angelo Lo Bue 《Astrophysics and Space Science》2001,276(1):219-226

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Accurate hypocentre locations in the Middle-Durance Fault Zone, South-Eastern France     

Sebastiano Imposa  Jean-Pierre Fourno  Rosario Raffaele  Antonio Scaltrito  Luciano Scarfi 《Central European Journal of Geosciences》2009,1(4):416-423

A one-dimensional velocity model and station corrections for the Middle-Durance fault zone (south-eastern France) were computed by inverting P-wave arrival times recorded on a local seismic network of 8 stations. A total of 93 local events with a minimum of 6 P-phases, RMS 0.4 s and a maximum gap of 220° were selected. Comparison with previous earthquake locations shows an improvement for the relocated earthquakes. Tests were carried out to verify the robustness of inversion results in order to corroborate the conclusions drawn from our findings. The obtained minimum 1-D velocity model can be used to improve routine earthquake locations and represents a further step toward more detailed seismotectonic studies in this area of south-eastern France.  相似文献   

Geochemistry and metamorphic evolution of the Pohorje Mountain eclogites from the easternmost Austroalpine basement of the Eastern Alps (Northern Slovenia)     

Raffaele Sassi  Claudio Mazzoli  Christine Miller 《Lithos》2004,78(3):235-261

Kyanite-rich and quartz-rich eclogites occur as lenses within amphibolite-facies quartzo-feldspathic gneisses in the Pohorje Mountains, Northern Slovenia, that form the easternmost Austroalpine basement. Major and trace elements indicate that the kyanite-rich eclogites were derived from plagioclase-rich gabbroic cumulates, whereas the quartz-rich eclogites represent more fractionated basaltic compositions. Both varieties are characterized by a LREE-depleted N-MORB type REE signature. Geothermobarometry and P-T pseudosections indicate that eclogites equilibrated at 1.8-2.5 GPa and 630-700 °C, consistently with the lack of coesite and with equilibration conditions of the chemically similar eclogites from the adjacent basement units at Koralpe and Saualpe type localities. Decompression reaction textures include (i) clinopyroxene-plagioclase intergrowths after omphacite, (ii) replacement of kyanite by corundum-plagioclase-spinel±sapphirine symplectites, (iii) breakdown of phengite to biotite-plagioclase sapphirine symplectites. The results of this study indicate that Koralpe, Saualpe and Pohorje high-pressure rocks represent former MORB-type oceanic crust that was subducted in the course of the late Cretaceous (approximately 100 Ma ago) collision between the European and the Apulian plates.  相似文献   

Experimental study of the seismic properties of the Eastern Alps (Italy) along the Aurina–Tures–Badia Valleys transect     

Claudio Mazzoli  Raffaele Sassi  Luigi Burlini 《Tectonophysics》2002,354(3-4)

In order to better constrain the interpretation and the nature of the seismic reflectors, experimental measurements at high confining pressure (up to 300 MPa) and room temperature of the compressional wave velocity (Vp) on 10 samples representative of the most common lithologies along the Aurina (Ahrntal), Tures (Tauferer Tal), and Badia (Abtei Tal) Valleys profile (Eastern Alps, Italy) have been performed. For each sample, the speed of ultrasonic waves was measured in three mutually perpendicular directions, parallel and normal to the rock foliation and lineation.The main results are:(a) Good agreement between the calculated vs. measured modal compositions of the considered rocks, indicating that they were presumably equilibrated at the estimated P–T conditions; therefore, the seismic properties are representative of the crustal level indicated by the thermobarometry.(b) Measured and calculated average Vp are in good agreement, and are typical of mid-crustal level (6.0–6.5 km/s). Only the amphibolites show Vp typical of the lower crust (7.2 km/s).(c) The seismic anisotropy of metapelites is very high (12–27%), both with orthorhombic and transverse isotropy symmetry; amphibolites are transversely isotropic with an anisotropy of 8%; orthogneisses and granitoids are isotropic or weakly anisotropic.(d) The contacts between amphibolites and all other rock types may generate good reflections, provided they are not steeply inclined. Although the metamorphic foliation remains steeply inclined, discordant buried sub-horizontal igneous contacts may be detected.  相似文献   

The Loci of Satellite Positions: A Constellation Design Approach     

Giancarlo Lucarelli  Raffaele Picone  Salvatore Troisi 《Celestial Mechanics and Dynamical Astronomy》1998,70(1):59-73

In special cases in which satellite constellations can be described by a limited set of parameters, a correlation between the latter and the constellation characteristics (i.e. shape and kinematics of the satellite configurations) has been investigated. Such cases may be a useful starting point for designing more complex constellations in order to achieve better the desired performances. Therefore, this proves to be one way to fix an initial set of parameters once the desired behaviour of the constellation has been established on the basis of the operational purposes required. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

The Impact of Human Recreational Activities in Marine Protected Areas: What Lessons Should Be Learnt in the Mediterranean Sea?   总被引：2，自引：0，他引：2  

Marco Milazzo  Renato Chemello  Fabio Badalamenti  Raffaele Camarda  Silvano Riggio 《Marine Ecology》2002,23(S1):280-290

Abstract. The aesthetic appeal of marine reserves and the facilities provided, together with the increased public awareness of nature, all contribute to creating massive tourism in MPAs. Human activities are being changed inside MPAs in two ways: humans as top predators are generally being removed, but in turn they could come back at great numbers as visitors.
Many authors have studied the impact of visitors, and the results highlight that the consequences can be very substantial and may represent a severe threat to the overall diversity of marine communities. To date, the documented effects of human recreational activities on natural communities are restricted to assessing the consequences of trampling over intertidal and upper infralittoral areas, boat anchoring in seagrass meadows and tropical reefs, or SCUB A-diving.
In this paper we review the available literature world-wide on the effects of human recreational activities in marine communities. The objective is to address the extent of these impacts and to highlight the gaps of knowledge to be filled in order to optimise decision making on research, monitoring, and management of Mediterranean MPAs. A specific plan for managing tourism use in each Mediterranean MPA should be designated. These strategies should be implemented through education, training, and changes in legislation and policy.  相似文献   

A method for designing the longitudinal spacing of slope-stabilising shafts     

Raffaele Di Laora  Vincenzo Fioravante 《Acta Geotechnica》2018,13(5):1141-1153

The work at hand deals with the design of the longitudinal spacing among rows of closely spaced large-diameter shafts used to stabilise a precarious slope. The problem under consideration is idealised through a conceptual framework where an unstable mass of an infinitely long slope pushes a stable portion of soil adjacent to shafts, leading to failure along a slip surface passing through the upper end of the reinforcement elements. By exploiting the upper bound theorem of plastic collapse, a closed-form solution is derived for the load required for the failure of the stable mass as a function of geometrical and mechanical parameters of the slope and the soil. Results are validated through physical model tests by means of geotechnical centrifuge. Given the satisfactory agreement between analytical and experimental results, the model is extended to evaluate the safety conditions of the reinforced slope.  相似文献   

A maritime decision support system to assess risk in the presence of environmental uncertainties: the REP10 experiment     

Raffaele?GrassoEmail author  Marco?Cococcioni  Baptiste?Mourre  Jacopo?Chiggiato  Michel?Rixen 《Ocean Dynamics》2012,62(3):469-493

The aim of this work is to report on an activity carried out during the 2010 Recognized Environmental Picture experiment, held in the Ligurian Sea during summer 2010. The activity was the first at-sea test of the recently developed decision support system (DSS) for operation planning, which had previously been tested in an artificial experiment. The DSS assesses the impact of both environmental conditions (meteorological and oceanographic) and non-environmental conditions (such as traffic density maps) on people and assets involved in the operation and helps in deciding a course of action that allows safer operation. More precisely, the environmental variables (such as wind speed, current speed and significant wave height) taken as input by the DSS are the ones forecasted by a super-ensemble model, which fuses the forecasts provided by multiple forecasting centres. The uncertainties associated with the DSS’s inputs (generally due to disagreement between forecasts) are propagated through the DSS’s output by using the unscented transform. In this way, the system is not only able to provide a traffic light map (run/not run the operation), but also to specify the confidence level associated with each action. This feature was tested on a particular type of operation with underwater gliders: the glider surfacing for data transmission. It is also shown how the availability of a glider path prediction tool provides surfacing options along the predicted path. The applicability to different operations is demonstrated by applying the same system to support diver operations.  相似文献