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51.
In this paper we respond to the criticisms of “Phenomenology of the Lense-Thirring effect in the Solar System” by Iorio et al. about the general relativistic phenomena of gravitomagnetism and frame-dragging. The claims of the paper by Iorio et al. are not reproducible in any of our independent analyses.  相似文献   
52.
Polarimetry is an area of high energy astrophysics which is still relatively unexplored, even though it is recognized that this type of measurement could drastically increase our knowledge of the physics and geometry of high energy sources. For this reason, in the context of the design of a Gamma-Ray Imager based on new hard-X and soft gamma ray focusing optics for the next ESA Cosmic Vision call for proposals (Cosmic Vision 2015-2025), it is important that this capability should be implemented in the principal on-board instrumentation. For the particular case of wide band-pass Laue optics we propose a focal plane based on a thick pixelated CdTe detector operating with high efficiency between 60–600keV. The high segmentation of this type of detector (1–2mm pixel size) and the good energy resolution (a few keV FWHM at 500keV) will allow high sensitivity polarisation measurements (a few % for a 10mCrab source in 106s) to be performed. We have evaluated the modulation Q factors and minimum detectable polarisation through the use of Monte Carlo simulations (based on the GEANT 4 toolkit) for on and off-axis sources with power law emission spectra using the point spread function of a Laue lens in a feasible configuration.  相似文献   
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Weather radars in investigating physical characteristics of precipitation are becoming essential instruments in the field of short term meteorological investigation and forecasting. To analyze the radar signal impact in hydrological forecasting, precipitation input fields, generated through a statistical mathematical model, are supplied to a distributed hydrological model. Such a model would allow the control of the basin response to precipitation measurements obtained by a meteorological radar and, in the meanwhile, to evaluate the influence of distributed input. The distributed model describes the basin hydrological behavior, subdividing it into distinct geometrical cells and increasing the physical significance by reproducing the distributed hydrographic basins characteristics, such as infiltration capacity, runoff concentration time, network propagation speed, soil moisture influence. Each basin cell is characterized by its geological, pedological and morphological status, and may be considered a unitary hydrological system, linked to the others by geomorphological and hydraulic relationships. To evaluate the dynamics of the flood event a synthetic representation of the channel network is introduced, where each stream branch is modeled as a linear reservoir. Finally, the discharge in the outlet section is derived, taking into account the hydraulic characteristics of the upstream branches.  相似文献   
55.
Riassunto Viene descritto ed illustrato un nuovo procedimento di registrazione del moto ondoso marino, il quale consiste sostanzialmente nel trasformare l'escursione verticale che subisce la superficie del mare nella compressione o dilatazione di una massa d'aria sovrastante racchiusa in un tubo verticale munito superiormente di opportuna membrana sensibile. Un tale apparecchio, installato a Prà (Genova) dal-l'Istituto Geofisico dell'Università di Genova, funziona con successo da alcuni mesi. Segue un esame dei primi risultati ivi conseguiti, dal quale appare l'importanza del passaggio dei fronti freddi sul moto ondoso del mare.
Summary A new method for the recording of sea-wave motion is described and explained. It consists in having the vertical movement of the sea surface transformed into compression or expansion of a volume of air enclosed in a tube which is carrying on its upper part a sensitive membrane. This self-recording instrument, set up at Prà (Genoa) by the Istituto Geofisico dell'Università di Genova is functioning since several months already without giving rise to objections. Some first results obtained up now are also examided, from which it appears the importance of the passage of cold fronts.

Zusammenfassung Es wird ein neues Verfahren für die Registrierung der Meereswellenbewegung beschrieben und erläutert. Es besteht darin, dass der vertikale Gang der Meeresoberfläche umgewandelt wird in Kompression oder Expansion einer in einem Rohre befindlichen Luftmasse, welche am oberen Teil von einer empfindlichen Membran geschlossen ist. Dieser Gerät, vom Istituto Geofisico dell'Università di Genova in Prà (Genua) aufgestellt, arbeitet bereits seit einigen Monaten einwandfrei. Einige vorläufige Ergebnisse werden dann erläutert, wofür auf die Bedeutung des Durchganges von Kaltfronten hingewiesen wird.
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Geological, geophysical and geotechnical investigations, for the characterization of the strong-motion recording sites managed by the Italian Civil Protection, have been carried out in the framework of the project “Italian strong-motion database in the period 1972–2004”. The project aimed at creating an updated database of strong-motion data acquired in Italy by different institutions in the time span 1972–2004, and at improving the quality of disseminated data. This article illustrates the state of the recording site characterization before the beginning of the project, explains the criteria adopted to select the sites where geophysical/geotechnical investigation have been performed and describes the results of the promoted field surveys.  相似文献   
58.
Liquefaction of saturated sand deposits under seismic excitation is studied on the basis of a fatigue failure approach. The model includes a stochastic treatment of the input, of the soil response and of the cumulative pore pressure effects produced by cycling stresses in the soil. A method of establishing safety factors against liquefaction is also considered. Results obtained from analysis of a case history confirm the applicability of the model for engineering purposes.  相似文献   
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