Inversion of Multiconfiguration Complex EMI Data with Minimum Gradient Support Regularization: A Case Study     

Deidda  Gian Piero  Díaz de Alba  Patricia  Rodriguez  Giuseppe  Vignoli  Giulio 《Mathematical Geosciences》2020,52(7):945-970

Mathematical Geosciences - Frequency-domain electromagnetic instruments allow the collection of data in different configurations, that is, varying the intercoil spacing, the frequency, and the...  相似文献   

GRS evidence and the possibility of paleooceans on Mars     

James M. Dohm  Victor R. Baker  William V. Boynton  Alberto G. Fairén  Justin C. Ferris  Michael Finch  Roberto Furfaro  Trent M. Hare  Daniel M. Janes  Jeffrey S. Kargel  Suniti Karunatillake  John Keller  Kris Kerry  Kyeong J. Kim  Goro Komatsu  William C. Mahaney  Dirk Schulze-Makuch  Lucia Marinangeli  Gian G. Ori  Javier Ruiz  Shawn J. Wheelock 《Planetary and Space Science》2009,57(5-6):664-684

The Gamma Ray Spectrometer (Mars Odyssey spacecraft) has revealed elemental distributions of potassium (K), thorium (Th), and iron (Fe) on Mars that require fractionation of K (and possibly Th and Fe) consistent with aqueous activity. This includes weathering, evolution of soils, and transport, sorting, and deposition, as well as with the location of first-order geomorphological demarcations identified as possible paleoocean boundaries. The element abundances occur in patterns consistent with weathering in situ and possible presence of relict or exhumed paleosols, deposition of weathered materials (salts and clastic minerals), and weathering/transport under neutral to acidic brines. The abundances are explained by hydrogeology consistent with the possibly overlapping alternatives of paleooceans and/or heterogeneous rock compositions from diverse provenances (e.g., differing igneous compositions).  相似文献   

“Galileo Galilei” (GG) a small satellite to test the equivalence principle of Galileo, Newton and Einstein     

Anna M. Nobili  Gian Luca Comandi  Suresh Doravari  Donato Bramanti  Rajeev Kumar  Francesco Maccarrone  Erseo Polacco  Slava G. Turyshev  Michael Shao  John Lipa  Hansjoerg Dittus  Claus Laemmerzhal  Achim Peters  Jurgen Mueller  C. S. Unnikrishnan  Ian W. Roxburgh  Alain Brillet  Christian Marchal  Jun Luo  Jozef van der Ha  Vadim Milyukov  Valerio Iafolla  David Lucchesi  Paolo Tortora  Paolo De Bernardis  Federico Palmonari  Sergio Focardi  Dino Zanello  Salvatore Monaco  Giovanni Mengali  Luciano Anselmo  Lorenzo Iorio  Zoran Knezevic 《Experimental Astronomy》2009,23(2):689-710

“Galileo Galilei” (GG) is a small satellite designed to fly in low Earth orbit with the goal of testing the Equivalence Principle—which is at the basis of the General Theory of Relativity—to 1 part in 10¹⁷. If successful, it would improve current laboratory results by 4 orders of magnitude. A confirmation would strongly constrain theories; proof of violation is believed to lead to a scientific revolution. The experiment design allows it to be carried out at ambient temperature inside a small 1-axis stabilized satellite (250 kg total mass). GG is under investigation at Phase A-2 level by ASI (Agenzia Spaziale Italiana) at Thales Alenia Space in Torino, while a laboratory prototype (known as GGG) is operational at INFN laboratories in Pisa, supported by INFN (Istituto Nazionale di fisica Nucleare) and ASI. A final study report will be published in 2009.  相似文献   

Color mechanisms in spinel: cobalt and iron interplay for the blue color     

Veronica D’Ippolito  Giovanni Battista Andreozzi  Ulf Hålenius  Henrik Skogby  Kathrin Hametner  Detlef Günther 《Physics and Chemistry of Minerals》2015,42(6):431-439

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How the aggressiveness of rainfalls in the Mediterranean lands is enhanced by climate change     

Nazzareno Diodato  Gianni Bellocchi  Nunzio Romano  Giovanni Battista Chirico 《Climatic change》2011,108(3):591-599

Rainfall and overland flow are fundamental processes for Earth’s ecosystems but can also be land disturbing forces, particularly when triggered by extreme hydro-meteorological events. Examples of these extremes are rainstorms and related phenomena due to rainfall aggressiveness. They produce high-impact land processes such as soil erosion and nutrient losses. Economic and social consequences of these processes can be quite severe. However, hydrological extremes and their environmental implications are still poorly understood, particularly if analyzed in the context of climate change. Here, we analyze a 300 year long times series of historical rainfall patterns across the Mediterranean in the last three centuries and we investigate changes in the erosive forcing as related to climate changes. Our results show that the erosive forcing increased towards the end of the Little Ice Age (~1850) over western and central Mediterranean and that has been increasing in the recent warming period at low Mediterranean latitudes, due to a higher frequency of intensive storms. Such increased concentrated precipitation may lead to an intensification of land degradation processes triggered by soil erosion and transport across a range of scales from hillslopes to small catchments.  相似文献   

Optimal filtering high-resolution seismic reflection data using a weighted-mode empirical mode decomposition operator   总被引：2，自引：0，他引：2  

Leonardo Macelloni  Bradley Matthew Battista  Camelia Cristina Knapp 《Journal of Applied Geophysics》2011,75(4):603-614

Gas-hydrate related processes in deep-water marine settings exist on spatial scales that challenge conventional seismic reflection profiling to successfully image them. The conventional approach to acoustic identification of buried hydrates is to use advanced, cost-prohibitive survey techniques and highly customized software to define subsurface structure wherein compositional changes may be modeled and/or interpreted. This study adopts a different approach derived from recent theoretical advancements in signal processing. The method consists in optimal filtering high resolution, single-channel seismic reflection data using the Empirical Mode Decomposition (EMD). The time series is decomposed in sub-components and the noisy portions are suppressed adopting the technique that we referred as Weighted Mode(s) EMD. The optimal filtering greatly improves the resolution and fidelity of the seismic data set.High Resolution single channel seismic profiles, acquired over a carbonate\hydrates site in the northern Gulf of Mexico, manipulated in such way, show a complex, shallow subsurface, and suggest potential evidence for buried gas hydrates.  相似文献   

Performance‐based metamodel for healthcare facilities     

Gian Paolo Cimellaro  Michel Bruneau 《地震工程与结构动力学》2011,40(11):1197-1217

This paper introduces an organizational model describing the response of the Hospital Emergency Department (ED). The metamodel is able to estimate the hospital capacity and the dynamic response in real time and to incorporate the influence of the damage of structural and non‐structural components on the organizational ones. The waiting time is the main parameter of response and it is used to evaluate the disaster resilience index of healthcare facilities. Its behaviour is described using a double exponential function and its parameters are calibrated based on simulated data. The metamodel covers a large range of hospital configurations and takes into account hospital resources, in terms of staff and infrastructures, operational efficiency and existence of an emergency plan, maximum capacity and behaviour both in saturated and over‐capacitated conditions. The sensitivity of the model to different arrival rates, hospital configurations, and capacities and the technical and organizational policies applied during and before the strike of the disaster has been investigated. This model becomes an important tool in the decision process either for the engineering profession or for the policy makers. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

Geomorphological study of the Fadalto landslide, Venetian Prealps, Italy     

Giovanni Battista Pellegrini  Nicola Surian 《Geomorphology》1996,15(3-4)

This research deals with the Fadalto landslide (Lapisina Valley, Venetian Prealps), which took place in the Lateglacial and has continued its activity until today. Our aim is to recognize how the landslide failed, the causes of such failure and the activity of this landslide. The study of this landslide is important not only to understand the geomorphological history of this alpine area, and why the Piave River modified its course in the Late Pleistocene, but also the links with human activities, and specifically with the road and rail network.The geomorphological study, carried out by the interpretation of aerial photos and by a detailed field survey, has been integrated with a geological survey, geophysical investigations and a morphometric analysis (DTM). The Fadalto landslide is considered to be a rockslide reactivated in various phases, with different dimensions and with different characters (slides, slumps and flows). The landslides have been provoked by natural causes, both external and internal; the fundamental external causes are the retreat of the Würmian glacier and tectonic activity; the internal factors that decrease the shear resistance are the bedding planes and joints of the bedrock, the attitude of the rocks dipping towards the valley bottom and, as regards more recent failures, the presence of glacial deposits underlying the landslide debris. Besides, in recent times, we must also consider human activity as a cause of slope instability.As to the activity, the Fadalto landslide is defined “dormant”. This means that in this area there is a geomorphological risk connected with the important road and rail network of the Lapisina Valley.  相似文献   

Long term spectral variability in the soft gamma-ray repeater SGR 1900+14     

Andrea Tiengo  Paolo Esposito  Sandro Mereghetti  Lara Sidoli  Diego Götz  Marco Feroci  Roberto Turolla  Silvia Zane  Gian Luca Israel  Luigi Stella  Peter Woods 《Astrophysics and Space Science》2007,308(1-4):33-37

We present a systematic analysis of all the BeppoSAX data of SGR1900+14. The observations spanning five years show that the source was brighter than usual on two occasions: ～20 days after the August 1998 giant flare and during the 10⁵?s long X-ray afterglow following the April 2001 intermediate flare. In the latter case, we explore the possibility of describing the observed short term spectral evolution only with a change of the temperature of the blackbody component. In the only BeppoSAX observation performed before the giant flare, the spectrum of the SGR1900+14 persistent emission was significantly harder and detected also above 10 keV with the PDS instrument. In the last BeppoSAX observation (April 2002) the flux was at least a factor 1.2 below the historical level, suggesting that the source was entering a quiescent period.  相似文献   

The Surface of Cometary Nulcei Related Minor Icy Bodies     

Javier Licandro  Juan C. Guerra  Humberto Campins  Mario Di Martino  Luisa M. Lara  Ricardo Gil–Hutton  Gian P. Tozzi 《Earth, Moon, and Planets》2002,90(1-4):495-496

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