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171.
Evolutionary polynomial regression to alert rainfall-triggered landslide reactivation 总被引:3,自引:0,他引:3
Angelo Doglioni Francesco Fiorillo Francesco M. Guadagno Vincenzo Simeone 《Landslides》2012,9(1):53-62
The derivation of an alert model for landslide risk management is a paramount problem for those sites which are affected by
complex landslides involving strategic infrastructures as well as towns. This is a quite common scenario all over the world
and then it is a primary problem for the management of geomorphological risk. Along the Adriatic Coast of south Italy, Petacciato
landslide is peculiar, since it showed 11 reactivations between 1924 and 2009. It is a deep-seated landslide, and the history
of its reactivations shows that even if generally related to quite abundant rainfall periods, there is no clear correlation
between rainfall events and reactivations. For this reason, here, an analysis based on a data-driven evolutionary modeling
technique is attempted, in order to identify an alert model based on cumulative rainfall heights. Modeling results are quite
interesting and encouraging, since they are able to provide landslide forecasting whereas no false positive are ever returned.
This work shows the results of this attempt as well as an analysis of the input to the modeling approach, in order to identify
which are those cumulative rainfall heights which are physically sound with respect to the particular landslide. 相似文献
172.
Several authors have claimed for correlations between surges (dark features) and various kinds of solar emissions (radio, microwave, X-ray). In this paper we propose a model to explain such correlations, in particular presenting the properties of the instabilities resulting from the coupling between material flow, connected to the appearance of a surge, and magnetic field topology. As a consequence of such instability a turbulent energy cascade to small characteristic lengths grows up. Depending of the relevant parameters of the surge (dark feature), different regimes can be found, producing different levels of electrons acceleration and mass motion deceleration. We try then to correlate the different developments of the instability with the behavior observed in type I and type III radio bursts related to surges.Proceedings of the Second CERSA Workshop on Particle Acceleration and Trapping in Solar Flares, held at Aubigny-sur-Nère (France), 23–26 June, 1986. 相似文献
173.
Vincenzo Ripepi 《Astrophysics and Space Science》2003,284(1):69-72
We present time series observations of the intermediate mass Pre-Main Sequence star H254 belonging to the young star cluster IC 348 and of the Herbig Ae star V351 Ori.Both these stars present light variation on short time scale (a few hours) typical of the Scuti pulsation. The new data are briefly described together with the plan for future observational campaigns on PMS Scuti stars. 相似文献
174.
Luciano Telesca Gerardo Colangelo Vincenzo Lapenna Maria Macchiato 《International Journal of Earth Sciences》2005,94(2):285-300
Fractal tools have been used to investigate the time dynamics of hourly self-potential data, recorded during the year 2001 by five geoelectrical stations located in one of the most seismic areas of southern Italy. Scaling behaviour has been revealed by means of different statistics: the Lomb Periodogram method, the Detrended Fluctuation Analysis, the Higuchi analysis and the mean distance spanned within the time L. The values of the scaling exponents estimated by means of these methods indicate that the temporal fluctuations of the geoelectrical signals are not typical of purely random stochastic processes (i.e. white noise), but evidence the presence of long-range correlations. Furthermore, it is found that these correlations are linear. 相似文献
175.
Andrea Dini Gianfranco Di Vincenzo Giovanni Ruggieri Jeffrey Rayner Pierfranco Lattanzi 《Mineralium Deposita》2005,40(3):337-346
The Monte Ollasteddu deposit represents a major gold discovery in the Variscan basement of southeastern Sardinia. Gold occurs
in late-Variscan extensional brittle structures hosted by meta-volcanic, and subordinately meta-sedimentary, rocks. The vein
mineralogy is dominated by quartz; arsenopyrite is the main sulphide. Reconnaissance 40Ar–39Ar dating gives ages around ∼260 Ma on K-feldspar from mineralized veins, whereas metamorphic white mica from the host rock
gives ages clustering at ∼307 Ma. The best age estimate for biotite from a nearby leucogranite body is 286.3±2.2 Ma. The Pb
isotope signature of ore and gangue minerals is entirely consistent with literature data for Variscan deposits of Sardinia,
and for European Variscan gold deposits. Fluid inclusion data point to the presence of both CO2-bearing and CO2-free fluids, with homogenization temperatures ranging from 220 to 415°C, with low-to-moderate salinities (0.4–6.2 wt% NaCl
equivalent). Monte Ollasteddu shows several features similar to European Variscan gold deposits; however, the age of mineralization
might post-date granitoid intrusion by as much as 30 Ma, being instead coeval with very late calc-alkaline basaltic dykes,
marking the transition to a post-orogenic, pre-Tethyan geodynamic setting.
Electronic Supplementary Material Supplementary material is available for this article at 相似文献
176.
Vincenzo Minganti Renzo Capelli Giuliana Drava Rodolfo De Pellegrini Giorgio Brunialti Paolo Giordani Paolo Modenesi 《Journal of Atmospheric Chemistry》2003,45(3):219-229
The concentrations of Cd, Cu, Mn, Ni, Pb, V, and Zn were measured in four different species of lichens (Parmelia caperata, P. pastillifera, P. saxatilis, P. sulcata) sampled in North-West Italy, in order to obtain maps showing metal distribution and the degree of deviation from background (natural) conditions. Significant differences among the species were found for Zn, Mn, Pb and V, suggesting that the combined use of mixed species in biomonitoring surveys can affect the interpretation of results. Results obtained for Parmelia caperata samples have been compared with background (natural) levels, and maps showing the distribution of each metal expressed as deviation from background levels have been obtained. Overall such maps show a medium to high alteration degree in the study area. 相似文献
177.
Luciano Telesca Vincenzo CuomoVincenzo Lapenna Maria Macchiato 《Physics of the Earth and Planetary Interiors》2002,131(1):47-62
We investigate the time dynamics of worldwide volcanic activity in order to find the presence of time correlation structures, by applying the Fano factor (FF) method. The analysis, performed on 35 time-occurrence volcanic eruptive sequences with volcanic explosivity index (VEI≥0) has revealed fractal behaviors in the most of the data sets considered, with fractal exponent α ranging from ∼0.2 to 0.9. 相似文献
178.
We present the photoelectric observations of the asteroids 26 Proserpina, 194 Prokne, 287 Nephthys, and 554 Peraga, performed in the years 1977–1978 at the Astronomical Observatory of Torino. The resulting synodic rotation periods are, for Proserpina, 13h13; Prokne, 15h67; and Peraga, 13h63. The period of Nephthys is possibly ~7h or the double. A tentative value for the phase coefficient of Peraga was found: 0.043 mag/degree. 相似文献
179.
Removal of Pb2 ,Cu~(2 ),Zn~(2 )and Cd~(2 )from aqueous solutions by sorption on a natural phosphate rock(FAP)was investigated.The effects of the contact time and initial metal concentration were examined in the batch method.The percentage sorption of heavy metals from solution ranges generally between 50% and 99%.The amount of sorbed metal ions follows the order Cu>Pb>Cd>Zn. Heavy metal immobilization was attributed to both surface complexation of metal ions on the surface of FAP grains and partial dissolution and precipitation of a heavy metal-containing phosphate.The very low desorption ratio of heavy metals further supports the effectiveness of FAP as an alternative and low-cost material to remove toxic Pb~(2 ),Cu~(2 ),Zn~(2 )and Cd~(2 )from polluted waters. 相似文献
180.
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