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1.
Comparing generalized Pareto models fitted to extreme observations: an application to the largest temperatures in Spain 总被引：1，自引：1，他引：0
Andrés M. Alonso Patricia de Zea Bermudez Manuel G. Scotto 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(5):1221-1233
In this paper, a subsampling-based testing procedure for the comparison of the exceedance distributions of stationary time series is introduced. The proposed testing procedure has a number of advantages including the fact that the assumption of stationary can be relaxed for some specific forms of non-stationary and also that the two time series are not required to be independently-generated. For this purpose, a test based on the Kolmogorov–Smirnov and the L 1-Wasserstein distances between generalized Pareto distributions is introduced and studied in some detail. The performance of the testing procedure is illustrated through a simulation study and with an empirical application to a set of data concerning daily maximum temperature in the 17 autonomous communities of Spain for the period 1990–2004. The autonomous communities were clustered according to the similarities of the fitted generalized Pareto models and then mapped. The cluster analysis reveals a clear distinction between the four northeast communities on the shores of the Bay of Biscay (which are the regions exhibiting milder temperatures) and the remaining regions. A second cluster corresponds to the southern Mediterranean area and the central region which corresponds to the communities with highest temperatures. 相似文献
2.
Martins Ana Rafael Sandra Monteiro Alexandra Scotto Manuel Gouveia Sónia 《Mathematical Geosciences》2019,51(8):1021-1035
Mathematical Geosciences - EURO-CORDEX is an international initiative which provides regional climate projections based on multiple dynamical and empirical–statistical downscaling models. The... 相似文献
3.
Nicola Nocilla Aldo Evangelista Anna Scotto di Santolo 《Rock Mechanics and Rock Engineering》2009,42(5):815-833
In recent years, rock fall phenomena in Italy have received considerable attention for risk mitigation through in situ observations
and experimental data. This paper reports the study conducted at Camaldoli Hill, in the urban area of Naples, and at Monte
Pellegrino, Palermo, Italy. The rocks involved are volcanic Neapolitan yellow tuff (NYT) in the former area and dolomitic
limestone in the latter. Both rocks, even though with different strength characteristics, have shown a significant tendency
towards rock fragmentation during run out. This behavior was first investigated by comparing the volumes of removable blocks
on the cliff faces (V
0) and fallen blocks on the slopes (V
f). It was assumed that the ratio V
f/V
0 decreases with the distance (x
f) from the detachment area by an empirical law, which depends on a coefficient α, correlated with the geotechnical properties of the materials involved in the rock fall. Finally, this law was validated
by observation of well-documented natural rock falls (Palermo) and by in situ full-scale tests (Naples). From the engineering
perspective, consideration of fragmentation processes in rock fall modeling provides a means for designing low-cost mitigation
measures. 相似文献
4.
Some observations on the prediction of the dynamic parameters of debris flows in pyroclastic deposits in the Campania region of Italy 总被引：1，自引：0，他引：1
Over the last 20 years, many tools have been developed for the prediction of the post-failure behaviour of rapid landslides.
However, as pointed out by several researchers, knowledge may be improved by the performance of back-analyses using different
models and the evaluation of their reliability. This paper reports the back-analysis, conducted using numerical models, of
57 rapid landslides that have occurred in the Campania region. The back-analysis has been performed using the 2-D DAN_W code
(version 2003) with two different rheological models: the Voellmy and the frictional models. The latter has been immediately
discarded because it did not match the observed data. Instead, using the Voellmy model, the best-fit values of the parameters
(friction μ and turbulence ξ) for different types of flow (channelled, un-channelled and mixed flows) have been researched.
With these values a parametric study has been carried out on four representative slope profiles of the Campania region, enabling
the prediction of runout, velocity and depth of flow (dynamic parameters) of potential debris flows.
相似文献
| Anna Scotto di SantoloEmail: |
5.
6.
Autoscala: an aid for different ionosondes 总被引：1，自引：1，他引：0
Michael Pezzopane Carlo Scotto Łukasz Tomasik Igor Krasheninnikov 《Acta Geophysica》2010,58(3):513-526
Autoscala is a software to automatically scale ionospheric characteristics from an ionogram. Initially it was only applied
to the ionograms recorded by the AIS-INGV ionosondes installed at Rome and Gibilmanna (Italy), and Tucumán (Argentina), that
are not able to record the polarization of the received echo. Recently, Autoscala was also applied to the ionograms recorded
by the AIS-Parus ionosonde installed at Moscow (Russia), that is not able to tag the received echo in terms of polarization,
and by the VISRC2 ionosonde installed at Warsaw (Poland) that is instead able to perform the polarization tagging of the ordinary
and extraordinary echoes. This work shows different examples of processing performed on ionograms recorded by all these three
different types of ionosondes. 相似文献
7.
Linear autoregressive models and non-linear threshold autoregressive (TAR) models are used in the present work to describe the time series of the significant wave height of sea-states at Figueira da Foz, located in the Portuguese coast. The seasonal components of this series are identified and a TAR model with two regimes is proposed. A simulation study was carried out with the purpose of verifying if both the non-linear and linear models are suited to describe the probabilistic structure of the process. It is shown that both methods are adequate to describe the lower statistical moments of the original data, but the non-linear model represents better the skewness and the kurtosis of the data. 相似文献
8.
In normal practice, the active earth pressure on cantilever retaining wall is evaluated with different procedures relating to an ideal vertical plane passing through the heel of the wall. If the wall presents a long heel, failure planes do not interfere with the vertical stem, so that the limit Rankine conditions can develop freely in the backfill. The inclination of lateral actions along the ideal plane is assumed to be constant and depends on the geometry of the ground level and on the friction angle φ. The Authors recently proposed a new method to evaluate the active earth pressure coefficient due to seismic loading with a pseudo-static stress plasticity solution. The present paper describes the application of this method to a retaining wall supporting a φ soil backfill with an irregular surface. For two different configurations of wall-soil system, the behaviour is also studied by continuum FDM dynamic analyses, utilising four Italian accelerometric time-histories scaled at the same peak ground acceleration. The comparison between different procedures is also analysed. 相似文献
9.
10.
Long (>30 years) monthly records of relative sea-level heights from tide gauges in the Baltic sea are analyzed. Time series clustering based on forecast densities is applied in order to describe regional sea-level variability in the Baltic Sea in terms of future relative heights. The tide gauge records are clustered on the basis of forecasts at 3-month and 6-month horizons. For the 3-month horizon, the results of the cluster analysis show a fairly spatial coherency in terms of grouping together locations from the same sub-basin, with the northern records in the Bothnian Sea and Gulf of Finland clustering together, followed by the tide gauges in the Baltic Proper and lastly the southernmost stations in the western Baltic. For the 6-month horizon, the results show a higher degree of homogeneity between different locations, but a clear separation between the stations at the Baltic entrance and the tide gauges inside the Baltic basin. Moreover, when considering detrended records, reflecting mainly the seasonal cycle, the clustering results are more homogeneous and suggest a distinct response of coastal sea-level in spring and in summer. 相似文献