Articolo in rivista

Time and space analysis of two earthquakes in the Appennines (Italy)

In this paper, we study two earthquakes: the April 6th 2009 earthquake of L'Aquila in the re-gion of Abruzzo (Italy) and the 1997 Colfiorito earthquake in the regions of Umbria and Marche (Italy). The data sets of these two earthquakes were analysed in both time and space domains. For time domain…

Non hydrodynamic modes in shell models of turbulence: a Lattice Boltzmann study

A lattice Boltzmann scheme simulating the dynamics of shell models of turbulence is developed. The influence of high-order kinetic modes (ghosts) on the dissipative properties of turbulence dynamics is studied. It is analytically found that when ghost fields relax on the same timescale as the…

Uniform weighted approximation on the square by polynomial interpolation at Chebyshev nodes

The paper deals with de la Vallee Poussin type interpolation on the square at tensor product Chebyshev zeros of the first kind. The approximation is studied in the space of locally continuous functions with possible algebraic singularities on the boundary, equipped with weighted uniform norms. In…

Domain derivative approach to active infrared thermography

A thin conducting plate has an inaccessible side in contact with aggressive external agents. On the other side, we are able to heat the plate and take temperature maps in laboratory conditions. Detecting and evaluating damages on the inaccessible side from thermal data requires the solution of a…

Kerr metric, static observers and Fermi coordinates

The coordinate transformation which maps the Kerr metric written in standard Boyer-Lindquist coordinates to its corresponding form adapted to the natural local coordinates of an observer at rest at a fixed position in the equatorial plane, i.e., Fermi coordinates for the neighborhood of a static…

On the limit as $s\to 1^-$ of possibly non-separable fractional Orlicz-Sobolev spaces

Extended versions of the Bourgain-Brezis-Mironescu theorems on the limit as s->1^- of the Gagliardo-Slobodeckij fractional seminorm are established in the Orlicz space setting. Our results hold for fractional Orlicz-Sobolev spaces built upon general Young functions, and complement those of [13…

The independent Component Analysis as a new tool to determine solvent content in protein crystals

Estimating the solvent content in protein crystals is one of the first steps in a macromolecular structure determination. We apply a new statistical technique, the independent component analysis (ICA), to determine the volume fraction of the asymmetric unit of proteins occupied by the solvent. The…

Rayleigh and Prandtl number scaling in the bulk of Rayleigh-Bénard turbulence

The Ra and Pr number scaling of the Nusselt number Nu, the Reynolds number Re, the temperature fluctuations, and the kinetic and thermal dissipation rates is studied for (numerical) homogeneous Rayleigh–Bénard turbulence, i.e., Rayleigh–Bénard turbulence with periodic boundary conditions in all…

Identification of time-varying inaccessible thermal conductance from data at the boundary

A composite specimen, made of two slabs and an interface A is heated through one of its sides S, in order to evaluate the thermal conductance H of A. The direct model consists of a system of Initial Boundary Value Problems completed by suitable transmission conditions. Thanks to the properties of…

Laguerre-type exponentials and generalized Appell polynomials

General classes of two variables Appell polynomials are introduced by exploiting properties of an iterated isomorphism, related to the so-called Laguerre-type exponentials. Further extensions to the multi-index and multivariable cases are mentioned. (C) 2004 Elsevier Ltd. All rights reserved.