Istituto per le Applicazioni del Calcolo
"Mauro Picone"
Working paper
IMPROVING SOLVE TIME OF AGGREGATION-BASED ADAPTIVE AMG |
This paper proposed improving the solve time of the bootstrap AMG proposed previously by the authors. This is achieved by incorporating the information, set of algebraically smooth vectors, generated by the bootstrap algorithm, in a single hierarchy by using sufficiently large aggregates, and these… | |
the hilbert transform in signal processing |
Convergence of new quadrature rules for approximating the Hilbert transform are given. Numerical tests show the goodness of such approximations | |
Why diffusion-based preconditioning of Richards equation works: spectral analysis and computational experiments at very large scale. |
We consider here a cell-centered finite difference approximation of the Richards equation in three dimensions, averaging for interface values the hydraulic conductivity, a highly nonlinear function, by arithmetic, upstream and harmonic means. The nonlinearities in the equation can lead to changes… | |
Altered brain criticality in Schizophrenia: New insights from MEG |
Schizophrenia has a complex etiology and symptomatology that is difficult to untangle. After decades of research, important advancements towards a central biomarker are still lacking. One of the missing pieces is a better understanding of how non-linear neural dynamics are altered in this patient… | |
The role of long distance contribution to the B->K(*)l+l- in the Standard Model |
We investigate rare semileptonic B->K*l+l- by looking at the long distance contributions. Our analysis is limited to the very small values of physical accessible range of invariant mass of the leptonic couple q2. We show that the light quarks loop has to be accounted for, along with the charming… | |
Numerical assessment of a subglacial lake at Svalbard, Spitzbergen |
The likelihood of a subglacial lake beneath Amundsenisen Plateau at Southern Spitzbergen, Svalbard, pointed out by the flat signal within the Ground Penetrating Radar (GPR) remote survey of the area, is justified, here, via numerical simulation. This investigation has been developed under the… | |
Automatic coarsening in Algebraic Multigrid utilizing quality measures for matching-based aggregations Pasqua D'Ambra, Fabio Durastante, Salvatore Filippone, Ludmil Zikatanov |
In this paper, we discuss the convergence of an Algebraic MultiGrid (AMG) method for general symmetric positive-definite matrices. The method relies on an aggregation algorithm, named coarsening based on compatible weighted matching, which exploits the interplay between the principle of compatible… | |
(Real-Time) Embedded (ELF band) FSK-PSK Demodulator based on Hilbert Transform |
This paper describes a signal processing application an embedded hardware platform, based on Hilbert transform method for demodulation of digital signals. | |
Evaluating the impact of increasing temperatures on changes in Soil Organic Carbon stocks: sensitivity analysis and non-standard discrete approximation |
A novel model is here introduced for theSOC change indexdefinedas the normalized difference between the actual Soil Organic Carbon and thevalue assumed at an initial reference year. It is tailored on the RothC carbonmodel dynamics and assumes as baseline the value of the SOC… | |
An in-vivo validation of ESI methods with focal sources |
Electrical source imaging (ESI) aims at reconstructing the electrical brain activity from measurements of the electric field on the scalp. Even though the localization of single focal sources should be relatively straightforward, different methods provide diverse solutions due to the different… |
