A5050725909- Advanced Numerical Methods in Computational Mathematics
- Numerical methods in engineering
- Lattice Boltzmann Simulation Studies
- Advanced Mathematical Modeling in Engineering
- Computational Fluid Dynamics and Aerodynamics
- Advancements in Semiconductor Devices and Circuit Design
- Thermal properties of materials
- earthquake and tectonic studies
- Nanowire Synthesis and Applications
- Numerical methods in inverse problems
- Differential Equations and Numerical Methods
- Seismic Imaging and Inversion Techniques
- Electromagnetic Simulation and Numerical Methods
- Seismic Waves and Analysis
- Geophysical and Geoelectrical Methods
- Geological and Geochemical Analysis
- Computer Graphics and Visualization Techniques
- Earthquake Detection and Analysis
- Fluid Dynamics and Turbulent Flows
- High-pressure geophysics and materials
- Computational Geometry and Mesh Generation
- Particle accelerators and beam dynamics
- Mathematical Approximation and Integration
- Gas Dynamics and Kinetic Theory
- Soil and Unsaturated Flow
University of Catania
2013-2024
Oxford Brookes University
2016-2023
University of Bristol
2014-2016
Queen's University
2016
University of Bari Aldo Moro
2014
Abstract. Ground deformation and gravity changes in restless calderas during periods of unrest can signal an impending eruption thus must be correctly interpreted for hazard evaluation. It is critical to differentiate variation geophysical observables related volume pressure induced by magma migration from shallow hydrothermal activity associated with hot fluids magmatic origin rising depth. In this paper we present a numerical model evaluate the thermo-poroelastic response system caldera...
Abstract We propose a finite-difference ghost-point approach for the numerical solution of Cauchy-Navier equations in linear elasticity problems on arbitrary unbounded domains. The technique is based smooth coordinate transformation, which maps an domain into unit square. Arbitrary geometries are defined by suitable level-set functions. discretized classical nine-point stencil interior points, while boundary conditions and high order reconstructions used to define field variables at...
In this paper, we describe how to construct a finite-difference shockcapturing method for the numerical solution of Euler equation gas dynamics on arbitrary two-dimensional domain Ω, possibly with moving boundary.The boundaries are assumed be changing due movement solid objects/obstacles/walls.Although motion boundary could coupled fluid, all tests performed assuming that such is prescribed and independent fluid flow.The based discretizing regular Cartesian grid in rectangular Ω R ⊃ Ω.We...
Geophysical techniques are widely used to monitor volcanic unrest. A number of studies have also demonstrated that hydrological processes can produce or trigger geophysical signals. Hydrologically induced gravity signals previously been recorded by specifically designed surveys as well as, inadvertently, volcano monitoring studies. Water table corrections microgravity commonplace. However, the fluctuations water beneath survey locations often poorly known, and such a correction fails account...
Efficient and accurate hydrothermal mechanical mathematical models in porous media constitute a fundamental tool for improving the understanding of subsurface dynamics volcanic areas. We propose finite-difference ghost-point method numerical solution thermo-poroelastic gravity change equations. The main aim this work is to study how solutions vary realistic description specific region, focusing on topography heterogeneous structure Campi Flegrei (CF) caldera (Italy). Our approach provides...
We present a Boundary Local Fourier Analysis (BLFA) to optimize the relaxation parameters of boundary conditions in multigrid framework. The method is implemented solve elliptic equations on curved domains embedded uniform Cartesian mesh, although it designed be extended for general PDEs domains, wherever technique can implemented. implicitly defined by level-set function and ghost-point employed treat conditions. Existing strategies literature adopt constant parameter whole boundary. In...
Abstract Pre‐eruptive signals at the crater lake‐bearing Mt. Ruapehu (New Zealand) are either absent or hard to identify. Here, we report on geophysical anomalies arising from hydrothermal unrest (HTU) and magmatic (MU) using multiphysics numerical modeling. Distinct spatio‐temporal revealed when jointly solving for ground displacements changes in gravitational electrical potential fields a set of subsurface disturbances including magma recharge anomalous flow. Protracted injections induce...
Silicon nanowires (SiNWs) are quasi-one-dimensional structures in which electrons spatially confined two directions and they free to move the orthogonal direction. The subband decomposition electrostatic force field obtained by solving Schrödinger–Poisson coupled system. electron transport along direction can be tackled using a hydrodynamic model, formulated taking moments of multisubband Boltzmann equation. We shall introduce an extended model where closure relations for fluxes production...
Abstract. Ground deformation and gravity changes in active calderas during periods of unrest can signal an impending eruption thus must be correctly interpreted for hazard evaluation. It is critical to differentiate variation geophysical observables related volume pressure induced by magma migration from shallow hydrothermal activity associated with hot fluids magmatic origin rising depth. In this paper we present a numerical model evaluate the thermo-poroelastic response system caldera...
Abstract The requirements for future accelerator chains need to increase the injected beam brilliance significantly, still keeping high quality in terms of reliability, reproducibility and stability. A roadmap ion source development may consist several steps: plasma simulation, multiphysics simulation each system component, high-level control system, characterization, data analysis and, again, simulation. cycle starts ends with because it is instrument that shows how different phenomena take...
In this paper a fourth order finite difference ghost point method for the Poisson equation on regular Cartesian mesh is presented. The can be considered high extension of second introduced earlier by authors. Three different discretizations are considered, which differ in stencil that discretizes Laplacian and source term. It shown only two them provide stable method. accuracy such methods numerically verified several test problems.
In this paper, a comparative study between the Coco-Russo scheme (based on finite-difference scheme) and $\mathghost$-FEM finite-element method) is presented when solving Poisson equation in arbitrary domains. The comparison two numerical methods carried out by presenting analytical results from literature \cite{cocoStissi,astuto2024nodal}, together with tests various geometries boundary conditions.
Abstract In this article, a fourth-order finite-difference ghost-point method for the Poisson equation on regular Cartesian mesh is presented. The can be considered high-order extension of second-order ghost introduced earlier by authors. Three different discretizations are considered, which differ in stencil that discretizes Laplacian and source term. It shown only two them provide stable method. accuracy such methods numerically verified several test problems.
We present a theoretical study of the low-field electron mobility in rectangular gated silicon nanowire transistors at 300 K based on hydrodynamic model and self-consistent solution Schrodinger Poisson equations. The has been formulated by taking moments multisubband Boltzmann equation, closed basis Maximum Entropy Principle. It includes scattering electrons with acoustic non-polar optical phonons surface roughness scattering.
In this paper we present a multigrid approach to solve the Poisson equation in arbitrary domain (identified by level set function) and mixed boundary conditions. The discretization is based on finite difference scheme ghost-cell method. This strategy can be applied also more general problems where non-eliminated condition used. Arbitrary make definition of restriction operator for conditions hard find. A suitable provided work, together with proper treatment smoothing, order avoid...
When approximating elliptic problems by using specialized approximation techniques, we obtain large structured matrices whose analysis provides information on the stability of method. Here provide spectral and norm estimates for matrix sequences arising from Laplacian via ad hoc finite differences. The involves several tools theory in particular setting Toeplitz operators Generalized Locally sequences. Several numerical experiments are conducted, which confirm correctness theoretical findings.