Articolo in rivista

Numerical Insights in the Solution of Euler Equations of the Variational Image Segmentation

Evaluating the impact of increasing temperatures on changes in Soil Organic Carbon stocks: sensitivity analysis and non-standard discrete approximation

The SOC change index, defined as the normalized difference between the actual Soil Organic Carbon and the value assumed at an initial reference year, is here tailored to the RothC carbon model dynamics. It assumes as a baseline the value of the SOC equilibrium under constant environmental…

Mechanisms and nucleation rate of methane hydrate by dynamical nonequilibrium molecular dynamics

We investigate the effects of high solvated-methane concentration on methane-hydrate nucleation at 250 K and 500 atm. We consider solutions at four levels of methane molar fraction in the initial H2O-CH4 solution, ?CH4 = 0.038, 0.044, 0.052, and 0.058, which are higher than (metastable) bulk…

Particle scattering by a test fluid on a Schwarzschild spacetime: the equation of state matters

The motion of a massive test particle in a Schwarzschild spacetime surrounded by a perfect fluid with equation of state $p_0= w \rho_0$ is investigated. Deviations from geodesic motion are analyzed as a function of the parameter $w$, ranging from $w=1$ which corresponds to the case of massive…

An approximation property of Pisot numbers

Let $q>1$. Initiated by P. Erd\H os et al. in \cite{ErdJooKom1}, several authors studied the numbers $l^m(q)=\inf \{y\ :\ y\in\Lambda_m,\ y\ne 0\}$, $m=1,2,\dots$, where $\Lambda_m$ denotes the set of all finite sums of the form $y=\eps_0 + \eps_1 q + \eps_2 q^2 + \dots + \eps_n q^n$ with…

From desk to bed: Computational simulations provide indication for rheumatoid arthritis clinical trials

Background: Rheumatoid arthritis (RA) is among the most common human systemic autoimmune diseases, affecting approximately 1% of the population worldwide. To date, there is no cure for the disease and current treatments show undesirable side effects. As the disease affects a growing number of…

Copepods encounter rates from a model of escape jump behaviour in turbulence

A key ecological parameter for planktonic copepod studies is their encounter rates within the same population as well as with other species. The encounter rate is partly determined by copepod's swimming behaviour and is strongly influenced by turbulence of the surrounding environment. A distinctive…

Convection in multiphase fluid flows using lattice Boltzmann methods

We present high-resolution numerical simulations of convection in multiphase flows (boiling) using a novel algorithm based on a lattice Boltzmann method. We first study the thermodynamical and kinematic properties of the algorithm. Then, we perform a series of 3D numerical simulations changing the…

Pointwise convergence of Fourier regularization for smoothing data

The classical smoothing data problem is analyzed in a Sobolev space under the assumption of white noise. A Fourier series method based on regularization endowed with Generalized Cross Validation is considered to approximate the unknown function. This approximation is globally optimal, i.e., the…

Seeking critical nodes in digraphs

The Critical Node Detection Problem (CNDP) consists in finding the set of nodes, defined critical, whose removal maximally degrades the graph. In this work we focus on finding the set of critical nodes whose removal minimizes the pairwise connectivity of a direct graph (digraph). Such problem has…