Search results for " Matematica"

Matematica ... a Distanza. Convinzioni, atteggiamenti e pau- re degli insegnanti di scuola Primaria: esiti di un’indagine statistica

2021

Il paper mette a fuoco gli esiti dell’indagine statistica rivolta agli insegnanti di Ma- tematica di scuola Primaria del contesto italiano, circa l’adozione della Didattica a Distanza (DaD), impiegata durante il periodo di emergenza sanitaria da Covid-19. In una prima parte si inquadra la DaD generale da un punto di vista storico e teorico-pratico e, dopo, il focus diviene l’insegnamento e l’apprendimento della Matematica, attraverso l’e-learning. In una seconda parte viene presentata la ricerca e i risultati ad essa correlati. L’indagine statistica, messa in atto attraverso un questionario, qui interamente riportato, ha avuto l’obiettivo di esaminare le rela- zioni intercorrenti tra moltep…

Mapping properties of weakly singular periodic volume potentials in Roumieu classes

2020

The analysis of the dependence of integral operators on perturbations plays an important role in the study of inverse problems and of perturbed boundary value problems. In this paper, we focus on the mapping properties of the volume potentials with weakly singular periodic kernels. Our main result is to prove that the map which takes a density function and a periodic kernel to a (suitable restriction of the) volume potential is bilinear and continuous with values in a Roumieu class of analytic functions. This result extends to the periodic case of some previous results obtained by the authors for nonperiodic potentials, and it is motivated by the study of perturbation problems for the solut…

MR3200323 Norling, Magnus Dahler, Inverse semigroup C∗-algebras associated with left cancellative semigroups. Proc. Edinb. Math. Soc. (2) 57 (2014), …

2014

Lagrangian dynamics and possible isochronous behavior in several classes of non-linear second order oscillators via the use of Jacobi last multiplier

2015

Abstract In this paper, we employ the technique of Jacobi Last Multiplier (JLM) to derive Lagrangians for several important and topical classes of non-linear second-order oscillators, including systems with variable and parametric dissipation, a generalized anharmonic oscillator, and a generalized Lane–Emden equation. For several of these systems, it is very difficult to obtain the Lagrangians directly, i.e., by solving the inverse problem of matching the Euler–Lagrange equations to the actual oscillator equation. In order to facilitate the derivation of exact solutions, and also investigate possible isochronous behavior in the analyzed systems, we next invoke some recent theoretical result…

Approximate renormalization-group transformation for Hamiltonian systems with three degrees of freedom

1999

We construct an approximate renormalization transformation that combines Kolmogorov-Arnold-Moser (KAM)and renormalization-group techniques, to analyze instabilities in Hamiltonian systems with three degrees of freedom. This scheme is implemented both for isoenergetically nondegenerate and for degenerate Hamiltonians. For the spiral mean frequency vector, we find numerically that the iterations of the transformation on nondegenerate Hamiltonians tend to degenerate ones on the critical surface. As a consequence, isoenergetically degenerate and nondegenerate Hamiltonians belong to the same universality class, and thus the corresponding critical invariant tori have the same type of scaling prop…

Nonlinear Kelvin waves on a quantized vortex line in superfluid helium

2013

In this paper we show an exact solution (Kelvin wave) of an approximated dynamical equation for a quantized vortex line in helium superfluid at finite temperature. It is shown that the applied heat flux interacts with the vortex line, and the amplitude of the Kelvin wave can grow (the so-called Donnelly instability) or decrease according with the mutual direction between heat flux and wave vector.

On modeling the immune competition with Darwinian dynamics

Mathematical and computational models are increasingly used in this century to help modeling of living systems. Mathematical modeling presents many methods for studying and analyzing the behavior of biological systems, in particular, cellular systems. As Bellomo (2008), Bellouquid and Delitala (2006), suggest " The modeling of living systems is not an easy task, it requests technically complex mathematical methods to deal with the inner complexity of biological systems which exhibit features and behaviors very different from those of inert matter". The mathematical approach used in this dissertation is based on the Kinetic Theory of Active Particles (KTAP), that has been specifically develo…

MR2865796 Riecan, Beloslav; Tkacik, Štefan A note on the Kluvánek integral. Tatra Mt. Math. Publ. 49 (2011), 59--65

2011

Fixed point iterative schemes for variational inequality problems

2018

In a wide class of evolutionary processes, the problem of computing the solutions of an initial value problem is encountered. Here, we consider projected dynamical systems in the sense of \cite{Daniele} and references therein. Precisely, a projected dynamical system is an operator which solves the initial value problem: \begin{equation}\label{PDS}\frac{dx(t)}{dt}= \Pi_{\mathbb{K}}\left(x(t),-F(x(t))\right), \quad x(0)=x_0 \in \mathbb{K}, \, t \in [0,+\infty[,\tag{P}\end{equation} where $\mathbb{K}$ is a convex polyhedral set in $\mathbb{R}^n$, $F: \mathbb{K} \to \mathbb{R}^n$ and $\Pi_{\mathbb{K}}: \mathbb{R} \times \mathbb{K} \to \mathbb{R}^n$ is given as follows $\Pi_{\mathbb{K}}(x,-F(x))…

The Duality of Entropy/Extropy, and Completion of the Kullback Information Complex

2018

The refinement axiom for entropy has been provocative in providing foundations of information theory, recognised as thoughtworthy in the writings of both Shannon and Jaynes. A resolution to their concerns has been provided recently by the discovery that the entropy measure of a probability distribution has a dual measure, a complementary companion designated as &ldquo