Search results for "Matematica"

Coherence Checking and Propagation of Lower Probability Bounds

2003

In this paper we use imprecise probabilities, based on a concept of generalized coherence (g-coherence), for the management of uncertain knowledge and vague information. We face the problem of reducing the computational difficulties in g-coherence checking and propagation of lower conditional probability bounds. We examine a procedure, based on linear systems with a reduced number of unknowns, for the checking of g-coherence. We propose an iterative algorithm to determine the reduced linear systems. Based on the same ideas, we give an algorithm for the propagation of lower probability bounds. We also give some theoretical results that allow, by suitably modifying our algorithms, the g-coher…

Efficacia di un intervento didattico innovativo per il potenziamento del problem solving sugli studenti di origine straniera

2018

Obiettivo del presente contributo è valutare l’efficacia di un intervento didattico innovativo, basato su evidenze di ricerca, nel migliorare le competenze di problem solving degli studenti degli ultimi due anni di scuola primaria, con particolare riferimento alla tipologia di origine degli stessi. Dopo una breve panoramica sul quadro teorico e sul modello di apprendimento adottato, verrà esplicitata l’impostazione metodologica alla base dell’intervento e saranno descritti i risultati. L’analisi di quest’ultimi ha evidenziato differenze significative negli esiti degli studenti che hanno partecipato alla ricerca, indipendentemente dalla tipologia di origine, e pertanto contribuisce a denotar…

Fleet deployment e routing design nel trasporto marittimo veloce dei passeggeri tra la Sicilia e le Isole Minori

2009

Intermittent and passivity based control strategies for a hyperchaotic system

2013

In this paper a four-dimensional hyperchaotic system with only one equilibrium is consid- ered and it is shown how the control and the synchronization of this system can be realized via two different control techniques. Firstly, we propose a periodically intermittent con- troller to stabilize the system states to the equilibrium and to achieve the projective syn- chronization of the system both in its periodic and hyperchaotic regime. Then, based on the stability properties of a passive system, we design a linear passive controller, which only requires the knowledge of the system output, to drive the system trajectories asymptoti- cally to the origin. Using the same passivity-based method, …

Local spectral theory for Drazin invertible operators

2016

Abstract In this paper we investigate the transmission of some local spectral properties from a bounded linear operator R, as SVEP, Dunford property (C), and property (β), to its Drazin inverse S, when this does exist.

Prove nazionali di matematica. Prepariamoci alle prove INVALSI.

2011

Deformed quons and bi-coherent states

2017

We discuss how a q-mutation relation can be deformed replacing a pair of conjugate operators with two other and unrelated operators, as it is done in the construction of pseudo-fermions, pseudo-bosons and truncated pseudo-bosons. This deformation involves interesting mathematical problems and suggests possible applications to pseudo-hermitian quantum mechanics. We construct bi-coherent states associated to $\D$-pseudo-quons, and we show that they share many of their properties with ordinary coherent states. In particular, we find conditions for these states to exist, to be eigenstates of suitable annihilation operators and to give rise to a resolution of the identity. Two examples are discu…

Pseudo-Bosons from Landau Levels

2010

We construct examples of pseudo-bosons in two dimensions arising from the Hamiltonian for the Landau levels. We also prove a no-go result showing that non-linear combinations of bosonic creation and annihilation operators cannot give rise to pseudo-bosons.

A no-go result for the quantum damped harmonic oscillator

2019

Abstract In this letter we show that it is not possible to set up a canonical quantization for the damped harmonic oscillator using the Bateman Lagrangian. In particular, we prove that no square integrable vacuum exists for the natural ladder operators of the system, and that the only vacua can be found as distributions. This implies that the procedure proposed by some authors is only formally correct, and requires a much deeper analysis to be made rigorous.

kq-Representation for pseudo-bosons, and completeness of bi-coherent states

2017

We show how the Zak $kq$-representation can be adapted to deal with pseudo-bosons, and under which conditions. Then we use this representation to prove completeness of a discrete set of bi-coherent states constructed by means of pseudo-bosonic operators. The case of Riesz bi-coherent states is analyzed in detail.