Search results for "Analisi Matematica"
showing 10 items of 811 documents
AN OPTIMIZATION THEOREM IN SPACES ADMITTING A CONTINUOUS BIJECTION ONTO [0,1]
2011
A note on *-derivations of partial *-algebras
2012
A definition of *-derivation of partial *-algebra through a sufficient family of ips-forms is proposed.
Monotone generalized nonlinear contractions and fixed point theorems in ordered metric spaces
2011
The purpose of this paper is to present some fixed point theorems for T -weakly isotone increasing mappings which satisfy a generalized nonlinear contractive condition in complete ordered metric spaces. As application, we establish an existence theorem for a solution of some integral equations.
Permutations of zero-sumsets in a finite vector space
2020
Abstract In this paper, we consider a finite-dimensional vector space 𝒫 {{\mathcal{P}}} over the Galois field GF ( p ) {\operatorname{GF}(p)} , with p being an odd prime, and the family ℬ k x {{\mathcal{B}}_{k}^{x}} of all k-sets of elements of 𝒫 {\mathcal{P}} summing up to a given element x. The main result of the paper is the characterization, for x = 0 {x=0} , of the permutations of 𝒫 {\mathcal{P}} inducing permutations of ℬ k 0 {{\mathcal{B}}_{k}^{0}} as the invertible linear mappings of the vector space 𝒫 {\mathcal{P}} if p does not divide k, and as the invertible affinities of the affine space 𝒫 {\mathcal{P}} if p divides k. The same question is answered also in the case where …
Dependence of effective properties upon regular perturbations
2022
In this survey, we present some results on the behavior of effective properties in presence of perturbations of the geometric and physical parameters. We first consider the case of a Newtonian fluid flowing at low Reynolds numbers around a periodic array of cylinders. We show the results of [43], where it is proven that the average longitudinal flow depends real analytically upon perturbations of the periodicity structure and the cross section of the cylinders. Next, we turn to the effective conductivity of a periodic two-phase composite with ideal contact at the interface. The composite is obtained by introducing a periodic set of inclusions into an infinite homogeneous matrix made of a di…
Two positive solutions for a nonlinear parameter-depending algebraic system
2021
The existence of two positive solutions for a nonlinear parameter-depending algebraic system is investigated. The main tools are a finite dimensional version of a two critical point theorem and a recent weak-strong discrete maximum principle.
Two positive solutions for a nonlinear parameter-depending algebraic system
2021
The existence of two positive solutions for a nonlinear parameter-depending algebraic system is investigated. The main tools are a finite dimensional version of a two critical point theorem and a recent weak-strong discrete maximum principle.
Normalized Solutions to the Fractional Schrödinger Equation with Potential
2023
AbstractThis paper is concerned with the existence of normalized solutions to a class of Schrödinger equations driven by a fractional operator with a parametric potential term. We obtain minimization of energy functional associated with that equations assuming basic conditions for the potential. Our work offers a partial extension of previous results to the non-local case.
MR3535311 Reviewed Inoue, H.(J-KYUSGM); Takakura, M.(J-FUE-AM) Regular biorthogonal pairs and pseudo-bosonic operators. (English summary) J. Math. Ph…
2017
Given a pair of operators a and b acting on a Hilbert space H, such that [a,b]=1, the authors give a method to construct a regular bi-orthogonal pair of sequences in H. They study the relationship between the conditions on a,b,a†,b† and the operators Ae,Be,A†e,B†e, considered by one of the authors in a previous paper, in the set-up of a general theory of bi-orthogonal pair sequences. Then they give a method to construct operators A and B with the so-called D-pseudo bosons conditions, i.e. the commutation rule and some assumptions, on a dense subspace D of H, considered in the literature. Finally, some physical examples are given.
Existence of positive solutions for nonlinear Dirichlet problems with gradient dependence and arbitrary growth
2018
We consider a nonlinear elliptic problem driven by the Dirichlet $p$-Laplacian and a reaction term which depends also on the gradient (convection). No growth condition is imposed on the reaction term $f(z, \cdot,y)$. Using topological tools and the asymptotic analysis of a family of perturbed problems, we prove the existence of a positive smooth solution.