Le Matematiche  

Julian Janus

We prove existence of Carathéodory type selections for multifunctions of two variables which are weakly lower semicontinuous with respect to one variable and measurable with respect to the other.

Riccardo De Arcangelis

One of the results proved is the following: if (fh ) is a sequence of K-quasiregular mappings, converging to f  in L1loc, whose jacobians verify a weak integrability condition, then the solutions of Dirichlet problems for the nonlinear Laplace-Beltra... see more

Marino De Luca

In the framework of continuum models, a system-optimization problem for transportation networks is studied in nonlinear case. Some results of convex analysis are used to prove the existence theorems and to derive variational inequalities for optimal flow.... see more

Vincenzo Ferone

Let w be a weak solution of the Neumann problem for a second order elliptic equation in divergence form, in abounded open subset G of Rn . In the case that the right hand side of the equation is a continuous linear functional on H1(G) , we give some symme... see more

Luigia Berardi

In this paper we prove that a total n-spread of PG(2n+1,q) gives us a new 3-design. Moreover, in the case n=1 we construct some new 2-design using spreads.

Alberto Alzati

Let V be a Fano threefold of genus one (i.e. with Pic(V)?Z). Let G be the Grassmannian of the lines of P4 . We study when it is possible to embed V in G , in such cases we determine the cohomology class of V in H*(G).

Ottavio Caligaris

We find here a representation of convex regularization of a non convex proper function and of a non convex proper normal integrand by means of a suitable multifunction which reveals to be very useful in existence theorems for non convex problems of calcul... see more

Ottavio Caligaris

In this note we give some existence theorems for integral functionals with non convex integrand. We consider first the simpler case in which minimization is taken on decomposable spaces and successively we prove an existence theorem also for the minimum o... see more

Giovanni Russo

The evolution laws of ordinary discontinuity and characteristic shacks are derived using the kinematic and geometric of singular surfaces. Application to contact discontinuity in gas dynamics and to Alfvén shocks are made.

Giuseppe Tomaselli

We prove the continuous dependence of z, the solution of the Darboux problem for the equation zxy+A(x,y)zx+B(x,y)zy+C(x,y)z=f(x,y), on the coefficients A,B,C. Here, z belongs to a Sobolev space and A,B,C verify some rather general assumptions (which do no... see more

Santo Motta, Giovanni Russo, Hardy Moock, Joachim Wick

We present a point approximation method of a space homogeneous transport equation. A number-theoretical convergence proof of the method is given.

Danut Marcu

The aim of this paper is to solve a problem of Capobianco and Molluzzo [2, pag. 65]. More exactly, we show that for any two integers n and m, 1there exists a graph G, such that k(G)=n and k[L(G)]=m, where k(G) denotes the connectivity of G , and L(G) the ... see more

Luisa Fattorusso

See directly the article.

Rita Ceppitelli, Massimo Villarini

The purpose of this paper is to obtain a theoretical estimate of the effect of a nonlinear perturbation on the solution of a boundary value problem for quasilinear hyperbolic systems in bicharacteristic canonic form with the same boundary data which L. Ce... see more