The Hardy-Landau-Littlewood inequalities with less smoothness.
The Harmonic Functions of Mean Ergodic Markov Semigroups.
The H-theorem for Boltzmann type equations.
The Kneser property for the abstract Cauchy problem
We establish existence of mild solutions for the semilinear first order functional abstract Cauchy problem and we prove that the set of mild solutions of this problem is connected in the space of continuous functions.
The linear-quadratic optimal control problem for delay differential equations
In questo lavoro si considera il problema del controllo ottimo per un'equazione lineare con ritardo in uno spazio di Hilbert, con costo quadratico. Si dimostra che il problema della sintesi si traduce in una equazione di Riccati in uno opportuno spazio prodotto e si prova che tale equazione ammette un’unica soluzione.
The martingale problem for a class of pseudo differential operators.
The Method of Stationary Phase for Once Integrated Group
The norm convergence of a Magnus expansion method
We consider numerical approximation to the solution of non-autonomous evolution equations. The order of convergence of the simplest possible Magnus method is investigated.
The norm estimate of the difference between the Kac operator and Schrödinger semigroup. II: The general case including the relativistic case.
The operator equation AX - XB = C with unbounded operators A and B and related abstract Cauchy problems.
The Ornstein-Uhlenbeck generator perturbed by the gradient of a potential
Si considera, in uno spazio di Hilbert l'operatore lineare , dove è un operatore negative autoaggiunto e è un potenziale che soddisfa a opportune condizioni di integrabilità. Si dimostra con un metodo analitico che è essenzialmente autoaggiunto in uno spazio e si caratterizza il dominio della sua chiusura come sottospazio di . Si studia inoltre la «spectral gap property» del semigruppo generato da .
The parabolic mixed Cauchy-Dirichlet problem in spaces of functions which are hölder continuous with respect to space variables
We give a new proof, based on analytic semigroup methods, of a maximal regularity result concerning the classical Cauchy-Dirichlet's boundary value problem for second order parabolic equations. More specifically, we find necessary and sufficient conditions on the data in order to have a strict solution which is bounded with values in (0 < < 1), with bounded with values in .
The Projection onto the Center of Operators in a Banach Lattice.
The RAGE theorem in Banach spaces.
The Rockland condition for nondifferential convolution operators II
The Second Half-With a Quarter of a Century Delay
We show how results by Diekmann et al. (2007) on the qualitative behaviour of solutions of delay equations apply directly to a resource-consumer model with age-structured consumer population.
The semigroup of Fredholm operators.
The Sobolev-Besov imbedding theorem from the viewpoint of semi-groups of operators
The solution operator for a partial differential equation with delay
Viene dimostrata l’esistenza e l’unicità globale della soluzione di un’equazione funzionale in uno spazio di Hilbert e si caratterizza il generatore infinitesimale del semigruppo ad essa associato. Il risultato è applicato ad equazioni integrodifferenziali a derivate parziali di tipo parabolico in cui compaiono argomenti con ritardo (discreto e continuo) nelle derivate spaziali di ordine massimo.
The spectral mapping theorem for evolution semigroups on spaces of vector-valued functions.