A spectral mapping theorem for semigroups solving PDEs with nonautonomous past.
A spectral perturbation problem and its applications to waves above an underwater ridge.
A spectral study of an infinite axisymmetric elastic layer
We present here a theoretical study of eigenmodes in axisymmetric elastic layers. The mathematical modelling allows us to bring this problem to a spectral study of a sequence of unbounded self-adjoint operators , , in a suitable Hilbert space. We show that the essential spectrum of is an interval of type and that, under certain conditions on the coefficients of the medium, the discrete spectrum is non empty.
A spectral study of an infinite axisymmetric elastic layer
We present here a theoretical study of eigenmodes in axisymmetric elastic layers. The mathematical modelling allows us to bring this problem to a spectral study of a sequence of unbounded self-adjoint operators An, , in a suitable Hilbert space. We show that the essential spectrum of An is an interval of type and that, under certain conditions on the coefficients of the medium, the discrete spectrum is non empty.
A spectral theory for locally compact abelian groups of automorphisms of commutative Banach algebras
Let A be a commutative Banach algebra with Gelfand space ∆ (A). Denote by Aut (A) the group of all continuous automorphisms of A. Consider a σ(A,∆(A))-continuous group representation α:G → Aut(A) of a locally compact abelian group G by automorphisms of A. For each a ∈ A and φ ∈ ∆(A), the function t ∈ G is in the space C(G) of all continuous and bounded functions on G. The weak-star spectrum is defined as a closed subset of the dual group Ĝ of G. For φ ∈ ∆(A) we define to be the union of all...
A spectrality condition for infinitesimal generators of cosine operator functions
A stability result for -harmonic systems with discontinuous coefficients.
A stability theorem for convergence of a Lyapounov function along trajectories of nonexpansive semigroups.
A stability theorem of the Navier-Stokes flow past a rotating body
In this paper, a stability theorem of the Navier-Stokes flow past a rotating body is reported. Concerning the linearized problem, the proofs of the generation of a C₀ semigroup and its decay properties are sketched.
A stochastic model of symbiosis
We consider a system of stochastic differential equations which models the dynamics of two populations living in symbiosis. We prove the existence, uniqueness and positivity of solutions. We analyse the long-time behaviour of both trajectories and distributions of solutions. We give a biological interpretation of the model.
A stochastic symbiosis model with degenerate diffusion process
We present a model of symbiosis given by a system of stochastic differential equations. We consider a situation when the same factor influences both populations or only one population is stochastically perturbed. We analyse the long-time behaviour of the solutions and prove the asymptoptic stability of the system.
A stochastic version of Fan's best approximation theorem.
A Strict Maximum Modulus Theorem for Certain Banach Spaces.
A strong convergence in and upper -continuous operators
A strong convergence theorem for a common fixed point of two sequences of strictly pseudocontractive mappings in Hilbert spaces and applications.
A strong convergence theorem for a family of quasi--nonexpansive mappings in a Banach space.
A strongly degenerate quasilinear equation : the elliptic case
We prove existence and uniqueness of entropy solutions for the Neumann problem for the quasilinear elliptic equation , where , , and is a convex function of with linear growth as , satisfying other additional assumptions. In particular, this class includes the case where , , being a convex function with linear growth as . In the second part of this work, using Crandall-Ligget’s iteration scheme, this result will permit us to prove existence and uniqueness of entropy solutions for the...
A strongly diagonal power of algebraic order bounded disjointness preserving operators.
A structure theorem Lie algebras of unbounded derivations in -algebras
A structure theory for isometric representations of a class of semigroups.