1,354,794 research outputs found
Recovering a leading coefficient and a memory kernel in first-order integro-differential operator equations
No full textAbstractWe are concerned with the identification of the scalar functions a and k in the convolution first-order integro-differential equation u′(t)−a(t)Au(t)−k∗Bu(t)=f(t), 0⩽t⩽T, k∗v(t)=∫0tk(t−s)v(s)ds, in a Banach space X, where A and B are linear closed operators in X, A being the generator of an analytic semigroup of linear bounded operators. Taking advantage of two pieces of additional information, we can recover, under suitable assumptions and locally in time, both the unknown functions a and k. The results so obtained are applied to an n-dimensional integro-differential identification problem in a bounded domain in Rn
Identification of memory kernels depending on time and on an angular variable
No full textWe deal with the problem of recovering a memory kernel k(t, η), depending on time t and on an angular variable η, in a parabolic integrodifferential equation related to a toric domain. We show that the problem can be uniquely solved locally in time if the kernel k is not assumed to be necessarily periodic with respect to η. On the contrary, under a periodicity condition for k(t, ·), we show uniqueness assuming existence
Gradient estimates for solutions of parabolic differential equations degenerating at infinity
No full textFor p ∈ (1,+∞) we derive a weighted Lp estimate for the (spatial) gradient of the solution u of a degenerate parabolic differential equation. Here the underlying domain ω ⊂ Rn, n ≥ 2, is unbounded and the equation may degenerate only at infinity along some unbounded branch of ω. Our estimate is strictly related with the still-open problem of giving a concrete characterization of the interpolation space between W2,p(ω) and Lp(ω) to which the (spatial) gradient of u belongs
Parabolic integro-differential identification problems related to memory kernels with special symmetries
No full textWe are concerned with the problem of recovering the kernel k, depending on time and having a special spatial symmetry, in the parabolic integro-differential equation (1.1) and related to a domain which is union of level sets of each function k(t, ·). We single out a special class of differential operators A and two pieces of suitable additional information for which the problem of identifying k can be uniquely solved locally in time
Generation type inequalities for closed linear operators related to domains with conical points
No full textLet be a second-order linear differential operator in divergence form. We prove that the operator , where λ ∈ C and I stands for the identity operator, is closed and injective when Re λ is large enough and the domain of consists of a special class of weighted Sobolev function spaces related to conical open bounded sets of Rn, n ≥ 1
On the Behaviour of Singular Semigroups in Intermediate and Interpolation Spaces and Its Applications to Maximal Regularity for Degenerate Integro-Differential Evolution Equations
No full textFor those semigroups, which may have power type singularities and whose generators are abstract multivalued linear operators, we characterize the behaviour with respect to a certain set of intermediate and interpolation spaces. The obtained results are then applied to provide maximal time regularity for the solutions to a wide class of degenerate integro- and non-integro-differential evolution equations in Banach spaces
Fractional Powers and Interpolation Theory for Multivalued Linear Operators and Applications to Degenerate Differential Equations
No full textdepartmental bulletin pape
Plan de marketing para redistribuir los alimentos excedentes del sector HORECA y supermercados con el fin de destinarlo a las personas de bajos recursos y así reducir la contaminación ambiental proveniente de los residuos
No full textFil: Favaron, Josefina. Universidad de San Andrés. Escuela de Negocios; Argentina
- …
