Diffusive logistic equations with indefinite weights: population models in disrupted environments

RS Cantrell, C Cosner - Proceedings of the Royal Society of …, 1989 - cambridge.org
The dynamics of a population inhabiting a strongly heterogeneous environment are
modelledby diffusive logistic equations of the form ut= d Δu+[m (x)—cu] u in Ω×(0,∞), where …

Fractal drum, inverse spectral problems for elliptic operators and a partial resolution of the Weyl-Berry conjecture

ML Lapidus - Transactions of the American Mathematical Society, 1991 - ams.org
Let $\Omega $ be a bounded open set of ${\mathbb {R}^ n}\;(n\geq 1) $ with" fractal"
boundary $\Gamma $. We extend Hermann Weyl's classical theorem by establishing a …

Eigenvalue branches of the Schrödinger operatorH−λW in a gap of σ(H)

S Alama, PA Deift, R Hempel - Communications in Mathematical physics, 1989 - Springer
Eigenvalue branches of the Schr&#x00F6;dinger operator <Emphasis Type="Italic">H </Emphasis>&#x221
Page 1 Commun. Math. Phys. 121,291-321 (1989) Communications in Mathematical Physics …

Weyl's formula for a class of pseudodifferential operators with negative order on L2(Rn)

M Dauge, D Robert - Pseudo-Differential Operators: Proceedings of a …, 1987 - Springer
Introduction The startmg point of this work is a paper by Birman and Solomjak [BI-SO I] m
which they study the eigenvalues asyrnptotics of a class of integral compact operators on V …

Principal eigenvalues for problems with indefinite weight function on 𝑅ⁿ

KJ Brown, C Cosner, J Fleckinger - Proceedings of the American …, 1990 - ams.org
We investigate the existence of positive principal eigenvalues of the problem $-\Delta u
(x)=\lambda g (x) u $ for $ x\in {R^ n}; u (x)\to 0$ as $ x\to\infty $ where the weight function …

Stochastic convergence of regularized solutions and their finite element approximations to inverse source problems

Z Chen, W Zhang, J Zou - SIAM Journal on Numerical Analysis, 2022 - SIAM
In this work, we investigate the regularized solutions and their finite element solutions to the
inverse source problems governed by partial differential equations, and we establish the …

[图书][B] Elliptic Boundary Value Problems with Indefinite Weights, Variational Formulations of the Principal Eigenvalue, and Applications

F Belgacem - 1997 - books.google.com
Elliptic Boundary Value Problems With Indefinite Weights presents a unified approach to the
methodologies dealing with eigenvalue problems involving indefinite weights. The principal …

Eigencurves for two-parameter Sturm-Liouville equations

P Binding, H Volkmer - SIAM review, 1996 - SIAM
This paper concerns two-parameter Sturm-Liouville problems of the form -
(p(x)y')'+q(x)y=(λr(x)+μ)y,\quada\leqslantx\leqslantb with self-adjoint boundary conditions at …

Two-dimensional Maxwell's equations with sign-changing coefficients

ASBB Dhia, L Chesnel, P Ciarlet Jr - Applied Numerical Mathematics, 2014 - Elsevier
We consider the theoretical study of time harmonic Maxwell's equations in presence of sign-
changing coefficients, in a two-dimensional configuration. Classically, the problems for both …

Convex relaxations of integral variational problems: pointwise dual relaxation and sum-of-squares optimization

A Chernyavsky, JJ Bramburger, G Fantuzzi… - SIAM Journal on …, 2023 - SIAM
We present a method for finding lower bounds on the global infima of integral variational
problems, wherein is minimized over functions satisfying given equality or inequality …