In this manuscript, we study the inverse problem for non self-adjoint Sturm--Liouville operator $-D^2+q$ with eigenparameter dependent boundary and discontinuity conditions inside a finite closed interval. By defining  a new Hilbert space and  using its spectral data of a kind, it is shown that the potential function can be uniquely determined by part of a set of values of eigenfunctions at som...

We consider the Euler system of compressible and entropic gaz dynamics in a bounded open domain of R with wall boundary condition. We prove the existence and the stability of families of solutions which correspond to a ground state plus a large entropy boundary layer. The ground state is a solution of the Euler system which satisfies some explicit additional conditions on the boundary. These co...

An overlapping Schwarz domain decomposition is applied to a semilinear reaction-diffusion equation posed in a smooth two-dimensional domain. The problem may exhibit multiple solutions; its diffusion parameter ε2 is arbitrarily small, which induces boundary layers. The Schwarz method invokes a boundary-layer subdomain and an interior subdomain, the narrow subdomain overlap being of width O(ε| ln...

in this paper, dynamic analysis of the composite truncated sandwich conical shells (stcs) with various boundary conditions subjected to low velocity impact was studied analytically, based on higher order sandwich panel theory. impact was assumed to occur normally over to the top face-sheet and the contact force history is predicted using two solution models of the motion are derived based on ha...

we introduce a rbfs mesheless method of lines that decomposes the interior and boundary centers to obtain the numerical solution of the time dependent pdes. then, the method is applied with an adaptive algorithm to obtain the numerical solution of one dimensional problem. we show that in the problems in which the solutions contain region with rapid variation, the adaptive rbfs methods are succe...

The numerical analysis of boundary layer effect is one of the major concerned problems in boundary element method (BEM). The accuracy of this problem depends on the precision of the evaluation of the nearly singular integrals. In the boundary element analysis with direct formulation, the hyper-singular integral will arise from the potential derivative boundary integral equations (BIEs). Thus th...

Abstract This work presents a review and analysis of modern asymptotic methods for singularly perturbed problems with interior boundary layers. The central part the is author his colleagues disciples. It highlights initial-boundary value nonlinear elliptic parabolic partial differential equations, as well periodic problems, which are widely used in applications called reaction–diffusion reactio...

We propose an extension of the discontinuous Galerkin local orthogonal decomposition multiscale method, presented in [14], to convection-diffusion problems with rough, heterogeneous, and highly varying coefficients. The properties of the multiscale method and the discontinuous Galerkin method allows us to better cope with multiscale features as well as interior/boundary layers in the solution. ...

This paper studies and analyzes a preconditioned Krylov solver for Helmholtz problems that are formulated with absorbing boundary layers based on complex coordinate stretching. The preconditioner problem is a Helmholtz problem where not only the coordinates in the absorbing layer have an imaginary part, but also the coordinates in the interior region. This results into a preconditioner problem ...