In this paper new generalized notions are defined: -boundedness and -asymptotic equivalence, where is a complex continuous nonsingular matrix. The -asymptotic equivalence of linear differential systems and is proved when the fundamental matrix of is -bounded.
Asymptotic representations of some classes of solutions of nonautonomous ordinary differential -th order equations which somewhat are close to linear equations are established.
We provide a systematic study of boundary data maps, that is, 2 × 2 matrix-valued Dirichlet-to-Neumann and more generally, Robin-to-Robin maps, associated with one-dimensional Schrödinger operators on a compact interval [0, R] with separated boundary conditions at 0 and R. Most of our results are formulated in the non-self-adjoint context. Our principal results include explicit representations of these boundary data maps in terms of the resolvent...
This paper deals with the three-point boundary value problem for the nonlinear singularly perturbed second-order systems. Especially, we focus on an analysis of the solutions in the right endpoint of considered interval from an appearance of the boundary layer point of view. We use the method of lower and upper solutions combined with analysis of the integral equation associated with the class of nonlinear systems considered here.