Almost periodic and quasi-periodic solutions of differential equations

Almost Periodic Solutions of Second Order Nonlinear Differential Equations with Almost Periodic Forcing

Ergodicity and Asymptotically Almost Periodic Solutions of Some Differential Equations

Using ergodicity of functions, we prove the existence and uniqueness of (asymptotically) almost periodic solution for some nonlinear differential equations. As a consequence, we generalize a Massera’s result. A counterexample is given to show that the ergodic condition cannot be dropped. 2000 Mathematics Subject Classification. Primary 34C27, 43A60, 37Axx, 28Dxx.

Asymptotic equivalence of differential equations and asymptotically almost periodic solutions

In this paper we establish asymptotic (biasymptotic) equivalence between spaces of solutions of a given linear homogeneous system and a perturbed system. The perturbations are of either linear or weakly linear characters. Existence of a homeomorphism between subspaces of almost periodic and asymptotically (biasymptotically) almost periodic solutions is also obtained.

Perturbing Almost Periodic Differential Equations

ABSTRACT. When the zero solution of an almost periodic differential system is uniform-asymptotically stable, it is shown that the zero solution is diminishingly asymptotically stable and totally asymptotically stable. Generalization of the above theorem to bounded solutions and functional differential equations with finite time-lag are obtained by the same method. The techniques used in the pro...

On Almost Periodic Differential Equations

The notion of an invariant set has been widely exploited in the theory of autonomous ordinary differential equations. The purpose of this announcement is to give a natural and useful generalization of invariant sets to almost periodic systems. The proofs and several applications and extensions of our results will appear elsewhere. We consider systems of n first order, almost periodic, ordinary ...