On periodic-type solutions of systems of linear ordinary differential equations.
On perturbation of continuous maps
In [1], the concept of singular isolating neighborhoods for a continuous family of continuous maps was presented. The work was based on Conley's result for a continuous family of continuous flows (cf. [2]). In this note, we study a particular family of continuous maps to illustrate the results in [1].
On perturbation theory of a system of quasi-linear ordinary differential equations
On perturbations of deviations of periodic differential-difference equations in Banach spaces
On perturbed iterative linear differential equations of order .
On phases of accompanying spaces to a linear two-dimensional space of functions with a continuous first derivative
On plane polynomial vector fields and the Poincaré problem.
On point dissipative -dimensional systems of differential equations with quadratic nonlinearity.
On point-dissipative systems of differential equations with quadratic nonlinearity.
On Poisson-Dirichlet problems with polynomial data
In this note we provide a probabilistic proof that Poisson and/or Dirichlet problems in an ellipsoid in Rd, that have polynomial data, also have polynomial solutions. Our proofs use basic stochastic calculus. The existing proofs are based on famous lemma by E. Fisher which we do not use, and present a simple martingale proof of it as well.
On Pontryagin-Rodygin's theorem for convergence of solutions of slow and fast systems.
On Positive Entire Solutions of a Class of Second Order Semilinear Elliptic Systems.
On positive solutions for a nonlinear boundary value problem with impulse
In this paper we study nonlinear second order differential equations subject to separated linear boundary conditions and to linear impulse conditions. Sign properties of an associated Green’s function are investigated and existence results for positive solutions of the nonlinear boundary value problem with impulse are established. Upper and lower bounds for positive solutions are also given.
On positive solutions of a class of second order nonlinear differential equations on the halfline
The differential equation of the form , a ∈ (0,∞), is considered and solutions u with u(0) = 0 and (u(t))² + (u’(t))² > 0 on (0,∞) are studied. Theorems about existence, uniqueness, boundedness and dependence of solutions on a parameter are given.
On positive solutions of equations with two middle terms
On positive solutions of functional-differential equations in Banach spaces.
On positive solutions of nonlinear retarded differential equations
On positive solutions of semilinear elliptic problems
On practical stability and optimal stabilization of controlled motion
On products of non-commuting sectorial operators