We investigate two boundary value problems for the second order differential equation with -Laplacian where , are continuous positive functions on . We give necessary and sufficient conditions which guarantee the existence of a unique (or at least one) positive solution, satisfying one of the following two boundary conditions:
In the paper it is shown that each solution ot the initial value problem (2), (3) has a finite limit for , and an asymptotic formula for the nontrivial solution tending to 0 is given. Further, the existence of such a solutions is established by examining the number of zeros of two different solutions , .
We consider a neutral type operator differential inclusion and apply the topological degree theory for condensing multivalued maps to justify the question of existence of its periodic solution. By using the averaging method, we apply the abstract result to an inclusion with a small parameter. As example, we consider a delay control system with the distributed control.
M. Hirsch's famous theorem on strongly monotone flows generated by autonomous systems u'(t) = f(u(t)) is generalized to the case where f depends also on t, satisfies Carathéodory hypotheses and is only locally Lipschitz continuous in u. The main result is a corresponding Comparison Theorem, where f(t,u) is quasimonotone increasing in u; it describes precisely for which components equality or strict inequality holds.