Electronic Journal of Differential Equations,
Vol. 2007(2007), No. 149, pp. 1-12.

Title: Two classical periodic problems on time scales

Authors: Pablo Amster    (Univ. de Buenos Aires, Argentina)
         Christopher C. Tisdell (The Univ. of New South Wales, Australia)

Abstract: 
 We consider the generalization of two classical
 periodic problems to the context of time scales.
 On the one hand, we generalize a celebrated result by Castro
 for the forced pendulum equation. On the other hand, we
 extend a well-known result by Nirenberg to a resonant
 system of equations on time scales.  Furthermore, the results are
 new even for  classical difference equations.
 
Submitted April 3, 2007. Published November 09, 2007.
Math Subject Classifications: 39A12, 39A99.
Key Words: Time scale; boundary value problem; forced pendulum equation;
           Landesman-Lazer conditions; existence of solutions.