Abstract
We offer sufficient and realistic criteria for the existence of positive periodic solutions for a class of non-autonomous scalar equations with deviating arguments. Both the continuous time case and the discrete time case are discussed. Our approach is based on the theory of coincidence degree and the related continuation theorem. To show the usefulness of the results obtained, we include applications to several famous population models.
Acknowledgements
The authors thank the referees for their many thoughtful suggestions that led to an improved exposition of the manuscript. Meng Fan was supported by the NNSF of P. R. China (Nos. 10171010 and 10201005), the Key Project on Science and Technology of the Education Ministry of P. R. China (Nos. Key 01061) and the Science Foundation of Jilin Province of P. R. China for Distinguished Young Scholars.
Notes
Correspondence to: Meng Fan, e-mail: [email protected]