Several phenomena analysed in both natural and social sciences models require the use of systems including current variables and lagged variables. The interest in retarded ordinary or partial differential equations has gained much attention recently because it has been seen that the introduction of time delays allows the capturing of more complex dynamics, thus enriching the description of the whole system. This special issue collects several manuscripts from people who work in different research fields. In total there were seventy-three submissions and only twenty-three were accepted for publication. The topics of the accepted papers range from theoretical studies to applications. In particular, there are new theoretical results on stochastics and fuzzy time delayed dynamic systems, on global stability, and on delay partial differential equations. With regard to the articles that focused on specific models, we mention here some interesting applications on disease dynamics, economic growth and business cycles, population dynamics, ecological systems, neural networks, and physics problems.
Acknowledgments
The guest editors would like to express their gratitude to all the authors and reviewers who took part in the success of this special issue.
Luca Guerrini
Luca Gori
Akio Matsumoto
Mauro Sodini
Zizhen Zhang
Carlo Bianca