Periodic Solutions in a Delayed Competitive System with the Effect of Toxic Substances on Time Scales

In this paper, the existence of periodic solutions of a delayed competitive system with the effect of toxic substances is investigated by using the Gaines and Mawhin,s continuation theorem of coincidence degree theory on time scales. New sufficient conditions are obtained for the existence of periodic solutions. The approach is unified to provide the existence of the desired solutions for the continuous differential equations and discrete difference equations. Moreover, The approach has been widely applied to study existence of periodic solutions in differential equations and difference equations.

• Changjin Xu
• Qianhong Zhang

• Time scales
• competitive system
• periodic solution
• coincidence degree
• topological degree.

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