Periodicity in a food-limited population model with toxicants and state dependent delays

✍ Scribed by Fengde Chen; Dexian Sun; Jinlin Shi

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 192 KB
• Volume: 288
• Category: Article
• ISSN: 0022-247X
• DOI: 10.1016/s0022-247x(03)00586-9

✦ Synopsis

With the help of a continuation theorem based on Gaines and Mawhin's coincidence degree, easily verifiable criteria are established for the global existence of positive periodic solutions of a foodlimited population model with toxicant and state dependent delays, that is

,

where r(t), k(t), a(t), b j (t), d j (t), j = 1, 2, . . . , m, are continuous, real-valued periodic functions with period ω > 0 and r(t), k(t), a(t) > 0; b j (t), d j (t) 0, j = 1, 2, . . . , m, are periodic continuous functions with period ω > 0, τ j , η j are ω-periodic with respect to their first arguments. Some new results are obtained.