Time lags in a “food-limited” population model. (English) Zbl 0639.34070
We obtain sufficient and necessary and sufficient conditions for the oscillation of all positive solutions of
\[
\dot N(t)=rN(t)(K-N(t- \tau))/(K+rcN(t-\tau)),
\]
where r,K,\(\tau\) \(\in (0,\infty)\) and \(c\in [0,\infty)\). We also obtain sufficient conditions for the global attractivity of the positive equilibrium K.
Reviewer: K.Gopalsamy
MSC:
| 34K99 | Functional-differential equations (including equations with delayed, advanced or state-dependent argument) |
| 92D25 | Population dynamics (general) |
| 34C10 | Oscillation theory, zeros, disconjugacy and comparison theory for ordinary differential equations |
Keywords:
global attractivityReferences:
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