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Permanence for Nicholson-type delay systems with nonlinear density-dependent mortality terms. (English) Zbl 1232.34109
Sufficient conditions are obtained for permanence of the following system $$ x^{'}_1(t)=-D_{11}(t,x_1(t))+D_{12}(t,x_2(t)) +c_1(t)x_1(t-\tau_1(t))e^{-\gamma_1(t)x_1(t-\tau_1(t))},$$ $$ x^{'}_2(t)=-D_{22}(t,x_2(t))+D_{21}(t,x_1(t)) +c_2(t)x_2(t-\tau_2(t))e^{-\gamma_2(t)x_2(t-\tau_2(t))}.$$

34K60Qualitative investigation and simulation of models
92D25Population dynamics (general)
34K25Asymptotic theory of functional-differential equations
Full Text: DOI
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[5] Berezansky, L.; Braverman, E.; Idels, L.: Nicholson’s blowflies differential equations revisited: Main results and open problems, Applied mathematical modelling 34, 1405-1417 (2010) · Zbl 1193.34149 · doi:10.1016/j.apm.2009.08.027
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