摘要
This paper discusses the most general time-varying population system, proves the necessary and sufficient conditions for systems to be stable in the sense of Lyapunov, and obtains the critical fertility rates β_(cr)(t) and β_(cr) of females for the system related to the stability for the system. And the explicit analytic expressions for the state ot the system are deduced. These results can provide a strict theoretical datum for the decision ot population policies.
This paper discusses the most general time-varying population system, proves the necessary and sufficient conditions for systems to be stable in the sense of Lyapunov, and obtains the critical fertility rates β<sub>cr</sub>（t） and β<sub>cr</sub> of females for the system related to the stability for the system. And the explicit analytic expressions for the state ot the system are deduced. These results can provide a strict theoretical datum for the decision ot population policies.
基金
Project supported by the National Natural Science Foundation of China
