Considering the population evolution process of a community with a large population, suppose F(r, t) denotes the number of individuals aged less than r at the time t, p(r, t)=(?)F(r, t)/(?)r the age distribution or th...Considering the population evolution process of a community with a large population, suppose F(r, t) denotes the number of individuals aged less than r at the time t, p(r, t)=(?)F(r, t)/(?)r the age distribution or the state of the population. The evolution of the population state satisfies the following differential equation:展开更多
文摘Considering the population evolution process of a community with a large population, suppose F(r, t) denotes the number of individuals aged less than r at the time t, p(r, t)=(?)F(r, t)/(?)r the age distribution or the state of the population. The evolution of the population state satisfies the following differential equation:
