Optimal control of population dynamic system with age-structure in periodic environment;

Optimal Harvesting for Time-varying Population Dynamics with Spatial Diffusion and Age-structure;

The existence and uniqueness of nonnegative solutions of an age-structured MSEIR epidemic model with vaccination;

Change of age structure of population and its relationship to develop ment of health business in Henan province;

The changes of the catch and age structure of lake anchovy and the relationship with environmental variation in Lake Taihu;

Age estimation and age structure of Cycas fairylakea population in Shenzhen City;

Asymptotic behavior of a nonlinear infection-age-dependentepidemic model;

Non-linear age-dependent population models;

This paper is mainly concerned with optimal harvesting policy for three competing species with age-dependent and diffusion.

The Stability of a Diffusive Predator-prey Model with Stage-structure;

This paper studied a two-species delayed stage-structured competitive model.

The stability of the positive constant solution of the competitive model with stage-structure and diffusion under Neumann boundary condition is discussed.

It also shows low unit stock volume,unreasonable forest age structure,low forestland use ratio and severe pest,disease and rat disaster.

Based on the analysis of the current management of the forests on Saihanba Tree Farm, and on the theory of classified management, countermeasures for forest sustainable development as regulating forest species structure and current forest age structure, regenerating tree species, preventing forest fire, resolving the countradiction of forestry with hushandry, etc, are put forward in this paper.