Acta mathematica scientia,Series A ›› 2016, Vol. 36 ›› Issue (3): 584-600.

Previous Articles    

A Weighted Population Model with Size-Structure: Stability and Optimal Harvesting

He Zerong, Yang Lizhi   

  1. Institute of Operational Research and Cybernetics, Hangzhou Dianzi University, Hangzhou 310018
  • Received:2015-10-11 Revised:2016-03-23 Online:2016-06-26 Published:2016-06-26
  • Supported by:

    Supported by the NSFC (10771048, 11271104)

Abstract:

This paper is concerned with the stability and optimal harvesting for a size-structured population model with control of newborns, where fertility and mortality depend the density in different ways. A formal equilibrium is derived and existence of unique steady state is shown via a contraction mapping. Some conditions for asymptotical stability and instability are presented by means of characteristic equation. As for the optimal harvesting problem, we cite the tangent-normal cones to establish an optimal feedback policy, and employ the Ekeland's variational principle to prove the existence and uniqueness of optimal strategies. Two examples demonstrate the evolution of the species.

Key words: Size-structure, Population model, Stability, Optimal control, Normal cone, Ekeland's variational principle

CLC Number: 

  • O211.4
Trendmd