Fan M, Wang K
Department of Mathematics, Northeast Normal University, People's Republic of China.
Math Biosci. 1998 Sep;152(2):165-77. doi: 10.1016/s0025-5564(98)10024-x.
In this paper, we examine the exploitation of single population modeled by time-dependent Logistic equation with periodic coefficients. First, it is shown that the time-dependent periodic Logistic equation has a unique positive periodic solution, which is globally asymptotically stable for positive solutions, and we obtain its explicit representation. Further, we choose the maximum annual-sustainable yield as the management objective, and investigate the optimal harvesting policies for constant harvest and periodic harvest. The optimal harvest effort that maximizes the annual-sustainable yield, the corresponding optimal population level, the corresponding harvesting time-spectrum, and the maximum annual-sustainable yield are determined, and their explicit expressions are obtained in terms of the intrinsic growth rate and the carrying capacity of the considered population. Our interesting and brief results generalize the classical results of Clark for a population described by the autonomous logistic equation in renewable resources management.
在本文中,我们研究了由具有周期系数的时变逻辑斯谛方程所建模的单种群开发问题。首先,证明了时变周期逻辑斯谛方程存在唯一的正周期解,该解对于正解是全局渐近稳定的,并且我们得到了它的显式表示。进一步地,我们选择最大年可持续产量作为管理目标,并研究了恒定收获和周期收获的最优收获策略。确定了使年可持续产量最大化的最优收获努力、相应的最优种群水平、相应的收获时间谱以及最大年可持续产量,并根据所考虑种群的内在增长率和环境容纳量得到了它们的显式表达式。我们有趣且简洁的结果推广了克拉克在可再生资源管理中针对由自治逻辑斯谛方程描述的种群的经典结果。