articles

We have proposed a method for constructing dynamically redefined structures for the purpose of modeling abrupt changes in biological processes. The method provides for the analysis of scenarios with a control action, which is aimed at optimizing the profit from the exploitation of biological resources. The situations are described by three differential equations, which are numerically solved on adjacent time intervals. The state of the predicate set controls the selection of dynamically overridden coefficients. We carry out comparisons of all predicates on the basis of averaged individual indicators of generations. Threshold states in the dynamics of population size are a consequence of the selection of events as special nonequilibrium states that change the regulation algorithm. Our method makes it possible to implement dangerous qualitative changes in the scenarios of biological resource management, when the stable modes of their existence are suddenly lost. For practical problems, we have algorithmically implemented computational scenarios for two different processes such as the collapse of fish stocks under expert control of the fishery and a rapid outbreak of pests. The situation of the collapse of the fish population in the scenario with control develops in two stages and is a consequence of the experts 'desire to optimize the operation with uncertainty in an expert’s assessment of a state of a fishery. To confirm the relevance of our models, comparisons are made with the graphs of the development of the two real processes, as the spontaneous population explosion and the stock crisis during optimization of the sea cod fishery.