Parameter Identification Of A Class Of Nonlinear Biological Systems

In this article,we take the cultivation of algae to produce Carotenoids as the background,we consider a class of nonlinear dynamic systems and the parameter identification of such systems.The main content of this article are summarized as follows:1: The properties of the non-linear dynamical system of microalgae cultivation are discussed,and the existence,uniqueness,and continuous dependence of the solution on initial values and parameters of the system are proved.2: Based on the nonlinear dynamic system,we take the average relative error between the experimental data and the calculated value under different light intensities as the objective function,and the allowable range of cell concentration and product concentration are established as linear inequality constraints,parameters to be identified as the control variable to establish the identification model of the parameter variable,and prove the existence of the solution of the problem.Considering the problem that the particle swarm algorithm is easy to be premature,this article gives a certain amount of disturbance to the parameter,and analyzes the sensitivity of the parameter.On this basis,an adaptive particle swarm optimization algorithm based on parameter sensitivity analysis is constructed to solve the identification problem.3:Then we use the above algorithm to solve the parameter identification problem of the non-linear system of microalgae cultivation and the parameter identification problem of enzymecatalyzed batch fermentation.The numerical results show that the proposed algorithm is effective and can obtain the best parameters which can fit the experimental data.