Informatica

The new nonlocal delayed feedback controller is used to control the production of drugs in a simple bioreactor. This bioreactor is based on the enzymatic conversion of substrate into the required product. The dynamics of this device is described by a system of two nonstationary nonlinear diffusion-reaction equations. The control loop defines the changes of the substrate concentration delivered into the bioreactor at the external boundary of the bioreactor depending on the difference of measurements of the produced drug delivered into the body and the flux of the drug prescribed by a doctor in accordance with the therapeutic protocol. The system of PDEs is solved by using the finite difference method, the control loop parameters are defined from the analysis of stationary linearized equations. The stability of the algorithm for the inverse boundary condition is investigated. Results of computational experiments are presented and analysed.

This paper discusses the linear periodically time‐varying (LPTV) system parameter estimation using a block approach. An block algorithm is proposed for optimal estimation of the parameters of LPTV system from the input sequence and the output sequence corrupted by additive Gaussianly distributed noise. In the proposed method, the least squares error criterion has been used.The algorithm provides a useful computational tool based on an appropriate theoretical foundation for parameter estimation of linear time‐invariant (LTI) systems from input and output data. Simulation results are presented that demonstrate the performance of the approach.

This paper is devoted to the investigation of the investigation of the convergence of iterative methods for solving boundary value problems with discontinuous coefficients. The dependence of the rate of convergence on the size of the discontinuity of coefficients is analyzed for three popular general iterative methods. A new criterion on the applicability of such methods is proposed and investigated. The efficiency of this criterion is demonstrated for a model problem.

This paper is devoted to the application of adaptable difference schemes for the simulation of propagation and interaction of focused laser beams. New effective processes for the solution of stationary nonlinear optics problems are proposed. Simulation results on real experiment data show the advantages of such schemes and iteration processes.