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A system of transformations of the initial process with nonstationary season variations is considered. The process is described by an autoregressive multiplicative model and an integrated moving average for further forecasting. The transformations are completed by reducing the initial process to a stationary form to realize model identification and forecast the process.

Implementation of an automatic process control system for the Severomuiskii tunnel is presented. Its subsystems are considered, which can be used for design of other similar control systems.

An algorithm for estimating the parameters and correcting the geometric distortions for the unknown focal length is obtained. A relationship between the directional field and the values of geometric distortion parameters is found. The relationship makes it possible to transform straight scratch images into horizontal lines. Results of experimental investigation are presented. They prove the possibility of using the directional field for solving the problem of correcting the geometric distortions of images obtained in track or ballistic investigations.

Measuring crystal diameters during Czochralski growth is investigated. An image of the crystallization meniscus zone is analyzed. Informative parameters are determined for finding crystal diameters. An algorithm for calculating the diameter of meniscus applied for crystal growth control is described. Results on operation of a sensor using the algorithm during real crystal growth are presented.

Applying the ant colony algorithm for solving the problem of parametric fuzzy model identification is presented. Transition from continuous optimization to discrete one via constructing a complete oriented decision-search graph is determined. A gradient algorithm is considered as the second optimization step. Experiments for analyzing the performance of the algorithms for optimization and fuzzy system are described.

The algorithm for reconstructing a 2D input signal (the image measured) by a finite realization of a 2D signal at the digital optical recording system output with the use of the fast Fourier transform is analyzed. The image reconstruction error is estimated.

Reconstructing the phase distribution of scalar speckle fields arising under light-induced scattering in a photorefractive  crystal is considered. A phase distribution reconstruction method based on simultaneous processing of two interferograms obtained for orthogonal planes of converging reference and signal beams is proposed. The method is more advantageous than single-interferogram methods for analyzing interferograms in the frequency domain because it enables to reduce the number of false-detected optical vortices and increase the SNR in phase reconstruction.

A method for physical process approximation using the differential Taylor transformation is substantiated. The power basis is transformed to bases of orthogonal Chebyshev polynomials. It is shown that the convergence of series is substantially increased by transition to expansion in Chebyshev polynomials of first kind and shifted Chebyshev polynomials. An algorithm for calculating differential spectrum discretes is formulated. It is observed that in the Chebyshev bases, the value of spectrum discretes decreases constantly as their number grows. In this case, it is possible to stop computing the discretes as they achieve the required small value, but this cannot be done in the power basis. Numerical examples illustrate the advantage of the proposed approach.

The average and maximum number of positive overshoots of the multiparticle Doppler signal envelope for the given threshold and also the average durations of positive and negative overshoots as a function of threshold are found. It is shown that the average duration of the positive envelope overshoots is inversely proportional and the average duration of the negative overshoots is proportional to the relative threshold. A tradeoff threshold value that ensures the required measurement accuracy for an admissible level of signal information loss is found.

Publications concerned with investigation and synthesis of switched systems are reviewed. Frequently used mathematical models of the systems are presented. Attention is focused on the problem of system stability for arbitrary and limited switching signals. Relationship between switched and fuzzy systems is illustrated. Some approaches to synthesizing switched controllers and state observers are considered.