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Distributed computing systems functioning in regimes of processing a parallel task packet with variable parameters is considered. Heuristic algorithms for distributing task packets on elementary machines of a computing system, which minimize the time or penalty for solution delay, are proposed. Modeling results confirming that the algorithms ensure at least subminimal values of criterion functions are listed.

For classifying stable processes of autoregression with random coefficients and Gaussian noise, it is proposed to use a sequential procedure with a guaranteed probability of right decision. The lower bound for the probability of right classification and an asymptotic formula for mean procedure duration are obtained. Asymptotic normality of statistics used for classification is proved. Results of numerical modeling are presented.

A new slice-by-slice reconstruction algorithm based on the Fourier synthesis method is proposed for projection geometry with a source moving along a circle. The time estimate of reconstructing by this algorithm on an N x N x N grid from M projections is O(MN²log₂N). The estimate is O(N / log₂N) times less than that for classical implementation of Feldkamp algorithm. A computational experiment showed that the Feldkamp algorithm yields in accuracy to the method of Fourier slice-by-slice synthesis in the case of a small radius of the source movement circle (3

New approaches to designing highly accurate laser Doppler measurement systems (LDMS) are presented. They are based on the concept of instantaneous frequency of the analytical Doppler signal, the algorithms of its maximum likelihood estimates, and the principles of tracking filtering. LDMS based on those principles is described and results of its metrological investigation and applications in an aerodynamic experiment are presented. The adopted engineering solutions are presented and substantiated.

A new algorithm synthesis approach based on evolutionary computation, templates and skeletons of algorithms, and a given set of pairs of input-output data is described. An evolutionary synthesis algorithm combining advantages of genetic algorithms and genetic programming, and used for automation of discovery and synthesis of some computational and combinatorial algorithms is presented.

A new method of identifying parameters for a high-speed adaptive system suppressing torque ripples in a permanent magnet synchronous motor is proposed. Simulation confirmed the high rate of convergence of the sought field parameters to the actual values.

Algorithms for synchronous motor excitation voltage control are proposed. They ensure control of the reactive power and suppress of rotor swings as the terminal voltage and the load torque fluctuate. The algorithms are based on estimating the internal rotor angle and on organizing the forced sliding movement of the system in the desired trajectory. The control algorithms are implemented in a fuzzy controller.

The second-order variable structure system with the non-ideal switching device is analyzed during its motion in the switching mode. A definition of this mode is given. Conditions of its existence and stability, and also conditions of falling the representative point into the switching area are obtained. The property of variable structure system robustness in the switching mode is formulated and proved. The maximum estimate of the system working accuracy compared with the ideal sliding mode is obtained. A method for reducing the auto-oscillation amplitude is developed.

The problem of synthesizing extremum control systems for the class of plants with a nonlinear time-varying dynamic part and a static quality function is discussed. It is proposed to organize two-contour control when the internal subsystem includes a dynamic plant part and the external subsystem contains a static extremum characteristic. The internal contour uses a controller based on the localization method. This makes it possible to preliminary stabilize the processes in the dynamic part of the system, and while synthesizing the external contour to take into account only the equilibrium value of the internal contour. Application of adequate gradient estimation along with the integral control law for the external subsystem allows organization of motion to extremum with the given dynamic quality. It is shown that the properties of such extremum control systems do not depend on the effect of the time-varying plant parameters and the action of uncontrolled external disturbances.

Adaptive stabilization of SISO systems with essentially nonstationary dynamic charac- teristics is discussed. Systems with parametric and (or) additive limited disturbances are considered. The adaptive algorithm design is based on the localization principle. It is proposed to reduce the system order due to decreasing the number of adjustable coefficients of the controller. Stability conditions for these systems are obtained.