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Abstract-The problem of object classification in seismic guard systems on the basis of statistical analysis of spectral moments used as features for classification is considered. An adaptive algorithm is developed, and its efficiency is experimentally determined.

An approach is proposed to increase the efficiency of nonparametric two-sample tests of scale by using a preliminarily grouping of initial observations by the level. The groups are formed using order statistics.

A solution was found to the problem of recognizing a spatial three-dimensional group point object with coordinate noise, a priori uncertainty of angular parameters, and a shift of the initial vector component that defines the object. An iterative approach to matching angular parameters and vector descriptions of the recognized and reference groups of point objects is proposed.

Correlations for the lower limit of the estimate error variance of images distorted by additive and applicative noise are obtained. The potential and actual estimate error variances for linear and nonlinear filtering algorithms are analyzed. A combined filtering algorithm for images distorted by applicative noise is developed.

A new method of abandoned object detection based on analyzing a sequence of depth images is proposed, and algorithms of real-time determination of the quasi-stationary background and abandoned objects are developed. The efficiency of the proposed algorithms is compared with that of the algorithm based on analyzing brightness images.

A method of solving two-dimensional limited-angle tomography problems, based on the Cavalieri condition for the Radon transform, is investigated. Two algorithms realizing this approach are compared between themselves and also with the algorithm calculating missing projections from approximate tomograms. Numerical simulations show that all three algorithms allow the reconstruction accuracy to be improved in the case under consideration. Each of them, however, has certain specific features, which should be taken into account in solving practical tasks.

The emergence and development of algorithms for three-dimensional reconstruction in X-ray tomography are considered in historical sequence. The data completeness condition for precise reconstruction of an object at one point is studied. It is shown that some precise algorithms are used to reconstruct part of the object from data satisfying the completeness condition for this part. Other algorithms for solving the same problem require a full set of data for the entire object.

The construction of a reliability function from the results of accelerated failure time (AFT) models is considered. The constructed AFT models are verified by analyzing a sample of residuals. The fit of the residual sample to the baseline probability distribution is tested using modified nonparametric goodness-of-fit tests. In the absence of censoring in tests, it is proposed to use previously constructed models of distribution of statistics for testing composite hypotheses. In the case of censoring of type I or II, distributions of the goodness-of-fit test statistics are found by statistical modeling.

The problem of stabilization of an unstable plant by a reduced-order single-channel controller is considered. The possibility of compensating small deviations of a double inverted pendulum on a cart by acting on the cart is studied. An algebraic method for finding the extreme locations of the poles through the construction of root simplexes is proposed. Using this, the Hurwitz stability boundaries for various reduced-order controllers are calculated. It is shown that robust stabilization of the pendulum system in the class of reduced-order controllers is impossible.

The basis sources and methods of reducing the errors of incremental photoelectric digital converters for angular measurements are analyzed. A method of constructing hybrid photoelectric converters that increase the accuracy of angular measurements is proposed. The result is achieved by simultaneous measurements of the turning angle and current radial deflections of the converter shaft axis.