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This paper presents the results of experimental studies and numerical calculations of weather-dependent ecological risks to social infrastructure facilities from the effects of powerful infrasonic vibrations generated by man-made and natural explosions. The results were obtained by applying an original ecologically safe approach developed by the authors and involving the use of seismic vibrators as sources simulating explosions but having much less power compared to the explosions. Such sources generate both seismic and acoustic (seismoacoustic) vibrations with precision metrological power and frequency-time characteristics, which, in contrast to explosions, ensures high reproducibility of research results. Results comparable to explosions are achieved due to the energy accumulation of weak vibroseismoacoustic signals. The propagation of infralow-frequency wave fields is studied depending on weather conditions and taking into account the effect of heterogeneity of the atmosphere. The results of the experiments are compared with those of numerical calculations.

Synthesis methods based on spatial-frequency filtering have been developed for fractal images for which the structure functions are power laws over a wide range of increments which is about one-quarter of the image size. It is shown that, using theWeierstrass function, only stationary processes (images) can be simulated. An algorithm for modeling fractional Brownian images is proposed and studied. It is established that the integral characteristic of the spectrum of a Brownian image with the Hurst parameter α is well approximated by a power function with an exponent 2(α + 1) for α ∈ (0, 1/2] and an exponent of 3 for α ∈ (1/2, 1). Using as an examples modifications of images of samples of amorphous alloys, it is shown that statistically self-similarity images little different from the original image can be simulated. This allows one to determine to what extent the structures visualized in the images exhibit fractal properties.

Well-known and original methods of spectral filtering of the seismic noise occurring in hydraulic fracturing have been studied and applied. They allow control of artificial noise and natural interference due to the nonlinear propagation of seismic signals and the resonance properties of the reservoir rock. Original spatial filtering is applied to eliminate the redundancy of location data. A threedimensional model for the reservoir fracture zone formed by hydraulic fracturing is proposed.

An approach is proposed to design transfer functions with prescribed direct measures of transient performance: overshoot and setting time. A technique for designing such functions is developed. A numerical example is given.

Digital identification and evaluation of the kinetics of damage accumulation on the surface of a fatigue sensor are performed using digital image processing. Damage accumulation is evaluated from the results of diagnosis of individual stages of cyclic deformation. It is found that the different stages of damage correspond to particular image parameters. The main features in the development of shear processes were identified by consistent processing of surface damage data. Theoretical background and experimental results are presented.

One way to increase the reliable and robust operation of large-scale computing systems is to introduce a reserve (a structural redundancy system) to them. A model for the analysis of the operation of distributed computing systems is proposed. The results of analytical and simulation modeling are presented. Flows of events with a Weibull distribution (shape parameter values of 1 and 0.78) are considered.

Results of computational experiments aimed at studying the accuracy characteristics of interchannel gradient reconstruction of signals of color digital images distorted by impulse noise with different brightness distribution laws, which are not correlated between the channels, are generalized. Examples of interchannel reconstruction of color digital images on the basis of different sets of gradient estimates are presented.

A signal processing algorithm for a passive seismic monitoring system is proposed and experimentally verified. This algorithm ensures effective detection and determination of the trajectory of a moving object. A concentrated receiver consisting of two geophones separated by a distance much smaller than the detected signal wavelength is used in experiments. Processing of experimental results shows that it is possible to determine not only the position of the seismically active object, but also the parameters of its motion.

A new method of decomposition of the interval of the values of random variables based on results of optimization of the nonparametric estimate of the probability density of the Rosenblatt-Parzen type is proposed. Its application in the problem of testing the hypothesis of identity of the distribution laws of two sequences of one-dimensional random variables is considered.

Various approaches to estimation and suppression of a motionless background with the use of texture correlations in the problem of detection of small-size dynamic targets are considered. Algorithms of suppression of a locally flat background, background suppression by means of bilateral filtration, and an algorithm of background estimation and suppression with the use of an autocorrelation function are implemented. For anisotropic textures with boundary transitions, an algorithm of background estimation and suppression along the boundary and an algorithm of three-channel filtration are proposed and implemented. Operation of these algorithms on textures representing different classes of images is compared. It is demonstrated that the algorithm with background estimation along the boundaries yields good results for model data with a large number of linear boundaries, but its operation on mixed-type textures is less efficient than that of other available approaches. Among the considered algorithms, the approach based on three-channel filtration ensures the greatest increase in the signal/noise ratio for various textures modeling real images.