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An algorithm for the numerical propagation of acoustic waves in solids has been developed. The algorithm is based on the particles interaction model of in a tetrahedral crystal lattice. Numerical integration of Newton's equations in the calculation of particle trajectories is applied. The possibility of numerical modeling of wave diffraction processes on heterogeneities is shown. The resonant phenomena are observed in simulation of acoustic oscillations for an ultrasonic waveguide by means of proposed algorithm.

The experimental setup for ultrasonic controlled levitation in the air has been developed. Two phased arrays made of 91 ultrasonic radiators placed in front of each other are used. Arrays are focused in the region of particle levitation. The length of the focus area allows us to move the particles along it, controlling the standing waves through the phase difference of the two arrays.

Harmonic signal of a given frequency and amplitude is required for ultrasonic instrument operation.At a power output of 200 W there is a need to refine the scheme because of negative effects which could be neglected at lower power.This article shows an introduction of changes to the transformer switching circuit generating high power ultrasonic signal.

The characteristics of the ultrawideband (UWB) timed antenna array developed by the authors are described. The efficiency of the system is confirmed by experiments processed with the use of focusing and aperture synthesis methods. Technical solutions used in this work allow us to proceed to the development of the UWB radio tomograph operating in real time.

Article demonstrates possibility of monochromatic radiation usage for relief restoration. There is a problem with restoration when scanned object is not flat and it is not parallel to the scanning plane. It was discovered that two-dimensional phase distribution could be applied for distance determination. It is reliable way to solve problems listed above. In conclusion offered methods allow monochromatic microwave radiation usage for screening system development.

Within the limits of a linear model based on processing of data of direct calibration measurements with semiconductor multisensors, a method of their calibration by standard levels of gas concentration is substantiated for its subsequent application for small concentration levels. On an example of data for nitrogen dioxide, the notion of the normalized surface density of the gas is introduced, and its relationship with the volume concentration is established. On this basis, the feasibility of increase in the sensitivity and selectivity of the multisensor system by several orders of magnitude compared with the existing instrumental methods is substantiated by imitational modeling using mathematical methods of modern algebra and regularization theory.

Subsystems of the design of a complex security system for premises under conditions of large volume of passenger traffic are considered. These subsystems provide video- and thermal imaging control, radio wave tomography, and gas analysis. Simultaneous application of all examined variants will essentially increase the probability of timely prevention of dangerous situations with the probability of false alarm as low as possible. It is important that finally, this will provide protection of population and will facilitate the work of intelligence services.