A method is proposed for synthesis of robust controllers based on PI and PID control laws for linear object with delay in the presence of parametric uncertainty of the inertial part and the uncertainty of setting the delay value. The method is based on robust Nyquist stability criterion and dynamic compensation technique. It is argued that the use of the proposed approach allows for a compromise between the rudeness of the control system and its performance.

An analysis of service disciplines with fixed and dynamic priorities is carried out. The object of study is an intermediate node of a multi-service network, where five data streams with different intensities and router service time arrive. Queuing system with a heterogeneous flow of applications is used as a model of such intermediate node. Studies of the heterogeneous queuing system with priorities are conducted by a statistical method in GPSS World simulation environment under the assumption of different laws for the distribution of time intervals between the queues arrivals and their processing time. Time dependences of the queue time on data stream number for different combinations of distribution laws with fixed and dynamic priorities are derived.

The use of the Kalman digital filter algorithm for parametric identification of differential-difference models of heat transfer in body systems by solving inverse problems of thermal conductivity is considered. The Kalman filter allows to estimate the uncertainty of recovery of the required parameters by minimizing the discrepancy between the measured and model values of the parameters, in particular, the unsteady heat flow. An analysis of the Kalman filter by parameters is given, its advantages and disadvantages are specified. An extended Kalman filter allowing to reduce significantly the volume of calculations of a matrix of sensitivity functions and to exclude completely need of a task of often unknown initial temperature distribution in object of research is proposed. The proposed method of recovery of non-stationary heat flow using the extended Kalman filter is implemented by the software complex "Heat Identification" and implemented in the practice of non-stationary thermometry. The results of model and full-scale experimental studies are presented.

Technological methods used for formation of the functional parameters, like moment of inertia and imbalance of cryogenic gyroscope rotor, are considered. As the material of the rotor, it was proposed to use a carbon-metal nanocomposite well combined in physical and chemical properties with niobium, but demonstrating a strong anisotropy of properties, which brings to the appearance of an imbalance. The performed research was aimed at revealing technical solutions for formation of moments of inertia and correction of imbalance caused by the anisotropy of the rotor substrate material. The proposed complex is a qualitatively new technological methods and means of manufacture of the rotor of a cryogenic gyroscope associated with the coordinated operations of the formation of the rotor workpiece of pyroboroncarbon and application of superconducting niobium coating. The developed technology was patented and used for the manufacture of an experimental rotor of a cryogenic gyroscope.

The distributed network of a cyber-physical production systems based on the private blockchain system Ethereum is considered. A description of the network structure and the interaction of network nodes through the execution of smart-contracts is given.

Problems arising in the small-scale production of two-stage float gyroscopes, are considered. Results of a study of variances as applied to these problems are presented. The experience in the use of dispersion analysis in the study of gyromotor rotors quality using MS Excel program is discussed. The influence of the human factor on the FD-factor of the adjusted device was investigated by means of one-factor analysis of variance. As a result, the hypothesis H1 about the presence of such influence is accepted, and the null hypothesis about the absence of the human factor influence on the integral estimation of the accuracy of the azimuthal gyroscope is confirmed. Results of the single-factor analysis of variance confirming the alternative hypothesis H1 on the significant effect of melting on the magnetic energy of the rotor blanks, are presented. The absence of the influence of difference in melting on the run-out time of the gyromotor in three orientations and on the values of consumption currents in the steady state mode is established. Two-factor analysis of variance is used in the study of the final FD-factor of the device. Results related to the effect on two independent variables — the human factor and the type of stator compound — are presented.

Results of studying the properties of the photo-catalytically active compositions SrBi4-уO7-z / ½у(BiO)2СО3, where y=1,2… 1,7, obtained by pyrolytic synthesis from organic precursor com-plexes of strontium and bismuth with sorbitol, are presented. The synthesized powder materials are shown to absorb light of the visible range up to 500 nm due to the presence of the narrow-band semiconductor SrBi4O7. The presence of the wide-band gap semiconductor (BiO)2СО3 provides effective separation of electron-hole pairs. The diffuse reflection spectra of the compositions differ from similar spectra of the mechanical mixture of these semiconductor phases of the same composition, which suggests the presence of a heterostructure in the semiconductor system. The catalytic particles synthesized at a temperature of 500 °C and containing 73 wt. % of SrBi4 уO7-z and 27 wt. % of (BiO)2СО3, have the greatest activity in me-thylene blue photo-decomposition. The possibility of controlling the optical properties and photocatalytic activity of the composition due to the joint formation of the phase of strontium bismuthate and the phase of bismuth oxycarbonate is demonstrated.

The effect of initial concentration of pollutant on the photocatalytic activity of photocatalysts based on calcium bismuthate is studied. This effect is investigated for photocatalysts of different composition and structure. The derived dependences allow to determine the optimal pollutant concentrations, as well as the photocatalyst composition and structure most promising for further practical use.

Results obtained by the conoscopic method in the study of LiNbO3: Zn crystals with a low photore-fraction effect in the concentration range of 4.46—7.5 mol. % ZnO are presented. Analysis of full-scale conoscopic patterns in the polarized laser radiation confirms the abrupt (threshold) nature of the effect of zinc on the optical properties of single crystals when the concentration changes. The maximum value of anomalous biaxiality angle of 2V = 24' and anomalous birefringence Δn = 0.557•10-5 are recorded for a sample of LiNbO3: Zn with concentration of 7.5 mol. %.

A model of two-layered multiferroic composite is applied to FeBO3-PZT structure. Forced oscilla-tions of domain boundaries in FeBO3 crystals in the field of elastic wave of various polarization are re-vealed with the use of magneto-optical Faraday effect for transmitted and reflected light. The dependence of the domain wall displacement on the voltage amplitude applied to the composite. The velocity and displacement of the domain boundary in the elastic wave field are estimated.

The possibility of using visualization of blood pulsations for studying processes of thermal relaxa-tion in human living tissues is investigated. The blood pulsation amplitude (BPA) in a tissue is experimentally demonstrated to depend on thermal effect on the tissue: cooling a tissue leads to a drop in BPA, and the process of heating a tissue is accompanied by its growth. The increase in the BPA rate is shown to be an individual characteristic of the subject, and therefore can serve as a parameter of vasomotor reactivity of vessels with temperature changes.

Actual problems of diagnosing the corrosion condition of hollow reinforced concrete structures are considered using reinforced concrete supports of the contact network as an example. Existing methods of diagnosing hollow reinforced concrete structures are discussed, advantages and disadvantages of these methods are revealed. The method of laser spectroscopy is reported to be the most promising approach to solving the problem due to its high reliability and the possibility to transmit laser radiation by fiber optic cable. A new design solution is proposed for positioning an optical probe inside a hollow structure to check the surface of the underground part of the reinforced concrete support. The optical probe is designed to determine the quantitative composition of corrosion products released to the surface of concrete by means of laser spectroscopy. A diagram of the optical sensor of the proposed device is presented, the sensor design is described. The proposed device allows to obtain quantitative information on the concentrations of corrosion products on the surface of reinforced concrete structure. Thus, by performing measurements on the surface and evaluating the condition of the reinforcement, it is possible to predict the residual strength of the supports, depending on the location of the point of greatest corrosion attack.

Results of automated measurements of the catalytic activity of bismuth coatings in the photodegradation reaction of an aqueous solution of a model pollutant are presented. The measurements were carried out with the help of a developed installation, in which the photoreaction and measurement cells are combined. Strontium bismuth nanosized powders synthesized by the pyrolytic method using sorbitol as an organic precursor, were deposited on a ceramic carrier as one-, four-, and seven-layer coatings. The effectiveness of photocatalytic coatings was assessed by the rate of decrease in the concentration of the organic methylene blue dye after prolonged irradiation by visible and ultraviolet light. The photocatalytic activity of strontium bismuthate-based coatings are shown to depend on the multiplicity of their deposition on the ceramic carrier. The high discreteness of the kinetic measurements revealed various stages of the photocatalytic process: sorption in the dark, photo-sorption, photocatalysis at a constant speed, the stage of slowing down the photocatalytic decomposition by reducing the concentration of methylene blue.

A new method for increasing the accuracy of measuring the difference in the thicknesses of two anisotropic plates using the Solc interference filter is proposed. Non-monochromatic radiation, after passing through the crossed Solc filter, has a periodic distribution of radiation intensity over wavelengths. The distance between neighboring radiation minima is proposed to be used for a rough estimate, and the study of polarization parameters of the radiation makes it possible to refine the obtained data. This method allows to determine a crystal plate thickness with an accuracy of 0.1 μm.

A fiber-optic accelerometer based on the Mach-Zehnder interferometer with an active working point stabilization system is developed. Results of field tests of the accelerometer, confirming the possibility of its use for monitoring of natural and man-made objects, are presented.