A large number of power receivers with non-linear current-voltage characteristics with a pulsed mode of operation appeared in residential buildings, which leads to the generation of 0.38 kV higher harmonic current components into the electric network, large values ​​of these harmonics lead to a deterioration in the shape of the network voltage curve. The purpose of the work is to study the harmonics of current generated by electrical receivers of residential buildings, and their influence on the coefficient of non-sinusoidality of the network voltage of 0.38 kV. It has been established that the greatest negative impact on the electric network is exerted by electronic devices with switching power supplies, such as PCs, laptops and netbooks, as well as dishwashers and LED lamps with a socle E14 and E27, whose total harmonic current component coefficient is 85% ≤ THDI ≤ 205%. In the Matlab Simulink program, a simulation model of a 0.38 kV network of a residential building is simulated, which allows the study of the total distortion coefficient of the current KI and voltage KU in the ASU. With the installed non-linear load power more than double the linear load, the coefficient of non-sinusoidality of the voltage in the network of 0.38 kV may exceed the values ​​established by GOST 32144-2013.

Keywords: power supply system, electric network, quality of electric energy, voltage harmonics, current harmonics, electromagnetic compatibility, power receiver

This article focuses on solving the urgent task of forecasting hazardous mining zones by determining the position of local centers of tension in a processed coal seam. The relevance of this task is confirmed by the fact that the intensification of mining processes inevitably leads to an increase in the risk of hazardous production situations, such as rock blows, sudden coal and rock emissions, etc. The most dangerous for the manifestation of rock strikes are the protrusions of the edge sections of the coal seam, intersection and pairing workings. Shockproof activities regulated by the normative documents, are not always sufficiently effective. To solve this problem, authors propose an approach that allows you to quickly determine the position of local centers of tension, taking into account the influence of the worked out space. The authors developed an integration grid, in the construction of which the division of the entire area into elementary sections is performed in such a way that the influence of the weight of the roof rocks over each section is the same. To implement this approach, the influence function of the worked out space is introduced in the form of the equation of the reference rock pressure diagram. Based on the results of numerical simulation of the stress-strain state of the geomassiv, an exponential dependence is obtained, which allows one to determine the concentration coefficient of vertical stresses for points on the plot of reference rock pressure. According to the values of vertical stresses calculated for each point of the integration grid, it is possible to predict the stress-strain state of the geomassiv and justify the need for shockproof measures. The application of the proposed approach will allow the rapid forecasting of hazardous areas and significantly reduce the cost of shockproof measures.

Keywords: modeling, geomassive, coal seam, integration grid, forecasting, vertical stresses

A method for remote determination of the angular velocity of rotation of the blades of a wind generator based on digital processing of the video stream of this wind generator is considered. The main problems that are encountered with this method of measuring angular velocity are analyzed. The considered method for determining the rotation speed of the blades of a wind generator is possible provided that the frame rate is several times greater than the determined rotation frequency. The minimum possible error of this measurement method was found; the real error of measuring the angular velocity was calculated on a specific example.

Keywords: digital processing of the video stream, image stabilization of the wind generator, finding the contours of the rotor blades, estimation of the angular speed of rotation of the rotor

The article describes the main areas of implementation of "smart home" technology, energy-efficient solutions in the construction sector. Providing security and protection of housing, assistance to the elderly. The emergence of a new concept of "energy-saving business". The key parameters, types of modern technologies affecting the energy efficiency of the building, ways to minimize energy losses are considered. The analysis of energy-efficient solutions and the result of the introduction of intelligent technologies is presented. 2 things that make a house "smart".

Keywords: "smart home", energy efficiency, energy loss minimization, economical consumption of energy resources, intelligent technologies

The article presents theoretical calculations and studies of the possibility of parametric oscillations and parametric resonance arising in a polymer self-supporting thermoplastic pipe "Furanflex". The Furanflex thermoplastic, polymer liner is offered as a variant of a separate gas exhaust trunk during the reconstruction of boiler rooms and thermal power plants by heat generating companies.The article provides a detailed description and analysis of the occurrence of parametric oscillations. Examples of symmetric and asymmetric parametric oscillations are considered.Information and conclusions of the presented work are intended for a different range of readers, teachers, designers, students of construction specialties.This article should be of interest to utility managers and heat generating companies .

Keywords: chimney, ventilation duct, corrosion, repair, restoration of the chimney, condensate,protection of the chimney, lining, furanflex, thermoplastic liner,perimetric oscillation

The equations of multiple regression of air quality from factors affecting external sources of emission in the urban environment are obtained. A prototype of a forced air supply ventilation valve with air purification, placed in the outer wall of the building, using various sorbents together with a photocatalytic filter (a thin porous plate coated with titanium dioxide next to two UV lamps, UV-A range, 365 nm, 6 W each) was developed. Full-scale studies of five options for purifying the supply air were carried out. High quality of outdoor air purification from pollutants has the following options: shungite; zeolite; silica gel; photocatalytic filter, its purification efficiency was 96.39-99.98% for carbon oxide (II), 96.39-97.89% for phenol, 95.76-97.78% for formaldehyde, and 93.97-95.12% for aliphatic hydrocarbons (C1-C5). The results obtained can be used in multi-storey construction.

Keywords: forced air supply valve, prototype, pollutants, sorbent, shungite, zeolite, silica gel, photocatalytic filter

In this paper, we propose the option of constructing a multi-channel system of quantum key distribution with frequency coding, based on an electro-optical scheme of a system of quantum key distribution (hereinafter QKD) with pairs of amplitude modulator and phase modulator on the Alice side, and pairs of phase modulator and amplitude modulator on the Bob side ( hereinafter referred to as AMPM-PMAM), using a Comb generator, a multiplexer and a demultiplexer to form multiple parallel quantum subchannels.

Keywords: quantum cryptography, quantum key distribution; frequency coding, electro-optical photon modulation, amplitude-phase tandem modulation

The article provides a study and calculation of the dependence of the hazardous area resulting from the operation of the flare equipment on the height of the flare at which service equipment and personnel can operate

Keywords: flare unit, radiation intensity, safe operation zone, thermal voltage

he article presents the results of evaluating the ability of activated sludge, saturated with anammox bacteria, to adapt to mesophilic and lower temperature operating conditions. As the main temperature regimes, temperatures of 30, 25, 15, and 13 ° C were selected. The system showed stable operation at temperatures up to 15 ° С with the highest degree of purification with respect to ammonium nitrogen - 0.33 mg / dm3. At the same time, the concentration of nitrites taking into account forced nitritation reached 0.07 mg / dm3. An additional increase in the efficiency of the system requires structural changes in the adopted technological scheme of the bioreactor, however, the introduction of an internal recirculation system of attached biomass (with load) inside the anammox department is considered as an essential element of the system that ensures stability

Keywords: nitrification, denitrification, activated sludge, aeration tank, anammox, biological treatment, domestic wastewater, low-oxygen treatment method, energy saving, resource saving, ecology

The issues of organization of works with the use of expanding concrete, which are reinforced with carbon fiber, are raised. An example of the use of modern technologies in construction is considered. It describes the solution of some specific problems that arise when maintaining the quality of construction of complex buildings, attention is paid to the peculiarities of improving the quality of work performed.

Keywords: organization of construction; quality of construction and installation works

The article considers the results of development of water treatment technology for household drinking water in Semey, presents a comparative analysis of widely used disinfectants, and considers technological schemes for water disinfection with chlorine dioxide and a combined disinfectant " chlorine dioxide and chlorine".

Keywords: household drinking water, disinfectants, chlorine

This article presents the results of a parameters study on a piezoelectric flexible transducer of a beam type. The analysis was performed by the finite element method using the ANSYS Multiphysics software package. It is shown that there are optimal parameters ratios of the structural elements of the transducer under study for which it is the most effective

Keywords: bending-type piezoelectric transducer, piezoelectric element, elastic plate, resonance frequency, conversion coefficient, Electromechanical coupling coefficient

An impact on mechanochemical activation on morphology and structure of wood cellulose was examined. A comparative analysis of structure of sheet cellulose and fluffed cellulose was made using infrared spectroscopy and scanning microscopy. It was given that the cellulose I tranformed into a modification of cellulose II with more reacting power as a result of pulping. It ascertained that mechanochemical activation of the cellulose can increase the physical and chemical indicators of technical carboxymethylcellulose.

Keywords: cellulose, mechanochemical activation, carboxymethylcellulose

The equations of spinodal decay in binary systems in which there is a phase transition-improper decay are obtained. For the first time, spinodal equations for a phase transition with one multicomponent order parameter (two one-component) are obtained.

Keywords: binary solutions, spinodal decay, structural phase transition

The paper considers the results of research on the use of various types of approximations of concrete deformation diagrams on the example of calculating a large-span reinforced concrete truss with a length of 18 m. calculations were performed taking into account the physical nonlinearity of concrete and reinforcement. The following concrete deformation diagrams were used : bilinear, trilinear , and curved with a descending branch. The result of the calculation was the forces in the truss rods, the displacement and the width of the crack opening. Conclusions were made about the influence of the choice of the concrete deformation diagram on the calculation results.

Keywords: concrete, deformation diagram, approximation, physical nonlinearity, stress-strain state, longitudinal force, bending moment, displacement, crack resistance , truss