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The article covers stability and accuracy for restoration of uneven sampled signals, using basis functions. The accuracy and stability are explored for different transfer system orders, period between basis functions and offset of the basis functions system against restored samples.

The article deals with the issues of joint use of a low-temperature solar collector and a heat pump in a solar heating system, the combination of which allows for high energy efficiency and stable operation of the system for the entire period of the year. The study and development of innovative technologies in alternative energy is a topical issue of today. Based on the actual statistical climatic data of the city of Omsk, a thermal calculation of the solar collector and the air heat pump in the heat supply system of the building was made. The values of solar insolation and the angle of inclination for the city of Omsk by months determined depending on latitude are given, the dependence of the change in solar insolation of the city of Omsk on the period of the year is plotted. The proposed scheme allows creating high energy efficiency and stable operation of the system during the summer and transitional months of the year. A method for calculating the generation of thermal energy using a combined system is given. The required number of tubes of solar vacuum tubular collector SVK-20A has been calculated. The work of an air heat pump and a solar collector according to a bivalent scheme is proposed, and a graph of the heat load of the heating system is also considered. The thermophysical properties of the working substance of a solar collector and an air heat pump are studied with a change in ambient temperature, the dependence of the freezing point of aqueous solutions of ethylene glycol and propylene glycol on the mass concentration of glycol is studied. A technical calculation of the COP coefficient for one of the educational buildings of OSTU was made. An effective option for using this system is proposed - heating systems «warm floor», «warm walls» or «warm ceiling».

In article the algorithm of operation of the existing regime automatic equipment of transforming aggregates is considered. Earlier it was read that use of automatic equipment of switching on switch-off of reserve transforming aggregates is an effective remedy of lowering of losses in case of regulation of power of substation depending on tractive loading. Defining factors of assessment of efficiency of automatic equipment are the current and temporal settings, and also restriction of number of switchings in days. The analysis of diagrams of tractive loading showed that there is rather large number of temporal intervals where operation of automatic equipment is ineffective. On the one hand it is connected to the fact that loading is above a point of equality of losses in case of one and two transforming aggregates quite short time, and automatic equipment connects the reserve transforming aggregate already in the course of lowering of loading and disconnects it after a temporal setting. On the other hand - operating restriction of number of switchings of the reserve transforming aggregate in days doesn't allow to gain the considerable economic effect. The decision on use of regime automatic equipment with the existing settings can be the positive if at the same time the estimated effect in the form of abbreviation of losses of the electric power is above cumulative damage from switching of the reserve transforming aggregate. Regime automatic equipment in most cases, it is necessary to consider not as means of obtaining economic effect, and as means of reliability augmentation of operation of semiconductor rectifiers at the peak moments of loading what in turn influences reliability of electrical power supply of pull of trains in general.

The growth of production capacity requires a constant increase in fuel consumption, which leads to an inevitable decrease in fossil fuels, whose reserves are limited. As a result, it is necessary to gradually switch to the use of secondary energy resources, in particular, the use of secondary gases generated as a result of production processes. This article discusses the use of natural gas conversion by adding it to a high-temperature converter gas stream in order to reduce its temperature to reduce the thermal load on the heating surface and further use as the main fuel in power units. Using the Ansys Fluent universal software package, a computational model of a natural fuel converter gas pipeline was developed, and the distribution contours of the composition and temperature of the fuel mixture formed by the chemical interaction of gases were obtained. The analysis of the obtained fuel mixture was carried out, and the efficiency of the obtained synthesis gas was compared with the initial fuel. It was shown that as a result of a chemical reaction, the resulting gas has an increase in thermal efficiency by 64 %. The results of this study demonstrate the possibility of further application of the resulting fuel mixture as the main fuel for technological processes.

The article presents the results of measurements of electricity on active and passive sectioning posts the traction power supply system direct current sections of railways with III and IV path profile type. Basic characteristics of operating modes sectioning posts for the purpose of assessing the amount of electricity transferred and duration of work electricity storage in different modes are considered. The most observed voltage values, volumes of transmitted energy and duration of each case are defined. Choice of theoretical distribution laws, allowing to use the experimental values obtained in further calculations in modeling of operating modes electricity storage is completed.

The article deals with the application and use of heat pump installations as a low-potential source of heat energy to provide consumers with heat energy in the building heating system. Today, one of the most environmentally friendly and economical alternative sources of thermal energy is a heat pump unit. The use of these devices will reduce COemissions. The main advantages and disadvantages that appear during the operation of heat pumps are listed. Based on the results of tests of boilers using organic fuels (coal, fuel oil, natural gas)and low-potential heat sources with an electric drive, the dependences of the heat transformation coefficient of the heat pump and the efficiency of boilers operating on organic fuels on the cost of conventional fuel per unit of released energy are constructed. The coefficient of heat transformation of heat pump installations in the range of changes in operating parameters 3,0 < µ < 5,0 is determined. A graph of the dependence of the energy conversion coefficient on the temperature of the heat carrier in the heating system and the ambient temperature is constructed. A schematic diagram of the connection of a heat pump installation to the building heating system is proposed. Studies were conducted in the period from April 1 to April 21, 2021 in the laboratory auditorium of the educational building of OmGUPSa and the readings of the main parameters of the operation of the heat pump unit with the Vitocal 242-S heat pump were recorded. Based on the results of the main parameters, the following are calculated: the thermal load on the room heating system; the temperature of the coolant in the supply pipeline; the amount of electricity consumed by the heat pump; the conversion coefficient of the COР. The optimal values for this heat pump unit under the specified operating modes are estimated.