When developing large information-measuring and control systems, special attention must be paid to the interaction of various blocks of the system with each other. For example, the structure of a software-hardware measuring channel consists of four consecutively connected elements: primary converter; analog-to-digital converter; software dynamic converter; digital to analog converter. To find the parameters of the measurement channel error, mathematical models were constructed for each of the blocks. Simulation modeling of the measuring channel was carried out. As the input signal, the first-order aperiodic link model is taken. To generate the interference signal, a random number generator with a noise level of 0.5 is used. The error for the measuring channel is found. The suggested mathematical model allows to find the tuning coefficients of the software of the measuring channel, which ensure the minimum information loss in the software-hardware measuring channel. The resulting model can be used in automatic control systems for the current identification of regulator settings.

Keywords: model of measuring channel, model of primary converter, adjustment of coefficients, error of measuring channel

The article considers the question of finding similarity between objects containing unstructured information based on the spectra of two objects. To find the spectrum, we use the adjacency matrix of the graph. The similarity between objects of comparison is determined using the approach based on the singular expansion of the graph contiguity matrices. Also in the article the existing solutions are considered and examples are given of the areas of possible application of the described approach

Keywords: spectrum of the graph, singular decomposition, adjacency matrix, unstructured information, analysis of large arrays of information

The article considers the experimental estimation of the heat transfer coefficient in a hybrid immersion cooling system with contact point cooling and dry zones. The change in the heat transfer coefficient is made through a change in the Reynolds number for the flow of the coolant in the immersion cooling system. The experimental investigation is carried out on the basis of a numerical simulation model of the process under study. As a result, the dependences of the thermal resistance of the processor-heat exchanger system on the heat transfer coefficient and on the Reynolds number of the turbulent flow were obtained, and the results with the simulation results were estimated. It is found that, with an increase in the Reynolds number, the heat transfer intensification is weaker than the theoretical one. The refinement coefficients for the case under consideration are found.

Keywords: processor, heat flow, thermal resistance, Laplace equation, turbulent flow, Reynolds number, heat transfer, immersion cooling system, immersion cooling system, cavitation

In this study, the task is to simulate the cooling system of supercomputers with a heat pump on the reverse Stirling cycle by numerical simulation of heat transfer processes in the object under study. The results of numerical simulation of heat transfer processes in the superheater processor cooling system with a heat pump on the reverse cycle are presented. A numerical model of the heat transfer process was investigated. As a result, the dependencies of the required thermal lift of the heat pump are obtained taking into account the thermal resistance of the system. The first liquid cooling circuit - the cold cylinder of the heat pump and the hot cylinder system - the second liquid cooling circuit, depending on the heat transfer coefficient of the heat pump.

Keywords: processor, heat flow, thermal resistance, Laplace equation, heat pump, heat exchange, Stirling backflow, cooling system

The article presents the results of studies conducted by foreign and Russian authors on the assessment of urban air pollution with fine dust of natural origin

Keywords: air quality, dust, fine particles PM10, natural origin, atmosphere

The work of the sensors of passenger traffic control in conditions of a dense stream of people in the controlled section of the doorway was conducted. The results showed the possibility of determining the direction of movement of a person due to a change in the distance between the sensor and the moving person. The interference due to the high density of passenger traffic, which, however, does not lead, however, to the development of the corresponding algorithms, to false alarms of the sensors is detected. However, additional field studies are required on the vehicle of the passenger counting device based on ultrasonic distance measurement sensors

Keywords: passenger, ultrasound, passenger transport, road transport, distance sensor, Arduino, bus

Flat bending stability problem of constant rectangular transverse section wooden beam, loaded by a concentrated force in the middle of the span is considered. Differential equation is provided for the cases when force is located not in the center of gravity. The solution of the equation is generated numerically by the method of finite differences. For the case of applying a load at the center of gravity, the problem reduces to a generalized secular equation. In other cases, the iterative algorithm developed by the authors is implemented, in the package Matlab. A relationship is obtained between the value of the critical force and the position of the load application point. For this dependence, a linear approximating function is chosen. A comparison of the results obtained by the authors with an analytical solution using the Bessel functions is performed.

Keywords: flat bending stability, secular equation, finite difference method, iteration process

The method of calculation gamma percentage fatigue resource of an arrow shovel excavator. Using this method can most accurately determine the distribution of the extreme members of samples and the corresponding shifts of the Weibull distribution. It was found that to calculate the shifts do not have, you can use only the extreme members of samples.

Keywords: reliability, probability, resource, sample, excavator

An overview of the basic schemes, characteristics, and directions of development of microwave photonics systems is presented in this paper in terms of requirements defining the parameters of external amplitude-phase modulation of laser radiation as a key process for the formation of radio frequency signals in the optical range for systems with polarization multiplexing of polyharmonic signals.

Keywords: microwave photonics; external amplitude and phase modulation, optical generation of radio frequency signals; generation of poly-harmonic optical signals with microwave frequency components

microwave photonics; external amplitude and phase modulation, optical generation of radio frequency signals; generation of poly-harmonic optical signals with microwave frequency components

Keywords: microwave photonics; external amplitude and phase modulation, optical generation of radio frequency signals; generation of poly-harmonic optical signals with microwave frequency components

The article is devoted to the issues of marketing costs evaluation in the construction project cost's management. The methods of determining the marketing cost in the construction sector within the specifics of the industry are issued.

Keywords: marketing costs, project cost management, methods of marketing costs estimation

The field studies of the device in a controlled section of the doorway of the trolleybus were carried out. Studies have shown the operability of the device with the appropriate information processing algorithm, which allows to extract an information signal from short-term interference. It is necessary to carry out on the vehicle additional field studies of the passenger counting device based on ultrasonic proximity sensors aimed at eliminating the reflection of interference from the walls and, accordingly, improving the accuracy of counting the number of incoming and outgoing passengers.

Keywords: passenger, ultrasound, passenger transport, road transport, distance sensor, Arduino, trolleybus

The experience of applying centrifugation as a molding and compacting method has opened new prospects for the production of highly efficient reinforced concrete products. The experience of production of centrifuged power line supports at one of the enterprises of the Socialist Republic of Vietnam is analyzed. The studies aimed at studying the change in the composition of the mixture during centrifugation and the kinetics of the strength of centrifuged concrete were carried out. The dependence of the ultimate strength of centrifuged concrete on compression on the value of B / W after HMT (heat and moisture treatment) and at the age of 3-7 days was studied. Conclusions are made on the correction of the known quantitative regularities of the change in the strength of vibrating concrete from the value of B / W and the porosity, taking into account the heterogeneity of the structure of the centrifuged concrete over the cross section.

Keywords: centrifugation, heavy concrete, concrete mixture, power line supports, additives to concrete, enterprises for the production of reinforced concrete products

A constructive solution of the walls of wooden houses from round logs or a profiled beam, which is installed vertically (wooden element) is considered. It is proposed to arrange two longitudinal milled grooves of a rectangular shape located in the diametral plane of the section of the log for the installation of sheet plywood keys, which makes it possible to include in the joint work adjacent contiguous elements when working on bending from the plane of the wall. The variant of the strapping device, it is proposed to use metal rolling profiles of Channel and I-sections, connected with metal tube elements (box section) mounted in the corners of the frame.

Keywords: round log, profiled beam, sheet plywood keys, tubular section elements

The evolution of organizational and technological methods of construction of public buildings during the Russian middle Ages from aesthetic, economic and socio-political aspects is studied. This paper examines the impact of the economic component of the state on the possibility of construction of the building, its carrying capacity. The a priori necessity of construction of religious building in the Middle ages even in the conditions of permanent economic crisis is proved

Keywords: organization of construction; construction economics, history of architecture, history of the construction industry