Abstract: This article is devoted to the formation of a methodology for determining the duration of emergency recovery work, in case of damage to buildings and their structures from the effects of force factors, which is an important industrial and social task. The main indicator adopted in this article for calculating the duration is the duration criterion (Upr). In the course of the study, factors were formed and grouped according to segmental characteristics, based on the degree of their influence on the duration of emergency recovery operations, a multiple regression equation was compiled, which allowed taking into account the influence of the most significant factors on a single assessment scale. The findings of the study are supposed to be used to determine the duration of emergency recovery work. Thus, the methodology for determining the duration of work is an important tool in the complex of measures for the effective conduct of restoration work and minimizing costs.

Keywords: emergency recovery work, organizational and technological model, method of expert assessments, multiple regression equation, capital construction project, technical condition of the building, force impact, ranking, duration of emergency recovery

A two-dimensional coefficient inverse problem of thermal conductivity for a finite functionally graded cylinder is investigated. The thermal conductivity coefficient is considered to be variable along the radial and axial coordinates. The direct problem of finding the temperature distribution at different moments of time with known boundary conditions and the thermal conductivity coefficient is formulated in a weak statement and solved in the FreeFem++ finite element package. The influence of various two-dimensional power laws of the thermal conductivity coefficient on additional information (the temperature of the outer surface of the cylinder) is investigated. A projection-iteration scheme is constructed to solve the inverse problem. The thermal conductivity coefficient is presented as the sum of the initial approximation and the correction function specified as an expansion in a system of polynomials. At each stage of the iteration process, the expansion coefficients are calculated from the solution of the system of algebraic equations obtained by discretizing the operator equation of the first kind. The results of computational experiments on restoring various two-dimensional laws of change in the thermal conductivity coefficient are presented.

Keywords: functionally graded cylinder, finite element package FreeFem++, identification, thermal conductivity coefficient, inverse problem, iterative-projection approach, operator equation

5G wireless networks are of great interest for research. Network Slicing is one of the key technologies that allows efficient use of resources in fifth-generation networks. This paper considers a method of resource allocation in 5G wireless networks using Network Slicing technology. The paper examined a model for accessing radio network resources, which includes several solutions to improve service efficiency by configuring the logical part of the network. This model uses network slicing technology and elastic traffic. In the practical part of the work, transition intensity matrices were constructed for two different configurations.

Keywords: queuing system, 5G, two - service queuing system, resource allocation, Network Slicing, elastic traffic, minimum guaranteed bitrate

The work is devoted to the development and research of a heat exchanger for a contact gas-liquid heat exchanger. To increase the efficiency of heat transfer, the surface receiving heat is equipped with longitudinal fins and transverse partitions that form vortex structures in a turbulent gas flow. The expected decrease in gas temperature is 300-600 °C when cooled with water at a temperature of 50 °C. Simulation modeling has been carried out, including analysis of temperature distribution and hydraulic resistance, thermal power and stresses.

Keywords: heat exchanger, efficiency improvement, exhaust flue gas, heat recovery, mixing heat exchanger, numerical modeling, mathematical model, pixelation method

The article discusses the developed software application for synchronizing the class schedule in the Modeus system with other systems and various devices. The experience of creating a service that integrates the class schedule into the calendar application, ensuring the relevance of data and its availability to users is described in detail. The features of interaction with the Modeus platform are analyzed, including disadvantages such as unstable access and the need for manual data entry. Mechanisms for optimizing the schedule update using the iCalendar format are proposed, which allows automating processes and reducing the likelihood of errors. The results of implementing the developed application, its impact on improving the convenience of the educational process for students and teachers are presented, and the prospects for scaling the application to other educational institutions are considered.

Keywords: curriculum, university, Modeus, SaaS, software agent, calendar, information board, iCalendar, BOOCO, educational process

The article considers the numerical solution of the dynamic problem of interaction of a a building with a foundation. The developed algorithm and computer program are implemented on the example of calculating a 9-story frame building taking into account the operation of bored piles from the impact in the from of a given earthquake accelerogram.

Keywords: numerical modeling, bedrock, accelerogram, spline approximation, bored piles, partial frequencies, integration step

The article is devoted to the development of a new mathematical method for modeling radial plain bearings having a polymer coating with an axial groove on the bearing surface. For the calculation evaluation of technical solutions for wear resistance, the compressibility of a truly viscous lubricant under laminar flow conditions is taken into account. As a result, new mathematical models were obtained that make it possible to estimate the duration of the hydrodynamic flow regime of the lubricant, to prove the stability and possibility of changing lubrication modes from boundary to hydrodynamic, as well as to make a calculated assessment of the effect of compressibility of the lubricant and wear resistance on operational characteristics.

Keywords: modeling, mathematical method development, modified design, compressibility impact assessment

With the rapid development of technology and the widespread use of video surveillance, modeling the architecture of neural networks for human recognition in video is attracting increasing attention from researchers. This article presents a study of the use of neural networks (NN) as an interdisciplinary model for classifying objects in video, including solving the problem of face search. This highlights the versatility of neural networks in integrating trained data and accurately classifying objects, which is critical for ensuring security and efficiency of video surveillance. The study uses an analysis of various neural network architectures, as well as a study of their operating algorithms. Data obtained from a literature review and experimental results allow us to evaluate the effectiveness of solving the task of classifying objects in video using various architectures, without tying the study to a specific data set. The study confirms the possibility of using modern neural network architectures for human recognition in real-time video based on the experience of experts in the field of computer vision and machine learning. The active use of neural networks as a tool for video surveillance increases the safety of infrastructure facilities and the efficiency of security services. Ultimately, this article presents an analysis of neural network architectures for facial recognition in video streams, advocating their use as a key element in the development of modern video surveillance systems and ensuring public safety.

Keywords: neural networks, neural network architectures, video surveillance systems, real-time recognition, improving security, social well-being

The article presents results of self-compacting concrete with microsilica and grinded concrete crush additive study. The work presents concrete mix designes and mechanical tests results.Found that with the use of complex additive it is possible to obtain concrete of class B80 with a strength of at least 60 MPa after 7 days of hardening under normal conditions. High frost resistance of such concrete is noted. Concluded the possibility of complex additive application and potential advantages of its usage in self-compacting concrete.

Keywords: self-compacting concrete, silica, active mineral additives, concrete crushing screening, concrete, concrete scrap, finely ground filler, secondary filler, construction waste, determination of mechanical characteristics of concrete, high-strength concrete

The paper presents the results of experiments on the production of a composite material using small-lump wood waste based on soft wood varieties and waste products from non-plasticized polyvinyl chloride. An additional component of the raw material mixture was methylene chloride, in which polymer waste was dissolved. The solution was mixed with the filler, and then the solvent was pressed and removed at its boiling point. It is established that an increase in the degree of filling of the studied material contributes to the formation of a developed porous structure. The effect of increased porosity on the main operational properties, primarily thermal conductivity and water resistance, has been revealed. It is determined that the degree of filling, equal to 55 wt. %, makes it possible to obtain a material with the most effective combination of values of basic properties for use as a building thermal insulation. The practical application of the results of the work makes it possible to produce a low-cost thermal insulation material due to the joint disposal of heterogeneous waste.

Keywords: polymer composite material, thermal insulation material, polymer waste, wood waste, polyvinyl chloride, methylene chloride

The possibility of using expanded perlite dust (RUNWAY) in cement binder systems is being considered. A method for modifying the binder by joint mechanical activation of Portland cement, alumosilicate waste and hyperplasticizer is presented. The physico-chemical features of the modified runway make it possible to regulate the processes of hydration, phase formation, as well as the formation of the structural matrix of the composite. The compressive strength of the binder using RUNWAY as an active mineral additive increases by 36% with a decrease in density.

Keywords: technogenic raw materials, perlite, binder, dispersion, modification, mechanical activation, hydration, structure formation, phase formation, resource conservation

The paper provides a brief overview of publications on the application of mathematical modeling methods in the study of the patterns of functioning of hydroelectric power plants (HPPs). In particular, the following are considered: mathematical models of the total minimum water consumption for a cascade hydropower system in China; a mathematical model of hydropower plants; a mathematical model of two small hydroelectric power plants operating in tandem; accurate modeling of hydraulic transient characteristics in a complex drainage system. The task of filling in the gaps in the data concerning the operation of hydroelectric power plants is formulated. The approach to its solution is proposed to be based on the use of the method described in previous publications by one of the authors and based on the use of regression analysis apparatus. The specific task of filling in data gaps for a hydroelectric unit of one of the Siberian hydroelectric power plants has been solved. The following factors are used: active and reactive power of the electric generator, voltage, current and temperature of the stator iron, rotor current, air cooler hot air temperature.

Keywords: hydroelectric power plant, electric generator, data gaps, predictive analytics, regression model, adequacy criteria

One of the most important points in increasing the conversion component of a web resource is identifying the most attractive places for the site user. To identify these locations, a site user activity data visualization tool was created that provides a visual representation of each user action on a site page.

Keywords: heat map, site, oculograph, fixation, priority area

The paper presents the formulation of problems of minimization and maximization of a linear functional with inequality constraints on the vector of admissible program motions and equality constraints specified by a linear manifold. An analytical solution is synthesized that determines the projection operator for solving the specified mathematical programming problems with equality constraints and inequalities. An analytical solution is obtained that determines the boundary values ​​of the Lagrange multiplier for the synthesized projection operator. The correctness of the obtained solution is illustrated.

Keywords: mathematical programming, linear functional, projection operators, admissible program motions, stabilization of program motions, SimInTech

The article considers a variant of constructing a digital twin model for diagnostics of operation of a mechanical gear transmission - a reducer consisting of a pair of cylindrical gears. The basis of the considered digital twin model is an adaptive learning vibration mathematical model of the static operating mode when gears rotate at a constant speed. The vibration signals of the reducer, recorded by accelerometers and effective for detecting and diagnosing faults, are used as the main information measured at the facility. The detected faults are cracking, wear, chipping and pitting of teeth. A special feature of the implemented digital twin is the ability to simultaneously detect faults of several teeth at once, both on the driving and driven gears, by time and frequency characteristics, as well as the ability to determine the main technical data of a specific reducer by vibration characteristics.

Keywords: diagnostic mathematical model, digital twin, vibration diagnostics, mechanical gearbox, tooth defect, diagnostic signal, vibration power spectrum, synchronously averaged time characteristic