A passive device, the heat pipe has the capacity to transfer massive volumes of heat over small cross-sectional areas at extremely small temperature differentials heat pipes are extensively employed in many engineering applications owing to their exceptional efficiency in heat transfer, enabling the transmission of heat over considerable distances while minimizing temperature fluctuations. It is a heat transmission technique that is becoming more and more useful. The fundamental design of a heat pipe consists of an empty chamber placed after a cylinder or square filled with a vaporizable working fluid. This technique of heat transfer is used in solar water heaters, computers, solar power boards, laptops, mobile devices, and electronic circuits. Devices that require a large volume of heat transformations and heat management greatly benefit from the usage of heat pipes. This study investigates the influence of working fluid and pipe material on the performance of heat pipes. The researchers developed a complete experimental configuration to examine the performance attributes of heat pipes, encompassing thermal conductivity, heat transfer coefficient, and overall efficiency. The study examined a range of working fluids, including water, aceton, and ethnol, as well as different pipe materials such as copper, aluminium, and brass. The findings demonstrate notable disparities in performance indicators depending on the selection of the working fluid and pipe material. The entire heat transfer capability is significantly influenced by the thermal conductivity of the working fluid, whereby specific fluids demonstrate higher performance compared to others. The heat transfer efficiency is significantly influenced by the thermal conductivity and surface characteristics of the pipe material. Furthermore, the compatibility between the working fluid and pipe material significantly influences the long-term reliability and durability of heat pipes. Corrosion, material degradation, and phase change characteristics are critical factors that must be carefully considered when selecting the optimal combination of working fluid and pipe material. This study provides valuable insights into the design and optimization of heat pipes for various thermal management applications, highlighting the importance of selecting appropriate working fluids and pipe materials to enhance performance and reliability.

The article describes a method for calculating the composition of cement-based aerated concrete with a microaggregate made of granite rock for prefabricated and monolithic construction, including construction using 3D concreting technology. The method is designed for calculating the compositions of aerated concrete for thermal insulation and thermal insulation and structural purposes (in the range of axial compression strength classes: B0.5–B5, and average density grades D200–D900) using casting technology, with the aerated concrete mixture expanding in the cavities of molds, removable and non-removable formwork, including wall structures built using 3D concrete technology, without vibration. The developed and experimentally and productionally tested methodology is based on the use of fine-grained fractions extracted from granite screenings, a technological waste from the production of granite crushed stone at State Unitary Enterprise Granit in Mikashevichi. In the article, the proposed methodology is presented using the example of calculating the composition of structural and thermal insulation aerated concrete with a class of axial compression strength of B0.5 and a medium density of D400, in accordance with the provisions of STB [Standards of the Republic of Belarus] 1570–2005. The technique is an integral part of the author's development of an energy-saving technology for cellular cement aerated concrete without autoclave hardening, which makes it possible to eliminate energy-consuming, technically complex and expensive autoclave equipment in the manufacture of prefabricated products. Due to the possibility of hardening such aerated concrete in natural conditions, it ensures the use of heat-insulating aerated concrete obtained from it in monolithic construction, including heat and sound insulation of building walls, constructed using 3D concreting technology, as well as the installation of building structures in removable and non-removable formwork using aerated concrete for structural and thermal insulation purposes. The Belarusian National Technical University is ready to cooperate with interested enterprises and organizations in terms of using the article's material and in other areas of construction.

A solution for optimizing a rectangular reinforced concrete slab with a rib-reinforced technological opening is proposed. The static analysis was performed using the Sturm computer program, written in the Pascal (Delphi) algorithmic language. This article presents an effective method for parametric optimization using a 2D elastoplastic finite element model. The load is applied to the finite element model through the nodes connecting the elements. Considering the properties of concrete, a nonlinear constitutive law for the deformation of finite elements with changing stiffness before and after crack formation was adopted. Accordingly, the Seidel approximation method is used to determine the stress-strain state of the slab. The cost of concrete and reinforcement used in manufacturing the slab is taken as the objective function. The solution is constrained by the slab thickness, rib height, maximum deflection, stress, and bending moment. The optimal solution is determined in a discrete space constructed on the optimization variables: slab thickness, rib height, and reinforcement area. Initially, based on scanning results on a grid of a selected individual layer, built on the hpl and hreb parameters, a “forbidden” region of the space constrained by the limits is established. The search for the optimal solution is performed on the “permitted” part of the space. Then the next subsequent layer is considered, and the optimal solution is likewise determined within it. The process continues until all layers of the search space have been examined. The global minimum of the objective function is selected from all found solutions. This method guarantees that the found solution is absolute.

The Anti-lock Braking System (ABS) has become an essential safety feature in modern vehicles due to its capability to prevent wheel lock during braking, thereby preserving vehicle stability and steering controllability. As a typical mechatronic system, ABS integrates hydraulic, mechanical, and electronic subsystems governed by an electronic control unit (ECU). This study proposes a multidisciplinary co-simulation framework for investigating the braking performance of a passenger vehicle equipped with ABS. The hydraulic behavior of the system is modeled using AMESim Simcenter, while the vehicle longitudinal dynamics and control strategy are implemented in MATLAB Simulink. In the AMESim environment, a fourchannel hydraulic ABS modulator is developed, where the ECU control signal serves as the input and the brake circuit pressure is generated as the output. This pressure signal is subsequently transmitted to the Simulink model, which utilizes it to evaluate wheel slip behavior under braking conditions at a specified tire–road adhesion coefficient, forming a closed-loop simulation architecture. To enhance braking efficiency under varying slip conditions, a hybrid control strategy combining a conventional PID controller with fuzzy logic is introduced. The proposed co-simulation structure enables real-time bidirectional interaction between the physical hydraulic subsystem and the control module: pressure outputs from AMESim are fed into Simulink, while control signals generated in Simulink are used to actuate the solenoid valves within the AMESim model. An experimental test rig was established to validate the proposed model and to assess the effectiveness of the control algorithm under real operating conditions. Experimental results demonstrate that the vehicle can decelerate from an initial speed of 90 km/h to a complete stop without wheel lock in approximately 2.54 seconds, corresponding to a braking distance of 30.48 meters. Compared with a conventional hydraulic ABS, the proposed control strategy reduces braking time and stopping distance by approximately 8.5 % and 6.5 %, respectively. Furthermore, a close agreement between simulation and experimental results is observed, with deviations of 4.4 % in braking time, less than 0.5 % in stopping distance, and 3.9 % in deceleration, confirming the accuracy and reliability of the developed model. The results indicate that the integration of PID control with fuzzy logic significantly enhances ABS performance, ensuring stable and effective braking under emergency conditions across varying road adhesion scenarios.

In the context of increasing congestion on the road network of large cities, the most effective measure, according to domestic and foreign experts, is the development of urban passenger transport, and especially the creation of priority conditions for its movement. However, in today's conditions, it is quite difficult to assess the effectiveness of this measure, especially when the creation of a whole system of dedicated lanes is planned. Taking this into account, the purpose of this work is to develop methods for predicting the speed of urban passenger transport within the framework of creating priority conditions for traffic. To solve this problem, the author has reviewed existing methods and proposed his own methods. The first method for predicting message speed is based on analyzing the speed of passenger traffic during off-peak periods. Such a forecast can be carried out both by means of the counters located inside the rolling stock, and by means of the navigation systems installed inside the bus. The second method of forecasting is based on the data of the geoinformation system “Yandex traffic jams”. The essence of the method is to obtain data on the speed of the traffic flow on the network and its recalculation for bus traffic, taking into account the time losses at stopping points. The results of the study showed that the implementation of measures to allocate separate lanes for passenger transport in the city of Yekaterinburg will allow to increase the average speed of urban passenger transport on the network during peak hours by 27 %. At the same time, the average travel time of a passenger during peak hours will decrease by 35 %. The results obtained can be used in cities of various sizes, and it is especially effective to apply such methods when developing transport planning documents, such as the “Сomprehensive Traffic Management Scheme” and “Comprehensive Transport Scheme”.

The research results described in the article are devoted to issues of optimizing scheduled maintenance and necessary repairs of passenger cars. The paper assesses the availability of mobile infrastructure that can ensure timely and highquality repairs, enabling the efficient and effective use of motor vehicles for public needs. Currently, scheduled maintenance and repairs of vehicles are carried out at stationary stations, which requires time and material costs from owners. This article describes a study exploring the feasibility of using mobile service stations. It presents the results of the conducted assessment of demand for services and types of work required, as well as a market study of the use of such stations. The effective radius of the station's use is presented, its main capabilities and the target audience of clients who wish to service their cars at the mobile station are examined. Areas with a high density of vehicles have shown particular relevance in using mobile service stations for maintenance and repairs. The aim of the work described in the article is to justify the development, design and use of mobile service stations as a means of improving the infrastructure for servicing passenger cars. This article provides a calculation of the expected costs of operating a mobile station, justifies the cost of work, and determines the minimum effective cost of calling a mobile technical service station. Practical recommendations are given for the effective use of a mobile service station for passenger cars.

It is noted that in practice, the determination of the residual service life of units is performed either subjectively, or this indicator is not assessed at all due to the lack of necessary methods and means, while a large number of units are written off or sent for labor-intensive repairs with a significant portion of unused service life. The objective of this study was to develop a method for assessing the residual service life of an individual unit using the values of structural parameters associated with the measured diagnostic parameters by vibroacoustic methods, as well as assessing the total residual service life of a group of similar units. Based on the examination of a batch of engines, a method for assessing the residual service life of automotive units is proposed, which includes: the selection of the main structural parameter of the unit under study, a description of the variational series of predicted values of the total service life of individual units with the determination of the probability density of its distribution, the total service life, the probability density of the distribution of the residual service life, and the total residual service life. It has been established that the probability density function of the total service life obeys the Weibull law, while the residual service life obeys the exponential law. It has been shown that the loss of the total service life of units before their decommissioning, write-off, or sending them for labor-intensive repairs amounts to 20–40% on an industry or enterprise scale. The obtained data allows us to provide an economic assessment of the conservation of the remaining service life of operating units. If repair work is scheduled using preliminary diagnostic studies, the range of replaceable parts included in connections whose condition is close to the ultimate limit will be determined.

A frequency-dependent ceramic material with high temperature stability of the resonant frequency has been obtained, which guarantees stable operation of devices based on it when temperatures change. The article presents the results of the influence of the production conditions on the microstructure and dielectric properties, as well as on the microwave parameters of ceramics. The solid-phase synthesis method was used to obtain the material. The synthesis was carried out at a temperature of 1000 °C for 2 h with subsequent thermal firing. It is shown that the optimal microwave properties of BaSm2Ti4O12 ceramics are obtained at sintering temperatures in the range of 1360–1380 °C. It is established that by changing the sintering temperature, the dielectric permeability of the ceramic material can be increased almost twice. The resonant frequencies of ceramics for various sintering temperature regimes were determined experimentally. The resonant frequencies of the materials range from 6.7 to 8.9 GHz. It is found that the quality factor of the ceramic material near the resonant frequencies significantly depends on the operating temperatures. At operating temperatures above 40 °C, a decrease in the quality factor of the ceramic material by 22–30 % is observed. By studying the frequency dependencies of the real and imaginary parts of the dielectric permittivity of the ceramics under study, possible polarization mechanisms were established. It is shown that the resonant nature of the dielectric permittivity dispersion is characteristic of the 100–900 MHz frequency range. At gigahertz frequencies, dipole and migration polarization prevail. Due to their properties in the gigahertz frequency range, the ceramics obtained can be used for the manufacture of substrates for microstrip antennas and microwave circuits, as well as for dielectric resonator antennas and components of satellite and mobile communication systems.

The article presents a study of the kinetics of heat transfer using experimental data on the moisture exchange of thin flat ceramic, asbestos and felt wet plates based on the drying kinetics equation. The drying process was studied at a temperature of 90, 120, 150 °C and an air speed of 3, 5, 10 m/s. The relationships between moisture and heat exchange were established based on the drying kinetics equation, the Rehbinder number and the drying temperature coefficient. Based on the relative drying rate, equations for the heat flux density for the second drying period are established. Equations for the heat flux density for the second drying period based on the relative drying rate, equations for calculating average temperatures in the period of decreasing drying rate based on the drying temperature coefficient and the ratio of drying time by drying periods are determined. Relationships were established between complex variables, between the ratios of drying time by periods and the current moisture content to the critical one. It is demonstrated that cross-processing of experimental data on drying of specific materials allows to determine the critical moisture content of materials. A method for processing experimental data is presented for determining the critical moisture content of the material, experimental drying curves for ceramics, asbestos, and felt under different drying conditions. A formula is presented for determining the relative drying rate as a function of the ratio of the current moisture content to the critical one. The results of calculating heat flux densities, relative drying rates and average integral temperatures for the period of decreasing drying rate in the drying processes of ceramics, asbestos, and felt are presented, and a comparison of the calculated values with experimental data is provided. The error in the values lies within the error zone of the experimental data processing.

The relevance of research in the field of supply chain resilience has increased dramatically due to global crises such as the COVID-19 pandemic, geopolitical tensions and climate change. The article examines specific aspects of practical application of the methodology for quantitative assessment of the fault tolerance of supply chains, taking into account transport and logistics activities. A strategic adaptation model has been developed, which logically completes the development of a comprehensive QSCR methodology, transforming it from a passive analysis tool into an active tool for proactive management. It allows companies to quantify and compare various scenarios for the development of their supply chains; economically justify investments in improving reliability and digitalization; and move from a “firefighting” mode to systematic risk management, which is a factor in survival and competitiveness in the new economic reality. The implementation of this approach at the level of enterprises in the Republic of Belarus and the EAEU will improve the resilience of their business models, reduce their dependence on external shocks, and strengthen their position in regional and global value chains. Practical recommendations have been developed, grouped into three levels: corporate, industry (within the EAEU), and national.