The design and construction of underwater pipeline crossings is a complex multifactorial task. Unfortunately, the existing recommendations on the design of these facilities, aimed at ensuring the reliability of structures, are not confirmed in operational practice. For example, with the trench method of building a single-pipe double-stranded structure, the distance recommended in the regulatory and technical documentation between the main and backup pipelines is often insufficient with intense deformation of the channel, which leads to a loss of bearing capacity of both strands of the underwater passage. Modern trenchless pipeline laying methods can minimize the risks of emergency situations. However, a number of factors, such as the pumping of corrosive products, the construction of oil and gas pipelines in difficult natural conditions (permafrost, increased seismic activity) require additional measures to ensure the reliability of underwater crossings. Our proposed option is to replace the single–pipe structure in trenchless pipeline laying with a two-pipe one. The objective of the study was to influence the fillers of the inter-tube space on the structural reliability of the pipeline and the feasibility of using the pipe-in-pipe construction method.

Keywords: underwater pipeline passage, pipe-in-pipe construction, trenchless technologies, inter-tube space filler

Bamboo as a building material has its own characteristics. It works well in stretching and bending. Bamboo has only longitudinal fibers that are prone to splitting, however these fibers are twisted in a knot. This phenomenon reduces the tensile strength. The mechanical properties of bamboo describe its reaction to physical influences. In general, bamboo has a high tensile strength parallel to the fibers. This article describes the mechanical properties of a bamboo rod depending on the loads, as well as modulus of elasticity of various types of bamboo. This article summarizes the experience of building buildings made of bamboo elements.

Keywords: bamboo, fibers, knot, joint, strength, construction, deformation, stretching, mechanical properties, anisotropic material

In this paper, a new intent and entity recognition model for the subject area of air passenger service, labelled as IRERAIR-TWIN, is developed using the ‘no code’ question-answer development platform ‘TWIN’. The advantages of the no-code platform were analysed in terms of the ease of developing an application question-answer system and reducing the amount of work involved in developing an application model for a narrow subject area. The results show that the ‘TWIN’ system provides an intuitive web-based user interface and a simpler approach to develop the semantic module of a question-answer system capable of solving application problems for a narrow subject area that are not overly complex. However, this approach has limitations for deep semantic analysis tasks, especially in complex contextual inference and processing of large text fragments. The paper concludes by emphasising that future research will focus on using ChatGPT-based ‘low code’ platforms and large language models to further improve the intelligence of the IRERAIR-TWIN model. This extension aims to broaden the scope of the scenarios.

Keywords: question-answering systems, No-code, Low-code, Intent recognition, Named entity recognition, Data annotation, Feature engineering, Pre-trained model, software development,End-user development

Orthogonal Frequency Division Multiplexing –OFDM) multiplexing technology is quite promising in wireless communication systems. Simultaneous use of multiple subcarriers allows for a relatively high information transfer rate. The use of mathematical models of discrete wavelet transformations instead of the fast Fourier transform (hereinafter FFT), allows you to increase the speed of signal processing by using modular codes of residue classes (hereinafter MKV). At the same time, these codes can be used to increase the noise immunity of systems with OFDM. It is known that block turbo codes (hereinafter referred to as TC) are widely used to combat packets of errors that occur when transmitting signals over a communication channel. The article presents a developed method for constructing modular turbocodes based on a system of residual classes (hereinafter MTKSOC). Obviously, the use of MTCS entails changes in the structure of the system with OFDM. Therefore, the development of a method for constructing a modular turbo code of SOC and a structural model of an interference-resistant system with OFDM using MTXOC is an urgent task. The purpose of the article is to increase the level of noise immunity of systems with OFDM, using wavelet transformations implemented in MKV instead of FFT, through the use of modular turbo code SOC.

Keywords: modular codes of residue classes, residual class system, modular turbo code of residual class system, error correction algorithm, structural model, multiplexing, orthogonal frequency division of channels

This paper is devoted to the quantitative assessment of the information security system. The authors propose to build a system that combines components with the properties of dynamism and protection efficiency. The proposed information security system includes two types of antivirus components, three data leakage prevention systems, and four intrusion detection and prevention systems. For clarity, the article provides a theoretical and graphical interpretation of the information security system. Each possible path in the system represents its state. It is shown that adding new components or subsystems leads to an increase in all possible states of the system, complicating the analysis by an intruder. Within the framework of this multi-component approach, each element of the system interacts with others, which helps to achieve the optimal level of efficiency in ensuring information security. In addition, the proposed approach is characterized by scalability, which ensures seamless integration of both individual components and subsystems as a whole.

Keywords: recomposition, information security system, DLP system, IPS/IDS system

Multilayer edge commutation in 3D integration technologies can simplify the design of microassemblies and reduce the length of edge electrical connections. However, this commutation is vulnerable to thermomechanical stresses and requires preliminary analysis of the product design. This paper shows the results of modeling various variants of multilayer edge commutation for 3D microassemblies, differing both in the dielectric material used at the edge redistribution layer and in the material for sealing the microassembly volume. It has been established that the lowest values ​​of thermomechanical stresses in commutation are characteristic of materials whose temperature coefficient of linear expansion is as close as possible to this parameter of conductors. At the same time, the use of composite dielectrics in redistribution layers leads to a more significant decrease in stresses than the use of more thermally stable unfilled polymers.

Keywords: 3D integration, packaging, thermomechanical stresses, polyimide, redistribution layer

This article presents a study aimed at evaluating the use of the Matlab Simulink software environment for the development of microcontroller systems of the STM32 family. The possibilities of Simulink in the field of modeling and testing control algorithms, as well as in generating code that can be directly applied to microcontrollers, are analyzed. The article describes in detail the process of creating conceptual models and their dynamic modeling. The advantages of using Simulink include speeding up the development process through automated assembly and the ability to adjust model parameters in real time. In addition, Simulink allows you to generate processor-optimized code, which significantly increases the efficiency of microcontroller systems. However, attention is also drawn to some limitations associated with using Simulink, such as the need to create a configuration file in STM32CubeMX and potential difficulties in configuring it. The article provides an in-depth analysis of the application of Simulink in the context of the development of STM32 microcontrollers and can become a key material for those who want to deepen their knowledge in this area.

Keywords: model-oriented programming, MatLab, Simulink, STM32, microcontroller, code generation, automatic control system, DC motor

The article deals with the influence of complex mineral additive "chemical water treatment sludge + flask or fly ash" on the frost resistance of building mortars depending on the redispersible polymer powder dosage from 0 to 3%. According to the results of research after 100 freeze-thaw cycles, the condition RF/R0 > 1.2 is met, and the k value according to clause 5.2.4 of GOST 10060-2012 after 100–125 freeze-thaw cycles ranged from 0.94 to 1.73, the minimum value of the relative modulus of elasticity EF/E0 = 0.97, and the residual expansion deformation did not exceed 0.03%. Building mortars with fly ash have higher frost resistance according to the bending strength criterion in comparison with mortars with flask. The frost resistance criterion for bending strength is more “strict” than the criteria according to GOST 10060-2012. It is not advisable to use a dosage of RPP greater than 2% for the production of building solutions with increased frost resistance requirements.

Keywords: frost resistance of building mortars, frost resistance criteria, redispersible polymer powders, compressive and flexural strength, elastic modulus, permanent expansion deformation

The article shows the importance of analyzing the state of strength properties of old wood during restoration work and monitoring the state of the structure. In particular, the physical and mechanical properties of wood during long-term use in an aquatic environment are analyzed. Changes in the chemical composition of wood as a result of use in the water of the Gulf of Finland are determined. Using the example of logs of the crib foundation of the Kronshlot fort, it is described how a change in the chemical composition of the material affects its strength properties.

Keywords: Mechanical properties of wood, long-term strength, chemical composition of wood, water-soluble extractive substances

Since 2017, EVRAZ ZSMK JSC has been developing and operating a mathematical model covering all processing stages from ore extraction to final products – SMM Forecast. The model will be used to calculate technical cases, plans, and parity prices for iron ore and coal, and its use brought more than 200 million rubles of economic effect in 2020 alone. The use of a universal mathematical model made it possible in 2023 to begin the development of a module for daily optimization of an agglomeration factory and blast furnace production. The article discusses the experience of EVRAZ ZSMK JSC in the development and implementation of a daily planning system based on the monthly planning model of SMM Forecast, as well as methods for achieving an acceptable speed of multi-period optimization. The SMM Forecast system was originally designed for end-to-end, scenario-based calculation of the main raw materials from ore and coal to finished products in a volumetric monthly planning. The system uses optimization algorithms to search for a global target function to maximize margin income under specified constraints. The mathematical model of redistribution uses the norms and technologies specified in the company's regulatory documents. At the same time, the model is universal and the transfer of algorithms from monthly to daily mode was carried out with minimal modifications. The article also discusses the difficulties encountered and various methods of solving these problems. The first problem faced by the developers was the low speed of optimization of the model in daily dynamics due to the strong complication of the optimization load. The calculation time has increased significantly, and to solve this problem, it took the introduction of a number of optimization cycles aimed at reducing the speed of solving equations, introducing variable boundaries, and determining starting points. As a result, the calculation time for one month was about 40 minutes. The second problem was the need to develop a complex supply management algorithm and optimize stacking at the sinter plant. As a result of solving this problem, a working tool has been developed that brings additional income to the enterprise.

Keywords: metallurgy, modeling, planning, daily planning, sintering plant, blast furnace shop, stacking

The production of ultra high molecular weight polyethylene (UHMWPE) is associated with significant dust emissions into the production room, so the aspiration system plays an important role in the technological process. The study of dust in industrial product waste released into the work area is one of the objectives of the ongoing research. This work provides information on the dispersed composition of ultra-high molecular weight polyethylene (UHMWPE) particles, and various graphs are constructed based on the data obtained. Data on the deposition rate of UHMWPE particles were obtained experimentally. A comparative analysis of the obtained data with theoretical data obtained using formulas was carried out.

Keywords: ultra high molecular weight polyethylene, UHMWPE, dispersed composition of ultra high molecular weight polyethylene, sedimentation rate of ultra high molecular weight polyethylene particles, method for studying the properties of raw high molecular weight

Expert work has been carried out to establish quality indicators for three types of concrete paving slabs: "Auriko", "Paving stone", "New City". The tests were carried out on selected samples in accordance with GOST 17608-2017. According to the test results, it was determined that only the samples of "Paving stones" tiles meet the requirements of GOST, other types of tiles revealed non-compliance of the studied samples with GOST 17608 in terms of water absorption and frost resistance.Frost resistance tests for Aurico and Novy Gorod product samples were interrupted after 15 freeze-thaw cycles due to the destruction of the samples.

Keywords: paving slabs, concrete, compressive strength, frost resistance, surface defect "sink"

The paper discusses the use of carbon fiber composite materials for reinforcement of specimens made of pipe sections in tension under the action of internal pressure. Experimental investigations of steel pipes under the action of internal pressure both without reinforcement and with different number of reinforcement layers with carbon tape are described. The main interest is in the joint operation of the pipe wall and external reinforcement elements. Significant influence of external reinforcement on stiffness and deformability of the specimens is noted.

Keywords: high-strength fiber, carbon fiber, carbon tape, adhesion layer, pipe, external reinforcement system, polymer composites, tensile strength

The public education project ""Dream School"", implemented in support of the federal school overhaul program, attracts students of architectural and design schools in the regions, which will allow them to simultaneously acquire applied competencies in the learning process. During the development of the design project, the need for specialists to conduct a preliminary design analysis was revealed, since one of the five schools did not meet the standards in terms of their spatial planning parameters. It is proposed to carry out the reconstruction of this educational institution. The premises of the dining room and the assembly hall are transferred to the annex block.

Keywords: school design project, school renovation, school recreation, public education project "Dream School", school reconstruction

The article deals with the results of research on the influence of the dosage and composition of the complex mineral additive containing chemical water treatment sludge with gaize, burnt rock or fly ash. The result of investigation is the equation for the change in shrinkage deformations over the time for mortars containing a complex mineral additive in comparison with a standard mixture without additives. There is evaluating of the influence of changes in the mortar moisture on the amount of shrinkage deformation. On the base of the research, we astablished the dependences of shrinkage deformations on the moisture content of the mortar, according to the composition and dosage of the complex mineral additive. The study revaels the influence of a complex mineral additive on shrinkage deformations. The equation has been obtained that describes the change in shrinkage deformations depending on the relative humidity and it has been shown that the tested mortars with a rational composition and dosage of a complex mineral additive with an average air humidity of the driest month in Rostov-on-Don of 47% will not exceed 0.55 mm/m . Shrinkage deformation with the ratio of the complex additive with fly ash or burnt rock 20-30% are 0.42-0.79 relative to the additive-free standard.

Keywords: dry construction mixture, shrinkage, mineral additive, mortar, chemical water treatment sludge, burnt rock, fly ash