The object of study is flexural reinforced concrete elements without transverse reinforcement under the action of shear forces. The calculation of reinforced concrete beams for shear is a complex problem, and its formulas are obtained by experimental or semi-empirical methods on the basis of various theoretical calculation models. In Russian standards, the calculations of reinforced concrete structures under the action of shear forces are performed based on the length of the most dangerous projection of the inclined section on the longitudinal axis of the element, and the formulas lack parameters that would take into account the influence of longitudinal reinforcement on the strength of inclined sections. The novelty of the present research is that the author, based on the theory of Prof. A.S. Zalesov, proposed a new approach to determine the shear strength of inclined sections of elements reinforced without stirrups. In the new approach, an analytical expression is obtained that takes into account the work of longitudinal regular reinforcement by introducing a longitudinal reinforcement coefficient. Examples of calculations performed according to the proposed methodology and SP 63.13330.2018 are given, where a series of experimentally tested specimens are taken for comparative calculation. The results of comparative calculations have shown the adequacy of the new approach to determine the strength of inclined sections of reinforced concrete elements reinforced without stirrups.

Keywords: reinforced concrete beam, beams without stirrups, inclined crack, shear stress, normal stress, strength, shear force

3D – printing is the quickly expending area of modern industry. In this review is carrying review of novel US patents on this topics.

Keywords: 3D - printing; application in civil & military engineering; application in industry and medicine

Road surface quality assessment is one of the most urgent tasks in the world. To solve it, there are many systems that mainly interact with images of the roadway. They work on the basis of both traditional methods (machine learning is not used) and machine learning algorithms. Traditional approaches, for example, include methods for edge detection in images that are the object of this study. However, each of the algorithms has certain features. For example, some of them allow to get a processed version of the original photo faster. The following methods were selected for analysis: "Canny algorithm", "Kirsch operator", "Laplace Operator", "Marr-Hildreth algorithm", "Prewitt operator" and "Sobel Operator". The main indicator of effectiveness in the study is the average time to receive the processed photo. The initial material of the experiment is 10 different images of the road surface in 5 sizes (1000x1000, 894x894, 775x775, 632x632, 447x447) in bmp, jpg, png formats. The study found that the "Kirsch operator", "Laplace Operator" and "Prewitt Operator" and "Sobel operator" have a linear dependence of O(n), the "Canny algorithm" and the "Marr-Hildreth algorithm" have a quadratic character of O(n2). The best results are demonstrated by the "Prewitt Operator" and the "Sobel Operator".

Keywords: comparison, effectiveness, method, edge detection, image, photo, road surface, dependence, size, format

This paper is devoted to optimization of surface acoustic wave bandpass filters with apodized interdigital transducers (IDT). Iterative Parks-McClellan algorithm is applied to estimate the apodization coefficients of the IDT fingers. A family of corresponding subroutines is developed in the Matlab mathematical package. The simulation results of the SAW filter optimized design are illustrated. For the refined estimation of the filter frequency response COM-based P-Matrices are employed. The results obtained in this study constitute a set of tools for the practical calculation of apodized IDTs and filters according to a given specification. Subroutines implementing COM-based P-Matrices can be utilized as part of programs for frequency-selective SAW devices design.

Keywords: acoustoelectronics, apodization, approximation, interdigitated transducer, impulse response, surface acoustic wave, optimization, piezoelectricity, filter, frequency response

This paper considers the development and training of a neural network model for the identification of the species and quantitative composition of pollen, which will subsequently be used to determine the botanical origin of honey and quantitative calculations of pollen grains contained in a certain mass of honey. The main purpose of the study is to create a model that can effectively distinguish the morphology of pollen grains present in honey, determine their quantitative and qualitative composition, which will improve product quality control, as well as identify its botanical and geographical origin. For this purpose, similar works on pollen classification were analyzed. Pwtorch was chosen as the framework for creating a neural network model, which provides the possibility of detailed configuration of the model. The result of the work is a trained model capable of classifying pollen grains.

Keywords: neural networks, classification task, pollen classification, convolutional neural networks, PyTorch

A numerical study of heat transfer and hydrodynamics in plate heat exchangers with corrugated fins was carried out. The effect of corrugation pitch on heat flow and pressure drop was studied. The study was carried out using computational fluid dynamics in the ANSYS software package (v. 19.2). The results of the study showed that increasing the corrugation pitch from n = 5 to n = 9 leads to an increase in heat flow of 10.83% and a pressure drop of 28.30%.

Keywords: plate-fin heat exchanger, corrugated fins, heat transfer, hydrodynamics, numerical study, calculation, heat flow, pressure drop, energy efficiency, cooling system

As of today, in Vietnam, to ensure stability and improve the quality of asphalt concrete, the main focus is on the application of new technologies, materials, or the improvement of design methods. However, despite significant achievements in this area, the issue of automating the processes of asphalt concrete mixture production management remains insufficiently researched and implemented. Based on the experience accumulated in Russia, the authors propose developing a system of adaptive control for the asphalt concrete mixture recipe, which contributes to the stabilization and improvement of production quality. In the article, the authors present the structure of the control system and its algorithms, as well as describe the results of modeling and evaluating the effectiveness of this system. The study shows that the adaptive control system for the asphalt concrete mixture recipe, developed based on the experience from Russia, successfully demonstrates its effectiveness in the conditions of Vietnam.

Keywords: asphalt concrete, asphalt concrete mix, Marshall stability, control system, formulation, simulation model, modeling, MATLAB, management efficiency

The work is devoted to the problem of providing electrical energy to remote production enterprises in the absence of a centralized power supply. The purpose of the work is to develop decision support tools for choosing autonomous power generation projects from a large number of possible alternatives. To achieve this purpose, a hierarchy of criteria was constructed and a comparative analysis of existing technical and economic solutions in the field of small-scale autonomous energy was carried out. It is shown that when choosing a power generation project for a particular enterprise, there is a fairly large number of alternatives, which makes the use of commonly used decision support procedures based on the hierarchy analysis method/analytical network method (in the classical version) ineffective. An iterative procedure with dynamic changes in feedback between criteria and alternatives is proposed, which makes it possible to reduce the dimension of the supermatrix during the calculation process and, thereby, reduce the time complexity of the algorithms. The effectiveness of the proposed modification of the analytical network method is confirmed by calculations. The constructed procedure for selecting an autonomous power generation project makes it possible to increase the level of scientific validity of technical and economic decisions when expanding the production activities of small enterprises in remote and sparsely populated areas.

Keywords: autonomous power system, decision support, analytical network method

The article discusses the use of a recurrent neural network in the problem of forecasting pollutants in the air based on actual data in the form of a time series. A description of the network architecture, the training method used, and the method for generating training and testing data is provided. During training, a data set consisting of 126 measurements of various components was used. As a result, the quality of the conclusions of the resulting model was assessed and the averaged coefficients of the MSE metric were calculated.

Keywords: air pollution, forecasting, neural networks, machine learning, recurrent network, time series analysis

A semi-Markov stationary model of operation of measuring instruments installed on complex technical systems is developed, which allows modelling the process of metrological maintenance of measuring instruments at combined verification and operational automated condition control. The results of modelling are presented.

Keywords: semi-Markov model, measuring instrument, verification, operational automated state control

The paper presents an ordinary and dynamic piecewise linear Leontief model with nonlinear predictors for the gross domestic product of Russia. The following variables are used as independent variables: the number of able-bodied population, retail trade turnover, and capital investment. In the right part of the model, along with the current value of investment volume, its lagged values with a lag of one and two years are included. The average relative error of approximation of each model and the values of the vector of triggers of independent variables were calculated.

Keywords: Leontief model, nonlinear predictors, gross domestic product, least modulus method, average relative approximation error, vector of triggers, linear-Boolean programming problem

Using numerical modeling, a study of heat transfer and hydrodynamics in plate heat exchangers with corrugated fins was carried out, while the height of the corrugation profile varied from 2 to 4 mm. The influence of profile height on heat flow and pressure drop was studied. It was revealed that an increase in the profile height leads to an increase in heat flow up to 34.05% and pressure drop up to 54.54%.

Keywords: corrugated heat exchanger, cooling system, microelectronics, profile height, heat flow, pressure drop, heat transfer, hydrodynamics, calculation, numerical modeling

Asphalt concrete mixes are the primary construction material for road surfaces, and precise design of their composition plays a key role in the quality and durability of road pavements. This article discusses the challenges associated with designing asphalt concrete mix compositions and presents a developed system for automatic mix selection. The automatic asphalt concrete mix composition selection system is a powerful tool for optimizing the material selection process used in road construction. This system can calculate the optimal mix composition, taking into account technical and economic constraints, leading to increased accuracy and reliability in mix selection. The advantages of this system include reducing the time and cost of the selection process, enabling testing and analysis of various mix options, ultimately improving the quality and durability of road pavements.

Keywords: asphalt concrete, asphalt concrete mix, composition selection, least squares method, linear programming method, software, automation, Python, Microsoft Access

The problem of choosing the most optimal gas supply scheme for rural settlements with a complex configuration and natural water barriers is considered using the example of x. Shebalino, Oktyabrsky district, Volgograd region. Four options for gas supply schemes with different numbers and locations of gas reduction points have been developed. The material characteristics and projected cost of design, construction and installation work for each option have been determined. Recommendations on the application of selection criteria are given.

Keywords: gas distribution network, gas reduction points, hydraulic regime, normalized pressure, cost, construction and installation works

The paper describes the process of modeling 3D structures of synthetic gas burners, with the analysis of the simulation results obtained for several types of models and the selection of optimal modes for them. The main use of the burner is planned for boiler equipment for household needs in private as well as apartment buildings, in the absence of central heating. In addition, the article provides a justification for the thermal parameters at the inlet and outlet of the burner.

Keywords: synthesis gas, combustion, design parameters, combustion chamber, nozzle, modeling

Radon is a chemically inert radioactive gas with daughter decay products (DPR) in the form of alpha particles. Radon flux density studies were conducted in the Komarovo residential complex in the Sovetsky district of Volgograd in April 2024 on an area of approximately 0.3 km2. The purpose of the study was to study the radon flux density on a land plot in the Komarovo residential complex (Sovetsky district, Volgograd) in April 2024. Research objectives: 1. Measurement of the radon flux density level at the study points. 2. Statistical processing of the obtained results. 3. Forecasting of radon hazard of a land plot in the residential complex "Komarovo". Research methods and equipment. The method of measuring the radon flux density from the ground surface using Alfarad-Plus (Russia) was used. The authors found an excess of the average values of the radon flux density in the Komarovo residential complex by 5 times compared with the data of the standard values of the radon flux (80 MBq/m2*s). Moreover, spot emissions of radon gas of abnormal values reaching 3945 MBq/m2*s were recorded in the studied area, and in the southwestern part of the residential complex there is a zone with the highest values of PP> 80 MBq/m2*s. There is no anthropogenic factor in the form of radioactive contamination. These facts indicate signs of natural radon pollution of the land and problems of environmental safety of the urbanized territory, which requires operational engineering and environmental measures to develop protective measures against radon danger in the residential complex "Komarovo".

Keywords: radon, radon flux density, radioactive contamination, radon hazard, radon risks, daughter products of radon decay, alpha particles, urban areas, residential complexes, lung cancer

This article highlights the theoretical results of analytical research in the field of the use of tethered balloons as carriers of barrier networks, which can be used as passive protection of particularly important civil and industrial facilities from unmanned aerial vehicles and other low-flying means of air attack. A diagram of an aerostatic barrier system, theoretically capable of countering air attack means, is presented. The elements of the methodology for determining the probability of damage to aircraft from cable type air barriers are presented.

Keywords: aerostatic air barrier system, unmanned aerial vehicles, tethered balloons, aerial protection of ground objects

This paper explores in detail the technological evolution and current state of question and answer (Q&A) systems. Using an example of an airline customer service task, a BERT-based model is developed that is capable of recognising user intentions and extracting named entities. The paper provides a detailed description of the dataset preparation, data analysis methods and data exploration techniques of the project. A description of the model and parameter settings during the model tuning process and the model training process is presented. The model developed in this project is named RNEEMAviCS-BERT, which achieved an intent recognition accuracy of 98.2% and named entity recognition accuracy of 83%. We have created a semantic analysis module for the question and answer system. The next stage of our work will be to integrate the dataset to complete the query-response and response generation components of the Q&A system.

Keywords: question-answering systems, ChatGPT, BERT, machine learning, neural networks, pre-trained models, intention recognition, named entity recognition, data analysis, model training

Technological pipelines of compressor stations are one of the significant types of basic equipment that ensures uninterrupted operation during gas transportation. In this article, we paid special attention to the issue of safe operation of the pipeline strapping of the gas treatment plant for transportation, which is designed to dry gas to the required parameters required by consumers and is one of the main technological units of the compressor station. During the operation of the adsorber lines with "hot" and "cold" gases, the pipelines of the regeneration line are subjected to high variable temperature loads. Thus, the operating organization faces the problem of ensuring sufficient compensation for the linear expansion of technological pipelines during their periodic heating. The calculation of the service life of the piping and its stability with a matched axial bellows compensator has been performed. Various solutions to the reliability problems of these compressor station components are considered and analyzed. It is concluded that it is necessary to update the regulatory design framework and introduce continuous technical monitoring methods into the operated facilities.

Keywords: gas treatment plant, process pipeline, adsorber, safe operation period, temperature load, compensator