Bulletin of L.N. Gumilyov Eurasian National University Technical Science and Technology Series

Shear Buckling Behaviour of Cold-Formed Steel Members With Web Openings

2025-12-08T13:49:16+00:00

Cold-formed steel (CFS) sections have become a common choice in
modern construction because they offer considerable strength while remaining lightweight and straightforward to install. When openings are cut into the web to accommodate building services, however, the way these members carry shear can change substantially. In this work, the behaviour of channel sections containing such openings is examined in detail. A series of nonlinear Finite Element (FE) simulations was created, each including the influence of initial geometric imperfections, and the numerical responses were compared with available test data to ensure they reflected physical behaviour. After validation, the models were used to study how different variables, including the shape of the opening, its size, and the slenderness of the web, affect shear resistance. The numerical results indicate a sharp drop in capacity when the openings become large or when the web is relatively thin, with the most severe cases showing reductions approaching 90% for opening size and roughly one-third for web slenderness.

Problems and Solutions in the Operation of a Car Ball Joint

2024-11-06T11:32:08+00:00

The article presents the signs of ball joint malfunction. During vehicle operation, this component absorbs any impact from the road surface, meaning that under operating conditions it is subjected to heavy loads. The authors propose extending the service life of the ball joint by using an innovative repair kit designed for reciprocating rotational motion. The study shows the results of stabilization, wear mode, and wear uniformity. In reciprocating rotational motion of the shaft or outer ring, this is achieved by twisting the spring insert. Accordingly, braking occurs on the inner or outer surface of the spring insert (ratchet effect), and it is forced to rotate only in one direction depending on the winding direction of the spring. During operation, the frictional contact surfaces change, which helps reduce their wear. To meet these conditions, a design of sliding bearings for rotational motion has been proposed, in which these requirements can be implemented. For this purpose, the bearing is equipped with a movable spring insert in the form of a helical cylindrical spring (an intermediate element), which in oscillatory mode is forced to rotate only in one direction, thereby ensuring uniform wear.

Study of the structure of hydration products of cement stone with hyperplasticizer and silica microfillers

2025-05-15T17:21:07+00:00

In this paper, the combined effect of active silica fillers of technogenic and natural origin and polycarboxylate superplasticizer on the structure of the cement matrix was investigated in order to increase its microporosity. It was found that the dispersion of filler particles, the amorphization of the structure and components, are due to the effect of chemical energy on the molecular and surface crystallization structure of binder particles. Studies on the combined introduction of silica and plasticizer in the composition of mortar mixtures make it possible to increase the content of the pozzolanic additive to 15% of the binder weight, which helps to reduce cement consumption, while simultaneously optimizing the microstructure of the cement stone and further obtaining concrete with high construction and technical characteristics. As part of the study, a detailed microstructural study of the cement stone was carried out to analyze the hydration products in the

Optimization of advertising budget allocation in the agro-industrial complex based on a machine learning algorithm

2025-11-13T07:12:27+00:00

The study is aimed at using the NSGA-III algorithm for multi-criteria optimization based on machine learning to solve marketing and advertising problems in the agro-industrial complex (AIC). In the context of increasing competitiveness and digitalization of the economy of
the Republic of Kazakhstan, the relevance of the work is due to the need to optimize the distribution of marketing budgets of enterprises, taking into account such criteria as the effectiveness of advertising campaigns, coverage of the target audience and cost reduction. The methodology used in the work involves formalization of objective functions, constraints and the use of NSGA-III to find Pareto-optimal solutions. The results obtained during cybernetic modeling usually indicate high quality of solutions (hyper-volumetric), a compromise between the criteria and the dominant role of digital channels (up to 15% increase in the budget). The data obtained during the study confirm the potential use of NSGA-III for marketing planning tasks in the agro industrial complex and can serve as a basis for making management decisions at agro-industrial enterprises. The results of the study prove that the NSGA-III algorithm has significant potential in improving marketing planning processes in the agro-industrial complex and supporting management decisions of enterprises. This approach allows for efficient use of resources in the agribusiness sector and increased competitiveness in the market.

Intermodal transportation: essence and significance

2025-12-01T13:56:40+00:00

This scientific review article analyzes the essence and significance of intermodal transportation of agricultural products in Kazakhstan. The study will focus on the practice of combined use of several modes of transport (rail, road, sea) in the supply of grain and other agricultural products in Kazakhstan. The article identifies the current state of intermodal transportation in agricultural logistics in Kazakhstan, the main features and problems, and describes the place of international experience in their solution. As a result of the study, it was shown that the development of intermodal systems increases the efficiency of transportation of

Exploring the possibility of using the WAAM platform for 3D printing of cylindrical parts with minimal investment

2025-10-14T07:09:55+00:00

Wire Arc Additive Manufacturing (WAAM) is an additive manufacturing technology for metals based on the arc welding process, which allows metal parts to be formed in layers by melting a wire electrode. The vast majority of modern studies use a robotic welding system. This study investigated the possibility of manufacturing cylindrical parts using a WAAM system based on a low-investment and simple configuration. The device implemented a combination of a rotary table and a vertical Z-axis motion module. The casting process was performed using the GMAW (Gas Metal Arc Welding) method. Common low-carbon steel ER70S-6 was used as the wire electrode, and 100% argon was used as the shielding gas. A cylindrical part was cut out, and after grinding and polishing, a microstructural analysis was performed under a microscope. In the
microstructure, the grains are distributed in a fine isotropic form, and no defects or traces of oxidation were observed at the interlayer boundaries. This showed uniform heat distribution and the correct choice of protective environment. The results obtained prove that high-quality metal components can be created using a simple WAAM system and that this method can be an affordable solution for small-scale production and laboratories.

Green areas on highways and streets: a comprehensive study of the benefits and challenges of implementing vegetation on roadways

2025-11-13T16:04:57+00:00

With the rapid expansion of urban areas, roadside green infrastructure has become a critical element of sustainable urban planning. While green areas along highways and streets occupy a relatively small share of
the urban carbon sink, they provide disproportionate ecological and social
benefits, including improved air quality, carbon sequestration, effective stormwater management, heat island mitigation, and support for biodiversity. This study employs a qualitative comparative case study approach, drawing on literature and policy analysis from Kyoto (Japan), Hangzhou (China), and Riyadh (Saudi Arabia), to evaluate how differing climatic and urban contexts shape the design, performance, and challenges of roadside vegetation. The findings highlight that canopy type, planting methodology, and policy frameworks have a strong influence on the effectiveness of RGI, particularly in regulating temperature, controlling pollution, and supporting ecological
connectivity. However, the study also identifies common challenges across
contexts, such as spatial constraints, high maintenance demands, and
vulnerability to climate extremes. Addressing these issues requires integrated strategies that combine ecological design, long-term governance, and context specific policies. The paper concludes by emphasizing that effective roadside greening can enhance urban resilience, provided it is supported by informed planning and sustained management.

Сomparative analysis of pressure distribution of compression piston rings in an internal combustion engine cylinder

2025-07-10T11:34:33+00:00

The article presents a comparative analysis of the specific pressure exerted on the cylinder wall by a traditional compression piston ring and an alternative design consisting of two half-rings. The study focuses on the theoretical aspects of the formation and distribution of contact pressure between the piston ring and the cylinder wall. Mathematical models describing the stress-strain state of the ring when installed in the cylinder are provided, along with a simplified
approach to calculating pressure for the two half-ring design without considering material elasticity. The calculations revealed that the traditional solid ring produces a non-uniform pressure diagram with peak values, which may contribute to accelerated wear of cylinder-piston
group (CPG) components. In contrast, the pressure distribution generated by the two half-ring configuration is uniform, ensuring consistent load on the cylinder wall and reducing localized overloads, friction, and thermal deformations. The graphical dependencies and Fourier series approximations confirm the model’s agreement with real-world operating conditions. The paper also offers recommendations for selecting ring materials and geometric parameters to improve combustion chamber sealing and extend engine life. The authors emphasize that the implementation of a two half-ring configuration represents a promising direction for the modernization of piston rings in internal combustion engines, particularly under conditions of
increased temperature and mechanical stress. The findings of this study may be of interest to engineers, researchers, and developers involved in the design and analysis of CPG components.

Semiotics of space in ecological agroarchitecture

2025-11-13T16:16:52+00:00

In the context of worsening environmental problems, modern
architecture is turning to the search for new models of interaction with nature. Ecological agroarchitecture, combining sustainable design, agrotechnology and the philosophy of nature-oriented thinking, is becoming one of the relevant areas. The purpose of this study is to consider the architectural space of the agroecological type as a semiotic system capable of translating the values of sustainability, memory and cultural identity. The work focuses on objects where the principles of bioesthetics, environmental ethics and symbolic expression intersect, such as energy – intensive buildings, memorial complexes and biomorphic pavilions. The methodology is based on an interdisciplinary approach combining architectural semiotics, environmental design and cultural and philosophical analysis. The results show that architectural forms of agroarchitecture have symbolic potential: they visualize natural processes and convey the ideas of cyclicity, rebirth and belonging.

The research contributes to the development of the concept of architectural space as a meaningful system and can be applied in the design of objects integrated into the ecological and cultural context.

Using Python programs to process data from unmanned aerial vehicles for forest fire monitoring

2025-11-14T12:48:47+00:00

Modern challenges to environmental safety require the integration of engineering and information technologies to quickly respond to threats such as forest fires. One promising area is the use of unmanned aerial vehicles (UAVs) in combination with geographic information systems
(GIS) and data mining software. In this paper, we consider a project to create a software solution implemented in Python for monitoring and predicting the spread of forest fires. 3,000 hectares of woodlands divided into sectors were used as a conditional landfill. Each sector was analyzed based on weather data (temperature, humidity, wind speed), vegetation density, and fire hazard index calculations. The libraries Folium (for interactive mapping), Pandas (for tabular data processing) and Matplotlib (for visualization) were used for implementation. Three drones (multispectral camera, thermal imager, RGB camera), equipped with various sensors, worked on a schedule, providing continuous monitoring based on charging time. The proposed architecture of the system makes it possible to adapt it to various geographical conditions and tasks. The results are presented in the form of graphs, heat maps and tables, which makes the system convenient for
operators and analysts. The work is relevant in the field of "Engineering and Technology" and reflects the synthesis of information and engineering solutions to environmental safety problems.

Analysis of the stress-strain state of gears by the finite element method in SolidWorks

2025-11-27T05:26:09+00:00

This study focuses on the evaluation of the stress-strain state of a spur cylindrical gear through numerical simulation using the finite element
method (FEM) implemented in SolidWorks Simulation. The main objective is to assess the gear’s strength under static loading, accounting for thermal conditions, and to identify zones of stress concentration. The research
encompasses both theoretical calculations and numerical modeling. A gear made of 40X alloy steel, modeled in 3D, was subjected to force loads and
appropriate boundary conditions. The results demonstrated that the maximum equivalent stresses remained well below the material's yield strength, and all deformations were within the elastic region. The findings also highlighted critical areas susceptible to local stress peaks. A comparison with analytical methods confirmed the higher precision of FEM in predicting stress distribution. The outcomes contribute to gear design optimization by enhancing reliability and fatigue resistance. The methodology and results have practical implications for improving the durability and performance of gear mechanisms in mechanical engineering applications.

Development of a Methodology for Optimizing Repair Intervals of Open-Pit Mining Equipment Units

2025-11-20T09:54:57+00:00

This article proposes a methodology for optimizing the maintenance intervals of mining equipment components, using the example of steering cylinders in CAT 16M and 16M3 motor graders operated by KazMinerals Bozshakol mining enterprise. The study is based on the analysis of actual production statistics from 2018 to 2025, including both scheduled and unscheduled repairs. Causes of failures and component operational resources were quantitatively assessed using MTBF (Mean Time Between Failures) and MTBS (Mean Time Between Services) indicators. The calculations identified two optimal maintenance intervals — 7000 and 12000 engine hours. These intervals are tailored to actual operating conditions and are aimed at preventing unexpected failures while making maintenance strategies more flexible and effective. The method allows for adaptive scheduling of maintenance activities, based on real-world operational data, and ensures more efficient utilization of equipment resources. Moreover, the proposed approach improves the reliability of production processes, reduces unnecessary expenses, and optimizes the overall maintenance workflow.

Comparative analysis of the small upper stages implementation schemes

2025-11-25T03:44:39+00:00

This article is devoted to a review of existing small upper stages, including
perspective upper stages under development or testing, actively used in the tasks of launching small spacecraft into target orbit, the relevance of which has recently been increasing against the background of the trend of miniaturization of spacecraft and, consequently, the reduction of
payload mass. The paper considers the main classification features of upper stages, including mass, type of propulsion system, design and layout schemes. In particular, the advantages and disadvantages of the above schemes are discussed in terms of layout flexibility, design weight,
manufacturability, ease of assembly, and operational reliability. A comparative analysis between them is given for such key parameters as thrust developed by the propulsion system, the mass of the payload to be launched to the target orbit, and the method of propellant supply. The peculiarities of the use of single-component and two-component fuel are also considered, as well as the influence of fuel pair selection on the efficiency and safety of the upper stage. The purpose of this study is to select and justify a scheme for the realization of a small upper stage combining optimal technical characteristics, high reliability, economic efficiency and environmental safety. The key element of scientific novelty is the application of a multi-criteria analysis method to evaluate various designs for small upper stages. This method allows formalizing and balancing conflicting engineering criteria, including mass efficiency, specific impulse, multiple firing capability, technological maturity, etc.

Enhancing the performance of forced-induction diesel engines by improving oil volume management in the lubrication system

2025-11-27T05:43:13+00:00

The relevance of this research is based on the need to find additional ways to improve the efficiency of using forced-induction engines in vehicles and to reduce the ongoing costs of their maintenance. The research aims to evaluate the general principles and patterns of how oil level in the engine affects oil aging and changes in the technical condition of the diesel engine. The study included an experimental assessment of how motor oil parameters change during the operation of a car engine. The results provided data that shows how various parameters, which characterize the performance of a forced-induction automotive diesel engine, depend on the oil fill capacity. The study also determined how the cost of improving the performance of a forced-induction automotive diesel engine relates to the frequency of oil changes during its operation. Furthermore, the paper describes the operating principle and proposes a design for a regulator of the oil level in the engine crankcase. The findings indicate a need to reconsider the current practice of changing the oil in the crankcase of automotive diesel engines every 2000 km. This is because, under this schedule, the specific operating costs of the engine are high and economically inefficient. The practical significance of the results lies in the ability to change the oil volume in the lubrication system during vehicle maintenance, as well as when a major overhaul or forced induction of diesel engines is required.

Study of the load on the teeth of the excavator bucket

2025-12-04T13:00:41+00:00

The article discusses the influence of the long and short teeth of the excavator bucket on the efficiency of work. It was studied based on the analysis of patent solutions and numerical modeling in SolidWorks Simulation. The relevance of the study has shown that it is associated with the importance of choosing the right tooth length, adapted to different types of soil. The purpose of the study is a comparative assessment of the strength characteristics of long and short teeth, the state of stress – deformation and resistance to penetration into the soil. As a methodology, it included the calculation of the anti-excavation resistance force, the analysis of patents from the United States, Europe, China and Russia, the creation of 3D models and static modeling in SolidWorks. In addition, the calculation was carried out. The main results showed that long teeth can increase their ability to penetrate dense soils, reducing the peak loads that arise in the scoop, but their bottom stresses are higher. Short teeth provide a smooth distribution of tension and last longer on medium or soft soil. The relevance of the study is reinforced by the fact that modern earthmoving machines operate in conditions of variable soil density, which requires universal solutions. Optimizing the length of the teeth allows you to reduce energy consumption, increase productivity and increase the resource of equipment. In this regard, recommendations have been made.

Problems of mechanical processing of parts from austenitic steel 110g13l

2025-12-08T12:54:48+00:00

This article presents an analysis of scientific studies devoted to the machining of 110G13L steel. It was identified that research focused on investigating and developing machining methods for 110G13L steel is practically absent. In industrial practice, cutting inserts from foreign manufacturers are predominantly used for machining this steel. Nevertheless, the problem of excessive cutting tool consumption due to rapid wear, chipping, and breakage remains unresolved and increases the production cost of components made from 110G13L steel. The results of the experimental study confirmed the feasibility of applying thermo-friction milling with pulsed cooling for machining 110G13L steel. When machining under optimal cutting conditions, the achieved surface roughness reached only Rz ≤ 10 μm. However, it was revealed that there is an issue related to ensuring the required surface quality and chip breaking during machining. It is proposed to develop a combined milling method for difficult-to-machine materials, where the cutting mechanism is based on both thermo-friction and conventional cutting. This research was funded by the Committee on Science of the Ministry of Science and Higher Education of the Republic of Kazakhstan under grant № AP26199283, “Development of a combined method for processing hard-to-machine materials”.

Automated extraction and structuring of menus from PDF files using machine learning and NLP techniques

2025-12-15T12:46:53+00:00

This study explores state-of-the-art approaches for processing PDF
documents, with a focus on analyzing poorly structured restaurant menus. The focus will be on analyzing poorly structured restaurant menus. Successful automated processing typically requires well-structured documents, meaning that aesthetic design must often be sacrificed for machine readability. However, in case of restaurants, the design of the menu is more valuable than its structure, that is why the menus are harder to process, due to its poor structure. With the ability to successfully process the poorly structured PDF documents, further processing of the documents from other spheres of businesses should become much easier. A comparative analysis is conducted of structural features in different types of PDF documents, including legislative acts and academic publications.

The research is aimed to use machine learning methods in order to overcome the challenges in automation of data extraction, analysis and structuring.
Solution that has been described in the study is developed to overcome the
problems with poorly structured PDF documents.