Visnik of the Volodymyr Dahl East Ukrainian National University

Research on the influence of spark ignition energy on the detonation initiation process in a detonation tube

2025-10-21T13:29:18+00:00

The paper examines the impact of spark ignition energy on the detonation initiation process in a detonation tube for a powderless mortar with controlled shot energy. It is shown that successful tests have demonstrated the ability of mortar prototypes to launch shells without the use of traditional powder charges, which confirms the effectiveness of the developed launch technology. The system is designed for automatic loading and provides the ability to fire with direct fire. Unlike conventional mortars, the proposed system uses a gas detonation charge to regulate the firing range. Therefore, the range of the shell is controlled not by changing the mortar elevation angle, but by changing the shot energy while maintaining a fixed elevation angle. Replacing the powder charge with a combustible gas mixture contributes to the integration of the mortar shot control system into broader fire control systems. This allows you to create a new semi-direct fire mode, which improves the tactical deployment of weapons in combat conditions. To transfer this technology to military production, further research and development of a specialized mortar control system are necessary. The key parameters for controlling the energy of a mortar shot are the initial pressure and volume of the compressed gas charge in the gas detonation chamber. The results of experimental studies revealed the influence of the spark ignition energy on the process of initiating detonation in the detonation tube. The study was conducted for 3 ranges of values of the total energy of the spark discharge, which were equal to 50 mJ, 0.84-1.54 J, 13-14 J. The spread in the values of the total energy of the discharge is associated with the deviation of the voltage of the spark gap breakdown. At each of the values, measurements were carried out no less than 3 times. It was established that an increase in the discharge energy leads to a reduction in the distance and time of the transition of combustion to detonation. In particular, in a detonation tube with an internal diameter of 73 mm, filled with a stoichiometric mixture of technical propane-butane with oxygen, the time for the transition from combustion to detonation was reduced from over 1200 μs to about 200-300 μs in the event of an increase in the total energy of the spark discharge from 50 mJ to 13-14 J. At the same time, the distance from the transition from combustion to detonation was reduced from 299-413 mm to 185 mm.

Formation of an information base for automated control of the well drilling process

2025-10-21T11:15:21+00:00

A method of information support for automated control of the process of drilling wells in iron-bearing rocks based on electromagnetic eddy current conversion of sensing signals is proposed. When modeling the dependence of the eddy current sensor parameters on the characteristics of the medium under study, we used its transformer model in the form of two coils with air cores located at a certain distance above each other. The transformer model of the eddy current sensor adequately reflects the processes that occur in it when the electrical conductivity and magnetic permeability of the sample under study change. The primary circuit of the transformer model represents the measuring coil of the sensor. The test medium forms the secondary circuit of the transformer model. The impedance of the measuring coil depends on the physical, chemical, and textural properties of the medium under test, as well as on the operating frequency of the sensor current source. The real part of the impedance is determined by the resistance of the circuit in which eddy currents flow. The sensor impedance and the spectral characteristic of the measured signal can be used to evaluate the characteristics of the medium under study. The experimental platform and combined electromagnetic transducer were used to test the approach. The combined probe is placed above the medium in which the ultrasonic signal and eddy current signal are simultaneously excited and received. Modeling of the parameters of the combined probe allowed us to determine and formalize the relationship between the parameters of the measuring coil of the probe and the characteristics of the medium under study. The analysis has shown that the use of eddy-current transformation parameters in combination with ultrasonic measurements improves the results of recognizing the main mineralogical and technological types of iron-bearing ores of the operated deposit. The obtained results make it possible to increase the efficiency of automated control of the well drilling process in the extraction of iron ores using information on the physical and mechanical characteristics and geological structure of the drilled rock.

Мodeling the dynamics of the overflow product in fine wet screening of iron ore

2025-10-21T11:34:55+00:00

Screening or sifting is widely used in the mining industry to separate ore particles by size. Huge volumes of ore at mining enterprises are regularly subjected to industrial screening, so studying the kinetics of the process and optimizing the corresponding technology is of great economic importance. Solving this problem is complicated by the presence of many working variables and various disturbing factors that determine the results of this technological operation. Firstly, these include the complex distribution of ore particles by size and density, as well as the complex influence on the movement of the oversize product of various dynamic operating modes of the screening surface. Recently, fine wet screening screens have been increasingly used for the classification of crushed ore at enrichment enterprises. The use of wet material for screening, the solid phase of which includes ore particles of different densities and sizes, imposes additional requirements on the design and adjustment of the corresponding working equipment. During continuous screening, when the feed rate of ore material to the screen is high enough, and it creates a concentrated layer of particles of a certain thickness, for example, around the feed section, only the particles in the layer that are in direct contact with the screen have a chance to pass through the openings. As long as the upper layers are able to add small particles to this contact layer, the material flow rate will remain constant. As the material moves along the screen and more and more smaller particles pass through the holes, it becomes more dispersed. At the same time, the particles become more mobile and “separated,” transitioning from a “clumped” state to “separated” motion. These features significantly complicate the task of forming effective automated control of this process. The model of the dynamics of crushed ore material on the screening surface of a vibrating screen was studied, taking into account the advection, diffusion, segregation, and percolation of its particles in the material layer. The approach used allows taking into account the transformation of the particle size distribution of the solid phase of the oversize product and its density during movement on the screen surface. This improves the quality of automated control of the process.

Development of a comprehensive information system for apiary management

2025-10-21T13:03:10+00:00

The article presents the concept of developing a comprehensive information system for efficient management of an industrial apiary under modern economic and environmental challenges. The relevance of the development is driven by the growing need for digitalization in beekeeping both in Ukraine, which is one of the leaders in honey exports, and globally, where active integration of IT technologies into agricultural production is taking place. The structure and functional modules of the system are described, covering key areas of beekeeping such as the accounting of quantitative and qualitative characteristics of bee colonies, monitoring their physiological state, planning technological operations, controlling honey collection, and analyzing expenditures. The main goal of the development is to optimize management processes, reduce labor intensity, and minimize risks by implementing modern IT solutions. A detailed analysis of problems affecting apiary productivity is carried out, taking into account biological, climatic, veterinary, and organizational aspects. A modular approach to system design is proposed, enabling forecasting of colony development and identification of potential threats based on the integration of large volumes of heterogeneous data. Particular attention is paid to the application of fuzzy logic as a tool for formalizing the expert experience and intuitive knowledge of beekeepers, which makes it possible to generate quantitative recommendations based on qualitative assessments. Examples of fuzzy rule applications are demonstrated for assessing colony strength, brood condition, swarming prediction, pesticide poisoning risk management, and disease diagnosis. It is shown that the developed system has the potential to integrate with IoT devices, sensor networks, and mobile applications for real-time data acquisition, opening opportunities for creating an intelligent decision support platform in industrial beekeeping to enhance productivity, economic efficiency, and production sustainability in a changing environment. The conclusions state that implementing such a system can significantly increase the profitability of apiary operations and reduce the impact of the human factor on critical production processes.

Algorithm for identifying objects managed by second-order links with delay time

2025-10-21T13:13:27+00:00

The object of research is the optimal parameters for regulator adjustment and the quality indicators of transient processes.

The current problem is that modern technological processes are complex control objects. Therefore, when designing automation systems, the tasks of identifying the control object, calculating the regulator parameters, and their further optimization become particularly important. Optimal settings ensure the highest possible product quality and reduce its cost at a given production volume. Direct determination of controller parameters through experiments on a real object can lead to a loss of finished product quality and damage to raw materials and catalysts. To avoid these risks, the calculation algorithm was implemented in the Maple software package environment.

The study developed and tested an algorithm for identifying control objects with different characteristics of transient processes, described by second-order links, taking into account the delay time. Based on the obtained transfer functions of equivalent objects, P-, PI-, and PID-controllers (proportional, proportional-integral, and proportional-integral-derivative) were tuned. The parameters were determined using the triangle method, the method of undamped oscillations (Nicholas–Ziegler), and the proposed algorithm. The results obtained are intended for use in automatic control systems.

A comparative analysis of the quality of transient processes in systems tuned using different methods was performed. It was found that the parameters obtained using the new algorithm significantly improve the dynamic characteristics of the system (reduction of overshoot, control time, static and dynamic errors). In addition, an algorithm for searching for controller parameters taking into account the overshoot limitation was proposed, which also showed positive results. The identification error does not exceed 3%, which is acceptable for calculations of this type.

Аpplication of additive technologies to restore and strengthen relevant parts of printing equipment

2025-10-21T11:00:11+00:00

The article is devoted to the study of the potential application of additive technologies for the restoration and reinforcement of critical components of printing equipment. The authors analyze the effectiveness of 3D printing methods in ensuring technical reliability and accelerating repair processes. The relevance of the research is driven by the growing demand for flexible, rapid, and cost-effective solutions for restoring worn-out or unavailable parts in the printing industry. Under conditions of intensive machine operation and the absence of necessary spare parts in stock, the implementation of additive manufacturing helps minimize downtime, avoid prolonged production cycles associated with traditional casting or machining, and enhance the overall resilience of production processes. The aim of the research is to justify the effectiveness of additive manufacturing technologies for producing replacement parts for printing machines with high requirements for geometric accuracy, mechanical strength, and wear resistance, as well as to develop practical recommendations for their application. The study employed an experimental methodology that involved the fabrication of test samples from composite polymers and polyamide powder using FDM and SLS technologies. Mechanical tests for bending strength, wear resistance, and vibration durability were conducted, along with a metrological analysis of dimensional accuracy. As a result, it was established that FDM printing using composite materials allows for weight reduction of parts by up to 20% while maintaining strength comparable to traditional metal counterparts. SLS technology provides high precision (up to ±0.05 mm) and dimensional stability for components of complex geometry. The study also demonstrated that the use of advanced technologies such as Arburg Plastic Freeforming (AKF) expands the possibilities of using standard industrial granulates in 3D printing, significantly reducing material costs. Prospects for further research include improving quality standards for additive manufacturing of printing components, developing new heat-resistant composites, and implementing digital libraries of part models in the maintenance systems of printing equipment.

Features of synthesis of optimal cam profiles for gas distribution mechanisms of transport vehicles

2025-10-21T13:54:40+00:00

The article discusses the features of synthesizing optimal cam profiles for gas distribution mechanisms in vehicles, which play a key role in ensuring the efficiency, reliability, and environmental friendliness of power plants. The relevance of improving the design of internal combustion engines in the context of growing demands for resource conservation and reduction of operating costs is emphasized. It is shown that traditional methods of designing cam profiles do not fully take into account the complex relationships between the kinematic and dynamic characteristics of the valve mechanism, which leads to increased wear, noise, vibration, and reduced fuel efficiency.

A new methodology for synthesizing optimal cam profiles is proposed, based on the use of generalized mathematical models and methods of mathematical experiment planning. This allows the formation of optimal parameters for the accelerations of the tappet in different sections of its movement, taking into account the restrictions on the radius of curvature of the profile, contact stresses, the valve spring reserve coefficient, and the conditions for ensuring the continuous dynamics of the mechanism. The implementation of second-order mathematical plans made it possible to construct nomograms for determining the optimal parameters that ensure an increase in the completeness coefficient of the tappet lift diagram and a reduction in dynamic loads.

The results obtained prove that optimization of cam profiles contributes to reducing loads on gas distribution mechanism components, increasing its service life and reliability, as well as improving gas exchange processes in engine cylinders. This ensures an increase in power, fuel efficiency, and environmental performance of transport power plants. The developed approach is of practical importance both for the creation of new engines and for the modernization of existing designs, corresponding to current trends in the development of transport technologies.

The results of the study open up prospects for further automation of gas distribution mechanism design and integration of computer modeling into engineering practice. This allows for the creation of innovative solutions in the field of engine building, aimed at achieving high performance and durability of transport systems.

Еfficiency of wind power plant with aerodynamic multiplication tg-750 according to the results of experimental operation

2025-10-21T11:09:15+00:00

The article indicates the need to improve the efficiency of converting wind energy into electrical energy. Information is provided that the mechanical multiplier ranks second in terms of unreliability among the equipment of a wind power plant. Due to the need for routine maintenance, oil replacement, poor environmental and noise characteristics, developers are looking for alternative options. It is indicated that low-speed generators, despite extensive operating experience, have poor weight-and-dimensions. An alternative and promising solution is the use of aerodynamic multiplication. A comparison of wind power plants with aerodynamic multiplication with plants based on a low-speed generator allows us to conclude that they have better weight-and-dimensions. Historical information is provided on the development and study of wind power plants with aerodynamic multiplication. The principle of operation of wind power plants with aerodynamic multiplication is described and an explanation is given of how the generator speed is matched. Historical errors in assessing the efficiency of aerodynamic multiplication based on the Betz criterion are presented. It is shown that Golubenko M.S. and his followers proved that the efficiency of aerodynamic multiplication does not depend on the primary wind turbine, but is determined only by the parameters of the secondary wind turbine. The efficiency is calculated as the ratio of the power coefficient of the secondary wind turbine to its braking coefficient. The theoretical value of the efficiency of the TG-750 plant, which Golubenko M.S. obtained at the design stage, is given. According to the data obtained during the experimental operation of the TG-750 wind power plant, graphs of the dependences of the power coefficient of the primary and secondary wind turbines and their braking coefficients are constructed. The dependence of the efficiency of aerodynamic multiplication on speed was calculated and the results obtained were compared with theoretical values. The real efficiency turned out to be somewhat lower than the theoretical one, which is explained by the presence in the installation, in addition to aerodynamic processes, of purely mechanical ones - friction, vibration, etc. The efficiency of converting wind energy into electricity in installations with aerodynamic multiplication is higher than in classical wind turbines. Conclusions were drawn about the confirmation of the theoretical results by the results obtained in the process of experimental operation of the TG-750 and the prospects for studying and implementing installations of this type.

SAC-based reinforcement learning agent for automated network penetration testing

2025-10-21T09:53:13+00:00

Cybersecurity threats and cybercrime damage continue to escalate annually. Projections indicate that total damages will reach $10.5 trillion by the end of 2025, representing a 3.5-fold increase from the cybersecurity damages recorded in 2015. With the rise of AI adoption by malicious actors, there is an increasing need for defensive tools that also leverage AI capabilities.

This paper continues the research trend of applying reinforcement learning to penetration testing for identifying security vulnerabilities in computer networks. To achieve this objective, the Network Attack Simulator (NASim) is employed as a testing environment. NASim is a simulator designed for evaluating automated penetration testing through reinforcement learning, built on the Gymnasium framework.

This paper presents a hybrid reinforcement learning algorithm specifically, which combines the Soft Actor-Critic (SAC) architecture with discrete action spaces, thereby enabling the SAC algorithm to operate effectively within environment.

The algorithm underwent evaluation using the nasim:Small-v0 scenario. Experimental results demonstrate that the proposed method achieves several noteworthy performance metrics. First, the algorithm exhibits stable convergence behavior throughout the training process, indicating robust learning dynamics. Second, the method demonstrates exceptional efficiency in system compromise, requiring an average of 8.63 steps during late training episodes to fully compromise target systems. Third, the algorithm maintains a perfect 100% success rate during the evaluation phase, demonstrating reliable and consistent performance.

Additionally, the algorithm achieves an average reward of 184.61 in later training stages, indicating strong performance for potential cybersecurity applications. However, these results require extensive training time, with potentially even longer training periods needed for more complex scenarios. This creates a trade-off between computational efficiency and performance quality that must be considered for practical implementation.

Design of the information system of the admission committee of a higher educational institution

2025-10-21T10:04:05+00:00

The paper discusses the design of information system to automate work with documents of applicants in the admissions office of a higher education institution during the admission campaign. The developed information system is a web application which is focused on employees responsible for receiving physical documents, such as registrars, operators and officials who control the admission process. The main goal of the designed system is to ensure quick and convenient entry of data about applicants at the time of submitting documents. Applicants are added to the system based on an existing database, which allows you to avoid re-entering personal data and minimize possible errors. A key feature of the designed system is the implementation of data mining tools, which will relieve employees of routine tasks of document verification, allowing them to focus on solving truly complex and non-standard situations. To achieve the main goal, a set of tasks was solved. In particular, the shortcomings of the traditional approach to processing documents of applicants in higher education institutions were analyzed. The feasibility of implementing an information and analytical system for centralized storage and automation of application processing is substantiated. Functional models of the designed AS-IS and TO-BE system are presented. The architecture of an improved information system is proposed and separate software modules are developed for importing input data and automatically classifying applicants' cases by the completeness of documents with subsequent integration into a fully functional admission campaign support system. The proposed architecture is based on a relational database model, client-server structure and classification algorithms. The software is developed using the Python programming language, pandas, tkinter, mysql.connector libraries. MySQL Workbench was used for database modeling, and development was carried out in the PyCharm environment. The effectiveness of the approach is demonstrated on test sets, and a comparison is made with the real actions of admissions committees. The system is ready for further integration and scaling.

Automated construction of a risk register in software development based on issue tracking in GitHub projects

2025-10-21T10:22:33+00:00

The article discusses the topical problem of automating the process of building a risk register in software development based on the analysis of issue tracking data in GitHub Projects. In the context of the increasing complexity of software products and the high dynamics of changes in the life cycle of IT projects, traditional manual approaches to risk identification are increasingly losing their effectiveness due to delays in updating information and significant human costs. The author proposes the concept and implements a prototype of a Python script that provides automated extraction, pre-processing, multi-level classification and the formation of a structured risk register, which allows integrating this process directly into the usual life cycle of project quality management. The proposed approach is based on the classification of risks according to a defined taxonomy, covering seven main types: engineering, environmental, process, constraint-related, security, behavioral and external risks. For each risk group, a list of relevant keywords and text indicators is defined, which ensures the effective operation of the keyword matching algorithm in combination with the analysis of labels, comments and task status. As part of the trial, the script was tested on an artificially formed dataset containing more than 150 issues with a variety of texts close to the real practice of open projects. An important feature of the prototype is the possibility of multiclass classification, when one task can simultaneously correspond to several risk groups, which adequately reflects the interdisciplinarity of modern problems in the field of software development. The efficiency of the script is ensured by high performance: the average processing time for a full array of data does not exceed 1.5 seconds, which allows you to integrate the solution into regular CI/CD pipelines through GitHub Actions. The article also outlines the methodological basis for predicting the effectiveness of the developed approach using data from modern research, in particular the results of the BEACon-TD model, which demonstrated an F1 measure of more than 0.81–0.86 on real issue tracking sets. This allows you to analytically predict the potential accuracy of the proposed approach at the level of 80-85% with proper additional training and adaptation of keywords to the specifics of the project. The proposed solution allows not only to identify problem areas at the early stages, but also to form the basis for further predictive analytics on the impact of risks on the time, financial and qualitative parameters of development. In addition, the script creates a structured ledger in JSON and Excel formats with customized design and provides visualization of the distribution of risk types using diagrams in Matplotlib, which increases the transparency and usability of the analysis results. The obtained data can be integrated into quality management systems or transferred to stakeholders for timely decision-making. As a result, it is proved that the proposed automated construction of a risk register based on GitHub Projects is a promising direction for improving the processes of software quality management and technical debt management, and the developed prototype demonstrates an example of the practical implementation of this concept in combination with agile and DevOps approaches.