DOAS: The Diamond OA Standard Challenges and Issues of Modern Science (ISSN 3083-5704) is an interdisciplinary academic publication that publishes original research papers dedicated to cutting-edge advancements across various interconnected fields. The journal welcomes submissions encompassing all stages of the life cycle of innovative products within mechanical engineering, applied mechanics, materials science, aerospace engineering, electrical engineering, power engineering, and electronics — from conceptualization and design to realization, operation, and disposal. The aim is to enhance manufacturing processes, improve product quality, and ensure its resilience in contemporary production, considering the environmental impact, as well as economic, managerial, market, financial, and marketing strategies in conjunction with modern advancements in information technology, cybersecurity, automation, and robotics. The primary goal of the journal is to establish a platform for knowledge exchange between scientists and practitioners operating at the intersection of diverse disciplines, employing a comprehensive approach for analyzing challenges and synthesizing innovative solutions, further enriched by a focus on digital transformation, artificial intelligence, and the principles of sustainable development. More... List of Study Fields for Submissions according to ISCED-F 2013: 0311 Economics 0412 Finance, banking and insurance 0413 Management and administration 0414 Marketing and advertising 0416 Wholesale and retail sales 0612 Database and network design and administration 0613 Software and applications development and analysis 0712 Environmental protection technology 0713 Electricity and energy 0714 Electronics and automation 0715 Mechanics and metal trades 0716 Motor vehicles, ships and aircraft 0788 Inter-disciplinary programmes and qualifications involving engineering, manufacturing and construction By sections...
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Physics-Informed Neural Networks in Aerospace: A Structured Taxonomy with Literature Review
Section: Aerospace vehicles Categories: Artificial Intelligence, Aerospace Engineering Keywords (enter each keyword separately and confirm each by pressing Enter): Physics-Informed Neural Networks (PINNs), aerospace engineering, machine learning, mathematical simulation, flight vehicles, aerospace design Purpose. This study aims to develop a structured four-tier taxonomy that systematically organizes aerospace engineering tasks suitable for the application of Physics-Informed Neural Networks (PINNs), while validating this classification through a literature review and identifying opportunities for future research. Design / Method / Approach. The methodology involves grouping tasks into four distinct tiers—Physical Modeling, Dynamic Analysis, Functional Assessment, and System-Level Assessment—based on their physical, operational, and systemic characteristics. This framework is subsequently populated with real-world examples derived from the analysis of 145 peer-reviewed studies. Findings. The reviewed literature confirms a balanced distribution of PINNs applications across all tiers. Contrary to initial assumptions, studies were identified even in areas previously presumed underrepresented, such as acoustic modeling, optical simulations, and environmental impact assessment. This outcome reveals the broader applicability of PINNs and calls for a reassessment of current assumptions regarding underexplored domains. Theoretical Implications. The proposed taxonomy offers a coherent framework for structuring interdisciplinary PINNs applications by integrating physics-based modeling with machine learning across aerospace engineering contexts. Practical Implications. It provides engineers and researchers with a practical roadmap for selecting PINNs methods tailored to specific problem types, potentially improving computational efficiency and enhancing predictive accuracy in aerospace design and analysis. Originality / Value. The study’s originality lies in its empirically validated, four-tier taxonomy that synthesizes the fragmented body of literature on PINNs in aerospace, offering a unified perspective for researchers and practitioners. Research Limitations / Future Research. While the taxonomy covers a wide range of existing applications, future studies should consider extending it with new tiers—particularly related to manufacturing-aware modeling—and pursue methodological standardization to ensure reproducibility and scalability. Article Type. Review. PURL: https://purl.org/cims/4.313
Physics-Informed Neural Networks (PINNs)
Copyright (c) 2025 Yurii Tkachov, Oleh Murashko (Author) https://creativecommons.org/licenses/by/4.0
Evaluation of dynamic characteristics of a linear time-varying system
Section: Control Systems, Telecommunications and Navigation Categories: Computational Theory and Mathematics, Aerospace Engineering, Control and Systems Engineering Keywords (enter each keyword separately and confirm each by pressing Enter): time-varying control system, transfer function, equivalence criterion, Levenberg-Marquardt algorithm Purpose. The development of methodological support for the construction of an algorithm for calculating the coefficients of the transfer function of the second order link, which is equivalent to a time-varying system in the selected time interval from the point of view of the smallest average value of the modulus of the difference of dimensionless state vectors. Design / Method / Approach. Mathematical models of a time-varying system and a second-order link are used, along with a criterion that determines the transfer function coefficients. The Levenberg-Marquardt algorithm finds the minimum, and the Runge-Kutta algorithm solves differential equations. The output of the time-varying system is obtained numerically, while the second-order link’s output is an analytical solution. Findings. Based on the calculations carried out for the selected data example, the possibility of determining the transfer function coefficients of the second-order link is shown, which, from the point of view of the smallest average value of the modulus of the difference of dimensionless state vectors on the selected time interval, is equivalent to time-varying system. Theoretical Implications. It is possible to have an estimate of the margin of stability, type and duration of the transient process during the selected time interval of the system operation by using the mathematical apparatus of linear stationary systems. Practical Implications. It leads to the expansion of the methodological base of analysis and synthesis of linear time-varying systems. Originality / Value. It lies in the using the Levenberg-Marquardt method to determine the coefficients of the transfer function which is equivalent to the equations of a time-varying system at a certain time interval from the point of view of the selected criterion. Research Limitations / Future Research. The algorithm was developed for the rocket rotational control system in one plane. The transfer function coefficients depend on constraints and the test signal within 15%. Further research includes an equivalent stationary approximation considering actuator inertia and center of mass disturbances. Article Type. Conceptual. PURL: https://purl.org/cims/4.250
Control Systems, Telecommunications and Navigation
Copyright (c) 2025 Volt Avdieiev (Author) https://creativecommons.org/licenses/by/4.0
The Impact of Emotionally Driven Service on Customer Loyalty in the Beauty Services Sector
Section: Project Management and Leadership Categories: Marketing, Strategy and Management Keywords (enter each keyword separately and confirm each by pressing Enter): emotional service, customer loyalty, beauty industry, personalized service, non-verbal communication, client experience Purpose. This article aims to theoretically substantiate and empirically investigate the impact of emotional service on customer loyalty in the beauty industry. It identifies key emotional interaction factors that enhance customer satisfaction and the competitive advantage of beauty service providers. Design / Method / Approach. The study employs an empirical approach based on a survey conducted at the “Women Place” beauty salon in Odesa, Ukraine. Forty regular clients participated, evaluating the significance of emotional and personalized service components. Data was analyzed using descriptive statistics and visualized through percentage-based charts. Findings. The research reveals that personalized communication, staff politeness, cleanliness, interior design, music, and aromatherapy influence customer loyalty. Emotional service plays a critical role in shaping positive client experiences and strengthening brand affiliation. Clients value not only service quality but also the emotional atmosphere and individual approach. Theoretical Implications. This study contributes to understanding emotional service as a strategic tool for loyalty development in the Ukrainian beauty industry. It broadens the theoretical framework by integrating emotional labor, non-verbal communication, and personalization into customer behavior analysis. Practical Implications. The findings offer practical recommendations for beauty business managers to improve emotional interaction processes, implement CRM systems, and develop customer-oriented strategies to retain clientele and reduce churn. Originality / Value. This is one of the first comprehensive empirical studies in Ukraine examining emotional service in loyalty formation, considering sensory, behavioral, and personalized dimensions. Research Limitations / Future Research. The study is limited to one beauty salon. Future research may compare other market segments and explore demographic factors influencing emotional service perception. Article Type. Applied Research. PURL: https://purl.org/cims/4.274
Copyright (c) 2025 Yelyzaveta Kravchuk , Oleksandr Krupskyi (Author) https://creativecommons.org/licenses/by/4.0
An Empirical Analysis of Turkey’s Foreign Trade Trends: 2015 – 2024
Section: Market Synergy Categories: Economics and Econometrics, Finance Keywords (enter each keyword separately and confirm each by pressing Enter): Turkish economy, trade balance, export, import, foreign trade, trade deficit Purpose. This article analyzes the trade balance of the Republic of Türkiye for 2015–2024, examining import–export dynamics over a ten-year interval and identifying the main drivers of the persistent deficit. Design / Methodology / Approach. The study draws on data from Trade Map, international trade statistics for business development, TURKSTAT, and open-data releases from other organizations; annual trade values and year-over-year growth rates were compared using descriptive statistics and time-series comparisons to assess trends and bilateral flows. Findings. Throughout the period, import values consistently exceeded export values, generating a sustained trade deficit. Although exports grew steadily, the faster rate of import growth resulted in a widening gap, indicating that Türkiye purchased more goods and services abroad than it sold. Theoretical Implications. The results underscore the value of empirical statistical analysis for understanding structural trade imbalances and support refinement of theoretical models addressing trade deficits in emerging economies. Practical Implications. Strategic imports—particularly energy products and industrial raw materials—have driven the deficit, with substantial volumes sourced from Russia and China; these insights can inform targeted import-substitution policies and measures to strengthen domestic production. Originality / Value. The research synthesizes multiple data sources to present updated empirical insights into Türkiye’s principal export markets (Germany, the USA, the UK) and largest import partners (China, Russia), and highlights diversification toward Asian and Caucasus nations over the study period. Research Limitations / Future Research. Future research should employ mathematical modeling techniques to test causality and explore counterfactual policy scenarios. Paper Type. Applied, Empirical article. PURL: https://purl.org/cims/4.285
Copyright (c) 2025 Esmer Aliyeva (Author) https://creativecommons.org/licenses/by/4.0
Modeling fin efficiency considering transverse temperature gradients in rocket engine cooling channels
Section: Engines, Energy and Thermotechnics Categories: Aerospace Engineering, Computational Mechanics Keywords (enter each keyword separately and confirm each by pressing Enter): mathematical model of heat transfer, transverse temperature non-uniformity, liquid propellant rocket engine, cooling channels of the engine chamber Purpose. This study aims to improve the accuracy of methods for determining fin efficiency. Its goal is to derive calculation relationships for finning coefficients that account for transverse temperature non-uniformity within the fin cross-section. Design / Method / Approach. The article presents the reduction of the heat conduction equation for a fin to a dimensionless form, based on dimensional analysis of the variables involved. Further development relies on analyzing the results of numerical simulations and their subsequent generalization. To this end, the gradient descent method is applied, minimizing the quadratic error function. Findings. A criterial dependence has been formulated to complement the derived heat conduction equation. Test calculations and comparisons with numerical simulations in Ansys Fluent confirm an improvement in calculation accuracy when using the proposed equation. Theoretical Implications. This paper addresses factors previously neglected in the analysis of heat transfer in fins. The results of the study thus complement existing approaches to determining finning coefficients. Practical Implications. The derived criterial relationship will enhance the accuracy of heat transfer calculations in the chambers and gas generators of liquid rocket engines. Originality / Value. The paper introduces an original criterial relationship that accounts for temperature non-uniformity across the fin cross-section. Incorporating this factor improves calculation accuracy, highlighting the practical value of the developed equation. Research Limitations / Future Research. This study focuses on rectangular fins; therefore, the proposed model is not applicable to fins with variable thickness in the ducts of liquid propellant rocket engines (LPREs). Developing a fin model without these limitations will be the objective of future research on this topic. Article Type. Applied Research. PURL: https://purl.org/cims/4.299
Copyright (c) 2025 Volodymyr Sliusariev, Valerii Bucharskyi (Author) https://creativecommons.org/licenses/by/4.0
Austenite Stability and Wear Resistance of High-Manganese Steels
Section: Structural and Functional Materials Categories: Mechanics of Materials, Metals and Alloys Keywords (enter each keyword separately and confirm each by pressing Enter): high-manganese steel, austenite, martensitic transformation, wear resistance, plastic deformation Purpose. Classification of wear-resistant components used in metallurgical equipment by category and optimization of high-manganese steel selection. Design / Method / Approach. The study was conducted on steels produced in induction furnaces with water quenching at 1050 °C. Samples of 5 × 3 × 3 mm³ were subjected to slow plastic deformation by compression. The degree of deformation was determined by the ratio of the sample thickness before and after deformation. The magnetic state was evaluated by the magnetometric method using a Faraday balance. Findings. At 20–30% deformation, 110Mn8 formed 2.787 vol.% α′-martensite, 110Mn10 – 0.263 vol.%, 110Mn13 – 0.107 vol.%, and 110Mn18 – 0.006 vol.%. Steels 110Mn8 and 110Mn10 exhibit low austenite stability, while 110Mn13 and 110Mn18 are metastable. A classification of parts by operating conditions was proposed: I – especially critical purpose (110Mn13, 110Mn18), II – critical purpose (110Mn10), III – general purpose (110Mn8). Theoretical Implications. The study enhances understanding of the role of martensitic transformation in the wear resistance of high-manganese steels and clarifies the relationship between chemical composition and austenite stability. Practical Implications. The classification enables optimized steel selection for parts based on operating conditions, reducing material costs and improving equipment reliability. Originality / Value. This is the first study to propose a classification of metallurgical equipment parts by categories, considering austenite stability, facilitating rational material selection. Research Limitations / Future Research. Future research should explore the effects of additional alloying elements and compare them with other deformation types. Article Type. Empirical. PURL: https://purl.org/cims/4.286
Copyright (c) 2025 Hennadii Snizhnoi , Volodymyr Sazhnev, Serhii Sheyko, Olexandr Shapurov, Anastasiia Hrechana (Author) https://creativecommons.org/licenses/by/4.0
Wet wipes in green ecosystems of Chernihiv, Ukraine
Section: Ecology, industrial and environmental safety Categories: Environmental Engineering, Pollution Keywords (enter each keyword separately and confirm each by pressing Enter): wet wipes, sustainable materials, Sustainable Development Goals, environmental education Purpose. To assess the pollution of recreation areas in Chernihiv with wet wipes and raise schoolchildren’s awareness of the related environmental problems. Design / Method / Approach. Direct counting of wet wipes on 100 m² in summer and autumn 2024. A socio-pedagogical study of schoolchildren’s awareness was conducted through a lecture and an online questionnaire before and after the lecture. Findings. Wet wipes were found as litter in recreation areas, indicating a low level of public awareness of their environmental impact. The smallest number of wet wipes was recorded in well-maintained or rarely visited areas. The highest (7 wipes/100 m²) was found in frequently visited but uncleaned areas without trash bins. The lecture “EcoSecrets of Wet Wipes” resulted in a positive shift in students’ perceptions, making them more aware of wet wipes as environmental pollutants containing hazardous substances and microplastics. Theoretical Implications. The findings expand the understanding of the environmental hazard posed by wet wipes and emphasize the need to mitigate their negative impact, particularly by educating schoolchildren about wet wipe pollution. Practical Implications. Raising awareness among children about responsible wet wipe use and the need to enhance their biodegradability and environmental safety. This supports the achievement of Sustainable Development Goals by promoting more conscious consumption habits. Originality / Value. This study is the first ecological assessment of urban pollution caused by wet wipes in Ukraine and the first socio-pedagogical study on schoolchildren’s awareness of this issue. Research Limitations / Future Research. Further educational and awareness-raising activities among school and university students regarding the environmental hazards of wet wipes, aligned with Sustainable Development Goals. Article Type. Applied Research. PURL: https://purl.org/cims/4.268
Ecology, industrial and environmental safety
Copyright (c) 2025 Nataliia Tkachuk, Dariia Zahryva (Author) https://creativecommons.org/licenses/by/4.0
Structure and physical properties of the rapidly cooled amorphous alloy FeCo0,854Nb0,146NiB0,7Si0,3
Section: Structural and Functional Materials Categories: Electronic, Optical and Magnetic Materials, Surfaces, Coatings and Films Keywords (enter each keyword separately and confirm each by pressing Enter): multicomponent high-entropy alloy, metallic glass, amorphous film, relative electrical resistivity, soft magnetic properties, microhardness Purpose. The study aims to develop and characterize a new nanostructured FeCo0,854Nb0,146NiB0,7Si0,3 high-entropy metallic glass with enhanced soft magnetic and mechanical properties. The research seeks to explore the interplay between the alloy’s amorphous structure and its functional properties to advance the understanding of high-entropy metallic glasses. Design / Method / Approach. The amorphous films of the FeCo0,854Nb0,146NiB0,7Si0,3 alloy was synthesized using splat-quenching technique. The cooling rate, estimated based on the film thickness, was ~106 K/s. Structural properties were analyzed via X-ray diffraction (XRD), differential thermal analysis (DTA), and electrical resistivity measurements. Magnetic properties were assessed using a B–H curve tracer and vibrating sample magnetometer, while microhardness was measured with a PMT-3 tester. Findings. The alloy exhibits a fully glassy structure with a crystallite size of ~3 nm, low coercivity (40 A/m), high saturation magnetization (74 A·m2/kg), and microhardness ≥ 8000 MPa, indicating decent soft magnetic and mechanical properties. Theoretical Implications. The research provides significant insights into the role of atomic-size differences, configurational entropy, and thermodynamic parameters in stabilizing the glassy phase in high-entropy alloys. It advances the theoretical framework for designing high-entropy amorphous materials. Practical Implications. The characteristics of the material make it promising for use in electronic devices and mechanical engineering parts. Originality / Value. This study provides a comprehensive analysis of the high-entropy metallic glass FeCo0,854Nb0,146NiB0,7Si0,3, offering new insights of its magnetic and mechanical properties through advanced characterization techniques. Research Limitations / Future Research. Further studies are needed to investigate the long-term stability of the fabricated amorphous alloy. Article Type. Applied Research. PURL: https://purl.org/cims/4.284
Electronic, Optical and Magnetic Materials
Copyright (c) 2025 Oleksandr Kushnerov, Valerii Bashev, Serhii Ryabtsev (Author) https://creativecommons.org/licenses/by/4.0
Current State of Renewable Energy Development in Ukraine and Possible Solutions
Section: Ecology, industrial and environmental safety Categories: Energy Engineering and Power Technology, Renewable Energy, Sustainability and the Environment Keywords (enter each keyword separately and confirm each by pressing Enter): Renewable energy sources, wind power, wind energy potential, wind power plants in Ukraine, wind power plants, environmental factors Purpose. To examine the current state of development and implementation of renewable energy sources in Ukraine and to investigate the prospects for their utilization. Design / Method / Approach. The study analyzes the current state and prospects of renewable energy sources use worldwide and in Ukraine, presents the inventory and current status of wind power plants in Ukraine considering the impact of military actions. The most efficient wind energy installations for mining regions are identified, along with their advantages and disadvantages. Findings. The prospects for the use of wind energy installations to ensure the country’s energy security are established; it is emphasized that wind power plants (WPPs) represent one of the most competitive electricity generation technologies, with economic and ecological benefits. Theoretical Implications. The advantages of WPPs, conditions for their application, and promising directions for their use, including the possibility of placement on technogenically disturbed lands, are defined. Practical Implications. The existing WPPs in Ukraine, their current status, and the prospects for renewable energy development globally and nationally to ensure energy independence and security are analyzed. Originality / Value. The article provides original data on the current global status of renewable energy; it analyzes the relevance of renewable energy use during wartime and post-war periods for achieving energy independence through the deployment of WPPs on technogenically disturbed lands in mining regions. Research Limitations / Future Research. Further studies will focus on the potential use of wind energy installations with vertical axis rotation in mining regions on technogenically disturbed lands. Article Type. Empirical. PURL: https://purl.org/cims/4.298
Renewable Energy, Sustainability and the Environment
Copyright (c) 2025 Ольга Медведєва, Заряна Гальченко, Олексій Демченко (Автор) https://creativecommons.org/licenses/by/4.0
Economic growth of countries in the context of military operations
Section: Market Synergy Categories: Strategy and Management, Economics and Econometrics Keywords (enter each keyword separately and confirm each by pressing Enter): growth, military conflicts, growth models, machine learning, international aid Purpose. The purpose of the study is to assess the economic growth of Ukraine, Syria, and Palestine under wartime conditions, compare growth models (Solow, MRW, Romer, and a machine learning model), identify recovery factors, and develop recommendations for 2030. Design / Method / Approach. The study employs a comparative analysis of growth models, modified by a conflict intensity indicator, based on panel data from 1990–2023 (World Bank, UNESCO, IndexMundi). Random Forest, accounting for nonlinear relationships among variables (investments, education, R&D, international aid), was used for forecasting. Forecasts cover three scenarios for 2025–2030. Findings. The Romer model is the most accurate for Ukraine, projecting a GDP per capita of $13,456 (optimistic scenario, 2030). For Syria and Palestine, projections are $1,183 and $3,012, respectively. Random Forest predicts $23,792 for Ukraine, $6,819 for Syria, and $5,764 for Palestine. Key factors include international aid (29.8%), investments (24.6%), and conflict reduction (19.7%). Theoretical Implications. The study adapts growth models to wartime conditions, highlighting the advantages of endogenous models and machine learning for analyzing complex economies. Practical Implications. The findings contribute to developing recovery strategies, allocating international aid, and planning sustainable development in conflict-affected countries. Originality / Value. The originality lies in adapting models to wartime conditions, comparing their effectiveness, and applying Random Forest for forecasting. Research Limitations / Future Research. Limitations include a small sample size (72 observations), missing data, subjective assumptions, and omission of external shocks. Future research should incorporate broader data, climate, and geopolitical factors. Type of Article. Empirical. PURL: https://purl.org/cims/4.288
Copyright (c) 2025 Olexandr Shapurov, Oleksii Hrechanyi, Volodymyr Stoiev, Anatolii Karpelianskyi, Alina Sosnovska (Author) https://creativecommons.org/licenses/by/4.0
Flexible Leadership as the Key to Effective Project Team Management
Section: Project Management and Leadership Categories: Organizational Behavior and Human Resource Management, Strategy and Management Keywords (enter each keyword separately and confirm each by pressing Enter): flexible leadership, project management, team collaboration, emotional intelligence, transformational leadership, servant leadership Purpose. This article aims to provide an in-depth analysis of modern leadership models in project management, with a particular focus on flexibility, emotional intelligence, service orientation, and adaptability to dynamic environments. It explores the leader's role as a central factor in building cohesive, high-performing, and resilient project teams. Design / Method / Approach. The study employs comparative analysis, typology of leadership styles, interdisciplinary literature review, and logical-analytical synthesis. It draws on concepts from contemporary management, organizational behavior, and human resource leadership. Findings. The research identifies transformational, coaching, servant, and distributed leadership as the most effective approaches for fostering employee engagement, creativity, responsibility, and responsiveness. It outlines key factors influencing leadership model selection, including project type, team structure, and implementation phase. Theoretical Implications. The article expands the conceptual understanding of modern leadership in project management, emphasizing the shift in leadership paradigms and the importance of emotional intelligence. Practical Implications. The research offers practical recommendations for selecting leadership styles according to project-specific contexts, which may benefit project managers, consultants, and educators. Originality / Value. The article integrates multiple leadership models into the project management framework, allowing for a strategically flexible approach to team leadership. Research Limitations / Future Research. The study focuses on transformational, servant, and adaptive leadership in project management. Its scope is limited due to the complexity and diversity of leadership theories and the inability to examine all existing styles. To gain a deeper understanding of the effectiveness of various leadership models, it is necessary to conduct empirical validation of the findings across different industries and teams with diverse structures. Additionally, further research should explore the influence of organizational culture, industry specifics, and innovation levels on leadership model selection, particularly in the context of virtual teams and remote leadership. Article Type. Conceptual Paper. PURL: https://purl.org/cims/4.310
Organizational Behavior and Human Resource Management
Copyright (c) 2025 Sofia Savelieva, Yuliia Stasiuk (Author) https://creativecommons.org/licenses/by/4.0
Improvement of data flow management in the air traffic control automation system
Section: Control Systems, Telecommunications and Navigation Categories: Management Information Systems, Control and Systems Engineering Keywords (enter each keyword separately and confirm each by pressing Enter): data flow management, air traffic control system, information load Purpose. The research purpose is to improve the data flow management of the air traffic control system of the Danylo Halytskyi International Airport “Lviv”. Design / Method / Approach. The following methods and approaches were consistently used in the research: system approach; modeling; content analysis; statistical analysis; project approach; economic analysis. Findings. Recommendations have been developed for optimizing data flow processing, including improving technological solutions, increasing the level of automation, and implementing strategies to reduce stress on controllers. The features and effectiveness of air traffic management and the data flow network of the automated control system of the Danylo Halytskyi International Airport “Lviv” have been studied. The program has been developed to improve the effectiveness of air traffic management and the data flow network of the automated control system of the Danylo Halytskyi International Airport “Lviv”. The effectiveness of the implementation of the program to improve air traffic management and the data flow network of the automated control system of the Danylo Halytskyi International Airport “Lviv” has been substantiated. Theoretical Implications. Methodological aspects of data flow management of the automated air traffic control system network have been investigated. Practical Implications. Directions for increasing the efficiency of air traffic control and data flow management of the automated control system network of the Danylo Halytskyi International Airport “Lviv” have been developed and substantiated. Originality / Value. The implementation of the modern technical and methodological solutions proposed in the article for the automation of air traffic control and data processing will contribute to reducing risks, increasing the speed of decision-making and ensuring the stable operation of all aviation processes. Research Limitations / Future Research. Future research into mechanisms for improving air traffic management and data flows at airports is an important task from both a scientific and a practical point of view. Article Type. Applied Research. PURL: https://purl.org/cims/4.281
Copyright (c) 2025 Ганна Калашник, Мирослава Калашник-Рибалко, Артем Михайлецький (Автор) https://creativecommons.org/licenses/by/4.0
Multi-criteria optimization of composite panels with rib reinforcement under combined loading
Section: Aerospace vehicles Categories: Aerospace Engineering, Computational Mechanics Keywords (enter each keyword separately and confirm each by pressing Enter): composite panels, stiffeners, vector optimization, integral quality criterion, human-machine procedure Purpose. The study is aimed at finding a constructive balance between the mass and cost of composite panels with stiffeners that are subjected to combined loading. The optimization was carried out taking into account real operation conditions, when a slight improvement in one of the parameters can significantly affect the efficiency of the structure. Design / Method / Approach. The work integrates engineering mechanics and mathematical modeling with the construction of a vector optimization model, for the solution of which the procedure of forming an integral quality criterion was applied, which considers expert assessment and the principle of guaranteed results. Conclusions. The proposed methodology allows not only to determine the optimal structural parameters for panels with different reinforcement options but also provides flexibility for adaptation to variable loads and constraints. The model was successfully tested on the example of six load scenarios for panels with rectangular and angular ribs. Theoretical implications. The development contributes to the development of multi-criteria optimization of composite structures, in particular by refining models and expanding the principles of evaluating the trade-off between criteria. This lays the foundation for further research in the field of aircraft design, where criteria may contradict each other. Practical implications. The results formed the basis for the creation of a software package that allows for the determination of the most appropriate options for structural reinforcement depending on the constraints and requirements. Originality / Value. The human-machine decision-making system underlying the approach allows for expert intuition to be considered without losing the accuracy of mathematical modeling. This is extremely valuable for industries where every gram of weight and every hryvnia of costs are critical. Research limitations / Further research. The main limitation is the focus on only two criteria – mass and cost. Further exploration should be directed towards expanding the number of indicators. Article Type. Applied Research. PURL: https://purl.org/cims/4.278
Copyright (c) 2025 Mykola Mormul, Oleksandr Shchytov, Dmytro Shchytov (Author) https://creativecommons.org/licenses/by/4.0
Optimizing Material and Technology Selection for Cost-Effective Equipment Performance
Section: Structural and Functional Materials Categories: Industrial and Manufacturing Engineering, Metals and Alloys Keywords (enter each keyword separately and confirm each by pressing Enter): high-manganese steel, austenite, martensitic transformation, wear resistance, plastic deformation Purpose. To optimize criteria for evaluating the implementation of wear-resistant materials to reduce production costs and equipment downtime. Design / Method / Approach. The study employed an analytical review of publications, spectral and metallographic analysis of alloys, a gravimetric method for assessing wear resistance, and heat treatment to enhance it. Findings. An analysis of challenges in developing materials for mining, metallurgical, and construction equipment was conducted. It was established that component service life must align with equipment maintenance schedules. New materials with enhanced wear resistance may be economically unviable due to high costs or inability to realize durability benefits. A balance between cost and service life is achieved by analyzing operating conditions and defining material and technology requirements. Theoretical Implications. The study expands knowledge on reducing production costs by identifying criteria for the effective implementation of materials and technologies. Practical Implications. A multi-criteria analysis is proposed for adopting new materials and technologies in the production of components for mining, metallurgical, and construction equipment, reducing costs and downtime. Originality / Value. The methodology uniquely optimizes material selection by aligning component durability with maintenance schedules, minimizing downtime. Its innovative alloy development resolves conflicting material requirements, enhancing production efficiency. Research Limitations / Future Research. Limitations include a focus on specific materials; future research should explore a broader range of materials and conditions. Article Type. Empirical. PURL: https://purl.org/cims/4.287
Industrial and Manufacturing Engineering
Copyright (c) 2025 Valerii Netrebko, Vadym Shalomieiev, Serhii Sheiko, Olexandr Shapurov, Oleksii Hrechanyi, Valentyna Tretiak (Author) https://creativecommons.org/licenses/by/4.0
Transfer Function of a Time-Varying Control System Considering Actuator Inertia
Section: Control Systems, Telecommunications and Navigation Categories: Aerospace Engineering, Control and Systems Engineering Keywords (enter each keyword separately and confirm each by pressing Enter): time-varying control system, transfer function, equivalence criterion Purpose. Methodological support for building an algorithm for determining the transfer function (TF) of a link, which, considering the actuator dynamics and the disturbed motion of the mass center, is equivalent on a selected trajectory section to a time-varying control system (TCS) for the rocket movement in one plane. Design / Method / Approach. TCS is modeled using differential equations with changing coefficients. To define the type of TF, the Laplace transformation of the equations is performed, while its coefficients are determined by finding the equivalence criterion extreme of the output signals of the TCS and the link under the action of the test signal. Findings. The example of the TCS for the rocket movement in the yaw plane shows the possibility of an algorithm constructing for studying its dynamic characteristics by using the mathematical apparatus of linear stationary systems. Theoretical Implications. Finding the extreme of the equivalence criterion of the TCS and the link using the Levenberg-Marquardt method, with the coordinates of the extreme point being the arguments of the TF coefficients. Practical Implications. Using the TF of equivalent link, it is possible to obtain for the selected trajectory section a quantitative estimate of the stability margin, the duration of the transient process, the accuracy of disturbance compensation, and the transmission coefficient depending on the signal frequency input. The obtained results contribute to the methodological base expansion for linear time-varying systems research. Originality / Value. Analytical solution of the link differential equation for a test signal in the form of a sequence of rectangular and parabolic pulses using the Laplace transform. This will make it possible to obtain estimates of individual indicators of systems with time-varying parameters by using the mathematical apparatus of stationary systems. Research Limitations / Future Research. The algorithm is for the case of TCS of a rocket motion in one plane developed. The next stage of the study is to assess the algorithm complexity level as the order of the TCS mathematical model increases. Article Type. Methodological. PURL: https://purl.org/cims/4.280
Open-source analysis of the potential configuration and kinetic performance of the Oreshnik ballistic missile
Section: Aerospace vehicles Categories: Aerospace Engineering, Mechanical Engineering Keywords (enter each keyword separately and confirm each by pressing Enter): Oreshnik system, kinetic warhead, suborbital trajectory, aerodynamic heating, propulsion configuration, ballistic missile Purpose. This article presents an analysis of the tactical and technical characteristics of the Oreshnik medium-range ballistic missile, which, according to open-source data, was employed in a precision strike against an infrastructure facility in Dnipro in November 2024. The study focuses on the missile’s configuration, warhead type, and aerodynamic behavior using open-source information. Design / Method / Approach. An interdisciplinary methodology was applied, comprising Sentinel-2 satellite imagery analysis, kinetic-energy and aerodynamic-heating modeling, and comparative assessment against the Russian Avangard, Rubezh, and UR-100N UTTKh platforms. Missile debris and factory markings were used to reconstruct manufacturing chronology and identify design features. Findings. It was determined that Oreshnik is equipped with a hypersonic non-explosive kinetic warhead capable of destructive impact via high-velocity collision. The missile likely follows a suborbital trajectory, achieving speeds of 11–12 km/s and surface temperatures in excess of 4300 K. Markings indicate key components were manufactured in 2017, suggesting reuse of legacy platforms. Theoretical Implications. This work advances the theory of kinetic-impact systems by elucidating thermal-loading mechanisms and energy-transfer processes in hypersonic vehicles, thereby bridging contemporary implementations with the historical “Rods from God” concept. Practical Implications. The findings reveal limited strike effectiveness owing to high costs and moderate destructive yield, yet underscore the system’s value as a demonstrator technology and its utility for hypersonic-system testing. Originality / Value. This study constitutes the first technical analysis of an Oreshnik missile strike based exclusively on open-source data, illustrating the growing role of civilian satellite imagery and interdisciplinary modeling in arms-monitoring. Research Limitations / Future Research. The analysis relies solely on open-source information. Future work should include detailed damage assessment, thermal-protection analysis, and expanded trajectory modeling with advanced software tools. Enhanced monitoring of high-velocity conventional weapons is recommended to support arms-control and humanitarian-law frameworks. Article Type. Applied research. PURL: https://purl.org/cims/4.306
Copyright (c) 2025 Mykola Bondarenko, Volodymyr Habrinets, Mykhailo Vorobei (Author) https://creativecommons.org/licenses/by/4.0
Integration of Emotional Intelligence and Neuropsychological Approaches into Educational Crisis Management
Section: Project Management and Leadership Categories: Organizational Behavior and Human Resource Management, Strategy and Management Keywords (enter each keyword separately and confirm each by pressing Enter): emotional intelligence, crisis management, education, neuropractices, psychological support, emotional self-regulation Purpose. Theoretical substantiation and practical modeling of the integration of psychological resources of emotional intelligence and neuro-approaches into the crisis management system in education. The focus is on identifying effective tools to support participants in the educational process under conditions of social instability, war, emotional exhaustion, and professional burnout. Design / Method / Approach. Interdisciplinary study combining psychological analysis, conceptual modeling, systemic educational management, teacher surveys, and systemic intervention modeling. Findings. The research substantiates integrating emotional intelligence (for psycho-emotional stability) and neuropractices (for internal resource activation) into educational crisis management. A proposed model integrates cognitive-emotional regulation, body-oriented techniques, and reflective practice for a safe educational environment. Theoretical contribution. Clarifies educational crisis management framework, expands emotional intelligence use as systemic psycho-pedagogical support, and reveals neuropsychological practices' potential in regulating educator stress responses. Practical implications. Results applicable for educational managers, tutors, and teacher professional development. Tools help reduce emotional burnout, increase stress resilience, and enhance crisis decision-making. Originality / Value. Innovative integration of psychological and neuropsychological tools into educational management. Uniquely presents emotional intelligence as a strategic resource for educational management under crisis. Research limitations / Future research. Applied study, limited by small pilot sample and short observation period. Future research: long-term assessment, model scaling, adaptation across diverse educational institutions. Type of article. Applied Research. PURL: https://purl.org/cims/4.302
Copyright (c) 2025 Yuliia Starova (Author) https://creativecommons.org/licenses/by/4.0
Elasticity-Driven Fare Optimization in U.S. Air Travel Segments
Section: Market Synergy Categories: Management Science and Operations Research, Economics and Econometrics Keywords (enter each keyword separately and confirm each by pressing Enter): demand elasticity, market segmentation, distance-based pricing, revenue management, dynamic pricing, U.S. air travel market Purpose. This study investigates the variation in price elasticity of demand across U.S. domestic air travel markets, with a particular focus on how different distance-based market segments respond to airfare changes. Design / Method / Approach. The analysis presents air travel markets in the distance categories of very short, short-haul, medium-haul, and long-haul to analyze the heterogeneous nature of price responses. Findings. The results indicate substantial differences in elasticity across directions. In the short-haul markets, the negative price elasticity demonstrates strong awareness of fare increases (ε=-0.344). Conversely, long-haul markets demonstrate price elasticity in a positive direction (ε = +1.840), indicating perceptions of value-added (i.e., direct services quality or even network effects). Medium-haul distances suggest nearly neutral responses, and the very short routes produce statistically insignificant elasticity coefficients. Theoretical Implications. The research expands transportation economics and marketing analytics literature through the analytic demonstration that distance travelled does impact demand elasticity in the case of airline routes. The study provides additional evidence for segmentation theories and distance-based price models. Practical Implications. The results provide airline revenue managers with data-based evidence that depicts the opportunity to develop fare structures that align closer to consumer behaviors and may provide opportunities for enhanced profits by utilizing distance and type of flight configurations. Originality / Value. This study employs an entirely unique segmentation-based approach to enable an elasticity analysis of city-pair air travel market distances by utilizing a wealth of longitudinal data to provide evidence-based recommendations for both academics as well as practitioners. Research Limitations / Future Research. Limitations include the exclusion of international routes and ancillary pricing factors. Future research may explore dynamic pricing strategies in real-time or investigate elasticity in the context of loyalty programs and airline alliances. Article Type. Research article. PURL: https://purl.org/cims/4.316
Management Science and Operations Research
Copyright (c) 2025 Annur Islam Sifat, Md Adnan Elahi (Author) https://creativecommons.org/licenses/by/4.0
Statistical Analysis and Forecasting of Injury-Related Road Accidents in Dnipropetrovsk Region
Section: Ecology, industrial and environmental safety Categories: Statistics, Probability and Uncertainty, Safety, Risk, Reliability and Quality Keywords (enter each keyword separately and confirm each by pressing Enter): road traffic accidents, road safety, analysis of variance, forecasting, , temporal factors, seasonality , correlation and regression analysis Purpose. The study aims to identify seasonal and weather-related factors influencing the number of road traffic accidents (RTAs) with casualties in Dnipropetrovsk Oblast, in order to provide a basis for short-term accident forecasting and improve the effectiveness of traffic safety prevention measures. Design / Method / Approach. The study is based on monthly statistical data from 2020 to 2025, sourced from the Patrol Police of Ukraine and the Main Department of Statistics in Dnipropetrovsk Oblast. The analysis integrates boxplot visualization, one- and two-way ANOVA, correlation analysis, and multiple regression analysis, accounting for temperature, precipitation, humidity, wind speed, and calendar month. Findings. A statistically significant impact of the calendar month was confirmed as the main seasonal factor. The regression model showed a clear link between RTAs and combined weather and calendar variables. Accident rates peaked in summer–autumn and dropped in winter–spring, with February showing the least variation. Monthly factors proved useful for short-term forecasting. Time series analysis enabled tracking trends (2020–2024) and projecting them through 2026. Theoretical Implications. The results enhance the understanding of the interplay between seasonal, calendar, and weather-related factors and accident rates within a regional context. Practical Implications. The findings can be used by local authorities, police, and road safety services to plan preventive measures during periods of increased accident risk. Originality / Value. A comprehensive approach is proposed for analyzing RTAs at the regional level, involving various types of statistical analysis and seasonal forecasting. The methodology can be adapted for other regions of Ukraine. Research Limitations / Future Research. The study is limited to the 2020–2025 period and does not account for social, behavioral, or infrastructure-related factors. Future research should incorporate additional explanatory variables and apply multifactor forecasting methods. Article Type. Applied Research. PURL: https://purl.org/cims/4.311
Copyright (c) 2025 Tetiana Rusakova (Author) https://creativecommons.org/licenses/by/4.0
Optimization Problem of the Launch Vehicle Pitch Angle during Spacecraft Insertion into Circular Orbits
Section: Control Systems, Telecommunications and Navigation Categories: Aerospace Engineering, Control and Systems Engineering Keywords (enter each keyword separately and confirm each by pressing Enter): launch vehicle dynamics, spacecraft circular orbit insertion, mathematical model, pitch angle program, orbital trajectory optimization Purpose. The aim of the study is to formulate and analytically pose the task of constructing the pitch program of a launch vehicle, ensuring the insertion of a spacecraft into a circular orbit, considering constraints on the motion parameters and requirements for the final state. Design / Method / Approach. An analytical model for the pitch program is proposed, consisting of five phases: vertical ascent, angular acceleration, constant angular velocity motion, deceleration, and a final fixed-angle phase. Dimensionless coefficients are introduced to characterize the relative durations of active angular maneuver phases. Findings. Analytical expressions were derived for the pitch angle, angular velocity, and acceleration for each control phase, ensuring continuity and physical realizability. Expressions for the resulting orbital altitude and control effort provide a basis for multi-criteria optimization. Theoretical Implications. The developed formalization enables analytical optimization of the pitch program without a full vehicle motion model, aiding understanding of the link between control structure and orbital injection conditions. Practical Implications. The proposed model can be used in preliminary design stages for initial synthesis of the launch vehicle pitch program, enabling rapid assessment of trajectory controllability and compliance with specified orbital parameters, avoiding full-scale simulation. Originality / Value. Unlike approaches based on full numerical integration, this study presents a simplified, analytically manageable pitch program model, allowing efficient optimization considering physical constraints and final conditions. Research Limitations / Future Research. Limitations involve the simplified analytical model with fixed control phases. Future work involves numerical optimization (using gradient-based, heuristic, or global methods) to precisely determine optimal pitch program parameters. Article Type. Methodological paper. PURL: https://purl.org/cims/4.289
Copyright (c) 2025 Руслан Кеба, Анатолій Кулабухов (Автор) https://creativecommons.org/licenses/by/4.0
On the modification of direct methods for solving optimal control problems of stationary thermal processes
Section: Control Systems, Telecommunications and Navigation Categories: Computer Science Applications, Control and Systems Engineering Keywords (enter each keyword separately and confirm each by pressing Enter): stationary thermal process, control, system state, objective functional, gradient method, modified algorithm, efficiency Purpose. The aim of the study is to apply modified gradient-type methods to problems of optimal control of one-dimensional stationary thermal processes and to conduct a comparative analysis of the effectiveness of the classical and modified approaches using the example of solving specific problems. Design / Method / Approach. The research is focused on the development and numerical implementation of approximation-iteration algorithms based on the grid method for the analysis of controlled thermostatic systems modeled by differential equations with variable coefficients. For the numerical solution of the primary and adjoint boundary value problems, second-order accuracy difference schemes are used. To find the lower boundary of the objective functional, gradient-type minimization methods are used, both with and without control constraints. Findings. The proposed modified computational schemes demonstrate an increase in the efficiency of the classical grid method in terms of the amount of required computational costs and the accuracy of the obtained approximate solutions. Theoretical Implications. Expanding the possibilities of applying theoretically substantiated direct methods of accelerated convergence to solving optimal control problems of stationary thermal processes. Practical Implications. Creating an effective computational tool for solving optimal control problems of stationary thermal processes, which can be applied in practice. Originality / Value. Implementation of new computational schemes of accelerated convergence of modified gradient-type methods for the specified class of optimal control problems. Research Limitations / Future Research. The research limitations are due only to the properties of the programming language and software used. Further research involves applying the proposed modified approach to solving more complex optimal control problems, including multidimensional and phase-constrained ones. Article Type. Applied Research. PURL: https://purl.org/cims/4.314
Copyright (c) 2025 Liudmyla Hart, Anna Buhaienko (Author) https://creativecommons.org/licenses/by/4.0