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Numerical and Experimental Analysis of Free Vibrations of Thick-Walled Cylindrical Shell

2026-01-01T00:00:00Z

Назва: Numerical and Experimental Analysis of Free Vibrations of Thick-Walled Cylindrical Shell Автори: Grigorenko, Alexander; Müller, Wolfgang; Borysenko, Maksym; Бойчук, Олена Володимирівна; Boychuk, Olena Короткий огляд (реферат): Free vibrations of an isotropic thick-walled circular cylindrical shell with one end rigidly clamped, and the other free, are investigated numerically and experimentally. The natural frequencies and corresponding mode shapes are determined using the finite element method within a three-dimensional elasticity formulation, employing solid finite elements. The article focuses on constructing a reliable finite element model, including selecting element types and mesh density based on accuracy, convergence, and computational efficiency. In the article, solve a test problem to verify the numerical model and present a detailed convergence analysis. An experimental study of free vibrations based on stroboscopic interferometry, which allows full-field visualization of vibration mode shapes and determination of natural frequencies with sufficient accuracy. A comparison between numerical and experimental results demonstrates good agreement, confirming the reliability of the proposed modeling approach. The research study has been used in the design and analysis of thick-walled cylindrical shell structures in engineering applications, as well as for validating numerical and analytical methods for the vibration analysis of shell systems.

Methodology for investigating the interference immunity of satellite navigation antenna arrays using ansys hfss

2026-01-01T00:00:00Z

Назва: Methodology for investigating the interference immunity of satellite navigation antenna arrays using ansys hfss Автори: Slyusar, Vadym; Атаманюк, Ігор Петрович; Atamanyuk, Igor; Sliusar, Ihor; Shelemin, Zakhar; Sidenko, Ievgen; Kondratenko, Yuriy Короткий огляд (реферат): This paper presents an HFSS-based procedure for quantifying the interference resilience of satellite-navigation antennas on autonomous platforms that employ digital antenna arrays and controlled reception pattern antennas (CRPAs). An individual element is first simulated to determine the operating band under the VSWR<2 criterion and to select the analysis frequency. The complete array is then solved with in-phase excitation to obtain the zenith peak gain P. Next, a phase distribution that enforces a zenith null is identified, the associated gain depression D is measured, and interference suppression is expressed as P−D. The workflow is demonstrated on navigation CRPAs of several topologies. A six-element ring yields a relative null depth of about 36.5 dB, whereas a seven-element ring provides up to 45 dB of suppression. The strongest performance is achieved by a dual-ring 16-element array, reaching a 53 dB null depth. A square 4×4 array is lower by 8.5 dB. In further research, it would be advisable to experimentally test the influence of phase errors and also to extend this approach to other electromagnetic simulators.

Business Models of Hospitality Industry Enterprises: Economic and Managerial Aspect

2026-01-01T00:00:00Z

Назва: Business Models of Hospitality Industry Enterprises: Economic and Managerial Aspect Автори: Банєва, Ірина Олексіївна; Baneva, Irina; Іваненко, Тетяна Яківна; Ivanenko, Tetyana; Павлюк, Світлана Іванівна; Pavliuk, Svitlana; Кушнірук, Віктор Степанович; Kushniruk, Viktor; Гарбар, Галина Анатоліївна; Harbar, Halina Короткий огляд (реферат): The study examines the transformation of business models in the hospitality industry in response to digital technologies, platform integration, and changes in consumer behaviour. To identify patterns in business model development and to develop a methodological approach for assessing their effectiveness based on digital maturity and managerial factors. Design/Methodology/Approach: The article combined elements of a systematic review with empirical research, thereby developing a comprehensive analytical framework for evaluating the effectiveness of business models in the hospitality industry, incorporating digital, financial, and behavioural metrics. The research is based on a combination of statistical analysis and economic-mathematical modelling. The empirical dataset includes 42 hospitality enterprises over the period 2021–2025. Indicators were normalised using min-max transformation, and integral indices of digital maturity and business model effectiveness were constructed through weighted aggregation. The relationships between variables were estimated using multiple regression analysis with control variables (enterprise size, occupancy rate, cost structure, and OTA share). Model validity was tested using R², F-statistics, Durbin–Watson test, and multicollinearity diagnostics. Research Limitation: The study is limited by the sample size and the focus on retrospective data from 2021–2025, which may restrict generalisation to other regions or future market conditions. Findings: The results reveal a strong and statistically significant positive relationship between digital maturity and business model effectiveness. The regression model explains 73% of the variance in performance, confirming the dominant role of digital factors compared to traditional operational parameters. A 0.1-point increase in digital maturity leads to measurable improvements in performance indicators. Businesses with higher digital integration demonstrate increased profitability, higher conversion rates, and improved customer lifetime value. At the same time, growing dependence on platform channels affects revenue structure and margins. Practical Implication: The proposed integrated evaluation model can be used by hospitality enterprises to optimise business models, improve management decisions, and enhance digital transformation strategies. It provides a tool for balancing platform dependence, operational efficiency, and customer-oriented innovation. Social Implication: The development of digitally integrated and adaptive business models enhances service quality, accessibility, and sustainability in the hospitality sector, thereby supporting broader economic development and consumer welfare. Originality/Value: The study introduces a comprehensive analytical framework that integrates digital, financial, and behavioural indicators into a unified model to assess business model effectiveness in the hospitality industry, offering both theoretical advancement and practical applicability.

How sustainability narratives shape consumer perception: a semantic study of chicken meat marketing

2026-01-01T00:00:00Z

Назва: How sustainability narratives shape consumer perception: a semantic study of chicken meat marketing Автори: Бурковська, Анна Іванівна; Burkovskaia, Anna Короткий огляд (реферат): Purpose. This study examines how semantic cues in food marketing, particularly sustainability-oriented narratives, influence consumer perceptions of chicken meat. Methodology. The study was based on a survey of 128 consumers conducted in the retail chains Silpo, ATB, and MIDA in Mykolaiv, Ukraine. Respondents assessed various semantic configurations of chicken meat labelling, which differed by script (Latin versus Cyrillic), language (Ukrainian versus English), and the inclusion or omission of the “ECO” prefix. Evaluations were provided using a five-point scale. The analysis examined the extent to which these semantic variations shape consumer perceptions across six key dimensions: perceived product quality, taste expectations, purchase appeal, social prestige, environmental friendliness, and perceived support for local communities. Results. The findings indicate that consumer perceptions of chicken meat in Ukraine are strongly influenced by visual and semantic elements embedded in product naming, particularly language choice, script type, and the inclusion of sustainability-related markers. The study highlights the significant role of sustainable development narratives in shaping product image. Empirical evidence confirms that the “ECO” prefix serves as a powerful signal, reinforcing associations with environmental responsibility and social value, while at the same time potentially prompting more critical consumer judgment. Furthermore, product names that reflect national linguistic identity generate greater trust and a stronger sense of authenticity compared to foreign-language or transliterated alternatives. In general, the findings suggest that the incorporation of sustainability-oriented semantic cues into food marketing strategies can strengthen consumer trust and contribute to building a positive brand image within the Ukrainian chicken meat market. Originality. This study provides empirical evidence of how semantic patterns, specifically language choice, script, and the “ECO” prefix, shape consumer perceptions of chicken meat in Ukraine. The study identifies the role of eco-labelling in influencing expectations of quality, taste, and social responsibility, highlighting both positive and critical consumer responses. It also demonstrates that semantic cues not only affect purchasing behaviour, but also contribute to the formation of sustainability-related narratives and consumer trust in local food production. Practical implications. The results are useful for food producers, marketers, and policymakers in developing labelling and branding strategies that integrate sustainability-oriented narratives. The findings show how language choice, script, and eco-labelling influence consumer perception, providing guidance for building trust, emphasising product authenticity, and communicating environmental and social values more effectively.