Communications - Scientific Letters of the University of Zilina - Online first

Modelling and Optimization of Hydrogen Fuel Systems in Railway Vehicles Using Data Analysis and Machine Learning

Oleksandra Shepel, Ján Dižo, Miroslav Blatnický, Martin Bučko

Communications - Scientific letters of the University of Zilina X:X | DOI: 10.26552/com.C.2026.045  

Hydrogen fuel cell systems offer a zero-emission alternative to diesel-powered trains, combining high energy density with the potential for renewable energy integration. A hybrid data-driven modelling and optimization approach of improving the efficiency, reliability, and cost-effectiveness of hydrogen fuel systems for rail applications is developed in this research. Using operational and thermodynamic data from simulated and experimental sources, a predictive model of fuel cell performance based on non-linear regression and machine learning methods was developed. Results indicate that the data-driven model predicts system efficiency with a mean absolute...

Adapting D-Fmea to Increasing Product Complexity: A Study of Conventional and Mechatronic Shock Absorbers

Łukasz Rudolf, Marek Roszak, Lenka Kuchariková

Communications - Scientific letters of the University of Zilina X:X | DOI: 10.26552/com.C.2026.046  

The risk analysis is essential in product development, particularly as technical complexity increases. In this article the focus was on Design Failure Mode and Effects Analysis (D-FMEA) in the automotive industry. The conventional and electronically controlled shock absorbers as examples of a transition from a mechanical-hydraulic product to a more complex mechatronic system, are compared. In the study was considered how increasing complexity affects analysis boundaries, decomposition level, function description, interactions between components and subsystems, and the link between risk analysis and product validation. Based on industrial practice,...

Towards the Digital Twin-Enabled v2i Monitoring of Ship Power Plants under Real Operating Conditions

Andrii Holovan, Igor Gritsuk, Iryna Honcharuk, Olena Volska, Andrii L. Simanenkov, Artem A. Ivanov

Communications - Scientific letters of the University of Zilina X:X | DOI: 10.26552/com.C.2026.047  

In this paper is presented an ITS-oriented framework for monitoring and predictive assessment of ship power plants based on V2I communication and digital twin principles. The framework integrates onboard sensor data with environmental and operational information in a unified cyber-physical environment. A mathematical model and structured algorithm support state estimation, prediction, diagnostics, and decision-making under non-stationary conditions. The distributed architecture combines onboard systems, communication networks, and infrastructure-level processing. Validation using real operational data demonstrates that the framework captures variations...

Optimising Urban Traffic Flow through Green-Wave Signal Coordination: Effects on Delays, Fuel Consumption and Emissions in Baku

Mirhamid Baghirov, Heybatulla Ahmedov

Communications - Scientific letters of the University of Zilina X:X | DOI: 10.26552/com.C.2026.048  

In this study it was investigated how the traffic optimisation can reduce the environmental impact of urban transport. Traffic flows were modelled on a key urban road section, and traffic-light phases were optimised and synchronised to create smoother movement and reduce intersection delays. Data on traffic volume, delay time, fuel consumption and pollutant emissions were collected before and after the implementation. The results showed a 20-25% reduction in intersection delays, accompanied by an average of 15% decrease in CO2 emissions. Fuel consumption fell by 10% for cars and 15% for trucks. Traffic-light optimisation also improved the...

Comparative Analysis of the T1 Transit Procedure and TIR System: Institutional and Cost Efficiency Perspectives from Azerbaijan

Elvin Alirzayev, Nijat Karimov

Communications - Scientific letters of the University of Zilina X:X | DOI: 10.26552/com.C.2026.049  

The role and effectiveness of the T1 customs procedure in international transit transportation were examined in this study. It analyzes the legal framework, operational mechanism, and impact of the T1 procedure on logistics processes, while comparing its characteristics with the TIR system within the Common Transit (CT) framework. The findings demonstrate that the T1 procedure enhances customs control, reduces transit time and logistics costs, and strengthens risk management. Furthermore, the implementation of the New Computerised Transit System (NCTS) improves the transparency, traceability, and operational efficiency of transit operations, thereby...

Gender Differences in Visual Attention and Stated Preferences during Evaluation of Battery Electric Vehicles: An Exploratory Eye-Tracking Study

Viktória Cvacho, Radovan Madleňák, Alessandro Pagano, Edward Kozłowski

Communications - Scientific letters of the University of Zilina X:X | DOI: 10.26552/com.C.2026.050  

In this exploratory study were examined the gender differences in visual attention and stated preferences during the evaluation of battery electric vehicles (BEVs) using eye-tracking. Thirty-two participants (18 men, 14 women) viewed static images of the ten top-selling BEVs in Slovakia while eye movements were recorded across four predefined Areas of Interest (AOIs). Vehicle design attracted the greatest absolute dwell time in both groups. No gender difference reached conventional statistical significance (all p > 0.05), yet medium effect sizes were obtained for brand (d = 0.69), acceleration (d = 0.67), vehicle equipment (d = 0.60) and trunk capacity...