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Evaluating Port Performance in EU Countries with Fuzzy and Grey LogicGül Aliºar Kayar, İlker İbrahim AvºarCommunications - Scientific Letters of the University of Zilina 2026, 28(1):A1-A18 | DOI: 10.26552/com.C.2026.011 Ports are fundamental components of global supply chains, and their performance is critical to sustaining international trade and economic activity. Recognizing that existing studies often focus on individual ports rather than broader regional patterns, a new hybrid Multi-Criteria Decision-Making (MCDM) model is proposed to provide a more comprehensive assessment framework. Based on expert judgments, the Fuzzy Analytic Hierarchy Process (AHP) results indicate that cargo type is the most influential determinant, followed by cargo direction and container volume. Using Evaluation based on Distance from Average Solution - Grey (EDAS-G) and Additive Ratio Assessment - Grey (ARAS-G), the port performance across 24 EU countries for the period 2014-2023, incorporating a temporal dimension that enables multi-year trend analysis. The hybrid grey-based ranking shows that Italy, Spain, the Netherlands, and Germany rank the highest, while Slovenia, Bulgaria, Malta, and Cyprus consistently rank at the lower end. |
Solution to the Chicken-Egg Dilemma of Electric Mobility for Indian Cities: A Roadmap to Clean EnergyRuchi Singhal, Apurvkumar Desai, Chetan R. PatelCommunications - Scientific Letters of the University of Zilina 2023, 25(4):A147-A163 | DOI: 10.26552/com.C.2023.066 Since the electrical vehicles (EVs) are infrastructure-dependent technology, their penetration faces the problem of lacking recharging infrastructure. Thus, there is a dilemma of chicken-egg in the penetration of EVs and their charging infrastructure for the decision-makers. The article examines the e-mobility scenario of 3 Indian cities to understand issues and challenges in implementing EVs. The study suggests a co-diffusion strategy for the EVs and charging infrastructure. Firstly, the priority EV segment has been decided based on the transport mode preference. Then, suitability of charging facilities according to the segment of the EVs has been presented by analyzing the turnover rate and time spent at several places. The study recommends policies on the upfront cost of EVs, charging infrastructure, awareness generation and others, while leveraging the existing government schemes like Atmanirbhar Bharat and FAME-II. |
Dynamic Routing with Static Delivery Time Windows in Urban Last-Mile Transport LogisticsViktor Danchuk, Oleksandr Hutarevych, Stanislav Popov, José Vicente Busquets-MataixCommunications - Scientific Letters of the University of Zilina 2026, 28(1):E1-E12 | DOI: 10.26552/com.C.2026.001
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Characteristics of Changes of Transportation Performance for Pairs of Critical EdgesPeter Czimmermann, Michal KohaniCommunications - Scientific Letters of the University of Zilina 2018, 20(3):84-87 | DOI: 10.26552/com.C.2018.3.84-87 When the robustness of a public service system design is tested, we can often use scenarios where possible random failures can occur and they can influence the time the service is accessible which is provided for system users. The construction of a suitable scenario is based on the choice of links of the transportation network which influence the system performance in a substantial way. In such scenarios one or multiple arcs can be affected by this failure. In our contribution we present characteristics of pairs of critical arcs that can be used to develop an algorithm for the creation of critical scenarios. |
Indonesian Aviation Act 1/2009: An Examination and the Quest for Reform in Certain IssuesAdhy Riadhy Arafah, Rosa Ristawati, Kautsar Ismail, Gerlyana Shafa Putri HardrianiCommunications - Scientific Letters of the University of Zilina 2025, 27(2):A27-A39 | DOI: 10.26552/com.C.2025.030 Indonesian Aviation Act 1/2009, which has been adopted for more than 14 years ago, was made to accommodate the ICAO's Universal Safety Oversight Audit Programme (USOAP) findings in 2007, which highlighted the need for legislative changes to reduce air transport accidents in Indonesia. The Act regulates two aspects of aviation activity, covering the public and private. The public sector regulates aircraft activities in Indonesia's airspace, certain issues are missed owing to (the) controversy over its legal terminology. In the private sector, the jurisdiction issue and applicability of the Act have consequently regarding the applicability of the Montreal Convention 1999 was ratified by Indonesia in 2016. In this paper were examined some provisions in the Act by normative juridical and comparative approaches, emphasizing the urgent need for legal reform. It is ultimately recommended to amending the Act to align it with current conditions. |
Methodology for Assessing the Key Operational Efficiency Indicators for Removal and Shunting Operations of Shunting LocomotivesGabit Bakyt, Aizhan Makhanova, Murat Mussabekov, Galymzhan Ashirbayev, Malik Zhamankulov, Kuantkhan Sarsenov, Aisha MussabekovaCommunications - Scientific Letters of the University of Zilina 2025, 27(4):B250-B260 | DOI: 10.26552/com.C.2025.048 The problem dealt with in this article is the methodology of the key performance indicators (KPI) evaluation of shunting locomotives operation when performing hauling and shunting work. The main parameters affecting the efficiency of rolling stock operation are described, including performance, fuel efficiency and locomotive utilization rate. The algorithm of KPI calculation is proposed, based on the analysis of operational data and statistical methods is proposed. According to the analysis of the trend in cargo transportation over the past 3 years, the need to develop a methodology for evaluating the key performance indicators of shunting work is justified. A comparative analysis of various approaches to assessing the operational performance of locomotives is carried out, their advantages and disadvantages are revealed. Practical recommendations for improving the operational performance of rolling stock are described. |
Improving the Energy Efficiency of the Explosive Pulse during Drilling and Blasting Operations to Increase the Quality of Crushing and Conditions for Conveyor Delivery of Overburden Rocks in Quarries and SectionsTasbulat Monbolovich Igbaev, Nurlan Asylkhanovich Daniyarov, Adilbek Kazbekovich Kelisbekov, Arsen Zakirovich AkashevCommunications - Scientific Letters of the University of Zilina 2025, 27(2):B96-B108 | DOI: 10.26552/com.C.2025.024 Widespread application of advanced transportation technologies in conditions of open-pit mining with the use of high-capacity belt conveyors is limited by the need for additional crushing of overburden rocks and minerals. Accordingly, the quality of crushing of rock mass, the output of oversize during drilling and blasting operations at quarries and open-pit operations significantly affect the possibility of using flow and cyclic-flow technologies with the use of conveyor transport. In this paper is presented a method of increasing the energy efficiency of the explosive pulse in drilling and blasting operations by means of developed gas pedal designs to improve the quality of crushing and conditions of conveyor delivery of rock mass. |
Evaluation of Bus Lane Implementation Expediency on Streets with Different Lane Numbers: Case StudyFuad Dashdamirov, Turan VerdiyevCommunications - Scientific Letters of the University of Zilina 2026, 28(1):D1-D12 | DOI: 10.26552/com.C.2026.003 The introduction of bus lanes on streets may not be feasible from the standpoint of reducing the overall time loss for road users. The goal of this study was to develop a method for checking the effectiveness of bus lane implementation. Using simulation experiments, conducted in PTV VISSIM, for a different number of traffic lanes, the speeds of buses and vehicles were determined both when buses are moving in the general flow and after the introduction of a bus lane, at different values of flow intensity and bus frequency. Regression equations, describing the dependence of speed on the traffic flow intensity and frequency of buses for different numbers of traffic lanes, are formulated. A mathematical model has been developed to calculate and compare the time losses of road users before and after the introduction of a bus lane, based on determining the average speed of traffic flow and buses. |
Preparation of Big Data Sets for Optimization of Intercity Freight Driver SchedulesOlexandr Melnychenko, Myroslav Oliskevych, Nazar KhomynCommunications - Scientific Letters of the University of Zilina 2026, 28(2):A48-A61 | DOI: 10.26552/com.C.2026.022 The problem of using big data for optimal planning of work and rest of truck drivers in intercity freight transportation is considered. The problem is solved for a team of drivers in compliance with the EU regulation 561/2006. The proposed data preparation can reduce the practical computational complexity and find the optimal driver work schedule. The clustering of the initial data was substantiated for optimizing schedules based on the criterion of compatibility of transport orders. The compatibility of orders follows from the analysis of similarity of two consecutive transportation processes performed by one driver during his/her work shift. Simulation modelling was performed. The influence of the scale of the territory on the quality of the prepared initial data was also investigated. A rational range of the compatibility coefficient for the high-quality preparation of a large data set was substantiated. |
Transport Efficiency Strategies in Assembly Workplace: A Case StudyDariusz Plinta, ¥uboslav Dulina, Beáta Furmannová, Ján ZuzikCommunications - Scientific Letters of the University of Zilina 2024, 26(3):B187-B198 | DOI: 10.26552/com.C.2024.035 In this article, improvements in assembly workplace layouts in an industrial context are investigated to enhance productivity and efficiency. The installation of the Cleaner M300 device is focused on, existing layout challenges are identified, and targeted improvements are proposed. Data collection, analysis, and real-world experimentation are employed to evaluate current workplace conditions and potential enhancements, including material flow dynamics and transport cart utilization. Proposed solutions are aimed at streamlining assembly processes, minimizing material transportation time, and boosting operational efficiency. The effectiveness of these improvements is validated through qualitative feedback from workers and supervisors. The importance of improving workplace design to enhance manufacturing operations, increase productivity, and improve transport efficiency is underscored by the study. |
Energy-Saving Thermal Stabilization System and Assessment of Temperature Loadings of a Bridge Deck PavementSergey A. Kostenko, Aleksandr A. Piskunov, Nikita A. Ganin, Galina A. EmelianovaCommunications - Scientific Letters of the University of Zilina 2022, 24(3):D141-D149 | DOI: 10.26552/com.C.2022.3.D141-D149 To improve the general traffic safety in conditions of winter ice at traffic interchanges and to extend the overall service life of the roadway, it is proposed to use energy-saving thermal stabilization of a bridge deck pavement by transferring the low-temperature geothermal energy by heat pumps. The practical and computational parts of the pilot plant work are demonstrated and discussed. In order to analyze the need to use additional thermal joints, computer simulation was performed in the LIRA-CAD-2018 software package with subsequent extrapolation to a real bridge span. |
Application of Data Mining Algorithm to Investigate the Effect of Intelligent Transportation Systems on Road Accidents Reduction by Decision TreeMohammad Mehdi Khabiri, Fatemeh Matin Ghahfarokhi, Sara Sarfaraz, Hasan Mohammadi AnaieCommunications - Scientific Letters of the University of Zilina 2022, 24(2):F36-F45 | DOI: 10.26552/com.C.2022.2.F36-F45 Due to the large amount of available data in this study, authors have utilized data mining algorithms, especially the decision tree, to process these data and obtain the information, which would result in increasing road safety, determining the causes affecting it and patterns leading to traffic accidents. The effective use of this tool and its role in controlling the number of driving accidents is the subject of this study with the help of data mining algorithms. The results show that the increase in the number of roadside assistances to more than 41; number of driving accidents (fatally injured) is not significantly different, hence one of the proposed strategies for intelligent relay stations and its organization with the intelligent transportation tool is available. The intelligent transportation system utilities comprise of monitoring, guidance and enforcement tools, plus service tools such as rescue, driver assistant and road improvement. |
The GPS / EGNOS Positioning Quality in APV-1 and LPV-200 flight proceduresGrzegorz Grunwald, Adam Cieæko, Kamil Krasuski, Rafa³ Ka¼mierczakCommunications - Scientific Letters of the University of Zilina 2021, 23(2):E23-E34 | DOI: 10.26552/com.C.2021.2.E23-E34 Accuracy, integrity, continuity and availability are the basic quality parameters extremely important in satellite navigation. The article presents results of research using the European Geostationary Navigation Overlay Service (EGNOS) that belongs to the group of Satellite Based Augmentation Systems (SBAS). The measurement data adopted for analysis were recorded in years: 2012, 2014, 2015, 2017 and 2018 in the north-eastern Poland. Results of the analysis showed a significant reduction in the maximum GPS / EGNOS positioning error values from 2014 onwards (compared to results from 2012). In general, values of parameters characterizing accuracy, integrity and availability meet the requirements for EGNOS applications in APV-1 and LPV-200 aviation procedures. It the case of continuity the requirements are not met. |
The Costs of Charging Electric Vehicles in PolandEwelina Sendek-Matysiak, Hubert RzêdowskiCommunications - Scientific Letters of the University of Zilina 2022, 24(1):A1-A11 | DOI: 10.26552/com.C.2022.1.A1-A11 The very important factor that influences the decision of those interested in buying a vehicle is its operating costs. This paper determines the costs of driving 100 km for various electric vehicles, charging service providers and chargers, which was then confronted with the costs of refueling. Based on the analysis carried out, it was determined that, at present, the lowest costs of fueling/charging of a vehicle in Poland are connected with use of an electric vehicle, but only when the charging is performed with use of public AC chargers. Moreover, it was determined that the savings that will result from charging electric vehicles at AC charging stations as compared to filling up internal combustion engine vehicles are small and do not compensate for the purchase price of an electric vehicle. |
The Use of Recycled Concrete Powder as Supplementary Cementitious Materials for Manufacturing ConcreteOussama Douidi, Ahmed Tafraoui, Abdelkadir Makani, Pedro SernaCommunications - Scientific Letters of the University of Zilina 2024, 26(2):D27-D37 | DOI: 10.26552/com.C.2024.019 Construction development is inevitable, while despite its advantages and its benefits, it may lead to several problems related to landfill and its storage, referring to the high volumes of concrete waste currently generated annually, almost 2.0 ton/per capita according to Eurostat. In Algeria, the government has integrated waste management strategy [3] provision to recovering 60 % of construction waste by 2035, which can translate to an urgent need to find innovative ways to recycle concrete waste. One is using those wastes to produce aggregates; however, around 20 % of those aggregates represent fines, wich can lead to several issues if not considered in the concrete mixture. This work is an investigation that allows for using this fine fraction as partial replacement of cement. The result confirms the feasibility of using this material efficiently by applying an optimization process, ensuring an optimal cement replacement percentage. |
Relationship between the Transport Performance and Financial Coverage in Urban Public Transport in the Czech RepublicJosef Kubík, Tomá¹ UrbánekCommunications - Scientific Letters of the University of Zilina 2024, 26(4):A65-A74 | DOI: 10.26552/com.C.2024.042 The research presented aimed to compare the transportation performance, as measured by vehicle kilometers, to the operating costs incurred by thirteen transport companies in the Czech Republic from 2010 to 2019. This period was chosen to ensure that our research is not affected by the Covid-19 pandemic. The financial coverage of operating costs includes revenues from fares and compensations from city budgets. We utilized data from the annual reports of The Association of Transport Companies of the Czech Republic. Based on the obtained data, we confirmed a positive relationship between the city's population, the extent of transportation performance, and consequently, the total operating costs. |
Bibliometric Overview of Current Trends in Maritime Transport: The Issue of a Special Interest in Delivery of a Consignment as a Tool to Achieve Sustainability of International TransportJarmila Sosedová, Martin Jurkoviè, Alena Molnárová Baracková, Jana Majerová, Piotr Gorzelanczyk, Ondrej StopkaCommunications - Scientific Letters of the University of Zilina 2024, 26(1):A11-A21 | DOI: 10.26552/com.C.2024.008 The sustainability of international transport remains a critical topic of concern in both theory and practice. Ideally, scientific literature should align with practical needs, but such concurrence is not always present. This disparity is also evident in the specific issue of consignment delivery, which is currently of a great practical importance but lacks sufficient coverage in scientific literature. This paper aims to analyse current trends in maritime transport and their relevance to achieving global sustainability in international transportation. Additionally, it seeks to compare these findings with the practical needs and requirements of the industry, in order to provide constructive recommendations for further research. To accomplish this objective, a bibliometric analysis was conducted using scientific databases, including Web of Science and/or SCOPUS. |
Generalized Ordered Logit Model with Testing Assumptions: A Case Study of Using Urban Light Rail in BursaNurten Akgun, Tiziana Campisi, Muhammed Talha SunarCommunications - Scientific Letters of the University of Zilina 2024, 26(3):D38-D51 | DOI: 10.26552/com.C.2024.028 Logistic regression has been a widely used prediction technique to analyze categorical variables. However, if the assumptions are violated the results may be biased. The study in this paper applied an analytical technique namely generalized ordered logit model. A case study of using urban light rail under pandemic conditions was applied for the analysis. The results suggested that logistic regression should not be applied before exploring the multicollinearity and applying the test of parallel lines. If the assumptions are violated, generalized ordered logit model should be considered. Regarding the predictive variables, sociodemographic, socioeconomic and travel pattern, related variables were found to have a statistically significant impact on the perception of safety and infrastructure of urban light rail. The outcomes of the study would provide a deeper understanding of developing regression models for categorical variables for future studies. |
Vulnerability Assessment of Transport Infrastructure Elements - Case Study in RajecJozef Kubás, Boris Kollár, Jozef Ristvej, Katarina Petrlová, Kateøina Bla¾kováCommunications - Scientific Letters of the University of Zilina 2024, 26(4):F23-F35 | DOI: 10.26552/com.C.2024.040 The risk assessment of the area, with emphasis on the transport infrastructure, is dealt with in this paper. Disruption of some elements of transport infrastructure can lead to major negative impacts on the functioning of society, economies or states. The article therefore starts with presentation of the characteristics and importance of the road transport infrastructure with regard to its vulnerability. The core of the paper is the identification of vulnerable elements of road transport infrastructure and their parts and the subsequent vulnerability assessment of the selected element of the road transport infrastructure in the selected area. Therefore, the aim of the research, presented in this paper, was to propose a method for identifying and assessing the vulnerability of road transport infrastructure elements using the latest approaches in the field of vulnerability assessment. The proposed vulnerability assessment procedure is applied in the conditions of the city of Rajec in Slovakia. |
The Strength Calculation of the Modernized Brake Lever Transmission for a Wagon BogieSergii Panchenko, Juraj Gerlici, Alyona Lovska, Vasyl RavlyukCommunications - Scientific Letters of the University of Zilina 2025, 27(2):B109-B117 | DOI: 10.26552/com.C.2025.027
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Studies on Compressive Strength Microstructural Analysis of Self-Compacting Mortar with BacteriaMiddela Sravanthi, S. Venkateswara Rao, Kanthala Krishnaveni, Venkata Kamal Lal Meenuga, Sujana KarivedaCommunications - Scientific Letters of the University of Zilina 2022, 24(4):D183-D200 | DOI: 10.26552/com.C.2022.4.D183-D200 This research proposed bacteria-treated concrete, which is highly desirable because the mineral precipitation induced from microbial activities is pollution free and natural. This study investigates the effects of Bacillus Licheniformis, Bacillus Cohnii and mixed bacteria on compressive strength, ultrasonic pulse velocity test, rapid chloride penetration test, microstructural analysis and bacteria cell concentration of 10 5cell/ml of normal and self-compacting mortars made with and without fly ash for 7 and 28 days. With self-compacting mortar, the compressive strength of Bacillus Licheniformis improved by 30.3 % and by adding Bacillus Cohnii in 28 days, the ion penetration value decreased. Finally, it was observed that the deposition of calcium carbonate in mortar improved compressive strength using SEM-EDS and XRD with compound polymorphisms of calcite, vaterite, quartz, and Hautirite. |
Developing a Speed-Based Congestion Severity Index Using the Clustering Technique for Developing CountriesMalaya Mohanty, Satya Ranjan Samal, Kundan SamalCommunications - Scientific Letters of the University of Zilina 2025, 27(2):D67-D75 | DOI: 10.26552/com.C.2025.020 A novel approach for traffic congestion assessment has been presented using percentile speeds as key indicators, focusing on urban roads. By evaluating the 98th, 85th, and 15th percentile speeds, authors of the research developed a congestion severity index, offering a more precise and intuitive method for analyzing traffic flow compared to traditional travel time-based indices. Key congestion indices, such as the Planning Time Index (PTI) and Travel Time Index (TTI) were compared to percentile speeds, revealing a significant association with the 15th and 85th percentile speeds. The K-means clustering technique was applied to classify congestion severity into three levels, validated by a high silhouette value indicating the robust clustering. The study's speed-based congestion severity index provides a practical and efficient framework for real-time congestion management, particularly in heterogeneous traffic environments. |
Increased Interest in Military Tourism on Selected Examples from the Area of Northern and Northeastern PolandAleksandra Zienkiewicz, Tomasz Podciborski, Rafal Ka¼mierczakCommunications - Scientific Letters of the University of Zilina 2021, 23(4):G38-G50 | DOI: 10.26552/com.C.2021.4.G38-G50 Military tourism is one of the forms of tourism that is not sufficiently researched throughout Poland. It is only in recent years, after the period of political transformation, that interest in this phenomenon has been growing every year. This research has aimed to indicate the possibilities of military tourism development in northern and northeastern Poland. It includes an analysis of data concerning the Naval Museum in Gdynia, the "Wolf's Lair" Fortress in Gierloz and an example of a military event - an air show, which took place on the premises of the 44th Airborne Museum in Gdynia. Results of the analysis of the military tourism development in northern and northeastern Poland indicate that military sites and military-themed events attract considerable tourist traffic and play an important role in the overall development of tourism. |
Improving the Energy Efficiency of Operation of a Multi-Motor Plate Conveyor in the Steady-State Operation ModeAdilbek Kazbekovich Kelisbekov, Nurlan Asylkhanovich Daniyarov, Baurzhan Gilymovich MoldabaevCommunications - Scientific Letters of the University of Zilina 2024, 26(2):C1-C8 | DOI: 10.26552/com.C.2024.022 The established mode of operation of the conveyor with a nominal linear load is the most economically advantageous from the point of view of increasing the energy efficiency of mineral transportation, in which the cargo flow with minerals corresponds to the nominal productivity of the conveyor. An increase in the linear load of the working branch of the traction-bearing body to a nominal value reduces the share of unproductive consumption due to which energy savings are achieved for a certain period of time, characterized by its hourly average value. |
Factors Negatively Affecting the Quality of Work of Pti Technicians - the Case of the Slovak RepublicJuraj Hudec, Branislav ©arkanCommunications - Scientific Letters of the University of Zilina 2024, 26(4):A89-A104 | DOI: 10.26552/com.C.2024.054 The authors examine the negative impact of objective and subjective factors on the quality of work of periodical technical inspection stations (PTI) technicians. In this context, the authors conducted a survey among the PTI technicians and vehicle operators. From the results formulated in the article, it emerged that the quality of PTI technicians' work, and thus the entire PTI, is negatively affected mainly by the high degree of subjectivity entrusted to PTI technicians, when evaluating the technical condition of vehicles (94.12 %) and the resulting scope for incorrect judgments and influencing the result of PTI (corruption, acquaintances), and the approach of PTI owners (influencing technical inspections results due to fear of losing customers, pressure on quantity over quality, method of rewarding the PTI technicians, etc.). The authors also propose some measures to improve the quality of PTI activities. |
Carpooling in Transport in Today's ICT - Based EconomyPaulina Wi±czek, Iryna Sitak, Alena Novak Sedlackova, Andrej Novak, Martin BugajCommunications - Scientific Letters of the University of Zilina 2025, 27(4):A48-A59 | DOI: 10.26552/com.C.2025.052 The purpose of this research was, among other things, to show that the carpooling model can be regarded as a manifestation of collective intelligence and a response to the crisis of sustainability in today's ICT-based economy, which makes carpooling services a cheaper alternative to transportation services provided by other modes of transport: train and bus. The main research problem is contained in the question: How do collective intelligence and the tenets of sustainability influence the popularity of carpooling and the lower cost of carpooling services, compared to those provided by other forms of transportation? The critical literature analysis method, the comparison method and the statistical method, among others: the Mann Whitney U test and the Kruskal Wallis ANOVA test, were used in implementation of the study. |
The Research of the Engine-Reducer Assembly in the Traction Transmi̇Ssi̇on SystemAyaz Abdullaev, Ilham Huseynov, Israil Elyazov, Elchin Yusifzade, Ramin Abdullaev, Allahverdi SharifovCommunications - Scientific Letters of the University of Zilina 2025, 27(3):B237-B249 | DOI: 10.26552/com.C.2025.045 During the movement of the train in various operational regimes, a series of deficiencies arise in the mechanical components, which depend on kinematic and parametric factors affecting the working conditions of the traction drive. An innovative traction drive is discussed in this article, which prevents the non-uniform distribution of parametric factors, as well as dissipative, inertial, and elastic characteristics along the length of the track. |
Mathematical Modelling of Hybrid Powertrain Systems for Improved Energy EfficiencyOleg Lyashuk, Victor Aulin, Roman Rohatynskiy, Ivan Gevko, Andriy Gypka, Dmytro Mironov, Volodymyr Martyniuk, Artur Lutsyk, Nadia DenysiukCommunications - Scientific Letters of the University of Zilina 2025, 27(2):C36-C52 | DOI: 10.26552/com.C.2025.028 The development and simulation of a mathematical model for a hybrid powertrain vehicle, aiming to optimize its energy efficiency and dynamic performance is presented in this study. Implemented in MATLAB/Simulink, the model captures the dynamic interactions between the hybrid system's components, including the internal combustion engine, electric motor, and battery. By conducting a full factorial experiment, the specific power of the hybrid vehicle was analyzed, revealing the critical influence of factors such as driving speed, road gradient, and battery state of charge. The proposed model demonstrated a discrepancy of 4-11% between the simulated and experimental results, confirming its adequacy for forecasting energy consumption and operational range. These findings offer valuable insights for enhancing the hybrid vehicle performance and sustainability through precise energy management strategies. |
Assessment of the Quality Indicators of the Carriage Movement by Directly Measuring the Forces of Interaction between the Wheels and RailsOleksij Fomin, Pavlo ProkopenkoCommunications - Scientific Letters of the University of Zilina 2024, 26(3):B155-B166 | DOI: 10.26552/com.C.2024.030 This work describes the features and methods of measuring the forces of interaction between the wheel pairs and rails by measuring wheel deformations at control points. The work also contains recommendations for direct measurements of the forces of interaction between the wheels and rails to determine the actual margin of stability of wheel pairs from derailment. The result of the work is general requirements for the system of direct measurement of the strength of interaction of the high-speed rolling stock wheel pairs with rails and scientifically based recommendations for direct measurement of the interaction forces of wheels and rails. The problems of interaction between the wheel pairs and rails do not significantly depend on the track width and are general in nature for different countries of the world. |
The Methodology to Evaluate a Rescue and Training Phantom for the Road Rescuing Organized by Police Officers as Exemplified by Crash KellyPawel Gromek, Mariusz NepelskiCommunications - Scientific Letters of the University of Zilina 2021, 23(3):F83-F95 | DOI: 10.26552/com.C.2021.3.F83-F95 The paper presents a methodology to evaluate a rescue and training phantom for road rescuing organized by Police officers. The methodology is exemplified by the Crash Kelly phantom, static and dynamic functionalities of which seem to be more frequently implemented in the road safety training processes. It stems from a morphological analysis, focusing on the quality of rescue activities, emergency resources' adequacy and the training levels. In addition, experts' evaluation allows to examine phantoms using 6 practically determined criteria, expressing their strengths and weaknesses in analysed context. |
