Communications - Scientific Letters of the University of Zilina, 2022 (vol. 24), issue 2
Operation and Economics in Transport
Methods of Comparison of the Economic Order Quantity and Just-in-Time Restocking Technologies. The Case Study
Andrii Galkin, Velerii Levada, Volodymyr Kyselov, Oksana Hulchak, Dmytro Prunenko, Iryna Voronko
Communications - Scientific Letters of the University of Zilina 2022, 24(2):A35-A43 | DOI: 10.26552/com.C.2022.2.A35-A43 
Estimation of the optimal size of order is one of the key tasks in determining the parameters of the urban freight restocking system. The existing analytical models and methods are considering each technology separately and they do not compare the Economic Order Quantity (EOQ) and Just-in-tme (JIT) restocking technologies. The purpose of this research was to evaluate efficiency of the JIT and EOQ restocking technologies. The research would help in selecting the delivery model, analyzing functioning of existing JIT and EOQ models. The article presents an approach to determining the comparison in organizing supplies to the retailer. For this, the two...
Analysis of the Operating Costs of Passenger Cars Declared by Vehicles' Manufacturers and Obtained by Users
Piotr Gorzelańczyk, Bartlomiej Kelm
Communications - Scientific Letters of the University of Zilina 2022, 24(2):A44-A52 | DOI: 10.26552/com.C.2022.2.A44-A52
Every year, there are more and more cars on the roads that cause pollution. To reduce it, conventional vehicles have started to be replaced by electric and hybrid vehicles. Therefore, the average fuel/energy consumption of electric, hybrid, spark ignition and self-ignition vehicles over a test distance of 100 km was investigated. The test results were then compared to the manufacturer's data and the average difference between the manufacturer's data and the test data is shown. The largest average difference in fuel consumption between the manufacturer's data and the test data was observed for hybrid vehicles (over 230 %) and the smallest for electric...
Supply and Demand Analysis of a Free Floating Bike Sharing System
Cristian Poliziani, Joerg Schweizer, Federico Rupi
Communications - Scientific Letters of the University of Zilina 2022, 24(2):A53-A65 | DOI: 10.26552/com.C.2022.2.A53-A65
This article presents an analysis of the supply and demand of a FFBSS recently implemented in the city of Bologna, Italy. The main aspects treated in this paper are: analysis of bike availability; temporal analysis of FFBSS demand; calibration and validation of a novel model that predicts the number of daily trips per available bike. This model is based on a linear combination of several day attributes, including meteorological and day-type attributes. Moreover, an origin to destination analysis is generated showing the spatial distribution of FFBSS trips. The methods are applied to a scenario with almost a million GPS traces recorded between July...
The Importance of Connecting the First/Last Mile to Public Transpor
Alica Kalašová, Kristián Čulík, Miloš Poliak
Communications - Scientific Letters of the University of Zilina 2022, 24(2):A66-A78 | DOI: 10.26552/com.C.2022.2.A66-A78
The first and last mile part of the public transport journey are essential for the whole transport system. Its quality affects the overall experience of the passenger in public transport. It is not important how attractive are individual transport modes if the rest of the journey is unattractive for the passenger. This paper is about shared mobility and it describes the connection between the first/last mile and the public transport system. Modes of shared mobility can reduce the pressure on the city transport system. It can also bring a better modal split. The authors performed a traffic-sociological survey for processing the respondents' opinions...
Do Smaller Firms Grow Faster than Large Enterprises? The Case of Czech Transportation and Storage Industry
Roman Fiala, Veronika Hedija
Communications - Scientific Letters of the University of Zilina 2022, 24(2):A79-A87 | DOI: 10.26552/com.C.2022.2.A79-A87
The study is focused on the relationship between firm growth and firm size. The aim of this study is to examine the growth-size relationship and test Gibrat's law validity in the Czech transportation and storage industry. To examine the relationship between firm size and firm growth, the linear auto-regression model is applied. The sales and sum of total assets are used as indicators of the firm size. The final sample contains data for more than 6,000 Czech firms in the period 2008-2017. The results have shown that Gibrat's law is not valid in the Czech transportation and storage industry. Smaller firms tend to grow faster than larger ones. Due to...
Mechanical Engineering in Transport
Comparative Study of Residual Stress Prediction Methods in Additive Manufacturing Processes
Suyambazhahan Sivalingam, Sunny Narayan, Sakthivel Rajamohan, Ivan Grujic, Nadica Stojanovic
Communications - Scientific Letters of the University of Zilina 2022, 24(2):B99-B105 | DOI: 10.26552/com.C.2022.2.B99-B105
The additive manufacturing (AM) of products involves various processes, such as raising the temperature of a work-piece (part) and substrate to the melting point and subsequent solidification, using a movable source of heat. The work piece is subjected to repeated cycles of heating and cooling. The main objective of this work was to present an overview of the various methods used for prediction of the residual stresses and how their contributions can be used to improve current additive manufacturing methods. These novel methods of manufacturing have several merits, compared to conventional methods. Some of these merits include the lower costs, higher...
Modeling the Reliability Indicators' Kinetics of a Mobile Ropeway Formed by the Self-Propelled Units
Alexander Lagerev, Igor Lagerev
Communications - Scientific Letters of the University of Zilina 2022, 24(2):B106-B119 | DOI: 10.26552/com.C.2022.2.B106-B119
A promising type of cargo vehicles are mobile ropeways formed by autonomous self-propelled rope units connected by a common cable transport system. The article presents a method for predicting the kinetics of the reliability indicators of the ropeway as a whole, individual rope units and their subsystems, taking into account the timing and volume of planned repairs. This method is advisable to use at the design stage of rope units, as it allows one to simulate the stage of their operation and provide the required level of reliability based on proactive replacement of structural elements that have reached the maximum permissible probability of critical...
Experimental Investigations of Injection and Combustion Parameters of a Homogeneous Charge Compression Ignition (HCCI) Engine with a Multi-Injection Common Rail System
Waleed Niklawy, Moatasem Shahin, Mohamed I. Amin, Ali Elmaihy
Communications - Scientific Letters of the University of Zilina 2022, 24(2):B120-B134 | DOI: 10.26552/com.C.2022.2.B120-B134
This work experimentally investigates the most imperative parameters that control the injection and combustion processes in a multi-injection HCCI Diesel engine namely; fuel-line pressure, timing of multi-injection events and the resulting in-cylinder pressure. These parameters in addition to the heat release rates are evaluated at different engine loads and speeds over up to 42 successive cycles. The main inter-relations of these parameters are also discussed.
The Impact of Road Irregularities on the Motion of a Motor Vehicle during Acceleration
Jarosław Zalewski
Communications - Scientific Letters of the University of Zilina 2022, 24(2):B135-B147 | DOI: 10.26552/com.C.2022.2.B135-B147
In this paper the selected results concerning the analysis of the phenomena occurring between the road and the wheels of a motor vehicle have been presented. The analysis was prepared for the simulation of the acceleration maneuver with the 100 % (full) throttle along the road with various conditions. The aim of this paper was to analyze whether both the full throttle and the road conditions may affect the forces occurring in the contact area between the wheels of the vehicle and the road, regarding the road conditions and the rear wheel drive of the analyzed vehicle's model.
Durability Analysis of the Prototype Test Rig for Main Rotors
Karol Ścisłowski, Krzysztof Skiba, Mirosław Wendeker, Rafał Kliza, Ksenia Siadkowska, Tomasz Lusiak, Andrej Novák
Communications - Scientific Letters of the University of Zilina 2022, 24(2):B148-B157 | DOI: 10.26552/com.C.2022.2.B148-B157
This paper presents an analysis of the strength of a prototype test rig for testing rotors of unmanned aerial vehicles. Digital design software was used for the design work that covered the creation of a virtual model of the test rig and strength analysis of its key elements. The paper discusses the test rig solutions, applied to date, of the small main rotor research. From the assumed operational parameters and structural parameters of the rotor, the main forces acting on the designed structure were determined: lifting force, reaction torque and empty mass of the test rig. Suitable actuators of the control system enabling the regulation of the total...
Electrical Engineering in Transport
Mathematical Models of Effective Topology of Computer Networks for Electric Power Supply Control on Railway Transport
Oleksandr Stasiuk, Valeriy Kuznetsov, Vitalii Zubok, Lidiya Goncharova, Antonina Muntian
Communications - Scientific Letters of the University of Zilina 2022, 24(2):C27-C32 | DOI: 10.26552/com.C.2022.2.C27-C32
The paper is devoted to analysis of modern directions of innovation-investment formation of intelligent computer networks that control the fast-moving technological processes of electricity supply. It is based on the conclusion that the problem of increasing the productivity of information exchange between information resources and consumers is dominant. A method for increasing the efficiency of information exchange is proposed as a search for the rational location of a new node and the organization of such a set of its connections among the whole set of nodes of the computer network, which provides a minimum average topological distance. Mathematical...
Path Planning Algorithm Based on Teaching-Learning-Based-Optimization for an Autonomous Vehicle
Ahmed D. Sabiha, Mohamed A. Kamel, Ehab Said, Wessam M. Hussein
Communications - Scientific Letters of the University of Zilina 2022, 24(2):C33-C42 | DOI: 10.26552/com.C.2022.2.C33-C42
This study provides a teaching-learning-based optimization (TLBO) path planning method for an autonomous vehicle in a cluttered environment, which takes into account path smoothness and the possibility of collision with nearby obstacles. The path planning problem is tackled as a multiobjective optimization in order to plan an efficient path that allows the vehicle to travel autonomously in crowded settings. The TLBO algorithm is used to find the ideal path, with the goals of finding the shortest path to the target site and maximizing path smoothness, while avoiding obstacles and taking into account the vehicle's dynamic and algebraic properties.
Civil Engineering in Transport
Freight Fleet Management Problem: Evaluation of a Truck Utilization Rate Based on Agent Modeling
Ganna Samchuk, Denis Kopytkov, Alexander Rossolov
Communications - Scientific Letters of the University of Zilina 2022, 24(2):D46-D58 | DOI: 10.26552/com.C.2022.2.D46-D58
The article deals with the problem of estimating the rational number and utilization rate of the vehicles' fleet. According to the analysis results of the state-of-the-art literature it has been revealed that the issue of substantiating the rational fleet size and the rate of its utilization were not fully solved. The purpose of the study was to increase the efficiency of servicing transportation orders by determining the required number of vehicles. The goal of the research was the influence of the transportation process parameters on the truck utilization rate. Originating from the probabilistic nature of the transportation process, it has been proposed...
Structural Behavior of Prestressed Concrete Bridge Girder with Epoxy Joint
Assylkhan Jalairov, Dauren Kumar, Khaini-Kamal Kassymkanova, Zeynep Sarsembekova, Gulzhan Nuruldaeva, Gulnar Jangulova
Communications - Scientific Letters of the University of Zilina 2022, 24(2):D59-D71 | DOI: 10.26552/com.C.2022.2.D59-D71
The study object is a prototype of a composite bridge prestressed concrete beam with a length of 42.0 m for road bridge desks for perception of impact from motor vehicles in the form of A14, NK-120 and NK-180 loads.
Causes for the Change Orders in Road Construction: Reviewed from Owner
Mega Waty, Hendrik Sulistio
Communications - Scientific Letters of the University of Zilina 2022, 24(2):D72-D84 | DOI: 10.26552/com.C.2022.2.D72-D84
Changes in road construction are affected by the owner and contractor at the beginning, middle, or end of the project. This study aims to determine the ranking of the factors that cause change orders for road construction from the owner's point of view. Data was collected by distributing questionnaires and interviews to project owners. Reliability and validity tests involving 32 respondents resulted in 48 causes of change orders. This study quantifies the relative importance of the factors that cause change orders and shows the ranking of factors and groups that cause change orders according to their level of importance for causes of change orders....
Contribution of Daily General Mobility to pm10 Concentration Development in Sisak-Moslavina County, Croatia during the Covid-19 Pandemic in 2020
Teodor B. Iliev, Tea Sikirica, Darko Špoljar, Renato Filjar
Communications - Scientific Letters of the University of Zilina 2022, 24(2):D85-D91 | DOI: 10.26552/com.C.2022.2.D85-D91
Carbon and pollutant emissions drive climate change and affect health and daily life. The Covid-19 pandemic created an unprecedented opportunity to understanding the impact of carbon and pollutant emission. In this paper were identified Telecommunications records-derived general mobility indices as contributors to the PM10 pollutant concentration development in industry-intensive Sisak-Moslavina County, Croatia, during the Covid-19 outbreak in 2020. Time-series of daily mean PM10 concentrations and mobility changes indicators are analysed for their statistical properties identification, decomposed, and the decomposing components examined for association...
Modification in Hcm Delay Model for Roundabout for Mixed Traffic Conditions - a Pilot Study
Asir Khan, Ashish Dhamaniya, Shriniwas Arkatkar
Communications - Scientific Letters of the University of Zilina 2022, 24(2):D92-D104 | DOI: 10.26552/com.C.2022.2.D92-D104
Roundabouts have proven to be an effective intersection design method for smooth traffic flow movements and improved safety. Previous studies show that VISSIM, commercial traffic simulation software, can be used as a proficient tool for modeling and efficiently analyzing roundabouts. This paper focuses on developing a methodology for modeling roundabouts in India using VISSIM. Three typical roundabouts were chosen from the northern part of India. Calibration and validation of the model were performed to ensure the correctness of the model. The average delay and volume to capacity ratio (v/c ratio) were compared for developing the level of service (LOS)...
Management Science and Informatics in Transport
Traffic Simulation with Open-Source and Commercial Traffic Microsimulators: A Case Study
Nelson Baza-Solares, Ruben Velasquez-Martínez, Cristian Torres-Bohórquez, Yerly Martínez-Estupiñán, Cristian Poliziani
Communications - Scientific Letters of the University of Zilina 2022, 24(2):E49-E62 | DOI: 10.26552/com.C.2022.2.E49-E62
The analysis of traffic problems in large urban centers often requires the use of computational tools, which give the possibility to make a more detailed analysis of the issue, suggest solutions, predict behaviors and, above all, support efficient decision-making. Transport microsimulation software programs are a handy set of tools for this type of analysis. This research paper shows a case study where functions and limitations of Aimsun version 8.2.0, a commercial-like European software and Sumo version 1.3.1, a European open-source software, are presented. The input and output data are similar in both software and the interpretation of results is...
Importance of the Static Infrastructure for Dissemination of Information within Intelligent Transportation Systems
Jiří Jelínek, Jiří Čejka, Josef Šedivý
Communications - Scientific Letters of the University of Zilina 2022, 24(2):E63-E73 | DOI: 10.26552/com.C.2022.2.E63-E73
Intelligent transportation systems (ITS) are a today´s hot topic, especially in the context of the development of information technologies, which can be employed in transportation. Although the scope and the technical solution of these systems may vary, they are frequently based on VANET (Vehicular ad hoc network), i.e. a communication network, which is primarily generated among the moving subjects, which form ITS. Given the highly dynamic VANET, the questions are raised as to the data transmission. This paper is aimed to make a detail analysis of the communications within VANET using the simulation model, which includes the static infrastructure of...
Prediction of Vehicular Traffic Flow Using Levenberg-Marquardt Artificial Neural Network Model: Italy Road Transportation System
Isaac Oyeyemi Olayode, Alessandro Severino, Tiziana Campisi, Lagouge Kwanda Tartibu
Communications - Scientific Letters of the University of Zilina 2022, 24(2):E74-E86 | DOI: 10.26552/com.C.2022.2.E74-E86
In the last decades, the Italian road transport system has been characterized by severe and consistent traffic congestion and in particular Rome is one of the Italian cities most affected by this problem. In this study, a Levenberg-Marquardt (LM) artificial neural network heuristic model was used to predict the traffic flow of non-autonomous vehicles. Traffic datasets were collected using both inductive loop detectors and video cameras as acquisition systems and selecting some parameters including vehicle speed, time of day, traffic volume and number of vehicles. The model showed a training, test and regression value (R2) of 0.99892, 0.99615...
Assessment of Reliability of the Transport Information Systems
Boris Zhelenkov, Irina Safonova, Yakov Goldovsky, Alexander Abramov, Nataliya Tsyganova
Communications - Scientific Letters of the University of Zilina 2022, 24(2):E87-E95 | DOI: 10.26552/com.C.2022.2.E87-E95
In this paper is given the definition of e reliability of a transport information system, with features of transport information systems listed. Equations for calculating reliability indicators are given, as well. The developed hierarchical graph model for assessing the reliability of transport information systems and an algorithm for analyzing the graph model, which allows taking into account the specifics of the reliability of the operation of system elements at different levels of the hierarchy, are presented. Using the graph model and the graph model analysis algorithm, it is possible to reasonably predict the strategy for the creation and development...
Safety and Security Engineering in Transport
Measuring of Braking Distances of Firefighting Trucks
Ladislav Jánošík, Ivana Jánošíková, Jiří Kuczaj, Pavel Poledňák, Izabela Šudrychová, Martin Tomášek, Josef Vlček
Communications - Scientific Letters of the University of Zilina 2022, 24(2):F1-F13 | DOI: 10.26552/com.C.2022.2.F1-F13
The paper addresses the driving dynamics of emergency fire trucks. It focuses on the issues of braking, measuring real braking distances and calculating adhesion coefficients. It presents the results of measuring the real braking distances for firefighting vehicles - type water tenders. Measurements were taken on dry asphalt and depending on the vehicle's speed of travel. Experiments were conducted on five types of firefighting vehicles. The results of measurements are mainly used by fire protection units to the drivers' self-education to improve safety when driving to intervene.
Analysis of Pedestrian Behavior in the City of Pila
Piotr Gorzelańczyk, Jakub Bazela, Tomáš Kalina, Martin Jurkovič
Communications - Scientific Letters of the University of Zilina 2022, 24(2):F14-F26 | DOI: 10.26552/com.C.2022.2.F14-F26
Every year, many people lose their health and/or lives on Polish roads. One of the reasons for this is behavior of pedestrians at pedestrian crossings, which affects the road safety. The aim of the article was to conduct experimental research, the idea of which was to study the behavior of pedestrians at pedestrian crossings in the city of Pila, the results of which can be applied to Poland. During the research, the behavior of pedestrians and the impact on the probability of a road accident were analyzed. Undoubtedly, the prevailing epidemic, during which people are in many respects limited, had an impact on the results obtained, therefore the number...
The Effect of Boredom Proneness, Impulsiveness and Sensation Seeking to Driver Speeding Behavior
Leksmono Suryo Putranto, Anissa Noor Tajudin, Sunu Bagaskara
Communications - Scientific Letters of the University of Zilina 2022, 24(2):F27-F35 | DOI: 10.26552/com.C.2022.2.F27-F35
Speeding or driving above the speed limit might be conducted due to various reasons. This paper is intended to investigate whether there are certain underlying behaviors that trigger speeding in the various driving environment. Authors were investigating the effect of boredom proneness, impulsiveness and sensation seeking on driver speeding behaviors. They received 676 responses to our distributed online questionnaires mainly from Lampung, East Java, East Borneo, North Celebes and North Moluccas. A Structural Equation Modelling (SEM) was conducted for analysis. The result implies that the drivers with high sensation seeking, low boredom proneness and...
Application of Data Mining Algorithm to Investigate the Effect of Intelligent Transportation Systems on Road Accidents Reduction by Decision Tree
Mohammad Mehdi Khabiri, Fatemeh Matin Ghahfarokhi, Sara Sarfaraz, Hasan Mohammadi Anaie
Communications - 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...