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This article characterizes and presents Global Navigation Satellite Systems in relation to rail transportation applications. Due to the review character of this article, a synthesis of the literature discussing issues related to the possibility of implementing satellite positioning systems in the framework of their use in the management and control of railway traffic was made. On the basis of the literature review, the area of potential implementation of Global Navigation Satellite Systems was identified, as well as assumptions regarding the architecture of such systems being defined, along with the definition of criteria for assessing the impact of the use of satellite systems on rail traffic safety. The purpose of the above is to direct the development of rail guidance and control systems to systems that enable precise localization of rail vehicles, thereby optimizing the use of rail infrastructure through the implementation of efficient and cost-effective localization systems. This article goes on to characterize existing Global Navigation Satellite Systems and future directions related to the use of new satellite constellations. The basis of this review is the last twenty years of scientific publications on the subject of research issues related to the use of satellite positioning in railway systems. Based on the review of the state of the art and the results of the analysis, it was determined that the most frequently mentioned area of use of satellite positioning systems is the European Train Control System, the functionality of which enables the implementation of the transportation process based on so-called moving block spacing. The results of this review of the current state of knowledge will direct those responsible for the development and implementation of modern systems in the direction and control of railway traffic.

In the situation of the global SARS-COV-2 coronavirus pandemic, epidemic threats are dominant and ubiquitous. The article attempted to estimate the hazards of virus transmission in various transport services. In the author's opinion, numerous and very serious problems in the transport sector and transport services are in this case the result of a lack of a methodical approach to the problem of epidemic threats, including infection in a global epidemic. The paper presents a proposal for an original DHI method for assessing epidemic hazards in transportation services, taking into account various hazards and routes of virus transmission (droplet and contact) based on dedicated scales of hazard evaluation and multi-criteria assessment. This methodology is named Deep Hazard Identification (DHI). The primary stage of the methodology is the identification and estimation of transmission mechanisms of pathogen that can occur in transport services. For this purpose 15 criteria and weighting factors were defined and used for a multi-criteria epidemic hazards assessment. It enables the determination of the matrix of hazard assessment separately for the passenger transport and freight transport groups, which allows for the comparison of the DHI hazard factor between different transport services.

The analysis of human perception of vibrations in buildings is a critical aspect of structural engineering, particularly as urbanization intensifies and the proximity of vibration sources to buildings increases. This paper addresses the frequent errors in the assessment and diagnosis of the impact of vibrations on building occupants. Despite stringent standards and detailed methodologies, misinterpretations and incorrect implementations of these guidelines are common, leading to flawed diagnostic studies. These errors often stem from the misuse of measurement equipment, inappropriate selection of measurement points, and a general lack of comprehensive education on vibration analysis. National guidelines, although largely based on ISO standards, vary significantly, contributing to inconsistent practices across Europe. The dominant sources of urban vibrations include vehicle traffic, particularly heavy trucks and rail vehicles, which significantly impact both building structures and human comfort. This paper reviews the methodologies for measuring and interpreting vibrations, emphasizing the importance of correct sensor placement and data analysis. It highlights the necessity of integrating vibrational comfort into building design, considering both external and internal vibration sources. The study also explores the effectiveness of different evaluation methods, such as the RMS and VDV methods, and the impact of various weighting functions on the analysis results. The findings underscore the need for improved education and standardization in the field to ensure accurate assessments and enhance the vibrational comfort of building occupants.

The worldwide COVID-19 pandemic revealed societal challenges, with passenger transport rapidly experiencing the impacts of the virus and the evolution of the concept of safety in transport. Evaluating the likelihood of viral transmission within transportation systems may be a substantial challenge, considering the complex processes that influence the incidence of random transmission events. This paper introduces a method for determining the probability of pathogen transmission in public transport, focusing on the SARS-CoV-2 virus. The study draws on scenarios from the first and second waves of the COVID-19 pandemic in Poland, a period that was devastatingly marked by the lack of available vaccines. This study aims to add value to the scientific community by offering an estimation of the likelihood of SARS-CoV-2 transmission in public transport and a preliminary risk assessment for COVID-19 infection, considering the number of active, non-isolated COVID-19 cases in the Polish population. The potential of this approach was demonstrated through a comparison between two different categories of passenger transport in a city bus. Based on the presented case study and the calculated probability of pathogen transmission, it is estimated that the probability of SARS-CoV-2 infection during the second wave of the COVID-19 pandemic in Poland through the use of public transport was approximately 0.05%. Probability estimations based on elementary events, which can vary depending on the service category (for instance, the form of ticket purchase, availability of seating or standing places, or ticket inspection), can reveal even the smallest differences in the total likelihood of pathogen transmission. However, these minute individual variations significantly impact the total metrics calculated for daily users of public transport. For effective monitoring of potential epidemic threats and for designing suitable interventions and restrictions to lower the risk of future pandemics, it may be necessary to understand the role that transportation systems, particularly public transport systems, play in the spread of pathogens.

In recent decades, the dynamics of road vehicle traffic have significantly evolved, compelling traffic engineers to develop innovative traffic monitoring solutions, especially for dense road networks. Traditional methods for measuring traffic volume along road sections may no longer suffice for modern traffic control systems. This is particularly true for induction loops, a widely used method since the last century. In contrast, measuring techniques using microwaves or visible light offer better accuracy but are often hindered by the high cost of sensors. This paper presents new techniques for measuring traffic flow and other parameters that adapt to changing traffic dynamics using low-cost optical distance sensors. Our study demonstrates that the integration of multiple monitoring approaches enhances measurement accuracy, contingent on the dynamics and specific characteristics of the traffic. The results indicate that cheap optical distance sensors are particularly well suited for use in smart city road networks.

The paper presents a proposed methodology for designing and planning research on driver behavior at pedestrian crossings using whole-vehicle simulators. It was assumed that dedicated research should be conducted in specific problem contexts. The problems identified were the identification of hazards and the risk of accidents involving vulnerable road users. The purpose of this identification is to determine the determinants of safety at pedestrian crossings, which should constitute guidance when designing new solutions for safety support systems at pedestrian crossings. A number of hazard factors were identified; divided into categories, including types of crossings, location, and surroundings; behavior of vulnerable road users; and attention (focus) distractors, both inside and outside the vehicle. A method for defining and selecting research scenarios and selecting a group of research participants was proposed. Additionally, it was proposed to conduct repeatable test scenarios for different driving speeds and different weather conditions. With respect to the publications on this topic, this work focuses on the process of designing and planning dedicated simulation studies, which may provide a source of guidance and good practices for other researchers. This is an example of how interdisciplinary research involving human factors, traffic organization, and ITS systems can be planned and implemented.

This paper presents a description of the methodology developed for estimation of pathogen transmission in transport and the results of the case study application for long-distance passenger transport. The primary objective is to report the method developed and the application for case studies in various passenger transport services. The most important findings and achievements of the presented study are the original universal methodology to estimate the probability of pathogen transmission with full mathematical disclosure and an open process formula, to make it possible to take other specific mechanisms of virus transmission when providing transport services. The results presented conducted an analysis on the mechanisms of transmission of SARS-CoV-2 virus pathogens during the transport process, to examine the chain of events as a result of which passengers may be infected. The author proposed a new method to estimate the probability of transmission of viral pathogens using the probability theory of the sum of elementary events. This is a new approach in this area, the advantage of which is a fully explicit mathematical formula that allows the method to be applied to various cases. The findings of this study can facilitate the management of epidemic risk in passenger transport operators and government administration. It should be clearly emphasised that the developed method and estimated values are the probabilities of pathogen transmission. Estimating the probability of transmission of the SARS-CoV-2 virus pathogen is not the same as the probability of viral infection, and more so the probability of contracting COVID-19. Viral infection strongly depends on viral mechanisms, exposure doses, and contact frequency. The probability of contracting COVID-19 and its complications depends on the individual characteristics of the immune system, even with confirmed viral infection. However, it is undoubtedly that the probability of transmission of the SARS-CoV-2 virus pathogen is the most reliable measure of infection risk, which can be estimated according to the objective determinants of pathogen transmission.

Current awareness of epidemic threats and critical experiences of the COVID-19 pandemic require extension of the management model in the smart city, especially in the field of mobility and transport services, with monitoring of epidemic hazards. This paper addresses the issue of epidemic hazards, a new challenge in smart cities, and customer delivery services. The novel DHI methodology for epidemic hazards assessment is presented and applied to compare customer delivery services in aspects of SARS-CoV-2 epidemic hazards. The case studies presented a detailed analysis of epidemic hazards on the basis of process algorithms and dedicated quantitative scales to assess factors influencing the mechanisms of virus transmission. The developed DHI methodology and the results obtained for transport services constitute important cognitive knowledge for the administrative personnel in smart city.

Public transport during COVID-19 has been crucial in ensuring the safety and health of both passengers and staff while maintaining essential public transport services. Currently public transport is gradually resuming its operations, the pandemic's influence is expected to persist for a long time. The vast majority of studies in this aspect concern the likelihood of spreading the virus inside the means of transport during travel. Nevertheless, there exists a substantial body of articles addressing the manner in which passenger movement within public transport systems has been impacted by the safety concerns and altered satisfaction levels following the propagation of the pandemic. This paper presents a model that accurately represents how passengers move through different parts of a public transport system, such as a bus or train station and stops. This model takes into account factors like how long it takes for passengers to board and exit a vehicle, how they move through different parts of the stops, and how their movements are affected by factors like crowding and delays. To reduce the risk of transmission on public transport focused on bus stops areas, the research paper formulated a passenger flow model using simulation programs like PTV Vissim and FlexSim with assumptions on minimum distance and concept of area cross sections. These programs were used to simulate passenger exchange scenarios, using data collected from real data. The paper aimed to develop a passenger exchange model that could reduce the risk of infection. By understanding the passenger flow model and how passengers interact with the public transport system, we can implement effective measures to minimize the spread of COVID-19 and other infectious diseases.

The impact of transport-induced vibrations on people is a particularly important problem. Sudden or intensifying vibration phenomena of a local nature may compromise safety, especially in transport. The paper addresses the results of research on the impact of spring stiffness parameters on the propagation of vibrations in the vehicle structure using simple amplitude and frequency measures. The use of the developed method of selective multi-criteria analysis of frequency bands made it possible to compare the vibrations recorded in the vehicle with a new or worn coil spring. The results of the present study allow the development of a large data base in which all signals are classified by the exploitation parameters and location of the propagation of vibration in the vehicle. The most important findings and achievements of the presented study are the testing of actual suspension components with real damage under controlled conditions, the identification of the vibration propagation path from the wheel to the driver and passenger feet, the quantitative comparison of vibrations affecting humans in the vehicle (through the feet), and the frequency decomposition of vibration for selected bands. These findings improve the proper interpretation of the developed measures and, as a result, the difficulties in using this knowledge at the engineering level, for example, in the design and construction improvement stage. Therefore, innovation points and engineering significances are a method of selective multi-criteria analysis of frequency bands and have potential applications in diagnostics and the design of suspension systems and in terms of passengers’ comfort.

The article provides a discussion on a methodology intended for testing of power transmission systems featuring an innovative highly torsionally flexible metal clutch patented by the co-authors of this paper. What this methodology takes into account is the amplitude and frequency analyses discussed in the article, as well as a sensing system based on diverse piezoelectric and magnetic phenomena, the Doppler effect, etc. Both contact and non-contact (laser measurement) methods were used during the tests. The purpose of the tests conducted at the stand, originally designed by the authors in accordance with the methodology proposed, was to evidence that using the innovative and patented, highly torsionally flexible metal clutch makes it possible to reduce the vibrations of multi-stage toothed gears, consequently reducing the forces affecting the gear bearings and those acting at the tooth space, which is to enable the service life of individual components of the power transmission systems intended for mining scraper conveyors to be significantly extended. Based on the studies and analyses performed by the authors, one can observe and conclude that the methodology proposed in the paper makes it possible to use an example of a relatively complex power transmission system in order to examine the relationships between the processes at work, i.e., the decline of the linear vibrations of the gear housing (which is undoubtedly positive in power transmission systems) at the expense of increasing torsional vibrations of the innovative clutch, the latter not to be considered unfavourable to users in the case analysed.

The purpose of this research paper is to present the application of the developed sound method as a supporting tool to deal with railway traffic flow control. It is found that controlling railway line occupancy is the main issue associated with railway traffic flow. For this purpose, the line occupancy control based on a sound method has been developed. The concept of using sound waves as a source of information about approaching people, animals, vehicles, etc., has been known for centuries, and is due to the natural properties of the sense of hearing. There are many engineering attempts on the use of this phenomenon, which are mostly based on applications of distributed fiber-optic sensing technology. This paper presents the results of the sound pressure measurement in the immediate proximity of the rail to analyze and evaluate the use of the acoustic wave as an information carrier on approaching rail vehicles. The purpose of this research is to discuss the sound method introduced here, and apply it in different circumstances.

In this present paper, the dynamic stiffness method (DSM) was formulated to investigate the out-of-plane natural vibration of a thin orthotropic plate using the classical plate theory (CPT). Hamilton’s principle was implemented to derive the governing differential equation of motion for free vibration of the orthotropic plate for Levy-type boundary conditions. The Wittrick–Williams (W–W) algorithm was used as a solution technique to compute the natural frequencies of a thin orthotropic plate for different boundary conditions, aspect ratios, thickness ratios, and modulus ratios. The obtained results are compared with the results by the finite element method using commercial software (ANSYS and those available) in the published literature. The presented results by the dynamic stiffness method can be used as a benchmark solution to compare the natural frequencies of orthotropic plates.

The paper presents how an important aspect of introducing new machines, especially in the mining industry, is testing a prototype under laboratory conditions. For this purpose, advanced methods of analyzing the vibrations of a drive system equipped with an innovative prototype of a flexible torsion clutch are presented. The main goal is to present a comprehensive method for analyzing vibration signals in various dimensions of the signal analysis. As a result of this approach, it can be seen how much important information about the tested clutch can be obtained by using various analysis methods in terms of time–frequency distributions or order analysis. To emphasize the differences in the functioning of the tested clutch and the possibility of monitoring these differences on the basis of the observation of residual processes, such as vibrations, the results for the flexible and locked clutch are compared.

The purpose of this research was to analyze the possibilities for the application of vibration signals in real-time train and track control. Proper experiments must be performed for the validation of the methods. Research on vibration in the context of transport must entail many of the different nonlinear dynamic forces that may occur while driving. Therefore, the paper addresses two research cases. The developed application contains the identification of movement and dynamics and the evaluation of the technical state of the rail track. The statistics and resultant vector methods are presented. The paper presents other useful metrics to describe the dynamical properties of the driving train. The angle of the resultant horizontal and vertical accelerations is defined for the evaluation of the current position of cabin. It is calculated as an inverse tangent function of current longitudinal and transverse, longitudinal and vertical, transverse, and vertical accelerations. Additionally, the resultant vectors of accelerations are calculated.

This article presents results of tests of the effect exerted by technical condition of shock absorbers on the braking efficiency of an automotive vehicle. The tests were conducted using Fiat Seicento featuring front shock absorbers which enabled shock-absorbing fluid-level adjustment. The tests comprised measurements conducted on the shock absorbers in four states, i.e. the nominal state with the fluid level at 100%, with shock-absorbing fluid levels of 25%, 50% and 75% as well as with the fluid tank completely empty (0%). Road tests of braking efficiency were conducted on cobbled pavement by means of a decelerometer.

This article provides a discussion of the results of studies on the original system condition monitoring of a three-stage transmission with a bevel–cylindrical–planetary configuration installed in an experimental scraper conveyor. Due to the high vibroactivity of gear transmissions operating under the impact of a scraper conveyor’s chain drive, these unwanted effects of machine operating vibrations were assumed to be applied. For purposes of the study, vibrations were measured on the driving transmission housing in an idling scraper conveyor. The main purpose of the study was to establish the frequencies characteristic of the gear transmission, and to determine whether it was possible to run vibroacoustic diagnostics of the same transmission under conditions with a considerable impact of the conveyor chain. An additional cognitively significant research goal was the analysis of the dependence of the diagnostic utility of the signal depending on the sensor mounting point. Five different locations of three-axis sensors oriented to the next stages and various types of gears were determined, as well as places characterized by high spatial accessibility, which are often selected as places for measuring the vibration of gears. Using MATLAB software, a program was written that was calibrated and adapted to the specifics of the measuring equipment based on the collected test results. As a result, it was possible to obtain a multidimensional data interpretation of vibration signals of system condition monitoring of a three-stage gear transmission operating under difficult conditions. The results were based on signals registered on the real three-stage gear transmission operating under the impact of a scraper conveyor’s chain drive.

Safety of the railway transport is extremely important issue, thus it has to be supported by numerous of terms. It is not only the legislation and organization or traffic control but also the proper quality of every devices in the railway infrastructure. The paper deals with safety in the rail industry. Companies and producers of railway equipment have to guarantee the best quality, maintenance and reliability. Safety is also a device directly responsible for protecting e.g. level crossings but also safety in terms of design and construction. . Supervision of products is fulfilled in Poland by e.g. the Office of Railway Transport managing the safety and regulation of rail traffic. The paper presents industry security in terms of product as safety in design and production, in construction, in exploitation. Despite such extensive, multisector and multifaceted organizational, legal and technical safety structures in rail transport it is advisable to conduct further research into the analysis of the possibilities for improved safety. Also authors have assumed that for the improving of railway crossing safety level the support system for the traffic detection can be developed. To increase of the complex crossing safety level the support system has to be independent from current usage control devices, as axle counter block. Thus the paper presents concept of application of vibration wave propagation employing as source if information on train or car detection.

This article presents the results of studies on the impact of acoustic waves on geophones and microphones used to measure airblasts carried out in a reverberation chamber. During the tests, a number of test signals were generated, of which two are presented in this article: frequency-modulated sine (sine sweep) waves in the 30–300 Hz range, and the result of detonating 3 g of pyrotechnic material inside the chamber. Then, based on the short-time Fourier transform, the spectral subtraction method was used to remove unwanted disruption interfering with the recorded signal. Using MATLAB software, a program was written that was calibrated and adapted to the specifics of the measuring equipment based on the collected test results. As a result, it was possible to clean the signals of interference and obtain a vibration signal propagated by the substrate. The results are based on signals registered in the laboratory and made in field conditions during the detonation of explosive materials.

The paper presents the design solutions and fastening mounting frames in special vehicles. Special Vehicles is an interesting and growing market in the production of heavy vehicles. Due to the nature of the use of these vehicles of their design solutions require constant change and adaptation, which opens up the possibility of a utilitarian research

The article presented part of the guidelines used for the modification of special purpose vehicle bodies. For example brand vehicles are details about the possibility of limiting the extension of the vehicle overhang, weight distribution, etc., and construction methods used in practice when extending the overhang of the vehicle. Describes the applicable rules for different technologies, ie. riveting, bolting, welding used in the modification of the frame.

Vibration phenomena occurring in vehicles are very relevant for safety and comfort. Passenger car must be considered as a multi-technical system in which there are non-linear phenomena. Therefore, vibrations occurring in vehicles should be analyzed in many points of car structure and relate them to other criteria analysis. The paper presents examples of the results of vibration and their distribution at selected points during laboratory research and road tests.

The paper presents assessment of the impact of the processes handling efficiency on the transport process based on research done in the real object, using same technologies and material handling equipment. The aim of the paper was to confirm importance of loading and unloading processes of palletized cargo as an initial and final link of multimodal transport by developing methods’ proposal for monitoring and assessing the effectiveness of cargo operations as well as development of measures and comparison estimators. The analysis of the manipulation operations’ duration throughout the transport process is based on the percentile rates of manipulation and carriage in total transport process duration and the percentage of manipulating time in the duration of the carriage. These indicators and examined loading and unloading times, are the basis for the development of scheduling algorithms for optimizing transport processes on the scale of the whole transport chain. This data is also a helpful input to support strategic decisions on the allocation of financial resources for the development of infrastructure and terminal equipment, warehouses and other facilities.

The results of the examination of a vehicle suspension system in the plate position are presented in the paper. The model vehicle is a Fiat Seicento with front independent suspension, McPherson type, with the steering system and with the semi-trailing arm in the rear suspension. Identification of the model was made by comparing the simulation results with the results from the test stand. A multibody model of the vehicle will be used in studies of the impact of shock absorber technical conditions on the dynamics of automotive vehicles.

This paper presents results of the modern vehicle shock absorbers’ researches on indicator test stand. On this stand can be determined the diagrams of force versus displacement and force versus velocity. These diagrams can be determined for changeable strokes and constant velocities or the opposite way round. In researches the modern hydraulic twin-tube vehicle shock absorber was modificated and the changes of oil volume were possible. There was determined the influence of oil volume changes on force versus displacement and force versus velocity diagrams. On the basis of force versus velocity diagrams, the dumping characteristics were determined (value of force for maximum velocity on this diagram). The influence of oil volume changes on dumping characteristics was determined too. The results of this investigation can be used in simulation researches of vehicle suspension dynamic.

The paper presents results of vibro-acoustic signal analysis (acceleration of the unsprung mass of passenger’s car suspension actuated to vibration by harmonic, kinematic vibration). The range of research has included front shock absorber for Fiat Seicento with simulated fault (oil leak). Force process consisted of three phases: increase of frequency, vibration with constant frequency (above 21 Hz) and decreases of frequency.For the analysis process Short Time Fourier Transform method was used with superposition of rectangles window and with zero complement method. On STFT spectrum resonance frequency of unsprung mass was identified. The estimator was the means of maximum acceleration amplitude peak in frequency band round resonance frequency. The result of investigation was presented on diagrams with changeable value of estimator for different technical conditions of shock absorber (with different volume of oil inside the shock absorber)

The paper presents possibilities of applying linear decimation procedure in frequency analysis of non-stationary signals. It shows the results of analytical experiments conducted with vibration signals registered during examination of car suspension which was activated to vibration on harmonic stand research. Working cycles identification algorithm was helpful to make LDP of working cycles parts of a signal. Signals spectrum results confirm amplitude selectivity for typical frequency ofresearching dynamic system.

The article provides a discussion on the studies comprising active experiments conducted on selected structural elements of vehicles, the purpose of which was to analyze the vibration propagation in vehicles construction. The vibration excitation was achieved by applying an engine working on idle gear. The studies were conducted on vibration propagation for different constant rotational velocity. The changes of the signals were observed in time, frequency and simultaneously in timefrequency domains.