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In principle, every vehicle is equipped by a suspension system, which usually consists of springs and shock absorbers. The main purpose of the suspension system is to eliminate vibration of sprung and unsprung masses. Therefore, the proper operation conditions of the shock absorbers affect in a fundamental way total running properties of vehicles. However, during operation, shock absorbers are being worn out or they can even be damaged. Then, such a situation is unwanted and it has to be detected as soon as possible. The content of this article is focused on analysis of vehicles' shock absorbers defects. Methods for detection of possible shock absorbers faults are presented. Further, a proposal of the method for detection of a state of a hydraulic shock absorber during its operation is presented. The method uses identification of the temperature change of a hydraulic shock absorber during operation.

The paper presents an analysis and comparison of selected dynamic parameters in the common crossing and switch unit of a railway turnout. The paper includes a description of the measurement methodology, the report of mathematical methods used to evaluate the measured data and comparison of selected parameters describing dynamic processes in individual parts of the structure. The paper also includes a mathematical analysis of the lesser-known Hilbert Huang transformation, including its practical application. From the presented case study, practical experience and recommendations for the railway line managers, research organizations and possibly for the wider technical public are derived.

The article deals with method of purifying the exhaust gases in an automobile muffler or other transport equipment using electrical pulses. Electrical pulses are formed between the two ring electrodes (anode and cathode) installed in series along the gas flow. The physical picture of the process is described. A mathematical model has been developed and studied. A deterministic relationship has been established between the engine volume, the number of the crankshaft revolutions, the electric field strength and the charge strength and dynamic viscosity of the gas. Experimental studies have been carried out. The goal of the experiment was to confirm the hypothesis of impact ionization of exhaust gases. The effectiveness of electrical pulse purification has been proven.

Earthquake and tsunami preparedness is important to plan, especially in the earthquake and tsunami-prone areas, such as Banda Aceh. This study evaluates the tsunami evacuation routes' performance using the width of the road, travel time and the Degree of Saturation (DS) parameter. Some of the Degree of Saturation (DS) of the road segment surprisingly reach 1.0 to 3.18, exceeding the recommended 0.75 standard DS ratio. That indicates that the existing roads cannot accommodate traffic flow during evacuation. This study recommends the evacuation process by walking. Thus, developing the pedestrian routes according to evacuation safety requirements is strongly encouraged. Further, more escape buildings reachable within 15 minutes of evacuation time should be planned in the area. The pedestrian routes need to be designed separately from that of the traffic flow.

The article presents selected results and the sequencing of research into the project "Long-Term Monitoring of Rail Structures in Tramway Crossings with a Focus on Shallow-Grooved Crossings Aimed at the Optimization of their Maintenance and Noise Reduction", which was running with support from the Technology Agency of the Czech Republic within the Zeta Project (project registration No. TJ04000257) in 2020-2022. The project was elaborated jointly with the Prazska strojirna a.s. Company in cooperation with the Prague Public Transit Company (hereinafter PPTC). The project's objective was to optimize the maintenance of tramway tracks with a focus on shallow-grooved crossings in rail structures taking into account the noise emission levels during the life cycle of these crossings.

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 supply models were compared. The Just-in-Time model is characterised by costs that are spend on transportation. The Economic Order Quantity model includes costs of transportation and storage in a warehouse. After calculations, application of the Just-in-Time model in the given conditions was determined.

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 high impulsiveness tend to drive at high speed.

The article presents the results of the strength analysis of the chain binder components for symmetry fixing a wagon on the railway ferry deck, taking into account the actual hydrometeorological conditions of the navigation area. The simulation of the wagon dynamic load during the railway ferry rolling was carried out to determine the loads acting on the chain binder. The strength of the chain binder hook was analysed. The calculation results showed that the maximum equivalent stresses in the hook occur in the radial part and exceed the allowable ones by 23%. Therefore, to ensure the strength of the chain binder, it is necessary to comply with the appropriate roll angles of the railway ferry or create measures to reduce its load when rolling. The conducted studies will contribute to ensuring the safety of wagon transportation by sea and increasing the efficiency of rail-ferry transportation.

This article deals the implementation of a SiC MOSFETs in a three-phase inverter module, intended for use in auxiliary converters for powering electrical appliances of railway wagons. The basic properties of the SiC semiconductor elements and their differences, compared to IGBT modules, are summarized here. The given block diagram describes the individual blocks of the inverter module and their interconnection. Finally, a measuring setup for measuring the efficiency of inverters is presented. The measured efficiency values of the proposed SiC inverter and the original solution with IGBT modules are compared in the given graphs.

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 failure. The method makes it possible to solve a number of important technical and economic problems related to operation of units and ropeways, including the development of an optimal strategy for their planned repairs, which has a minimum cost.

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 article shows a fragment of the results of the author's concept of road safety management in Poland. The article shows the "program sequence" of the construction action of road safety management system in Poland. The main component of this "sequence" of actions to improve the road safety - should be the "road risk management model". It should be widely used in Poland as an element of knowledge and practices of international road safety management. It is primarily about the model of the Office for Land Transport Safety Authority in New Zealand adopted by the EU in its road safety policy. The article also presents other components of the author's concept, including the "3 levels" model of risk management, the idea of which is to isolate three categories of the risk associated with any transport system.

The 33.0 m long reinforced concrete bridge beams of the overpass superstructure after vehicular impacts were taken as a research object.
The overpass consists of 14 beams, six of which were repaired by restoring the widened lower part with EMACO FAST TIXO, manufactured by BASF.
The remaining 8 beams were completely dismantled and replaced with new ones. The new beams have been fully tested for the perception of vehicular loads. The fully reconstructed span structure showed compliance with the design loads of A14, NK-120 and NK-180 based on test results.

The main objective of our research was to map the exposure to electromagnetic smog in the frequented space of shopping centres in the city of Bratislava and to compare our results to the actual hygienic limits. The measurements of the low- and high-frequency electromagnetic fields were performed at different places in shopping centres. Our results did not exceed the Slovak current limits in any of the measurements. However, almost all of them markedly exceed new permitted limits according to EUROPAEM. Based on our results, stricter limits in many European countries and increasing evidence on possible harmfulness of long-term exposures to artificial electromagnetic fields, preventive carefulness can be recommended - to support the research in this field, to prepare professional public education and possibly to prepare the stricter Slovak exposure limits.

The aim of this research was to find out the specific geometrical parameters of the harmonic drive with the greatest impact on its lost motion. Harmonic drive units are widely used in production automation, robotics and automated manufacturing systems. Virtual model of Harmonic Drive was examined using the finite element method. The analyses were performed with considering the real test conditions of high precision gearboxes with a lost motion value of 4 % of the nominal output torque. The analyses' results were then used to develop a unique approach to obtain a functional relationship between the input parameters defining the shape of the flexspline and the harmonic drive lost motion value. Subsequently, the global sensitivity analysis was performed to determine the degree of influence of the selected flexspline parameters on the harmonic drive kinematic accuracy.

This study focuses on the issue of choosing a means of transport on the PilaWarsaw route by four groups of recipients. Representative sample consists of a student, a family with two children, a business client and a pensioner. The choice of the means of transport depends on various criteria resulting from the preferences of the users of the means of transport. The following criteria emerged from the survey results as a priority: transport time, transport cost, comfort and safety of travel, availability of means of transport, necessity or absence of transfers, cost of luggage transport and punctuality of means of transport. Selected preferences were assigned weightings based on the evaluation of a panel of experts in the field of expertise. In order to select the means of transport to implement the transport task, multi-criteria optimization method was used.

Present study evaluates the various congestion indexes in terms of speed performance index, volume to capacity ratio and congestion index based on travel time on the urban roadway network of 5.7 km in length, operating with mixed traffic conditions (traffic with varying static and dynamic characteristics of vehicles). The mitigations measures have been proposed to cater to the present traffic demand by converting the uncontrolled intersection to a partially controlled or signal-controlled intersection. In order to check the effectiveness of such mitigation measures, various scenarios have been generated in the developed and a well calibrated simulation model. It has also been observed that the speed performance index has improved by 8.88 percent while providing channelized intersection at one of the point elements and 11.52 %when the two-point elements have converted to channelizing intersection.

The article deals with the existing methods of cleaning vehicle radiators from sedimentary scale. A method of cleaning radiator tubes by ultrasonic radiation is proposed. An experimental bench has been developed for studying ultrasonic cleaning processes. Based on the results of the experiment, dependences have been obtained that determine the efficiency of the process depending on the mass of scale removed and the liquid outflow rate from the tubes. There are proposed the purification degree coefficients. The hypothesis about the possibility of cleaning radiators with ultrasonic vibrations has been confirmed.

The attractiveness of public transport is not high and therefore it is obvious that private transport is the preferred mode of transport. The interest in public transport has declined even more since the outbreak of the COVID-19 pandemic, during which passengers feared the rapid spread of the disease in public vehicles. As a result, the habit of traveling individually has increased. This paper highlights the massive increase in private transport in the V4 Countries by the use of private vehicles and the related decrease in use of public transport. It also presents some of the relevant tools of the Smart City concept that could improve the use of public transport in cities. This paper is aimed at highlighting the current use of public bus transport (including public transport) in the V4 countries vis-a-vis the ongoing COVID-19 pandemic and highlighting the information and communication technology (ICT) - related means of incentivization.

Pedestrian fatality rate plays a key role in examining effectiveness of the road safety. The present study attempts to examine the effect of various categories of accused vehicles and the average 85^th percentile speed at accident location on the pedestrian crash fatality. The study also attempts to develop pedestrian crash severity models using the binary logistic regression and boosted trees technique. Historical crash data, along with the video recording technique at accident sites, have been utilized for the present study. From regression equations, it is observed that when the heavy vehicle (HV) hits a pedestrian as compared to two-wheeler (2W), the average chance of death increases 2.44 times. According to the Boosted tree model, the contribution of speed is 60 %, whereas the contribution of category of accused vehicle is 40 % for pedestrian fatality prediction. The study should help in planning better strategies like all red time at intersections or pedestrian foot over bridge at critical locations.

Current crisis management approaches to protect soft targets make assumptions about average visitors/listeners/viewers or passengers. They do not give much consideration to impacts of diversity of potentially evacuated persons with regard to socio-psychological parameters/factors that may lead to practical problems and complications during the evacuation itself. At the same time, the soft target operators have various means of machine vision tools at their disposal, but do not use these records for more thorough analysis of evacuation planning needs. Based on this observation, the article identifies and analyzes the socio-psychological aspects that may significantly affect behavior and decisions of persons during the evacuation and thus total evacuation time.

The purpose of this paper was to determine the usability of unmanned hydrographic drones and photogrammetric techniques during the conduct of work, the results of which are potentially to serve as navigational materials in areas that, due to their characteristics, make it impossible to carry out research using crew vessels and direct shoreline determination. In order to prepare and carry out the measurement campaign with the greatest possible accuracy and safety, the authors of the article decided to determine the shoreline of the analyzed reservoir using photogrammetric methods. The use of satellite images allowed the border between land and water to be identified as precisely as possible, which had a direct impact on the accuracy of relating depth data to their location on Earth's globe. Use of unmanned vessels and orthophotos can find practical application when navigating vessels during maneuvers required high precision.

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 vehicles (less than 10 %) and spark ignition vehicles (almost 18 %). Considering costs, the largest difference between manufacturer's data and test data is observed, as in the previous case, in electric vehicles (0.25 €) and the largest in hybrid vehicles (almost 6 € per 100 kilometers driven).

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 and 0.99714 respectively. The results of this research add to the growing body of literature on traffic flow modelling and help urban planners and traffic managers in terms of the traffic control and the provision of convenient travel routes for pedestrians and motorists.

Concrete belongs to the most used building materials, applied in almost all types of constructions (civil, industrial, road, hydraulic, subway constructions, etc.). Currently, the most common is the vibration method of molding concrete and reinforced concrete products.

The long-distance travel (LDT) mode choice modeling is important for transportation planners. This study investigated alternative mode choice behavior for the LDT between the intercity buses and trains. A questionnaire survey, consisting of important mode choice attributes, was conducted on various groups of people in Bangladesh. Numerous travel mode choice contributing features (e.g., travel time, travel costs, origin-destination, comfort, safety, travel time reliability, ticket availability and schedule flexibility) were considered and the LDT mode choice models were developed using various machine learning algorithms typically applied for classification problems. With 95.31 % accuracy and 0.95 F1-score, Random Forest model was the best performing model for the dataset. According to the findings of this study, the intercity bus is preferred over the intercity train for LDT in Bangladesh.

The advantages and disadvantages of using the soft containers for cargo transportation are analyzed. The issues of the use of soft containers in transport and technological schemes for the supply of bulk goods are considered. Approaches to the rational selection of parameters of soft containers, during the transportation of bulk cargoes, taking into account the characteristics of the transported cargoes, are defined.

The term "Creative City" emerged in the 90s of the 20th century reflecting the trend of transforming post-industrial cities into new creative urban centres - bases for knowledge intensive firms, highly-skilled workers and major cultural assets. The concept of culture-based urban regeneration describes a scheme where culture is purposely employed as a vehicle for an overall urban and social revitalization. The paper addresses innovative processes within culture-based urban regeneration projects in three Slovak cities - Bratislava, Zilina and Kosice - under the concept of creative city. The focus is on the implementation of a tailor-made multi-factor knowledge management model with the aim of exploring the knowledge management practices in urban development projects dealing with the adaptive re-use of industrial and cultural heritage based on the non-profit bottom-up initiatives.

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) thresholds for Indian conditions. The thresholds are compared with existing guidelines provided by the HCM 2010 and AUSTROADS. In addition, the methodology for determining modification factors for applying HCM 2010 delay model in Indian traffic conditions is defined.

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.