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The research presented in this article consisted of analysis of the ship structural accidents at low temperatures and the effect of carbon percentage in various classifications of carbon steel, compared to the high tensile strength steel materials. The objective of this research was to fill the knowledge gap by expanding the understanding of the influence of low temperature, material, and structure on the axial compression test of tubes. The simulations as idealization of the compression test were conducted with variations in temperature, material carbon percentage, and geometry shape, using Finite Element Analysis (FEA). The results showed that at -100 °C, the material had the best ability to resist compression energy; high carbon steel had the highest strength at various carbon percentages, and the square geometry showed the best ability to absorb energy before failure.

The automobile cable systems for loading and unloading operations between the vehicle-support and vehicle-vehicle points are presented in this paper. The scheme of the automobile mobile cable system is based on a two-cable cableway. Based on this scheme, the parameters of the movement of goods by automobile cable systems are substantiated at variable parameters: mass m artificial loads together with the mass of the frame structure: 35 ≤ m ≤ 95 (kg); the angle of inclination α pairs of parallel ropes to the horizon: 10 ≤ α ≤ 15 (°); tension force ropes 2400 ≤ T_D ≤ 5000 (N). It has been established that the dominant effect on the minimum time T has angle α, then mass m and tension forces T_D ropes. At the same time, it is worth noting that the range of discrepancy of the quantities T values, when the above factors change, is insignificant and is close to 5,7 % for (m/α) and 6,6 % for (T_D/α).

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.

The research presented in paper has focused on design of the transportation evacuation during a special flood caused by an accident at a water structure using GIS-enabled network analysis. Freely available population and address point data were used to calculate the number of residents at risk. Three scenarios of time required for each evacuation activity were determined using the PERT method, and the time required for evacuation was determined using a Gantt chart. The approach proposed in the paper is suitable for obtaining relatively quick results that can be taken into account when preparing for crisis events. The results of the case study proved that the evacuation can be carried out in the necessary time, but revealed possible shortcomings of the proposed approach. These shortcomings are discussed along with possible alternative solutions and other factors influencing the evacuation planning process.

This study conducts an in-depth exploration into the principal factors that influence the reliability of specialized rail cars and auto-rail vehicles. It places a particular emphasis on key performance metrics including the average operational duration prior to failure, the proba¬bility of faultless operation, the rate of failure, and the gamma-percentage resource. Addition¬ally, the paper examines various methodologies for computing these metrics and quantitatively evaluating their respective values. It elucidates how specific units of electromechanical equip¬ment, which operate in conjunction with asynchronous motors and clutches, exhibit distribution patterns during failure that overlap between exponential and normal distributions. The study further presents a mathematical formula to approximate the reliability density of the distribution, a critical factor in recalibrating the metrics associated with specialized rail cars.

This research was conducted to investigate the current state of transportation, as well as the transportation costs of the residents of towns with affordable residential houses, by preparing and presenting a questionnaire to these residents. In this questionnaire, things like housing costs, the amount of travel to the city center, satisfaction with public transportation services and its variety, easy access to public transportation and required places, the amount of use of public transportation and private vehicles were examined and solutions to reduce transportation costs were presented. Although the price of housing in the towns is lower than in the city center; the costs of transporting the residents of these towns are significant. In addition, the state of public transportation and access to needed places is unfavorable, so that about 60 % of the interviewees were dissatisfied with public transportation services.

E-rickshaws, as emerging transport modes, notably affect mixed traffic flow on urban roadways. To evaluate their influence relative to other vehicle types, this study aim was to determine the Passenger Car Unit (PCU) value for e-rickshaws, as the Indian Roads Congress has yet to assign one. Three analytical methods were used: Chandra’s method, the homogeneous coefficient method, and multiple linear regression. Data were gathered via three-hour video recordings at three different locations, each in Hapur and Sonipat. Using VLC media player, vehicle speeds and counts were extracted for analysis. The data were then processed in SPSS and Excel to derive equivalency values and assess influencing factors. Results indicate that the e-rickshaw’s PCU value increases with rising traffic speed, but decreases with higher e-rickshaw concentration. Additionally, when the traffic volume increases, but composition remains unchanged, the PCU value for e-rickshaws shows a declining trend. These findings can help to refine the traffic flow modelling in heterogeneous conditions.

A genetic algorithm (GA) is an optimization technique based on natural genetics, using selection, crossover, and mutation. Crossover combines genetic material from two parents to create offspring, maintaining diversity and preventing premature convergence. While the two parents are typically used, multi-parent crossover, involving more than two parents, has shown superior results. in this paper is explored the multi-parent crossover in dual genetic algorithms, which facilitate information exchange between populations through interpolation crossbreeding. Offspring inherit traits from both parent populations, improving adaptability. The Cave-Surface GA (CSGA) with three-parent crossover is tested on 15 Travelling Salesman Problem (TSP) benchmarks. Results show that the CSGA outperforms both traditional GAs and two-parent CSGA. This method demonstrates great potential for complex optimization challenges.

Nowadays, many modern vehicles contain a lot of systems for autonomous functions or driver assistance systems (traffic sign recognition). Modern vehicles contain many embedded systems and control units (also for signal and image processing), so implementation of deep learning or AI-based algorithms is possible. In older vehicles, mentioned systems missing or they are limited. In this paper is presented a design of algorithm for detection of selected regulatory traffic signs to extend the selected autonomous or intelligent functions of older vehicles. Algorithm is based on shape and color detection of key features of selected regulatory traffic signs (amplification of specified color pixels and Generalized Hough Transformation). This algorithm can be easily implemented or used in many other applications, such as for driving mobile or robotic platforms. Detection efficiency of algorithm is also evaluated in this paper.

In this study was investigated the effect of a novel surface treatment technique, called laser ablation or laser surface cleaning (LSC), on the electrochemical properties of AZ80 magnesium alloys. Its effect on corrosion resistance was compared to conventional techniques represented by grinding and polishing. The corrosion stability of the produced surfaces was determined by potentiodynamic (PD) polarization tests and electrochemical impedance spectroscopy in 0.1M NaCl. The results showed that the LSC process produced a regular, uniform surface morphology. Although the LSC treatment led to the passivation of the AZ80 surface, the overall corrosion resistance was compromised compared to surfaces treated by grinding and polishing.

Speed humps are used to reduce vehicle speeds and enhance the road safety. However, there has been very limited study that discusses the Level of Service (LOS) that a speed hump provides to its road users. The present study attempts to designate LOS for movement on speed humps based on user perception. A perception-based survey in google forms was collected to assess the opinions of daily commuters while moving over speed humps along their regular routes to work which comprised various socio demographic and technical factors along with recommendations and suggestions. The study employed clustering technique to determine the Level of Service range. The results offer valuable insights into the effectiveness and acceptance of speed humps as a traffic calming measure for enhancing the road safety and could serve as a basis for potential improvements in speed hump design and implementation.

The article deals with the power analysis of semiconductor devices nowadays commonly used in perspective traction inverter topologies suitable for automotive industry applications.  The power analysis is devoted to topologies, which are the Voltage Source Inverter (VSI) topology and perspective three-level alternatives, which are the Neutral Point Clamped (NPC) and T-type Neutral Point Clamped (T-NPC) traction inverter topologies. The main part of the power analysis of the proposed topologies is done on multi-phase versions (specifically six-phase). Mentioned topologies are modelled through the use of the simulation environment PLECS, while the focus is given on the accurate determination of semiconductor devices' power losses. Collected data of each analyzed topology are then processed using the MATLAB environment. The analysis of power parameters aims to find out which of the mentioned topologies achieves the highest efficiency as an VSI system at various power levels using the same input parameters.

The impact of polyphosphoric acid (PPA) polymers and crumb rubber (CR) on bitumen's properties to enhance its performance was examined in this study. Laboratory samples were created with varying percentages of PPA (0.5 % to 2 %) and CR (6 % to 18 %) and subjected to extensive testing. Findings indicated that the combination of PPA and CR led to notable improvements in bitumen performance, including increased viscosity, softening point, elasticity, and recovery rates at elevated temperatures. Specifically, samples with 18 % CR and 1.0 % or 2.0 % PPA demonstrated exceptional rheological properties and strength. The optimal combination (18% CR and 1.0% PPA) resulted in a uniform structure, while the maximum CR content did not compromise bitumen integrity. Both additives effectively minimized temperature sensitivity and aging, enhancing the bitumen's performance class significantly.

This article presents the enhancement and refinement of a simulation model for an integrated universal switched voltage regulator compatible with PSPICE software. The model enables users to create representations of any specific type of switched voltage regulator currently available on the market. The described regulator model is practically applied in widely used configurations of buck converters, including applications in transportation. The accuracy of the regulator model is verified by comparing the simulated waveforms of the converter to those provided in its datasheet. Additionally, the model is employed for the design and simulation analysis of buck converter circuits, with extended current and voltage ranges for their output parameters. In the context of improving the performance of such converters, particular attention is given to enhancing their electromagnetic compatibility.

The lifespan prediction of the bus body of the load-bearing structure has been made and compared to the results of real operation. The maximum approximation of the simulation modelling results in Matlab Simulink to real operation is explained by taking into account a sufficient number of factors influencing durability. This research has the particularity that it allows determining the durability of the bus body even at the design stage, which was not possible with accelerated tests or during the operation of the bus on real routes. The obtained results can be used by bus manufacturers at the design stage, allowing them to change the construction and technology of anticorrosion protection, thereby influencing the durability. In addition, operating organizations will be interested in the obtained results when using the developed methodology in various operating conditions.

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.

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.

Traffic safety assessment is an essential part of traffic planning and engineering. At uncontrolled intersections, the severity of crashes has increased manifolds. This is due to the fact of not following the priority rule during the right-turning movements. In conventional methods, past accident records were used to analyze traffic safety. However, the drawbacks of the traditional method to estimate the severity require a lot of accident data for analysis to draw any conclusion and suggest safety measures. The accuracy of the record of accidents and details is highly uncertain. Therefore, surrogate safety measures are being used to analyze the safety. In the present paper, the gap acceptance time (GT) is used to examine the risk and the speed and gap values define the level of risk and severity (LORS). Moreover, using the value of the critical gap, the probability of risk is estimated. Further, the level of risk and severity is computed based on the gap and speed data of vehicles at an uncontrolled intersection. Hence, with the speed and gap data, the level of risk and severity is classified as low risk, high risk and low severe, and high severe. The methodology implemented is validated by using the actual accident data.

This paper provides an analysis of the values of safety distance between the two moving vehicles, based on the parameters of the behaviour of young drivers. The main objective of this research was to determine the driver's response time for braking manoeuvre (BRT) in car-following situations. The test results were used to verify certain recommendations for the vehicle driving parameters, the principles of driver's performance to increase road traffic safety, etc. The driver's response times, determined during the testing in the simulator, were used to assess the recommended values of the safe following distance under different road conditions and various ways of driver behaviour. In the paper, for different values of BRT a safety distance in emergency traffic situations was determined.

Hydraulic motion platforms are widely utilized in various environments due to their capacity to bear heavy loads and provide long actuator strokes. The predominant control system employed for hydraulic motion platforms is the electro-hydraulic servo system (EHSS) due to its high accuracy and robustness. However, compared to other types of hydraulic valves, the electro-hydraulic servo valve (EHSV) is less durable. An alternative system to EHSS is the electro-hydraulic proportional system (EHPS), which employs an electro-hydraulic proportional valve (EHPV) instead of the EHSV. The EHPV resolves the durability issue at the expense of accuracy and system error. The optimization of durability and accuracy is the core of this study. The tracking behavior and response of both Three degrees of freedom (3 DOF) motion platforms using EHSS and EHPS are investigated across different frequency ranges.

At the underground mines of Kazakhmys Corporation, where different types of highly productive self-propelled equipment with different types of pneumatic wheel drive are operated, there are significant downtime of technological equipment. As practice has shown, application of repair system with use of old methods and means, at operation of underground self-propelled equipment appeared to be ineffective. One of the main reasons of low efficiency of self-propelled machines operation is the absence of the system of continuous monitoring of technical condition of each machine and its aggregates with application of methods and means of diagnostics. To avoid failure, it is necessary to establish the predicted and residual resource at a certain operating time of the machine according to the diagnostics data. This paper outlines the results of research on predicting the residual life of machine units used in the conditions of the mine corporation "Kazakhmys".

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 the limited scope of data, we were only able to verify the validity of Gibrat's law. The data used do not allow to examine the factors influencing the faster growth of small companies compared to large companies. It will be the subject of further research.

The analysis of the statistical values of wear of brake pads in operation, based on which a wear model was developed, is presented in this paper. This model can be used for predicting the remaining service life of brake pads according to the wagon mileage.
The distribution function of wear on the upper and lower parts of the pad was determined, which made it possible to find the main qualitative characteristics, namely, the wear intensity, the γ-percentage wear, and the average pad wear at a specified wagon mileage.
The results of the study can be factored for solving complex engineering problems of excessive wear of composite brake pads used for freight rolling stock; they could also help to extend the guaranteed overhaul period and improve the railway traffic safety.

The article is devoted to the study of dynamic interaction of rail track and freight wagons under increased axial load. In conditions of increasing the freight traffic volumes and axial loads, the importance of accurate understanding of the mechanisms affecting the wear of rail track elements becomes especially important. In this paper the authors have carried out experimental research and comparative analysis of freight wagon trolleys of different models. As a result of dynamic tests of the freight wagon trolleys, the necessary parameters of dynamic qualities of different models of wagons and their optimal values of axial loads of freight wagons are obtained. The necessity of improving the current design of wagon trolleys and reinforcing the design of railway track with the use of R65 type rails and reinforced concrete sleepers is substantiated. According to the data of trolley design comparison of different models, the bending moment and maximum load indices are established.

Every year a large number of vehicles travel on Poland's roads. The technical condition of vehicles largely depends on the technical condition of the road infrastructure. For this reason, the purpose of the article was to analyze the technical condition of the road infrastructure. The analysis was carried out with the help of a questionnaire survey on a random group of 380 people living and using roads in the Wielkopolska province.

The quadcopter persist as important roles across diverse applications, and the enhancement of their control efficacy has been the subject of extensive research.
In this work, the authors proposed optimal Proportional Integral (PI) controller based Fuzzy Logic Control (FLC) for the roll, pitch, altitude, and yaw motions of the quadcopter system. The proposed technique uses the Particle Swarm Optimization (PSO) algorithm to tune the parameters of the FLC and enhance the quadcopter performance. The simulation results show that the proposed technique achieves smoothness of control and significant improvement over classical techniques, as the rise time and the settling time are reduced by 61 % and 66 %, respectively. These times are important for stabilizing the system’s response speed and avoiding overshooting or oscillating. This indicates that the FLCPI-PSO can achieve the desired roll and altitude angles more rapidly and effectively.

The article highlights is determination of the main strength indicators of the modernized brake lever transmission for a wagon bogie. The special feature of this modernization is that the technological pin-hole in the strut is displaced by 112 ± 2 mm towards the bolster beam, i.e., in line with the pendulum joints. This helps to eliminate abnormal wear of the brake pads in operation. To substantiate the proposed modernization, the strength of the brake lever transmission was calculated. It was found that the maximum equivalent stresses were 124 MPa; they occurred in the tension member. The resulting stresses did not exceed the permissible values. Thus, the proposed modernization measures are appropriate.
This research could improve the safety of rail freight operations and profitability of the rail transport.

The article discusses the types of urban electric transport used in Belarusian cities, gives a detailed classification and comparison of available vehicles. Various options for increasing the share of environmentally friendly transport through the use of electric buses and trolleybuses are considered, an assessment and a comparative analysis of the options are given. Features of the drivers' work planning and drawing up of the schedule taking into account safety requirements are considered.
A methodology for assessing the efficiency of urban passenger transport has been developed, taking into account the development of electric vehicles.

The work highlights the results of a study into the dual wedge-shaped wear of composite brake pads for freight wagons. It has been found that the over-normative wear makes the area of a composite brake pad larger in the lower part up to a value directly proportional to the wagon mileage and smaller in the upper part. To assess the braking efficiency of a rail vehicle, a graphical analytical method has been developed; it allows determining the factor of dual wedge-shaped wear of pads depending on the wagon mileage. The results of calculation were verified by comparing two samplings obtained by mathematical and computer modelling. The results of calculation have proven that the hypothesis on the adequacy is not rejected.
The results of the study conducted will allow more accurate assessment of the braking efficiency of freight rolling stock to be made, as well as contribute to improving the safety of train traffic.

In the paper, some selected results concerning the ellipses of adhesion for various conditions of motion of a vehicle model, have been presented. The analysis, regarding the phenomena between the road and the wheels of the given motor vehicle's model, was previously carried out in the earlier paper by the author. However, they proved useful for the second part of research based on determination of the ellipses of adhesion. This can enable answering the question whether the road conditions may affect the maximum longitudinal and lateral forces combining such ellipses in the contact plane between the road and the wheels. The analysis has been presented based on the previously obtained results.