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The behaviour of lightweight concrete (LWC) edge column-slab connections reinforced with two types of flexural reinforcement glass fiber-reinforced polymer (GFRP) and steel bars with different ratios of shear reinforcement are investigated experimentally and analytically using ABAQUS software. The experimental protocol covered evaluation of eight slabs and edge columns measuring subjected to static loading. Slabs are evaluated as supported, free-standing at one edge, and the column connection is included. The slabs are divided into two groupings, with four slabs in each group. The first group was reinforced with steel flexural, while the second group was reinforced with GFRP reinforcement. Within each group, one slab lacked shear reinforcement, while the other was reinforced with a varying shear reinforcement ratio. A good agreement was found between the numerical FE model and experimental outcomes in most tested slabs.

The study analysed the driving performance and visual impairment of 92 participants under six different distraction scenarios. Using a car simulator and by simulating two real-world roads, a variety of data was collected, including driver behavior and vehicle-related data. According to a statistical analysis conducted during and before the distraction on road 1, females significantly increased speed more than males when using a hand-held call (=scenario #3), hands-free call (=scenario #4), text (=scenario #6), and voice command text (=scenario #7). The Kruskal-Wallis H test was performed on gender, age, vehicle speed, throttle, and offset from the center of the road subcategories, while selecting the more correlated variable with each type of distraction. Finally, the generalized linear regression model was used to provide a significant relationship between the frequency of distraction and highly correlated independent variables.

The results of research, devoted to operation of an electric pulse muffler designed for cleaning exhaust gases of an internal combustion engine, are presented in this article. The problem considered in this research is establishing the optimal operating mode of the electric pulse muffler by changing the parameters of the distance between the electrodes and the frequency of the electric pulse. To solve this problem, experimental research on laboratory and experimental stands was carried out, which confirmed effective reduction of the gas smoke indices at adjustment of the specified parameters. As a result, a methodology was developed to calculate the optimal values of the distance and frequency parameters, at which the operation of the electric pulse muffler will be considered productive and the degree of gas purification will be effective. The optimum value of the distance between electrodes is 0.78-6 ∙10-3 m with an electric pulse frequency in the range of 127-128∙10³Hz.

Cylinder liners of an automotive internal combustion engine are subject to significant losses during operation. Severe operating conditions of cylinder liners lead to the appearance of various defects that must be eliminated to ensure the performance of the internal combustion engine. Currently, several methods have been developed for restoring and strengthening the inner surface of cylinder liners of automobile and tractor engines. Analyzing the considered methods for strengthening and restoring cylinder liners, their advantages and disadvantages from the point of view of increasing their durability, it can be assumed that the high-quality restoration of cylinder liners will be provided by a method of applying a coating by centrifugal induction sintering of powder material. Self-fluxing powders were used as baked powder material.

The paper presents the results of gyrocopter fuselage experiment testing in a wind tunnel. The model subjected to testing was made in 1:8 scale by 3D printing. The tests included the measurement of forces and aerodynamic moments acting on the model, for a variable fuselage sideslip angle (-20º to 20º), and for three different positions of the rudder setting (0º, +5º, +10º). The measurement was carried out at an airspeed of 25 to 26 m/s. Based on the measured values, aerodynamic drag coefficients, lift coefficient and aerodynamic moment coefficients with respect to all axes of the reference system, were determined. The measurements carried out have facilitated the derivation of diverse characteristics, validating our conclusions. The results and conclusions drawn from these experiments can be valuable in enhancing the design and functionality of rotorcraft rudders.

The research presented aimed to compare the transportation performance, as measured by vehicle kilometers, to the operating costs incurred by thirteen transport companies in the Czech Republic from 2010 to 2019. This period was chosen to ensure that our research is not affected by the Covid-19 pandemic. The financial coverage of operating costs includes revenues from fares and compensations from city budgets. We utilized data from the annual reports of The Association of Transport Companies of the Czech Republic. Based on the obtained data, we confirmed a positive relationship between the city's population, the extent of transportation performance, and consequently, the total operating costs.

Recommendations are given on combinations of parameters of box-shaped and "dump" types of dumps for the SHANTUI SD 32 bulldozer, which provide the highest technical characteristics of the bulldozer when moving low-density materials. The optimal dimensions of a box blade for equipping the SHANTUI SD32 bulldozer are a grasp width of up to 3730 mm, radius of curvature of up to 1700 mm, width of the cutting edge of up to 460 mm, canopy width of up to 140 mm, flap length of up to 860 mm. The optimal dimensions of a "landfill" blade for equipping the SHANTUI SD32 bulldozer are a grasp width of up to 3900 mm, radius of curvature of up to 460 mm, width of the cutting edge of up to 124 mm, canopy width of up to 610 mm.

The research aims to develop an algorithm for modelling the process of cutting an infinite volume of soil with a flat cutter in the Abaqus software package. The hypothesis of the existence of energy and volume of resistance to cutting is proposed. The analysis of shock wave distribution in the soil volume is performed. Boundary conditions for the soil volume model are determined, as well as for a flat cutter with linear motion. Stress gradients in the soil during its deformation are determined. Confirmation of the hypothesis about the existence of energy and volume of resistance to cutting was obtained. A logarithmic regression equation was derived based on the obtained volume values.

The performances of different driving circuits configurations designed for silicon carbide MOSFET transistors are compared in this research. The simulation of the double-pulse test (DPT) was performed with the use of three driving circuit configurations. The SiC MOSFET NTH4L022N120M3S has great dynamic parameters, which made it suitable for the DPT simulation. It was performed with six different driving voltage ranges, all within the range between -10 V and 20 V. The results were taken across the wide range of driving resistances placed between the driver and the SiC MOSFET, where the switching losses were taken. Drawing from the observed measurements and derived plots, the optimal UGS driving interval for managing the SiC MOSFET transistor is determined to be -10 V/20 V when using a circuit design that incorporates both turn-on and turn-off resistors and diodes.

The effects of micro-sized montmorillonite clay (MMT) on Portland cement concrete were examined in this study, focusing on regular and calcined MMT as partial cement replacements. Key properties assessed include consistency, setting time, flexural strength, and compressive strength at 7 and 28 days. Regular MMT initially acts as an inert filler, potentially reducing compressive strength, while calcined MMT improves compatibility and strength. Both types extend the setting time, with regular MMT causing more delay. The study highlights that the regular MMT increases water demand and setting time, whereas calcined MMT enhances strength and mitigates these issues. The results emphasize the importance of carefully choosing MMT type and dosage.

The article presents theoretical and experimental results on ultrasonic cleaning of a vehicle radiator. Criterion relationships between ultrasound energy, kinetic energy of the liquid, and shock wave energy were established, enabling the evaluation of cavitation energy efficiency and cleaning effectiveness. Experimental confirmation was obtained using a developed full-size bench. Using the developed full-size bench, the numerical values of parameters were obtained that made it possible to calculate the values of energies involved in the cavitation process, the ratio of which allows evaluating the effectiveness of washing the radiator from scale. The cavitation coefficient of erosion efficiency was established, proving the effectiveness of ultrasonic cleaning. Results confirm the applicability of this method for cleaning the vehicle radiators.

In this paper is considered a promising design of the braking disk mechanism of a construction crane. The analysis of the kinematics of the brake pad drive has shown that due to redundant links in the brake pad drive mechanism the latter are not able to self-align. This leads to uneven braking torque during the smooth braking, overloads and deterioration of the positioning accuracy of the load suspended on the cable. Based on the methods of analyzing the kinematics of complex mechanisms, two variants of modernization without redundant links are proposed. Both variants can be realized without changing the kinematics of the mechanism, but they differ in the complexity of the joint manufacturing technology and depend on the design and dimensional limitations of the brake.

The present article portrays the bibliometric analysis of research conducted on E-mobility worldwide. The study aimed to understand research characteristics, evolution, challenges and potential research trends. Research articles published on E-mobility have been compiled from the Scopus database, resulting in 1737 articles published between 2001 and 2021. The software R Studio has been used for subsequent bibliometric analysis. The analysis examines the research trend in the field of E-mobility. In addition, it identifies the most productive contributors in terms of author, country and sources. Thematic analysis has been performed, as well, to reveal E-mobility research trends, including the most influential articles and authors. The study concludes that very few studies have been conducted on E-mobility and that there is much potential in E-mobility. The present paper can help the researcher pave the research path in E-mobility.

Rapid industrialization and increased diesel engine usage have driven up diesel consumption, burdening economies with heavy petroleum product imports. Diesel fuel emissions, including carbon dioxide, carbon monoxide, and smoke, pose environmental concerns. Biodiesel produced from non-edible vegetable oils offers a sustainable solution.

The purpose of the article was to present the results of braking equipment testing and determination of the adequacy of compressed air production of the braking system when the train is loaded. Experimental tests of the braking system of TE33A diesel locomotive in a goods train are performed. According to the initial data the main parameters of the braking system in the empty and loaded train were evaluated. As a result of tests, and according to the calculated data, the dependences of the volume of the main reservoirs, and the dependences of the required compressor capacity, on the number of axles have been obtained. It has been established that the braking system operation in release modes for a 400-axle train corresponds to the operating conditions and the main requirements of the normative documents.

In this paper is presented a mathematical model of a five-phase induction motor with a cage rotor and a stator coils connected to a star. In constructing the mathematical model, It is assumed that the motor is fed from a five-phase frequency converter with an ideal harmonic waveform of the output supply voltage. It is considered that the motor operates in an open control loop with the ability to control the frequency and amplitude of the supply voltage. The basic voltage equations in a two-phase coordinate system coupled to a stator are derived, as well as the relation for the electromagnetic moment. Based on the parameters measured on a real motor, a dynamic model was implemented in Matlab-Simulink environment. Using the dynamic model, various motor operating states were simulated, such as frequency ramp-up, speed reversal, or operation at super-nominal frequencies.

In solving the problem of energy and resource conservation in transport, polymer composites are of paramount importance. Polymer composite using makes it possible to significantly improve the mechanical properties of the materials and simultaneously to increase the durability of the parts of transport machines. The authors of this article focus on the substantiation of introducing the modifier 4.4'-methylenebis(2-methoxyaniline) with low concentrations into the epoxy resin. Such materials are characterized by increased mechanical strength and the ability to withstand static, dynamic stresses, as well as impact loads, since the values of the properties are: bending stresses at bending - σ = 51.2 to 54.4 MPa, modulus of elasticity at bending - E = 3.0 to 3.2 GPa, impact toughness is W = 8.8 to 9.0 kJ/m². The obtained results of experimental studies of the composite materials properties are in good agreement with the results of testing samples by optical microscopy, which indicates their reliability.

This study explores the significant role of three-wheelers (3W) on urban road traffic, focusing on the reduction in average vehicle speeds and its consequential impact on the Level of Service (LOS) of the road. Data collected from various traffic volumes reveal significant speed reductions ranging from 4 % to 35 % due to the movement of 3Ws on the road. To model this phenomenon, Artificial Neural Network (ANN) is employed. The resulting reductions in speed, induced by the 3W, trigger LOS degradation, leading to congestion and delays. A noteworthy finding is that the traffic flow naturally gravitates towards the LOS C, underscoring the substantial role played by the 3W in diminishing the overall LOS of the road. This research offers critical insights into the dynamics of urban traffic influenced by the 3W, providing a valuable foundation for traffic management and urban planning efforts.

The long-term relationships between the N95 ("Natural 95") gasoline prices and economic factors, such as Brent crude oil prices, diesel fuel prices, and the CZK/USD exchange rate from 2014 to 2024, was investigated within this research. The Engle-Granger cointegration test was used to identify any stable long-term connections between these variables. Despite the comprehensive tests, facilitated by the Matlab software, no evidence of cointegration was consistently found, indicating that these economic factors do not significantly influence N95 gasoline prices over the long term. The findings suggest that, while the short-term fluctuations in these economic indicators may temporarily impact gasoline prices, they are not reliable predictors of the long-term trends.

The article deals with the methodology of selecting the optimal decision for the maintenance and operation of freight cars. The statistics of failures for the main units of freight cars has been collected. A hypothesis has been proposed about the method of selecting a decision based on the optimality criterion, i.e. the maximum profit. The optimality criterion is the difference between the income and the costs and is the function of the frequency of certain operations on each of the car units. An algorithm has been developed that allows for the effective optimization of the processes of operating, repairing, and writing-off the cars, ensuring an increase in the competitiveness of rail transport due to the rational use of resources and optimization (reduction) of costs.

Human capital as a part of intellectual capital has crucial impact on the overall development of all sectors of national economy. This trend can also be confirmed by the growing number of academic papers dealing with the issue. This paper presents results of a questionnaire survey that investigated the human capital in terms of selected motivational factors and employability prospects as seen by students of high schools programs related to transport and communications. The main objective was to get an insight into the current situation in the sector and its attractiveness as seen by potential future employees. The questionnaire survey was carried out in April 2016 and its respondents were future high school graduates, who can either continue to study transport and communications at university or enter the job market and search for a job in the sector straight away. Results obtained from a series of statistical tests using the Two-way ANOVA method can serve both companies and educational institutions as a basis for implementation of measures that would guarantee sustainable development of human resources in this field.

Decision-making is an integral part of every human's life, both personal and professional, and today's highly globalized world brings many different factors that affect the decision-making process. General economic theory of utility is grounded in the assumption that people make decisions rationally. Recently, however, its limits have been challenged by both scientific and professional public - the theory of rational choice acknowledges only a limited number of factors that influence the decision-making. The aim of the present article is to discover whether the current debate can be applicable to decision-making processes of flight passengers in a case study of travelers on route from Prague to London. The article presents results of a primary research carried out by authors in 2018. The survey set to explore validity of choice theory in the sector of logistics, in particular in decision-making processes of passengers who buy flight ticket on route Prague - London. At the base of result it can be confirmed that the classical theory of rational choice in economical perspective has been proven false. When people's behavior, as a result of their decision making, serves as a basis for future predictions of development in a given area, it is essential to take into account other, usually hidden factors, which also affect the decision-making process.

The freight transport performance is growing. The transport sector is also one of the largest producers of emissions. This must be reflected not only by production companies but also by other stakeholders. The issue of transport emissions is particularly important for city residents, so today the concept of sustainable city logistics is emphasized. Companies should deal with the amount of produced emissions. The use of emission calculators would support operational, tactical and strategic business decision-making. The aim of this article is to analyse the approaches used in available free calculators of emission arising from the freight transport. The focus was on the transport modes that calculators include, input data, output data and methodologies used to calculate emissions. The method of systematic review was used to search analysed freight transport emissions calculators. The method of content analysis was used to analyse inputs, outputs and freight transport emissions calculator's methodologies. The method of qualitative comparative analysis was used to analyse and compare the freight transport emissions calculators.

Transport infrastructure is not currently the domain of activity of solely the public sector. Governments entrust the provision of services or realization of investment tasks to private entities and the form of involvement of private investors may be the public-private partnership PPP. Successful implementation of the PPP projects requires appropriate economic, legal, institutional and social conditions.
The article identifies these determinants based on the literature on the subject and then their analysis in relation to conditions of operation and market development of the PPP projects in the area of transport infrastructure in Poland. The analysis covered the years 2009-2018 and was conducted against the background of development of the PPP market in selected EU countries.

The established mode of operation of the conveyor with a nominal linear load is the most economically advantageous from the point of view of increasing the energy efficiency of mineral transportation, in which the cargo flow with minerals corresponds to the nominal productivity of the conveyor. An increase in the linear load of the working branch of the traction-bearing body to a nominal value reduces the share of unproductive consumption due to which energy savings are achieved for a certain period of time, characterized by its hourly average value.

The purpose is to determine the impact of operating conditions on the reliability of vehicles, to identify the main causes of failure of truck units and assemblies and to find ways to improve their reliability. The main methods are a systematic approach to analysis of complex technological systems, the fault tree analysis to identify the most common causes of failure of trucks in the climatic conditions of Central Asia. It has been revealed that one of the frequent causes of failure of units and assemblies is fatigue failure, the finite element modelling of which allowed the study to obtain a diagram of limit deviations for various cycle asymmetries and as a result, the ability to predict the process of fatigue failure under the influence of external factors. The study results are aimed at the possibility of predicting the failure of components and assemblies of trucks conditioned by fatigue failure.

The article describes the design and optimization of operation of an electric bus  powered  by  the  hydrogen  fuel  cells.  At  the  beginning,  an  approach  to  design  of  a  12-meter  urban  bus,  powered  by  hydrogen,  is  presented,  as  well  as  examples  of  components  for  its  construction.  Next,  the  problem  of  selecting  the  size  of  traction  batteries  and  stacks  of  the  Proton  Exchange  Membrane  (PEM)  hydrogen  fuel  cells  was  discussed.  These  are  the  key  components  affecting  the  price  of  the  bus  and  should  be  subject  to  optimization. The results of optimization of the size of traction batteries and the  fuel  cell  system  for  a  bus  traveling  in  inter-city  traffic  are  presented.  The optimization was based on data from the literature and data from the monitoring system of actual hydrogen powered buses located on the Internet platform.  The  main  purpose  of  the  research,  which  was  to  determine  the  total costs of ownership (TCO), is presented as well.

Container ships represent the fastest growing segment of maritime transport. The need to reduce unit transportation costs and environmental impact has led to development of the most capacious ultra-large container ships operating on the world's major shipping routes. A representative database of ultra-large container ships was created and further subdivided according to the main technical parameters. Using a simple cubic regression model, based on the least squares method, an equation, compliant to the general propeller law, was developed to predict the propulsion power of ultra-large container ships as a function of their sailing speed. The results obtained using the developed equation should be sufficiently close to the results of the exact verification calculations at the technical design stage. Then this prediction would find application in the design of both main propulsion, as well as waste heat and cold recovery systems.

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 quite intuitive for both, as well. However, Aimsun's graphical interface interprets results more user-friendly, because Sumo is an open-access software presented as an effective alternative tool for transport modeling.

With an increasing number of vehicles, there is a need for reliable and secure communication between subjects participating in the dynamic traffic environment. This kind of communication is called V2X (Vehicle-to-Everything). It can also contribute to higher level of autonomous driving. The V2X model operation is enabled by use of the newest technologies and standards, defined by 3GPP Organization. In this paper, a review of the V2X communication models, available technologies and standards are studied.