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The problem of wheel and rail wear in railway transport generates costs of reprofiling and availability of vehicles and infrastructure. One of the possibilities of wear minimizing is decreasing of the friction coefficient in wheel-rail contact by means of lubricants. Such a solution has drawbacks from which the most crucial are: decrease of tractive/braking forces and difficulties with the precise spreading of the lubricant. These disadvantages may be avoided by modern, innovative self-lubricating coatings, applied at the production stage on the wheel flanges. The aim of the study is to investigate the effect of self-lubricating coatings on a rail vehicle's dynamic behaviour, safety against derailment and predicted wheel wear. The numerical study was performed using the wagon multibody model with simulated self-lubricating coating on wheel flanges.

This paper presents a method for the vehicle speed estimation with a Fuzzy Logic based algorithm. The algorithm acquires the measurements of the yaw rate, steering angle, wheel velocities and exploits a set of five Fuzzy Logics dedicated to different driving conditions. The technique estimates the speed exploiting a weighted average of the contributions provided by the longitudinal acceleration and the credibility assigned by the Fuzzy Logics to the measurements of the wheels' speed. The method is experimentally evaluated on an all-wheel drive electric racing vehicle and is valid for the front and rear wheel drive configurations. The experimental validation is performed by comparing the obtained estimation with the result of computing the speed as the average of the linear velocity of the four wheels. A comparison to the integral of the vehicle acceleration over time is reported.

The transport process is characterized by transport operations and the relationships between them, the route, the time of transport and the type of product transported. One of these parameters is the degree of risk associated with a possible disruption of the transport process. Therefore, this article aims to present the possibility of calculating the degree of risk on the selected transport route. The risk level is calculated on based on the actual risk incidents on the transport route.

The article presents materials on use of ultrasonic waves to reduce the smoke and toxicity of diesel engine exhaust gases. The results of the experiments are presented. The hypothesis on the reduction of smoke and toxicity of the exhaust gas due to the acceleration of the coagulation of its particles under the action of ultrasound has been confirmed.

This paper deals with importance of executing maintenance activities of rolling stocks by the example of the electric multiple unit EN96 series and with influence of repairing rolling stocks on the transport safety. It also discusses Poland's Supreme Audit Office report for the 2017 year that concerns the condition of safety of the rail transport in Poland. It describes the way in which the maintenance operations are performed with a division of the maintenance levels that depend of time of utilization and distance travelled by a vehicle.

The mathematical modelling is an inseparable part of mechanical engineers' activities. It is applied in design, optimization, verifying, as well as modifying of products. The approach of creating virtual models and their analyzing without having real products is applied in several domains. A mathematical model is given by equations of motion. The main objective of this work is to present the way how a mathematical model of a car powertrain operation is derived and applied in practical applications. A semi-trailer tractor with a standard powertrain was chosen as a reference car. The derived equations of motion are written in a matrix form and subsequently they are solved by means of a technical programming language Matlab. Parameters of the solved tractor mechanical system come from the real data and they are supplemented by the empirical data.

This study aims to explore the constraints of the Travel Costs Budget Frontier (TCBF) before a full-charged fare is implemented for the bus system known as the "Trans Koetaradja" in the city of Banda Aceh, Indonesia. A stochastic frontier analysis was used to identify how people allocate their share of income for transportation in line with their mobility and socio-demographic characteristics. The findings showed the TCBF to be influenced by commuting trip activities, private mode usage, owning car and motorcycle and income limits. Barriers were observed to be restricting the low-medium income groups. Owning their own private modes within the low-medium income groups does mean household disbursement and could impose their transport expenditure rather than public modes usage. There is a need to devise policies considering the low-medium incomes to implement impartial full-charge to ensure affordable bus fare.

The time when the only job of a manager was to delegate work to employees is over. At the present time, an ability to motivate employees is considered an essential skill for managers. It is complex and systematic effort of a manager to create a working environment and atmosphere supporting the inner needs and interests of employees affecting their behaviour and stimulating the performance positively. Differences in the level of workers' motivation in repair and maintenance service enterprise in the rail transport was defined using the sample set of almost 1,000 respondents and ANOVA and Duncan test. Following the results, it can be stated that the structure of motivation factors, as well as their importance, changed significantly in repair and maintenance service enterprise in the rail transport over the observation period.

It has been determined that the greatest risk of an error in determining the technical condition of the axle box unit in the so-called "zone of uncertainty" is in the impossibility of unambiguously assessing its technical condition. To solve this problem, a model is proposed in the form of an n-dimensional radius vector, which has a direction towards an increase in the probability of failure and a deterioration in its parameters' values. Such a model for determining the axle box unit's pre-failure condition will reduce the risk of errors in decision-making.

The study concerns the problem of overloading the vehicles driven on public roads. The gross vehicle mass and individual axle loads are limited by legal regulations. However, a tricking method, applicable to most popular designs of motor vehicles and multiaxial tractor-semitrailer units, has been shown that the weighing inspectors, even if provided with precise scales, may be deceived without any interference in the scale operation. In such a method, the current vehicle state may be changed by modifying the stiffness of individual pneumatic suspension springs, which is now technically feasible. The author used two authorial vehicle models and a simulation program. Calculation results obtained for a four-axle motor vehicle and a five-axle tractor-semitrailer unit, taken as an example, have been demonstrated. They show that a deceit is possible when a vehicle is weighed in motion with a very low speed.

Accuracy, integrity, continuity and availability are the basic quality parameters extremely important in satellite navigation. The article presents results of research using the European Geostationary Navigation Overlay Service (EGNOS) that belongs to the group of Satellite Based Augmentation Systems (SBAS). The measurement data adopted for analysis were recorded in years: 2012, 2014, 2015, 2017 and 2018 in the north-eastern Poland. Results of the analysis showed a significant reduction in the maximum GPS / EGNOS positioning error values from 2014 onwards (compared to results from 2012). In general, values of parameters characterizing accuracy, integrity and availability meet the requirements for EGNOS applications in APV-1 and LPV-200 aviation procedures. It the case of continuity the requirements are not met.

The presented work discusses a methodology for analysis of noise emissions from a diesel engine. A numerical model of the piston motion, analyzing its lateral, reciprocating and rotation motion, has been presented in order to investigate the lateral motion of the piston skirt assembly and resulting vibrations induced as a result of these motions in the engine block. Various parameters of modal analysis were obtained using the mobility analysis. The presented methodology was validated by data obtained from a diesel engine test set up. The predicted results matched well with those of measured data, hence validating the presented scheme.

A scientific approach to calculating the parameters and characteristics of an asynchronous motor in the inter-turn short circuit mode in one phase of the stator is proposed to create the foundations of a diagnostic complex for assessing the condition of asynchronous motors of the transport infrastructure. This approach consists of the fact that in the model with which the research is carried out, it is proposed to take into account changes in the mutual inductance of the motor when the AC impedance of one of the stator phases changes. Using a new approach to modeling processes occurring in an asynchronous motor during the inter-turn short circuit in one phase of the stator, pulsations of the torque on the motor shaft were studied for different values of the AC impedance and resistance of one of the stator winding phases, which corresponds to varying degrees of the inter-turn short circuits.

The evaluation of the bearing capacity of asphalt pavements is usually performed by analysing the deflections measured by a Falling Weight Deflectometer (FWD). The deflection changes with the pavement temperature. In evaluation is necessary to consider the thermal gradient of pavement and perform the temperature correction. The article contains an analysis of effects of the pavement temperature on FWD results on the long-term monitored sections. The temperature correction was performed on measured deflections or back-calculated elasticity moduli. The moduli recalculated to the temperature of 20 °C according to both procedures were similar. Comparison of moduli determined by recalculation to moduli back-calculated from the deflection bowls measured at the temperature of 20 °C, has proven smaller differences for the moduli determined from the deflection bowl corrected to the temperature of 20 °C.

This paper presents a method for the vehicle speed estimation with a Fuzzy Logic based algorithm. The algorithm acquires the measurements of the yaw rate, steering angle, wheel velocities and exploits a set of five Fuzzy Logics dedicated to different driving conditions. The technique estimates the speed exploiting a weighted average of the contributions provided by the longitudinal acceleration and the credibility assigned by the Fuzzy Logics to the measurements of the wheels' speed. The method is experimentally evaluated on an all-wheel drive electric racing vehicle and is valid for the front and rear wheel drive configurations. The experimental validation is performed by comparing the obtained estimation with the result of computing the speed as the average of the linear velocity of the four wheels. A comparison to the integral of the vehicle acceleration over time is reported.

Traffic in Mexico City poses a serious problem of vehicle saturation that causes a decrease in speed and increased transport time in the streets that suffer mobility collapses. A macroscopic model of vehicular traffic is used to show the effect of viscosity on the vehicular variables (speed and vehicle density), applied to two avenues in Mexico City, is studied. The input parameters were calculated following the Greenberg model. As the original model presents numerical divergences, the two assumptions corresponding to conservation of the vehicle's mass and the viscous term are modified. The results suggest that the viscosity depends on time and that it can be adapted to recommend modifications in urban mobility parameters, or even to implement the public planning policies in construction of infrastructure for urban transport, to make vehicle flow more efficient.

The paper presents a methodology to evaluate a rescue and training phantom for road rescuing organized by Police officers. The methodology is exemplified by the Crash Kelly phantom, static and dynamic functionalities of which seem to be more frequently implemented in the road safety training processes. It stems from a morphological analysis, focusing on the quality of rescue activities, emergency resources' adequacy and the training levels. In addition, experts' evaluation allows to examine phantoms using 6 practically determined criteria, expressing their strengths and weaknesses in analysed context.
The results introduce Crash Kelly as a reference training equipment for Police officers dedicated to rescue victims after the road accidents. Basing on the research results, practical training guidelines are formulated.

This paper concentrates on temperature distribution in the gas turbine blade equipped by the cooling holes system on transient heat transfer. The present study requires the specification of internal and external boundary conditions. The calculations had been done using both Crank-Nicolson algorithm, explicit and implicit methods, in which different heat transfer coefficients on internal cooling surfaces of the holes were applied. The value of coefficients has a direct and crucial impact on the final result. The heat transfer coefficient of cooling the working surface of the of heat pipes was 1600 W/(m2K). It was found that there were no significant differences of temperature distribution in comparison of results from explicit method in the Ansys analysis, Crank-Nicolson algorithm and implicit method in Matlab. The simulation is based on Finite Element Method, which uses the Crank Nicolson algorithm.

In the paper authors investigate dynamics of a controlled quadcopter in terms of the possibility of its use for detection, observation, tracking and laser illuminating of both stationary and moving ground targets in the conditions of impact of random and kinematic excitations. The drone is equipped with a scanning and tracking Gyroscopic Head (GH) coupled with a laser target indicator. The drone is affected by random disturbances in the form of wind gusts or explosions of missiles. Kinematic excitations, such as drone maneuvers and vibrations from engines, act on the GH. This paper focuses mainly on control and stabilization of the gyroscopic head placed on the drone during the search, tracking and simultaneous laser illuminating of the target.

The purchase decisions require information on where each phase in aretail supply chain should be placed. The presented method is an integrated tool for retail supply chain totransaction cost optimization. The model does not only present a company-level lean management's decisions within a supply chain, but it also shows the exact method to optimize the supply chain competitiveness. The allocation model also illustrates how the purchase decisions are allocated for producer, distributor and retail companies. The complexity of the allocation model may be affected by the size of the logistic costs, the algorithm used to calculate the supply chain purchase decisions and the final needs of the customers. The lean management approach could be a redemption to a company, but the results do not help to enhance competitiveness for the whole supply chain in every case. In this paper, a model method is demonstrated that helps to gain benefit of the lowest cost of integrated inventory management decisions. One of the essential parts ofthis research is that not onlythe lean management' result is considered, but effects of purchase decisions are integrated into the whole retail supply chain, as well. This type ofintegrated approachcan have an exponential impact on profitability on supply chain level effectiveness. In the paper are discussed issues that are important from the perspective of carriers, truck owners and operators, transportation policy makers and shippers. Different capacities of transportation and their costs and performance characteristics from lean aspect are discussed as well.

The article presents an analysis of the freight forwarder and carrier costs on transport in chosen country of Western Europe. Costs of transport point out to several existing problems in this part of Europe. The case study is given that deals about chosen transport in France. The article contains a review of transport routes during 2019, which were performed by an international forwarding company. These sessions were carried out in problematic areas in France. These are the transport of refrigerated and frozen perishable goods. The shipments are realized between logistics centres in France. The high problem is with carriers, with qualifications of their drivers, the number of drivers and seasonality of the goods. The article describes these problems as dependences of the forwarder´s costs on individual transport routes. The article deals about more solutions, which could be used in this part of Europe.

This article presents the 3D computational modeling method for reinforced concrete structures. An example of calculation of the reinforced concrete beam, using the Finite Element Method in SCAD++ following proposed algorithm, is given. Results comparison to the analytical calculation of the model with selected reinforcement is presented. For concrete, the 3D solid Finite Elements are used and the 3D beam elements for reinforcement. The model is formed using AutoCAD and AutoLISP, which creates a text data file in SCAD format for the description of model. In addition, computation of the 3D model of the crossbar with a crack is performed. Crack sizes are set in the stretched zone based on data from initial calculation. Graphic results obtained in SCAD++ are presented.

The problem of consolidation of goods for the provider of logistic services, which is a third part that delivers goods from many suppliers to one business client in time horizon was analysed in this article. Every parcel has a fixed date of reception in the source and delivery schedule in a destination. In the age of highly developed economy, time pressure and costs, outsourcing is a condition necessary to improve the functioning of enterprises. New logistic chains, networks of terminals and intermodal connections are built every year to reduce the transport costs and improve the whole process. In this article, the authors presented the benefits resulting from consolidation of cargos in the road transport. Special emphasis was put on determination of the role of the transport costs reduction using the cargo consolidation services.

Due to their strong abilities and easy usage, unmanned aerial vehicles (UAVs) commonly named drones have found a place and merged in the different industrial sectors. These varieties of applications encourage researchers to search for new control algorithms that make drones operate smoothly. In this regard, the present study mains to design a PID controller for four motors drones (quadcopter). For this purpose, a state-space representation of the drone is proposed based on Newton Euler's formularies for a rigid body. For better performance of the control algorithm (PID) the parameters Kp, Ki, and Kd for the controller are established using an optimization search schema based on a genetic algorithm. Various simulations were performed to test the proposed idea.

In the paper, the present state of scientific knowledge in authorising the types of railway vehicles in Slovakia and abroad is analysed by the authors. The aim of the authorisation of the types of railway vehicles is to take into account the interests of the whole society in the field of transport in the manufacturing of these vehicles or their import from abroad. These interests mainly include a greater security of transport, as well as a greater quality, reliability and lifespan of railway vehicles. The authors also analyse the Commission Recommendation 2014/897/EU of 5 December 2014 on matters related to the placing in service and use of structural subsystems and vehicles under Directives 2008/57/EC and 2004/49/EC of the European Parliament and of the Council, which should contain instructions related to the matters in question. At the same time, it is necessary to take into account Directive (EU) 2016/797 of the European Parliament and of the Council of 11 May 2016 on the interoperability of the rail system within the European Union, and Directive (EU) 2016/798 of the European Parliament and of the Council of 11 May 2016 on the railway safety. In addition to ensuring the applicability of interoperability regulations (new directives, regulations, decisions, recommendations, etc.), the aim of this paper is to present a methodology of authorising the types of railway vehicles and a software model (SW) of authorising the types of railway vehicles, with European legislation as a possible tool to speed up and simplify the entire process. The paper is concluded by three types of authorisation processes for different railway vehicles and their accessories, comparing the length and complexity of processing using the standard authorisation process and using the SW tool proposed.

Computer simulation seems to be one of the cheapest and relatively fast methods of investigating vehicle motion. Thereby, it may be important in the case of calculations for the reconstruction of traffic incidents. In particular, that may be important to answer the following question: How wheels' normal reaction forces differ during the cornering of a vehicle?
In this article, the authors presented how the normal reaction forces vary in the case of roll motion of a vehicle body. Suitable mathematical equations are presented. Furthermore, the measurements of the height of the centre of gravity were performed, which was necessary to obtain the normal reaction forces while vehicle body rolls. The authors decided to apply dimensionless coefficients, which represented the properties of a front and rear suspension. Additionally, dimensionless parameters were applied to consider the impact of asymmetrical distribution of vehicle load on normal reaction forces of wheels on a road surface.

Projecting of urban transport infrastructure, which forms a comfortable habitat and development of territories, is impossible without forecasting the parameters of transport and passenger flows. These parameters are formed under the influence of the subjective choice of urban residents on the routes along the road and route network. The study aims to identify factors affecting the distribution of transport and passenger flows through the existing urban transport network. It is revealed that the gravity function of employees of city-forming enterprises, which determines the emergence and absorption of transport and passenger flows of the city districts, can be described by parameters of urban structure, socio-economic factors and parameters that characterize zones of residence and main area of employment. The developed model was tested on real data from Kharkov - the second largest city in Ukraine.

Mining machines' components, or the whole structure, are prone to frequent premature damages and fractures what is explained either by inadequate design and construction or by insufficient knowledge of the material's and welded joints' properties and oversights in manufacturing. Here is considered the bucket-wheel excavator, i.e. the fracture of the tooth of the girth gear, which enables the circular motion of the excavator's upper structure (which was in operation for 5000 hours). The gear was made of the cast steel GS 40 MnCrSi3 V. The reparatory hard-facing (HF) technology of the fractured tooth required specification of numerous operations including the preparation works. The reparation realized the two-fold savings, in time and money - the new girth gear costs over 500 000 € and its manufacturing lasts 6 to 9 months, while the safety and quality of the repaired tooth was guaranteed.

Methodology of the heat outcome from the bus compartment in terms of duration factor of cooling and heating capacity is introduced. Value of the air temperature change in the compartment was calculated. The balance method of the spent heat is used to assess the level of keeping a proper temperature environment in the bus saloon when a comfortable microclimate is created for passengers via the proper conditioning system functioning. Models of the heat transmission notions were used for calculation regarding different categories of the heat load creation. A developed numeric algorithm was introduced in the article as well as a program for modelling the transitory heat processes in the compartment of the city bus equipped with an air-conditioner enabling to take into account various constructive decisions in the system of comfortable provision of city buses and model unstable heat processes.

This paper deals with the simulation verification of balancing systems with different numbers of batteries. There is a simulation model of the battery with adjustable inputs and a simulation model of flyback converter. These components are interconnected and controlled externally to ensure balancing of individual cells. The batteries are connected in series and a flyback converter is connected to each battery. The outputs of these inverters are connected to the output of all the batteries. So, one can say that this balancing system is designed to lighten the charger. The results of the simulations show the voltage, current and State of Charge (SoC) of the batteries. Simulation models are presented in diagrams. These models were created in the PLECS environment.