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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.

In India, priority rules at un-signalized intersections are often ignored by drivers. The present paper reports the applicability of deterministic and probabilistic methods for estimating the critical gaps at high-speed un-signalized T-intersections. The critical gap is estimated for different vehicle types and crossing movements. The study quantifies the implication of critical gap values on the capacity and safety values at un-signalized T-intersections. The results point to conclusion that the value obtained for the critical gap using deterministic methods is lower than that estimated by the probabilistic method. The gap values estimated using the Binary Logit Regression method are similar to those computed using the equation reported in Indo-HCM (2017). It was concluded that a lower value of the critical gap yields a higher capacity value and a higher value of risk probability.

Countries seek to use the knowledge and capital of the private sector to minimise the gap between the transport infrastructure needs and the capacity of their budgets. A form of private investor involvement is usually a public-private partnership PPP. However, success in implementing the PPP projects requires appropriate economic, legal and institutional conditions. The article presents results of research aimed at identifying the PPP success factors in Poland and assessing the strength of impact of individual factors on the implementation of projects. An analysis of the subject literature was carried out, based on which the success factors were determined. Next, econometric modelling methods were applied (correlation and regression), which were used to measure the degree of correlation between the variables and showed the relationships of variables to each other.

The aim of the paper is to inform about the possibilities of using a fuzzy logical deduction in security practice. The fuzzy logic deduction allows to record the management experience in IF - THEN rules and does not require a precise description of the parameters of the controlled function. This property is an important asset for risk assessment in an incompletely defined environment. The application of the method is demonstrated in the security risk assessment of the physical protection of the national railway with a focus on the corridor railway lines and with regard to the future construction of high-speed railway lines in the Czech Republic. At present, it is a generally accepted fact that securing basic transport functions is a prerequisite for successful crisis management. These functions can be specified as road and rail negotiability.

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 article presents an assessment of the use of alternative fuels in Europe with an emphasis on electromobility. In this regard, the impact of political intentions, ambitions and goals are analyzed, in relation to the current situation. Based on the results of empirical measurements, the efficiency of implementation of a European publicly accessible infrastructure for charging electric vehicles was determined. Using the method, the efficiency of electromobility in all the countries of the European Union was investigated. The resulting parameters are comparable in the context of the objectives of the Green Deal and the expected impact of electric cars. Using the results of the DEA model, one can point out the efficiency of countries and suggest ways to improve it.

The aim of the study is the numerical analysis of a bolted connection under the conditions of loss of bearing capacity of some fasteners in this connection. The joined plates in the connection were made of the 3D finite elements, while the fasteners were treated as hybrid models consisting of rigid heads and nuts and flexible beams between them. A model of unilateral contact with friction was used between the joined plates. The bolted connection was first preloaded according to three different tensioning sequences and with a normalised force. After all the bolts were tensioned, the selected bolts were removed, simulating bolt damage under connection loading conditions. The connection was tested for external compressive loads up to 210 kN. The effect of the loosening of the connection on the load in the remaining bolts at the stage of the connection operation was investigated.

The submitted paper deals with designing routes of the vehicles, which provide the transport network services. We limit our focus to such tasks, where the priority is the edge service in the transport network and the initial problem is finding an Eulerian path. Regarding to real-life problems, this contribution presents such procedure of solving, which takes into account both the existence of a mixed transport network containing one-way roads and the existence of a wider transport network. In this network, there are only selected edges with possibility of the effective passages. This problem can be solved by the modified Rural Postman Problem assuming the strongly connected network. Linear programming is a suitable tool for designing optimal routes of service vehicles.

The composite alumina-titania coatings have been widely used in industry fields to protect metallic components from wear, corrosion and thereby prolonging their service time. This paper presents an analysis of the microstructure and mechanical properties of Al2O3-TiO2 composite coatings, plasma sprayed on steel substrates from feedstocks containing various concentrations of the TiO2 powder. The coatings revealed lamellar microstructure, formed by the rapid solidification of molten droplets of the powder on previously deposited splats. The main phase identified in the coatings was γ-Al2O3 phase, the others were TiO2 and α-Al2O3, as well as amorphous phase. The results indicated significant improvement of hardness, Young's modulus and fracture resistance of coatings with an increase in TiO2 from 3 wt. % to 13 wt. %. The friction coefficient was found to be the same for both coatings.

Logistics is a very important service, which can influence the international trade. However, the rates in the development of international activities vary by country. In developing countries, the share of the logistics services is increasing, while the share of manufacturing activities, especially those with the lower added value, is declining due to the relocation of production to other countries. In order to achieve competitive advantages in the logistics sector, the development of logistics services with the higher added value is required. The effectiveness of logistics processes is very important for international competitiveness. In the paper, is presented the literature review on logistics performance. After presenting relevant research, the effectiveness of logistics is compared using the logistics performance index based on the Data Envelopment Analysis (DEA). The DEA analysis is a benchmarking technique which is useful for a multi-criteria comparison. Values of the international logistics performance index for 2016, for selected European countries, were used for the input and output variables of the DEA model. European countries rank high in the international comparison of the logistics performance index. In the paper, it was found out that the compared countries are competitive in international business, but not all the countries are considered as efficient. Germany achieves the highest points in the international comparison of the LPI but, does not achieve efficiency. We also found out that Austria, Serbia, Russian Federation and Bosnia and Herzegovina were efficient, while other compared countries did not.

The objective of this study was to assess the effect of selected operational and technical factors on downtime of vehicles. The sample consisted of buses from a municipal transport company (Poland). Estimation of parameters of a linear regression model was performed. Month of failure (downtime event) and its type were used as predictors. Failures were divided into three categories: events related to the company´s operations, including vehicle failures (1) and other (organizational) problems (2), as well as failures caused by external factors unrelated to the operations of the transport company (3). The downtime was found to be significantly associated with failure type and month of failure. A linear regression model of downtime with a reduced number of impact factors, taking into account two main failure types and two main periods of their occurrence during the year, was developed.

The subject of this article are issues related to the navigation system in the field of analyzing the processed signal in the GNSS system receiver. The main purpose of the work is to discuss the Galileo E1 signal processing methods in the GNSS navigation system receiver, supported by adapted research tools in terms of solving the research problem (analysis, model, simulation tests) and the mathematical apparatus used. Key studies are concentrated around the process of generating the navigation data, dispersing sequences and signal modulation. Thus, when designing a receiver, it is better to use the simulation signals than the real ones, since one can get more control over the properties of the received signal. In the final part of the work, in accordance with the subject of research, based on the developed appropriate research tools, observations and final conclusions were formulated, which have practical applications.

Reverse logistics differs significantly from such fields as management of waste, of which the goal is, above all, efficient and effective collection and processing of waste. Therefore, it can be said that reverse logistics refers to such streams of flows in which it is possible to recover the value from discontinued products and situation, in which solution is contribution to a new supply chain. Therefore, in this aspect, the fundamental pillar is transport, in which the crucial element is management of transport process, above all, planning of changes improving this process to better control the degree of their execution.
In this article, the authors examined transport process in a real object in the context of improvement. As a result, practical aspects of planning and control of organization of transport were presented.

This contribution focuses on issue of the autonomous monitoring of selected dynamic parameters of the railway lines test sections under conditions in the Czech Republic. Description of the possibilities of such data collection, including the designed hardware and software, is a part of this contribution. At the same time, the contribution describes application of such a measuring system, comparing the selected dynamic parameters of the two types of switches, the first one was a switch with a standard fastening node, the other one with an elasticized fastening node. Recommendations and conclusions of railway infrastructure manufacturers and railway line managers are parts of this contribution, as well.

The paper deals with web site contents of Municipal Transport Undertakings. In the paper there are introduced kinds of information in use improving and intensifying communication between customers (passengers) and transport operators. These data come from research results of several Municipal Transport Undertaking web sites.There is also mentioned an informative minimum, which is found to be necessary and should not be omitted.

The influence of the aggressive environments of river water, seawater, oil, petrol and sodium hydroxide on the impact strength of epoxy-polyester composite was investigated. Testing was conducted by two different methods. It was determined that the impact strength of specimens that were kept at air was W' = 4.2 kJ/m² (by the second method - W'' = 7.0 kJ/m²). The energy spent on destruction of the control specimen was E = 0.92 J. The main regularities of the crack propagation process in the studied material were found and qualitatively described. The time of a crack propagation (τ = 0.16 μs) was determined. The maximum load, which leads to destruction of the specimen was P_max = 2.47 kN. The comparative analysis of investigated specimens was conducted by the IR-spectroscopy method. It was found, that the biggest decrease in material properties was observed for the specimen that was kept in the petrol environment.

The aim of this research was to conduct the comparative traction tests for T-170M1.03-55 tractor with a flat and elliptical rim. Structurally rational geometry of the crawler's support surface for tractors with semi-rigid suspension is realized by placing the support rollers at different heights relative to the cart. The results of traction tests showed that elliptical track rim has increased the maximum traction power by 10.4%, conditional traction propulsive efficiency coefficient to 7.43% and the specific traction effort by 8%. The increase in indicators is provided by a lower rolling resistance of a tractor with an elliptical rim. Reduction of the resistance power to rolling of the tractor with an ellipse track rim occurs due to alignment of support rollers vertical load and reduction of resistance to rollers movement on internal contours of tracks and in hinges of track chain links. The results of the research indicate a significant improvement in traction performance of T-170M1.03.55 tractors with elliptical track-chain rim.

Based on analysis of the problem of the power supply networks of railways innovative transformation, the direction of research is substantiated related to organization of the optimal strategy of computerized intellectualization of the power supply processes to the railways traction substations. The logical structure of a distributed computer environment developed in the form of graph, which adequately reflects the topology of the organization of the power supply system. A differential mathematical model of the computer architecture of the power supply control is proposed. An intelligent method for finding the optimal strategy for the intellectualization of the power supply processes was proposed to guarantee the specified indicators of the optimal functioning of individual nodes and segments of the power supply management computer network.

The safety of road users is one of the priority issues raised by those involved in vehicle design, latest passive and active safety systems, traffic organization or driver education. Nowadays, an important road safety problem is the behaviour of drivers in emergency situations. In order to measurably estimate the driving quality, parameters such as velocity, acceleration, the way and frequency of using the control pedals are quite often used. This article describes how to assess driver's behaviour based on measurements taken on the road. The frequency of different acceleration ranges during the vehicle drive was determined based on the results obtained. For the arbitrarily adopted acceleration range of - 0.5 - 0.5 m/s2, the driver's working time was over 77 percent on average, with the difference varying significantly between different route sections. Similarly, the study compares the driving times for other ranges of acceleration.

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.

Indonesia's transport sector has experienced rapid growth that has caused excessive fossil fuel energy consumption. Over 2000 to 2016 total final energy consumption in Indonesia's transport sector has grown by 10% per annum so that transport now provides a large and rapidly growing component of total energy use. This study analyzes the specific characteristics of energy intensity in the transportation sector in Indonesia from 2000 to 2016 by employing a multiplicative Log Mean Divisia Index-II. The passenger transport sector in Indonesia, including the four modes of road, rail, water and air is examined in this study. Overall, the decline in energy intensity in passenger transport is attributed to the intensity effect. In passenger transport, the improvement of intensity effect was found to have significantly reduced the overall aggregate energy intensity, while the change in structural effect was found to have a relatively small reduction in the aggregate energy intensity.

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.

Currently the circuit technology of the DC traction power supply system cannot provide the necessary requirements for introduction of high-speed traffic. Numbers of measures and tools have been developed to improve the traction lines that no longer meet current requirements. One of the most promising means for strengthening the traction DC lines is transition to the distributed power supply of the rolling stock. In this article, a comparative analysis was carried out of energy indicators of the classic centralized power system and distributed power systems with use of one aggregate traction substation and with use of the solar generators. That comparative analysis of these systems was performed on a simulation model with the same parameters of the traction line and rolling stock.

Competition in the field of logistics and individual transport services requires the constant analysis of logistics chains and their individual links. Given analysis enables implementation of new approaches to logistics companies and networks trade marketing in the offtake of certain types of goods. Industrial and commercial enterprises have to expand their trade and economic relations with other regions with the aim to provide the necessary sales volumes in the domestic market of regions and to go beyond it. Integration of the country's economy and the free trade policy orientation greatly simplify the task of establishing the free trade and economic relations between producers and consumers. However, there is a question of how quickly and efficiently; with minimal logistics costs, the goods at the right region of the customer should be delivered. The experiment on a one-storey closed warehouse No 3 of Brovary "UVK Ukraine", where a process of the crossdocking warehousing, with subsorting from a warehouse, has been conducted. The warehouse mainly works on trading networks. The loading of the warehouse has been performed with the input flow intensity within (12.3 ... 23.56 (t/h)). During the experiment, the number gain of loading and unloading machines (Electrostacks Reath Track OMG NEOS LAT 3.0) a pcs in the process of unloading, loading and moving consignments, has been examined. In addition, the increasing number of workers employed in non-mechanized forms of work, such as receiving and stacking cargo in the reception area (moving the relevant consignments to designated areas of the reception area and its arrangement), which in total is an increase of 4 employees in the technological process of the warehouse operation, has been investigated during the experiment. The growing of labor and mechanized resources makes it possible to better organize the work of the warehouse, reduce total costs and increase cargo output flow. Conducting the process of warehouse work optimization on the formed technology and corresponding labor and mechanized resources caused an increase of its efficiency. It has been found that the optimal values of intensity of the incoming cargo flow will be 17.93 (t/h); the number of employees engaged in non-mechanized labor - 12 workers, and loading and unloading machines - 3 (pcs). Under such conditions, the warehouse functioning according to the desirability level will reach value 0.792. In this case, the cost value of warehouse work is 181.07 US$/h and cargo output flow intensity is 10.23 (t/h). Results of experimental studies have shown that implementation of the proposed method of increasing the efficiency of warehouse work, based on the company "UVK Ukraine" may, on average, achieve a total cost reduction of 17.2% and an increase in output flow by 34.6% and the input flow by 10.3%.

The transportation industry of a modern city involves the effective systems for the road traffic management. To manage any object is impossible without understanding its specifics. The tasks of road traffic management are based on mathematical models of traffic flows. The "following the leader" model based on the linear dynamic interval of vehicles has become widely accepted in the model analysis. The paper discusses the mathematical model of the linear dynamic interval of vehicles; the model is identified structurally and parametrically. Coefficients of the model are analyzed in detail; a generalized assessment of the dynamic performance of the traffic flow, evolved in various road conditions, is given. The study has resulted in the proposed basic models for traffic flows that can be used for algorithmic support of the model analysis of traffic flows and the road traffic management.

The noise from means of transport is one of the main factors of environmental noise pollution and is one of the factors having an effect on human health. The article presents the problem of noise emitted by urban means of transport. The work focuses on analysis of the acoustic climate in the bus stop zone. In order to estimate the noise level, research was conducted in selected points in one of the Polish cities - Radom. The obtained results allowed assessment of the impact of transport on the noise level in the area of selected bus stops.

The paper deals with the study of stress corrosion cracking of high-strength steels in an aqueous environment with a varying pH factor ranging from 5.5 to 12.0. Steels were studied after quenching and tempering, one of the steels was prone to temper embrittlement. Single-edge notched pre-cracked specimens were used for the experiments. Changes in the pH factor at the crack tip were measured using an antimony electrode. The pH factor values at the crack tip dropped to 2.0. Steel prone to temper embrittlement showed significantly shorter incubation period and more accelerated development of corrosion process compared to the optimized heat treatment of the second steel. Proneness to intergranular fracture was observed close to the fatigue crack tip. The obtained results expand the existing knowledge about localized corrosion processes leading to the refinement of the stress corrosion cracking model when changing the pH factor on the crack tip.

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 study defines criteria and sub-criteria for evaluation of the transport technology for carriage of passengers by railway and road transport. The main criteria are divided into four groups: business, environmental, social and technological, named BEST analysis. Twenty-four sub-criteria have been examined. The method of multi-criteria analysis Decision Making Trial and Evaluation Laboratory (DEMATEL) has been applied to analyse importance and the relations between the criteria. Results show that e criteria of the great importance are business group (29.47%) and technological group (27.49%). The sub-criteria: transport costs for fuel (7.83%); ticket price (8.29%); time travel (6.99%); directness (6.47%) and direct operating costs (6.30%) are the most important. The defined criteria and subcriteria can be applied for evaluation, comparison and selection the transportation variant.

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.