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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 world today is rapidly changing with the spread of automation. Moreover, urban life is more and more common and the number of inhabitants is rapidly growing. This time is the renaissance of bicycle-based vehicles, especially of electric power assisted bicycles. Vehicle sharing is also getting more popular. These progresses will have a crucial effect on traditional transportation networks. Moreover, the traffic volume, parking facilities and public space usage can be drastically modified. A research data is introduced from Paris and Lisbon, which helps to forecast the effect of the autonomous and sharing systems. This evolution can be advantageous, but it can also bring some disadvantages. In this article, these changes are summarized in the mirror of history, especially the Futurama concept and the transport system changes in Los Angeles. This overview will be a good basis for further research and for the development of a routing algorithm.

It is proved that in order to increase the operational characteristics of parts of the river and sea transport, including their physical and mechanical properties, it is advisable to use the protective polymeric composite coatings.
The effect of fillers on the flexural stresses of the developed epoxy composite was analyzed. The critical content of components was determined by the method of mathematical planning of the experiment: the synthesized powder mixture - 0.05 pts.wt., discrete fibers - 0.10 to 0.15 pts.wt. per 100 pts.wt. of epoxy oligomer ED-20. Introduction of such ingredients into the epoxy binder allows to increase the flexural stresses to σ f=77.4…78.6 MPa. The obtained results allow to create materials with improved values of physical and mechanical properties.

With the spread of connected vehicles (CVs), a growth of novel information services exploiting data transmitted by CVs is expected. Wireless communication systems, in particular in vehicular applications, operate with a varying level of transmission reliability, which may affect the quality of V2X-data-driven intelligent transport systems (ITS). Therefore, the performance of ITS should be evaluated in a variety of conditions and the configuration of parameters should be fine-tuned in a safe testbed, using computer simulations. A simple framework is presented, which couples VISSIM traffic simulation and OMNeT++ communication networks simulation in real time, enabling an assessment of the relationship between a communication reliability and transport service quality. A functionality of the framework is demonstrated by applying it to a scheme controlling signalized intersections while estimating traffic flows from the V2I data.

In many applications, where rotating machines of high power are used, high demands on reliability and safety are laid. Precise manufacturing procedures has to be kept even in case of machines retrofits when e.g. rotors are newly assembled. Even small inaccuracies or misguiding the precise technological procedure can lead to improper running of the machine and it can result in shut-down of complete drive. In case of primary circuits of nuclear power plants, it further means the shut-down of the whole power plant. Consequently, it results in significant financial losses (foregone profit and cost given by problem fixing). The paper presents a methodology of vibration origin investigation in case of large rotating machines which are part of drives like pump, compressors etc. The methodology is based on the detection of undesirable vibration using a diagnostic system on-site and further it uses mathematical modelling of corresponding mechanical parts to reveal the vibration origin. The modelling along with the measurement showed that the detected dangerous vibration is caused by misguided assembling of the rotor of the machine.

The presented research work analyzes the sensing system, the main aim of which is a raster formation and controlling this process using the optical measuring equipment and high precision angle encoders. Optical measuring equipment are used for the raster position detection, meanwhile angle encoders for controlling the tape speed. The main parameter of raster formation process is fixed transportation speed, but there are difficulties to realize it, because there is imperfection of the device elements. The article analyzes the dispersion of vibration accelerations of the raster formation device and tape in the two directions (transverse and longitudinal) and presents an analysis of their parameters in application of the theory of covariance functions. The results of the measurements of vibration accelerations at the fixed points of the device constructions and the tape were recorded on a time scale in the form of digital arrays (matrices). Values of auto-covariance and inter-covariance functions of digital arrays of the vibration accelerations measurement data were calculated by changing the quantum interval in a time scale. The developed software Matlab 7 in operator package environment was used in the calculations.

Use of the powder metallurgy (PM) in production of various components has been growing in the automotive industry, including production of sintered stainless steels (SSSs). This study aims to improve the functional properties of SSSs by formation of the Cr3C2-NiCr coating by APS method. The next stage involved alloying of the surface of SSSs using the gas tungsten arc welding (GTAW). Analysis of microstructures was carried out using microscopy (metallographic microscope and scanning electron microscope). Furthermore, the study presents XRD (X-ray powder diffraction) examinations, mechanical properties and surface roughness measurements. The presented modification improved properties of the surface layers examined in the study and enabled a reduction in the wall thickness of the detail, which is important factor in the automotive and transport industry.

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.

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.

The paper presents a simulation model of a loading unit dynamics, with a layered structure, wrapped with a stretch film. Stretch film wrapping is the most commonly used and cheap method of securing the load unit. The model, proposed by the author, allows assessing the stability of the unit during the transport operations, when the loading unit is subjected to inertial forces. Deformations of a unit and prediction of its disintegration in extreme cases can be evaluated based on results of a simulation. The value of the necessary containment force as well as the number of wraps with the pre-stretched film, can also be estimated. In effect, simulations can reduce the amount of film used and the number of stability tests performed experimentally.

The paper presents a study of the vertical vibrations of a bogie of a passenger vehicle, based on the acceleration of the axles and the bogie frames, measured during the running at a constant velocity. To this purpose, the root mean square (RMS) acceleration is calculated for more measurement sequences at different velocities. In principle, the RMS acceleration increases along with the velocity and influence of the variability of the amplitude in the track defects upon the dispersion of the values in the RMS acceleration. Based on the spectral analysis of the measured acceleration, wheel defects and undulatory wear of the rolling surfaces of wheels and rail are highlighted.

The article is devoted to influence of the clay thixotropic solutions on the strength of resistance to movement of the earthmoving machines' working elements.
The forces of resistance to the movement of a flat plate, a smooth cylinder and real working bodies in a clay solution for various modes of solution flow (bingamian, pseudo-laminar and turbulent) are established.
Mathematical models of movement of the earthmoving machines working elements in clay solution are developed and investigated.
Dynamics of the working element of an earthmoving machine movement in a clay solution is studied. Dependence of the feed force, torque and dynamic coefficient on the resistance forces, acting on the working body from the clay solution, is established.

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.

Year 1956 was an important year for international road and freight transport. By this year Convention on the Contract for the International Carriage of Goods by Road (CMR) was made. The basic purpose of the Convention was to unify the rules in the international carriage of goods and thereby promote development of international trade. From the practical point of view, this was very important for both carriers and transporters. This Convention also describes the most important document in the international carriage of goods, which includes the consignment note of CMR as well. Recently this document is often associated with the term neutralization. Objective of this article was to clarify the meaning of this phrase in transport. In addition, the aim was to find out in what range carriers have real experience with neutralization of the consignment note of the CMR during the transport, for what types of goods and on what types of routes is the neutralization being used the most.

The article provides a brief description of the digital integrated transportation support environment. The methods of choosing the base route in the formation of transport networks in the conditions of the formation of a digital integrated environment are presented. It is shown that the means of solving the problem of optimization of transport networks is a developed modeling complex, which consists of a set of models with the necessary degree of detail. The paper presents a functional diagram and a brief description of the complex. The complex functions taking into account the replenishment, improvement and updating of models, allow you to combine different types of models and use the necessary of them when solving specific problems of transport network optimization. The modeling complex allows to significantly simplify the optimization of transportation networks. On the basis of the proposed mathematical apparatus, the software of an automated system has been developed, which is designed to function in a digital integrated environment, a brief theoretical description of which is given.

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 practical problems that usually come up during the on-vehicle testing of motor car shock absorbers have been discussed. Results of example tests carried out to the EUSAMA standard procedure were compared to the test results obtained with using newer methods, i.e. the phase angle method and half power bandwidth method (HPBM). The issue of incompatibility of the typical excitation applied by diagnostic suspension testers with one that often occurs in the road conditions has also been raised. It has also been shown that the wear of shock absorbers may affect the value of braking deceleration of cars with ABS (anti-lock braking system) when moving on uneven ground.
The main objective of the work was to assess usefulness and reliability of various diagnostic methods intended for the on-vehicle testing of car shock absorbers.

This study aims to assess the determinants of the labor market in the Greater Jakarta Area (Jabodetabek) with a population of 27.9 million (2010 census) and growth rate of 3.6 percent per annum over the period 2000-2010. With a total area of 4,384 square kilometers (1,693 sq mi), the city has a very high population density of 14,464 people per square kilometer (37,460/ sq mi), while the metro area has a density of 4,383 people/sq km (11,353/sq mi). The paper employs the survival regression analysis by incorporating attributes of commuter, namely gender, age, distance, travel time, wages, stress, education level, double income households and home ownership. The area consists of Jakarta as the receiving labor market and eight municipalities and regencies as labor suppliers. The study utilizes a cross-section data from a commuter survey with more than 4,000 respondents participated using different modes of land transport. The results reveal that some determinants have influenced commuters' resiliency and their willingness to participate in the receiving labor market. This study found that gender, distance, wages and home ownership do not affect the respondent's decision whether to stay or quit as commuters. On the other hand, the fittest model exhibits that age, education level, stress, travel time and double income households have significant effects on individual's decision to stay or quit as a commuter. It is found that gender, distance, wages and home ownership do not matter for respondent's decision on whether to stay or to quit as commuters. The model exhibits that age, education level, stress, travel time and double-income household have significant effects on an individual's decision to stay or quit as a commuter. Education level has a positive effect; on the other hand, age, stress, double-income household and travel time have a negative effect. The policy implications for improving the labor supply provision and some contested policy options are suggested, such as the provision of affordable housing in Jakarta, the improvement of commuting enjoyment, the establishment of child care facilities in the office buildings and the creation of more sophisticated jobs within the Jakarta's surrounding municipalities and regencies.

Genetic algorithm (GA) is an efficient tool for solving optimization problems by evolving solutions, as it mimics the Darwinian theory of natural evolution. The mutation operator is one of the key success factors in GA, as it is considered the exploration operator of GA.
Various mutation operators exist to solve hard combinatorial problems such as the TSP. In this paper, we propose a hybrid mutation operator called "IRGIBNNM", this mutation is a combination of two existing mutations; a knowledgebased mutation, and a random-based mutation. We also improve the existing "select best mutation" strategy using the proposed mutation.
We conducted several experiments on twelve benchmark Symmetric traveling salesman problem (STSP) instances. The results of our experiments show the efficiency of the proposed mutation, particularly when we use it with some other mutations.

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.

This article presents an approach of improve logistics processes with the system dynamics modeling of two different processes scenarios. System dynamics is used, not only as a causal loop diagram, but calculated measures of end-user satisfaction indicators were provided by experts, as well.
Literature review of fundamental definitions and recent ideas in subject of supply chain management (SCM), system dynamics (SD), business processes model and notation (BPMN) and distribution logistics for dozens of major sources, has been made.
In the work, methods of expert interviews, content analysis of recent publications, system-dynamic modeling and business process modeling, were used. Developed BPMN-models of distribution logistics business processes are given in Appendices #1 and #2.

Characteristics have been developed, by which the boundaries of coherence of adjacent road sections are established in accordance with requirements for the traffic safety. The coordination of adjacent sections of the road is carried out taking into account the driver's behavior program, which is presented in the work as a value of the maximum entropy of his perception field. The choice of this criterion is determined by the possibility of a comprehensive assessment of many road environment factors that influence the driver. The boundaries of coordination of the maximum entropy values of adjacent road sections with use of the accident rate are established.

The main aim of the paper is the analysis of simulation model reflecting selected in-warehouse logistics processes in the aspect of their availability. For this purpose, one-aisle machine picking problem with use of a stochastic random simulation is studied, with a special focus on reliability of the system to disturbances and maintenance scheduling. The methodology in the research consists of classic measures of reliability. The model is designed in order to analyze availability of selected parameters of randomly generated order picking process. One of key-results of the paper is answer for question if a mean time to failure can be treated as a value of time when the first failure in the system occurs. A summary of the contribution includes discussion and the perspectives for further research in the subject matter.

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.

In recent years, there has been a significant increase in the number of buses operated by urban public transport companies powered by alternative fuels and equipped with alternative drive systems. In addition to economic factors, operators should also take environmental aspects into account when purchasing new vehicles. In this case, a useful criterion for selecting a vehicle is the Life Cycle Cost (LCC), which, in addition to the cost of purchasing a bus, takes into account the necessary expenses associated with its maintenance, operation, decommissioning, as well as emissions costs. This paper presents a study of the LCC values, estimated for the entire bus fleet based on several bus replacement variants, taking into account different shares of alternative buses in the transport fleet. Analyses have shown that replacing conventional buses by the compressed natural gas (CNG) powered buses will reduce life cycle cost by 27% compared to the LCC level in 2019. Increasing the share of electric buses in the fleet will significantly reduce the level of emissions of harmful substances contained in exhaust gases.

General mobility estimation is demanded for strategy, policy, systems and services developments and operations in transport, urban development and telecommunications. Here is proposed an individual motion readings collection with preserved privacy through loosely fit smartphones, as a novel sole inertial sensors use in commercial-grade smartphones for a wide population data collection, without the need for the new infrastructure and attaching devices. It is shown that the statistical learning-based models of individual mobility classification per means of transport are capable of overcoming the variance introduced by the proposed data collection method. The success of the proposed methodology in a small-scale experiment for the Individual Mobility Classification Model development, using selected statistical learning methods, is demonstrated.

Modelling of vehicle's motion is one of the solutions applied in the research of automotive safety. There is always a discussion which model should be used for computer simulation. Models with higher number of degrees of freedom require identification of many parameters, which are usually difficult to obtain. So, very often relatively simple flat model of vehicle's motion is applied. It needs only such parameters as mass of a vehicle, location of centre of gravity from front and rear axle, yaw mass moment of inertia and side slip characteristics of the front and rear axle. In this paper the upper mentioned model was applied, considering different side slip characteristics of the front and rear axle. The scenario of vehicle's motion was based on random changes of steering wheel angle during the road test, recording signals from on-board CAN (Controller Area Network) bus of automobile simultaneously, which were further applied in simulation.

The paper presents the methodology behind the statistical selection of input parameters using the example of spraying two cold-sprayed coatings. The Ti and Cr3C2-25(Ni20Cr)-Gr coatings were tested. Despite the large difference in the structure of these coatings, nanoindentation studies were carried out focusing on the nano hardness H and elastic modulus E. Based on the four input parameters and two output parameters, a 2-level factorial 2(k-p) experimental design was performed. The conducted analysis showed the significant influence of the spray distance on the H and E values in the case of the Ti coating. The input parameters of the spray distance and the type of carrier gas used turned out to be statistically significant in the case of the cermet coating. Taking into account the statistical analysis, the coatings were sprayed with modified values of the input parameters.

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%.

Raceway curvature ratio is a very important parameter, because its values influence the performance characteristics of rolling-element bearings, their durability and the level of generated vibrations. However, the level of generated vibrations is one of the most important operating parameters of the rolling-element bearings. Excessive vibrations generated by rolling-element bearings affect the operation of the whole mechanism. The article presents experimental studies aimed at evaluation of influence of the inner and outer raceway curvature ratios of 6304-type rolling-element bearings on generated vibrations values. The raceway curvature ratio was determined based on results of metrological measurements. For this purpose, the radii of the inner and outer raceways as well as the diameters of the balls were measured. Design and principle of operation of an innovative system for analysis of the raceway geometry of the rolling bearing rings was presented. The vibration analysis was carried out in three frequency ranges, i.e. low (50-300 Hz), medium (300-1,800 Hz) and high (1,800-10,000 Hz). Values of measured vibrations were expressed in Anderon units. The test results showed that increase in the raceway curvature ratio causes a moderate decrease in the value of the generated vibrations. The research results presented in this article will serve as a guidance to designers and manufacturers of the rolling-element bearings on how to modify the geometry of raceways and balls to obtain bearings that generate low vibration values. That is very important in car transportation.