Scientific Journal of Silesian University of Technology. Series Transport

6

Authors: Radka JÍROVÁ, Roman SVOBODA, Lubomír PEŠÍK

The paper deals with reducing vibrations transmitted from electric golf cart wheels to the seat and the seated person. These vibrations appear while driving a golf cart on uneven terrain of a golf course. This problem can be solved by using the elastic and damping link between the cart frame and seat, which is tightly connected to the electric power battery. A mathematical calculation is used to evaluate the designed solution in which the golf cart is defined as a system of masses connected with elastic and damping links. The result of the designed solution’s mathematical description provides a reference step response of the golf cart seat.

7

Authors: Václav ZOUL, Petar KOVÁČ

Torsional vibration calculation (TVC) is among the basic calculations that are required to support propulsion projects for various vehicles, ships and construction machines. A number of powerful software packages for these calculations already exists. However, the need to respect the physical properties of propulsion systems that are more complex than before has arisen. At the same time, knowledge about system properties and the capabilities of computing systems are also growing, resulting in an increase in new software systems, which could be used for these calculations. In this paper, these new trends are briefly described, with attention paid not only to practical use, but above all to how and to what extent these themes should be presented to students.

9

Authors: Vladimir DEKYS, Pavol KRISKA, Ladislav LIETAVA, Peter KOPAS, Ondrej STALMACH

The article presents a procedure for vibration analysis of the device based on measured data in simulated operating modes. Subsequently, the criterion of fatigue damage is formulated because this mechanism can be induced or accelerated by recognized operating deflection shapes. The criterion is used to select an optimal set of control device parameter values, which control each device’s operating modes and transitions between these modes and affect the excitation of the frame vibration due to possible shocks in the system. The criterion is formulated based on the vibration displacement processing from these dynamic measurements, the modified Goodman and Palmgren-Miner rules, and the results of static computational analyse. This criterion compares the effect of damage to the modes that control these sets of parameters, while the selection of the optimal control set is performed. At the end of the article, the limitations resulting from the simplifications used are described. The application of this procedure is also useful, for example, when further data are obtained by subsequent experimental stress-strain analysis methods and when we want to reduce the number of possible operating modes by which we carry out subsequent measurements among the most damaging modes.

10

Authors: Grzegorz ILEWICZ, Andrzej HARLECKI

The article describes the method for the multi-objective optimization of a proposed medical robot model, which has been considered in the form of a serial kinematic chain. In the assumed approach, the finite element method was used in order to model the flexibility of manipulator links. To speed up the optimization process, the response surface method was applied, defining the socalled metamodel. In order to uncover the optimal solution, a multi-objective genetic algorithm was used, guaranteeing the optimality of the manipulator model in the Pareto sense. The optimization process was carried out by analysing the selected case of the manipulator’s dynamics. The proposed optimization method allows us to minimize the mass of the manipulator while additionally ensuring the highest possible stiffness of its structure and sufficient strength of its parts. Furthermore, it offers the possibility to eliminate the natural frequency of vibrations of the model close to the resonant frequency.

10

Authors: Miloš NĚMČEK

The standard ISO 6336 for the calculation of load capacity of spur and helical gears was introduced in 2006. There were some later amendments, but several typographical and other errors. These can cause some misunderstandings during applications of the standard and are irritating for its users. This contribution seeks to highlight some aspects of the use of this standard, as well as drawing users’ attention to the errors it contains and, at the same time, properly worded content. To fully appreciate this article, the reader is advised to have a copy of the standard itself. Parts 3 and 6 of the standard are covered in the contribution.

10

Authors: Vladimir SHPACHUK, Aleksandr CHUPRYNIN, Tatiana SUPRUN, Andriy KOVALENKO

Mechanical models of “railroad car-track” transport system for each phase of motion are developed. Particularities of dynamic interaction between the four-axle car and the track are studied by considering four phases of motion over joint irregularity. Methods for solving differential equations of the discretecontinuous system fluctuation are developed. Numerical analysis is used to determine deflections of the trailing rail under the first sleeper for each phase of motion depending on motion phases, and car load and speed.

11

Authors: Peter KAŠŠAY

Nowadays, there is increasing demand for the use of renewable energy sources such as woodchips. One of the important qualitative parameters of woodchips is the size distribution. The aim of this article is to determine the effect of a woodchipper disc’s torsional vibration on the evenness of woodchip length, as well as propose a mathematical solution to this problem by assuming one harmonic component of disc speed and the uniform feed of chipped material. The presented mathematical solution can be used to determine the unevenness of woodchip length when the parameters of torsional vibration are known.

13

Authors: Jaroslav HOMIŠIN

The contribution briefly approaches the author’s profile in the field of scientific research during his work at TU in Košice. More precisely, it presents a selected, specific area of torsional oscillation of mechanical systems concerning the characteristics, research and application of new elements, i.e., so-called pneumatic tuners of torsional oscillation (pneumatic couplings), a field that the author has long been devoted to. In the process, the article informs the reader about the development of new types of flexible shaft couplings, i.e., tangential and differential pneumatic couplings (also with autoregulation), presents the results of static and dynamic measurements made on certain couplings with the interconnection of pneumatic flexible elements and draws attention to the conditions involved in the application of these coupling types in torsionally oscillating mechanical systems.

14

Authors: Marek RUTKOWSKI

The article explores the stress-strain state of the pneumatic flexible shaft coupling of the tumbling mill drive using a software of finite element analysis. The study has revealed that the stress-strain state of the pneumatic flexible shaft coupling is characterized by an uneven general and local distribution of stresses. Areas of maximum stress and strain in the pneumatic flexible shaft coupling have been defined. The study allowed for changing the geometry and reducing the mass of the disc of the pneumatic flexible shaft coupling with a slight change in stresses and strains. The results of the study can be applied to the design of pneumatic flexible shaft couplings and serve as a basis for further research.

18

Authors: Erdem DOGAN, Ersin KORKMAZ, Ali Payidar AKGUNGOR

Short-term traffic estimations have a significant influence in terms of effectively controlling vehicle traffic. In this study, short-term traffic forecasting models have been developed based on different approaches. Seasonal autoregressive integrated moving average (SARIMA), artificial bee colony (ABC) and differential evolution (DE) algorithms are the techniques used in the optimization of models, which have been developed by using observation data for the D-200 highway in Turkey. 80% of the data were used for training, with the remaining data used for testing. The performances of the models were illustrated with mean absolute errors (MAEs), mean absolute percentage errors (MAPEs), the coefficient of determination (R2) and the root-mean-square errors (RMSEs). It is understood that all the models provided consistent and useful results when the developed models were compared with the statistical results. In the models created separately for two lanes, the R2 values of the models were calculated to be approximately 92% for the right lane, which is generally used by heavy vehicles, and 88% for the left lane, which is used by less traffic. Based on the MAE and RMSE values, the model developed by the ABC algorithm gave the lowest error and showed more effective performance than the other approaches. Thus, the ABC model showed that it is appropriate for use on other highways in Turkey.

8

Authors: Agnieszka FORTOŃSKA

The author will discuss the bird strike phenomenon and its impact on the air transport of passengers. In addition to the above, examples of flying accidents mainly caused by bird strikes will be provided. Furthermore, the issue of responsibility for accidents caused by bird strikes will be discussed, alongside legal regulations pertaining to subjects connected with the topic.

8

Authors: Elżbieta MACIOSZEK, Damian LACH

A detailed analysis of traffic conditions at the intersection allows us to obtain information about the efficiency of its operation. This type of analysis usually involves assessing the capacity and scale of the intersection and applying classical measures to assess its quality. In Poland, for this purpose, methods developed by the General Directorate for National Roads and Motorways are used to estimate the capacity of intersections without traffic lights, intersections with traffic lights, and roundabouts. The paper presents the results of the analysis of traffic conditions at the intersection of Brzezinska and Nowochrzanowska Streets, located in Myslowice (Silesian Province, Poland). The paper also examines the findings on traffic safety at this intersection.

8

Authors: Igor VAKULENKO, Nikolajj GRISCHENKO, Leonid VAKULENKO, Vasily EFREMENKO, Svetlana PROIYDAK, Oleg PERKOV

The technological use of accelerated cooling makes it possible to improve the carbon steel properties of the all-rolled railway wheel disc. The properties’ complex depends on the temperature of the accelerated cooling termination. This is determined by the ratio of the carbon atoms emitted from the supersaturated solid solution to the crystal structure defects and dispersion strengthening from carbide phase particles. If the cooling stops at a temperature above 350°C, the decline rate of the strength properties increases. This is caused by the excessive softening effect of the solid solution breakdown and cementite spheroidization during the processes of dispersion hardening.

9

Authors: Agata MICHTA, Tomasz HANISZEWSKI

Transport noise is one of the biggest problems faced by urban agglomerations. Therefore, more and more activities are being undertaken related to its reduction. The article attempts to investigate the noise level on public transport vehicles, buses, trams and passenger cars, from the passenger’s perspective. The assessment is based on the results of field tests. The study considered wheeled and rail vehicles, including a new generation of buses and tramways, as well as a car subjected to many years of operation. The research was carried out in the city of Katowice. The conducted experiment showed comparable high values for recorded volume levels on trams and buses, as well as a relatively low noise level in the passenger car.

10

Authors: Jacek BARCIK, Piotr CZECH

The cross-border transport of soldiers and military equipment is particularly difficult and characterized by a distinct difference with civil transport. For its implementation, political will is needed, in line with the tolerance of representatives of foreign armed forces on the territory of the state, as well as adequate transport capacity and infrastructure capable of ensuring transport efficiency. These circumstances are particularly important in the case of alliance cooperation within NATO in the Euro-Atlantic subregion. Legislation within the organization is designed to ensure coordination of military transport activities. However, the procedures currently in place are criticized as being too rigid and failing to provide a quick transfer of forces and resources in the event of a sudden threat to one of NATO’s allies. For this reason, there have been calls to create an allied “Schengen military zone”, in which the Schengen Agreement would be abolished, internal controls and administrative hindrances between NATO countries would be lifted, and the free transport of soldiers and military equipment would take place. The aim of this article is to examine the feasibility of implementing this proposal and to identify the basic difficulties involved in carrying out military transport within the NATO context. A question arises about the possibility of creating a “Schengen military zone” for NATO. The aim of the article is, firstly, to present NATO legal sources governing the issue of military transport. In the next part of the analysis, allied military transport procedures will be analysed, accompanied by a critical identification of potential shortcomings. The article concludes by providing answers to the research question.

10

Authors: Sonia WIECZOREK, Katarzyna PAŁKA, Beata GRABOWSKA-BUJNA

The article deals with the issue of railway transport safety from a strategic aspect. In turn, the concept of developing railway transport safety and the possibility of transferring model solutions to the economic field are presented. The article also focuses on highlighting the most significant criteria in terms of the development of railway safety. All stages in the realization of a relevant strategy are characterized, with a particular emphasis on the conditions for their efficient implementation.

11

Authors: Grzegorz SZALA, Romuald FAJTANOWSKI, Piotr GRYGORKIEWICZ

The paper explores the relationship between the design and construction process for technical objects and industrial design based on an analysis of selected examples of conceptual designs for two-wheeled vehicles. These examples have been taken from a collection of projects implemented by design students and graduates in the Faculty of Mechanical Engineering of the University of Science and Technology in Bydgoszcz. The paper presents didactic aspects of the issues connected with design and its relation to the design process for technical objects.

12

Authors: Eva FALTINOVÁ, Martin MANTIČ, Jozef KUĽKA, Melichar KOPAS

This paper focuses on a reliability analysis of various structural variants of a crane lifting mechanism. The reliability of such a mechanism is a basic requisite for the safe operation of the crane as a whole. The article analyses and jointly evaluates structural solutions for the lifting mechanism in a bridge crane, in order to emphasize the technical aspects of system reliability in this context.

12

Authors: Branislav ŠARKAN, Tomáš SKRÚCANÝ, Štefánia SEMANOVÁ, Radovan MADLEŇÁK, Andrzej KURANC, Marie SEJKOROVÁ, Jacek CABAN

A coast-down test is carried out in cases when there is a need for the exact expression of the forces acting on a road vehicle during its coast-down. These forces act mainly against the vehicle’s movement due to air and tyre rolling resistance. Knowledge of the course of these forces throughout the vehicle’s movement range is also a requirement when measuring fuel consumption with a roller performance dynamometer. The reason is that this device has to load the rollers by force or performance corresponding to the given vehicle, while testing it during various driving cycles. For approval purposes, the requirements for this type of test are described in the applicable regulations, i.e., UNECE Regulations No. 83 and No. 101, or the newly developed Worldwide Harmonized Light Vehicles Test Procedure (WLTP). Slovak Technical Standard STN 30 0556 also contains detailed procedures for carrying out the test. The authors of this paper have taken into account both types of technical regulations in order to conduct coast-down tests on chosen vehicles. The results are usable in terms of measuring fuel consumption on a roller dynamometer. Furthermore, the vehicle’s economic performance in normal operation mode can be also assumed with these results.

13

Authors: Wojciech REDO

This article highlights the specifics of on-board recorders among the various systems found on aircraft. Attention is drawn to the legal and technical compliance requirements concerning modern on-board recorders. Reference is also made to certain aspects of recording methods and data security. Furthermore, the paper especially focuses on the process of measuring a parameter, indicating the basic criteria regarding the accuracy of the measurement. In addition, the role of two essential elements in the measuring chain is discussed: the feeder as a parameter measurer and the transformation system, i.e., AC converter.

16

Authors: Marek RUTKOWSKI

The purpose of this paper is to examine the process of building, repairing and maintaining two types of main roads in the Kingdom of Poland, especially during the mid-19th century, when the overall process of expanding the local road transportation network started to considerably slow its pace. Publicly announced parts of official government reports have been taken into consideration in order to describe such endeavours by the Polish transportation authorities concerning first-class and secondary routes (generally paved with the usage of a standardized macadam system) during the period between 1843 and 1859.

8

Authors: Laurian GHERMAN, Constantin ROTARU, Marian PEARSICA

The paper analyses a new configuration of an electromagnetic launch system (EMLS) able to accelerate a 1-kg mass projectile at a muzzle velocity of 3,000 m/s with an acceleration length of 10 m. The analyses consist of a mathematical calculation of the value of acceleration force necessary to achieve the project objectives. Based on these results a new configuration of an EMLS is presented. The projectile is accelerated by the Lorentz force where the magnetic field is created by permanent magnets made of neodymium iron boron (NdFeB). The permanent magnets are arranged in a cylindrical Halbach array with a uniform field inside. The copper wire coils have a special design, which produce a large acceleration Lorentz force with a current under 1,000 A. A short comparative0 analysis shows the advantages of this new solution compared with well-known accelerators such as railguns and coilguns. In the next part of the paper, we present the results of a simulation of this configuration with an interactive software package based on the finite element method used to analyse and solve three-dimensional electromagnetic field problems and simulate the movement of the projectile. These results confirm the advantages of this new configuration and open the way to test the system under laboratory conditions. At the end of the paper, conclusions are presented. This new EMLS, based on Halbach array configuration, can be used as a catapult for UAVs, airplanes or missiles, as a mass driver for small satellites or as a gun, which is a better solution than railguns or coilguns.

8

Authors: Paulina RUTKOWSKA, Mariusz KRZYŻANOWSKI

Aviation is the fastest growing but also the safest mode of transport. International aviation organizations give the highest priority to safety while creating aviation regulations. Therefore, a safety management system (SMS) has been created. Two approaches to assuring safety in aviation may be distinguished: Safety-I and Safety-II. Safety-I is the standard approach, focused on processing the information about malfunctioning features and system elements. On the other hand, Safety-II is a new approach to safety management, based on identifying the elements or functions of the system that work properly, which enables the system to confirm resilience to undesirable effects. One of the methods utilized for the Safety-II approach in order to study complex sociotechnical systems is the FRAM (functional resonance analysis method). The method is focused on analysing daily activities in various conditions in order to create a model of work performance. The models created based on the FRAM can be used for risk analysis, accident investigations and predicting possible future events affecting aviation safety. This method allows us to simulate system constraints and uncertain states. It can also be used as support for the air traffic safety management processes based on the Safety-II approach. The following article presents a developed FRAM model for the transfer of control over aircraft. This model constitutes an example of a coordination scheme limited to basic activities of air traffic control (ATC) services, providing a general framework for the construction and operation of the FRAM model.

9

Authors: Petr CHLÁDEK, Dana SMETANOVÁ, Srećko KRILE

This paper is devoted to the Travelling Salesman Problem as applied to Czechoslovak ocean shipping companies and their marine ports on the Black Sea. The shortest circular path around these ports is found and discussed. Formulation of the problem accounts for the fact that distances between the individual cities are not the same in both directions. The consequences that arise from this situation are studied. The used algorithms are based on graph theory and standard logistic methods. In addition, the results are compared with the results obtained by using a minimum spanning tree algorithm.

9

Authors: Katarzyna RADZIEWICZ, Krzysztof GARBALA, Michał CEGŁOWSKI

This article presents the results of homologation tests of an LPG reducer. Due to the material requirements of the LPG reducer in this case, the R02 reducer, designed by the joint-stock company AC Spółka Akcyjna, is used. Test procedures, which must be carried out, are also presented and generally explained with specified conditions for conducting the processes. The advantages of using the R02 are also presented. The properties of aluminium alloy 226, which is the body of the reducer, are characterized and are divided into four groups: technological features/qualitative indications, physical properties, mechanical features and chemical composition. The whole article is summarized with appropriate conclusions.

10

Authors: Paweł GOŁDA

The article presents the key processes taking place in the area of the airport’s plate. The need to look for effective methods and tools supporting decision-making in the area of improving the efficiency and effectiveness of airport operations is pointed out. In addition to efficiency, reliability and the level of costs generated, work safety is an important aspect in the organization of airport operations. Work safety during the implementation of airport operations is one of the basic factors affecting the design and organization of airport systems. A graph of the airport panel structure is proposed and the decision problems regarding the taxiing of the aircraft on the apron and handling of the ship after landing are indicated.

11

Authors: Paweł DROŹDZIEL, Pavlo POPOVYCH, Tetiana VITENKO, Oksana SHEVCHUK, Roman ZOLOTYI, Oleksandr KONONCHUK

Support frameworks of transport vehicles operate under varying terrain conditions under the influence of extreme climate and corrosive environments. When transporting cargo, dust is deposited on the surface of metal structures. The combination of dust and moisture creates an aggressive environment resulting in intense corrosion damage. The damage is caused by the defects of corrosion pitting, which occur on the surface and transform into corrosion cracks. Based on energy approaches, with the application of wellknown results for the mathematical description of electrochemical reactions and the principles of fragile fracture mechanics, an analytical model of durability is proposed for the first time. The model determines the residual life of maximum loaded elements of undercarriages with surface cracks under the action of dynamic loads and corrosive environments. For this case, a set of mathematical relations in the form of a non-linear differential equation was developed, as well as the initial and final conditions for determining the life of vehicles’ structural elements with corrosive surface cracks. The analytical model implementation is proven by solving the problem of determining the residual life of a vehicle’s element, i.e., a steel plate, weakened by a semi-elliptical surface crack, which is under the action of dynamic loads in a 3% sodium chloride solution. The insignificant increase in the crack’s initial size is proven to greatly reduce the period of its subcritical growth. The developed model was applied to define the residual life of thin-walled elements of structures with surface cracks.

12

Authors: Emil AUGUSTYN, Adam KADZIŃSKI, Piotr SMOCZYŃSKI

The Tactical Aircraft Operating System (a system for tactical aircraft operational usage) constitutes the main research area of this paper. The authors present this system via an innovative model for an anthropotechnical system in the format of an aggregated analysis domain. This model constitutes a detailed explication of a fragment of the existing Tactical Air Force System metamodel at the level that concerns tactical aircraft operation systems. The aggregated analysis domain for tactical aircraft operations is built on seven single-analysis domain, each of which includes a series of processes, operations and events, related to the airman’s aviation activities cycle, what happens during an air mission and when an aircraft operating cycle is carried out. The subsequent individual analysis domains are connected to each other by an airman-aircraft anthropotechnical pair. The introduced method of modelling the Tactical Aircraft Operating System ensures the desired generality, comprehensiveness, coherence and transparency of such a model, which allows for its implementation in various types of tactical aircraft and tactical air force bases. In principle, within the presented considerations, the model is described in relation to a single aircraft operating cycle, which is carried out by one airman during a single air mission. However, the authors have taken care when creating this model structure, so that its implementation in more complex aircraft operating cycles (more than one aircraft and one airman) is possible. Apart from the analysis domains (“before take-off”, “departure”, “air task”, “arrival”, “after landing”), which are closely related to the essential aircraft operations, the model also includes the analysis domains associated with air mission preparations and summaries. The model for the Tactical Aircraft Operating System is described by the authors in textual form, as well as in tabular form. The presented concept constitutes an attempt to formally notate the Tactical Aircraft Operating System model, in which each of the individual analysis domains can be treated as an area of interest for hazard risk management processes within the Tactical Air Force System.

12

Authors: Bożena SZCZUCKA-LASOTA, Tomasz WĘGRZYN

The goal of this paper is to analyse the mechanical properties of the weld steel structure of car body truck frames following MAG welding repairs using various filler materials. The main role of welding conditions is connected with filler materials, welding technology, stress state and temperature. In the paper, the properties of steel structures after MAG welding with microjet cooling are presented. Weld metal deposits (WMDs) were prepared by using various welding wires with different chemical compositions. A WMD with various nickel content was examined using three different welding wires; simultaneously, a WMD with varied oxygen content was examined using different gas mixtures for microjet cooling. In this study, the metallographic structure and impact toughness of welded joints were analysed in terms of welding parameters. The amount of acicular ferrite (AF) in WMDs, with various amounts of nickel and oxygen after welding, was tested. The various steel deposits were checked with the variable content of manganese and silicon, as well as nickel. Gas mixtures of argon and carbon dioxide were used for microjet cooling.

17

Authors: Volodymyr SAKHNO, Victor POLIAKOV, Igor MUROVANYI, Vadim SELEZNIOV, Yuriy VOVK

The objective of the article is to determine the transverse stability indexes of hinge-connected buses (HCBs) by applying the computation-analytical method. The transverse stability parameters of hybrid buses with active trailers are analysed. Based on these parameters (the angles of the roll and redistribution of loads on the sides), the analytical dependences are developed. The dependences describe the movement of the parts of HCBs in the vertical plane. Considering the action of longitudinal and transverse forces, the roll angles of the bus and the trailer were determined. The limiting angle of the side roll of the bus rollover was found to be амах = 27.560 мах, and the trailer rollover to be амах = 30.210 . The obtained transverse stability indexes of HCBs with a hybrid power plant testify to the compliance with the standard DSTU UN/ECE R 111-00.

19

Authors: Zbyšek KORECKI, Vladimír SMRŽ, Jan BOŘIL, Miloslav BAUER

Using new technology to track service movement and logistics equipment, passengers or wild animals in the airport area can significantly reduce runway incursion occurrence. Sensor implementation networks will allow for foreign entity identification in a timely manner and take measures to prevent unauthorized access to the track. Modern technologies, which include sensor networks, multifunctional camera systems and radio frequency identification access chips facilitate the creation of complex safety nets at active points and on access roads. Due to their mobility and possible changes in range and direction, sensory networks are an effective method for achieving the desired level of security. Combining elements of modern technology creates space for automated airport security. Security risk portfolios are now defined for 10 different operating domains and give advice to the decision-making process, which the European Plan for Aviation Safety (EPAS) has supported. The aim of the article is to analyse safety in commercial air transport for the period 2006-2015 in comparison with 2016 and propose a method that would reduce the number of incidents through sensor networks and using texture analysis.

6

Authors: Adam WOLSKI

Growing trade and the globalization of production and consumption have contributed to the increased importance of seaports. Maritime transport of bulk cargo is competitive. The carriage of general cargo is also growing, mainly through the widespread use of containers. A particularly large growth in cargo throughput has taken place in seaports of developing countries. Maritime policy aims at improving the efficiency of sea transport in Europe and the world, while ensuring its long-term competitiveness. This can be achieved by the dissemination of technologies leading to increased productivity, minimizing negative environmental impacts and creating conditions for effective operations and integration of ports in transport chains.

8

Authors: Michael OELJEKLAUS, Lubomír PEŠÍK

The subject of this paper is the design of a control system for slow running bearings including a strength analysis and load capacity measurement. The intention here is to apply the results to the manufacturing operation of chain conveyors in paint shops.

9

Authors: Firas ALRAWI

This research is an attempt to compare engineering solutions for traffic intersections from a planning viewpoint. In this research, various solutions have been discussed for traffic intersections (traffic light, roundabout, underpass and overpass). The research highlighted the importance of each of these solutions in urban environments and clarified all variables related to the pros, cons, costs, capacity and environmental compatibility of each of these solutions with the surrounding urban environment. Weights were developed for all these variables, then correlation was determined using the linear regression method. The analysis of statistical results shows that the creation of underpasses often achieves most of the designated goals when compared to other solutions, despite some technical difficulties and high construction costs.

9

Authors: Elżbieta MACIOSZEK, Damian LACH

General traffic measurements are carried out to determine basic traffic characteristics on voivodeship roads and national roads. The basic measure obtained during these measurements is annual average daily traffic. This is the number of vehicles that have passed over a specified point of a road section within a 24-h period on average within one year. For voivodeship roads, average daily traffic, average daily evening traffic and average daily night traffic are also determined. In the case of national roads, average daily summer traffic and average daily winter traffic are determined. The article presents a comparison of the characteristics for national roads in the Silesian Voivodeship and for national roads in Poland in the period 2000-2015.

10

Authors: Marcin ŁOPUSZYŃSKI, Izabela PENDZICH

The article presents the results of a pilot survey conducted among public transport drivers, including of buses and trolleybuses, in three cities in Poland. The research was aimed at checking the existence of the need for advance notice systems concerning traffic light signal changes. This issue was examined using information on these drivers’ vehicles from countdown timers and traffic lights other than those for the lane in which the vehicles were moving. The respondents also indicated their proposals for advance notice systems for traffic light signal changes.

11

Authors: Agata KUREK, Jakub JUŻYNIEC, Bartosz KIELC

The article discusses the level of road safety in the case of the city of Sosnowiec. Traffic safety was compared over a 11-year period from 2006 to 2016. The data were obtained from the municipal police headquarters in Sosnowiec. The authors of this publication created a graphical presentation of traffic incidents with their participants and causes. Numerical data have been presented, and separated into road accidents and collisions as well as injured and fatalities. The age and sex characteristics of the perpetrators of road accidents were presented. The QGIS program was also used for the analysis, which allowed us to map the most dangerous intersections in Sosnowiec.

11

Authors: Aleksander SOBOTA, Grzegorz KAROŃ, Renata ŻOCHOWSKA, Marcin Jacek KŁOS

The article is a presentation of the authors‘ research work on determining the impact of countdown timers on traffic conditions, and - in this case - on the level of traffic safety at intersections. Therefore, the scientific aim of the article is to present the methodology used by the authors to carry out research in order to determine the influence of the function of the intersection with countdown timers within an urban transportation network on the level of safety at the intersection. To achieve the scientific objectives, measurements of traffic at three intersections with different functions in a transportation network have been performed.

13

Authors: Zbigniew ŁUKASIK, Aldona KUŚMIŃSKA-FIJAŁKOWSKA, Sylwia OLSZAŃSKA

The escalating globalization of the market, increased competitiveness and the necessity to intensify actions directed at an appropriate level of logistics customer service, as well as the growth in provided services, are the most important strategic decisions made by transport enterprises. The tendency of transport enterprises to ensure fluidity of supplies and reduce the costs of transport processes requires the use of innovative technologies, which allow companies to improve the control of transport services. Enterprises plan transport services to minimize the costs. Therefore, looking for and implementing new solutions, which have an impact on increasing the efficiency of transport processes, are driving forces for every transport company. In this article, the authors conducted an analysis of the process of providing transport services in a specific enterprise. The authors also show that transport processes may be improved through the implementation of innovative monitoring system

15

Authors: Leszek MINDUR, Grzegorz SZYSZKA

The article addresses the overall body of problems pertaining to economic factors conditioning the construction and operation of integrated logistics centres (ILCs). These problems are among the most fundamental decision-making dilemmas related to such investments. The authors of the article have discussed the methodology of assessment and selection of economic factors for the cost-effective construction and operation of ILCs by taking the perspective of entities involved in the construction and functioning of these centres into consideration. Model ILCs are understood as facilities of a specific spatial and functional nature, along with all the infrastructure and organization, where logistics services are rendered in the scope of receipt, storage, distribution and release of goods, supported by auxiliary services provided by businesses independent of forwarders or recipients[3]. From the perspective assumed in the article, logistics centres are considered as projects implemented by both privately owned and public entities, which are open to participation with different economic entities representing the ILC sector, as well as other industries performing their logistics operations on the centre’s premises and using its infrastructure. The article draws from the authors’ own experience, research and insights.

24

Authors: Ali KEYVANFAR, Arezou SHAFAGHAT, Hasanuddin LAMIT

Growing concern about transportation emissions and energy security has persuaded urban professionals and practitioners to pursue non-motorized urban development. They need an assessment tool to measure the association between the built environment and pedestrians’ walking behaviour more accurately. This research has developed a new assessment tool called the Walkable Integrated Neighbourhood Design (WIND) support tool, which interprets the built environment’s qualitative variables and pedestrians’ perceptual qualities in relation to quantifiable variables. The WIND tool captures and forecasts pedestrians’ mind mapping, as well as sequential decision-making during walking, and then analyses the path walkability through a decision-tree- making (DTM) algorithm on both the segment scale and the neighbourhood scale. The WIND tool measures walkability by variables clustered into five features, 11 criteria and 92 subcriteria. The mind-mapping analysis is presented in the form of a ‘Walkability_DTM-Mind-mapping sheet’ for each destination and the overall neighbourhood. The WIND tool is applicable to any neighbourhood cases, although it was applied to the Taman Universiti neighbourhood in Malaysia. The tool’s outputs aid urban designers to imply adaptability between the neighbourhood environment and residents’ perceptions, preferences and needs.

7

Authors: Agnieszka FORTOŃSKA

The author of this article will discuss issues related to aircraft accidents. The paper will set out the investigative activities carried out by Poland’s State Commission on Aircraft Accidents Investigation. The author will also address the concept of liability for aircraft accidents. The paper will be concluded with comments on aviation accidents.

9

Authors: Grzegorz BUDZIK, Aleksander MAZURKOW

The paper presents modelling process and results of the bench tests of the C0-45, which is a turbocharger for heavy-duty diesel engines. For turbochargers like this, it is necessary to measure the level of vibration. This paper presents the test results for 115 turbochargers. Rotor speed during the tests varied between 25,000 and 42,000 rpm. Rotor speed during the tests on a C0-45 turbocharger varied within three ranges, i.e., Range I: n=25,000-32,000 rpm and a=0.5g; Range II: n=33,000-38,000 rpm and a=1.0g; Range III: n=39,000-42,000 rpm and a=1.5g; (g=9.81m/s2). Measurement of vibrations was realized by a sensor located on the body of the turbocharger. Bench tests also included measurement of key charge parameters such as the amount of mass trapped, mean flow velocities, turbulence level, gas pressure, temperature and oil flow. The results are presented in the form of diagrams showing the amplitude of the acceleration function with regard to the rotor’s RPM. Research shows that using the correct parameters in construction and technological processes of assembly are very important for the effective functioning turbochargers.

9

Authors: Bożena SZCZUCKA-LASOTA

This paper describes the influence of road transport on urbanization and the transport of oversized loads. There is an increasing interest in oversized transport and urban development. In this developmental context, it is necessary to transport heavy construction machinery, infrastructure elements, pipes for gas pipelines and waterworks, or even rails to create roads for rail transport. For this purpose, the transport of loads exceeding standard parameters (16.50 m in length, 2.55 m in width, 4.00 m in height and 40 Mg in mass) is used. Oversized traffic has many obstacles on the roads, such as low bridges and viaducts, narrow roads, poor technical condition of roads, road works and low-permeability roundabouts.

11

Authors: Marek BISTÁK, František BRUMERČÍK, Michal LUKÁČ

This article presents a brief overview of weighing systems and devices designed to facilitate fluent and safe road traffic. The number of vehicles on roads is perpetually on the rise, resulting in increased wear of road surfaces. This is why weight check gates have widely been implemented to check the speed and weight of a vehicle against what is permitted by law. A cheaper, albeit more time-consuming, traffic weighing alternative would involve weighing points using weighbridges or mobile axle scales. The second part of this article examines the development of an axle scale. The design and calculation works were performed with the use of the Creo Parametric CAD system and the ANSYS Workbench FEM system.

11

Authors: Jerzy MARGIELEWICZ, Damian GĄSKA, Grzegorz WOJNAR

This paper presents the results of computer simulations of a gear model, where the variable stiffness of the meshing and backlash are considered. The outcome of such assumptions is a non-linear mathematical model in which chaotic phenomena can occur. During model studies, attention was paid to the identification of areas limited by the physical parameters, for which the analysed system behaved chaotically. To determine the ranges of irregular gear behaviour, numerical procedures were used to plot the bifurcation diagram, the Lyapunov exponent, the amplitude-frequency distribution and the Poincaré cross section.

12

Authors: Kamil KRASUSKI, Janusz ĆWIKLAK

The aim of this article is to present the results of GLONASS positioning in kinematic mode in air navigation. The flight experiment was conducted at Dęblin Airfield on a Cessna 172 aircraft. The aircraft position was recovered on the basis of the single-point positioning (SPP) method of the GLONASS code observations. The numerical computations of aircraft coordinates were executed in the RTKPOST library of the RTKLIB software. The standard deviations in aircraft position in a BLh geodetic frame were checked with the ICAO standards on civil aviation for the GLONASS system. The typical accuracy of aircraft positioning on the horizontal plane is better than 12 m, whereas, on a vertical plane, it is better than 17 m. In this paper, standard.

12

Authors: Elżbieta MACIOSZEK, Damian LACH

Tools for counting traffic are not only used to obtain information about traffic conditions and necessary data in order to design new transport system infrastructure. They primarily allow for the assessment of road users’ communication needs, as well as their dynamic mobility in the transport network of the analysis area. In these aspects, general traffic measurements (GTM), which, since 1965, have been performed in Poland every five years, are extremely helpful. The article presents the results of a detailed analysis of the data derived from the GTM conducted in the period 2005-2015 on voivodeship roads. The analysis was carried out using results from the West Pomeranian Voivodeship.

13

Authors: Damian TOBÓR, Jacek BARCIK, Piotr CZECH

Over the past few years, interest in the use of unmanned aerial vehicles (commonly referred to as drones) has increased. Uncontrolled drone flights poses a threat to air navigation, including air transport. The aim of this article is to identify potential sources of this threat, together with the identification of Polish legal regulations that respond to them. Conclusions will be based on proposals de lege ferenda, i.e., related to the postulated change of legal regulations, in order to limit the risk of incidents. The object of the article is subordinate to its structure, consisting of five parts. In the first part, the concept of unmanned aerial vehicles used by the Polish legislature will be defined, which is necessary because of the inaccuracies surrounding it. The second part will present ways to use drones for civilian purposes. The next part of the article will describe the cases of accident and aerial incidents involving drones. The fourth part focuses on the indication of Polish legal regulations related to the exploitation of drones. The article closes with concise conclusions.

14

Authors: Serhiy MELNYCHUK, Ivan VITIUK, Ihor BOVSUNIVSKYI, Dmytro BEHERSKYI, Yuriy KUBRAK

An N1 vehicle model is created, which allows for changing suspension parameters and conditions of experimental performance. A methodology of computer testing performance for vehicle ride comfort and stability service properties’ characterization in a virtual environment is proposed. Vehicle suspension system modelling and simulation are performed. The results of the N1 vehicle suspension system from full-scale laboratory and road tests are given.