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This study publishes results of tests with regard to determination of the aircraft positioning accuracy by means of the GPS navigation in aviation. The research exploits the mathematical model of the linear combination "IonosphereFree" in order to designate the coordinates of an aircraft. The research uses the actual GPS code observations, recorded by a satellite receiver mounted in the Cessna 172, at the time of the experiment for the EPDE military aerodrome in Dęblin. The computations of the position of the Cessna 172 aircraft for the linear combination "Ionosphere-Free" were made in the APS Toolbox v.1.0.0. programme. Within evaluation of accuracy of the GPS positioning in aviation, the determined coordinates of the aircraft Cessna 172 from the APS programme were compared to an accurate reference position from the solution derived by the PPP measurement technique. In the research, the authors obtained an average positioning accuracy of approximately 5 m in the geocentric XYZ coordinates and approximately 4 m in the ellipsoidal BLh coordinates. In addition, the 3D-error parameter is lower than 7 m for the XYZ geocentric coordinates.

The electric parking brake (EPB) system as the complex mechatronic system consists of the actuators that generate the clamping force necessary to hold the vehicle safe, the conventional calipers that convert clamp force into brake torque, electronic hardware with the Electronic Control Unit (ECU), cable harness and switches and especially the control software providing the functions that the driver will experience. Like most of the modern automotive components, the EPB is equipped with embedded electronic systems that include ECU, electronic sensors, signals, bus systems, and coding. Due to the complex application in electrical, electronics and programmable electronics, the need to carry out detailed safety analyses that are focused on the potential risk of malfunction is crucial for automotive systems. This paper describes a possible division of the EPB sub-functions between the supplier the wheel brakes and the supplier which supplying the ECU. Functional safety must be a guarantee with concerning the overall vehicle system. Functional safety is according to the requirements of the ISO 26262 standard and in the context of this paper relates solely to the E/E components (electrical and/or electronic) of the EPB. This paper covers the hazard analysis and risk assessment relevant to the EPB control software, and the derived allocation of ASIL risk levels to the EPB software elements of the functional architecture of the EPB.

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.

Paper presents diagnostic analysis of automotive ignition system for various working and adverse conditions in laboratory. Description and importance of basic diagnostics of automotive ignition system are examined in the first part of the paper. In the second the focus is placed on the basic principles and solution of the spark plug model. The test laboratory device is proposed in the following and the specialized measurements were executed by the proposed measurement system. The faults were simulated by application of oil and gasoline between the electrodes and failing by the driver to make the ignition contact on the spark plug.

The article presents and describes research results concerning determination of an impact of the ionospheric correction upon the positioning accuracy of an aircraft. The main objective of examinations was to verify three ionospheric models (the Klobuchar model, SBAS model and IONEX model) in determining aircraft coordinates. In the framework of the conducted simulations, the authors determined the aircraft coordinates by means of the SPP code method in the GPS system. The article presents a comparison of the determined aircraft coordinates in the SPP code method in relation to an accurate solution in the RTK-OTF differential technique. Based on the obtained results, it was found that e use of the SBAS and IONEX model is exploited to improve the positioning accuracy of an aircraft in relation to the Klobuchar model, from 20% to 72%, in the geocentric XYZ frame. The obtained findings of a simulation indicate that the ionospheric correction in the SBAS and IONEX models may be used to improve the performance of aircraft coordinates in air navigation.

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.

The Friction stir welding (FSW) is a complex process, depending on many factors: machine, clamping device, material and tools. Parameters that have a direct impact on the quality of the joint include the rotational speed, welding speed, clamping force, geometry and tool plunging depth. The paper presents the results of experimental studies concerning the effect of tool pin length on the microstructure and mechanical strength of joints of thin sheets made of Al 7075 alloy. A tool with an adjustable pin with concave shoulder was used to weld the joints. Different pin lengths were used, which were selected with respect to the thickness of the welded joint. The specimens were subjected to visual evaluation, metallographic tests and mechanical strength testing. The results indicate that the pin length has a decisive effect on the microstructural changes in the joint and thus influencing the strength of the FSW joints.

This paper presents results of research concerning determination of the GPS reference station coordinates located on the grounds of an EPDE airport in Deblin. The study uses a mathematical model of the PPP measurement technique in order to determine the coordinates of the reference station using the real GPS code-phase observations. The computations of the coordinates of the GPS reference station were carried out in numerical applications CSRS-PPP, APPS and GAPS. In this research was found that the accuracy of finding solutions to the XYZ geocentric coordinates of the reference station REF1 between solutions CSRS-PPP, APPS and GAPS ranges from 0.01m to 0.13m. In addition, the accuracy of determining the XYZ geocentric coordinates from the PPP method related to the GPS differential solution ranged from 0.01m to 0.11m.

The rapid development of transport, the widespread introduction of modern transport technologies, close cooperation with Russia, China and other neighboring countries, will allow Kazakhstan to become a serious player in the transportation market between Europe and Asia in the coming years. Such existing transport potential directly affects the economic growth of the country which will lead to high living standard. The global movement towards digitalization is transforming the logistics industry, as well. The "digit" changes the channels of movement of goods, delivery formats and management processes. Development of e - commerce and the increasing supply requirements - multichannel, responsiveness, transparency, accuracy - stimulate retailers and logistics operators to increase efficiency of processes and introduce new technologies. Therefore, the ways of prosperity of Kazakhstani economy, through digitalization of logistics processes is considered in this article.

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.

In this article, the simulation testbed of the new designed model for cooperation between QoS and security is introduced. The field of research about QoS and security provide dynamically developed and important areas of the research and up to now no protocol or mechanisms have been designed to this process. The cooperation is based on using a Cross Layer Design model (CLD) and modified Security Service Vector (SSV). A main idea of testbed is the indication how could security and QoS be integrated as a parameter to the MANET via this model. We also show how this model can affect the functionalities of the whole MANET.

This article deals with replacement of the magnetic grippers on the VPO-3-3000 machines with roller grippers. The novelty lies in establishment of dependences characterizing stress and strain in elements of the lifting and straightening devices and in rails during the operation. Reliability of the program for calculating the structural parameters of the lifting and straightening device for the VPO-3-3000 track renewal machine is shown. The developed design of the lifting and straightening device makes it possible to select the rational parameters of technology and the operating mode of the device. This design is recommended for use when developing working bodies for the straightening machines. The article presents calculation of the lifting and straightening device structural elements' strength during operation, in the Ansys WB software package.

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.

Since the entry into force of the Paris Agreement in 2015, and with the publication of the Intergovernmental Panel on Climate Change report on the consequences of 1.5 degrees of global warming, the issue of reducing greenhouse gas emissions in a cost-effective manner and within the timeframe outlined has become a matter of urgency. The transport sector, which accounts for a quarter of total GHG (Greenhouse Gas) emissions in the 28 EU Member States, is no exception. Due to the serious environmental impacts of transport, new mobility concepts are being implemented at both national and international levels. One of these is the large-scale deployment of electric vehicles, including those powered exclusively by Battery Electric Vehicle (BEV) batteries. They are quiet and virtually emission-free and, in terms of safety, have the feature that, in the event of an accident, they reduce the risk of detonating the vehicle and of burning or burning out the passengers. This article presents the current state of electromobility in Poland and Slovakia with an indication of light electric cars BEV and the most important factors stimulating its development.

Digital radiography (DR) is a powerful technique that can be used in non-destructive testing for identification of internal or external defects and corrosion mapping. New generation of digital flat panel detectors become more and more competitive to film detectors, however the transition from film to digital radiography is not always the best choice for every NDT organization especially from the point of view of investments. The paper introduces the application of digital corrosive radiography mapping on gas pipelines using a portable flat panel detector. The experimental part is focused on determining the residual thickness of the pipelines in service.

The paper deals with intermodal transportation, broadly defined as a chain consisting of several transportation modes that are coordinated and interact in intermodal terminals to ensure door-to-door service. The goal of the article is to describe the road-sea intermodal flow, to define the responsibilities of each party of a transportation chain and to identify important issues and bottlenecks in the whole intermodal transportation. Recently, the demand for the transportation of dangerous goods has been rising. Transport of dangerous goods can have serious effects on the environment if an accident happens. The legal environment for each transport department, harmonisation of the rules and regulations for intermodal transportation and setting the responsibilities for every party of the transportation chain (such as forwarder, hauler, shipper and consignor) make the transports of dangerous goods more safe and efficient and can reduce risks and threats.

There are many different views on perceived benefits and costs of the offered transport services in the market, because each customer gives a different weight to characteristics of these services. The customer thus buys a service from the transport company that offers the highest perceived benefits in relation to the total cost. Therefore it is important to monitor traffic flows of passengers in a long-distance rail passenger transport and in advance specify the expected number of passengers who use this link. Only on the basis of a well-prepared prediction it will be possible to establish an effective session tariff, which ensures reimbursement of all costs to the carrier and also guarantees a reasonable profit. The aim of this paper is to provide a cost analysis of a carrier in passenger rail transport at the risk of unoccupied capacity of a selected train in different variants of its workload and the proposal of a session tariff with respect to this risk.

A conflict is an infringement of minimum separation between at least two aircraft. Air traffic controllers build a protected area in front of an aircraft; its shapes and dimensions depend on the speed of an aircraft and on the minimum separation. The protected zone in this mathematical model is the horizontal rectangular zone. If an aircraft is inside this protected zone, a conflict occurs. The model is based on these assumptions: aircraft fly in level straight line routes; only an infringement of the lateral separation is considered; deviations are excluded; aircraft at the same flight level fly at the same average speed; aircraft fly towards an intersection and change direction after the intersection. Hence, conflicts mainly occur owing to the loss of minimum separation between aircraft flying at the same flight level. The calculation of average number of potential conflicts is designed for a long time interval; hence, aircraft velocity deviations are negligible. The mathematical model in this paper is intended to compare different alternative intersection configurations of air traffic service routes. The comparison is based on the following results: an average number of potential conflicts per hour at route intersections, index of conflict intensity, and intersection capacity.

Digital video broadcasting (DVB) transmission technologies are suitable for wireless delivery of multimedia content both to static and mobile end-users. On the one hand, DVB-T standard has been adopted for digital terrestrial television (DTT) and it has been further developed into a newer standard, DVB-T2, which was recently finalized. On the other hand, DVB-H is a specification for the transmission of digital TV to handheld user terminals such as smart phones delivering IP-encapsulated data. The combination of satellite and terrestrial DVB technologies is DVB-SH which delivers wide coverage to mobile terminals and promises upgraded services to mobile and vehicle users via a satellite link. The objective of our research article is to present a survey on terrestrial, mobile and hybrid DVB multimedia networks. Emphasis will be given on quality of radio and service related aspects. A focus on performance evaluation methodology based mainly on measurement campaign will be proposed with a detailed presentation of experimental equipment for drive-test field measurements. Guidelines of measurements and analysis processes will be described. A public DVB network in the area of Athens will be our case study.

The costs of each company on the market are an essential component of financial decision making, not only on the price of the goods and services provided, but also about the business efficiency. In business, services have a significant impact on pricing, but also for deciding on the realization of performances. Costs structure is composed of fixed and variable costs. Changing the costs structure creates assumptions for other decisions, as well as the pricing of the entrepreneur. The goal of this article was to identify, whether there is a change in time of the costs structure.

It was established that the polymeric component of the organomineral modifying complex changes the nature of the super-molecular structures in the activated cement system - at optimal filling, globules decrease in size preventing the phase surface diffusion, which contributes to increase of the waterproofness of modified concrete. When introducing a modified cement system into the concrete mixture, the reduction of the open porosity to 3-5%, depending on the composition, has been achieved. Conducted tests for water resistance and frost resistance of the repair layer of concrete showed that the modified concrete corresponds to the mark on water resistance W14 and the brand on the frost resistance F300. The developed technology of physico-chemical activation of the cement system allows the use of conventional cement for obtaining durable concrete of special purpose, which allows to reduce the cost of such concrete by 27-34%.

For many years issues of the free provision of transport services, including urban public transport, were outside the main trends of transport economics considerations. However, nowadays, the discussion is ongoing related to usefulness and limitations of the free urban public transport implementation. Protection of the city environment, reduction of personal cars traffic, and increased accessibility and mobility in cities are given as premises for such solution introduction. However, assessments of introduced solutions may not necessarily confirm the assumptions made. Financial problems and those in provision of services - characteristic of goods and services provided for free - add to that. The paper has undertaken the issue related to premises and limitations related to introduction of the fare free urban public transport in regard to the pursuit of effectiveness in the public management.

The aim of this paper is to compare economic and operational aspects in the transition from direct road transport to unaccompanied CT using intermodal road semitrailers. A comparison of specifications of transport units was carried out as well as the risk assessment, considering the probability of a critical situation occurrence. Both of these factors are key for the final decision making. As a main part of this research paper, a comparative case study was conducted. For the purposes of this comparison, data from actual transport orders were used on a route starting in the Czech Republic, going through the industrial Northwest of Germany and then to Belgium and the Netherlands. As a result of this research, the direct cost of road transport and CT were compared considering the lifespan of the used equipment. Besides that, the investment cost for a road carrier to enter the CT system was quantified, which is essential for the CT system development.

The article elaborates on measures aimed at increasing the performance of the rail freight transport carried out in the north-south direction. The measures are designed based on the implemented analyses focused on the analysis of the current situation of international trade and development of international transport as well as the analysis of the current situation of the European transport infrastructure. The north-south direction was selected due to the enormous increase of the transit road transportation.

A machine learning approach for the recent detection of crossing faults is presented in the paper. The basis for the research are the data of the axle box inertial measurements on operational trains with the system ESAH-F. Within the machine learning approach the signal processing methods, as well as data reduction classification methods, are used. The wavelet analysis is applied to detect the spectral features at measured signals. The simple filter approach and sequential feature selection is used to find the most significant features and train the classification model. The validation and error estimates are presented and its relation to the number of selected features is analysed, as well.

The aim of this paper was to define the important market risk sources in the transport small and medium-sized enterprises segment. A part of this aim is to find out how entrepreneurs evaluate these sources, and quantify the differences in their evaluation based on the entrepreneur's characteristics, such as nationality, age, gender and others. The questionnaire was completed by 122 enterprises from Slovakia, Poland, the Czech Republic and Serbia. Statistical tools such as pivot tables, percentages and goodness-of-fit tests were applied to verify the formulated hypotheses. The most important source of market risk is a strong competition in the line of business. The obtained education of entrepreneurs is statistically significant characteristics for the evaluation of the market risk sources in selected transport enterprises. The findings are important for state institutions and their support systems in the transport SMEs segment.

This paper presents the draft methodology to be applied for evaluating the financial health of airlines. In the introductory part, specific attributes, regarding the individual types of airlines, are described. Subsequent parts of the manuscript outline advantages and disadvantages to measure airlines performance when implementing financial indicators, as well as a general procedure to evaluate the financial situation of a company operating in the aviation industry. The most important part of the paper includes the proposal of the specific functional system to evaluate the economic performance of airlines. Financial evaluation itself (evaluation of financial indicators of the enterprise's economic performance) is performed through a particular case study when comparing several existing airlines.

The article presents and describes results of research in determination of the aircraft positioning accuracy with use of the GPS and EGNOS satellite systems in the air navigation. The article, in particular, makes a comparison of the designated aircraft coordinates in the GPS and EGNOS systems in relation to the reference position, determined from the precision differential RTK-OTF technique. The experimental test was conducted in Slovakia, in the vicinity of Kosice airport. In the test, a trial flight by Cessna aircraft was executed over the village of Bidovce (LZBD) in Slovakia, in East-Central Europe. Within the conducted investigations, the GPS and EGNOS positioning accuracies were determined in real time during an in-flight experimental test. Based on the conducted investigations, it was found that the accuracy of the GPS positioning in the air navigation equals ±10 m throughout the most part of the air test. In the same period the EGNOS positioning accuracy in air navigation is equal to ± 5 m.

Airspace domain may be represented by a time-space consisting of a three-dimensional Cartesian coordinate system and time as the fourth dimension. A coordinate system provides a scheme for locating points given its coordinates and vice versa. The choice of coordinate system is important, as it transforms data to geometric representation. Visualization of the three and more dimensional data on the two-dimensional drawing - computer monitor is usually done by projection, which often can restrict the amount of information presented at a time. Using the parallel coordinate system is one of possibilities to present multidimensional data. The aim of this article is to describe basics of parallel coordinate system and to investigate lines and their characteristics in time-space.

This study is devoted to determining the geometric, kinematic and dynamic characteristics of a vehicle. To this purpose, it is proposed to use a complex approach applying the models of deformable body mechanics for describing the oscillatory movements of a vehicle and the computer vision algorithms for processing a series of object images to determine the state parameters of a vehicle on the road. The model of the vehicle vertical oscillations is produced by means of the viscoelastic elements and the dry friction element that fully enough represent the behavior of the sprung masses. The introduced algorithms and models can be used as a part of a complex system for monitoring and controlling the road traffic. In addition, they can determine both the speed of the car and its dynamic parameters and the driving behavior of the individual drivers.