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Railway line capacity is growing in importance as a criterion for the assessment of railroad infrastructure performance. This problem is becoming more and more relevant as the demand for rail transport increases, especially considering the transport policy related to the promotion of climate-neutral means of transport. Insufficient capacity affects the stability and reliability of railway traffic operations. The analytical methods used for capacity estimation are typically insufficient to solve problems of a multicriteria nature (i.e. problems which take traffic heterogeneity and human factors into account). Optimisation methods, on the other hand, usually yield the best results if the current timetable for a given line is known. Additionally, they do not strongly consider the impact of the running characteristics of a specific train type and of the system or several systems in operation on the line (e.g. national Class B system and ERTMS/ETCS system). Therefore, this paper proposes a model and a simulation program developed in the Matlab and Simulink environment to be used to simulate on-route train movement, to study railroad capacity with different control systems, as well as for predictive train control to minimise energy losses. The authors described the assumptions adopted for the simulation program and the input parameters configurable against a specific line segment. They also discussed selected results derived from simulations of controlling the departure of trains to a railway line with the purpose of energy loss reduction.

Regeneration of parts is the most correct form of use of worn out components and contributes, among others, to reduce CO2 emissions. In the case of elements of fuel injector systems, very high precision is required and such regeneration should be carried out using the original parts. It also requires testing on the original testing stands of these manufacturers, which very often characterized by the fact that it is not possible to perform a short test, which means that it is only possible to perform a time-consuming comprehensive test. An unquestionable advantage in some cases would be the possibility of preliminary verification of the correct operation of the regenerated subassembly without the need for a full time-consuming test. In the present situation, only after completing a time-consuming comprehensive test of the diagnosed element of the injection system, it is often necessary to carry out its disassembly, replacement or correction of one of the components and reassembly with the next time-consuming test. In the case of low unemployment in the labour market, this is extremely unfavourable, and it is often not possible to organize work in such a way that the diagnostic test of the subassembly takes place without the participation of an employee. On the basis of the analyses presented in this article, carried out in the research and development department in company whose employee is one of the co-authors, it can be stated that in the current situation on the labour market where skilled workers are required to work and for the development of science is the most purposeful recognition of the possibility of using vibroacoustic signals to shorten time of tests, which with a high probability may end in a negative result. The preliminary analysis carried out, show that limitation of diagnostic time can be over 35%.

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.

This article is dedicated to the subject of gearboxes, with a specific focus on the load distribution on the tooth. The aim of the study was to review the selected solutions and methods that can contribute to aligning the load on the width of the tooth. The structure and operation of each solution are described in detail. The paper presents the possible benefits of using the described solutions.