The paper aims to propose a method of reconfiguring the train timetable, taking into account minimising the globally consumed energy for traction purposes. This is a very important issue in the context of rising electricity prices, alarming climate changes and the “Fit for 55” policy introduced in Europe. Each unit of energy saved contributes to improving the state of the planet and reducing the negative human impact on it. In this paper, the authors propose a model that, when applied, will reconfigure the timetable in terms of energy intensity and, as a result, reduce the impact of railways on the burden on the environment. It is proposed to introduce an interdependence between trajectories of electrical train movement. This interdependence is to take place so that it is possible to efficiently transfer the energy recovered during the braking of one train to another train, moving on the same section of the railway line and at the same time (i.e., without using energy storage devices). The paper provides a physical background to the considerations—discussing the movement of electric trains in the context of their energy intensity and the possibility of energy recovery; presenting the possibility of interconnecting trains in such a way that the energy from a train that is being braked can be efficiently used by a train that is being accelerated; presenting a method for making the linkages between trains (in the form of an original algorithm resulting from the application of the Delphi method) and implementing them in the timetable. The timetable for the application of the method is real and was obtained from the railway operator in Poland, as a mathematical–physical model describing the trajectory and energy consumption of the original, after which the proposed timetable was verified by running simulations and comparing the energy consumption of the original and the proposed timetable. It turned out that it is possible to achieve a global total energy demand reduction of up to 398 MWh/year. This proves the validity of using the proposed algorithm at the timetabling stage and extending its implementation to the entire network. Furthermore the authors also recognise the tendency of the algorithm to return repeatable solutions, which has the side effect of creating a cyclic timetable. Its implementation in Poland has proved impossible for many years. The application of the proposed method could change this unfavourable situation.

This paper presents a practical method for managing an airport security control system. The proposed management system considers the influence of the operation of the check-in system on the stream of passengers reporting for security checks, which has so far been neglected. In this work, the check-in and security control systems were analysed separately. Accounting for this relationship allowed significant savings in work hours (and therefore reduction of costs) while maintaining the desired efficiency of the system (no queues). The method is based on seven steps. The first two steps address a method for estimating the relationship between the number of passengers entering the check-in system and the number of passengers entering the security control system. A confidence interval is determined for the aforementioned relationship. The following steps provide a method for determining the parameters of the security control system, including the probability density function (PDF) of the security control lane capacity, the hierarchy of security control lanes and the PDF of the security control system capacity. Step 6 provides methods for determining the expected stream of passengers leaving the check-in system and the final step provides an algorithm for determining the number of open security checkpoints.