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The prediction of delays and their reduction in all modes of passenger transportation, especially rail transportation, is of great importance and annually attracts the attention of many researchers. Train delays can be anticipated by predicting the arrival times of trains at stations. In this paper, a train operated by Raja Company, which travels daily on the Tehran-Mashhad route, has been investigated. This train route consists of 50 stations, of which five main stations, including Tehran, Garmsar, Semnan, Shahrud, and Mashhad, have been selected to predict the train's arrival and departure times at each of these stations. For this purpose, data related to the train timetable and the operations carried out at these five main stations over three years from 2018 to 2020 have been collected. Then, modeling was conducted to predict real-time arrival and departure times for each of these stations. Artificial neural networks, random forest regression, gradient boosting regression, and extreme gradient boosting regression were used for prediction modeling. After evaluating these models, the approach that yielded the best results based on the experimental data was selected for predicting the arrival and departure times at each station.

This paper aims at to improve the vibration behavior of the train floor panel by the use of a cellular auxetic layer. A field measurement is performed to obtain the vibrational frequency content of the body floor moving on the tangent track. Using acceleration sensors, the vibrational response is measured on the bogie (as the input excitation) and on the floor panel (as the observation response). Finite Element modeling for the floor panel is accomplished and measurement data are used for both the input excitation and the verification of the numerical results. The floor panel is a sandwich panel containing multiple layers. In this study, the conventional wooden layer of the panel is substituted with a cellular auxetic one with a re-entrant hexagonal pattern. Then, an optimization problem is defined while the topological parameters of the auxetic layer are the design variables and the dynamic performance of the panel is the objective function. The parameter of power–mass–ratio (PMR) is defined taking the effects of both weight and dynamic response amplitude into calculation. It is found that the PMR is reduced to almost 0.6 by replacing the wooden layer with an auxetic one, and after topological optimization, it is reduced to 0.35. [ABSTRACT FROM AUTHOR]

Under the background of network conditions, the generation and optimization of intercity railway train operation scheme is a huge system engineering with many factors involved and its complexity changes exponentially. In order to quickly generate and optimize intercity railway train operation scheme under network conditions, the concept of node importance is combined with the generation and optimization of intercity railway train operation scheme. A optimization model of intercity railway train operation scheme is established to maximize the benefit of railway transportation enterprises and the proportion of direct passenger flow, and minimize the total travel cost of passengers. In the meantime, as the multi-objective and multi-constraint programming problem is difficult to be solved directly, the hierarchical solution method is used to generate the optimal scheme. Results show that the method can simplify the generation and optimization of the operation scheme, the optimal scheme is in good agreement with the actual operation diagram, the hierarchical solution method can generate the optimal scheme within a relatively short iteration period with improved efficiency, and it can provide reference for improving the efficiency of intercity railway train operation scheme and effectively guide the design of passenger transport organization under network conditions [ABSTRACT FROM AUTHOR]

Fire safety is an important research area in the rail transportation system. In the event of an emergency, it is important to evacuate railway vehicle in a safe and appropriate manner to minimise injuries and reduce fatalities. Rail companies traditionally conduct fullscale tests. These tests present several drawbacks such as their unrealistic results and their cost-effectiveness. This has led to the necessity of innovating approaches for fire safety training. In this context, new technologies have been employed for evacuation training such as virtual reality (VR). The purpose of this article is to highlight the state of the art of VR simulation of train fire evacuation and examine how VR studies complement conventional research approaches such as drills, laboratory tests and computational models. The findings reveal that VR technologies have great potential for serving as a promising complementary laboratory tool to improve fire safety. Finally, the necessity of new VR researches on passenger train fire evacuation is addressed. [ABSTRACT FROM AUTHOR]

To improve the passive safety protection of crash energy management (CEM) passenger train, this paper presents the energy absorption design study for CEM passenger trains based on a 1/8th-scale model. By analysing the similarity of thin-walled structures for CEM trains, the similitude ratios of physical parameters were obtained and used to design the scaled train model. The dynamic responses of scaled train were analysed through finite element simulation and collision test. Compared to the test results, the errors of dynamic responses in simulation were within 1.79%, indicating that the finite element model of scaled train was accurate and can be used to study the energy absorption characteristics of CEM passenger trains. To improve the crashworthiness of CEM passenger trains, selecting six key parameters affecting energy absorption of head car and middle car as design variables, and taking the maximum energy absorption of head car and the minimum standard deviation of energy absorption for middle cars as targets, a multi-objective optimization was carried out to gain the optimal solution of key energy absorption parameters. Optimization results indicated that the energy absorption of head car has been increased by 195.20%, and the standard deviation of the energy absorption of middle cars has been decreased by 81.06%. [ABSTRACT FROM AUTHOR]

Sand and gravel blown up by strong wind will cause damage to windows. Following up, it will cause the change in the flow field around a train immediately, which has a significant impact on the aerodynamic performance of the train. Delayed detached-eddy simulation based on the shear stress transport κ-ω turbulence model was used to investigate the aerodynamic characteristics of passenger vehicles under crosswind, and the effect of damaged windows on the train aerodynamic performance and flow field around the train was analyzed and compared. The grid generation and numerical method are verified in the previous studies. Results show that the aerodynamic performance of a passenger vehicle is significantly affected by damaged windows on both sides of the passenger vehicle, both the aerodynamic lateral force and overturning moment of the passenger vehicle were decreased, and this has a small effect on the aerodynamic performance of the downstream passenger vehicle. Fluctuation of the aerodynamic lift, lateral force, and overturning moment of a vehicle with damaged windows on both sides of the vehicle is significantly increased. Damaged windows do not change the existence of the main vortices around vehicles, but the size, location, and strength of the main vortices are obviously changed, especially when windows on both sides of the vehicle are damaged. Therefore, when windows on the windward side of the vehicles are damaged, opening or broking windows on the leeward side of the vehicles will help reduce the risk of vehicles overturning and derailment. [ABSTRACT FROM AUTHOR]

The article presents a new approach to control of train movement based on a combination of terminal (finite) and fuzzy control methods using a logical-linguistic model whose numerical parameters are determined on the basis of search optimization and simulation modeling. The results of computational experiments are presented and given recommendations to the application and further development of the proposed approach. In particular, the proposed logicallinguistic model can be used in the construction of on-board systems of suburban electric trains. [ABSTRACT FROM AUTHOR]

The article presents a new approach to control of train movement based on a combination of terminal (finite) and fuzzy control methods using a logical-linguistic model whose numerical parameters are determined on the basis of search optimization and simulation modeling. The results of computational experiments are presented and given recommendations to the application and further development of the proposed approach. In particular, the proposed logicallinguistic model can be used in the construction of on-board systems of suburban electric trains.

Each year around the world there are still several cases of train derailments on the curved tracks due to overspeed, leading to big casualties and costs to the rail industries. With the ongoing increase on the speed, the possibility of train derailment will increase, especially on the sharp curved tracks. Two guard rails (or check rails) are usually required to be placed inside and parallel to two running rails along restrictive clearance areas of the bridge, tunnel, and turnout, preventing the rail vehicle wheels from turning over the rails in case of derailment. However, the investigation on the guide rail which is used to mitigate the train derailment due to a curved track and overspeed is carried out in this paper through the simulations. On sharp curved tracks, one guard rail can be placed inside the low rail, where it engages the back of the wheel flange. The simulations demonstrate that the guard rail can reduce the train derailment potential caused by a sharp curve and overspeed. The lateral clearance between wheel rim back and guard rail, as well as the height over the low rail top, is crucial in the effectiveness of guard rail. Their optimal selections could be obtained through the further simulations.

Purpose. The development of high-speed railway traffic requires the updating of requirements for the design of passenger rolling stock and revision of safety standards on emergency situation of trains with an obstacle. To the construction crews of the new generation demands by equipping them with passive crash systems, ensuring the safety of passengers and personnel in an emergency situation. In order to refine test scenarios train collision with an obstacle and evaluation indicators of energy absorption of the collision of the passive protection devices which are used in computer modeling. The first step in the research of dynamic processes in the train when excessive shock effects, is to assess the maximum values of the compressive forces generated in intercar compound trains, locomotive and cars which are equipped with passive safety systems.Methodology. Based on the concept of passive protection of passenger rolling stock for track with width of 1520 mm on emergency situation the conceptual passive safety system for passenger trains with locomotive traction are formed from the crews of the new generation was proposed. The passive safety system is recommended to be equipped both the locomotive and cars. For a preliminary assessment of compliance for the passive safety system of a passenger train on emergency situation, as a rule, the simplified discrete-mass model is used, in which the train is considered as one-dimensional chain of rigid bodies connected by nonlinear deformable elements. Findings. The algorithm for computing efforts in the inter-connections of the train locomotive traction of the permanent formation is developed, taking into account the specifics of work of coupling devices, devices, energy absorption and elastic-plastic properties of the body structure of crews at emergency situation. Originality. The proposed algorithm allows taking into account the peculiarities of train locomotives of the new generation and the work of the inter-connections in the study of dynamic processes in train in case of emergency situation with an obstacle on the railway track. Practical value. Developed algorithms for computing the efforts of the interaction of the crews of passenger trains with locomotive traction, equipped with passive safety systems that can be used in mathematical modeling of test reference collision scenarios of trains with obstacles for improvement of passive safety systems in the design phase of the passenger rolling stock of new generation.