Train Model Research Articles

Palmprint spoofing detection by using deep learning technique on Multispectral database

The protection of Biometric systems against attacks is crucial as biometric devices proliferate in the field of personal authentication. The presentation assault is the most prevalent type of attack on biometric systems; it entails presenting a fake copy (artefact) of the true biometric to the sensor in order to gain unauthorised access. The vulnerability in palmprint-based biometric systems has not received much attention despite the substantial threat posed by these assaults. In this research, we show how to detect a spoof palmprint image. Spoofing attacks involving faked images pose a significant threat to biometric systems. For the suggested method, we use the CASIA palmprint database, from which we constructed our own spoof database using printed photos. After that, we did some pre-processing to obtain the ROI image and a noise-free image for feature extraction using the SIFT approach. We use the convolution neural network for classification and the SVM for comparison. We obtained a result of 96.2% for our proposed palmprint system identification and 89% for SVM. But our main goal is to train the model for spoof detection, so we take some normal images and some spoof images for our train model and use the confusion matrix to calculate the accuracy of our model. We obtain an overall accuracy of 86% for our spoof detection by computing the confusion matrix.

On the implementation of hydraulic-interconnected-suspensions at the primary suspension stage of high-speed rail vehicles

In recent years, huge investments have been made to improve the dynamic performance of high-speed trains. Research into innovative suspension components has been part of the development of this transport system for decades. Innovative devices can allow rail vehicles to deal with the constantly increasing speed required by the global market. Among the most innovative suspension layouts proposed in railway dynamics in past years, limited attention has been given to Hydraulic Interconnected Suspensions (HIS). This layout is composed of two hydraulic cylinders with external hydraulic connections. Hydraulic Interconnected Suspensions allow promising tuning capabilities due to their ability to offer different responses based on the specific inputs given to the cylinders. This layout is rarely considered for rail vehicles, and the few previous works related to this topic considered the HIS layout to be applied at the secondary suspension stage. In this context, this paper proposes applying an HIS layout to the primary suspension stage of rail vehicles, in order to overcome the trade-offs between ride comfort, running safety and maximum car body displacement that need to be considered by bogie manufacturers when designing and optimising these mechanical systems. A nonlinear physical model of the HIS is proposed for co-simulation with a Multi-body (MB) model of a high-speed train. The improvement provided implementing an HIS at the primary suspension stage is then compared to similar enhancements that could be made when tuning and varying the standard suspension components of a bogie.

Comparative study on lateral vibration characteristics of the head and tail cars of high-speed trains under unsteady aerodynamic loadings

With the increasing speed of high-speed trains, abnormal vibrations in the tail car pose a threat to its overall stability and running safety. In this study, the aerodynamic and multibody dynamics models for 3-car and 8-car trains are established. The flow field characteristics and dynamic performance around the head and tail cars under both steady and unsteady aerodynamic loadings at a speed of 400 km/h are compared. The results reveal that the surrounding flow field exhibits highly pronounced unsteady characteristics, directly leading to a significant impact of unsteady aerodynamic loadings on the train's dynamic response. Under unsteady loadings, the lateral stability indexes, displacement, velocity, and acceleration of the tail car are all worser compared to those of the head car. Additionally, the larger oscillation amplitudes and frequencies closer to the suspension modal frequencies under unsteady aerodynamic loadings contribute to more pronounced lateral displacements and accelerations, constituting a crucial factor in the observed ‘tail swing' phenomenon for the high-speed train.

Development of New Passenger and Freight Train Load Models for Dynamic Assessment of Railway Bridges

The dynamic response of a bridge to a train crossing needs to be assessed when planning new railway bridges on tracks with a line speed above or equal 120 km/h and when recalculating existing bridges for new train configurations planned to put into operation or when increasing the locally permissible line speed. In the assessment, the model trains HSLM-A and HSLM-B need to be applied as a sequence of moving loads on two- or three-dimensional mechanical models of the bridge structure as defined in Eurocode EN 1991-2. However, these load models were developed in the 1990s while in the last 25 years many new trains have been developed and put into operation with different configurations compared to the normative model trains in terms of axle distances and axle loads. As a result, the dynamic bridge response for actually operating trains can significantly exceed the permissible values, in particular the vertical bridge acceleration. The normatively regulated model trains HSLM-A and HSLM-B are therefore no longer adequate for the dynamic assessment of railway bridges, and there is an urgent need to develop new load models for passenger and freight trains, to cover the trains currently operating on the European railway network. For the reasons mentioned above, an international consortium consisting of TU Darmstadt, KU Leuven, AIT and REVOTEC was commissioned by the German Centre for Rail Transport Research (DZSF) in 2019 to develop new dynamic passenger and freight train load models for the dynamic calculation of railway bridges. This article presents the development steps carried out, the optimization methods used herein, as well as the validation of the newly developed load models on a large set of existing railway bridges.

Numerical study of aerodynamics drag and flow characteristics of the high-speed train head design

A native design of the Indonesian high-speed train has been developed as an improvement of the previous medium-speed train model. As the design speed is proposed to be increased from 160 km/h to 250 km/h, the nose shape and nose length of the train head were modified into a sharper and longer nose. In this study, numerical simulation of computational fluid dynamics was used to investigate the aerodynamic phenomena and flow behavior around the modified train head and carbodies. The CFD simulation was used as the verification of the shape design and a tool for rapid design changes and optimization. The model configuration is three cars on a real scale by ignoring other parts like the train window and door, pantograph, and train connecting. A k-ε turbulence model was used in the simulation. From this investigation, it is found that the coefficient of drag on the model is calculated to be 0.34. Meanwhile, an experimental wind tunnel test validates the result with a coefficient drag is 0.38 or 10% divergence from the numerical method.

Study on the adaptive relationship between train nose lengths and variable-section tunnel parameters: Aiming at mitigating micro-pressure waves

Environmental problems caused by micro-pressure waves (MPWs) are increasingly prominent with increase in train speed. Considering different models of trains, which may have differences in nose lengths (Ln), and certain extreme terrains where it is unsuitable to construct the buffer hood outside the tunnel, this study numerically investigated the adaptive relationship between Ln and variable-section tunnel parameters [i.e., the length (L1) and area (S1) of the entrance expansion section] for minimizing the MPW. The results show that, as Ln rises from 5 to 13 m, the formation of the MPW peak is continuously delayed, and the peak value of the MPW decreases; while the optimal L1 remains at 20 m for different Ln. Additionally, the optimal S1 scarcely changes with the increase in Ln as well, between 151 and 156 m2, and its ratio to the section area of the main tunnel (70 m2) is approximately 2.2. The optimal parameters of the entrance expansion section play a universal role for trains with different Ln, which can alleviate the MPW amplitude with a value of 58% or higher. The findings can provide significant support for designing tunnels and tunnel hoods, focusing on alleviating acoustic noise.

A seven-year analysis of the tourism sector of India with a prediction model—A case study of smart tourism

<p>The tourism sector requires an in-depth analysis and forecasting to bring a clear picture of various factors that affect the visit of foreign tourists to certain countries. In this context, the work carried out in this paper provides an in-depth analysis of the number of tourists to India and the revenue generated from them from the year 2014 to 2020. Furthermore, the analysis of different states of India to which the tourists visited the most and quarterly analysis of the tourists to India are also presented. The impact of corona pandemic on the tourism sector of India is also shown by comparing the number of tourists in 2019 and 2020. Support vector regression (SVR) is trained with the historical data of the number of tourists from 2001 to 2016 and validated for 2017 to 2019. This trained model is used to forecast the number of tourists from 2020 to 2023 to study the impact of corona pandemic on the number of foreign tourists to India. Similarly, the historical data of foreign exchange fees from 2001 to 2016 is used to train the model while it is validated with data from 2017 to 2019. This train model is used to predict the Foreign Exchange Earning (FEE) for the years 2020 to 2022. The actual FEE is compared with the predicted FEE to show the impact of the coronavirus pandemic on the revenue generated from tourism by India.<strong></strong></p>

A Model of Accident Avoiding System for Trains

Abstract: Safety must be the top most priority in train running and it plays an important role in safe running of trains in our country. Already many systems are existed to avoid accidents, even though an attempt is made in this project work to study the subject of train accidents avoiding systems to enhance the technology further. The Train Collision Avoidance System (TCAS) is the major subject to detect unsafe situations arising due to over speed and train collisions in station area. The advanced accident prevention methods must be incorporated those measures under which the trains will be in constant communication with the protection systems through electronic communication systems. Although, Indian Railways have safe running devices, we have made an effort to cover few more important features like, 1 – to detect the track break in running rail track, 2 – object detection in between the tracks with auto control, and 3 – auto stop when train detects Red signal present over the track side signal post. These are the three important parameters incorporated in our project work and for live demo, a mini model train will be constructed over which all required sensors and their control circuits will be installed to prove the theme practically.

Nonlinear impedance characteristics of a gas hydraulic energy absorber and performance prediction for railway transportation of valuable goods

It is meaningful to investigate the nonlinear impedance characteristics of gas hydraulic energy absorbers (GHEAs) and their potential application in modern railway transportation of valuable goods. Fluid-mechanics-based full parametric modelling of a GHEA used in a high-speed train is performed, both simulations with the developed mathematic model and physical experiments are carried out on the static and dynamic characteristics of the GHEA. The agreement between the results of the simulation and the experiment with tolerable deviations validates the nonlinear mathematic model. Longitudinal train dynamics (LTD) modelling and simulation of a Chinese rapid freight train with the validated GHEA model or the conventional MT-2 friction-type energy absorber model is finally conducted. The results show that when the train uses GHEAs instead of MT-2 energy absorbers, the coupler forces and vehicle accelerations of the train are significantly reduced, and the vehicles operate more steadily in situations such as train startup, emergency braking and shunting operations; thus, gas hydraulic energy absorber is protective and would be alternative for equipping rapid freight trains for the transportation of valuable goods. The obtained nonlinear mathematic model in terms of the structural, oil and gas property parameters of the GHEA is useful and meaningful in further parameter design optimization of GHEAs and optimal specification of GHEAs for rapid freight trains.

Optimal allocation method of electric/air braking force of high-speed train considering axle load transfer

Reasonable distribution of braking force is a factor for a smooth, safe, and comfortable braking of trains. A dynamic optimal allocation strategy of electric-air braking force is proposed in this paper to solve the problem of the lack of consideration of adhesion difference of train wheelsets in the existing high-speed train electric-air braking force optimal allocation strategies. In this method, the braking strategy gives priority to the use of electric braking force. The force model of a single train in the braking process is analyzed to calculate the change of adhesion between the wheel and rail of each wheelset after axle load transfer, and then the adhesion of the train is estimated in real time. Next, with the goal of maximizing the total adhesion utilization ratio of trailer/motor vehicles, a linear programming distribution function is constructed. The proportional coefficient of adhesion utilization ratio of each train and the application upper limit of braking force in the function is updated according to the change time point of wheelset adhesion. Finally, the braking force is dynamically allocated. The simulation results of Matlab/Simulink show that the proposed algorithm not only uses the different adhesion limits of each trailer to reduce the total amount of braking force undertaken by the motor vehicle, but also considers the adhesion difference of each wheelset. The strategy can effectively reduce the risk and time of motor vehicles during the braking process and improve the stability of the train braking.

Learning Domain Specific Sub-layer Latent Variable for Multi-Domain Adaptation Neural Machine Translation

Domain adaptation proves to be an effective solution for addressing inadequate translation performance within specific domains. However, the straightforward approach of mixing data from multiple domains to obtain the multi-domain neural machine translation (NMT) model can give rise to the parameter interference between domains problem, resulting in a degradation of overall performance. To address this, we introduce a multi-domain adaptive NMT method aimed at learning domain specific sub-layer latent variable and employ the Gumbel-Softmax reparameterization technique to concurrently train both model parameters and domain specific sub-layer latent variable. This approach facilitates the learning of private domain-specific knowledge while sharing common domain-invariant knowledge, effectively mitigating the parameter interference problem. The experimental results show that our proposed method significantly improved by up to 7.68 and 3.71 BLEU compared with the baseline model in English-German and Chinese-English public multi-domain datasets, respectively.

Multi-objective optimisation of wheel-rail adhesion for high-speed trains with aerodynamic lift wings

A high-speed train with aerodynamic lift wings (aero-wings) is designed to improve train speed and mitigate energy consumption. Nevertheless, the impact of aero-wings on wheel-rail adhesion and safety remains uncertain. In this examination, a multi-body dynamics (MBD) model of a high-speed train integrated with aero-wings was first created. The influences of train speed, wheel-rail contact conditions, and aerodynamic lift on the wheel-rail adhesion, wheel wear, and dynamics performance were briefly investigated, indicating that aerodynamic lift degrades wheel-rail adhesion and dynamics performance but reduced wheel wear. Then, the multi-parameters matching optimisation design for sufficient wheel-rail adhesion and minimal wheel wear was conducted. The results indicate that, under dry contact and traction conditions, the minimum wear and optimal wheel-rail adhesion can be achieved when the train speed is about 440.62 km/h, the aerodynamic lift is about 24.48% of the vehicle weight, and the wheel wear optimisation rate is 25.38%. While the train speed of 549.54 km/h and an aerodynamic lift of 12.39% corresponds to the optimal results with wear reduction of 11.62%, under wet and braking conditions. This study provides valuable insights for determining aerodynamic load limits and formulating traction/braking control strategies for high-speed trains with aero-wings.

Floor vibration predictions based on train-track-building coupling model

With the objective of rational urban space utilization, the development of elevated metro depots and over-track buildings is progressing rapidly, with a particular focus on addressing the vibrations caused by trains. Unlike traditional metro depots, trains in elevated depots run on concrete floors, which may lead to excessive floor vibrations. Therefore, it is essential to evaluate the impact of these vibrations during the design phase. In this paper, a vertical vibration prediction model for trains running on building floors is proposed by integrating the train, track structure, and building structure into a unified system. The train model is conceptualized as a multi-rigid body connected by springs and dampers. The track structure comprises rails, fasteners, and track slabs. The building floor is simplified as a rectangular plate composed of multiple orthogonal structural girders and columns in vertical contact with the floor. To verify the proposed method, field measurements were conducted in an elevated metro depot. The proposed model provided estimates of the vibration transmission with good agreement from track to building floor by comparing with the measured vibrations. The model presented in this paper can be utilized to predict the base vibrations of buildings and further predict the floor vibrations.

Dynamic model of high-speed maglev train-guideway bridge system with a nonlinear suspension controller

To improve the anti-interference ability of maglev trains, a dynamic model of the high-speed maglev train with a nonlinear suspension controller for the guideway system is proposed in this paper. Based on the nonlinear characteristics of the magnetic suspension system, a nonlinear decoupling controller is designed using the feedback linearization theory. Then, a high-speed maglev train model is refined with a guideway coupling system, consisting of a maglev train simulated as a multi-body dynamics model with 537 degrees of freedom and a spatial finite element model of the guideway. Taking the Shanghai high-speed maglev train as an example, the correctness of the computational model is verified by comparing the modeling results with field measurement data, and the control effectiveness of the nonlinear controllers and the traditional PD controllers is compared considering different train speeds and disturbance forces. The results show that the suspension gap under the decoupling control is smaller than that under the PD control during the train operations. Under the same disturbance force, the decoupling control exhibits better control performance than the PD control. The variation amplitudes of the magnetic pole gaps are generally linearly related to the disturbance force.

МЕТОДИКА ОЦЕНКИ КОМФОРТНОСТИ ПЕРЕВОЗКИ ПАССАЖИРОВ ЖЕЛЕЗНОДОРОЖНЫМ ТРАНСПОРТОМ ДЛЯ МИНИМИЗАЦИИ РИСКОВ СВЯЗАННЫХ С ЧЕЛОВЕЧЕСКИМ ФАКТОРОМ В ПРОЦЕССЕ ВЕДЕНИЯ ПОЕЗДА

The paper solves the problems of assessing the smooth running of a passenger train, the quality and comfort of passenger transportation by rail, as well as determining the level of professional competencies of locomotive crew members. A comprehensive computer model of a passenger train is developed, which makes it possible to study all the processes of controlling traction equipment and train brakes that affect energy efficiency, safety and dynamics of rolling stock. Using fuzzy logic tools, a technique is developed for rating employees of locomotive crews according to the criterion of ensuring smooth running of the train. The results of experimental trips by passenger trains on sections of the North Caucasus Railway are presented. The dependences of the locomotive traction force, the speed and the longitudinal jerk of the passenger train cars are obtained.

Study on Dynamic Damage of Crash Barrier under Impact Load of High-Speed Train

The derailment of a high-speed train in a tunnel will cause a very serious accident, but there are few research articles on anti-collision facilities in tunnels. In order to promote the sustainable development of high-speed trains and reduce the severity of accidents caused by derailment in tunnels of high-speed trains, this paper puts forward a crash barrier scheme in tunnels through the method of numerical simulation; the coupling finite element model of train–crash barrier–tunnel is established by using ABAQUS. The changes in lateral velocity and lateral displacement after the train hits the crash barrier without embedding steel bars are explored. We also explore the influence of different reinforcement amounts on the changes in the lateral speed and lateral displacement of trains under the condition of embedding steel bars. The results show that with the increase in stirrups and vertical reinforcement, the anti-impact and sustainable operation capability of the crash barrier are greater. It can also be seen from the lateral displacement of the train that the train shows the reverse movement trend, and the crash barrier plays a good role in intercepting the train. These research results can provide a reference for the sustainable development of transportation infrastructure construction.

The effect of floating spline parameter on the dynamic characteristic of encased differential planetary gear train

The load sharing performance of encased differential planetary system has a great impact on the operating performance and service life of the transmission system of the coaxial high speed helicopter. In order to improve the load-sharing performance of the gear pair, the influence of different floating spline structural parameters on the load sharing characteristics of the system was studied. Considering the manufacturing error, installation error, time varying meshing stiffness and other factors, the Lagrange equation is used to construct the dynamic model of encased differential planetary gear train with floating spline structure. The effects of input torque, spline clearance, spline shaft stiffness and spline friction coefficient on the load sharing performance of gear pairs were analyzed. The results show that the differential stage system has a better load sharing performance than the encased stage system. The increase of input torque helps to improve the load sharing performance of the system, and the improvement of the encased stage system is more obvious. The floating spline of sun gear of the encased stage has a greater impact on the load sharing performance of the system. Furthermore, increasing the floating spline clearance, reducing spline shaft stiffness or increasing the friction coefficient of the spline can improve the load sharing performance of the system overall.

NeTrainSim: a network-level simulator for modeling freight train longitudinal motion and energy consumption

AbstractAlthough train modeling research is vast, most available simulation tools are confined to city- or trip-scale analysis, primarily offering micro-level simulations of network segments. This paper addresses this void by developing the NeTrainSim simulator for heavy long-haul freight trains on a network of multiple intersecting tracks. The main objective of this simulator is to enable a comprehensive analysis of energy consumption and the associated carbon footprint for the entire train system. Four case studies were conducted to demonstrate the simulator’s performance. The first case study validates the model by comparing NeTrainSim output to empirical trajectory data. The results demonstrate that the simulated trajectory is precise enough to estimate the train energy consumption and carbon dioxide emissions. The second application demonstrates the train-following model considering six trains following each other. The results showcase the model ability to maintain safe-following distances between successive trains. The next study highlights the simulator’s ability to resolve train conflicts for different scenarios. Finally, the suitability of the NeTrainSim for modeling realistic railroad networks is verified through the modeling of the entire US network and comparing alternative powertrains on the fleet energy consumption.

Performance Assessment of Two-Wheeler Electric Vehicle Batteries Using Multi-Mode Drive Cycles

This article presents a model-based approach to assess the battery performance of a two-wheeler EV drive train system for various user driving patterns using the selected urban drive cycles. The battery pack is one of the most expensive parts of an EV, and its life is heavily dependent on its usage pattern. The impact of the user’s driving behaviour on the performance parameters of the EV battery pack needs to be investigated. Thus, a two-wheeler EV drive train model was developed in MATLAB with a 5 kW motor, a 4.32 kWh battery, vehicle dynamics, and the power train control algorithms for in-depth analysis of battery performance. The validity of the developed model was tested against various state-of-the-art drive cycles for a duration of 3600 s. Numerous user driving behaviours, such as aggressive, moderate, and slow driving behaviours, were modelled with modified drive cycles, which were used to assess the two-wheeler battery pack performance. An optimum speed range, which ranges from 21 km/h to 34 km/h for different drive cycles, was identified, and these speed ranges minimised the battery energy consumption for the selected drive cycles with the modified drive cycle models.

High-Speed Train Running Characteristics Assessments Using Multibody Dynamics Simulation

The development of railway transportation in Indonesia in recent years has increased the number of new vehicles with various types and specifications. These new vehicles should pass a series of running characteristics assessments against standards to ensure safety and comfort in operation. Before the field testing, the assessments using numerical simulation in the design stage need to be done. This study aims to assess the high-speed train running characteristics through modeling and testing using multibody dynamics simulation software. The standards used for the assessments refer to EN 14363 – Testing and Simulation for The Acceptance of Running Characteristics of Railway Vehicles. The high-speed train model was built and validated through four methods with comparative values calculated analytically. The validated model was then run in the simulation to get the parameters for assessment. The parameters include the coefficient of flexibility, critical speed, safety against derailment with various methods, ride comfort, and vibration mode. The parameters obtained from the simulation are compared to the acceptance criteria specified in the standard. The results show that the vehicle performance fulfills the requirement prescribed by EN 14363 standard. After the vehicle and the track infrastructure are ready, they need to be confirmed by a series of testing performed on the main line. This study supports the development of high-speed trains in Indonesia and is expected to give more insight into the usefulness of numerical simulation to predict the characteristic of dynamic performances of railway vehicles in actual operating conditions.