Rail Transport System Research Articles

Automatic Crack Segmentation for UAV-Assisted Bridge Inspection

Bridges are a critical piece of infrastructure in the network of road and rail transport system. Many of the bridges in Norway (in Europe) are at the end of their lifespan, therefore regular inspection and maintenance are critical to ensure the safety of their operations. However, the traditional inspection procedures and resources required are so time consuming and costly that there exists a significant maintenance backlog. The central thrust of this paper is to demonstrate the significant benefits of adapting a Unmanned Aerial Vehicle (UAV)-assisted inspection to reduce the time and costs of bridge inspection and established the research needs associated with the processing of the (big) data produced by such autonomous technologies. In this regard, a methodology is proposed for analysing the bridge damage that comprises three key stages, (i) data collection and model training, where one performs experiments and trials to perfect drone flights for inspection using case study bridges to inform and provide necessary (big) data for the second key stage, (ii) 3D construction, where one built 3D models that offer a permanent record of element geometry for each bridge asset, which could be used for navigation and control purposes, (iii) damage identification and analysis, where deep learning-based data analytics and modelling are applied for processing and analysing UAV image data and to perform bridge damage performance assessment. The proposed methodology is exemplified via UAV-assisted inspection of Skodsberg bridge, a 140 m prestressed concrete bridge, in the Viken county in eastern Norway.

Research on deep learning method for rail surface defect detection

Rail surface defect detection plays a critical role in the maintenance of the rail transportation system. Video analysis technology is a promising method to detect defects due to its low cost and effectiveness. Several attempts with hand-craft features have been made to obtain the detection results by using traditional machine vision algorithms. However, these methods suffer from imprecise results due to challenging conditions, such as deteriorated and changeable lighting environment and various types of complex rail surface defects. Recently, classification methods with complex deep convolutional networks have become popular. Despite their high accuracy, these methods cannot meet the requirements of defects localisation and real-time processing in practice. To solve these problems, this study proposes a novel object detection algorithm to detect rail defects. The net architecture of the proposed algorithm includes a backbone network using MobileNet and several novel detection layers with multi-scale feature maps inspired by you only look once (YOLO) and feature pyramid networks. Two different architectures of MobileNet are used to estimate the performance of defects detection. The experimental results demonstrate the great potential of the proposed algorithm with fast inference speed and high accuracy in the industry.

Rapid ‘fingerprinting’ of potential sources of plastics in river systems: an example from the River Wye, UK

ABSTRACT Literature review identified seven principal pathways of plastic debris entry into river systems: waste water treatment plants; combined sewer overflows; on-site wastewater treatment systems; road and rail transport systems; agriculture; industrial sources; and diffuse litter. A further category of ‘microplastics’ reflects their multiple potential sources, including microplastic breakdown within rivers. Regulatory and management bodies necessarily make operational decisions based on resource limitations and significant uncertainty due to sparse or missing data, requiring a substantial degree of inference. To support this need, we develop a rapid, desk-based approach based on risk criteria to ‘fingerprint’ likely pathways of plastic pollution based on catchment characteristics. Characteristics of the River Wye system in the UK are reviewed identifying a risk-based ‘fingerprint’ of potential pathways of plastic entry or accumulation of plastic debris, represented graphically as a colour-coded ‘traffic lights’ classification. This ‘fingerprinting’ approach is based on desk-based inference from published materials as a rapid and resource-efficient alternative to intensive data collection, supporting prioritization of further investigation or response measures. We recommend replication of this ‘fingerprinting’ approach in other river catchments to support operational management of plastic pollution. Where feasible, it may also be down-scaled where sub-catchment or major river reach properties differ significantly. HIGHLIGHTS Unique catchment characteristics influence likely sources of plastics in rivers Seven potential plastic sources were identified, with a residual microplastics category Literature, interviews and surveys can rapidly ‘fingerprint’ likely plastic sources Fingerprinting can prioritize management and investigations in specific catchments

Mobile relays for urban rail transportation systems

Assuring an uninterrupted high Quality of Service (QoS) of railway communications between on-board terminals and base stations creates challenges for the provider. This is partly explained by the inherent mobility and the high penetration loss of carriages. Deploying mobile relays in public transportation is possible with a 100%-compatible LTE/EPC architecture. This effectively ensures that the electromagnetic insulation is kept to a minimum as QoS on board can be dramatically affected and worsened within the railway vehicles. Yet all users’ traffic congregates via the radio backhaul link and needs to take into consideration the extra packet-overhead and signaling messages that as a general rule get transmitted via the fixed links. The paper’s aim is to analyze the performance of mobile relays in loaded conditions comparing this to the standard direct mode. We propose an analytical model to compute the signaling rate. We parametrize it with experiments done on a testbed with real radio transmissions and show that signaling has no major impact on performance. We then evaluate the QoS experienced by passengers by means of simulations for two representative services: Web browsing and voice communications. The packet loss ratio for voice communications is reduced at the expense of a slight end-to-end latency increase thanks to mobile relays. During the high load conditions there is a significant reduction in the load time of a Web page and the throughput is increased.

Model Optimization for A Dynamic Rail Transport System on an Asymmetric Multi-Core System

The problem of optimization of the rolling dynamics model is considered. That providing safe movement at high frequency when interacting with the railway. Moreover, allowing to evaluate the dynamic parameters when designing new and modernizing existing locomotives. The object of this research is a rail transport dynamic system model. The article's purpose is to increase the efficiency of the digital hardware in the rolling stock loop model by optimizing the organization of the computing process. The mathematical model analysis of the object made it possible to attribute it to the class of hard real-time systems. The computation of the model phase variables with different frequencies is necessary to optimize the simulation time of the train movements and is performed by splitting the original algorithm into parallel threads. The developed planning algorithm and the cyclic schedule implementation for the model of a dynamic real-time object consider microarchitecture solutions of symmetric multiprocessor systems with shared memory and methods for optimizing software tools. The experiments confirmed the operability of the optimized model. Also, allow us to recommend it for practical use in studying objects and determine the dynamic force of trolley structural elements during operation. Analysis of the optimized model simulation results, using cyclic schedules shows the correspondence of the obtained simulation results to the standard. The main advantage of the model is the increase in productivity when performing data processing by reducing the processor time. The optimized cyclic schedule algorithm of the semi-natural modeling platform is used for the subsequent development of the control system in real and accelerated time scales.

Climate change research on transportation systems: Climate risks, adaptation and planning

With the occurrence of more frequent and intense climate change events, transportation systems, including their infrastructure and operations become increasingly vulnerable. However, the existing research related to climate risks, adaptation and planning in the transport sector is still at an embryonic stage. Understanding such, this paper presents a critical review on climate risks, adaptation strategies and planning in the context of road and rail transportation systems. It aims to conduct a rigorous survey, to highlight any significant research gaps not addressed in past studies and to analyse current emerging topics to guide future directions. It critically dissects the selected papers by categorising them into several dimensions to reveal the status quo and potential challenges, including climate risk assessment, transport asset management, climate planning and policy, and adaptation of transport infrastructure to climate change. It will provide valuable references for future research and constructive insights and empirical guidance on climate adaptation, risk analysis, transport planning and other important relevant topics.

Linear angular momentum multiplexing-conceptualization and experimental evaluation with antenna arrays.

Linear angular momentum multiplexing is a new method for providing highly spectrally efficient short-range communication between a transmitter and receiver, where one may move at speed transverse to the propagation. Such applications include rail, vehicle and hyperloop transport systems communicating with fixed infrastructure on the ground. This paper describes how the scientific concept of linear angular momentum multiplexing evolves from orbital angular momentum multiplexing. The essential parameters for implementing this concept are a long array at least at one of the ends of the link; antenna element radiation characteristics and the array element spacing relative to the propagation distance. These parameters are also backed by short-range measurements carried out at 2.4 GHz used to model the Rice fading channel and determine resilience to multipath fading.

Dynamic behaviour of bridges under critical articulated trains: Signature and bogie factor applied to the review of some regulations included in EN 1991-2

The information contained in this paper will be of interest not only to bridge engineers, but also to train manufacturers. The article provides practical insight into the degree of coverage of real articulated trains (ATs) that Eurocode EN1991-2 guarantees. In both the design of new railway bridges, as well as in the assessment of existing ones, the importance of a detailed knowledge of the limits of validity of load models cannot be overemphasised. Being essential components of the rail transportation system, the capacity of bridges to withstand future traffic demands will be determined precisely by the load models. Therefore, accurate definition of the limits of validity of such models reveals crucial when increased speeds and/or increased axle loads are required by transportation pressing priorities. The most relevant load model for a significant portion of the bridges in high-speed railway lines is the so-called HSLM-A model, defined in EN1991-2. Their limits of validity are described in Annex E of such code. For its singular importance, the effects of vibrations induced by HSLM-A are analysed in this paper with attention to the response of simply supported bridges. This analysis is carried out in a view to determine whether the limits of validity given in Annex E of EN1991-2 cover the largest part of cases of interest. Specifically, the vibration effects of HSLM-A are compared with those of the ATs described in such Annex E, and the response is analysed in depth for simply supported bridges, which are structures especially sensitive to passing trains at high speeds. New theoretical approaches have been developed in order to undertake this investigation, including a novel, simplified expression of the train signature for ATs that is convenient for its low computational cost. The mathematical proofs are included in the first part of the paper and two separate appendices.

Characterization of used and virgin pearlitic rail steel

Rail transport system experience complex loading conditions that alters the microstructure of wheel and rail material near the contact interface region. This paper presents microstructure and hardness study of virgin and used pearlitic rail steel. Samples are prepared from the railhead section taken from nearby Kazipet Railway Division, (South Central Railway). The microstructure and hardness variation along the depth from the surface is presented. In continuation to the author’s previous study [1], along the transverse direction, this time samples are taken in a longitudinal direction. Microstructural observations show the existence of pro-eutectoid ferrite at the grain boundaries for the sample near to the rail surface. Presence of this softer material favours micro-crack initiation causing wear debris formation and rolling contact fatigue defects. Hardness test results reveal an increase in hardness values for material points close to the surface, while base material hardness remains almost the same. Higher hardness values at the surface level are indicating the formation of a brittle material which is more susceptible to crack initiation and propagation. This experimental investigation enriches knowledge domain in the formation of rolling contact fatigue defects. This will help railway engineers to schedule proper maintenance planning and material scientists to develop superior rail material.

Opportunities for Development of City Rail Transport System and Network in Nur-Sultan (Astana)

Opportunities for Development of City Rail Transport System and Network in Nur-Sultan (Astana)

WIRELESS WI-FI SECURITY ANALYSIS IN AUTOMATED RAILWAY SYSTEMS

Purpose. The article is aimed to analyze the basic security mechanisms available in Wi-Fi networks; show the mechanisms for attacking these defenses; carry out a comparative analysis of the effectiveness of protection mechanisms; provide recommendations for the use of these mechanisms in automated rail transport systems; build a demonstration model of attacks on Wi–Fi network security. Methodology. Based on the review of a significant number of domestic and foreign sources, a comparative analysis of the security mechanisms of the Wi–Fi network is carried out, where individual protection standards are analyzed, their strengths and weaknesses appear. A variety of attacks on authentication tools and mechanisms for ensuring the security of information exchange are shown. To demonstrate an attack on these security features, an algorithm has been developed for a demonstration simulation model of the WPA2 security protocol with the ability to attack this protocol. Findings. The basic standards of Wi–Fi security mechanisms have been compared. In particular, WEP, WPA, WPA2, WPA3. Different attacks on these standards have been demonstrated. The advantages and weaknesses of individual mechanisms of protective means are shown, recommendations for their use are provided. A demonstration model of attacks on wireless network protection mechanisms has been built, which demonstrates such attacks as an attack on a passphrase and a KRACK attack. To demonstrate in the program, the WPA2 standard with the PSK authentication mechanism and the cryptographic protection mechanism CCMP-128 is chosen. Originality. A wide range of Wi–Fi network security mechanisms is presented, the capabilities of individual security mechanisms are shown, and Wi–Fi network security standards are compared. The original software model shows how erroneous user actions help an attacker overcome modern security mechanisms. Practical value. Recommendations for the use of separate Wi-Fi security features can be used to build a security system for individual components of automated rail systems. A demonstration model of an attack on a Wi-Fi network can be used in a training process to train cybersecurity specialists.

Application of artificial neural network to predict amount of carried weight of cargo train in rail transportation system

<span lang="EN-US">Derailments of cargo have frequently occurred in Malaysian train services during the last decade. Many factors contribute to this incident, especially its total amount of carried weight. It is found that severe derailments cause damage to both lives and properties every year. If the amount of carried weight of cargo train could be accurately forecasted in advance, then its detrimental effect could be greatly minimized. This paper presents the application of Artificial Neural Network (ANN) to predict the amount of carried weight of cargo train, with KTMB used as the study case. As there are many types of cargo being carried by KTMB, this study focuses only on cement that being carried in twelve (12) different routes. In this study, Artificial Neural Network (ANN) has been incorporated for developing a predictive model with three (3) different training algorithms, Levenberg-Marquardt (LM), Quick Propagation (QP) and Conjugate Gradient Descent (CGD). The best training algorithm is selected to predict the amount of carried weight by comparing the error measures of all the training algorithm which are Root Mean Squared Error (RMSE) and Mean Absolute Percentage Error (MAPE). The obtained results indicated that the ANN technique is suitable for predicting the amount of carried weight.</span>

Application of Case-Based Reasoning to the safety assessment of critical software used in rail transport

The risk assessment of railway accidents requires the implementation of several safety analysis methods such as Preliminary Hazard Analysis, Functional Safety Analysis, Analysis of Failure Modes, their Effects and their Criticality and Software Error Effect Analysis (SEEA). The study proposed within the framework of this article concerns the SEEA method whose objective is to determine the nature and severity of the consequences of software failures, to propose measures to detect errors and improve the robustness of the software. The goal is to develop a new approach to analysis and evaluation of the safety of critical software, based on machine learning and more precisely on the Case-Based Reasoning (CBR). The approach adopted involves two main activities: The first step in acquiring safety knowledge consists in extracting, modeling and archiving dangerous situations to produce a library of standard cases which covers the entire problem. The second stage of machine learning is to exploit historical knowledge (experience feedback) in order to assist safety experts in their critical task of analyzing and assessing the safety of software involved in guided or automated rail transport systems. This second activity involves the use of Case-Based Reasoning (CBR).

Assessing the Existing Bursa Light Rail Transportation System

As car ownership soars, traffic congestion and its associated negative impacts have become real concerns in many cities around the world. Therefore, transportation systems that perform better in eliminating or reducing traffic congestion and related problems to tolerable levels have become imperative. Alternative transit systems should be assessed properly to accommodate the expected demand in the long term, at least, to some significant extent. However, this is generally neglected in developing countries and, among many possible alternatives, a popular transportation system is usually preferred within the available budget. As an example, Bursa Metropolitan Municipality, Turkey, has recently implemented a light rail transportation system (LRT) on its major east–west corridor as the main transit system. In this study, the existing LRT is assessed and its performance is compared with a hypothetical bus rapid transit (BRT) system, which is a strong contender and comparatively a lower-cost alternative. This is done to assess whether the LRT was the better choice in relation to the current demand. Therefore, in this study, the existing LRT system is first defined in the PTV VISSIM simulation environment. Then, the hypothetical BRT system is considered on the same route with the current demand. The capability and capacities of the existing LRT and the BRT system are assessed and compared in many aspects. The results are compared, and important findings are outlined.

Exploring the Interoperability of Public Transport Systems for Sustainable Mobility in Developing Cities: Lessons from Johannesburg Metropolitan City, South Africa

There have been growing concerns with regards to the state public transportation systems, particularly in the cities of developing countries. Chief among these concerns has been the lack of well-coordinated, efficient, and reliable transportation systems. The city of Johannesburg, just like any other fast-growing municipality in developing and emerging economies, has not been spared with regards to incessant public transport challenges. Consequently, there have been collective efforts from both public and private stakeholders to invest immensely in both innovative rail and road transport systems in the past decade. This article sought to achieve twin objectives. First, the work identified the state of connectivity between the rapid rail transportation and rapid bus transit systems based on Geoweb 2.0 data. Second, the work visualized the level of connectivity between these two modes to develop and formulate policy frameworks in integrating public transit systems in cities of the developing world, learning from the metropolitan city of Johannesburg. A mixed-method approach consisting of spatial and quantitative aspects was used to examine the state of connectedness and the promotion of access and mobility between the two modes. The local Moran’s I index was used to compute node clusters within the public transport system. Results from the analysis demonstrated that both high-clusters and low-clusters exist in the public transportation network, which have a high degree of centrality. It was revealed that commuters navigate from these nodes/stops with relative ease due to the short walking radius. However, the work revealed that most rail networks and bus routes, as well as the stations and bus stops, are not connected and are not significant in the local Moran’s I index, thus, making it difficult for commuters to conveniently move from the Gautrain to the Rea Vaya bus. There are, therefore, gaps with regards to the sharing of infrastructure between the two public transport modes and systems.

Estimation of direct energy consumption and CO2 emission by high speed rail, transrapid maglev and hyperloop passenger transport systems

This paper deals with estimation of direct energy consumption and related emissions of GHG exclusively, including CO2, by the High Speed Rail (HSR), Trans Rapid Maglev (TRM), and Hyperloop (HL) passenger transport systems. This includes developing the corresponding analytical models based on the mechanical energy and applying them according to the specified what-if operating scenarios. The analogous models are developed and applied to the Air Passenger Transport (APT) system for comparison purposes. The results of the application of the proposed models under given conditions have indicated that the average and total energy consumption and related emission of CO2 of the three systems have been generally sensitive, i.e. elastic to variations of the nonstop journey distance and the vehicle/train seating capacity. Their average values have decreased more than proportionally and total values in proportion with increasing of the nonstop journey distance. Both have decreased with increasing of the vehicle/train seating capacity per departure. In the case of supplying equivalent equally utilized transport capacities, the HSR and the TRM have had lower energy consumption and related emission of CO2 than the HL system. As well, the HSR, the TRM, and the HL have had lower energy consumption and related CO2 emission than the selected APT aircraft up to some ‘breaking’ journey distance under given what-if operating scenarios.

Model‐Based Systems Engineering for complex rail transport systems – A case study

AbstractThe replacement of the signalling and control systems on Sydney's critical heavy‐rail network infrastructure is envisaged to take years and affect many systems across the operational railway. Systems Engineering has been adopted early in the system lifecycle to manage the complexity and risks in a rigorous and consistent manner. This paper aims to document the real‐life application of a Model‐Based Systems Engineering (MBSE) methodology in the conceptual design stage on Transport for New South Wales’ Digital Systems Program. It illustrates how this methodology was applied to capture the operational and maintenance concepts, derive the architecture and interfaces and guide resulting requirements. It provides valuable lessons‐learnt for the acquiring organisation on the deployment of MBSE, its benefits and lessons learnt.

Melbourne's Advanced Rail Transportation

Melbourne's commuter rail transportation is ageing and outdated. As Melbourne's population is ever-increasing, its rail transportation infrastructure planning also needs to be developed, based on long-term technological advancements. Subsequently, Melbourne's rail network and its systems need to be continuously scrutinized. This study thus reviews Melbourne's advanced rail transportation systems, and determines its future perspectives. This research initially found that, for Melbourne, one of the important aspects of long-term technological innovation is the inclusion of the three specific automation measures of; moderate intrusion control systems; revamp signaling technologies; and new rail lines and systems. Further examination recommended that advanced rail transportation systems including enhanced communications systems, be carefully integrated. Such outcomes will in turn boost Melbourne's rail performance through, a) increase safety and passenger satisfaction; b) enhance system reliability; c) intensify train frequency and capacity; d) improve operational flexibility; and e) reduce the overall operating costs. It is expected that these findings will ultimately assist the relevant rail transportation planners, to make optimal decisions when deciding on the selection of the most advanced rail transportation strategies.

Understanding the costs of urban rail transport operations

There is considerable variation in the average cost of operations across urban rail transport (or metro) systems. Since metros are typically owned and operated by public authorities, there is a public interest case in understanding the key drivers of their operational costs. This paper estimates short-run cost functions for metro operations using a unique panel dataset from twenty-four metro systems around the world. We use a flexible translog specification and apply dynamic panel generalised method of moments (DPGMM) estimation to control for confounding from observed and unobserved characteristics of metro operations. Our empirical results show that metro systems with a high density of usage are the most cost-efficient. We also find that operational costs fall as metro size increases. These results have important implications for the economic appraisal of metro systems.

Literature Review on the Rail Transport Schedule Robustness

Abstract The article presents issues concerning rail transport (rail, metro and tramway) and factors influencing the planned implementation of the schedule. At the beginning, the scope of application of the robustness concept was analysed, based on scientific and industry literature. Then the attention was focused on the model of the rail transport system and the schedule, the basic indicator of robustness assessment was discussed, taking into account the methods of analysis used and many variables occurring in rail transport. Finally, a review of the state of knowledge is summarised and the most important observations from the analysis are indicated. In the case of a robust schedule there is no propagation of disruption across the network after an adverse event has occurred.