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Real-time train rescheduling for high-speed railway (HSR) is a pivotal technique in HSR transportation to efficiently recover train operation under disturbance scenarios. This paper aims to put forward an integrated resolving and rescheduling method considering network delay propagation. A tree-based conflict resolution mechanism is first established, with delicate considerations on the strategy's adaptability under different conflict scenarios. By inputting the scheduled arrival and departure time under different conflict resolution strategies, the timetable optimizing model aims to look for an optimal solution with minimal weighted train delay and average train adjustments under necessary technical and empirical constraints solved by a combined algorithm of Pareto optimality and Nash equilibrium, where the feasible solution space is narrowed in advance by a depth-first pruning algorithm. The performance of this coordinated train rescheduling approach is validated by a typical section disturbance in a regional HSR network administrated by the Shanghai Bureau. The results show that the proposed method can well utilizes timetable buffers and organizes train avoidance. The delay propagation characteristics are also simultaneously estimated based on the indicators of cumulative delay and instantaneous delay, which are established considering the spatio-temporal difference between the scheduled and planned timetables, in order to verify the coordination between resolution strategies and train running delays., Author(s): Jun Zhang (corresponding author) [1]; Shuyao Wu [1]; Shejun Deng [1]; Yuling Ye [2] 1. Introduction Under the network transportation of high-speed railway (HSR), disturbances of abnormal events are [...]

Since unexpected event occurrences are inevitable, an efficient and effective rescheduling approach is critical in freight railway day-to-day operations. Represented by the minimal-delay objectives, the most commonly used efficiency-oriented approach ignores the role of train priority and poses equity problems in rescheduling. For equity, different train priority also reflects the preference in deciding train orders; i.e., the high-priority train is likely to be favorable. However, a conflict may be laid between reducing delays and emphasizing train priority. Hence, it is critical to decide the criteria in train order for freight railway, especially with heterogeneous priority in a competitive resource. To make a tradeoff between equity and efficiency, this paper makes train priority evolutionary and proposed the dynamic train priority considering delay time and static priority. We formulate an optimization model based on the rescheduling strategies such as retime, reorder, and retrack in a complex railway network containing single-track, double-track, and quadruple-track sections. An integrated two-dimension genetic algorithm (ITGA) approach is developed to reobtain an optimized timetable of sufficient quality while meeting the time requirements for real-time rescheduling. In the experiment, the effectiveness of the ITGA approach was employed in a simple case and a real-world case in the Netherlands freight railway. The result shows that there is a synergy between delay time and train priority, where the threshold to upgrade the evolutionary train priority plays an important role. The proposed approach is compared with the benchmark solution first-in-first-out (FIFO) approach in a real-world case to verify the performance and efficiency. Our work extends the rescheduling approach considering both equity and efficiency and provides auxiliary operation support for the dispatcher's operation rescheduling., Author(s): Zhuotong Bai [1]; Hui Wang [2]; Lin Yang [3]; Jiajie Li [4]; Huapu Lu (corresponding author) [1] 1. Introduction Freight railway holds an increasing market share in transportation systems [...]

Railway freight rates are seen as a key driving factor of global trade activities, influenced by numerous factors. Given the limitations of fuzziness and randomness of variable quantification in the previous studies, this paper proposes a cognitive cloud model of factors influencing railway bulk goods freight rates. In the cognitive cloud model, randomness and fuzziness are described by three parameters. Furthermore, a cloud generator including forwarding and backward cloud generators is designed to solve the bidirectional conversion between qualitative indicators and quantitative values. In addition, we propose a floating cloud gathering algorithm to determine the weight of the index system to solve the uncertainty problem in the transformation process of qualitative indicators. Finally, the cognitive cloud model and the adapted algorithm are used to perform an in-depth analysis of the affecting factors of Z Railway Bureau freight transport pricing., Author(s): Jingwei Guo [1,2,3]; Yimin Wang (corresponding author) [2]; Yang Qin [4]; Qinglin Li [1]; Zhongqi Xie [2]; Xin Qin [2] 1. Introduction To engender effective influencing factors evaluation, various [...]

Railway systems should be resilient to play a key role in creating sustainable development. Single-track railway lines are seen as potential bottlenecks due to limited capacity. More advanced railway interlocking systems (such as ETCS or satellite-based control systems) are being developed. On the other hand, the installation of these interlocking systems is a complex and time-consuming and costly task. For this reason, it is necessary to recognize the impact of potentially installed system with capacity, stability of timetable, quality, and other associated effects. The assessment is based on a set of simulation experiments using stochastic microscopic simulation model in the OpenTrack software tool. The focus is on railway operation with automatic block and automatic line blocking systems. If these two systems will have positive capacity effects, it is a basic presumption also for systems such as moving block (e.g., ETCS L3) to be effective. Research has shown that the significance of such measures can be best supported by linking to a matching timetable concept that will make full use of the benefits offered by these interlocking systems. The results reached in this research should be potentially applied, for example, by prioritizing of single-track railway lines for possible installation of such interlocking system. It can be achieved based on the capacity and operational effects examined., Author(s): Michael Bažant (corresponding author) [1]; Josef Bulíček [2] 1. Introduction Railway industry plays a key role within an effort to create a sustainable environment. The issue is that there [...]

The hierarchical connection of Rail Traffic Management System (TMS) and Automatic Train Operation (ATO) for mainline railways has been proposed for a while; however, few have investigated this hierarchical connection with the real field. This paper studies in detail the benefits and limitations of an integrated framework of TMS and ATO in stochastic and dynamic conditions in terms of punctuality, energy efficiency, and conflict-resolving. A simulation is built by interfacing a rescheduling tool and a stand-alone ATO tool with the realistic traffic simulation environment OpenTrack. The investigation refers to different disturbed traffic scenarios obtained by sampling train entrance delays and dwell times within a typical Monte Carlo scheme. Results obtained for the Dutch railway corridor Utrecht-Den Bosch prove the value of the approach. In case of no disruptions, the implementation of ATO systems is beneficial for maintaining timetables and saving energy costs. In case of delay disruptions, the TMS rescheduling has its full effect only if trains are able to follow TMS rescheduled timetables, while the energy-saving by using ATO can only be achieved with conflict-free schedules. A bidirectional communication between ATO and TMS is therefore beneficial for conflict-resolving and energy-saving., Author(s): Pengling Wang (corresponding author) [1,2,3,4]; Annik Jeiziner [5]; Xiaojie Luan [4]; Valerio De Martinis [4,6]; Francesco Corman [4] 1. Introduction In railway systems, intelligent rescheduling (Traffic Management System, TMS) [...]

The current preemption method for traffic signals at intersections located near highway-rail grade crossings (IHRGC) is known as the standard preemption (SP). The SP strategy is designed to give priority to the phases which clear vehicles off the railroad tracks as quickly as possible before a train arrives at HRGCs and provides the drivers and pedestrians with a minimum warning time (MWT). However, the SP considers neither pedestrian safety nor system efficiency at IHRGCs. As a result, this may lead to safety and delay problems at IHRGCs. To solve the problems, a state-of-the-art transition preemption strategy (TPS) algorithm, named TPS_DT, is developed in this paper. The new TPS algorithm is designed for corridors with multiple HGRCs that have dual tracks. An urban highway corridor with multiple HRGCs in Lincoln, NE, was selected as the study corridor. A calibrated VISSIM model of the study corridor was used to test the safety and efficiency of the proposed algorithm. The algorithm was coded in VAP, which is an add-on module of VISSIM. A roadway-railway corridor with multiple IHRGC and dual rail tracks in Lincoln, NE, was used as the testbed. The Measurements of Effectiveness (MOEs) used for evaluation include the rate of pedestrian phase cutoffs, intersection vehicle delay, and corridor vehicle delay. It was found that TPS_DT can significantly improve pedestrian safety and reduce vehicle delay at IHRGCs. Furthermore, the effects of train arrival prediction errors on safety and efficiency of the IHRGCs are also analyzed in the paper., Author(s): Yifeng Chen (corresponding author) [1]; Laurence R. Rilett [2]; Zifeng Wu [3] 1. Introduction Highway-rail grade crossings are locations where a highway and railway intersect at the same level [...]

Chinese high-speed railway has implemented large-scale network operation with an urgent need for capacity improvement. The concept of virtual coupling seems to be a promising solution that provides a new operational scenario for high-speed railway, where trains are formed into a cooperative convoy and run synchronously with small train headways. The train-following principles under the virtual coupling signalling are quite different from those under conventional train control systems. Therefore, train headway analysis for different operational scenarios should be carried out to ensure railway safety and evaluate capacity benefits brought by virtual coupling. This paper proposes a potential virtual coupling architecture with reference to ETCS/ERTMS specifications. We compare blocking time models under different train control systems, and eight typical train-following scenarios are investigated for virtual coupling, including train arrival and departure cases. A detailed multiscenario-based train headway analysis is provided based on the microscopic infrastructure of the station and technological characteristics of virtual coupling. All computational outcomes are based on the train dynamic motion model. A comparative analysis of train headways under virtual coupling and CTCS-3 is provided in the case study. Results show that train headways can be substantially reduced under virtual coupling and are related to the station infrastructure layout., Author(s): Jinyi Pan [1]; Qiyuan Peng [1,2,3]; Shuguang Zhan (corresponding author) [1,2,3]; Jiaqi Bai [4] 1. Introduction In China's high-speed railways, oversaturated utilization of capacity has become prominent with the [...]

The advantage of multimodal transport is that it can deliver the goods to their destination in a reasonable combination of transport modes while ensuring security and punctuality. Multimodal transportation can effectively reduce logistics costs, improve logistics efficiency, and reduce environmental pollution. In the process of multimodal transportation, due to the interference of natural factors (weather, terrain, etc.) and some special human factors, it may have different degrees of impact on the transportation time and transportation safety of different transportation modes. Therefore, when choosing a transportation method, it is necessary to consider the transportation time and transportation safety under the interference. However, the current research on multimodal transport has not considered the impact of external interference on transportation time and transportation safety. Compared with other modes of transportation, external interference has a relatively small impact on railway transportation. Railways can safely deliver goods to their destinations on time. Under the background of China's huge railway network and advanced heavy-duty technology, this paper establishes a multimodal transport route selection model for considering railway as the core, introduces time penalty cost and damage compensation cost, and takes the lowest comprehensive transportation cost as the model objective under the premise of considering transportation reliability and transportation safety. Finally, taking a multimodal transport network in China as an example, an improved ant colony algorithm is used to solve the model and the results verify the rationality of the model., Author(s): Hui Zhang [1,2,3,4]; Yao Li [1]; Qingpeng Zhang [5]; Dingjun Chen (corresponding author) [1,2,3] 1. Introduction Multimodal transport [1] is a mode of cargo transportation through the connection and [...]

It is known that it is critical for train rescheduling problem to address some uncertain disturbances to keep the normal condition of railway traffic. This paper is keen on a mathematical model to reschedule high-speed trains controlled by the quasi-moving blocking signalling system impacted by multidisturbances (i.e., primary delay, speed limitation, and siding line blockage). To be specific, a mixed-integer linear programming is formulated based on an improved alternative graph theory, by the means of rerouting, reordering, retiming, and train control. In order to adjust the train speed and find the best routes for trains, the set of alternative arcs and alternative arrival/departure paths are considered in the constraints, respectively. Due to this complex NP-hard problem, a two-step algorithm with three scheduling rules based on a commercial optimizer is applied to solve the problem efficiently in a real-word case, and the efficiency, validity, and feasibility of this method are demonstrated by a series of experimental tests. Finally, the graphical timetables rescheduled are analysed in terms of free conflicts of the solution. Consequently, the proposed mathematical model enriches the existing theory about train rescheduling, and it can also assist train dispatchers to figure out disturbances efficiently., Author(s): Peijuan Xu [1]; Dawei Zhang (corresponding author) [2,3]; Jingwei Guo [4]; Dan Liu [1]; Hui Peng [1] 1. Introduction High-speed railway faced a rapid development in the world and [...]

Abstract. This paper evaluates the robustness of a railway network with respect to operational delays. It assumes that trains in the network operate on fixed routes and with reference to [...]

Crew costs are a significant portion of rail operating expenses, and so effective deployment of train crews is an important priority for freight railroads. This paper proposes an optimization model [...]

High-speed railway (HSR) transportation poses a serious challenge to dispatchers, whose job performance plays a critical role for the safety and efficiency of the transportation system. This study examined the relationship between cognitive and mental factors and job performance among Chinese high-speed railway dispatchers and established a predictive model for the job performance of dispatchers. Cognitive abilities involved in train dispatching including working memory and multiobject tracking and potential related mental factors including depression, anxiety, perceived stress, and social support were examined. Job performances were measured by both subjective and objective indicators, i.e., the overall evaluation by supervisors and the delay time by dispatching simulator. Stepwise regression results showed that both cognitive abilities and 2 mental factors (depression and perceived stress) have strong relations with job performance, and tremendous distinction between groups of good and poor performance of HSR dispatchers is revealed. The predictive model accounted for 91% of the overall variance in objective performance indicator and has 96% distinguished accuracy of good and poor groups. These findings imply that cognitive and mental factors should be of great concern to the current practice of Chinese HSR dispatcher selection and management., 1. Introduction With the share of China accounting for about 2/3 of the world high-speed railway (HSR) mileage [1], the daily transportation of China's high-speed trains is about 1.33 million, [...]

Objects intruding high-speed railway clearance do great threat to running trains. In order to improve accuracy of railway intrusion detection, an automatic multimodal registration and fusion algorithm for infrared and visible images with different field of views is presented. The ratio of the nearest to next nearest distance, geometric, similar triangle, and RANSAC constraints are used to refine the matching SURF feature points successively. Correct matching points are accumulated with multiframe to overcome the insufficient matching points in single image pair. After being registered, an improved Contourlet transform fusion algorithm combined with total variation and local region energy is proposed. Inverse Contourlet transform to low frequency subband coefficient fused with total variation model and high frequency subband coefficients fused with local region energy is used to reconstruct the fused image. The comparison to other 4 popular fusion methods shows that our algorithm has the best comprehensive performance for multimodal railway image fusion., 1. Introduction High-speed railway is a competitive transportation all over the world. As of 2017, the length of commercial high-speed railway lines in China had exceeded 25,000 km. With the [...]

Simultaneously considering train scheduling problem and maintenance planning problem with uncertain travel time, we propose a two-stage integrated optimization model for the sunset-departure and sunrise-arrival trains (SDSA-trains). Specifically, in the first stage, we obtain an optimal solution of the SDSA-trains under each scenario, which leads to the minimum total travel time. In the second stage, a robust SDSA-train schedule is generated based on the optimal solutions of the first stage. The key is that we consider two operation modes to solve the conflict between the SDSA-trains and the maintenances. Some state variables are used to deal with train operation mode selection. Furthermore, some linearization techniques are used to formulate a mixed-integer linear programming (MILP) model. Finally, numerical experiments are implemented to prove the effectiveness of the proposed model and optimization method., 1. Introduction Desirable train schedules are important to ensure the efficient operation of the high-speed railway system, but some uncertain events (e.g., bad weather conditions, equipment failure) often occur due [...]

In the forthcoming decades, railway transport is expected to face a significant growth of traffic flows which will mostly have to be accommodated over the existing infrastructures. An increase of [...]

Rail transport authorities around the world have been facing a significant challenge when predicting rail infrastructure maintenance work. With the restrictions on financial support, the rail transport authorities are in pursuit of improved modern methods, which can provide a precise prediction of rail maintenance timeframe. The expectation from such a method is to develop models to minimise the human error that is strongly related to manual prediction. Such models will help rail transport authorities in understanding how the track degradation occurs at different conditions (e.g., rail type, rail profile) over time. They need a well-structured technique to identify the precise time when rail tracks fail to minimise the maintenance cost/time. The rail track characteristics that have been collected over the years will be used in developing a degradation prediction model for rail tracks. Since these data have been collected in large volumes and the data collection is done both electronically and manually, it is possible to have some errors. Sometimes these errors make it impossible to use the data in prediction model development. An accurate model can play a key role in the estimation of the long-term behaviour of rail tracks. Accurate models can increase the efficiency of maintenance activities and decrease the cost of maintenance in long-term. In this research, a short review of rail track degradation prediction models has been discussed before estimating rail track degradation for the curves and straight sections of Melbourne tram track system using Adaptive Network-based Fuzzy Inference System (ANFIS) model. The results from the developed model show that it is capable of predicting the gauge values with [R.sup.2] of 0.6 and 0.78 for curves and straights, respectively., 1. Introduction Modern transport organizations have shifted their focus from construction and expansion of the transport infrastructure towards how to intelligently maintaining them. This has taken place due to many [...]

In this paper, the statistical distribution of railway track geometry data is investigated using a significant volume of field data. Analyzing the results yields a general pattern for the statistical distribution of the track geometry data. This is used to develop new indexes for track geometry parameters including gauge, profile, alignment, and twist. An overall track geometry index is established by combining the new parameter's indexes. This combination is made by assigning a coefficient to each geometry parameter based on its role in the overall quality condition of the track. In comparison with the approaches previously used for the development of the track geometry indexes, this method has three distinguishing features. First, the mean values along with the SD of data are incorporated into the calculation of the new indexes. Second, the new indexes indicate not only the condition of the individual parameters but also the overall track geometry condition. Third, the track classification is considered, and an index is developed for each class of the tracks. A practical use of the new indexes is presented and discussed in the paper. DOI: 10.1061/(ASCE)0733-947X(2010)136:8(693) CE Database subject headings: Geometry; Alignment; Railroad tracks; Statistics. Author keywords: Geometry index; Twist; Profile; Alignment; Gauge; Standard deviation; Mean.

Treatment selection bias leads to an inaccurate estimation of treatment effects as applied to specific sites or problem locations. Treatment selection bias is a major source of inconsistency in the results obtained from conventional before and after and cross-sectional models. One of the major expressions of treatment selection bias concerns the use of collision occurrence data in justifying intervention. For example, in highway safety field, a treatment is often introduced at a given site based on its high collision experience. Under normal conditions we would expect these collision numbers to return to a lower long term expected value, regardless of intervention. For treated sites, conventional observational models ascribe this reduction in collisions to the given treatment. This results in an overestimation of treatment effect. In this paper, a propensity score model is introduced that deals explicitly with treatment selection bias. The model is applied to Canadian highway--railway grade crossings data to estimate reductions in collision subject to upgrades in warning devices. The results of the propensity score model are compared for similar types of treatments to a number of before and after and cross-sectional models for both U.S. and Canadian data. The propensity score method is shown to reduce treatment selection bias and has probable merit that need to be further examined. DOI: 10.1061/(ASCE)0733-947X(2007)133:2(112) CE Database subject headings: Safety; Railroad grade crossings; Evaluation; Statistics.

Taipei Metro adopted the diode-grounded scheme for stray current collection in construction of its cross rail network. During operation of the network, a high rail-to-earth potential ([V.sub.rali]) has been observed at the east end of the Blue Line (i.e., stations BL13-BL16). To find effective countermeasures, a series of field tests in a step-by-step development nature was conducted from 1999-2000, which led to the decision of disconnecting the impedance bond at G11 of the tie line so that the negative return current of the Blue Line cannot flow to the rails of the Red-Green Line, and vice versa (detailed in Sections III-A and V-C). This decision was implemented through contract-out work in 2003. Since then, the Frail has been lowered by almost half before disconnection. To gain the insight characteristic before the contract-out, numerical simulations were also conducted by simulating the multi-train and multisection features of the cross transportation network. The simulation results (for [V.sub.rail] and stray current, or [I.sub.stray]) were consistent with the field-test results. This paper presents the design of these field tests and their test results in comparison with the simulation results, based on which the countermeasures for reducing [V.sub.rail] and the present status after Frail reduction at Taipei Metro are presented. Index Terms--DC transit railway, diode-grounded, field tests, multi-train simulation, rail-to-earth potential, stray current.

In the locomotive-scheduling problem (or the locomotive-assignment problem), we must assign a consist (a set of locomotives) to each train in a preplanned train schedule so as to provide each [...]

Train units need regular preventive maintenance. Given the train units that require maintenance in the forthcoming one to three days, the rolling stock schedule must be adjusted so that these [...]

Shippers decide to use particular transportation modes and carriers based at least partially on their perceptions of the services provided.(1) An example of this relating to intermodal rail-truck service was [...]