Rapid,robust, distributed evaluation and control of train scheduling on a single line track

The technology for controlling the distance between two trains is shifting from traditional fixed red, yellow and green signals on the infrastructure track circuits towards more and more dynamic systems, which are based on moving blocks, where the distance is computed according to real-time positioning, and the control of the distance is computed on-line. This is the case, for example, in the European Rail Traffic Management System (ERTMS), which proposes three different levels, from 1 to 3. This paper addresses the time-honoured problem of scheduling trains on a single track, in the light of recent results in robust team decision theory. The control model can be used in two modes: as a decision support tool for train dispatchers to evaluate the distance between trains in the current schedule, and as a planning tool to evaluate the effects of timetable changes. The main contribution of the paper is the application of a recent result in robust team decision theory to control noncritical train distances in moving blocks, such as in ERTMS Level 3. The case study is related to real data from an ERTMS simulation and controller software tool.     

Two-station single-track railway scheduling problem with trains of equal speed

In this paper, the single-track railway scheduling problem with two stations and several segments of the track is considered. Two subsets of trains are given, where trains from the first subset go from the first station to the second station, and trains from the second subset go in the opposite direction. The speed of trains over each segment is the same. A polynomial time reduction from the problem under consideration to a special case of the single-machine equal-processing-time scheduling problem with setup times is presented. Different polynomial time algorithms are developed for special cases with divers objective functions under various constraints. Moreover, several theoretical results which can be ranked in a series of similar investigations of NP-hardness of equal-processing-time single-machine scheduling problems without precedence relations are obtained.     

不同型砧下列车轴锻件数值模拟研究

车轴倒棱滚圆过程中,合理的砧型结构对于保证锻件质量有重要作用。本文以DEFORM软件为平台,分别利用圆弧砧、平砧两种砧型对方坯倒棱滚圆进行三维数值模拟,比较两种砧型下火车轴倒棱滚圆成形后的尺寸精度和锻件内部应力应变状态;模拟结果表明:圆弧砧倒棱过程中,压下率大于10%后,心部压应力逐渐增大,平砧心部拉应力一直存在;滚圆结束后采用圆弧砧的锻件心部等效应变大于平砧33.3%;从滚圆精度方面分析,圆弧砧滚圆后圆周上测试点方差小于平砧测试点方差,并且平砧滚圆后的锻件平均直径大于理想值1%。说明圆弧砧倒棱滚圆可以得到成形质量和力学性能、精度最佳的火车轴。     

基于以太网的列车通信网络性能仿真研究

给出了一种基于工业以太网的列车通信网络体系结构。在对实际列车业务流量进行建模的基础上,利用网络仿真软件OPNET建立了以太网列车通信网络仿真模型,研究了车载工业以太网在进行大容量信息传输过程中的以太网时延、网络载荷、丢包率及以太网的极限流量等关键性能。仿真结果表明：通过合理设置网络参数,以太网可以满足列车通信网络对带宽和数据传输时延的要求,将以太网用于高速列车网络系统具有充分的可行性。     

Psychological factors for driver distraction and inattention in the Australian and New Zealand rail industry

A signal passed at danger (SPAD) event occurs when a train moves past a stop signal into a section of unauthorised track. SPAD events are frequently attributed to driver distraction and inattention, but few studies have explored the failure mode from the perspective of task demand and the ability of the driver to self-regulate in response to competing activities. This study aimed to provide a more informed understanding of distraction, inattention and SPAD-risk in the passenger rail task. The research approach combined focus groups with a generative task designed to stimulate situational insight. Twenty-eight train drivers participated from 8 different rail operators in Australia and New Zealand. Data were analysed thematically and revealed several moderating factors for driver distraction. Time-keeping pressure and certain aspects of the driver-controller dynamic were considered to distort performance, and distractions from station dwelling and novel events increased SPAD-risk. The results are conceptualised in a succinct model of distraction linking multiple factors with mechanisms that induced the attentional shift. The commonalities and inter-dynamics of the factors revealed insight into driving anxiety in the passenger rail mode, and suggested that SPAD-risk was intensified when three or more factors converged. The paper discusses these issues in the context of misappropriated attention, taxonomic implications, and directions for future research.     

捷达王配气机构维修

本文概述了捷达王用EA113型发动机配气机构的构造，详述了其拆卸和维修方法。     

高速磁浮列车磁场测量系统的设计

高速磁浮列车磁场主要分布在列车和轨道之间很小的空气隙中,气隙磁场是一个恒定磁场和交变磁场的叠加磁场,而且磁感应强度很大,最大可达1．2T．针对高速磁浮列车磁场分布的特殊性,设计了一套两自由度磁场的闭环自动化测量系统。系统的设计基于PC机,可以实现对列车磁场中的固定点和一段距离上的磁场大小的自动化测量,并将测量数据存入数据库以便于进一步处理分析。在列车实验平台磁场的实际测量中,该系统性能稳定,测量范围可达0～1．5T．     

Improved modelling of trains braking under low adhesion conditions

ABSTRACT

Predicting the behaviour of trains when braking under low adhesion conditions presents considerable challenges. This paper describes an approach to the problem using a model of the full train braking system known as LABRADOR (Low Adhesion Braking Dynamic Optimization for Rolling Stock) and an improved method for representing the creep force–creepage behaviour when low adhesion is presently known as WILAC (Water Induced Low Adhesion Creep Force Model). The development of these models and their integration are summarized and a number of test cases are presented to demonstrate the improvements which can be gained from this approach. A number of suggestions are made for future enhancements with the aim of providing brake engineers and systems integrators with reliable simulation tools for optimizing train braking performance when low adhesion is present.     

25型客车车体参数化仿真系统开发与应用

为提高25型铁路客车车体有限元模型前处理效率,通过25型铁路客车车体结构谱系梳理,采用模块化和参数化建模技术构建了25型客车车体模型库;基于HyperMesh软件开发了25型客车车体仿真模板;通过集成25型客车车体模型库和仿真模板开发了25型客车车体参数化仿真系统。该系统可通过模块选配和参数变更快速生成25型客车车体几何模型,通过调用仿真模板快速生成ANSYS和ABAQUS两种求解器所需的有限元模型。应用该系统使25型客车车体有限元模型前处理时间缩短为1周左右,极大提高了有限元模型前处理效率。