A schedule‐based dynamic transit network model — Recent advances and prospective future research

Using the schedule‐based approach, in which scheduled timetables are used to describe the movement of vehicles, a dynamic transit assignment model is formulated. Passengers are assumed to travel on a path with minimum generalized cost that consists of four components: in‐vehicle time; waiting time; walking time; and a time penalty for each line change. A specially developed branch and bound algorithm is used to generate the time‐dependent minimum path. The assignment procedure is conducted over a period in which both passenger demand and train headway are varying. This paper presents an overview of the research that has been carried out by the authors to develop the schedule‐based transit assignment model, and offers perspectives for future research.     

液压停车器系统的改进

针对YT-2C型液压停车器存在液压系统漏油、电机易烧毁、支撑头易断裂、油封损坏快等问题,对油缸、蓄能器、油泵电机组、支撑头、油封等进行了技术改进。改进后的设备性能稳定,满足了现场使用要求。     

活性粉末混凝土(RPC)在铁路预制梁工程中的应用

活性粉末混凝土是一种新型超高强水泥基复合材料.它具有超高的力学性质,优异的耐久性、较低的收缩和徐变性能.本文结合工程实例介绍了RPC混凝土在铁路预制梁工程中的成功应用,对今后其它工程领域应用RPC混凝土有一定借鉴意义.     

Analysis of Numerical Results in High Temperature Congealment and Chemistry Non-equilibrium Flow Field

Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved. In this paper, using internalequivalent heat area in place of electric are that created Ohm heat, the flow fields of thermodynamic equilibrium chemistry con-gealment and chemistry non-equilibrium in the plasma generator were simulated. The influences of the inlet prerotation angleof air, the inlet total pressure of air and the airflow compression angle of spray nozzle on the temperature on the surface of elec-     

Automatic Steering Based on Roadway Markers: From Highway Driving to Precision Docking

Bus Rapid Transit (BRT) is an effective alternative for providing rail-like corridor transit service. An advanced BRT concept involves the use of automated buses to provide functions of a rail transit system. A vehicle under automatic steering control following a prescribed trajectory is operated like a train on a rail. A lateral position sensing that uses roadway markers, such as magnetic markers embedded under the roadway, as lateral reference is one of the promising approaches for a reliable sensing system. The BRT concept requires the steering control system to consistently perform all necessary steering functions from high speed driving to low speed precision docking. This paper describes a single steering controller that achieves all performance objectives. Various data collected during several public demonstrations are presented in this paper to illustrate the effectiveness of the approach. These data include the following automatic steering control scenarios: over 100 mph high-speed driving, high-g maneuvers, sharp curve following, and low speed precision docking.     

视频分析技术综述及铁路应用初探

视频分析技术作为智能视频监控系统的核心技术,正越来越广泛地应用于中国铁路通信系统之中,为铁路安全的监控提供了一种先进可靠的技术手段。本文介绍了视频分析技术的起源、发展和基本实现原理,分析了国内外视频分析的应用现状和铁路市场未来的应用。     

基于铸铝工艺的悬架下控制臂可变壁厚优化设计

以采用铸铝工艺成型的汽车悬架下控制臂为研究对象,基于Opti Struct尺寸优化与CATIA曲面建构方法,开展可变壁厚悬架下控制臂的优化设计,并通过仿真分析与实车试验验证方案的可行性与可靠性,实现下控制臂的轻量化设计。本文提出的可变壁厚优化设计方法可为汽车其它零部件的轻量化设计提供参考。     

浅埋偏压膨胀土隧道大管棚预加固效果分析

针对小河沟膨胀性黄土铁路隧道浅埋偏压段大管棚施工工艺,分析了大管棚的受力状态和对围岩的加固效果。利用快速拉格朗日限差分软件FLAC3D模拟隧道管棚施工,得到各工况下管棚与管棚注浆壳体的受力变形情况和掌子面前方围岩变形位移,将所得结果与无管棚支护时的围岩变形位移比较,分析研究管棚预支护效果。试验分析表明,管棚有效抑制了掌子面前方软弱围岩的塑性流动,增强了围岩稳定性。     

一种集成多点位限位功能的车门铰链设计

常见的车门铰链和车门限位器都是安装在车门的不同位置上,本文所介绍的自带多级限位功能的车门铰链将车门的旋转和限位两个功能整合到一起,同时具有多点位的限位功能。该机构的设计既节省了空间,也简化了安装调试工序,非常适合于卡车车门,客车、校车应急门商用车辆。     

1200 TEU双燃料集装箱船设计

为探索双燃料船舶的设计特点,阐述了1 200 TEU双燃料集装箱船的总体设计特点,详细论述了主尺度选择、线型优化、重量控制、结构轻量化设计和双燃料动力系统的设计.重点研究了LNG燃料围护系统及其关键技术要点,尤其是C型独立燃料罐及连接处的设计和布置.在此基础上,完成了一种双燃料船型的基本设计方案,为以后设计此类船型提供参考.