Delay Restoration of Single-Track Railway Rescheduling

On the basis of analysis of the principle of delay restoration in a disturbed schedule, a heuristic algorithm for rescheduling trains is developed by restoring the total delay of the disturbed schedule. A discrete event topologic model is derived from the original undisturbed train diagram and a back propagation analysis method is used to label the maximum buffer time of each point in the model. In order to analyze the principle of delay restoration, the concept of critical delay is developed from the labeled maximum buffer time. The critical delay is the critical point of successful delay restoration. All the disturbed trains are classified into the strong-delayed trains and the weak-delayed trains by the criterion of the critical delay. Only the latter, in which actual delay is less than its critical delay, can be adjusted to a normal running state during time horizon considered. The heuristic algorithm is used to restore all the disturbed trains according to their critical details. The cores of the algorithm are the iterative repair technique and two repair methods for the two kinds of trains. The algorithm searches iteratively the space of possible conflicts caused by disturbed trains using an earfiest-delay-first heuristics and always attempts to repair the earliest constraint violation. The algorithm adjusts the weak-delayed trains directly back to the normal running state using the buffer time of the original train diagram. For the strong-delayed trains,the algorithm uses an utility function with some weighted attributes to determine the dynamic priority of the trains, and resolves the conflict according to the calculated dynamic priority. In the end, the experimental results show that the algorithm produces ＂good enough＂ schedules effectively and efficiently in disturbed situations.     

T型梁砼的振捣工艺

通过施工实践，结合理论学习，就保证T梁质量的关键工艺振捣进行了介绍，并就振捣注意事项、方法、原则和经验进行了阐述。     

时间周期耗散结构的定性分析及应用

三分子模型的时间周期耗散结构在无扩散和有扩散时分别呈现浓度振荡与波样行为；通过Ｌｏｔｋａ－Ｖｏｌｔｅｒｒａ模型和ｓｃｈｌｏｇｌ模型的应用，可以对自然规律加以发现。这一原理可称为时间周期耗散结构。此原理可用于竞争预测。     

离心式水泵旋转叶栅流动显示试验

介绍了一种定性观测离心式水泵旋转叶栅流动的方法，方法简易。无需高精设备，只要采用普通相机及闪光灯，就能获得预期效果。     

船用冷库新型压缩——喷射制冷循环的实验研究

此文阐述了自行研制的船舶冷库新型压缩－－喷射制冷循环实验装置组成及其设计要点，并用该实验系统与原循环系统进行了对比实验，用实验数据验证了新型压缩－－喷射制冷循环的压缩机工作性能、单位制冷量、单位容积制冷量、制冷系统等都有较大程度的提高，为进一步在实船上应用提供参考。     

建设世界一流高原铁路--记刘志军部长、孙永福副部长赴青藏铁路现场办公

建设世界一流高原铁路的具体目标：把全线旅客列车旅行时间压缩到最短；全线设备达到“免维修”要求；沿线基本实现“无人化”管理。     

世界银行贷款项目“卫津路拓宽工程”的经济效益计算

本市以天津城市主干道卫津路拓宽改造工程为例，论述城市道路经济效益计算方法。按全天高峰小时、非高峰小时，分别计算机动车和非机动车的运营成本、时间价值及事故费用，采用有、无项目对比法．进行经济效益计算。经济效益中以车辆行程时间延误与路口时间延误的节约作为主要效益。     

货车中转时间的灰关联分析

针对铁路运输生产管理实际，应用系统工程理论详细分析了铁路货车中转时间的组成，用灰色理论关联度分析法定量分析铁路货车中转时间延长或缩短的诸多因素，为综合各种因素对货车中时的影响，对货车中时与有调车中转时间，无调车中转时间的关联度进行研究，提出了计算货车中时的关联模型，用此方法分析了一个实例，计算结果表明：货车中时与有调车中转时间关联度大，压缩货车中时的重点是有调中时，特别是各种非生产等待时间，该方法对问题的分析能抓住核心和关键，且计算方法简便，有利于车站对运输生产活动进行客观分析，可据以总结经验，改进工作，提高运输组织管理水平。     

2月中国轨道交通大事及点评

铁路突击抢运电煤告捷10天增运电煤超千万吨；北京地铁2号线奥运会前将使用新信号系统；新疆首条电气化铁路今年有望提前贯通；南京地铁元宵节加开16趟列车；铁路首次出现双向流动热潮