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901.
902.
《铁道标准设计通讯》2017,(9):128-132
车载人机界面(DMI)是目前列车自动防护系统(ATP)车载设备的重要组成部分,是唯一能实现列车司机与车载设备间二者交互的通道,所以其必须和用户有着很好的适应性,因此研究设计出高效稳定的人机界面有着非常重要的现实意义。基于软件的正向设计,从人机界面的功能需求出发,建立人机界面的基本模型框架,并疏理人机交互时序。最后使用Qt跨平台软件按其分层顺序依据各模块的功能流程图进行通用化的设计。 相似文献
903.
Morning commuters may have to depart from home earlier to secure a parking space when parking supply in the city center is insufficient. Recent studies show that parking reservations can reduce highway congestion and deadweight loss of parking competition simultaneously. This study develops a novel tradable parking permit scheme to realize or implement parking reservations when commuters are either homogeneous or heterogeneous in their values of time. It is found that an expirable parking permit scheme with an infinite number of steps, i.e., the ideal-scheme, is superior to a time-varying pricing scheme in the sense that designing a permit scheme does not require commuters’ value of time information and the performance of the scheme is robust to the variation of commuters’ value of time. Although it is impractical to implement the ideal-scheme with an infinite number of steps, the efficiency loss of a permit scheme with finite steps can be bounded in both cases of homogeneous and heterogeneous commuters. Moreover, considering the permit scheme may lead to an undesirable benefit distribution among commuters, we propose an equal cost-reduction distribution of parking permits where auto commuters with higher value of time will receive fewer permits. 相似文献
904.
Bernard P. Feeney 《运输规划与技术》2013,36(4):229-244
This paper reviews the empirical evidence relating to the impact of parking policy measures on the demand for parking and for travel. Disaggregate modal choice models, disaggregate parking location models and site‐specific studies of parking behaviour are examined. With regard to modal choice models, it is concluded that few studies deal adequately with parking factors, but that there is some support for the view that parking policy measures are a relatively important influence on modal choice. When parking location models are examined parking policy variables are shown to have a substantial impact on choice of parking location. With regard to site‐specific studies, the paper concludes that there is a great variation in the parking price elasticities quoted, which reflects partly the methodological problems associated with such studies. Suggestions to improve model specification are made. 相似文献
905.
Liang Ling David P. Thambiratnam 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(4):638-657
Derailments on bridges, although not frequent, when occurs due to a complex dynamic interaction of the train–track–bridge structural system, are very severe. Furthermore, the forced vibration induced by the post-derailment impacts can toss out the derailed wagons from the bridge deck with severe consequences to the traffic underneath and the safety of the occupants of the wagons. This paper presents a study of the train–track–bridge interaction during a heavy freight train crossing a concrete box girder bridge from a normal operation to a derailed state. A numerical model that considers the bridge vibration, train–track interaction and the train post-derailment behaviour is formulated based on a coupled finite-element – multi-body dynamics (FE-MBD) theory. The model is applied to predict the post-derailment behaviour of a freight train composed of one locomotive and several wagons, as well as the dynamic response of a straight single-span simply supported bridge containing ballast track subjected to derailment impacts. For this purpose, a typical derailment scenario of a heavy freight train passing over a severe track geometry defect is introduced. The dynamic derailment behaviour of the heavy freight train and the dynamic responses of the rail bridge are illustrated through numerical examples. The results exhibit the potential for tossing out of the derailed trains from the unstable increase in the yaw angle signature and a lower rate of increase of the bridge deck bending moment compared to the increase in the static axle load of the derailed wheelset. 相似文献
906.
907.
地铁公司在编制列车开行方案时,很难同时兼顾到公司自身利益与社会利益。因此,建立基于地铁公司效益和乘客满意度最大化的地铁列车调度方案优化模型非常必要。使用层次分析法计算不同影响因素的权重,利用模糊数学的方法对计算数据进行拟合,并通过实例验证该模型的可行性。 相似文献
908.
车辆的持续增长给城市尤其是大城市带来严峻的负外部影响:交通拥堵与尾气污染,而尾气污染正是霾形成的重要因素。日益严重的"堵"和"霾"迫使城市治理者必须面对和解决不断增长的车辆需求与稀缺的城市交通资源这一矛盾。基于经济学视角,从车辆(保有、出行)与停车位完全互补关系出发,构建停车费价格模型与"停车费——车辆成本"联动效应分析,通过停车费影响消费者保有及出行车辆的成本,间接影响消费者的购车意愿和车辆出行意愿,从而达到有效控制车辆增长、削减其使用量,促进城市交通资源优化配置的目的。最后从加快公车产权改革、建立动态的停车费价格调整制度、实行差异化停车费政策、优化公交系统以及适当限制车位供应等方面得出城市治理者运用停车费价格机制提高城市交通运行效率的政策启示。 相似文献
909.
列车区间运行和车站作业缓冲时间的设置在提高列车准时性的同时会降低时效性,本文兼顾旅客对时效性和准时性的要求,建立缓冲时间设置评价指标体系,提出均衡分布、逐渐增加和最后集中三种设置方案。以广深城际为例,对三种方案的仿真结果进行评价分析,得出每列车总缓冲时间取6 min,采用逐渐增加设置方案最优的结论。 相似文献
910.
环保、安全是交通运输领域备受关注的两大重要问题,智能交通系统(ITS)是解决这两大问题的一种有效方法。公路列车(Road Train)系统作为车用自组织网络(VANETs)在ITS领域的一个特殊应用,通过车车协同,整个公路列车队中,除头车由驾驶员驾驶,其他车辆都受头车发送的控制数据控制其自动驾驶。该系统集成了微电子技术、网络通信技术、多传感器集成技术以及车辆自动控制技术,旨在提高交通运输的安全性以及减少其所带来的环境污染,同时增加驾驶舒适性,其核心思想是通过车车通信的方式实现车辆之间的列队协同列队行驶。首先介绍了公路列车系统的概念,分析了公路列车系统的优点,提出了公路列车系统的体系框架结构,深入讨论了公路列车系统中所包含的关键技术,最后对公路列车系统进行了总结。 相似文献