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31.
This paper proposes a new dynamic bus control strategy aimed at reducing the negative effects of time-headway variations on route performance, based on real-time bus tracking data at stops. In routes with high demand, any delay of a single vehicle ends up causing an unstable motion of buses and producing the bus bunching phenomena. This strategy controls the cruising speed of buses and considers the extension of the green phase of traffic lights at intersections, when a bus is significantly delayed. The performance of this strategy will be compared to the current static operation technique based on the provision of slack times at holding points. An operational model is presented in order to estimate the effects of each controlling strategy, taking into account the vehicle capacity constraint. Control strategies are assessed in terms of passenger total travel time, operating cost as well as on the coefficient of headway variation. The effects of controlling strategies are tested in an idealized bus route under different operational settings and in the bus route of highest demand in Barcelona by simulation. The results show that the proposed dynamic controlling strategy reduces total system cost (user and agency) by 15–40% as well as the coefficient of headway variation 53–78% regarding the uncontrolled case, providing a bus performance similar to the expected when time disturbance is not presented. 相似文献
32.
海外总承包项目勘察设计工作特点及策略 总被引:1,自引:0,他引:1
介绍了海外总承包项目勘察设计工作特点,分析了国内设计企业在承担海外项目勘察设计过程中存在的主要问题,就如何更新设计理念、重视策划沟通、加强设计管理、提高设计质量、培养人才队伍、培育当地化勘察力量提出了建议意见,简要探讨了加强与海外咨询公司合作、推动中国标准走向世界等问题。对海外项目勘察设计工作有借鉴意义。 相似文献
33.
基于攻击策略的城市轨道交通网络脆弱性研究 总被引:1,自引:0,他引:1
城市轨道交通网络脆弱性评估是当前网络研究中新的热点和难点。识别并量化网络脆弱性是应对城市轨道交通系统危机状况的关键性课题。根据北京地铁网络结构,结合城市轨道交通实际运营特点,构建了网络换乘模型。从线路与换乘通道重要度两个视角,采用不同攻击策略研究并量化了网络脆弱性。研究结果表明:采用网络有效性与网络连通度作为网络脆弱性的衡量指标,并把攻击前后的重要节点(边)网络特征值下降程度作为网络脆弱性衡量标准的评估方法简便易行,具有一定的理论与应用价值。 相似文献
34.
智能低压配电系统在地铁中的应用 总被引:1,自引:1,他引:1
朱江 《城市轨道交通研究》2009,12(9)
根据地铁低压配电系统的特点,结合当前智能低压系统的广泛应用,提出了地铁智能低压的基本组成、功能要求、实现方法以及发展方向.智能化低压系统总的发展趋势是智能化、网络化、组合化、模块化、高性能和小型化,并将电力、电子、计算机、信息神经网络及模糊控制等相关的高新技术有机结合,提高整个配电系统的可靠性. 相似文献
35.
36.
A variety of barriers to listening comprehension are illustrated in this paper. They are analyzed respectively and several effective strategies are also presented afterward. The barriers to listening are those of psychological quality, language knowledge, cultural background, Chinese interference and so on. The strategies should be as follows: training students' psychological quality, strengthening the teaching and learning of language knowledge, comparing cultural differences, using student-centered teaching method and combining intensive listening and extensive listening. 相似文献
37.
The transportation fare system influences the mobility of a region and the life quality of its inhabitants. This study aims to evaluate a region's optimal fare system by using the analytic hierarchy process, based on a survey among transportation experts, divided into three categories: operators, professors/consultants and government officials. The results are presented divided by category and overall, and the performance of the most important relative criteria to establish a fare system is determined. The most important criterion according to all the selected experts was the fare price, with 21.5%. The fare system determined as the best was distance/zone (31.1%) and the worst was a flat fare system (7.2%). In addition, we show the influence of the fare price criterion in each fare system through sensitivity charts and highlight its importance for all three groups of experts to evaluate the fare system. 相似文献
38.
39.
AT供电方式是我国高速和重载电气化铁道普遍采用的一种供电方式,其故障测距问题一直是研究的热点和难点。针对AT供电方式的特点,提出了基于支持向量机的AT供电牵引网故障测距方法,仿真结果证明了该方法的有效性。 相似文献
40.
基于有限理性的顾客满意及其对策研究 总被引:3,自引:0,他引:3
顾客满意是提高企业竞争力的重要措施。在综述了国内外有关顾客满意理论研究的基础上,讨论了基于有限理性的顾客和顾客满意的本质含义;然后建立了多变量顾客满意的模型,辨析了构成顾客满意模型的多变量之间的关系。最后,从企业形象战略的再塑、全面顾客满意、可视化柔性决策和客户关系管理4个方面对顾客满意的对策进行了研究。 相似文献