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961.
城市轨道交通中小半径大坡道高架桥上无缝线路优化设计 总被引:1,自引:1,他引:0
减小轨道、桥梁受力,防止轨道因爬行而积聚纵向力,是城市轨道交通中小半径大坡道高架桥地段无缝线路设计的技术关键。以南京地铁南北线一期工程中半径R=350 m曲线地段的安德门和东井亭高架桥以及33‰大坡道地段无缝线路为例,研究实现优化设计的关键技术。利用在道岔的岔道与曲线头之间的直线段,增设一组单向钢轨伸缩调节器,避免道岔承受无缝线路的纵向力,同时也减小高架桥的墩台受力。对于小半径线路,调整锁定轨温,用最大温度拉力取代断轨力,用温度力的侧向分力和列车通过桥梁时的离心力叠加检算墩台受力。对于大坡道地段,采用控制爬行量或钢轨应力,确保运营安全。 相似文献
962.
Preparing highway emissions inventories for urban scale modeling: A case study in Philadelphia 总被引:1,自引:0,他引:1
R. Cook J.S. Touma A. Beidler M. Strum 《Transportation Research Part D: Transport and Environment》2006,11(6):396-407
Highway emissions represent a major source of many pollutants. Use of local data to model these emissions can have a large impact on the magnitude and distribution of emissions predicted and can significantly improve the accuracy of local scale air quality modeling assessments. This paper provides a comparison of top–down and bottom–up approaches for developing emission inventories for modeling in one urban area, Philadelphia, in calendar year 1999. A bottom–up approach relies on combining motor vehicle emission factors and vehicle activity data from a travel demand model estimated at the road link level to generate hourly emissions data. This approach can result in better estimates of levels and spatial distribution of on-road motor vehicle emissions than a top–down approach that relies on more aggregated information and default modeling inputs. 相似文献
963.
介绍了通过改变牵引杆和抗蛇行减振器橡胶节点的刚度及安装位置,达到降低车体弯曲振动的方法,有效地提高了车辆的运行舒适度. 相似文献
964.
分析了现代战争中的发展动态及现状,在此基础上提出了未来数据链的发展方向及主要技术特点,并结合综合性飞行任务的功能要求提出了系统的功能原理框图。 相似文献
965.
作者首先提出了城市交通系统应在协调中动态发展的观点,并在此基础上分析了城市交通系统发展的主要协调问题,根据文中城市交通系统的协调发展目标,对我国城市交通系统发展过程中急需解决的几类重要协调问题的协调对策提出了建议。 相似文献
966.
采用停车视距原理,阐述了机动车绿灯间隔时间在信号控制交叉口的作用,提出了机动车绿灯间隔时间的计算方法,并通过1个简单算例进行说明。最后,给出了绿灯间隔时间在黄灯和全红之间的分配方式。 相似文献
967.
通过研究山区高速公路隧道洞口桥隧相连的有关技术及其在实际工程中的合理选择与应用,分析其优缺点,并总结经验.对类似条件下桥梁与隧道的建设具有一定的指导意义。 相似文献
968.
This paper reports the results of a stated-preference study aimed at investigating how transport decisions are made by receivers
or by transport operators about the potential use of an urban freight consolidation centre in the city of Fano, Italy. Because
there are no revealed preference data, a stated-choice methodology is used. The stated-choice experiments present two alternatives—one
using a private vehicle subject to various traffic regulations and one using the urban freight consolidation centre with varying
cost and efficiency levels. Conventional discrete choice data modelling shows that the potential demand is influenced mainly
by the distance of the parking bay from the shop, by access permit cost, by the service cost of the urban freight consolidation
centre, and by the delay in delivery time. Simulations are then performed to assess how the potential demand is affected by
various incentives and regulations affecting urban goods distribution.
Edoardo Marcucci is Associate Professor of Applied Economics at the Faculty of Political Sciences, University of Roma Tre, Italy, General Secretary of the Italian Society of Transportation Economists, and co-founder of the Kuhmo—Nectar Conference and Summer School Series on Pricing, Financing, Regulating Transport Infrastructures and Services. He has studied freight transportation concentrating on interactions along logistic supply chains. Romeo Danielis is Full Professor at the University of Trieste, Italy. He is managing editor of European Transport\Trasporti Europei. He has published articles on input-output modelling, regional environmental policy, social costing of transport externalities, EU enlargement and on several transport issues including road pricing, the Down-Thompson paradox, energy use and CO2 emissions, freight transport demand and stated preferences. 相似文献
Edoardo MarcucciEmail: |
Edoardo Marcucci is Associate Professor of Applied Economics at the Faculty of Political Sciences, University of Roma Tre, Italy, General Secretary of the Italian Society of Transportation Economists, and co-founder of the Kuhmo—Nectar Conference and Summer School Series on Pricing, Financing, Regulating Transport Infrastructures and Services. He has studied freight transportation concentrating on interactions along logistic supply chains. Romeo Danielis is Full Professor at the University of Trieste, Italy. He is managing editor of European Transport\Trasporti Europei. He has published articles on input-output modelling, regional environmental policy, social costing of transport externalities, EU enlargement and on several transport issues including road pricing, the Down-Thompson paradox, energy use and CO2 emissions, freight transport demand and stated preferences. 相似文献
969.
随着北京、上海、广州等大城市轨道交通和BRT的兴起,产生了很多新的问题,其中如何协调轨道交通与BRT线网规划成为城市交通规划的重点。本文在进行城市轨道交通和BRT特性比较和功能定位的基础上,分析了城市轨道交通与BRT线网规划协调的涵义、重要性和研究内容,并对两者线网规划协调方案评价进行了研究,建立了评价指标体系。提出了要处理好线网规划协调影响因素、不同城市应根据自身特点选择不同的交通发展方式、面向城市公交一体化的综合交通规划、建立有效的公共参与机制四点结论。 相似文献
970.
城市客运交通结构的影响因素研究 总被引:2,自引:0,他引:2
在分析交通结构组成和基本模式的基础上,归纳总结了城市客运交通结构存在的问题。对影响城市客运交通结构的主要因素进行了定性研究,为城市客运交通结构向合理化方向发展提供借鉴。 相似文献