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51.
In this paper, a case study is carried out in Hong Kong for demonstration of the Transport Information System (TIS) prototype. A traffic flow simulator (TFS) is presented to forecast the short‐term travel times that can be served as a predicted travel time database for the TIS in Hong Kong. In the TFS, a stochastic deviation coefficient is incorporated to simulate the minute‐by‐minute fluctuation of traffic flows within the peak hour period. The purposes of the case study are: 1) to show the applicability of the TFS for larger‐scale road network; and 2) to illustrate the short‐term forecasting of path travel times in practice. The results of the case study show that the TFS can be applied to real network effectively. The predicted travel times are compared with the observed travel times on the selected paths for an OD pair. The results show that the observed path travel times fall in the 90% confidence interval of the predicted path travel times.  相似文献   
52.
本文首先分析了MATLAB和VC++各自的编程优缺点;基于MATCOM转化法的VC++与MATLAB混合编程基本步骤;理想的汽车前、后轮制动器制动力分配曲线(I曲线)方程推导以及相关知识.然后重点介绍了如何利用MATCOM转化法实现I曲线的模拟绘制,并与理想的I曲线比较得出结论.  相似文献   
53.
为实时优化定制公交线路,提出一种基于可靠性最短路的线路优化方法,在复杂的交通环境中,可以高效的将乘客送达目的地. 对可靠性最短路进行问题描述,建立可靠性时空网络;给出求解可靠性最短路的算法步骤,构建乘客和定制公交运营商总成本最小的目标函数,采用禁忌搜索算法对问题进行求解;最后,以某市定制公交路网进行实例分析. 结果表明:与最短路线路方案比较,所提方法更接近于实际运营;在高峰时段,交通拥堵的情况下,所提方法可以提高车辆的可靠性,提升定制公交线路的服务水平.  相似文献   
54.
我国电气化铁路建设从普速发展到高速,就接触网系统来说,设计和施工技术经历了3个阶段的质量提升,上了3个台阶,为施工技术达到国际一流水平奠定了基础。这都是由符合工程特点的施工工法、工艺及作业指导书作保障实现的。但在此前几年的高速铁路接触网施工中了解到,各施工单位编写的或执行的施工工艺及作业指导书,其工程分类和应包括的项目及内容不但不统一,而且有较大的差别,以致造成施工质量和精度不能保持在一个较高的水平上。为此结合高速铁路接触网设计对其施工工艺及作业指导书进行进一步阐析。  相似文献   
55.
In contemporary times, Public–Private Partnership (PPP) in transport infrastructure has gained considerable attention in developing regions following its success in the developed countries. However, Sub-Saharan Africa (SSA) is among the developing regions with few transport PPP projects and among the regions with high number of failed projects. Meanwhile the region's transport infrastructure need far exceeds it current provision. This paper therefore aims to examine the project experiences (success and failure factors) of three highly profiled transport PPP projects, namely the Lekki toll road concession project (Nigeria), N4 toll road (South Africa/Mozambique) and Port of Maputo (Mozambique) in order to develop policy measures for effective future implementation. The experiences of the three projects show that transport PPP policy is indeed feasible in SSA. However, to realise its full applicability, proper policy actions and measures must be carefully observed and these include effective and efficient stakeholder management, transparent and competitive tendering process, high participation of local investors, stable macro-economic conditions and strong government commitment and regulatory framework. The projects experiences and policy actions developed are impactful in accelerating transport infrastructure development through PPP approach in SSA. Hence it is hoped that policy-makers and practitioners would be informed on the key strategies to employ in implementing future projects.  相似文献   
56.
基于非消防负荷在切除方式、时间、切断点等方面做法不一的问题,通过对各种非消防负荷的类型特点、断电影响、火灾位置、运营管理需求等方面进行分析,对不同的切除对象给出相应切除的方式、时间、切断点。提出优化后的切非方案:三级负荷等可立即切除的负荷和有固定控制流程的负荷均自动切除;无法固定控制流程的负荷手动切除。三级负荷等断电不会影响运营和疏散救援的负荷可立即切断;电梯、站台门、闸机/门禁按控制逻辑指令执行完可切除;切断点选在变电所低压柜内较安全,正常照明、小动力箱建议在配电箱处分区域切除。  相似文献   
57.
提出了通过增加安装调节参数来代替部分数控联动坐标,加工特种回转面刀具的方法,该方法减少了对机床的要求,又改善了加工条件和齿槽形状,只要用 3坐标联动的机床或数控装置便可加工出原本需5坐标甚至6坐标数控才能加工的刀具。  相似文献   
58.
公共交通是城市道路交通运输系统中的重要组成部分,公交车驾驶人存在的不良驾驶行为已经成为影响交通安全的最大制约因素之一,由其引发的道路交通事故给个人和社会都造成了严重损失,探索更为安全的公共交通环境显得极为重要。以公交车驾驶人为对象,探究影响公交车驾驶人驾驶行为特征的个人心理因素和组织环境因素,及其对不良驾驶行为的内在影响机制。选用工作倦怠量表(MBI-GS)、组织认同感问卷(OIQ)及驾驶行为问卷(DBQ)对844名城市公交车驾驶人展开问卷调查研究,并使用回归分析和中介检验来探究工作倦怠和组织认同感对驾驶行为的影响机制。结果表明:①32.8%的公交车驾驶人存在不良驾驶行为,错误驾驶行为显著高于违法驾驶行为。其中,在违法维度中,侵略性违法显著高于普通违法。②公交车驾驶人存在较高的组织认同感,组织认同感对不良驾驶行为具有显著的负向预测作用,对工作倦怠程度具有显著的负向预测作用;工作倦怠程度对不良驾驶行为具有显著的正向预测作用。③公交车驾驶人的工作倦怠水平在组织认同感对不良驾驶行为的影响中起到部分中介作用。该结果厘清了公交车驾驶人的工作倦怠和组织认同感对不良驾驶行为的影响机制,为进一步探究不良驾驶行为的心理干预方法提供了思路,从而达到改善城市道路公共交通安全环境的目标。  相似文献   
59.
通过对津滨高速公路的调研,根据2009年检测的路面弯沉资料、路面结构层钻心成果和实地考察,对路面结构的改造制定出一套方案,并提出一种计算旧路补强时旧路路面计算弯沉值的方法。  相似文献   
60.
Since the late 1990s, numerous ridematching programmes have integrated the Internet, mobile phones, and social networking into their services. Online ridematching systems are employing a range of new strategies to create “critical mass”: (1) regional and large employer partnerships, (2) financial incentives, (3) social networking to younger populations, and (4) real-time ridematching services that employ “smartphones” and automated ridematching software. Enhanced casual carpooling approaches, which focus on “meeting places”, are also being explored. Today, ridesharing represents approximately 8–11% of the transportation modal share in Canada and the USA, respectively. There are approximately 638 ridematching programmes in North America. Ridesharing's evolution can be categorized into five phases: (1) World War II car-sharing (or carpooling) clubs; (2) major responses to the 1970s energy crises; (3) early organized ridesharing schemes; (4) reliable ridesharing systems; and (5) technology-enabled ridematching. While ridesharing's future growth and direction are uncertain, the next decade is likely to include greater interoperability among services, technology integration, and stronger policy support. In light of growing concerns about climate change, congestion, and oil dependency, more research is needed to better understand ridesharing's impacts on infrastructure, congestion, and energy/emissions.  相似文献   
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