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891.
A survey of Bus Rapid Transit BRT and Bus of High Level of Service BHLS around the world indicates that there are about 120 cities with bus corridors, with 99 of the cities entering into the list in the last 12 years. The existing bus corridors comprise about 280 corridors, 4300 km, 6700 stations and use 30,000 buses, serving about 28 million passengers per day. In 2010–2011, 19 cities completed new systems − 16 in the developing world – and seven cities expanded their current systems. By late 2011, about 49 new cities were building systems, 16 cities were expanding their corridors, and 31 cities were in initial planning. This impressive growth may be attributed in part to the successes of Curitiba, Bogotá, México City, Istanbul, Ahmedabad and Guangzhou. These cities show low cost, rapid implementation and high performance BRTs, with significant positive externalities. Interesting trends are emerging, such as the implementation of citywide integrated bus systems, improved processes for private participation in operations, increased funding from national governments, and growth of bus manufacturers and technology providers. Despite the growth, there are some outstanding issues: BRT and BHLS do not have a single meaning and image and are often regarded as a “second best” as compared to rail alternatives. In addition several systems in the developing world suffer problems resulting from poor planning, implementation and operation, due to financial, institutional and regulatory constraints. The BRT and BHLS Industry are in their “infancy” and there is need for consolidation and concerted effort.  相似文献   
892.
This first part of the state-of-the art focuses on the origins of road safety modeling, covering data, early models and the public health context of model formulation and use.  相似文献   
893.
The third part of the state-of-the-art focuses on the future of road safety modeling and on conjectures concerning the evolution of national safety indicators. In the absence of econometric developments specific to road safety modeling, the research future must rely on pre-existing statistical procedures of econometrics applied to discrete/count and to aggregate data. In terms of contents, growing interest in the heterogeneity of road accident outcomes by category of victims could lead to treatments of this issue across research streams, say by top-down and bottom-up developments, but this speculation does not rest on extant adequate formulations of the issue of road user class and victim analysis. But understanding the time profile of aggregate national performance indicators is quite another matter.  相似文献   
894.
The emergence of Intelligent Transport Systems (ITS) has been recognised with many initiatives during the last 20 years. In Europe, the “ITS Action Plan” identifies a number of applications as key elements contributing to the efficient co-ordination of the overall transport chain. The context and experience surrounding the recent widespread development of technological tools and ICT platforms to support the emergence of ITS are notable for the way in which they permeate the transport and logistics chain. But a key question remains: to what extent is the public transport sector able to exploit the wider benefits of ITS?  相似文献   
895.
The paper presents the main characteristics, costs and impacts of TransMilenio, the bus based mass transit system of Bogotá, using BRT corridors and feeder services. An ex-post cost-benefit analysis is done, including monetary valuation of direct impacts on travel time and travel cost and externalities, such as improved road safety and air quality. Impacts on crime, land values, employment and tax revenue are also presented. The results are positive and robust; nevertheless, it is important to recognize that user perception has declined and there is urgent need to introduce service improvements. The paper also includes an ex-ante evaluation of the projected expansion using current costs, which indicates the need to limit construction capital costs. The results are an indication of the potential of BRT, and the evaluation methodology is applicable to other transit projects.  相似文献   
896.
This paper elaborates on the definitions of inter and multi-modal transport, as well as their differences in terms of performance. A survey of the barriers, both internal and external, to an efficient intermodal transport is included followed by an analysis of the advantages and disadvantages of combining rail transport with the other transport modes. Transhipment technologies for efficient freight service and some examples of freight rail corridors between sea and inland terminals are presented. The integration between air and rail transport is discussed and the potential synergies between air and high-speed rail services are emphasised. The paper concludes with a discussion on energy use for sustainable rail performance.  相似文献   
897.
The diagnosis for urban transport sustainability depends on the context of different regions worldwide. We focus in this paper on West and North Africa which reveal similarities but also structural differences which are explored further. The importance of paratransit in its various forms is strongly observed in sub-Saharan Africa and to a lesser extent in North Africa. The attempts to regulate and organise this sector have been difficult; one interesting experience in Dakar occurred during a programme of fleet renewal. In parallel it is observed that there are positive but insufficient experiences of public transport authorities in some cities (Dakar, Abidjan) and similar projects postponed in other cities because of the institutional problems. One also observes the constant difficulties of designing sustainable schemes for bus companies. An answer to this crisis has been found in North Africa, through investment in new mass transport systems. However, mass transport projects in West Africa are very weak in comparison. The gap between public transport costs and income levels there remains a major obstacle to sustainable mobility exacerbated by the poverty of a significant part of the urban population in West Africa. Two other critical factors are also identified affecting sustainable mobility requirements, namely, the urban sprawl and increasing energy costs. Finally the conclusion recommends the use of research and expertise networks in order to help the design and the implementation of suited solutions.  相似文献   
898.
证实了干散货运输是国际贸易的派生需求,并根据派生需求理论,建立了干散货市场与国际贸易过原点的回归模型.通过引用联合国统计数据,利用社会科学统计软件包(SPSS软件),计算获得国际贸易与干散货船舶运输需求的相关性系数.并根据该相关系数计算知,2012-2014年间,干散货市场的供给与需求之间存在较大缺口,即干散货市场的船舶供给过剩达到14%左右.到2014年之前,干散货市场很难消化已有的存量船舶.因而对于干散货市场的航运企业在未来几年的策略是“去产能”.  相似文献   
899.
与其他优化问题相比,多式联运网络路径优化问题面临着变量较多且其结构、关系复杂的困扰.然而,现有的多式联运网络只能对网络属性逐一计算,难免重复冗余,效率偏低,只适用于小型网络.提出了不规则棱柱网络模型.采用相对编码设计,通过搜索判断余子式进行网络初始化,将网络中不同类别的弧线解释成满足某种约束条件的量,通过设计底边判断函数和侧棱判断函数,实现了网络中弧线的智能分类.该模型取消了运输网络阶段划分的限制;其节点与现实运输的地理坐标相对应;分类判断可以对网络进行群体修建与更新.通过对比各网络的时间频度,说明在多属性变量复杂且多样性的大规模多式联运网络中,该网络能够极大地提升网络构建和更新效率.  相似文献   
900.
张洪达 《船舶》2013,24(2):1-6
多体船与同吨位单体船相比,前者可获得单位面积排水量时更大的甲板面积、良好的横稳性、优良的抗沉性和适航性。高速水运相对于其他运输方式而言,具有装载量大、营运成本低、初始投资少等显著优势。文中以某型具有特定滚装功能(可携带冷藏集装箱、汽车等)的三体客货运输船为例,详细介绍其主要技术参数、设计方案、材料和动力装置的选取情况,总结了三体船的受力特点,对同类型船设计中危险工况确定的强度分析和结构优化具有一定的指导意义。  相似文献   
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