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71.
Abstract

Public transport policy in the Madrid Metropolitan Area is often deemed as a success. In 1985, an important reform was carried out in order to create a new administrative authority to coordinate all public transport modes and establish a single fare for all of them. This reform prompted a huge growth in public transport usage, even though it reduced the funding coverage ratio of the transport system. Since then, Madrid’s public transport system has been undergoing an increasing level of subsidization, which might jeopardize the financial viability of the city public transport system in the future. In this paper, we present a detailed analysis of the evolution of the public transport funding policy in Madrid in recent years. We found that the increasing level of subsidy can hardly be explained on the basis of equity issues. Moreover, we claim that there is still room for a funding policy that makes the efficiency of the system compatible with its financial sustainability.  相似文献   
72.
73.
Abstract

Since 1990s the liner shipping industry has faced a period of restructuring and consolidation, and been confronted with a continuing increase in container vessel scale. The impact of these changes is noticeable in trade patterns, cargo handling methods and shipping routes, in short ‘operations’. After listing factors influencing size, growth in container ship size is explained by economies of scale in deploying larger vessels. In order to quantify economies of scale, this paper uses the liner service cash flow model. A novelty in the model is the inclusion of +6000-20-foot Equivalent Unit (TEU) vessels and the distinction in costs between single and twin propeller units on ships. The results illustrate that scale economies have been – and will continue to be – the driving force behind the deployment of larger container vessels. The paper then assesses the link between ship size and operations, given current discussions about the increase in container vessel scale. It is found that (a) ship size and operations are linked; (b) optimal ship size depends on transport segment (deep-sea vs. short-sea shipping, SSS), terminal type (transhipment terminals vs. other terminals), trade lane (East-West vs. North-South trades) and technology; and (c) a ship optimal for one trade can be suboptimal for another.  相似文献   
74.
The present paper presents the necessary crack growth statistics and suggests stochastic models for a reliability analysis of the fatigue fracture of welded steel plate joints. The reliability levels are derived from extensive testing with fillet-welded joints for which the entire crack growth history has been measured, not only the final fatigue life. The statistics for the time to reach given crack depths are determined. Fracture-mechanics-derived crack growth curves are fitted to the measured experimental curves and the best fit defines the growth parameters involved for each test specimen. The derived statistics and distribution function for these parameters are used as variables in a Monte Carlo simulation (MCS). In addition a Markov model is developed as an alternative stochastic model. It is a Markov chain for which the discrete damage states are related to chosen crack depths in the material. This model works directly with the experimental time statistics. It is a “stochastic bulk approach” not involving any random variables or fracture mechanics modeling. Both models are fitted to the data base and scaled to in-service conditions. Both methods are compared and discussed. The aim is to provide data for the variables used in a MCS and to develop a Markov chain for fast reliability calculation, especially when predicting the most likely influence of numerous future inspections.  相似文献   
75.
这是库布齐     
酊然  Tom 《汽车生活》2009,(6):66-75
Jeep Wrangler共3部,Sahara长短版本各一,主角是Rubicon,由它们去挑衅中国第7大沙漠:内蒙古库布齐——去征服和嬉戏。  相似文献   
76.
迷幻公园     
Sonnet  Tom 《汽车生活》2009,(10):20-27
看过Nick Hornby在2007年写的Slam(砰!),才刚16岁的玩板少年Sam,意外地使初恋女友怀孕,简直崩溃。单亲妈妈生下他时才17岁,十足少女母亲,现在这位老妈刚刚32岁,仍然美丽诱人。要是你的哥们儿叫你喝酒都顺便邀请你老妈,你说你会不会很窘?  相似文献   
77.
Port authorities generally focus on the development of the local port area and play a minor role in the development of port hinterlands, whereas shippers, forwarders, barge and rail operators have always been involved in the port-hinterland connection. The increasing importance of intermodal hinterland networks for the competitive position of ports has urged port authorities to become active in the hinterland. This new role has already been suggested by different academics. However, limited empirical evidence exists of port authorities taking stakes in inland terminals or developing transport services. Barcelona, as one of the leading port authorities in this respect, is used as a case study in this paper. The case study provides insight in the components and execution of the hinterland strategy of Barcelona. It shows that the strategy of the port authority of Barcelona and the consequent active involvement in the hinterland has had a significant impact on attracting container volumes from distant hinterlands and improving the accessibility of the port.  相似文献   
78.
参考CVT装在一辆奔驰A190车辆上,在3个测试循环及两种恒速状态下,通过认可的方法对油耗进行测量。表2所示的是采用绝对安全系数Sfabs=1.3的目前策略与新的控制策略之间的减少量。  相似文献   
79.
芝加哥已经同奥黑尔机场和中途机场开通了轨道交通线,目前正在筹划开通快速列车服务,以缩短运行时间,提高舒适性和可靠性。在建设过程中借鉴了世界其他机场快速线的成功经验,也遇到了很多的困难。  相似文献   
80.
This paper considers the market potential for battery electric and plug-in hybrid electric vehicles in Flanders, Belgium. Making use of a large-scale survey conducted in 2011 and applying a choice-based conjoint experiment, it is predicted that by 2020, battery electric vehicles could have a market share of about 5% of new vehicles, and plug-in hybrid electric vehicles could have a share of around 7%. By 2030, these figures could increase to 15% and 29%. The speed of up-take of electric vehicles, however, is sensitive to purchase costs.  相似文献   
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