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51.
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This paper concentrates on the determinants of investment and examines both theoretical and empirical work on the investment function. The major determinants are considered and a case study of the United Kingdom shipping industry in the period 1963-1987 is undertaken. The analysis is unable to find any real link between the value of the investment incentives packages available to the UK shipping industry and the size of the UK fleet during this period. The conclusion follows that while financial factors (e.g. favourable credit arrangements) or individual components (e.g. investment grants) of fiscal packages may influence the decision to invest, the total package has not affected the level of shipping investment in the manner expected.  相似文献   
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One of the great dilemmas facing major airports is the problem of capacity and seasonal surges of activity. This paper suggests a system of small, inexpensive Airport Terminal Modules, which together with a new type of Mobile Lounge, could make available a considerable degree of flexibility. The ATM's are designed to allow maximum variations of aircraft type and passenger load as well as high ground utilization. This concept would allow major airports to be extended with a minimum of inconvenience as demand becomes apparent, thereby allowing financial expenditure to be carefully controlled and more evenly spread.  相似文献   
55.

This paper reviews the provision of public transport in the Cape Town Metropolitan Area and the proposals for its future development. A vitally distinguishing characteristic of public transport in Cape Town and other South African cities is the fractured market with great discrepancies between different segments. These range from those with high incomes and preferences similar to those found in typically First World countries to a great majority living at or below minimum poverty levels with virtually no choices and a very different set of needs and preferences. Although scope for improving service levels and satisfying user needs is unlimited, in South Africa resources for transport are facing severe competition from other macrolevel social and economic imperatives, such as combating crime and addressing discrepancies in health and education needs. This situation represents a huge challenge to those responsible for planning and developing public transport strategies. Evidence is presented that current public transport services are unsustainable in terms of increasing subsidy requirements while also not effectively meeting user needs. Proposals to restructure the public transport system and to use Stated Preference techniques to identify user needs are put forward. Given the fractured market for public transport in metropolitan Cape Town, Stated Preference techniques will require innovative adaptations and different approaches to those most commonly applied elsewhere in the world and this paper provides some broad guidelines.  相似文献   
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Many car-following models predict a stable car-following behavior with a very small fluctuation around an equilibrium value g1 of the net headway g with zero speed-difference Δv between the following and the lead vehicle. However, it is well-known and additionally demonstrated by data in this paper, that the fluctuations are much larger than these models predict. Typically, the fluctuation in speed difference is around ±2 m/s, while the fluctuation in the net time headway T = g/v can be as big as one or even two seconds, which is as large as the mean time headway itself. By analyzing data from loop detectors as well as data from vehicle trajectories, evidence is provided that this randomness is not due to driver heterogeneity, but can be attributed to an internal stochasticity of the driver itself. A final model-based analysis supports the hypothesis, that the preferred headway of the driver is the parameter that is not kept constant but fluctuates strongly, thus causing the even macroscopically observable randomness in traffic flow.  相似文献   
58.
Peter 《世界汽车》2007,(1):68-69
外观最大的改变.来自于车头造型。乍看之下.或许会觉得似曾相识.没错.因为在Ford强调承袭家族风格的手法下.08款的Escape在车头的设计元素.更为接近Explorer与Expedition两位老大哥.而主导计划的首席设计师DoyleLetson也表示让Escape比以往更加强悍。  相似文献   
59.
Induced traffic and economic appraisal   总被引:1,自引:0,他引:1  
Economic appraisal of major roads in the UK is based on a set of standard procedures and conventions. A central assumption has been that the volume and pattern of traffic in any given year is independent of the quality of service offered by the network — the fixed trip matrix assumption. Failing to consider induced traffic can have serious consequences for the accuracy and robustness of the measured traffic benefits from road improvements. Assessment of the wider economic benefits of roads, which is an important political imperative for road investment, is also made more difficult. Two conclusions are reached. Variable trip matrix methods need to be introduced for the appraisal of major road schemes, and scheme appraisal needs to be complemented by a more strategic area-wide approach to evaluation. In responding to its advisory committee (SACTRA), the UK Department of Transport has accepted the first of these conclusions and is cautiously favourable to the second.  相似文献   
60.
Peter 《世界汽车》2007,(1):66-67
在大众旗下拥有最顶尖动力地位的“R”系列,继推出震惊全球”钢炮界”的GolfR32后.更于11月17日发表第二款R字头性能劲驹——PassatR361而PassatR36推出后.不仅荣登Passat车系的最快宝座.更一举拿下大众有史以来最劲猛的旅行轿车名号。  相似文献   
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