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41.
黄炜炳 《汽车杂志》2010,(1):270-270
前段时间和国内几家权威IT媒体主编交流,他们无一例外地抱怨现在导航厂商都不投放广告,令网站的内容更新与生存倍感压力。  相似文献   
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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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This paper presents a case study which tackles a general problem for railway management, namely the formulation of a strategy to improve business financial performance. This is prefaced, in Section 2, by discussion of general principles - concerning the type of information system required, investigations to be conducted and associated measurement needs. The case study, of Section 3, concerns our investigations of VicRail's total business and its constituents. The task of financial improvement is revealed from an assessment of sectors' current cost-recovery positions and the identification of system joint costs. For freight sectors, future traffic prospects, pricing possibilities and the scope for more efficient operations are then considered, and the implications traced for overall deficit reduction and the development of business strategy. The concluding section draws some general lessons for railway managements.A fuller discussion by the authors of the theoretical framework employed, and particularly of the case study application, is contained in a complimentary publication: Improving Railway Financial Performance, published by Gower in January 1985.Transmark is a subsidiary of the British Railways Board, acting as its international consultancy. The authors, who were respectively study director and manager, wish to thank Bernard Warner (an independent consultant), Richard Eccles (of Transmark) and Adrian Balkyn-Rackowe (of British Rail) for their valuable contributions. The study report, titled Rail Cost — Pricing Options, was released by the Minister in April 1981.  相似文献   
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Using current meters and systematically repeated vessel mounted ADCP data legs, we describe the role of the semidiurnal and diurnal constituents in the tidal currents and investigate the mesoscale variability of the M2 tidal currents field along three cross-shelf legs over the Galician shelf. We found that the estimated values of the semi-major axes of the main semidiurnal tidal constituents are closely related to those obtained in previous research and that the tidal currents are predominantly semidiurnal. Amplitudes of the M2 and S2 semi-major axes constituents are comparable, and important fortnightly variability should thus be expected in the amplitude of the semidiurnal tidal currents. Vertical profiles of the semi-major axes of the main tidal constituents reveal that, in the absence of stratification, and far from the bottom frictional effects, the tidal currents are mostly barotropic. Over the slope, the tidal ellipses tilt from a north–south orientation toward the northeast–southwest direction and, as we go further into the shelf, their amplitude is increased, a feature that is reasonably explained by the transition from the dynamics of a Poincaré wave offshore to the dynamics of a northward alongshore propagating Kelvin wave over the shelf. The Ría de Vigo exerts a notable influence over the tidal currents, acting as an extension of the shelf and introducing a meridional variation in the orientation of the ellipses from the alongshore direction in the southern straight coast toward the northeast–southwest direction at the latitude of the Rías. Finally, the spatial fitting methods we tried have proved to be successful in VMADCP data detiding in this region.  相似文献   
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According to the mid-term review of the EU White Paper on Transport, Short Sea Shipping (SSS) is expected to grow at a rate of 59% (metric tonnes) between 2000 and 2020. If we consider that the overall expected increase in both freight exchanges and volume is 50%, sea transport is one of the most feasible alternatives to reduce traffic congestion on European roads. Maritime transportation may compete with road transport as far as certain traffics are concerned, but only when assuming external costs. This paper analyzes several intermodal transport chains involving a sea leg by comparing the effect of pollutant emissions from different ship types and road transport in terms of potential external cost savings. The translation of these emissions into environmental costs shows, for certain conditions, savings in the case of sea transport that would justify the use of an environmental bonus to promote the sea option.  相似文献   
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2008年导航市场将进入洗牌阶段。随着许多国际大品牌GARMIN、TOMTOM等都纷纷进入中国市场瓜分导航市场的这块蛋糕,中国的中、小品牌生存空间将受到挤压,甚至,许多小品牌在今年或明年将有可能会消失。那么,怎么才能继续生存并有比较好的前景呢?  相似文献   
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严峻问题     
今年关于太平洋航线有两个不确定因素,即美国进口量增长将会大大放缓,同时美国出口量会继续增加.因此,几乎所有其他的问题都是不确定的:进口量是否会增长还是会减少?  相似文献   
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