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41.
Jonn Axsen Kenneth S. Kurani 《Transportation Research Part D: Transport and Environment》2010,15(4):212-219
Plug-in hybrid electric vehicles (PHEVs) can be powered by gasoline, grid electricity, or both. To explore potential PHEV energy impacts, a three-part survey instrument collected data from new vehicle buyers in California. We combine the available information to estimate the electricity and gasoline use under three recharging scenarios. Results suggest that the use of PHEV vehicles could halve gasoline use relative to conventional vehicles. Using three scenarios to represent plausible conditions on PHEV drivers’ recharge patterns (immediate and unconstrained, universal workplace access, and off-peak only), tradeoffs are described between the magnitude and timing of PHEV electricity use. PHEV electricity use could be increased through policies supporting non-home recharge opportunities, but this increase occurs during daytime hours and could contribute to peak electricity demand. Deferring all recharging to off-peak hours could eliminate all additions to daytime electricity demand from PHEVs, although less electricity is used and less gasoline displaced. 相似文献
42.
The World Bank urban transport strategy review, “Cities on the Move” analyzed urban transport problems in developing and transitional economies and articulated a proposed strategy framework for national and city governments. This paper describes how the urban transport problems of the developing world have changed in the last decade and assesses the extent to which the strategies recommended in 2002 have been successfully implemented. It shows that progress has been widespread in some areas – particularly in mass transit analysis and investment and some environmental policies – and that there have developed some good planning and public transport practices in a smaller number of model cities. But more strategic institutional and policy issues, including the mobilization and regulation of private sector initiative in meeting infrastructure and public transport supply deficiencies, have tended to be poorly developed. Above all, the growth of medium sized cities with weak institutions and finance highlights the need for the international development institutions to put greater emphasis on helping those cities by dissemination of best practice in strategic transport planning and traffic management. 相似文献
43.
Kenneth Rose 《Transportation》1975,4(1):55-66
Utilizing data collected for urban transportation studies in Ontario, regression analysis has been used to establish relationships between the daily number of person trips in an urban area and the area population. In particular the number of trips by auto drivers, auto passengers and mass transit riders have been investigated. Further, auto driver trips have been stratified into the following destination trip purposes: return home, work and related business, shopping, social-recreational and miscellaneous. The results of this analysis have been used to prepare a set of design charts. These charts are presented graphically and in the form of a nomogram. The accuracy of these charts has been investigated and found satisfactory for most planning purposes. 相似文献
44.
Coleen L. Moloney Michael A. St John Kenneth L. Denman David M. Karl Friedrich W. Köster Svein Sundby Rory P. Wilson 《Journal of Marine Systems》2011,84(3-4):106-116
Marine food web dynamics are determined by interactions within and between species and between species and their environment. Global change directly affects abiotic conditions and living organisms, impinging on all trophic levels in food webs. Different groups of marine researchers traditionally study different aspects of these changes. However, over medium to long time scales perturbations affecting food webs need to be considered across the full range from nutrients to top predators. Studies of end-to-end marine food webs not only span organism sizes and trophic levels, but should also help align multidisciplinary research to common goals and perspectives. Topics are described that bridge disciplinary gaps and are needed to develop new understanding of the reciprocal impacts of global change on marine food webs and ocean biogeochemistry. These include (1) the effects of nutrients on biomass and production, (2) the effects of varying element ratios on food web structure and food quality, (3) bulk flows of energy and material in food webs and their efficiencies of transfer, (4) the ecological effects of species richness and the roles of microbial organisms, (5) the role of feeding behaviour in food web dynamics and trophic controls, (6) the spatial dynamics of communities and links between different food webs, (7) the combined effects of body size and behaviour in determining dynamics of food webs, and (8) the extent to which the ability of marine organisms (and communities) to adapt will influence food web dynamics. An overriding issue that influences all topics concerns the time and space scales of ecosystem variability. Threads link different nodes of information among various topics, emphasizing the importance of tackling food web studies with a variety of modelling approaches and through a combination of field and experimental studies with a strong comparative approach. 相似文献
45.
Kenneth Button 《运输评论》2013,33(3):189-215
After forty years of economic regulation, the U.S. interstate aviation industry was ‘deregulated’ in 1978. This paper offers an assessment of the reasons for this radical change in official federal policy and an evaluation of the longer term impact of the reforms. Further, it provides a number of observations regarding the universality of the experiences of the U.S.A. in the context of the gradual liberalization of aviation regulation in general and the ‘deregulation’ of European aviation in particular. 相似文献
46.
Elizabeth McLeod Alison Green Edward Game Kenneth Anthony Joshua Cinner Scott F. Heron 《Coastal management》2013,41(6):651-672
Tropical coastal and marine ecosystems are particularly vulnerable to ocean warming, ocean acidification, and sea-level rise. Yet these projected climate and ocean change impacts are rarely considered in conservation planning due to the lack of guidance on how existing climate and ocean change models, tools, and data can be applied. Here, we address this gap by describing how conservation planning can use available tools and data for assessing the vulnerability of tropical marine ecosystems to key climate threats. Additionally, we identify limitations of existing tools and provide recommendations for future research to improve integration of climate and ocean change information and conservation planning. Such information is critical for developing a conservation response that adequately protects these ecosystems and dependent coastal communities in the face of climate and ocean change. 相似文献
47.
In this paper we present a route-level patronage model that incorporates transit demand, supply and inter-route effects in a simultaneous system. The model is estimated at the route-segment level by time of day and direction. The results show strong simultaneity among transit demand, supply and competing routes. Transit ridership is affected by the level of service, which in turn is determined by current demand and ridership in the previous year. The model demonstrates that a service improvement has a twofold impact on ridership; it increases ridership on the route with service changes, but it also reduces the ridership on competing routes so that the net ridership change is small. The model is thus useful for both system-level analysis and route-level service planning. 相似文献
48.
Kenneth F.D. Hughey Geoffrey N. Kerr Ross Cullen 《Transportation Research Part D: Transport and Environment》2011,16(8):575-578
Based on a public survey of registered voters, we explore four options for internalising the social and environmental costs of road transport. The options were presented together with generalised factual information about their benefits and costs. Respondents are highly supportive of fuel use efficiency standards and exhaust gas quality standards, with lesser support for proposed initiatives of road user charges and speed reduction. Demographic analysis of responses enables identification of those who might favour or oppose particular options. In this case women are identified as being strongly supportive of the speed reduction option. 相似文献
49.
<正>本书收录的12篇论文,系20世纪80年代初由东南亚英国学院资助召开的两次学术研讨会的研究成果,令人耳目一新。这些文章对东南亚部分重要地区从古代至19世纪末的贸易与政体之间的相互关系进行了选择性的探讨。不过,书中绝大部分的论文讨论的是1400年之后的情况,当时,贸易的迅速增长限制了该地区传统权力的变动。书中仅有一篇有关阿瑜陀耶(Ayutthaya)的文章考察了东南亚大陆的非马来地区。 相似文献
50.
Transport demand in western Europe has risen steadily in recent years and the forecasts are that the unrestrained demand will continue to rise in the foreseeable future. This growth has put considerable pressure on the resources available to finance infrastructure investments and to fund what are seen as socially important social services. The recent developments in eastern Europe and the anticipated growth of the post-Communist states will put further strains on the fiscal ability of authorities in these countries to fund transport investments and operations. The outcome has been revisions in the way transport projects are funded. This paper, taking a very broad view of what constitutes a transport project, examines the specific nature of urban transport financing in Europe. 相似文献