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991.
Congestion pricing schemes have been traditionally derived based on analytical representations of travel demand and traffic flows, such as in bottleneck models. A major limitation of these models, especially when applied to urban networks, is the inconsistency with traffic dynamics and related phenomena such as hysteresis and the capacity drop. In this study we propose a new method to derive time-varying tolling schemes using the concept of the Network Fundamental Diagram (NFD). The adopted method is based on marginal cost pricing, while it also enables to account realistically for the dynamics of large and heterogeneous traffic networks. We derive two alternative cordon tolls using network-aggregated traffic flow conditions: a step toll that neglects the spatial distribution of traffic by simply associating the marginal costs of any decrease in production within the NFD to the surplus of traffic; and a step toll that explicitly accounts for how network performance is also influenced by the spatial variance in a 3D-NFD. This pricing framework is implemented in the agent-based simulation model MATSim and applied to a case study of the city of Zurich. The tolling schemes are compared with a uniform toll, and they highlight how the inhomogeneous distribution of traffic may compromise the effectiveness of cordon tolls.  相似文献   
992.
Retail traffic is one of the main drivers for the growth of intermodal transport services in the UK. This paper examines the key factors underpinning this modal shift in order to learn lessons for other market and geographical contexts. Since successful retail intermodal logistics involves many actors, this paper is based on semi-structured interviews with major UK retailers, third-party logistics providers (3PLs) and rail operators, supplemented by document analysis. The qualitative data are analysed via a conceptual framework derived from the literature. Despite past successes and the presence of drivers for future growth, the paper identifies many operational issues without current solutions and the presence of ongoing public subsidy. The major conclusion is that the importance of 3PLs, aggregation and multi-user platforms must be recognised by transport planners in supporting the use of intermodal transport by retailers and other large shippers.  相似文献   
993.
通过文献调研,采用纵向比较的方法,文章分析了我国与美国、欧盟、日本等发达国家及地区公路运输场站绿色低碳的发展政策和技术应用现状,并针对我国公路运输场站发展实际,提出了今后公路运输场站绿色低碳发展的几点建议。  相似文献   
994.
This research provides new evidence about the relationship between travel behavior, workplace diversification, and environmental impact in the United Kingdom using data from the National Travel Survey for the period between 2002 and 2017. The path analysis approach based on SEM handles both direct and indirect effects and allows for a comprehensive study of travel behavior, trade-off effects, and work and non-work trips. The results suggest that workplace diversification is often reflected by longer average distances for work trips, which are often associated with more remote residential locations. Findings also show that for some categories, such as teleworkers and home-based workers, trade-off effects are observed between work and non-work trips, which increase CO2 emission levels.  相似文献   
995.
客车与火车和飞机的成渝城际客运之争   总被引:1,自引:0,他引:1  
从技术、经济与社会角度分析城际高速客运的市场经济特征,并根据市场变化趋势对客车技术和管理体制进行论述。  相似文献   
996.
This paper reports the insights into environmental impacts of the ongoing transformative land use and transport developments in Greater Beijing, from a new suite of dynamic land use, spatial equilibrium and strategic transport models that is calibrated for medium to long term land use and transport predictions. The model tests are focused on urban passenger travel demand and associated emissions within the municipality of Beijing, accounting for Beijing’s land use and transport interactions with Tianjin, Hebei and beyond. The findings suggests that background trends of urbanization, economic growth and income rises will continue to be very powerful drivers for urban passenger travel demand across all main modes of transport beyond 2030. In order to achieve the dual policy aims for a moderately affluent and equitable nation and reducing the absolute levels of urban transport emissions by 2030, road charging and careful micro-level coordination between land use, built form and public transport provision may need to be considered together for policy implementation in the near future.  相似文献   
997.
Charging infrastructure requirements are being largely debated in the context of urban energy planning for transport electrification. As electric vehicles are gaining momentum, the issue of locating and securing the availability, efficiency and effectiveness of charging infrastructure becomes a complex question that needs to be addressed. This paper presents the structure and application of a model developed for optimizing the distribution of charging infrastructure for electric buses in the urban context, and tests the model for the bus network of Stockholm. The major public bus transport hubs connecting to the train and subway system show the highest concentration of locations chosen by the model for charging station installation. The costs estimated are within an expected range when comparing to the annual bus public transport costs in Stockholm. The model could be adapted for various urban contexts to promptly assist in the transition to fossil-free bus transport. The total costs for the operation of a partially electrified bus system in both optimization cases considered (cost and energy) differ only marginally from the costs for a 100% biodiesel system. This indicates that lower fuel costs for electric buses can balance the high investment costs incurred in building charging infrastructure, while achieving a reduction of up to 51% in emissions and up to 34% in energy use in the bus fleet.  相似文献   
998.
999.
Previous research has shown integrated planning to be important for achieving aims concerning more environmentally friendly transport operations, but less good at explaining prerequisites of implementation. This paper analyses how management and working practises in local authorities, here understood as steering cultures, affect implementation of integrated land-use and public transport planning approaches. The analysis builds on case studies of planning in two Swedish municipalities. These have developed two antithetical steering cultures, namely one that can be described as deliberative and one that can be described as sectorised. The paper describes the advantages and disadvantages of these steering cultures. The findings show the deliberative model to facilitate integration through advanced mechanisms of consensus and co-ordination between policy-makers and officials. The sectorised model has no such mechanisms, but this need not result in poor prospects of integrated planning. It is important for integrated planning approaches, whatever the steering culture, to be in line with the institutionalised norms and objectives by which planning practices are governed. Integration therefore needs a normative component, so as to ensure implementation. The important normative component in this context can be construed as discourses and rationales concerning transport and the urban development of which public transport forms part.  相似文献   
1000.
There are recent evidence that air transport demand may not have a perfectly reversible relationship with income and jet fuel prices, as is assumed in most demand models. However, it is not known if the imperfectly reversible effects of jet fuel price are a result of asymmetries in the supply side, i.e., asymmetries in cost pass through from fuel prices to air fare, or of demand side behavioral asymmetries whereby people value gains and losses differently. This paper uses US time series data and decomposes air fare and fuel price into three component series to develop an econometric model of air transport demand that is capable of capturing the potential imperfectly reversible relationships and test for the presence or absence of reversibility. We find that air transport demand shows asymmetry with respect to air fare, indicating potential imperfect reversibility in consumer behavior. We also find evidence of asymmetry and hysteresis in cost pass-through from jet fuel prices to air fare, showing rapid increases in airfare when fuel prices increases but a slower response in the opposite direction.  相似文献   
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