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11.
Freight transport demand is a demand derived from all the activities needed to move goods between locations of production to locations of consumption, including trade, logistics and transportation. A good representation of logistics in freight transport demand models allows us to predict the effects of changes in logistics systems on future transport flows. As such it provides better estimations of the costs of interaction and allows to predict changes in spatial patterns of freight transport flows more accurately. In recent years, the attention for freight modelling has been growing and new research work has appeared aimed at incorporating logistics in freight models. In this paper we review the state of the art in the representation of logistics considerations in freight transport demand models. Our focus is on the service and cost drivers of changes in logistics networks and how these affect freight transport. Our review proceeds along a conceptual framework for modelling that goes beyond the conventional 4-step modelling approach. We identify promising areas for freight modelling that have an integrative function within this framework, such as spatial computable general equilibrium models, supply chain choice models and hypernetwork models. 相似文献
12.
Igor Chorvath Michael A.DiPino 《汽车工艺与材料》2006,(10):18-19
燃料价格在短期内的上涨和全球有限的石油供应造成的长期威胁正在影响着汽车行业的发展趋势,因此急需寻找能够进一步提高燃油效率、降低废气排放的技术。消费者对汽油价格的担忧以及对于汽车尾气对环境影响的日益关注,推动着世界各地的汽车研究人员不断研发矿物燃料的替代品,如 相似文献