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11.
Transportation - Electronic Toll Collection (ETC) systems are based on tags, on-board units associated to personal bank accounts, used for paying tolls electronically. Despite the benefits...  相似文献   
12.
The US Highway Capacity Manual (HCM) methodology is used in Spain to evaluate traffic operation and quality of service. The effect of passing manoeuvre on two‐lane highway operational performance is considered through adjustment factors to average travel speeds and percent time spent following. The procedure is largely based on simulations in TWOPAS and passing behaviours observed during US calibrations in the 1970s. It is not clear whether US driving behaviour and vehicles' performance are comparable with Spanish conditions. The objective of this research is to adapt the HCM 2010 methodology to Spanish driver behaviour, for base conditions (i.e. no passing restrictions). To do so, TWOPAS was calibrated and validated based on current Spanish passing field data. The calibration used a genetic algorithm. The case study included an ideal two‐lane highway with varying directional traffic flow rate, directional split and percentage of trucks. The updated methodology for base conditions is simpler than the current HCM 2010 and does not rely on interpolation from tables. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
13.
Establishing a European wide high-quality shipping links and integrating them with the trans-European Transport networks has been the vision of the European Commission (EC) to reduce land transport congestion under the Motorways of the Sea (MoS) concept. However, in spite of strong political backing and favourable policy initiatives, MoS projects have met with limited success. Establishing MoS is complex because of its international scope and involvement of a number of public and private stakeholders with conflicting objectives and goals. The paper attempts to identify critical factors for establishing viable MoS projects. The paper reviews the development of the MoS concept to understand the expectations of the EC and the concerns of the important stakeholders. The present status of these policy actions is reviewed and their possible effect on the performance of MoS projects is estimated. Case studies of short sea shipping initiatives in different parts of Europe and the world are reviewed to learn from their successes and failures. This knowledge is applied to find critical factors for the success of MoS projects in the European context.  相似文献   
14.
This study investigates travel behavior determinants based on a multiday travel survey conducted in the region of Ghent, Belgium. Due to the limited data reliability of the data sample and the influence of outliers exerted on classical principal component analysis, robust principal component analysis (ROBPCA) is employed in order to reveal the explanatory variables responsible for most of the variability. Interpretation of the results is eased by utilizing ROSPCA. The application of ROSPCA reveals six distinct principal components where each is determined by a few variables. Among others, our results suggest a key role of variable categories such as journey purpose-related impedance and journey inherent constraints. Surprisingly, the variables associated with journey timing turn out to be less important. Finally, our findings reveal the critical role of outliers in travel behavior analysis. This suggests that a systematic understanding of how outliers contribute to observed mobility behavior patterns, as derived from travel surveys, is needed. In this regard, the proposed methods serve for processing raw data typically used in activity-based modelling.  相似文献   
15.
IntroductiollAnyelectricalconductorplacedinatime-varyingmagneticfieldistheseatofeddycurrentsthatdissipatepowerthroughJouleeffect.ThispowerisconcentratedinthesurfaceofthecomPonent,inaverysmallthicknesswhichdependsontheelectricalconductivityandmagneticpermeabilityofthematerial,butalsoonthefrequencyofthecurrents.Inductionhardeningprocessestakeadvantageofthiseffectbecauseitthereforepossibletocontrolthethicknessofthetreatedlayer.InductionhardeningofsteelcomPonentsisrealisedintwosteps.First,anindu…  相似文献   
16.
在线弹性假设基础上, 根据有限元理论和桥梁随机车辆( 行人) 荷载的特点, 讨论并提出了一种通过监测部分位移, 计算桥梁其余位移和桥面荷载的简化分析方法, 解决了桥梁在随机车辆( 行人) 荷载作用下的荷载确定问题, 建立了动位移和等效节点荷载的有限元列式. 该方法为桥梁结构的在线监测和实时分析提供了理论基础, 适用于连续梁桥、拱桥、斜拉桥和悬索桥等桥梁结构形式, 具有实际应用价值  相似文献   
17.
Abstract

A model is proposed to calculate the overall operating and delay times spent at bus stops due to passenger boarding and alighting and the time lost to queuing caused by bus stop saturation. A formula for line demand at each stop and the interaction between the buses themselves is proposed and applied to different bus stops depending on the number of available berths. The application of this model has quantified significant operational delays suffered by users and operator due to consecutive bus arrival at stops, even with flows below bus stop capacity.  相似文献   
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19.
We have formalized and parameterized a model for the production of six transport fuels and six fuels blends from six feedstocks through 13 different production chains, and their adoption of by 11 distinct subpopulations of motorists. The motorists are represented by agents that use heuristics to choose a fuel on the basis of three attributes and a social feedback loop. Adoption of specific fuels is mostly driven by price differences, but other factors play a role if prices are similar. The results are not always intuitive and do not always show up immediately. We find that sustained combinations of interventions are required to bring about a transition away from petrol or diesel. Adoption of alternative fuels was most often confined to niche markets with a share of 5% or lower. Only in a single case was a complete fuel transition observed.  相似文献   
20.
Cantos  Pedro  Pastor  José M.  Serrano  Lorenzo 《Transportation》1999,26(4):337-357
The purpose of this paper is to analyse the evolution of productivity in the European railways in the period 1970–95. We use a non-parametric approach that enables changes in productivity to be broken down into variations in efficiency and technical change. The results indicate that the productivity growth is concentrated in the last period (1985–95), when the majority of the companies undertook processes of reforms. This increase in productivity is mainly due to technical progress. We also analyse the determinants of efficiency and, unlike other papers, the technical change, finding that the greater the degree of autonomy and financial independence, the higher the efficiency levels and technical change. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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