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31.
Luo  Ding  Cats  Oded  van Lint  Hans 《Transportation》2020,47(6):2757-2776
Transportation - We present a pioneering investigation into the relation between passenger flow distribution and network properties in public transport systems. The methodology is designed in a...  相似文献   
32.
Abstract

Each year more than 1000 pedestrians are injured in accidents on pedestrian crossings in Switzerland. The accidents often occur in darkness, twilight or poor visibility during rain at locations without sufficient public street lighting because vehicle drivers notice the pedestrian crossing too late or overlook it altogether. Pedestrian crossings can be made significantly easier for vehicle drivers to recognize at night and in poor visibility by means of HMB reflectors. When crossing sites are made more conspicuous with high horizontal retro‐reflecting markers, the readiness to stop increases. The reflectors can thus contribute to improving road safety at pedestrian crossings. This new low‐cost measure has a wide range of applications. The new reflector system is currently gaining ground in Switzerland and several other European countries.  相似文献   
33.
The objective of this study is to examine the effect of road pricing on people’s tendency to adapt their current travel behavior. To this end, the relationship between changes in activity-travel behavior on the one hand and public acceptability and its most important determinants on the other are investigated by means of a stated adaptation experiment. Using a two-stage hierarchical model, it was found that behavioral changes themselves are not dependent on the perceived acceptability of road pricing itself, and that only a small amount of the variability in the behavioral changes were explained by socio-cognitive factors. The lesson for policy makers is that road pricing charges must surpass a minimum threshold in order to entice changes in activity-travel behavior and that the benefits of road pricing should be clearly communicated, taking into account the needs and abilities of different types of travelers. Secondly, earlier findings concerning the acceptability of push measures were validated, supporting transferability of results. In line with other studies, effectiveness, fairness and personal norm all had a significant direct impact on perceived acceptability. Finally, the relevance of using latent factors rather than aggregate indicators was underlined.  相似文献   
34.
ERTMS/ERTML是欧洲铁路运输系统管理层的缩写(European Rail Traffic Management Sys-tem/European Rail Traffic Management Layer).ERTML的目标是建立一个高层次的全欧洲铁路运输管理系统.到目前为止,影响其运作决策的主要因素是双边协议及合同.  相似文献   
35.
Using the SKAGEX dataset for evaluation of ocean model skills   总被引:1,自引:0,他引:1  
Numerical ocean models are now being applied in numerous oceanographic studies. However, the qualities of the model results are often uncertain and there is a great need for standards and procedures for evaluation of the skills of numerical general circulation models. In this paper measurements from repeated hydrographical sections across Skagerrak taken in 1990, the SKAGEX dataset, are used to evaluate the skills of two σ-coordinate ocean models and to study the sensitivity of these models to model parameters. A methodology for quantification of model skills based on observations from repeated hydrographical sections in general is suggested. Area averages of absolute differences are for Skagerrak completely dominated by the discrepancies in the upper few meters of the ocean and may not be used to assess models' abilities to reproduce the fields in the larger and deeper part of the ocean. Therefore, discrepancies between average values in time from the observed fields and time averaged values from model outputs are related to the natural variability of the fields. The numbers produced with the suggested measure are relative numbers that will be specific for each section and for each series of observation. Ideally we would therefore like to see the measures computed for a number of sections for various models and choices of model parameters in order to assess model skills. The value of the SKAGEX dataset as a tool for model improvements is demonstrated. Evidence to support the importance of applying non-oscillatory, gradient preserving advection schemes in areas with sharp density fronts is given. The method is used to identify that the forcing/initial values/boundary values for the temperature field are inferior to the corresponding values for the salinity field. With the present coarse resolution, 11 layers in the vertical, it is shown that it is far from obvious that the quality of the model results improve when replacing simple Richardson number formulations for vertical mixing processes with higher order turbulence closure in the Skagerrak area.  相似文献   
36.
Long-term changes of environmental conditions are fundamentally important for many sectors in the maritime industry. Observational evidence from which such long-term changes may be reliably derived is often limited. Here we briefly illustrate the present situation and present an approach on how quasirealistic environmental models can be used in combination with existing data to reconstruct recent long-term changes and to derive scenarios of future developments. We concentrate on variables of primary importance for the maritime industry, namely wind-storms, wind-waves and storm surges. Examples are provided for the North Sea area.  相似文献   
37.
This article is based on 183 819 port state control inspections from various port state control regimes for the time frame 1999 to 2004. Using binary logistic regression, we establish the differences of port state control inspections across several regimes, even though theory predicts there should be no significant differences in treatments of vessels. The results indicate that the differences towards the probability of detention are merely reflected by the differences in port states and the treatment of deficiencies and not necessarily by age, size, flag, class or owner as perceived by the industry and regulators. The analysis further shows that some differences can be found across ship types and regimes and that there appears to be room for further harmonization in the area of port state control.  相似文献   
38.
39.
In transport literature there is an ongoing discussion on the potential of light rail in mitigating congestion and supporting mobility around urban centres. Throughout Europe and the United States, many policy makers see light rail as an interesting option to improve the accessibility of urban centres. The Dutch national government wanted to support swift light rail realization in a number of promising situations.Several projects gained support from the national government for implementation. However, the decision-making on a local level was not nearly as swift as expected and not in line with the promise. This paper presents an analysis of that perceived slowdown and shows that the approach of the national government with a strict focus on light rail and a detachment from the local processes has played an important role in the slowdown. It shows that light rail can very well be a solid option. However, its successful implementation is not solely dependent on light rail suitability for the mobility patterns in the region, but very much on the approach of the implementation of those supporting the option.  相似文献   
40.
During the Soviet era most of the Union's international non-oil trade was transported over water. Following the former Soviet Union's break-up, the share of water transport in accomodating Russia's trade has become modest, as the railways carry most goods that are traded domestically or with the new republics of the Commonwealth of Independence States, which are now treated as foreign countries. Adjusting the Russian Federation's water transport industry and related infrastructure to the changed geo-political and regional economic conditions proves difficult. While the country inherited a fair share of the former Soviet merchant fleet, it is deprived of port assets which were originally built to serve all-Union trades but are now located in other republics of the Commonwealth of Independent States. Major reforms are required to streamline the provision of port services and the ports' commercial performance. The Russian Government took several steps in 1992 which effectively put the national water transport carriers on a commercial footing. The effect has been that many carriers chose to leave the national transport scence and engage in trades which do not include Russia. The Government is now confronted with the need to reduce dependence on foreign-owned vessels and to modernize the national merchant fleet. Difficult policy decisions have to reverse these trends so that national maritime industry asstes become more available to meet the country's needs.  相似文献   
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