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41.
42.
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   
43.
Travel time reliability is considered to be one of the key indicators for the performance of transport systems and is measured in various ways. This paper synthesizes both reliability concepts: traffic breakdown, the indicator of the instability of travel times, is treated as the risk, whereas travel time variability, the indicator of the uncertainty of travel times, is considered as the consequence of this risk. An analytical formula, using risk assessment technique, explicitly expresses the cost of travel time unreliability as the sum of the products of the consequences (i.e. variability) and the corresponding probabilities of breakdown. It provides a novel measure of travel time reliability and is applicable in network performance evaluations. An empirical example based on a large dataset of freeway traffic flow data from loop detectors shows that the developed travel time reliability measure is both intuitively logical and consistent.  相似文献   
44.
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   
45.
Continuously updated knowledge of the friction potential and the friction demand can help to improve manoeuvrability and thereby safety of vehicles under slippery road conditions. An on line friction estimation method is presented using a simple brush type tyre model. First the method is verified by outdoor experiments using a tyre test trailer. Then the setup of a low-cost measurement system in a vehicle is discussed and results from both simulations and outdoor experiments are presented. Neural networks have been used both for modelling and identification of friction potential and friction demand.  相似文献   
46.
This paper analyses foreign direct investments (FDI) in Asia by the Norwegian maritime industry. It focuses on three topics: (1) Why do Norwegian maritime companies invest abroad? (2) What are the effects of maritime foreign direct investments on the Norwegian maritime milieu? (3) What are the effects of these investments on the host country? By analysing specific Norwegian maritime companies, it was found that the FDIs have partly been induced by the instability of the Norwegian policy towards this sector. Several firms also point at the importance of being closer to the Asian market as a significant reason for FDI, and the Norwegian ship equipment industry tends to 'follow' the shipping companies abroad. The domestic effects of FDI are uncertain, and are likely to depend on the motivation behind the investments. Finally, using Singapore as an example, it is argued that the host country effects of FDI tend to be positive.  相似文献   
47.
An approximate method is presented which produces a handling diagram useful for the study of steady-state turning behaviour at different values of steer angle, path radius and speed In three successive parts the steady state response of simple and more elaborate vehicle models and the stability of the resulting motion are discussed.  相似文献   
48.
A dynamical model is presented to analyse the stability of motion of the two-wheeled 'Fokker F.28-like' landing gear including tyres. The model is equally applicable to similar landing gears. The influence of the introduction of a specially designed torsional damper on the dynamical behaviour of the landing gear-tyre combination is investigated. Results of the stability calculations are supported by test results.  相似文献   
49.
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   
50.
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   
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