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131.
马德里已经成为城市地下公路与铁路基础设施安全高效发展的一个全球典范.作为改善城市交通系统与公共运输网络的有效投资典范,文章详细介绍了过去12年中地铁网络的发展以及目前M-30环线改建项目情况,分析总结了马德里获得成功的关键因素.  相似文献   
132.
Appropriate port regulation and competitive forces tend to be related to higher levels of operational and economic performance of ports. From a policy-making perspective, pursuing efficiency and securing competition in ports to reach a level playing field is a two-step process requiring (1) ex-ante regulations to set the rules that maximize the competition for the market, especially when the policy objective is to attract private operations to ports on competitive concession processes and (2) ex-post competition policy to monitor and preserve competition in the market. This paper studies port regulation in Latin America and the Caribbean (LAC) from a competition perspective, analyzing both ex-ante and ex-post policies implemented in the region. The analysis reveals that the competitive environment in LAC is low, giving room for possible anticompetitive practices in the LAC port sector. Since the end of the 1990s, approximately 80% of container terminals in the region were granted to only five companies. Chile and Mexico have been found to be the best practices in the region, with better conditions assuring robust competition in the market. The main policy implication from this analysis is the need for a stronger involvement of antitrust agencies throughout the port concession processes.  相似文献   
133.
Literature has focused on studying port choice independently or as an element of a supply chain without considering the joint selection with the country of origin/destination of the imports/exports. However, the characteristics and location of a port may make it more attractive to mobilise more freight from/to some particular countries rather than others, making the port choice decision dependent on the country of origin/destination of the cargo. This article proposes advanced econometric models to evaluate simultaneously port choice and the country of origin/destination choice for Colombian imports and exports. Findings suggest that for imports and exports domestic freight rate is the most important variable for the joint choice process. Also, for exports, maritime transit time is more relevant than for imports, while for the frequency of shipping lines the opposite is true. The existence of a trade agreement and the gross domestic product per capita also have a significant influence on the election of a country for exports/imports.  相似文献   
134.
Traffic volume data are key inputs to many applications in highway design and planning. But these data are collected in only a limited number of road locations due to the cost involved. This paper presents an approach for estimating daily and hourly traffic volumes on intercity road locations combining clustering and regression modelling techniques. With the aim of applying the procedure to any road location, it proposes the use of roadway attributes and socioeconomic characteristics of nearby cities as explanatory variables, together with a set of previously discovered patterns with the hourly traffic percent distribution. Test results show that the proposed approach significantly produces accurate estimates of daily volumes for most locations. The accuracy at hourly level is a bit more reduced but, for periods when traffic is significant, more than half of the estimates are within 20% of absolute percentage error. Moreover, the main peak period is approximately identified for most cases. These findings together with its great applicability make this approach attractive for planners when no traffic data are available and an estimate is helpful.  相似文献   
135.
The State-owned Spanish Port System (SPS) includes 46 ports for general use that are managed by the 28 port authorities distributed along the 8000 km of Spanish coast. SPS has not grown at a rate comparable to that of international maritime transportation. In our paper, we start from the hypothesis of a port system that appears to be oversized, subsidized, with regard to container traffic. Quantifying the maximum operational capacity of the different container terminals along the Spanish coast and their mooring capacities will provide the available dimensions for this type of traffic. In a second step, we will analyse whether SPS are sufficient (according to the perspective of international standards) to meet Spain’s needs, which is related to Spain’s strategic geographic location and its need to move containerized cargo for the domestic market. The paper concludes SPS has an oversized that limits competitiveness, which is indicated by the average transshipment ratio of approximately 50% and an average unweighted idle ratio of port facilities designed for container traffic of over 60% in the eight main ports.  相似文献   
136.
This paper describes a real-time vision-based blind spot warning system that has been specially designed for motorcycles detection in both daytime and nighttime conditions. Motorcycles are fast moving and small vehicles that frequently remain unseen to other drivers, mainly in the blind-spot area. In fact, although in recent years the number of fatal accidents has decreased overall, motorcycle accidents have increased by 20%. The risks are primarily linked to the inner characteristics of this mode of travel: motorcycles are fast moving vehicles, light, unstable and fragile. These features make the motorcycle detection problem a difficult but challenging task to be solved from the computer vision point of view. In this paper we present a daytime and nighttime vision-based motorcycle and car detection system in the blind spot area using a single camera installed on the side mirror. On the one hand, daytime vehicle detection is carried out using optical flow features and Support Vector Machine-based (SVM) classification. On the other hand, nighttime vehicle detection is based on head lights detection. The proposed system warns the driver about the presence of vehicles in the blind area, including information about the position and the type of vehicle. Extensive experiments have been carried out in 172 minutes of sequences recorded in real traffic scenarios in both daytime and nighttime conditions, in the context of the Valencia MotoGP Grand Prix 2009.  相似文献   
137.
The Panama Canal is currently in the process of a major expansion effort. After the new set of locks is opened in 2016, significantly larger ships can traverse the Canal. The current lock system has been in place for over 100 years, even though the size of ocean-going vessels has expanded considerably. One impact is on Panama’s maritime cluster. It is expected that the expansion will result in greater demand for many of the goods and services provided by the cluster. This article examines the economic impact of the Canal expansion on Panama’s maritime cluster. Clusters of economic activity can result in economies of agglomeration and supply chain network effects. Without these economies and network effects, clusters would not have a competitive advantage over businesses that are not in a cluster. It is expected that with a larger cluster, both agglomerative economies and network effects will increase. But, which cluster components will grow and which will not be affected to a great extent? To what extent will bottlenecks appear? These are some of the questions that this article addresses.  相似文献   
138.
This paper presents the results of applying DRAG methodology to the identification of the main factors of influence on the number of injury and fatal accidents occurring on Spain’s interurban network. Nineteen independent variables have been included in the model grouped together under ten categories: exposure, infrastructure, weather, drivers, economic variables, vehicle stock, surveillance, speed and legislative measures. Highly interesting conclusions can be reached from the results on the basis of the different effects of a single variable on each of the accident types according to severity. The greatest influence revealed by the results is exposure, which together with inexperienced drivers, speed and an ageing vehicle stock, have a negative effect, while the increased surveillance on roads, the improvement in the technological features of vehicles and the proportion of high capacity networks have a positive effect, since the results obtained show a significant drop in accidents.  相似文献   
139.
Abstract

Railways restructuring takes place under very different circumstances and with very different goals in Western Europe, Central and Eastern Europe, and Russia. There are some improvements in productivity associated with the reforms in the European Union (among others access to infrastructure and vertical separation). But they are not certain to be replicated following similar restructuring in transition economies, especially if one takes account of the much higher shadow price on government subsidies in the latter. The current and proposed reforms in the railways of Central and Eastern Europe and Russia are described in detail; the likely outcomes of reforms in the special economic, regulatory and legal environments of these countries are analysed; and an alternative proposal for restructuring in Russia is presented.  相似文献   
140.
Of the many public initiatives used to promote the use of bicycles in the urban environment, the one that has achieved the most spectacular results in a short period of time is the public bicycle hire system. The experience of Seville is one of the most successful internationally, where 6.6 % of mechanised trips were being made by bicycle within 30 months. This paper analyses this experience in the university community, which represents one-third of system users. We conclude that the people who are most satisfied with the system are those who use it for leisure and recreation activities, non-residents of the city, more environmentally aware people and those who have no alternative mode of transportation. Their satisfaction is also closely linked to their appreciation of the bicycles’ level of comfort, the ease with which users can hire bicycles and return them and the small amount of paperwork involved required to sign up for the system. However, user appreciation has fallen over time because the system’s rapid success has caused it to become overloaded. This experience therefore provides one main lesson: the system’s success can result in eventual difficulties.  相似文献   
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