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231.
This article presents an overview of trends relevant for the long-term development of Rotterdam's port complex and resulting opportunities for this complex. These trends resulted from a literature review and conversations with 20 professors in fields relevant for port development. Nine trends that can be expected to become increasingly important in the next decades are discussed. These trends include the rise of manufacturing and logistics platforms, higher land efficiency, increasingly mixed land use in port areas, and rising importance of a “regional innovation system” in ports. Opportunities and concerns for the port of Rotterdam resulting from the trends are discussed.  相似文献   
232.
This paper analyses the past, present and future of the maritime transportation industry in the Kingdom of Saudi Arabia. Saudi Arabian seaborne trade and the shipping capacity are analysed for the past 15 years. Relationships between the declining Saudi shipping capacity and other economic measures are identified. Analysis of the Saudi Arabian maritime transportation is performed with respect to the world carrier fleets and models are developed to determine the theoretical shipping capacity required for transportation of the national seaborne cargo. Forecasts of the future shipping capacity requirement for the Kingdom are also presented. This paper illustrates the general approach for analysing a country's maritime industry and thus could help other researchers in that respect.  相似文献   
233.
International shipping is a significant contributor to Global Greenhouse Gas (GHG) emissions, responsible for approximately 3% of global CO2 emissions. The International Maritime Organization is currently working to establish GHG regulations for international shipping and a cost effectiveness approach has been suggested to determine the required emission reductions from shipping. To achieve emission reductions in a cost effective manner, this study has assessed the cost and reduction potential for present and future abatement measures based on new and unpublished data. The model used captures the world fleet up to 2030, and the analysis includes 25 separate measures. A new integrated modelling approach has been used combining fleet projections with activity-based CO2 emission modelling and projected development of measures for CO2 emission reduction. The world fleet projections up to 2030 are constructed using a fleet growth model that takes into account assumed ship type specific scrapping and new building rates. A baseline trajectory for CO2 emission is then established. The reduction potential from the baseline trajectory and the associated marginal cost levels are calculated for 25 different emission reduction measures. The results are given as marginal abatement cost curves, and as future cost scenarios for reduction of world fleet CO2 emissions. The results show that a scenario in which CO2 emissions are reduced by 33% from baseline in 2030 is achievable at a marginal cost of USD 0 per tonne reduced. At this cost level, emission in 2010 can be reduced by 19% and by 24% in 2020. A scenario with 49% reduction from baseline in 2030 can be achieved at a marginal cost of USD 100 per tonne (27% in 2010 and 35% in 2020). Furthermore, it is evident that further increasing the cost level beyond USD 100 per tonne yield very little in terms of further emission reduction. The results also indicate that stabilising fleet emissions at current levels is obtainable at moderate costs, compensating for fleet growth up to 2030. However, significant reductions beyond current levels seem difficult to achieve. Marginal abatement costs for the major ship types are also calculated, and the results are shown to be relatively homogenous for all major ship types. The presented data and methodology could be very useful for assisting the industry and policymakers in selecting cost effective solutions for reducing GHG emissions from the world fleet.  相似文献   
234.
Some South African cities have initiated public transport transformation projects which, in most cases, ultimately envisage the in toto replacement of paratransit operations with formalised BRT systems. There are two likely outcomes: (1) complex negotiations with existing operators and budget constraints will result in the in toto transformation occurring over an extended period of time; or (2) in toto transformation will simply not occur. In either case, cities will depend, for decades, on a ‘hybrid’ public transport system that combines both formal and paratransit operators. This paper presents a case for policy recognition of hybrid systems, and explores how such systems might best be managed. The following categories of hybrid public transport systems are explored through case studies: (1) transformative processes in which paratransit operators are to form or assimilate into companies to operate new services, but this incorporation has proved difficult to complete and the operational and regulatory frameworks remain unchanged; and (2) transformative processes that, from the outset, anticipated a hybrid system and designed the outcome accordingly. A third category of hybrid transport systems, defined as transformative processes that have been amended following a realisation that in toto transformation is unattainable, is also introduced and discussed. The paper concludes by tentatively drawing lessons for appropriate public transport regulation, particularly with respect to Cape Town's transformation project. It is argued that a review of the current national regulatory framework is required to enable possible project modifications that acknowledge system hybridity. It is suggested that regulatory frameworks that accommodate the likely hybrid nature of public transport system outcomes have greater prospects of success than frameworks that do not. Furthermore, it is argued that contextually appropriate and successful public transport transformation projects do not necessarily require the in toto substitution of incumbent paratransit operators, and that they can be integrated with, and complement, formal services.  相似文献   
235.
This paper highlights some of the difficulties involved in the implementation of complex cost structures in the tree-building section of a transport demand model. The conventional tree-building algorithm is briefly described and is seen to be inadequate for the present purpose. A new algorithm is then presented which is able to implement complex cost structures properly. An example is given of the application of this algorithm to the building of tree in a public transport network. The performance of a computer program incorporating the new alrogrithm is evaluated against alternative methods of implementing complex cost structures. Some mention is then made of the vast range of potential uses for the new algorithm in the field of transport modelling and simulation.  相似文献   
236.
237.
Currently existing models of parking choice behaviour typically focus on the choice of types of parking spaces. Implicitly these models assume that motorists have a free choice in that spaces are available. The adaptive behaviour which they reveal when faced with congested parking spaces is not explicitly modelled. The aim of this paper is to contribute to the growing literature on parking choice modelling by developing and testing a stated choice model of adaptive behaviour of motorists who are faced with fully occupied parking lots. The findings of the analyses indicate that the model performs satisfactory as indicated by its goodness-of-fit and the fact that all significant parameters were in anticipated directions.  相似文献   
238.
从广域运输管理、进路控制、列车控制和通信系统4个方面,介绍了欧洲铁路通信信号系统的技术现状和发展。  相似文献   
239.
Abolition of the National Dock labour Scheme in July 1989 has intensified competition in Britian's ports and allowed the major port authorities and other port operators to restructure their operations and develop new investment plans. But the result has been to add to excess capacity in the industry and to porduce a 'zero-sum' process of traffic redistribution between Britain's driven largely by customer demands for lower charges.  相似文献   
240.
For efficient analysis it is important to choose the proper model that fits the problem that needs to be solved. This paper discusses three pragmatic simulation models for longitudinal behaviour of a passenger car tyre (Steady State, Transient and Rigid Ring) that may be used in e.g. an ABS simulation. The characteristics of the simulation models are evaluated using some simple simulations. Simulations with a quarter vehicle model that includes load transfer effects are carried out to determine the deviation in results between the mentioned tyre models for an ABS application. The results show that the Steady State model may only be used below 10 Hz and that the Transient model is valid up to about 30 Hz. The results from the ABS simulation with the Rigid Ring model are most reliable and are clearly different from the Steady State and Transient model, which indicates that ABS simulations should be carried out with the Rigid Ring model. Additionally it is demonstrated that for tyre behaviour on uneven roads the influence of the tyre belt cannot be neglected.  相似文献   
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