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991.
Abstract

This paper develops a Stated Preference (SP) experiment that provides a way to measure service quality in public transport. The paper introduces an empirical procedure for optimising the SP experiment. This procedure permits the identification of the choice alternatives defining the experiment by simulating the choices of a user sample. By using the data collected from an experimental survey, a Multinomial Logit model was calibrated. This model is a way of identifying the importance of service quality attributes on global customer satisfaction and calculating a Service Quality Index, which provides an operationally appealing measure of current or potential service effectiveness.  相似文献   
992.

This paper outlines the issues involved in the problem of global warming. The road transport sector's contributions to this problem are then detailed and various policy options to reduce greenhouse gas emissions from private cars are discussed. The paper then describes a model which forecasts greenhouse gas emissions from cars. The effects of various policy options are then modelled and the results compared. Policies considered include: raising fuel prices in terms of the UK government's commitment to increase road fuel duties; subsidising public transport in terms of reduced public transport fares; and a tax differentiated by engine size.  相似文献   
993.
Abstract

This paper provides a unifying framework to analyze whether a monopoly transit provider will under or over-supply frequency. To this end we couch the problem in term of Spence [(1975). Monopoly, quality and regulation. The Bell Journal of Economics, 6, 417–429] who analyzed the incentives to provide quality by a monopolist. We show that all of the results of a recent academic exchange discussing this topic are special cases of Spence [(1975). Monopoly, quality and regulation. The Bell Journal of Economics, 6, 417–429], albeit with an adjustment in order to take into account the cost structure of frequency provision in the case of public transport. In theory then, there are cases when a monopolist may offer optimal or above optimal levels of frequency without requiring subsidies. However, public transport is rarely provided by an unregulated monopolist. Rather, these services are usually provided either by an exclusive operator under regulated fares or by a group of competing operators, with or without fare regulation. We show that in the first case frequency will always be below the social optimal level.  相似文献   
994.
Abstract

Transport accounts for around a quarter of CO2 emissions globally. Transport modelling provides a useful means to explore the dynamics, scale and magnitude of transport-related emissions. This paper explores the modelling tools available for analysing the emissions of CO2 from transport. Covering a range of techniques from transport microsimulation to global techno-economic models, this review provides insights into the various advantages and shortcomings of these tools. The paper also examines the value of having a broad range of perspectives for analysing emissions from transport. The paper concludes by suggesting that the broad range of models creates a rich environment for exploring a spectrum of policy questions around the emissions from transport, and the potential for combining modelling approaches further enhances the understanding that can be attained.  相似文献   
995.
Abstract

There is a growing tendency in cities around the world to invest in Bus Rapid Transit (BRT) systems in an attempt to improve the capacity and quality of public transport services. The appeal of BRTs is based on their ability to combine the service level of rail transit systems with the flexibility of buses at relatively lower investment costs, and this was the motivation behind the opening of such a system in the Turkish city of Istanbul in 2007. This system has attracted mixed opinions as to its performance, as while passenger ridership figures are extremely high, proving the effectiveness of the system, there is an argument that the corridor should have been developed with rail technology, and that the BRT is failing to meet the demand. The paper presents a comprehensive analysis of this system, assessing its planning and performance through a comparative analysis of a number of BRTs in the world and Istanbul's metro and tram systems. The analysis confirms the success of the system in terms of passenger statistics, but also highlights a number of problems in certain planning decisions that should be addressed, thus taking the discussion beyond a simplified comparison of bus and rail technologies.  相似文献   
996.
Abstract

The paper presents a detailed comparative review of price/cost elasticity estimates published in a number of studies on multi-mode freight transport demands. It attempts to determine which factors could explain the wide diversity of estimates: data aggregation, diversity of markets, and methodology. It also presents new estimates for rail, road, and waterway modes, derived from a multimodal freight network model of the Rhine area market. Direct and cross-elasticities are estimated for 11 groups of commodities and per distance category. The results are critically assessed by comparison with the reviewed studies. The paper concludes with a few recommendations about meaningful uses of existing estimates and the need for additional experiments with different methodologies applied on a common data basis.  相似文献   
997.
Abstract

Statistical mechanics has shown its usefulness when assessing the topology of many networks, including those of infrastructure. Its principles take into account the large-scale and network-wide effects of changes in its key parameters, which in turn may provide critical input when planning for infrastructure projects. One objective would be to modify the pattern of capacity expansions inside a system to make it less exposed to local shortfalls in demand. To illustrate our point, we shall use domestic air traffic in China; airports are spatially distributed and they also need to respond to the potential demand that they face locally. Airlines that control parts of the traffic system are identified as agents. A relationship between the agent's behavior and the system-wide level of variance in traffic flows can be established by regression analysis. It is shown how intervention on these agents would reduce negative traffic variance while enhancing a more balanced, less costly growth of the system itself.  相似文献   
998.
Abstract

This paper presents a decision support methodology for long-range planning of transport systems that exhibits strategic flexibility and stochastic system parameters. Unlike one-off strategic decisions, flexible decisions should be dynamically reformulated with time. The proposed methodology is based on the construction of a tree structure of multiple interlinked tactical planning problems, each associated with a scenario in the tree, where problems under scenarios at intermediate dates incorporate in their formulation the solution of the corresponding problems associated with past (future) connected scenarios. The resulting tree structure of interconnected planning decisions becomes a strategic-tactical decision support system that allows managers to formulate suitable flexible strategic decisions that mitigate the consequences associated with downside scenarios while taking advantage of the upside opportunities. The methodology is applied to the planning of a fleet deployment through charter contracts where contract prices depend on both market behavior and the duration of the contract itself.  相似文献   
999.
针对城市客运枢纽间综合运输通道协同性欠缺、运输效率低等问题,提出考虑弹性需求的城市客运枢纽间多方式时刻表协同优化方法。基于多项Logit模型对枢纽间乘客出行方式选择行为进行建模,分析各方式时刻表变动对出行需求的影响;以乘客等待总时间,时刻调整总数量,时刻调整总时间最小为优化目标,考虑弹性需求、时间窗、容量限制等约束,构建枢纽间多方式时刻表协同优化模型,并基于非支配排序遗传算法,结合客流加载仿真过程设计模型求解算法;最 后,以“北京南站-北京首都国际机场”多方式通道为例检验模型的有效性。结果表明,时刻表优化方案的实施使各方式产生了较为明显的需求弹性变化效果,模型求解得到10种时刻表优化方案,其评价结果整体优于传统模型,最终筛选方案可缩短乘客等待时间10.36%。  相似文献   
1000.
针对典型的海岛型城市海口市,综合考虑经济、政策、基础设施等多维度定性、定量影响因素,构建系统动力学模型,预测2020-2035年海口市对外客运需求量。预测结果显示,未来15年海口市对外客运需求呈稳步上升趋势,预计在2035年对外客运总量将突破8000万人次。GDP敏感性分析结果表明,当增速大于9%时,当前设施建设计划需要进一步加强,提前提高交通设施的供给能力;就业引进人口敏感性分析得出,人才引进规模控制在100万人左右可实现最大的经济效益,比60万人、140万人分别高出6.9%、5.1%;两种主要对外交通方式(机场和高铁)建设时序敏感性分析结果表明,机场开通相比高铁可拉动需求增长提高6.3%,这充分说明航空是海岛型城市对外出行的主要方式。  相似文献   
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