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961.
This paper analyses the efficiency of 44 US airports for the period 2005–2009. In addition to the conventional outputs (i.e., passengers, flights and cargo), we consider three undesirable externalities of airport activities: delays, noise and local air pollution. We adopt a directional distance function approach and perform a second stage analysis to investigate potential determinants of efficiency. Our base case results with only the positive outputs show that the greater the average aircraft size serving an airport and the larger the dimensions of the airport, the higher the technical efficiency. However, our results are sensitive to the inclusion of the undesirable outputs. The implications are that the inclusion of these externalities into the calculation of efficiency may impact policy decisions.  相似文献   
962.
以辽宁省某高速公路一处视觉遮挡板设计为工程实例,详细介绍了对其进行结构计算和设计的过程,为类似工程提供参考。  相似文献   
963.
车道机是高速公路收费系统的重要组成部分,主要用于对高速公路车道收费系统以及相关外围设备采集的各种信号进行控制和处理。文章介绍了嵌入式一体化车道机所具备的功能及工作原理,阐述了其技术特性,并通过与传统人工收费车道机的对比,分析了嵌入式一体化车道机的应用优势与前景。  相似文献   
964.
The Asian region is considered as the most thriving region in terms of economic integration at present. Given the fact that most of the Asian countries’ commodity trade relies on maritime transport, its economic integration is expected to affect the shipping activities and consequently maritime CO2 emissions. This study develops a novel and systematic analysis on the key driving factors through which trade liberalization can influence maritime CO2 emissions. Our simulation results suggest that, depending on the level of Asian integration, global CO2 emissions may slightly fall (ASEAN+3 FTA) or even rise (ASEAN+6 FTA). The reason for the latter is that the “trade scale effect” (higher emissions due to a significant increase in trade among participating countries) outweighs the “trade structure effect” and “shipment type effect” (lower emissions as a result of an increase in intra-Asia trade and a change in commodity composition). Finally, all countries involved in the Asian integration, except Japan, will experience an increase in maritime CO2 emissions. In particular, a relatively significant increase in the maritime CO2 emissions occurs in the developing Asian countries owing to substantial trade scale effect after removing their relatively high trade barriers.  相似文献   
965.

The choice behaviour of low cost travel (LCT) modes is very sensitive to travel distance. A line haul system designed on the basis of current planning practice of locating widely spaced stations to cater auto and bus feeder modes with the primary objective of gaining travel speed is hostile to non‐motorized and low cost feeder modes. With the revival of interest in promoting the use of walk'n ride and bike'n ride modes, there is a need to develop an appropriate tool to examine the effect of their specific characteristics in establishing the number and location of stations.

A generic normative behavioural hybrid model for locating the cost minimizing number and location of stations is developed for an LCT‐fed line haul system. The model considers the system with many to many two dimensional line haul demand density function in which the density varies in both x‐ and y‐directions. The feeder mode choice behaviour is incorporated in the model by integrating probability‐access/egress distance function with the objective function. Explicit functional relationships among the parameters of these feeder modes such as modal share as a function of access/egress distance with the parameters of line haul systems are developed. Dynamic programming is used to minimize the system cost. The generic model is shown to collapse into several simplified models capable of yielding approximate solutions for several well known special cases. It has been shown that location of stations is sensitive to the through load on board as well as users’ cost that defines the choice behaviour at large. Numerical examples are presented to demonstrate the applicability of the model.  相似文献   
966.
This study analyzes the effects of demand uncertainty on airport capacity choices. It shows that demand uncertainty will not change optimal capacity choice if demand variation is low and capacity cost is high; otherwise the optimal airport capacity under demand uncertainty will be larger than the case when a deterministic mean demand is considered. These conclusions are robust with respect to the different market structures considered in this study and hold for both profit-maximizing and welfare-maximizing airports. The moderating effects of commercial revenue, capital cost, and airport operation cost on airport capacity choice are qualitatively the same in the cases of uncertain demand and deterministic demand.  相似文献   
967.
The combined impact of ownership form, economic regulation and competition on airport performance is analyzed using data envelopment analysis to measure cost efficiency in the first stage and regression analysis to measure the impact of the environment in the second stage. The empirical results of an analysis of European and Australian airports over a 10 year timeframe reveal that under relatively non-competitive conditions, public airports operate less cost efficiently than fully private airports. Irrespective of ownership form, regulation is necessary to emulate competitive forces thus pushing airport management towards cost efficiency and reasonable pricing policies. Under potential regional or hub competition, economic regulation inhibits airports of any ownership form from operating and pricing efficiently. Although public and fully private airports operate equally efficiently in a competitive setting, private airports still set higher aeronautical charges. Furthermore, mixed ownership forms with a majority public holding are neither cost efficient nor low price, irrespective of the level of competition.  相似文献   
968.
杜旭强  陈强 《北方交通》2012,(4):142-144
对高速公路管理局现有的与监控信息相关的数据进行整合,将整合信息定位到WEBGIS平台,面向管理决策、普通管理员、公众提供全面的运行数据和服务信息。  相似文献   
969.
郭筱穆 《北方交通》2012,(8):111-114
通过分析比较分车型收费和计重收费的优缺点,论证了载货类汽车收费方式转变的合理性,并在辽宁的实践应用中得以证实。  相似文献   
970.
This paper analyzes strategic interaction between intercontinental airport regulators, each of which levies airport charges paid by airlines and chooses its airport capacity under conditions of congestion. Congestion from intercontinental flights is common across intercontinental airports since departure and arrival airports are linked one to one, while purely domestic traffic also uses each airport. The paper focuses on two questions. First, if both continents can strategically set separate airport charges for domestic and intercontinental flights, how will the outcome differ from the first-best solution? Second, how is strategic airport behavior affected by the extent of market power of the airlines serving the intercontinental market? We see that strategic airport pricing and capacity choices by regulators lead to a welfare loss: the regulators both behave as monopolists in the market for intercontinental flights, charging a mark-up and decreasing capacity. This welfare loss even overshadows possible negative effects from imperfect competition within the intercontinental airline market. We further discuss how the presence of multiple regulators on one continent or a simple pricing rule might constrain the welfare loss created by strategic airport regulation.  相似文献   
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