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851.
A wide range of transport‐related decisions involve the linking of discrete choices (e.g. of vehicle choice) and continuous choices (e.g. of vehicle use). In recent years econometricians have developed procedures for integrating such choices into a framework that is both economically and statistically sound. The literature is however somewhat technical. The objective of this paper is to provide a general overview of the basic elements of discrete/continuous econometric modelling with an emphasis on transport applications. It is hoped that such an introduction will demonstrate that the essence of the approach for the practitioner is quite straightforward and can be implemented with widely available computer software. 相似文献
852.
J. A. Zerby 《Maritime Policy and Management》2013,40(4):241-251
The potential effects of a rigid adherence to the UNCTAD Code are analysed for 26 developing countries. A brief commentary is given on the advantages of a more liberal application of the Code, including reciprocal sharing of liner tonnages by regions of developing countries with regions of developed market-economy countries. 相似文献
853.
This study provided an examination of the alternative means used by Metropolitan Planning Organizations (MPOs) to carry out transportation planning activities in different areas of the U.S.A. This has been done by first developing a general profile of the nature and functions of the MPOs in the 100 largest regions in the U.S. and by an in‐depth analysis of seven regions. The purpose of these activities was to examine similarities and differences between MPOs and to identify factors that appear to lead to the effectiveness or non‐effectiveness of MPOs in different areas. From the analysis, it is evident that there are wide differences between MPOs in their organization, function, and degree of effectiveness in carrying out transportation planning. These differences do not appear to be related to any structural characteristics of MPOs, but rather are the result of past history and the attitudes of people involved. 相似文献
854.
This paper explores the relative influence of factors affecting light rail ridership on 57 light rail routes in Australia,
Europe and North America through an empirical examination of route level data. Previous research suggests a wide range of
possible ridership drivers but is mixed in clarifying major influences. A multiple-regression analysis of route level ridership
(boardings per route km) and catchment residential and employment density, car ownership, service level, speed, stop spacing,
share of accessible stops, share of segregated right of away and integrated fares was undertaken. This established a statistically
significant model (99% level, R2 = 0.76) with five significant variables including service level, routes being in Europe, speed, integrated ticketing and
employment density. In general these findings support selected results from previous research. A secondary analysis of service
effectiveness measures (boardings/vehicle km, i.e. the relative ridership performance for a given level of service), established
a statistically significant model (99% level, R2 = 0.67) with 6 significant explanatory variables including being in Europe, speed, employment density, integrated ticketing,
track segregation and service level. The latter implies that a higher frequency results in higher service effectiveness. Overall
the research findings stress the importance of providing a high level of service as a major driver of light rail ridership.
The ‘European Factor’ is also an important though intriguing influence but its cause remains unclear and requires further
research to elaborate its nature. 相似文献
855.
It is the aim of the European Union to develop a transport policy that supports its economic and sustainable growth and where the concept of sustainable mobility is a driver in the development of such policy. To achieve this goal, the European Union (EU) is promoting the shift of goods to unused existing capacity in rail and sea modes. As such, it is the objective of this paper to carry out a review of the European shipping policy at a time when the EU Member-States are suffering from high levels of congestion, noise and pollution that not only affect the environment but also the quality of life of all citizens. This paper considers the development of EU shipping policy in three stages. 相似文献
856.
Transportation - City events are getting popular and are attracting a large number of people. This increase needs for methods and tools to provide stakeholders with crowd size information for crowd... 相似文献
857.
We propose a fuzzy logic control for the integrated signal operation of a diamond interchange and its ramp meter, to improve traffic flows on surface streets and motorway. This fuzzy logic diamond interchange (FLDI) comprises of three modules: fuzzy phase timing (FPT) module that controls the green time extension of the current phase, phase logic selection (PLS) module that decides the next phase based on the pre‐defined phase sequence or phase logic and, fuzzy ramp‐metering (FRM) module that determines the cycle time of the ramp meter based on current traffic volumes and conditions of the surface streets and the motorways. The FLDI is implemented in Advanced Interactive Microscopic Simulator for Urban and Non‐Urban Network Version 6 (AIMSUN 6), and compared with the traffic actuated signal control. Simulation results show that the FLDI outperforms the traffic‐actuated models with lower system total travel time, average delay, and improvements in downstream average speed and average delay. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
858.
David A. Hensher Anne Yvrande‐Billon Rosário Macário John Preston Peter White Bill Tyson 《运输评论》2013,33(4):411-448
Abstract This paper documents some thoughts on the reform agenda in public transit that is occurring throughout the world. The specific focus is on a growing commitment to competitive regulation through competitive tendering, and the efforts by a few governments (notably in Australia) to take control of the tangible assets used by private operators as a mechanism to exercise the opportunity, if so taken, to put services out to competitive tender. The paper reviews the theoretical arguments and empirical evidence on contracting regimes and asset ownership, and the role that government and the operator might play in a setting in which building trusting and collaborative partnerships has merit in delivering services that are in the main funded from the public purse. 相似文献
859.
In Hong Kong the high cost of land reclamation servicing has made it necessary to plan land use through zoning commercial and industrial activity and by adopting very high densities for residential accommodation. Traffic has concentrated along particular corridors where its volume now exceeds road capacity. The imperative development of an urban rail system has affected the economic stability of most public transport. Simultaneously, private motoring has increased so rapidly that fiscal restraints have been imposed, generating a serious proposal for electronic road pricing. The future growth of links with China will end Hong Kong's relative isolation and present new transport planning challenges. 相似文献
860.
The aim of this work is to analyze the hydroacoustic behavior of a marine propeller through the acoustic analogy and to test the versatility and effectiveness of this approach in dealing with the many (and relatively unexplored) issues concerning the underwater noise and its numerical prediction. In particular, a propeller in a noncavitating open water condition is examined here by coupling a Reynolds averaged Navier–Stokes hydrodynamic solver to a hydroacoustic code implementing different resolution forms of the Ffowcs Williams–Hawkings (FWH) equation. The numerical results suggest that unlike the analogous aeronautical problem, where the role played by the nonlinear quadrupole sources is known to be relevant just at high transonic or supersonic regime, the pressure field underwater seems to be significantly affected by the flow nonlinearities, while the contribution from the linear terms (the thickness and loading noise components) is dominant only in a spatially very limited region. Then, contrary to popular belief and regardless of the low blade rotational speed, a reliable hydroacoustic analysis of a marine propeller cannot put aside the contribution of the nonlinear noise sources represented by the turbulence and vorticity three-dimensional fields and requires the computation of the FWH quadrupole source terms. 相似文献