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331.
MUHAMMAD F. IBRAHIM 《运输评论》2013,33(2):221-243
A review of the retailing and transportation literature shows that there is an apparently large research gap in the understanding of shoppers’ attitudes towards transport modes for shopping purposes. In particular, not many studies have been done to examine shoppers’ detailed and disaggregated attitudinal image structures of the various transport modes for shopping purposes. Using Singapore as a study area, this paper has attempted to investigate shoppers’ image structure of transport modes and their comparative perception ratings for the various modes of transportation for shopping purposes. Using principal component analysis, the research has unveiled the perceptions of five transport modes for shopping purposes. While some of the factors are unique to certain transport modes, other factors, namely ‘suitability’, ‘practicality’, ‘ease of travel’ and ‘cost’, are common to all modes of transportation. By way of the weighted‐factor rating, the study found that the car recorded the highest overall perception rating while the bus rated the lowest. In addition, the shoppers have reasonably good perception of public transport modes in Singapore. 相似文献
332.
In 1991, the Aquaculture Department of the Southeast Asian Fisheries Development Center launched a community-based fishery resources management project on Malalison Island, in central Philippines, to help conserve the country's marine resources and to help the fisherfolk rise above their poverty. The eight-year project integrated various disciplines in biology, economics, sociology, public administration, and engineering in its study of fishery resources and fishing communities and in evolving intervention strategies for resource conservation and management, and for community development. The project's most important accomplishment was the inculcation among the fisherfolk of the importance of resource conservation and management. The most important lesson learned was that an enlightened and empowered fisherfolk could be effective managers and responsible users of fishery resources. 相似文献
333.
S. J. Ahn 《International Journal of Automotive Technology》2010,11(6):909-916
Shock-type vibrations are frequently experienced in vehicles excited by impulsive input, such as bumps in the road, and cause
discomfort. Current national and international standard weightings were primarily developed for assessing exposure to sinusoidal
or random vibrations and not impulsive excitations or shocks. In this experimental study, various shock signals were systematically
produced using the response of a one degree-of-freedom vibration model to hanning-windowed half-sine force input. The fundamental
frequency of the shock was varied from 0.5 to 16 Hz at a step of 1/3 of an octave. The magnitude estimation method was used
for fifteen subjects to compare the discomfort of shocks with various unweighted vibration dose values between 0.35 ms−1.75 and 2.89 ms−1.75 at each frequency. The equivalent comfort magnitude of shock showed greater sensitivity at frequencies less than 0.63 Hz
and at the resonance frequency of the human body between 5.0 Hz and 6.3 Hz. The frequency weighting constructed by using both
the equivalent comfort magnitude and the growth rate of discomfort obtained in this study was compared with the current standard
weightings, Wb of BS 6841 and Wk of ISO 2631. The derived weightings for shock were applied to the acceleration of the shocks, and an enhanced correlation
was proved between the magnitude estimations and the weighted physical magnitude of shock. 相似文献
334.
J.P.M. Hendrikx T.J.J. Meijlink R.F.C. Kriens 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1996,26(6):449-461
The application of Optimal Control Theory to time-optimal inverse simulation of car handling was investigated. Time-optimal inverse simulation of car handling involves the calculation of driver actions required to perform specified manoeuvres, in as short a time as possible. Driver actions consist of time-histories of front wheel steer rate and longitudinal force. Optimal time-histories of these quantities were calculated using the Gradient method after formulating the problem as one of optimal control. Simulation results are presented for two different cars performing similar lane-changes. These results show significant differences in necessary driver actions for different cars and demonstrate the suitability of the approach taken. 相似文献
335.
P F Stratton D Ho Saxena . BOC Gases European Development Centre Rother Valley Way Holbrook Sheffield S RP UK. . The HOC Group Technical Centre Mountain Avenue Murray Hill New Jersey - USA 《上海交通大学学报(英文版)》2000,(1)
1ntroductionGaswimpfobe,usuallynitrOgen,mandheiumatposuresOfuPtO60barhasbousedinvacmbosfOrSendywtanditScharWshcsforbds-ofCOInNarewe1knOWUIl].More~theuseofgasq-aPPliedtOs~orsinglelayereOfCOmwtthawereheandindsvacuumorCOnwtalatmOSPherbohasboPrOpond(2l.TOathaatetheedtOCOOtheboacestruCtUrasweIIastheCOIntwIkeSechquesOboinvolvethetrareferOftheNttobeqMtoa~allydeaignedcoklchfortsl.6as~of~peinndsngmaybosoaS~the-ofbo'bds-Oha'pesstwfOr'juSb~'manwt.Unlikliquldbased~antS,gaswiiscleannO… 相似文献
336.
A moving bottleneck 总被引:1,自引:0,他引:1
G.F Newell 《Transportation Research Part B: Methodological》1998,32(8):531-537
Suppose that a vehicle or convoy enters a two-lane unidirectional roadway and travels at a velocity v* less than the prevailing traffic. This moving bottleneck may cause a queue to form as vehicles try to pass the obstruction. It is shown that by going to a moving coordinate system traveling at velocity v* the analysis of this can be transformed into a corresponding analysis of flow past a stationary bottleneck. The theory is then extended to investigate possible consequences of trucks on grades. 相似文献
337.
G.F. Newell 《Transportation Research Part B: Methodological》1998,32(8):583-588
—Suppose that in an office building of moderate height (5 to 20 floors) elevator traffic during peak periods is predominantly between a lobby floor and various upper floors. We compare the waiting plus riding time and the average number of passengers carried per trip for various strategies. In particular, if two (or more) elevators serve the same group of floors (a common strategy), the waiting plus riding time would typically be (slightly) less if one split the group into two parts and had each elevator serve separate parts of this group. The latter strategy would have considerably fewer passengers per trip. It may also be advantageous to have a single elevator serve different floors on successive trips. Seldom would it be advantageous for an elevator to serve more than 2 or 3 floors on any trip. If elevator systems used more efficient strategies during peak periods, buildings would not need as many elevators. 相似文献
338.
Short-line railroad managers discuss their industry 总被引:1,自引:0,他引:1
Johnson James C. McClure Diane J. Schneider Kenneth C. Wood Donald F. 《Transportation》2004,31(1):97-123
In the United States, the 1980 Staggers Rail Act created a positive regulatory environment for the creation of new short-line railroads. At present there are about 450 of these railroads that have less than 250 miles of trackage. This study asked managers/owners of these railroads two basic questions. First, what do you believe is the single most important trend that is currently taking place in your industry. The most frequently noted trend was the frustration of working with the larger Class 1 railroads. Five additional trends were also identified by the respondents. The second question asked the respondents if they thought the short-line sector of the rail industry will become more or less important in the next ten years and why. About 70% of the owner/managers believed their industry would become more important in the next decade. The most commonly expressed reason for this position is that the Class 1 railroads will increasingly specialize in mainline service only. Three other rationales were also enumerated. For the managers that thought their industry would become less important, the most noted reason was their trackage would not safely transport the newer very heavy bulk commodity freight cars. 相似文献
339.
Mass transit projects are often a top contender of many cities to meet their increasing demand for travel. Despite the global
trend of privatization, mass transit services, as public goods, remain largely being provided and operated by the public sector.
Hong Kong is one of the few exceptions that all mass transit services are commercially operated. Both rail and bus services
in Hong Kong are reputable for their quality and profitability, often serving as benchmarks for new projects. In this study,
we investigate the factors contributing to this success. In particular, we ascertain the quality of transit service provision
by the private sector over the past two decades. Then, we conduct an in-depth analysis of the account books of leading railway
and bus operators in Hong Kong so as to shed light on their financial viability. Through this study, we hope to present crucial
factors for providing financially viable private transit services. 相似文献
340.
This paper seeks to explore the relationship between mode and destination choice in an integrated nested choice model. A fundamental
argument can be made that in certain circumstances, the ordering of choices should be reversed from the usual sequence of
destination choice preceding mode choice. This results in a travel demand model where travelers are more likely to change
destinations than to change transportation modes. For small and medium size urban areas, particularly in the United States,
with less well developed public transit systems that draw few choice riders, this assumption makes much more sense than the
traditional modeling assumptions. The models used in the new travel modeling system developed for Knoxville, Tennessee utilize
this reversed ordering, with generally good results, which required no external tinkering in the logsum parameters. 相似文献