全文获取类型
收费全文 | 3175篇 |
免费 | 30篇 |
专业分类
公路运输 | 1054篇 |
综合类 | 122篇 |
水路运输 | 932篇 |
铁路运输 | 113篇 |
综合运输 | 984篇 |
出版年
2023年 | 24篇 |
2022年 | 68篇 |
2021年 | 28篇 |
2020年 | 24篇 |
2019年 | 29篇 |
2018年 | 97篇 |
2017年 | 78篇 |
2016年 | 137篇 |
2015年 | 42篇 |
2014年 | 122篇 |
2013年 | 464篇 |
2012年 | 152篇 |
2011年 | 166篇 |
2010年 | 150篇 |
2009年 | 149篇 |
2008年 | 145篇 |
2007年 | 83篇 |
2006年 | 69篇 |
2005年 | 85篇 |
2004年 | 52篇 |
2003年 | 55篇 |
2002年 | 46篇 |
2001年 | 45篇 |
2000年 | 64篇 |
1999年 | 43篇 |
1998年 | 41篇 |
1997年 | 51篇 |
1996年 | 47篇 |
1995年 | 67篇 |
1994年 | 31篇 |
1993年 | 40篇 |
1992年 | 24篇 |
1991年 | 21篇 |
1990年 | 20篇 |
1989年 | 16篇 |
1988年 | 21篇 |
1987年 | 24篇 |
1986年 | 24篇 |
1985年 | 31篇 |
1984年 | 30篇 |
1983年 | 30篇 |
1982年 | 31篇 |
1981年 | 40篇 |
1980年 | 26篇 |
1979年 | 42篇 |
1978年 | 19篇 |
1977年 | 30篇 |
1976年 | 22篇 |
1975年 | 24篇 |
1974年 | 14篇 |
排序方式: 共有3205条查询结果,搜索用时 15 毫秒
991.
R. L. Cosgriff H. H. Yeh 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1975,4(4):249-271
The dynamic shuttle system treated in this paper consists of main line trains traveling at a fixed speed. Passengers are shuttled to and from these fixed speed trains by means of shuttle cars. The shuttle cars can provide local service and thus alleviating the need for stations along the route of the main line trains. The main line trains have a peak volume, depending upon operating speed which is an order of magnitude greater than existing modes. They provide high speed service to travelers in the belt traversed by the trains. 相似文献
992.
993.
Irwin P. Levin 《Transportation》1982,11(1):71-85
In each of two experiments evaluations were obtained of alternative carpooling situations varying in driving arrangement, size of carpool, distance traveled, and amount of time to pick up and deliver passengers. College students in Experiment I rated each situation in terms of comfort, economy, convenience and overall desirability. Shared driving emerged as the most desirable driving arrangement, and results suggested that this was due to a tradeoff of the perceived economic advantages of being the driver and the perceived greater comfort and convenience of being a rider. Driving all the time was the least preferred arrangement for females, and riding all the time was the least preferred arrangement for males. Desirability ratings decreased as carpool size increased, and this was interpreted to indicate that perceived economic advantages of large pools were outweighed by large perceived decreases in comfort and convenience. The major results of Experiment I were replicated in Experiment II, using university employees who were either currently in carpools or seeking to find carpools. Results are discussed in terms of the practical implications of the findings concerning driving arrangement and carpool size preferences, and in terms of the usefulness of controlled experimental designs for understanding the processes-underlying ride-sharing attitudes and behavior. 相似文献
994.
995.
996.
Manisha H. Perera 《先进运输杂志》1992,26(1):9-23
The public and private bus sectors are in direct competition in most bus routes in Sri Lanka. Consequently, Sri Lanka is an ideal location to study their relative efficiencies. Five dimensions of transit performance are analyzed for comparing the relative efficiencies of the two sectors: cost efficiency, labour efficiency, input efficiency, revenue generation and safety. Productivity ratios are utilized for measuring the dimensions of transit performance. The productivity ratios for cost efficiency, labour efficiency in terms of total staff, input efficiency, revenue generation and safety in terms of accidents per bus showed the private bus transport sector to be more efficient than the public bus transport sector. 相似文献
997.
998.
999.
1000.
This paper explains the need for the application of cost-benefit analysis to the evaluation of alternative projects for investment in the transport field and outlines briefly the historical development of the technique. The results of a comparative survey of a number of cost-benefit studies which have been carried out in Britain and some conclusions as to their thoroughness and comprehensiveness (or otherwise) are presented. The article concludes with a number of specific and detailed recommendations to remedy apparent methodological weaknesses. Six of these recommendations seem to merit particular attention:
- The viewpoint of most studies should be extended so as to avoid confinement, for example, within an arbitrary local government boundary, and a wider range of “externalities” should be considered. Intangibles should be included explicitly in all such evaluation exercises.
- The actual incidence of costs and benefits should be examined in order to indicate the directional impact of the project and its implications in terms of equity. The elimination of transfer payments and double-counting should be postponed until the latest possible stage in the evaluation.
- Equity considerations should be investigated in any transportation plan, since most projects have considerable equity implications for particular areas or socio-economic groups.
- Discounted cash flow techniques, which are still used only in a minority of transportation studies, should become standard practice. Most evaluations are based on a single-year rate of return, or at best on simple trend forecasting. More resources should be devoted to proper evaluation of alternative plans which give due importance to the cost and benefit streams through time.
- Sensitivity analysis should be used in all transportation evaluations. Knowledge of the impact of different assignments, shadow prices, and discount rates are essential information for any decisionmaker.
- Last, but not least, much greater communication should exist between analyst and decisionmaker than has existed in the past.