首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   673篇
  免费   3篇
公路运输   232篇
综合类   22篇
水路运输   223篇
铁路运输   23篇
综合运输   176篇
  2023年   4篇
  2022年   12篇
  2020年   6篇
  2019年   14篇
  2018年   20篇
  2017年   14篇
  2016年   27篇
  2015年   11篇
  2014年   29篇
  2013年   100篇
  2012年   33篇
  2011年   37篇
  2010年   36篇
  2009年   31篇
  2008年   27篇
  2007年   14篇
  2006年   13篇
  2005年   11篇
  2004年   10篇
  2003年   7篇
  2002年   14篇
  2001年   11篇
  2000年   12篇
  1999年   4篇
  1998年   13篇
  1997年   7篇
  1996年   15篇
  1995年   9篇
  1994年   4篇
  1993年   4篇
  1992年   6篇
  1991年   7篇
  1990年   4篇
  1989年   7篇
  1988年   10篇
  1987年   5篇
  1986年   5篇
  1985年   4篇
  1984年   7篇
  1983年   4篇
  1982年   3篇
  1981年   11篇
  1980年   3篇
  1979年   14篇
  1978年   5篇
  1977年   7篇
  1976年   6篇
  1975年   3篇
  1974年   3篇
  1973年   8篇
排序方式: 共有676条查询结果,搜索用时 15 毫秒
71.
Although considerable progress has recently been made in the evolution of marine traffic procedures in coastal and waterway areas, mariners are finding difficulty in coping with the diverse traffic schemes that have so far been devised. This paper is a plea for international and logical marine traffic management, so that ships can operate safely and efficiently within a framework of the proliferating offshore zonal legislation that we are now witnessing.  相似文献   
72.
This is one of two papers designed to test the ability of a theoretical model of productivity measurement [1] with times series empirical data. The analysis was able to identify trends in productivity growth for sailing ships and stcamships. scparating long and short run components . One of the interesting features of the findings is that the long run growth rate is the same for both sailing and steamships. Although sail and steam appear to be two unique technologies, it is found that technologica progress is evolutionary not revolutionary.

The techique using covariance analysis proved useful for times series productivity measurement.  相似文献   
73.
A new assignment principle for traveler behavior in an urban network is described which is based on empirical findings in the theory of travel budgets. It characterizes the distribution of travelers, demand, and modal split. It treats all travel decisions (whether to travel, where to go, how to get there) and the important costs (time and money) in a single, unified way. A numerical technique is proposed and it is applied to several examples to illustrate qualitative features.  相似文献   
74.
To plan new bus routes in suburban areas, expected bus running times on these routes are needed. Using most readily available relevant variables, a regression model is developed for estimating bus running times. The model is conceptually reasonable and it was tested using data other than that used for estimation.  相似文献   
75.
76.
Due to the capital-intensive nature of the modern shipping industry, loan finance plays a major role in vessel-acquisition cost. In this paper, J. B. Yolland discusses government-guaranteed finance, ancillary and commercial new building finance and finance for second-hand tonnage. He also examines a new source of funding found in the Euro-market.  相似文献   
77.
78.
This paper presents a novel user-equilibrium (UE) traffic assignment algorithm, which under conventional assumptions, promises to compute UE arc flows to acceptable precision, regardless of the network’s topology, size or congestion:
• The algorithm takes the simple approach of shifting flow from a costliest path to a cheapest path until the costs of all used paths are within a given of the cheapest.
• Because of being path-based, it avoids tailing.
• In spite of being path-based, it neither stores nor enumerates paths.
• These efficiencies derive from decomposing the problem into a sequence of easy single-origin problems on acyclic sub-networks.
Solutions to this sequence of sub-network flows converge rapidly to a sharp practical estimate of UE arc flows—as is amply demonstrated by tests using the Chicago region’s 40,000-arc network model.  相似文献   
79.
A particular parameter estimability problem in the multinomial probit model is considered. Making use of a model discussed in the literature, some problems with the usual method of specification are discussed. Some general comments are made on the problem of selecting a normalisation when using the multinomial probit model.  相似文献   
80.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号