全文获取类型
收费全文 | 3262篇 |
免费 | 67篇 |
专业分类
公路运输 | 1106篇 |
综合类 | 565篇 |
水路运输 | 796篇 |
铁路运输 | 419篇 |
综合运输 | 443篇 |
出版年
2023年 | 12篇 |
2022年 | 47篇 |
2021年 | 84篇 |
2020年 | 64篇 |
2019年 | 27篇 |
2018年 | 79篇 |
2017年 | 93篇 |
2016年 | 189篇 |
2015年 | 65篇 |
2014年 | 86篇 |
2013年 | 210篇 |
2012年 | 205篇 |
2011年 | 279篇 |
2010年 | 282篇 |
2009年 | 207篇 |
2008年 | 262篇 |
2007年 | 251篇 |
2006年 | 191篇 |
2005年 | 126篇 |
2004年 | 67篇 |
2003年 | 42篇 |
2002年 | 39篇 |
2001年 | 64篇 |
2000年 | 42篇 |
1999年 | 22篇 |
1998年 | 35篇 |
1997年 | 28篇 |
1996年 | 28篇 |
1995年 | 28篇 |
1994年 | 12篇 |
1993年 | 13篇 |
1992年 | 6篇 |
1991年 | 14篇 |
1989年 | 11篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 8篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1977年 | 11篇 |
1976年 | 6篇 |
1975年 | 7篇 |
1974年 | 6篇 |
1973年 | 7篇 |
1972年 | 4篇 |
排序方式: 共有3329条查询结果,搜索用时 109 毫秒
91.
92.
Maren L. Outwater Greg Spitz John Lobb Margaret Campbell Bhargava Sana Ram Pendyala William Woodford 《Transportation》2011,38(4):605-623
This research seeks to improve the understanding of the full range of determinants for mode choice behavior and to offer practical
solutions to practitioners on representing and distinguishing these characteristics in travel demand forecasting models. The
principal findings were that the representation of awareness of transit services is significantly different than the underlying
assumption of mode choice and forecasting models that there is perfect awareness and consideration of all modes. Furthermore,
inclusion of non-traditional transit attributes and attitudes can improve mode choice models and reduce bias constants. Additional
methods and analyses are necessary to bring these results into practice. The work is being conducted in two phases. This paper
documents the results of Phase I, which included data collection for one case study city (Salt Lake City), research and analysis
of non-traditional transit attributes in mode choice models, awareness of transit services, and recommendations for bringing
these analyses into practice. Phase II will include data collection for two additional case study cities (Chicago and Charlotte)
with minor modifications based on limitations identified in Phase I, additional analyses where Phase I results indicated a
need, and a demonstration of the research in practice for at least one case study city. 相似文献
93.
Y.H. Venus Lun Michael BrowneKee-hung Lai Christina W.Y. WongT.C.E. Cheng 《Research in Transportation Economics》2011,32(1):64-70
Container shipping and its related service sectors help accelerate globalization of the world economy. This industry has been experiencing rapid growth, prompting container terminal operators to increase their handling capacity in response. Providing container terminal services requires substantial capital investment in physical assets such as cargo handling facilities and information systems. On the other hand, operating container terminals is a long-term investment that typically spans several business cycles. Hence prudent asset management using appropriate tools is critical for container terminal operators to sustain their businesses. Generally, due to risk-adverseness, investors are unwilling to take more risk in their investment unless they can reap a higher return. Contrary to this argument, this study finds no direct influence of better firm performance as a proxy of higher return on business risk-taking by container terminal operators. Instead, scale of operations is positively associated with business risk-taking, suggesting that container terminal operators with a larger scale of operations are willing to take more business risk. 相似文献
94.
Nicole A. Costa Jeanette J. Jakobsen Reto Weber Monica Lundh Scott N. MacKinnon 《WMU Journal of Maritime Affairs》2018,17(4):521-542
The aim of this study was to assess proof of concept and usability of a maritime service website prototype in a full-mission ship bridge simulator through Swedish mariners’ experiences and perceptions. This test was part of the European Commission’s EfficienSea2 project for e-navigation. The prototype was intended as an aid to existing standard systems and methodologies for planning, executing and monitoring voyages. The study began with 5 days of simulator trials focused on today’s standard practices. This served as a baseline to compare to subsequent 4 days of simulator trials testing the prototype. For data collection, observations, video footage, interviews, and eye tracking were used. Data analysis included breaking apart the qualitative data to capture the perceptions of the participants, and a preliminary analysis of eye-tracking data as a complement. The results suggested that the prototype could be more suitable for a route planning stage, that the participants were familiar with similar existing solutions from other manufacturers, and that the contents of the tool would be most beneficial if integrated within the Electronic Chart Display and Information Systems (ECDIS). There is a pressing need for the novel solutions to be user needs-driven, integrated with the existing technologies, and standardized across the domain, and these processes must go hand-in-hand with accounting for all involved stakeholders, procedures, regulations, and training, as this will alter the course of shipping. 相似文献
95.
交叉口协调感应信号控制 总被引:1,自引:0,他引:1
介绍了传统的感应控制方法,着重对协调感应信号控制的基本原理,控制过程等进行了分析,并提出了解决问题的方法。分析了定时信号控制和感应信号控制的优缺点,对感应信号控制的进一步研究提出了几点看法。 相似文献
96.
利用太沙基单向固结理论,按照多级加载路堤沉降的叠加原理,建立非线性规划模型。用沉降实测资料确定模型参数,确定最优化模型后预测任意时刻沉降量。最后,用工程实例说明其方法在预测提前量上具有明显优势,是一种有效而实用的沉降早期预测方法。 相似文献
97.
98.
丰田汽车公司开发的FCHV-4型采用燃料电池和辅助电池作为混合动力系统的能源,极大提高能源转换效率,使汽车具有良好的性能。燃料电池与牵引电机逆变器直接相连,与辅助电池和DC/DC器串联。该燃料电池汽车的效率为传统内燃机汽车的3倍。 相似文献
99.
100.
预应力混凝土连续刚构悬臂施工的几点看法 总被引:1,自引:0,他引:1
引入应力集中的概念,分析挂篮施工的安全问题、受力预埋件焊接情况和结构物混凝土开裂问题,为类似工程的安全、质量控制提供参考. 相似文献