全文获取类型
收费全文 | 5225篇 |
免费 | 641篇 |
专业分类
公路运输 | 1917篇 |
综合类 | 1998篇 |
水路运输 | 556篇 |
铁路运输 | 690篇 |
综合运输 | 705篇 |
出版年
2025年 | 29篇 |
2024年 | 76篇 |
2023年 | 81篇 |
2022年 | 122篇 |
2021年 | 171篇 |
2020年 | 201篇 |
2019年 | 131篇 |
2018年 | 168篇 |
2017年 | 191篇 |
2016年 | 244篇 |
2015年 | 261篇 |
2014年 | 467篇 |
2013年 | 370篇 |
2012年 | 431篇 |
2011年 | 467篇 |
2010年 | 354篇 |
2009年 | 335篇 |
2008年 | 321篇 |
2007年 | 389篇 |
2006年 | 325篇 |
2005年 | 208篇 |
2004年 | 104篇 |
2003年 | 71篇 |
2002年 | 49篇 |
2001年 | 94篇 |
2000年 | 36篇 |
1999年 | 30篇 |
1998年 | 21篇 |
1997年 | 29篇 |
1996年 | 15篇 |
1995年 | 10篇 |
1994年 | 16篇 |
1993年 | 10篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1988年 | 8篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有5866条查询结果,搜索用时 0 毫秒
71.
72.
73.
Yao Cheng 《智能交通系统杂志
》2018,22(5):422-432
》2018,22(5):422-432
Conventional Transit Signal Priority (TSP) controls often reach the limitation for arterials accommodating heavy bus flows since the priority function can significantly increase delay at minor streets. Under such conditions, a proper signal progression plan that accounts for the benefits of buses may offer the potential to improve the reliability of bus operations and increase the bus ridership. This study proposes a bus-based progression model to reduce the delay of buses on local arterials. Given the cycle length and green splits at each intersection, the bus-based progression model, grounded on the same notion as conventional signal progression methods, considers the operational characteristics of transit vehicles, such as the impact of bus dwell time and the capacity constraints at bus stops. Also, to deal with the stochastic nature of dwell time, this study introduces additional constraints to maximize the percentage of buses which can stay within the green band after leaving bus stops. Taking an arterial with five intersections and three two-way bus stops as an example, this study applies VISSIM as an unbiased tool for model evaluation. The simulation results demonstrate that the proposed model can significantly reduce bus passenger delays and the average person delays for the entire arterial, compared with the conventional progression models. 相似文献
74.
This paper presents a stochastic characterization of highway capacity and explores its implications on ramp metering control at the corridor level. The stochastic variation of highway capacity is captured through a Space–Time Autoregressive Integrated Moving Average (STARIMA) model. It is identified following a Seasonal STARIMA model (0, 0, 23) × (0, 1, 0)2, which indicates that the capacities of adjacent locations are spatially–temporally correlated. Hourly capacity patterns further verify the stochastic nature of highway capacity. The goal of this paper is to study (1) how to take advantage of the extra information, such as capacity variation, and (2) what benefits can be gained from stochastic capacity modeling. The implication of stochastic capacity is investigated through a ramp metering case study. A mean–standard deviation formulation of capacity is proposed to achieve the trade-off between traffic operation efficiency and robustness. Following that, a modified stochastic capacity-constraint ZONE ramp metering scheme embedded cell transmission model algorithm is introduced. The numerical experiment suggests that considering capacity variation information would alleviate the spillback effect and improve throughput. Monte Carlo simulation further supports this argument. This study helps verify and characterize the stochastic nature of capacity, validates the benefits of using capacity variation information, and thus enhances the necessity of implementing stochastic capacity in traffic operation. 相似文献
75.
在回顾我国客车发展历程的基础上,阐述国家汽车产业管理政策及客车产品技术进步的一些认识,提出进一步强化强制性标准、提高客车安全性、重视动态试验研究的建议。 相似文献
76.
77.
78.
XML6155大型城市客车的设计与开发 总被引:1,自引:0,他引:1
介绍了XML6155大型城市客车的开发背景和主要配置,重点阐述了顶盖、空调风道、扶手、座椅及暖风设计,指出了XML6155大型城市客车降噪方案的技术创新点。 相似文献
79.
80.