全文获取类型
收费全文 | 547篇 |
免费 | 28篇 |
专业分类
公路运输 | 125篇 |
综合类 | 71篇 |
水路运输 | 77篇 |
铁路运输 | 296篇 |
综合运输 | 6篇 |
出版年
2022年 | 16篇 |
2021年 | 21篇 |
2020年 | 22篇 |
2019年 | 14篇 |
2018年 | 4篇 |
2017年 | 9篇 |
2016年 | 11篇 |
2015年 | 21篇 |
2014年 | 63篇 |
2013年 | 39篇 |
2012年 | 57篇 |
2011年 | 46篇 |
2010年 | 41篇 |
2009年 | 43篇 |
2008年 | 29篇 |
2007年 | 24篇 |
2006年 | 29篇 |
2005年 | 24篇 |
2004年 | 21篇 |
2003年 | 14篇 |
2002年 | 8篇 |
2001年 | 1篇 |
2000年 | 7篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有575条查询结果,搜索用时 312 毫秒
471.
472.
通过分析S700K型道岔发生灰显故障的各种原因,提出相应的改进措施。采用冗余技术,解决道岔速动开关和安全开关接点接触不良的问题,消除道岔灰显故障,减少对运营的影响。 相似文献
473.
CAE分析是卡扣结构设计的重要方法。本文通过ABAQUS,分析并优化一类典型天窗开关底座卡扣的拔出力,有效地找出了设计缺陷。运用动力学分析与实测对比,成功地解决了底座卡扣脱出问题。 相似文献
474.
475.
476.
477.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(6):734-755
A model for simulation of dynamic interaction between a railway vehicle and a turnout (switch and crossing, S&C) is validated versus field measurements. In particular, the implementation and accuracy of viscously damped track models with different complexities are assessed. The validation data come from full-scale field measurements of dynamic track stiffness and wheel–rail contact forces in a demonstrator turnout that was installed as part of the INNOTRACK project with funding from the European Union Sixth Framework Programme. Vertical track stiffness at nominal wheel loads, in the frequency range up to 20?Hz, was measured using a rolling stiffness measurement vehicle (RSMV). Vertical and lateral wheel–rail contact forces were measured by an instrumented wheel set mounted in a freight car featuring Y25 bogies. The measurements were performed for traffic in both the through and diverging routes, and in the facing and trailing moves. The full set of test runs was repeated with different types of rail pad to investigate the influence of rail pad stiffness on track stiffness and contact forces. It is concluded that impact loads on the crossing can be reduced by using more resilient rail pads. To allow for vehicle dynamics simulations at low computational cost, the track models are discretised space-variant mass–spring–damper models that are moving with each wheel set of the vehicle model. Acceptable agreement between simulated and measured vertical contact forces at the crossing can be obtained when the standard GENSYS track model is extended with one ballast/subgrade mass under each rail. This model can be tuned to capture the large phase delay in dynamic track stiffness at low frequencies, as measured by the RSMV, while remaining sufficiently resilient at higher frequencies. 相似文献
478.
479.
480.
概述汽车局域互联网络LIN技术的研究现状,并在重型汽车上采用总线方式对开关控制网络进行设计,在此基础上对翘板开关结点、多功能转向盘结点、门窗控制结点等开关控制模块进行设计。采用先进的CANoe仿真软件进行全数字总线仿真。仿真测试结果表明,该系统功能设计正确、合理,所有部件都能正常工作。 相似文献