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   590篇
  免费   3篇
公路运输   36篇
综合类   161篇
水路运输   141篇
铁路运输   31篇
综合运输   224篇
  2024年   1篇
  2023年   3篇
  2022年   5篇
  2021年   9篇
  2020年   19篇
  2019年   11篇
  2018年   18篇
  2017年   27篇
  2016年   40篇
  2015年   48篇
  2014年   32篇
  2013年   66篇
  2012年   31篇
  2011年   44篇
  2010年   54篇
  2009年   39篇
  2008年   47篇
  2007年   26篇
  2006年   20篇
  2005年   17篇
  2004年   7篇
  2003年   6篇
  2002年   3篇
  2001年   8篇
  2000年   2篇
  1999年   3篇
  1998年   1篇
  1997年   3篇
  1995年   2篇
  1986年   1篇
排序方式: 共有593条查询结果,搜索用时 15 毫秒
71.
非线性优化AHP法在公交服务水平评价中应用   总被引:1,自引:0,他引:1  
本文应用非线性优化AHP法确定指标权重系数,改进了传统AHP法的不足之处,针对评价指标的模糊性,建立城市公交服务水平模糊综合评价模型,并通过实例分析和计算,验证了该方法的可行性和实用性。  相似文献   
72.
公交优先成为大城市交通发展的共识,通过采取技术、政策、管理等一系列的优先措施,才能真正做到公交优先.  相似文献   
73.
日本轨道交通与土地的综合开发   总被引:13,自引:0,他引:13  
分析日本国土开发利用、轨道交通建设运营、以及轨道交通与土地综合开发的成功经验。日本是世界上人口密度最大的国家,采取以轨道交通为骨干的公共交通为主导的城市发展策略,由于轨道交通建设经营主体的多元化,铁道主业与其它产业的兼营,特别是轨道交通与土地的综合开发利用,成功的解决了城市交通问题,实现了轨道交通的商业化建设与运营,实现了城市经济、社会、环境、交通的协调发展。  相似文献   
74.
何立居 《航海技术》2007,(B03):36-38
同步定位卫星通信系统是集精确定位与短文字通信于一体.为海上船舶监控管理提供一个平台。为减小海上船舶海损事故的发生,提高船舶监管能力,探讨基于同步定位卫星通信系统的船舶监控管理系统的特点,以对海上船舶进行监控管理、遇险救助等。  相似文献   
75.
The provision of mechanical ventilation in a semi-confined public transport interchange is mandatory in Hong Kong. The authority recommends the general use of low-level-supply and high-level-exhaust airflow schemes that different from the traditional ventilation concept in that low-level emitted vehicle pollutants are best removed at source. Analyses of air quality at typical public transport interchange environments are conducted for the two airflow schemes. The CFD simulations are generalized by studying light and heavy traffic conditions with adjusted ventilation rates to match the change in vehicle emission levels to examine pollutant concentrations at passenger waiting areas and the elevated footbridges. While the conventional high-level-supply and low-level-exhaust scheme could perform better during light traffic loads, the difference diminishes with increased traffic loads during peak hours. On the other hand, the high-level exhaust scheme has an advantage of serving as a smoke extraction system during a fire outbreak.  相似文献   
76.
铁路公安信息系统的开发和对提高铁路公安快速反应能力,保卫铁路运输生产安全具有重要的意义。作者针对铁路公安信息系统的运行环境,信息传送模式以及系统功能和实现方案作了详细的介绍,该系统已于2000年投入使用并达到了预期的设计目标。  相似文献   
77.
78.
A method to identify vortex-induced forces and coefficients from measured strains of a Steel Catenary Riser (SCR) undergoing vessel motion-induced Vortex-induced Vibration (VIV) is proposed. Euler–Bernoulli beam vibration equations with time-varying tension is adopted to describe the out-of-plane VIV responses. Vortex-induced forces are reconstructed via inverse analysis method, and the Forgetting Factor Least Squares (FF-LS) method is employed to identify time-varying vortex-induced force coefficients, including excitation coefficients and added mass coefficients. The method is verified via a finite element analysis procedure in commercial software Orcaflex. The time-varying excitation coefficients and added mass coefficients of an SCR undergoing vessel motion-induced VIV are investigated. Results show that vessel motion-induced VIV is excited at the middle or lower part of the SCR and in the acceleration period of in-plane velocity, where most of the excitation coefficients are positive, while during the deceleration period, the excitation coefficients becomes too small to excite VIVs. Parameter γ [1] has strong correlation with excitation coefficients. In addition, time-varying tensions contribute significantly to the variations of added mass coefficients under the condition that the ratio of dynamic top tension to pretension exceeds the range of 0.7–1.3. Moreover, chaotic behaviors are observed in vortex-induced force coefficients and are more evident with the increase of vessel motion velocity. This behavior may attribute to the randomness existing in in-plane velocity and its coupling with out-of-plane vibrations.  相似文献   
79.
Using photographs, this paper explores the gendered link between transport and the urban environment. It becomes apparent that moving around in urban spaces is an experience which is or can be fundamentally different for women and men. From pictures I conclude that a historical analysis of gender and urban transport ought to be a straightforward task to undertake: women are clearly visible in the visual record of the transport environment. However, a look at the historiography shows that research on gendering the city mostly deals with workplaces, women’s employment, class and race segregation in urban areas, welfare programmes specially designed to helped women, urban housing and marginalisation of women, housewives, healthcare, homeless women and politics. Gender and transport is hardly to be found: how women move and moved through urban space has not received sustained attention. Further, the main body of scholarly texts lacks in historical concern, stemming from such diverse disciplines as sociology, geography, economic and political sciences, women’s studies and planning.  相似文献   
80.
Over the last few decades, many developing countries have experienced car fleet growth, which has contributed to congestion, increased travel times, and deteriorated public transport reliability and punctuality. However, alternatives to urban mobility can be found by creating policies to stimulate sustainable transportation modes with equal opportunities for all citizens. In this paper, measures of social effective speeds are presented to improve sustainable urban mobility policies in developing countries. Data from the 2018 Origin-Destination Survey of the Metropolitan Region of Recife (Brazil) were used to estimate social effective speeds. The results showed that motorized modes had lower effective speed than non-motorized modes. In addition, total external costs were $2 billion USD per year. The social effective speed will be valuable if inserted in sustainable urban mobility policies in developing countries.  相似文献   
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