全文获取类型
收费全文 | 1092篇 |
免费 | 74篇 |
专业分类
公路运输 | 244篇 |
综合类 | 312篇 |
水路运输 | 348篇 |
铁路运输 | 139篇 |
综合运输 | 123篇 |
出版年
2024年 | 9篇 |
2023年 | 7篇 |
2022年 | 36篇 |
2021年 | 40篇 |
2020年 | 42篇 |
2019年 | 22篇 |
2018年 | 32篇 |
2017年 | 48篇 |
2016年 | 48篇 |
2015年 | 59篇 |
2014年 | 90篇 |
2013年 | 76篇 |
2012年 | 101篇 |
2011年 | 94篇 |
2010年 | 77篇 |
2009年 | 71篇 |
2008年 | 58篇 |
2007年 | 76篇 |
2006年 | 49篇 |
2005年 | 37篇 |
2004年 | 28篇 |
2003年 | 12篇 |
2002年 | 9篇 |
2001年 | 10篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1985年 | 1篇 |
排序方式: 共有1166条查询结果,搜索用时 15 毫秒
291.
方显华 《筑路机械与施工机械化》2012,29(9):80-82
通过对当前公路机械设备管理中存在的设备效率不高、管理人员素质不高、修理维护成本较高等现状进行分析,引入全员生产维修(TPM)管理理念,并在公路机械设备管理中提出相应的TPM管理模式,对公路部门或施工单位的机械设备管理具有一定的参考价值. 相似文献
292.
293.
294.
This study provide a straightforward way of examining the rebound effects of switching to more fuel efficient technologies, as well as determining the distribution of the effects in the household sector, including both the residential and transport sectors. A SP-off-RP survey conducted in Japan in 2012 asked people to state their preference for the reallocation behaviors after informing them of their annual operating cost saving resulting from the vehicle efficiency improvement. Coupled who save money from relocation are more likely to spend this either on housing features or transport; supporting the idea of rebound effects, although not only limited to within the transport sector. Regarding the distribution of rebound effects, domestic appliances are more likely to be affected than vehicles. 相似文献
295.
Transformation of the motor vehicle fleet has been an important feature of the world’s peak car phenomenon. Very few urban transport studies have explored such important changes in large urban cities. Using an innovative green vehicle datasets constructed for 2009 and 2014, this paper investigates the ongoing change in urban private vehicle fleet efficiency (VFE) in Brisbane. The spatial patterns of VFE change were examined with social-spatial characteristics of the urban area. The results showed that the social and spatial effect of VFE changes remain uneven over urban space. The inner urban areas have experienced higher level of VFE change, whilst people in the outer and oil vulnerable areas showed a low tendency in shifting to more efficient vehicles. The implication of VFE change for future household vehicle adoption was also evaluated based on a cost-benefit analysis of new vehicle technology costs and expected fuel savings for households that choose a fuel efficient vehicle. The results show that imposing a stronger national fuel economy target in the long term would accelerate evolution of vehicle fleets and oil vulnerability reduction in Brisbane. 相似文献
296.
计算对接缝压实耗损、摩阻耗损和收缩徐变耗损,借助工程有限元ANSYS系统对块式、肋式转向块的功效适用性开展模拟计算分析,揭示预应力耗损和两种转向块结构型式对工程技术实现以及施工中的结构安全性影响,对同类桥梁建设提供技术参考. 相似文献
297.
介绍深圳CCT港区惠州QCT港区集装箱码头堆场面层结构,采用土工格栅代替习惯用的碎石垫层和改进后的水泥稳定砂垫层,简化了施工工艺,提高了工程质量,降低了工程成本. 相似文献
298.
分析了汽车制动能量回收再利用的几种典型方式及现状,研究了利用汽车制动能量提高发动机充量系数,从而提高发动机功率的理论依据,并利用GT-POWER软件进行了模拟分析。分析表明,利用制动能量能有效提高发动机的充量系数。 相似文献
299.
300.
Efficiency of urban public transit: A meta analysis 总被引:2,自引:0,他引:2
The aim of this paper is twofold. First, to provide a statistical overview of the literature on public transit efficiency performance. Second, to statistically explain the variation in efficiency findings reported in the literature. To this end, first some key concepts of efficiency analysis will be introduced, while next the different frontier methodologies that are used in the literature will be discussed. The empirical part of this paper consists of a statistical summary of the literature as well as meta-regression analyses for different samples of the literature in order to identify key determinants of technical efficiency (TE) of public transit operators. For a broad sample of observations, we found significant and consistent effects of the type of database, region and output measurement method. For the sample of non-parametric studies we found that the type of frontier assumptions also have an impact on the efficiency ratio. Further results show that there is no statistical difference in TE ratios between parametric and non-parametric studies. Finally, we found a positive univariate relationship between the number of inputs in the estimated specification and the efficiency ratio. 相似文献