全文获取类型
收费全文 | 271篇 |
免费 | 0篇 |
专业分类
公路运输 | 177篇 |
综合类 | 9篇 |
水路运输 | 11篇 |
铁路运输 | 3篇 |
综合运输 | 71篇 |
出版年
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 9篇 |
2017年 | 10篇 |
2016年 | 15篇 |
2015年 | 23篇 |
2014年 | 12篇 |
2013年 | 8篇 |
2012年 | 9篇 |
2011年 | 14篇 |
2010年 | 7篇 |
2009年 | 8篇 |
2008年 | 7篇 |
2007年 | 15篇 |
2006年 | 27篇 |
2005年 | 26篇 |
2004年 | 23篇 |
2003年 | 12篇 |
2002年 | 9篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1992年 | 1篇 |
1990年 | 1篇 |
排序方式: 共有271条查询结果,搜索用时 343 毫秒
111.
112.
113.
114.
115.
116.
生命周期评价及其在汽车排放领域的应用 总被引:1,自引:0,他引:1
介绍了生命周期评价(LCA)的定义、评估对象、范围、评价思路、步骤及其体系框架,说明了汽车排放分析中存在的两种循环(燃料循环和车辆循环)。通过分析汽车生命周期排放模型及其在CATCH(Clean A ccessible Transport for Community Health)研究中的一个实际应用案例,进一步阐明了生命周期评价在对各种燃料进行排放分析过程中的实际应用价值,最后介绍了生命周期评价在国外汽车企业中的研究发展情况、实际产品以及应用前景。 相似文献
117.
118.
119.
120.
This study investigates the effect of traffic volume and speed data on the simulation of vehicle emissions and hotspot analysis. Data from a microwave radar and video cameras were first used directly for emission modelling. They were then used as input to a traffic simulation model whereby vehicle drive cycles were extracted to estimate emissions. To reach this objective, hourly traffic data were collected from three periods including morning peak (6–9 am), midday (11–2 pm), and afternoon peak (3–6 pm) on a weekday (June 23, 2016) along a high-volume corridor in Toronto, Canada. Traffic volumes were detected by a single radar and two video cameras operated by the Southern Ontario Centre for Atmospheric Aerosol Research. Traffic volume and composition derived from the radar had lower accuracy than the video camera data and the radar performance varied by lane exhibiting poorer performance in the remote lanes. Radar speeds collected at a single point on the corridor had higher variability than simulated traffic speeds, and average speeds were closer after model calibration. Traffic emissions of nitrogen oxides (NOx) and particulate matter (PM10 and PM2.5) were estimated using radar data as well as using simulated traffic based on various speed aggregation methods. Our results illustrate the range of emission estimates (NOx: 4.0–27.0 g; PM10: 0.3–4.8 g; PM2.5: 0.2–1.3 g) for the corridor. The estimates based on radar speeds were at least three times lower than emissions derived from simulated vehicle trajectories. Finally, the PM10 and PM2.5 near-road concentrations derived from emissions based on simulated speeds were two or three times higher than concentrations based on emissions derived using radar data. Our findings are relevant for project-level emission inventories and PM hot-spot analysis; caution must be exercised when using raw radar data for emission modeling purposes. 相似文献