全文获取类型
收费全文 | 624篇 |
免费 | 3篇 |
专业分类
公路运输 | 285篇 |
综合类 | 24篇 |
水路运输 | 40篇 |
铁路运输 | 107篇 |
综合运输 | 171篇 |
出版年
2022年 | 14篇 |
2021年 | 24篇 |
2020年 | 56篇 |
2019年 | 8篇 |
2018年 | 41篇 |
2017年 | 23篇 |
2016年 | 33篇 |
2015年 | 38篇 |
2014年 | 47篇 |
2013年 | 20篇 |
2012年 | 37篇 |
2011年 | 40篇 |
2010年 | 27篇 |
2009年 | 28篇 |
2008年 | 14篇 |
2007年 | 31篇 |
2006年 | 31篇 |
2005年 | 34篇 |
2004年 | 24篇 |
2003年 | 23篇 |
2002年 | 7篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 4篇 |
排序方式: 共有627条查询结果,搜索用时 500 毫秒
441.
Nathaniel S. Pearre Willett Kempton Randall L. Guensler Vetri V. Elango 《Transportation Research Part C: Emerging Technologies》2011,19(6):1171-1184
One full year of high-resolution driving data from 484 instrumented gasoline vehicles in the US is used to analyze daily driving patterns, and from those infer the range requirements of electric vehicles (EVs). We conservatively assume that EV drivers would not change their current gasoline-fueled driving patterns and that they would charge only once daily, typically at home overnight. Next, the market is segmented into those drivers for whom a limited-range vehicle would meet every day’s range need, and those who could meet their daily range need only if they make adaptations on some days. Adaptations, for example, could mean they have to either recharge during the day, borrow a liquid-fueled vehicle, or save some errands for the subsequent day. From this analysis, with the stated assumptions, we infer the potential market share for limited-range vehicles. For example, we find that 9% of the vehicles in the sample never exceeded 100 miles in one day, and 21% never exceeded 150 miles in one day. These drivers presumably could substitute a limited-range vehicle, like electric vehicles now on the market, for their current gasoline vehicle without any adaptation in their driving at all. For drivers who are willing to make adaptations on 2 days a year, the same 100 mile range EV would meet the needs of 17% of drivers, and if they are willing to adapt every other month (six times a year), it would work for 32% of drivers. Thus, it appears that even modest electric vehicles with today’s limited battery range, if marketed correctly to segments with appropriate driving behavior, comprise a large enough market for substantial vehicle sales. An additional analysis examines driving versus parking by time of day. On the average weekday at 5 pm, only 15% of the vehicles in the sample are on the road; at no time during the year are fewer than 75% of vehicles parked. Also, because the return trip home is widely spread in time, even if all cars plug in and begin charging immediately when they arrive home and park, the increased demand on the electric system is less problematic than prior analyses have suggested. 相似文献
442.
本文主要针对气电混合动力公交车的经济性进行了研究,并通过路谱采集分析燃气发动机实际常用工作区域,结合发动机燃烧特性分析发动机燃气经济性。并通过对电控发动机重新标定达到气耗百公里降低2-3公斤。 相似文献
443.
A choice experiment on alternative fuel vehicle preferences of private car owners in the Netherlands
This paper presents results of an online stated choice experiment on preferences of Dutch private car owners for alternative fuel vehicles (AFVs) and their characteristics. Results show that negative preferences for alternative fuel vehicles are large, especially for the electric and fuel cell car, mostly as a result of their limited driving range and considerable refueling times. Preference for AFVs increases considerably with improvements on driving range, refueling time and fuel availability. Negative AFV preferences remain, however, also with substantial improvements in AFV characteristics; the remaining willingness to accept is on average € 10,000–€ 20,000 per AFV. Results from a mixed logit model show that consumer preferences for AFVs and AFV characteristics are heterogeneous to a large extent, in particular for the electric car, additional detour time and fuel time for the electric and fuel cell car. An interaction model reveals that annual mileage is by far the most important factor that determines heterogeneity in preferences for the electric and fuel cell car. When annual mileage increases, the preference for electric and fuel cell cars decreases substantially, whilst the willingness to pay for driving range increases substantially. Other variables such as using the car for holidays abroad and the daily commute also appear to be relevant for car choice. 相似文献
444.
445.
446.
447.
HC9S12单片机在混合动力汽车ISG控制系统中的应用 总被引:3,自引:2,他引:1
基于MC68HC9S12DP256B单片机,研制了混合动力汽车(HEV)集成化动力总成(ISG)控制系统,提出了软硬件设计、电机和动力电池的模糊控制和动力总成的控制策略。 相似文献
448.
449.
续驶里程试验方法高效、合理,可以用较低的试验成本得到较理想的可信度结果,试验仅需一段1500m的试验道路、几百元一台的GPS测速仪和几只标杆,非常方便电动车企业(特别是还没有装备底盘测功机的企业)自行组织试验,以获得第一手试验数据。 相似文献
450.