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201.
文章旨在通过分析纯电动乘用车与传统内燃机汽车在动力系统方面的差别,在以经验公式进行计算的基础上,根据前者动力系统的特点,结合某一款纯电动乘用车的项目,初步提出了纯电动汽车动力系统匹配的基本要求;通过分析现有驱动电机的特点,基于动力性、经济性、续航能力及噪声等因素的考虑,找到了一种能满足现阶段电动车开发的电机种类和参数的选配标准。 相似文献
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城轨交通信号系统的各设备负载都由电源屏和UPS统一供电,而能达到各负载分路供电的电气元件则是通过空气断路器完成.在信号系统的维护过程中,空气断路器选择不当,可能带来很多麻烦.因此,从断路器的种类、功能、应用等几方面,详细介绍了断路器选用时的注意事项. 相似文献
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轮边驱动系统对车辆垂向性能影响的研究现状 总被引:8,自引:0,他引:8
由于引入轮毂电机,使得轮边驱动电动汽车驱动系统的质量显著增加,引起整车非簧载质量相对过大,恶化了车辆垂向性能。在查阅国内外大量文献的基础上,详细介绍了对轮边驱动系统相关问题的研究现状,具体分析了非簧载质量过大对车辆垂向性能的影响以及国内外解决该问题的主要方法和效果,最后对轮边驱动系统未来发展趋势进行了展望。 相似文献
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Strong efforts are spent in automotive engineering for the creation of so called Driving Cycles (DCs). Vehicle DC development has been a topic under research over the last thirty years, since it is a key activity both from an authority and from an industrial research point of view. Considering the innovative characteristics of Electric Vehicles (EVs) and their diffusion on certain contexts (e.g. city centers), the demand for tailored cycles arises. A proposal for driving data analysis and synthesis has been developed through the review and the selection of known literature experiences, having as a goal the application on a EVs focused case study. The measurement campaign has been conducted in the city of Florence, which includes limited traffic areas accessible to EVs. A fleet of EVs has been monitored through a non-invasive data logging system. After data acquisition, time-speed data series have been processed for filtering and grouping. The main product of the activity is a set of DCs obtained by pseudo-randomized selection of original data. The similarity of synthetic DCs to acquired data has been verified through the validation of cycle parameters. Finally, the new DCs and a selection of existing ones are compared on the basis of relevant kinematic parameters and expected energy consumption. The method followed for the creation of DCs has been implemented in a software package. It can be used to generate cycles and, under certain boundary conditions, to get a filtered access to the measured data and provide integration within simulation environment. 相似文献
208.
This study investigates the energy consumption impact of route selection on battery electric vehicles (BEVs) using empirical second-by-second Global Positioning System (GPS) commute data and traffic micro-simulation data. Drivers typically choose routes that reduce travel time and therefore travel cost. However, BEVs’ limited driving range makes energy efficient route selection of particular concern to BEV drivers. In addition, BEVs’ regenerative braking systems allow for the recovery of energy while braking, which is affected by route choices. State-of-the-art BEV energy consumption models consider a simplified constant regenerative braking energy efficiency or average speed dependent regenerative braking factors. To overcome these limitations, this study adopted a microscopic BEV energy consumption model, which captures the effect of transient behavior on BEV energy consumption and recovery while braking in a congested network. The study found that BEVs and conventional internal combustion engine vehicles (ICEVs) had different fuel/energy-optimized traffic assignments, suggesting that different routings be recommended for electric vehicles. For the specific case study, simulation results indicate that a faster route could actually increase BEV energy consumption, and that significant energy savings were observed when BEVs utilized a longer travel time route because energy is regenerated. Finally, the study found that regenerated energy was greatly affected by facility types and congestion levels and also BEVs’ energy efficiency could be significantly influenced by regenerated energy. 相似文献
209.
This paper evaluates the impacts on energy consumption and carbon dioxide (CO2) emissions from the introduction of electric vehicles into a smart grid, as a case study. The AVL Cruise software was used to simulate two vehicles, one electric and the other engine-powered, both operating under the New European Driving Cycle (NEDC), in order to calculate carbon dioxide (CO2) emissions, fuel consumption and energy efficiency. Available carbon dioxide data from electric power generation in Brazil were used for comparison with the simulated results. In addition, scenarios of gradual introduction of electric vehicles in a taxi fleet operating with a smart grid system in Sete Lagoas city, MG, Brazil, were made to evaluate their impacts. The results demonstrate that CO2 emissions from the electric vehicle fleet can be from 10 to 26 times lower than that of the engine-powered vehicle fleet. In addition, the scenarios indicate that even with high factors of CO2 emissions from energy generation, significant reductions of annual emissions are obtained with the introduction of electric vehicles in the fleet. 相似文献
210.
为了分析电池散热问题,文章采用有限元仿真的方法,对串行和并行两种散热方式进行对比方针研究。首先分析了锂电池产热原因,对其产热特性进行了研究。然后针对某款锂离子电池,使用有限元仿真软件Fluent,对串行和并行的两种风冷散热模式进行模拟仿真研究。结果表明:串行通风散热时电池散热比较均匀,靠近进出风口的电池散热效果较好;并行通风散热时散热效果逐渐递增,越靠近出风口的电池散热效果越好。 相似文献