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381.
A reliable estimate of the potential for electrification of personal automobiles in a given region is dependent on detailed understanding of vehicle usage in that region. While broad measures of driving behavior, such as annual miles traveled or the ensemble distribution of daily travel distances are widely available, they cannot be predictors of the range needs or fuel-saving potential that influence an individual purchase decision. Studies that record details of individual vehicle usage over a sufficient time period are available for only a few regions in the US. In this paper we compare statistical characterization of four such studies (three in the US, one in Germany) and find remarkable similarities between them, and that they can be described quite accurately by properly chosen set of distributions. This commonality gives high confidence that ensemble data can be used to predict the spectrum of usage and acceptance of alternative vehicles in general. This generalized representation of vehicle usage may also be a powerful tool in estimating real-world fuel consumption and emissions.  相似文献   
382.
文章针对纯电动汽车用高速电驱动系统的发展现状进行了分析,总结了电驱动系统中的高速永磁同步电动机、电机与减速器的集成化设计、电池的续航能力和安全性能,论述了高速永磁同步电动机的定转子结构与散热系统设计的关键技术,最后展望了纯电动汽车驱动系统发展趋势。  相似文献   
383.
Electrification of the transport sector is considered as a solution to reduce greenhouse gases (GHGs) emissions and achieve sustainable mobility. Specifically in the case of electrification of passenger vehicles, various industrial and policy initiatives have been introduced. In this article, we present and assess three approaches – pro-technology, pro-simplicity and mix (of the aforementioned approaches) – to achieve target emission reductions in the Norwegian road transport sector. We also assess the influence of including ‘Guarantee of Origin’ certification for the electricity production in accounting for typical consumption electricity mix in Norway.Results show that for the same reductions in tail-pipe GHG emissions, pro-technology, pro-simplicity, and the mix scenario offer 22%, 29% and 28% reduction in the life cycle GHG emissions respectively, compared to the reference scenario in year 2020. However, the pro-simplicity scenario requires 25% reduction in vehicle-km driven compared to the pro-technology scenario, which provides the same passenger car mobility as in the reference case. When the GHG intensity of the electricity mix used to power EVs is corrected to account for actual consumption mix in Norway, a 13% reduction in the net GHG benefit of pro-technology scenario is observed.  相似文献   
384.
以某微型汽车为例,建立了其真空助力制动系统的数学模型,对燃油汽车改装为电动汽车后的制动系统真空助力匹配进行了计算分析,从而为电动汽车真空助力系统中真空罐、真空助力器、真空泵的选型和匹配提供了理论依据.通过试验验证可知,本文的真空罐及真空泵阀值选择合理,电动真空泵工作时间为4~6 s.  相似文献   
385.
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   
386.
高健 《天津汽车》2012,(3):17-19
节能与环保已经成为汽车技术发展的2大主题。文章通过对丰田混合动力轿车的系统构成和工作原理的叙述,以及对于混合动力汽车发展现状及趋势的分析,说明了混合动力电动汽车在节能减排方面效果显著,克服了普通电动汽车行驶里程短及充放电技术落后等缺点。表明混合动力电动汽车将成为未来汽车产品的发展方向。  相似文献   
387.
We propose an optimization model based on vehicle travel patterns to capture public charging demand and select the locations of public charging stations to maximize the amount of vehicle-miles-traveled (VMT) being electrified. The formulated model is applied to Beijing, China as a case study using vehicle trajectory data of 11,880 taxis over a period of three weeks. The mathematical problem is formulated in GAMS modeling environment and Cplex optimizer is used to find the optimal solutions. Formulating mathematical model properly, input data transformation, and Cplex option adjustment are considered for accommodating large-scale data. We show that, compared to the 40 existing public charging stations, the 40 optimal ones selected by the model can increase electrified fleet VMT by 59% and 88% for slow and fast charging, respectively. Charging demand for the taxi fleet concentrates in the inner city. When the total number of charging stations increase, the locations of the optimal stations expand outward from the inner city. While more charging stations increase the electrified fleet VMT, the marginal gain diminishes quickly regardless of charging speed.  相似文献   
388.
The transition to low-carbon transportation fuels plays a key role in ongoing efforts to combat climate change. This analysis seeks to optimize potential alternative fuel portfolios that would lead to a 10% reduction in fuel carbon intensity by 2020 as required under California’s Low Carbon Fuel Standard (LCFS).We present a novel, probabilistic modeling approach for evaluating alternative fuel portfolios based on their marginal greenhouse gas (GHG) abatement costs. Applied to a case study region in Northwest California, our model enables us to quantify the financial cost of GHG reduction via each fuel pathway, as well as for a portfolio deployed to meet the LCFS target. It also enables us to explore the sensitivity of the alternative fuel portfolio, evaluating the impact of fluctuating prices, fuel carbon intensities, and technology penetrations on the makeup of the portfolio and on the average cost of GHG abatement.We find that battery electric vehicles play a critical role, as they offer the lowest-financial-cost significant abatement in almost all plausible scenarios. However, electric vehicles alone will not be sufficient to reach the target; low-carbon biofuels can be expected to play a role in the achievement of 2020 Low Carbon Fuel Standard targets.  相似文献   
389.
Battery Electric vehicles (BEVs) are generally considered as potentially contributing to the reduction of CO2 emissions. Consequently, many countries have promoted (or are in the process of promoting) policies aimed at directly or indirectly subsidizing BEVs to accelerate their market uptake. The aim of this paper is to assess whether BEVs’ subsidies are justified (and by what amount) with reference to the carbon component, distinguishing by car segments and countries. To address these research questions, a simulation model is developed, based on the most recent and reliable data available. The model estimates and monetizes the Well-to-Wheel CO2 emissions of six car segments in 28 European countries. The monetary value of the difference of the CO2 emissions between the non-BEVs and the BEVs ranges from −€1133 (tax) to +€3192 (subsidy), depending on the car segment and on the nation considered. These results are then compared to the policies about alternative fuels adopted by the single EU countries, suggesting in some cases the necessity to rethink such incentives.  相似文献   
390.
Fuelled by a rapidly rising human global population, an increasing demand for freedom to travel and the affordability made possible by modern manufacturing there has been an exponential rise in the number of automobiles – in the year 2013 there were in excess of a billion automobiles in use! Three factors that are of serious concern are the consequential energetic, environmental and economic impacts. One solution that is being seen by a number of national governments is the advent (or rather re-introduction) of electric vehicles (EVs). However, one of the key factors that will need to be explored will be the source of the required electricity for the EVs that will define the level of their sustainability.In this article an experimental evaluation of an electric vehicle has been undertaken. The Renault Zoe e-car has been used for this task with the ‘car chasing’ technique employed to measure the driving cycle. The speed and energy use were recorded for the vehicle that was driven along the principal arteries of the City of Edinburgh, Scotland. In a separate activity vehicle driving tests were also undertaken in one town in Slovenia (Celje). In both places urban and suburban routes were covered for different times of the day. Results are presented to quantify the energetic, environmental and economic performance indices for the driven vehicle. A discussion is also provided on the potential for reduction of carbon emissions from the transport sector by provision of environmentally-friendly means of generating electricity.  相似文献   
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