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451.
电动汽车示范运行无线远程监控管理系统的开发研究   总被引:5,自引:0,他引:5  
谢辉  肖斌  郝明德  周能辉 《汽车工程》2006,28(8):734-737,770
电动汽车示范运行服务中心远程监控管理系统基于GPRS网络和Internet网,通过具有CAN接口和GPRS接口的车载智能信息单元,采用无线远程数据传送方式,实现对多辆电动汽车的监控、标定和定位,由此实现故障分析与处理、在线标定与优化、数据记录与分析、电子地图跟踪等功能。为示范运行提供了有效、方便、快捷而且又经济的管理手段。  相似文献   
452.
电动车热泵空调系统的设计分析   总被引:5,自引:0,他引:5  
谢卓  陈江平  陈芝久 《汽车工程》2006,28(8):763-765
对比分析电动车热泵空调系统同燃油汽车空调系统的区别,比较采用不同制冷剂和压缩机电动车热泵空调系统,提出开发适合我国国情的高效节能电动车热泵空调的设计方法。  相似文献   
453.
电动汽车绝缘电阻在线监测方法   总被引:2,自引:0,他引:2  
李景新  樊彦强  姜久春  陈弘 《汽车工程》2006,28(10):884-887
提出通过测量电动汽车直流系统正负母线对电底盘的电压来实时监测绝缘状况的方法。对影响测量精度的主要因素进行相应分析,并提出了提高精度的措施。设计了在线监测系统,并进行了实际装车试验。试验结果表明系统符合预期的设计精度要求,对故障情况可以及时报警,能够较好地完成实时监测电动汽车绝缘性能的任务。  相似文献   
454.
In this paper we discuss the effectiveness, efficiency and feasibility of policy measures that cities may adopt to stimulate the uptake and use of electric vehicles. Our analysis is based on an expert workshop in which municipal policy-makers used a group decision room system to exchange their experiences with electric vehicle related policies. We distinguish six categories of measures: supporting citizens and businesses, supporting charging-infrastructure build up, regulatory measures, raising awareness, government as lead user, and governing the transition with other levels of government. We find two feasible policy mixes of effective and efficient measures, one for cities that strive to be among the global frontrunners and one of no-regret policies that any city should adopt, if it wants to stimulate electric mobility.  相似文献   
455.
Annual expenditures for transportation infrastructure have recently surpassed the funding available through tax and fee collection. One large source of revenue generation for transportation infrastructure is use fees that are charged through taxes on gasoline both on a federal and state level. A massive adoption of electric vehicles (EVs) in the United States would result in significantly lower gasoline consumption and thus reduce the revenue collected to maintain the U.S. transportation infrastructure. We investigate how different vehicles will change the annual fee collected on a marginal basis. In addition, we assess the effects of adoption of alternative vehicles on revenues using several projections of alternative vehicles adoption, both on a state-by-state basis and at the national level. We find that baseline midsize and compact vehicles such as the Toyota Camry and Honda Civic generate approximately $2500–$4000 in tax revenue over their lifetime. Under the current funding structure, battery-electric vehicles (BEVs) such as the Nissan Leaf generate substantially less at $400–$1300, while plug-in hybrid electric vehicles (PHEVs) such as the Chevrolet Volt generate $1500–$2700. Even in states with high lifetime fees due to fuel taxes, such as California, revenue generation can be upwards of 50% lower than in states with high registration fees such as Colorado. Total annual revenue generation decreases by about $200 million by 2025 as a result of EV adoption in our base case, but in projections with larger adoption of alternative vehicles could lead to revenue generation reductions as large as $900 million by 2025. Potential schemes that charge user fees on alternative fuel vehicles to overcome the decrease in revenue include a flat annual registration fee at 0.6% of the vehicle’s manufacturer suggested retail price (MSRP) or 2
per mile fee.  相似文献   
456.
In spite of the purported positive environmental consequences of electrifying the light duty vehicle fleet, the number of electric vehicles (EVs) in use is still insignificant. One reason for the modest adoption figures is that the mass acceptance of EVs to a large extent is reliant on consumers’ perception of EVs. This paper presents a comprehensive overview of the drivers for and barriers against consumer adoption of plug-in EVs, as well as an overview of the theoretical perspectives that have been utilized for understanding consumer intentions and adoption behavior towards EVs. In addition, we identify gaps and limitations in existing research and suggest areas in which future research would be able to contribute.  相似文献   
457.
This study models and examines the taxi customers' preferences for hailing vacant taxis on streets. A stated preference survey was conducted to randomly select and interview 1242 taxi customers at taxi stands and pedestrians on streets, who had experiences of taking taxis recently, about their choices under different given hypothetical scenarios. In total, 4968 observations were collected and used for developing the discrete choice models for the analysis. To account for the potential correlations among alternatives, two nested logit models are developed, calibrated, and compared with a standard multinomial logit model in the investigation. The results of likelihood ratio test demonstrate that one of the developed nested logit models is better than the standard multinomial logit model to describe the search behavior of taxi customers. The model results also show that the walking time to and the waiting time at the location for hailing taxis, the extra travel time to the destination because of local circulation for finding a way from the pickup location heading to a passenger's destination, as well as the taxi customers' perceptions for walking to and waiting at taxi stands were found as significant factors to influence their decisions. In addition, the results of market segmentation analysis illustrate the variations in taxi‐search strategies of taxi customers in different districts and regions. Some policy implications on introducing more taxi stands and improving the utilization rates of taxi stands are also discussed. We believe that the proposed models, findings, and discussion are useful for developing micro‐simulation models to evaluate the performance of road traffic networks with taxi services and developing simulation‐based optimization models to answer policy questions related to taxi services. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
458.
This study aims at investigating the impact and feasibility of charging taxis with toll fee in the pricing zone when designing congestion pricing scheme. A bi‐level programming model is developed to compare the maximum social welfares before and after the congestion charge is imposed on taxis. The lower level is a combined network equilibrium model formulated as a variational inequality program, which considers the logit‐based mode split, route choice, elastic demand, and vacant taxi distributions. The upper level is to maximize the social welfare when toll rates vary. The bi‐level problem can be solved by the genetic algorithm, whereas the lower level is solved by the block Gauss–Seidel decomposition approach together with the method of successive averages and diagonalization algorithm. An application with numerical examples is conducted to demonstrate the effectiveness of the proposed model and algorithm and to reveal some interesting findings. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
459.
本论文介绍了一种基于单片机的电动栏杆机控制系统。此控制系统以单片机为控制电路的核心,采用霍尔传感器检测栏杆机的角度位置,并利用脉冲调制法驱动直流力矩电机。  相似文献   
460.
介绍了石家庄供电段管内京广线电力远动系统的运行状况,阐述了在运行中出现的问题,并分析了原因,进一步探讨了在既有运行设备上进行改造的措施方案和实施后的效果.  相似文献   
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