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921.
922.
Janusz Gajda Piotr Piwowar Ryszard Sroka Marek Stencel Tadeusz Zeglen 《Transportation Research Part C: Emerging Technologies》2012,21(1):57-66
This article presents the findings of model and field research into narrow inductive loop used as vehicle wheels detector in normal traffic conditions. The efficiency of the solution was compared with that of strip, polymeric piezoelectric detectors. The findings confirmed that narrow inductive loops can be successfully applied as wheel detectors. 相似文献
923.
Leon RaykinMatthew J. Roorda Heather L. MacLean 《Transportation Research Part D: Transport and Environment》2012,17(3):243-250
We evaluate the implications of a range of driving patterns on the tank-to-wheel energy use of plug-in hybrid electric vehicles. The driving patterns, which reflect short distance, low speed, and congested city driving to long distance, high speed, and uncongested highway driving, are estimated using an approach that involves linked traffic assignment and vehicle motion models. We find substantial variation in tank-to-wheel energy use of plug-in hybrid electric vehicles across driving patterns. Tank-to-wheel petroleum energy use on a per kilometer basis is lowest for the city and highest for the highway driving, with the opposite holding for a conventional internal combustion engine vehicle. 相似文献
924.
Samuel Rodman Oprešnik Tine SeljakFran?išek Bizjan Toma? Katrašnik 《Transportation Research Part D: Transport and Environment》2012,17(3):221-227
This paper examines the influence of compressed natural gas, liquefied petroleum gas and gasoline fuel on the exhaust emissions and the fuel consumption of a spark-ignition engine powered passenger car. The vehicle was driven according to the urban driving cycle and extra urban driving cycle speed profiles with the warmed-up engine. Cause and effect based analysis reveals potential for using different fuels to reduce vehicle emission and deficiencies associated with particular fuels. The highest tank to wheel efficiency and the lowest CO2 emission are observed with the natural gas fuelled vehicle, that also featured the highest total hydrocarbon emissions and high NOx emissions because of fast three way catalytic converter aging due the use of the compressed natural gas. Retrofitted liquefied petroleum gas fuel supply systems feature the greatest air-fuel ratio variations that result in the lowest TtW efficiency and in the highest NOx emissions of the liquefied gas fuelled vehicle. 相似文献
925.
通过编组场尾部判辆技术实现编尾调车作业跟踪,对提高编组站综合自动化整体水平具有重要意义。本文建立了模型,讨论利用传感器判断车列辆数和速度的方法。 相似文献
926.
927.
四轮转向车辆多体仿真与试验研究 总被引:1,自引:0,他引:1
以四轮转向原理样车为对象,运用多体动力学理论对四轮转向车辆的转向特性进行了计算机仿真研究和试验验证。对建立整车多体模型的方法进行了论述。通过对仿真数据与样车试验结果的对比分析,证明了四轮转向多体模型各类参数和控制方法的正确性和适用性。最后利用建立的整车多体模型,仿真分析了前后悬架刚度对操纵稳定性的影响,以及制动转向时的转向响应特性。 相似文献
928.
考虑驾驶员系三点式安全带,根据运动学、驾驶舒适性和车辆安全性建立了基于铰链转动极限的4自由度手臂运动学模型,提出了雅克比奇异性的奇异表面的识别方法,并得出了系三点式安伞带驾驶员手伸及界面的解析解,利用可视化技术对驾驶员手伸及界面进行了可视化处理。 相似文献
929.
基于某纯电动车的开发案例,通过对整车性能分类、性能开发关键路径、目标设定及达成管理等方面进行研究。同时为了更好的在整车开发过程中对整车性能进行管控,结合公司实际情况对性能集成的工作进行了明确定义,实践表明该管理策略可执行度高,且能顺利推动性能集成工作开展。研究为后续整车性能在开发中的应用管理提供参考。 相似文献
930.
Lei Xu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(3):444-469
A stochastic mathematical model is developed to evaluate the dynamic behaviours and statistical responses of vehicle–track systems when random system excitations including crosswinds and track irregularities are imposed. In this model, the railway vehicle is regarded as a multi-rigid-body system, the track system is modelled by finite element theory. These two systems are spatially coupled by the nonlinear wheel–rail contact forces and unsteady aerodynamic forces. The high efficiency and accuracy of this stochastic model are validated by comparing to the robust Monte-Carlo method. Numerical studies show that crosswinds have a great influence on the dynamic performance of vehicle–track systems, especially on transverse vibrations. When the railway vehicle initially runs into the wind field, it will experience a severe vibration stage, and then stepping into a relatively steady state where the fluctuating winds and track irregularities will play deterministic roles in the deviations of system responses. Moreover, it is found that track irregularities should be properly considered in the safety assessment of the vehicle even in strong crosswinds. 相似文献