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91.
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文章设计一种主动悬架控制策略,通过建立四分之一车辆主动悬架系统模型,设计模糊滑模控制策略对主动悬架系统进行控制,并使用Matlab/Simulink软件对所建立的模型进行仿真分析。通过仿真结果验证了所建模型和控制策略的准确性,同时也改善了悬架系统的性能。 相似文献
93.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(12):1929-1950
In this paper, a method for selecting the dynamic characteristics of seat suspension systems is presented. The basic principle of such a method consists in the shaping of nonlinear seat suspension dynamic behaviour for the different requirements defined by machine operators. A combined optimisation procedure has allowed to find the Pareto-optimal system configuration with simultaneous minimisation of conflicted optimisation criteria: the suspended body acceleration and suspension travel. As an example of the proposed method, the seat with a viscous-elastic passive suspension is investigated and its vibro-isolation properties are shaped by the air-spring and shock-absorber force characteristics. 相似文献
94.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):407-423
A grey prediction fuzzy controller (GPFC) was proposed to control an active suspension system and evaluate its control performance. The GPFC employed the grey prediction algorithm to predict the position output error of the sprung mass and the error change as input variables of the traditional fuzzy controller (TFC) in controlling the suspension system to suppress the vibration and the acceleration amplitudes of the sprung mass for improving the ride comfort of the TFC used; however, the TFC or GPFC was employed to control the suspension system, resulting in a large tire deflection so that the road-holding ability in the vehicle becomes worse than with the original passive control strategy. To overcome the problem, this work developed an enhancing grey prediction fuzzy controller (EGPFC) that not only had the original GPFC property but also introduced the tire dynamic effect into the controller design, also using the grey prediction algorithm to predict the next tire deflection error and the error change as input variables of another TFC, to control the suspension system for enhancing the road-holding capability of the vehicle. The EGPFC has better control performances in suppressing the vibration and the acceleration amplitudes of the sprung mass to improve the ride quality and in reducing the tire deflection to enhance the road-holding ability of the vehicle, than both TFC and GPFC, as confirmed by experimental results. 相似文献
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96.
Parameters optimisation of a vehicle suspension system using a particle swarm optimisation algorithm
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):449-474
The purpose of this paper is to determine the lumped suspension parameters that minimise a multi-objective function in a vehicle model under different standard PSD road profiles. This optimisation tries to meet the rms vertical acceleration weighted limits for human sensitivity curves from ISO 2631 [ISO-2631: guide for evaluation of human exposure to whole-body vibration. Europe; 1997] at the driver's seat, the road holding capability and the suspension working space. The vehicle is modelled in the frequency domain using eight degrees of freedom under a random road profile. The particle swarm optimisation and sequential quadratic programming algorithms are used to obtain the suspension optimal parameters in different road profile and vehicle velocity conditions. A sensitivity analysis is performed using the obtained results and, in Class G road profile, the seat damping has the major influence on the minimisation of the multi-objective function. The influence of vehicle parameters in vibration attenuation is analysed and it is concluded that the front suspension stiffness should be less stiff than the rear ones when the driver's seat relative position is located forward the centre of gravity of the car body. Graphs and tables for the behaviour of suspension parameters related to road classes, used algorithms and velocities are presented to illustrate the results. In Class A road profile it was possible to find optimal parameters within the boundaries of the design variables that resulted in acceptable values for the comfort, road holding and suspension working space. 相似文献
97.
针对某6820型后置旅行客车行驶过程中出现的车身摇晃现象,设计人员简要地从悬架系统的配置及布置方式对故障产生原因进行了分析与探讨。 相似文献
98.
文中针对短斜拉索实际抗弯刚度较大的情况,推导了考虑斜拉索抗弯刚度的索导管安装角度计算公式,以方便地计算出拉索在重力作用下的两端倾角变化值,该推导公式表明,两端倾角变化值除了与斜拉索索力、自重集度、索长有关外,还与拉索自身弹性模量、截面特性等因素有关。通过将索导管修正角度计算式应用于阿蓬江特大桥中,比较计算了不同索导管安装角度结果计算的差异。 相似文献
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100.
新建安九铁路鳊鱼洲长江大桥采用两线350 km/h高铁及两线200 km/h客货共线标准建设。南汊航道桥采用主跨672 m双塔钢箱混合梁交叉索斜拉桥,北汊航道桥采用主跨2×140 m独塔竖琴式预应力混凝土梁斜拉桥,鳊鱼洲及北汊非通航孔区采用48 m简支梁桥,跨北岸大堤采用主跨100 m变高连续梁桥,南、北岸引桥除连续梁外均采用32 m、24 m铁路标准梁,基础均采用桩基础。其中南、北汊航道桥采用整幅修建,其余采用分幅修建。桥址区基岩为灰岩,岩溶发育,设计采用了预注浆及抛填片石粘土法或灌注低标号片石混凝土措施进行处理。 相似文献