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221.
针对高水压作用下大张开量盾构隧道接缝防水密封垫的设计与选型,提出有效接触应力概念。 依托南京和燕路过江隧道工 程,利用大型有限元软件ABAQUS建立完整的沟槽、橡胶止水条带与弹性密封垫的数值模型,对典型错台及张开工况下管片接缝防 水性能进行分析,揭示大张开量条件下管片接缝密封垫错台及张开时的变形与接触应力分布特性。 研究结果表明: 1)密封垫与密 封垫接触面上的扭曲交互能提高接触面上的有效应力占比; 2)圆形孔密封垫错台情况下,密封垫与沟槽之间的有效应力占比要低 于密封垫与密封垫之间的有效应力占比,密封垫与沟槽间的渗水路径在密封垫防水设计时需重点考虑。 相似文献
222.
介绍了国内外接触网可靠性研究的现状,分析了接触网的主要故障、接触网强度可靠性分析的计算模型和可靠性计算方法,对接触网可靠性研究存在的难点及其进一步研究的方向提出了几点建议。 相似文献
223.
224.
根据合宁铁路客运专线隧道结构条件,介绍了目前客运专线隧道内主要采用的几种悬挂方式,从悬挂类型、支持结构、下锚补偿等方面进行了对比,并对不同隧道结构条件下各种悬挂方式的可行性进行了研究分析。 相似文献
225.
广州地铁二号线列车受电弓碳滑板异常磨耗分析 总被引:1,自引:0,他引:1
刘国良 《电力机车与城轨车辆》2008,31(2):52-53
分析了可能造成广州地铁二号线列车受电弓碳滑板出现异常磨耗问题的原因,确定造成碳滑板异常磨耗的因素主要包括:接触网布置的均匀性及受电弓弓头结构、升弓保持力等。 相似文献
226.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(10):1135-1154
This paper presents a model simulating rail roughness growth in which the interaction of a wheelset with the track is considered. The aim is to investigate any possible mechanism for roughness growth due to the coupling between the vertical dynamics, the torsional vibration across the axle of the wheelset and the non-steady contact mechanics. The time-domain simulations are carried out for a driven wheelset on tangent track. Both rigid and flexible are considered with parameter variations for moments of the wheelset, vehicle speeds and wavelengths of initial roughnesses. The 2D non-Hertzian and non-steady contact model used in simulations are based on influence coefficients obtained from a boundary element model. The nonlinear development of the rail roughnesses after millions of wheelset passages is also presented. 相似文献
227.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):341-357
This article deals with the application of the FastSim algorithm to the solution of the tangential contact problem for non-elliptical contact areas. At first, the causes creating problems for the solution of non-hertzian contact areas with this algorithm shall be analyzed. Then, different currently existing methods shall be studied, analyzing their accuracy characteristics and computational cost to determine whether or not they are appropriate to use in dynamic simulations. Finally, a new strategy shall be proposed that, in the opinion of the authors, offers good characteristics of precision and computational cost. 相似文献
228.
229.
This article sets out an optimum synthesis methodology for wheel profiles of railway vehicles in order to secure good dynamic behaviour with different track configurations. Specifically, the optimisation process has been applied to the case of rail wheelsets mounted on double-gauge bogies that move over two different gauges, which also have different types of rail: the Iberian gauge (1668 mm) and the International Union of Railways (UIC) gauge (1435 mm). Optimisation is performed using Genetic Algorithms and traditional optimisation methods in a complementary way. The objective function used is based on an ideal equivalent conicity curve which ensures good stability on straight sections and also proper negotiation of curves. To this end, the curve is constructed in such a way that it is constant with a low value for small lateral wheelset displacements (with regard to stability), and increases as the displacements increase (to facilitate negotiation of curved sections). Using this kind of ideal conicity curve also enables a wheel profile to be secured where the contact points have a larger distribution over the active contact areas, making wear more homogeneous and reducing stresses. The result is a wheel profile with a conicity that is closer to the target conicity for both gauges studied, producing better curve negotiation while maintaining good stability on straight sections of track. The article shows the resultant wheel profile, the contact curves it produces, and a number of dynamic analyses demonstrating better dynamic behaviour of the synthesised wheel on curved sections with respect to the original wheel. 相似文献
230.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1099-1114
In certification of new rail vehicles with respect to running characteristics, a wide variety of operating conditions needs to be considered. However, in associated test runs the wheel–rail friction condition is difficult to handle because the friction coefficient needs to be fairly high and the friction is also generally hard to assess. This is an issue that has been studied in the European project DynoTRAIN and part of the results is presented in this paper. More specifically, an algorithm for estimating the wheel–rail friction coefficient at vehicle certification tests is proposed. Owing to lack of some measurement results, the algorithm here is evaluated in a simulation environment which is also an important step towards practical implementation. A quality measure of the friction estimate is suggested in terms of estimated wheel–rail spin and total creep. It is concluded that, tentatively, the total creep should exceed 0.006 and the spin should be less than 1.0 m?1 for the algorithm to give a good friction estimate. Sensitivity analysis is carried out to imitate measurement errors, but should be expanded in further work. 相似文献