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971.
轮速传感器测量汽车轮速信号,用于制动、发动机及变速箱等众多系统控制,是汽车最关键的部件之一。新车型开发阶段,为了对汽车制动防抱死系统(ABS)及早有效的开发验证,需要对轮速传感器进行仿真模拟。文章针对最常用的主动式轮速传感器进行测试与分析,通过设计信号调理电路,成功搭建了ABS硬件在环仿真平台,既简化了汽车开发阶段的验证与测试,又节省了开发成本。 相似文献
972.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):1349-1372
The present analysis is addressed to some promising connection arrangements between the towing vehicles and the towed trailers, where the two units are linked by four-bar isosceles trapeziums in place of the conventional pintle hitch. Two types of instability, of the divergent type or the oscillating type, may be analysed by the Routh–Hurwitz criterion or by the direct analysis of the characteristic equation. The constant term of this equation vanishes at the divergent instability threshold (zero of a real root), whereas the equation splits into two lower degree algebraic ‘sub-equations’ when the oscillating instability arises (pair of pure imaginary roots). A large field of geometrical configurations of the four-bar linkage may be quickly tested by numerical search procedures, including those where the sidebars of the linkage converge towards the inside of the drawing car and shift the relative centre of rotation forward, and those converging backward towards the trailer. Maps of the critical velocity as a function of the geometrical or physical parameters may be easily traced. They clearly show the favourable influence of the forward four-bar connection in general and the benefits achievable comparing with the conventional coupling. Actually, it is conceivable to increase the critical speed by optimising the four-bar design depending on the weight distribution on the axles and on the other geometrical and physical properties. Moreover, this type of connection may produce significant corrections to the under-steering or over-steering conduct of the articulated vehicle. The off-tracking and the manoeuvrability along curved paths are also studied, showing the benefits or the drawbacks of the four-bar linkage for the various configurations. 相似文献
973.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(12):1811-1829
The compensatory (feedback) component of a human driver's steering control is examined. In particular, the effect of the cognitive process is studied. Model predictive control theory is used to implement models of intermittency in cognitive processing. Experiments using a fixed-base driving simulator with periodic occlusion of the visual display are used to reveal the nature of the driver's steering behaviour. An intermittent serial-ballistic control strategy is found to match the measured behaviour better than intermittent zero-order hold or continuous control. The findings may enable some insight to driver-vehicle interaction and vehicle handling qualities. 相似文献
974.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(10):1545-1571
ABSTRACTMulti-trailer articulated heavy vehicles (MTAHVs) are increasingly used around the world due to their economic and environmental benefits. However, MTAHVs exhibit poor maneuverability and low lateral stability, which may lead to fatal traffic accidents. Given the safety risks, it is necessary to solve the steering and stability problems of MTAHVs before they are safely mass deployed on our roads. To this end, active trailer steering (ATS) based on the linear quadratic regulator (LQR) technique has been explored. The LQR-based ATS demonstrates improved maneuverability and enhanced lateral stability. In the ATS design, the vehicle and operating parameters are assumed constant. Thus, it is natural to question the robustness of the ATS in presence of vehicle and operating parameter uncertainties. To address the problem, this paper proposes a robust ATS system. The robust ATS controller is designed using a linear matrix inequality (LMI) based LQR method. In the design, both vehicle and steering actuator parameter uncertainties are considered; to enhance the robustness of the ATS, the weighting matrices of the proposed controller are optimized. The robust controller is applied to an A-Train Double, one type of MTAHV. The effectiveness of the robust ATS is demonstrated using numerical and hardware-in-the-loop real-time simulations. 相似文献
975.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(11):991-1011
A robust nonparametric approach to vehicle stability control by means of a four-wheel steer by wire system is introduced. Both yaw rate and sideslip angle feedbacks are used in order to effectively take into account safety as well as handling performances. Reference courses for yaw rate and sideslip angle are computed on the basis of the vehicle speed and the handwheel angle imposed by the driver. An output multiplicative model set is used to describe the uncertainty arising from a wide range of vehicle operating situations. The effects of saturation of the control variables (i.e. front and rear steering angles) are taken into account by adopting enhanced internal model control methodologies in the design of the feedback controller. Actuator dynamics are considered in the controller design. Improvements on understeer characteristics, stability in demanding conditions such as turning on low friction surfaces, damping properties in impulsive manoeuvres, and improved handling in closed loop (i.e. with driver feedback) manoeuvres are shown through extensive simulation results performed on an accurate 14 degrees of freedom nonlinear model, which proved to give good modelling results as compared with collected experimental data. 相似文献
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