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91.
基于推广卡尔曼滤波的无源定位系统仿真 总被引:1,自引:0,他引:1
在现代电子战、信息战环境中,由于利用目标辐射电磁信息的无源探测定位系统具有自身隐蔽和探测距离远等优点,因此它具有重要的应用价值,并已成为当今非线性跟踪与估计研究领域的热点问题、针对无源定位中状态空间模型非线性和程度较高所引起的滤波发散问题,分析总结了推广卡尔曼滤波(EKF)次优递推滤波过程,最后给出滤波方程及仿真结果. 相似文献
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为进一步提高机动目标的跟踪精度和估值算法的数值稳定性,文章基于平方根UKF(square root UKF:SR-UKF)和固定延迟平滑算法(fixed-lag smoothing)提出一种新的固定延迟平方根UKS算法(fixed-lag square root unscentedkal man smoothing:FL-SR-UKS)。数值仿真说明该算法可以有效处理机动目标跟踪问题,且状态估值精度优于SR-UKF。 相似文献
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Detection of weak underwater signals is an area of general interest in marine engineering. A weak signal detection scheme
was developed; it combined nonlinear dynamical reconstruction techniques, radial basis function (RBF) neural networks and
an extended Kalman filter (EKF). In this method chaos theory was used to model background noise. Noise was predicted by phase
space reconstruction techniques and RBF neural networks in a synergistic manner. In the absence of a signal, prediction error
stayed low and became relatively large when the input contained a signal. EKF was used to improve the convergence rate of
the RBF neural network. Application of the scheme to different experimental data sets showed that the algorithm can detect
signals hidden in strong noise even when the signal-to-noise ratio (SNR) is less than −40d B. 相似文献
96.
城市道路网络动态OD估计模型 总被引:12,自引:3,他引:9
针对以动态交通管理与控制为目标的动态交通需求计算问题,分析了OD量与交叉口转向交通量的动态关系,将其作为新的系统测量量引入,以此建立了同时考虑路段断面交通量和交叉口转向交通量的状态空间模型,得到了基于城市道路网络的动态OD估计模型,给出了考虑不等式约束的卡尔曼滤波递推方程及相应算法过程。利用微观仿真软件Paramics所建立的实验平台对该模型进行了仿真验证。结果表明:应用该模型进行交通量计算,与传统的仅考虑路段断面交通量模型相比,绝对误差平均减少9%,相对误差平均减少20%,而且其能更好地反映交通量真实值随时间变化的情况,计算结果明显优于传统模型。 相似文献
97.
PANG Yong-jie SUN Yu-shan GAN Yong WAN Lei 《船舶与海洋工程学报》2006,5(4):8-13
GPS/Dead-reckoning navigation system for autonomous underwater vehicle (AUV) is introduced, which includes navigation overall architecture, hardware and software structure. Dead-reckoning theory is presented in details. And the strong tracking Kalman filter and Singer model are applied to handle the imprecise navigation mode, which can improve the navigation system's precision and reliability. Finally, the sea experiments which include autonomous search mission in an unknown area and long distance motion are conducted to demonstrate the reliability and feasibility of the navigation system. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(12):1695-1715
Reliability and dependability in complex mechanical systems can be improved by fault detection and isolation (FDI) methods. These techniques are key elements for maintenance on demand, which could decrease service cost and time significantly. This paper addresses FDI for a railway vehicle: the mechanical model is described as a multibody system, which is excited randomly due to track irregularities. Various parameters, like masses, spring- and damper-characteristics, influence the dynamics of the vehicle. Often, the exact values of the parameters are unknown and might even change over time. Some of these changes are considered critical with respect to the operation of the system and they require immediate maintenance. The aim of this work is to detect faults in the suspension system of the vehicle. A Kalman filter is used in order to estimate the states. To detect and isolate faults the detection error is minimised with multiple Kalman filters. A full-scale train model with nonlinear wheel/rail contact serves as an example for the described techniques. Numerical results for different test cases are presented. The analysis shows that for the given system it is possible not only to detect a failure of the suspension system from the system's dynamic response, but also to distinguish clearly between different possible causes for the changes in the dynamical behaviour. 相似文献
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