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Robust H∞ controller design for attitude stabilization of flexible spacecraft with input constraints
Chuang Liu Keke Shi Zhaowei Sun 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(5):1498-1522
This paper addresses the attitude stabilization and vibration suppression problem for flexible spacecraft subject to model parameter uncertainty, controller perturbations, external disturbances and input constraints. The attitude model of flexible spacecraft is described and converted into a state space form in terms of passive and active vibration suppression schemes. A novel state feedback controller is proposed based on the exactly available expectation of a new variable, which is introduced to model a randomly occurring controller gain perturbation. Based on Lyapunov stability theory, sufficient conditions for the existence of the nonfragile H∞ controller considering input constraints are given based on linear matrix inequalities (LMIs) in terms of additive perturbation and multiplicative perturbation. Then, the developed controller subject to required constraints can be obtained, where the nonfragile property is fully considered to improve the tolerance to uncertainties in the controller. Numerical simulations are performed to demonstrate the effectiveness and superiority of the proposed control strategy in attitude stabilization and vibration suppression, where it should be noted that the passive vibration suppression scheme is superior for high natural frequencies while the active vibration suppression scheme is superior for low natural frequencies. Moreover, the low natural frequencies have more influence on the performance of attitude stabilization and vibration suppression. 相似文献
184.
考虑末制导阶段捷联导引头视场角限制及攻击角度约束,提出一种基于三维比例导引攻击角度控制的导引律。首先,利用三维矢量制导模型和四元数理论实现三维比例导引的攻击角度预测,进而基于空间几何原理设计一种能够满足视场角约束的三维比例导引攻击角度控制方法。对闭环制导动力学进行分析,并采用李雅普诺夫原理证明视场角受限情况下的制导误差收敛性。分析该制导方法在导弹速度大小变化情况下的轨迹不变性,进而保证制导方法在速度大小变化情况下的有效性。理论分析和仿真校验结果说明了该方法的正确性和有效性。提出的方法可为视场角受限下的攻击角度控制导引律设计提供参考。 相似文献
185.
An experimental investigation on ignition characteristics with air-throttling in an ethylene-fueled scramjet under flight Ma 6.5 conditions was conducted.The dynamic process of air-throttling ignition was explored systematically.The influences of throttling parameters,i.e.,throttling mass rate and duration,were investigated.When the throttling mass rate was 45% of the inflow mass rate,ambient ethylene could be ignited reliably.The delay time from ignition to throttling was about 45–55 ms.There was a threshold of throttling duration under a certain throttling mass rate.It was shorter than 100 ms when the throttling mass rate was 45%.While a 45%throttling mass rate would make the shock train propagate upstream to the isolator entry in about10–15 ms,four lower throttling mass rates were tested,including 30%,25%,20%,and 10%.All of these throttling mass rates could ignite ethylene.However,combustion performances varied with them.A higher throttling mass rate made more ethylene combust and produced higher wall pressure.Through these experiments,some aspects of the relationships between ignition,flame stabilization,combustion efficiency,and air-throttling parameters were brought to light.These results could also be a benchmark for CFD validation. 相似文献
186.
针对再入飞行过程中飞行器末制导启动后制导系统存在的模型不确定性因素以及气动环境复杂等鲁棒制导问题,结合落点角约束条件,提出一种基于二阶滑模的鲁棒末制导律设计方法。基于二阶滑模控制的思想,设计有限时间收敛的二阶滑模末制导律;为了消除有界的内外扰影响同时削弱抖振效果,引入超螺旋算法设计有限时间收敛的连续二阶滑模末制导律。飞行器在该末制导律导引下,弹目视线角速率及落角约束快速收敛,从而保证飞行器有很高的命中精度。基于Lyapunov定理的稳定性理论证明及仿真结果均表明了该末制导方案的有效性。 相似文献
187.
本文针对柔性航天器在惯性参数未知、外界干扰、输入饱和等复杂条件下的姿态控制问题,提出了1种基于神经网络干扰观测器的柔性航天器姿态稳定控制方法。首先,基于包含压电振动抑制输入的柔性航天器姿态动力学模型,构建了包含外界干扰、惯性参数不确定性的综合扰动项;其次,基于RBF神经网络设计干扰观测器与自适应参数调节律实时地估计综合扰动;再次,设计了1种固定时间收敛且有限时间稳定的非线性滑模控制器,并通过Lyapunov理论进行了稳定性分析;最后,利用航天器闭环姿态动力学系统进行数值仿真。结果表明:所设计的基于神经网络干扰观测器的控制方法可以有效实现航天器的姿态稳定、振动抑制与干扰估计,从而顺利完成航天器的高精高稳控制任务。 相似文献
188.
开发教学管理网络系统实现现代化教学管理 总被引:2,自引:0,他引:2
该教学管理网络系统根据教学管理内容和科学、规范、高效等现代化管理要求进行研发,采用信息技术使教学管理达到高效、快速、安全、可靠、开放、共享、交互、协调等现代化管理要求;系统由先进的开发工具进行开发。体系结构采用客户机/服务器(C/S)和浏览器/服务器(B/S)相结合的三层体系结构。 相似文献
189.
Target Feedback Loop / Loop Transfer Recovery (TFL/LTR) synthesis and multiobjective optimization are combined to design robust and well performing controllers in a most general sense. A TFL/LTR synthesis based on quadratic stabilization is used to efficiently synthesize robustly stabilizing controllers. Multiobjective optimization is used to tune synthesis parameters for which the TFL/LTR controller yields good performance in addition to robust stability. The technique is demonstrated in the design of a lateral controller for a high performance aircraft in high incidence regime. 相似文献
190.