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给出了自行研制的回波模拟器实验样机的原理、性能及其对雷达高度计的测试和定标方法,应用该样机对神舟4号飞船的雷达高度计进行了全系统的地面测试和定标实验。实验结果:有效验证了回波模拟器对雷达高度计的测试和定标方法的可行性,有效验证了神舟4号雷达高度计发射前的动态工作性能。 相似文献
104.
The fault‐tolerant control and vibration suppression for flexible spacecraft without angular velocity measurement are investigated. External disturbances, actuator faults, unknown angular velocity, and flexible vibration are addressed simultaneously. Firstly, a model‐free adaptive supertwisting state observer and an angular velocity calculation algorithm in one step are developed by using attitude information only, which can estimate the angular velocity in finite time. Then, on the basis of angular velocity estimation, a novel continuous multivariable integral sliding mode (CMISM) is proposed for the first time, which is a combination of continuous nominal controller and a modified multivariable twisting controller to reject disturbances and faults. The CMISM can stabilize attitudes in finite time and attenuate chattering effectively. Furthermore, the input shaping technique is developed to achieve effective vibration suppression of the flexible appendages. Finally, the efficiency of the proposed method is illustrated by numerical simulations. 相似文献
105.
空间电磁对接控制问题 总被引:2,自引:1,他引:2
航天器空间电磁对接能避免诸如推进剂消耗、羽流污染和对接冲击等现有基于推力器对接所固有的缺陷,应用前景广阔.空间电磁对接控制目前国内外还没有有效研究,论文主要针对此问题开展初步研究工作.论文首先重点分析空间电磁对接特性及其主要控制问题,然后采用反馈线性化方法对地面二维电磁对接控制模型进行线性化处理、以及基于线性化模型应用Kalman滤波方法估计电磁对接运动状态,最后采用二阶稳定性方法设计控制律并进行仿真分析.理论研究和仿真分析表明:航天器空间电磁对接是可行的,电磁对接非线性模型可以采用反馈线性化方法实现精确线性化,基于线性化模型的二阶稳定性方法满足控制律设计要求. 相似文献
106.
针对大型空间飞行器的大角度姿态控制问题,考虑航天器惯量矩阵中的不确定性和外部扰动力矩,应用高阶滑模控制方法设计了姿态跟踪控制律.采用的二阶滑模控制方法改善了系统针对不确定性及外部扰动的鲁棒性,并减弱了振颤现象.针对所设计的控制器进行了仿真验证,并与一阶滑模控制进行了对比,仿真结果表明了所提出方法的有效性. 相似文献
107.
Robust adaptive attitude control for flexible spacecraft in the presence of SGCMG friction nonlinearity 下载免费PDF全文
This paper investigates attitude maneuver control issues of a flexible spacecraft with pyramid‐type single gimbaled control moment gyroscopes (SGCMGs) as the actuator. The LuGre friction model is adopted to precisely describe the nonlinearity of the SGCMG gimbal friction. Aiming at restraining the adverse effects of the friction existed in SGCMG on the attitude control performance, a robust adaptive attitude controller is proposed, and projection‐based adaptive laws are presented to estimate the friction parametric uncertainties and the bound of friction nonlinearity. By treating the flexible mode coupling effect and external disturbances as lump disturbances, the inertia uncertainties and the bound of the lump disturbances are also estimated and compensated simultaneously to reduce their adverse effect on the system. With the Lyapunov technique, the states of flexible spacecraft control system are proved to be uniformly ultimately bounded. Numerical simulations demonstrate the effectiveness of the proposed scheme. 相似文献
108.
109.
Yoshiro Hamada Takashi OhtaniTakashi Kida Tomoyuki Nagashio 《Control Engineering Practice》2011,19(6):611-625
This paper illustrates a design procedure for a linearly interpolated gain scheduling controller for Engineering Test Satellite VIII (ETS-VIII) using its linear parameter-varying (LPV) model. The LPV model here consists of piecewise-linear functions of the paddle rotation angle and a norm-bounded perturbation. The main purpose of this research is to derive a simple structured scheduling law that can be easily implemented in a satellite onboard computer. The derived gain has only two grid points and is scheduled simply by linear interpolation, which is desirable from the standpoint of implementability. Moreover, since the synthesis condition is based on parameter-dependent Lyapunov functions, it gives less conservative results than existing methods. Simulation results are presented to show the effectiveness of the proposed synthesis. 相似文献
110.
Yonmook Park 《International journal of systems science》2013,44(7):1222-1233
In this paper, a robust and optimal attitude control design that uses the Euler angles and angular velocities feedback is presented for regulation of spacecraft with disturbances. In the control design, it is assumed that the disturbance signal has the information of the system state. In addition, it is assumed that the disturbance signal tries to maximise the same performance index that the control input tries to minimise. After proposing a robust attitude control law that can stabilise the complete attitude motion of spacecraft with disturbances, the optimal attitude control problem of spacecraft is formulated as the optimal game-theoretic problem. Then it is shown that the proposed robust attitude control law is the optimal solution of the optimal game-theoretic problem. The stability of the closed-loop system for the proposed robust and optimal control law is proven by the LaSalle invariance principle. The theoretical results presented in this paper are illustrated by a numerical example. 相似文献