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151.
基于GAS的图像跟踪系统及其实现方案 总被引:1,自引:0,他引:1
利用遗传优化算法实现了一个目标跟踪系统,将传统的目标搜索、目标分割、目标定位及跟踪状态评估等过程都由遗传算法来实现,使系统结构简单,易于实现。并分析了利用 TMS32 0 C6x实时实现遗传优化跟踪过程的可能性,最后给出了该系统的实现方案 相似文献
152.
基于Gabor滤波器的图像目标识别方法 总被引:2,自引:0,他引:2
为了给机器人视觉导航提供有效信息,提出一种基于图像匹配的目标识别方法.对CCD采集的目标图像,由 Gabor 变换生成的二维Gabor 滤波器有着优良的滤波器性能,不需要对图像进行分割,能适应一定的旋转、尺度、光照的变化,通过多个频率和角度的Gabor算子与图像的卷积,获取图像全局信息的特征描述.分类方法采用统计学习理论基础上发展起来的一种新的机器学习方法——支持向量机(SVM, Support Vector Machines),它可解决模型选择、过学习、维数灾难等问题.通过支持向量机进行多维特征向量的分类.该方法可达到较高的识别率,达到实时处理的要求,可以在人脸识别、机器人视觉定位等领域得到应用. 相似文献
153.
惯性敏感器与星敏感器之间在轨自主标定比较研究 总被引:2,自引:0,他引:2
惯性敏感器与星敏感器组合定姿是航天器高精度姿态确定的常用手段。通常将惯性敏感器的常值漂移作为扩展状态进行标定,而将星敏感器的常值偏差作为扩展状态进行估计也是可能的。本文对这两种方法的定姿精度进行了分析比较,给出了选用的准则。 相似文献
154.
Pegah Abdollahzadeh Sayyed Majid Esmailifar 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(5):1506-1525
The present study aimed to propose translational and rotational control of a chaser spacecraft in the close vicinity docking phase with a target subjected to external disturbances. For this purpose, two sliding mode controls (SMC) are developed to coordinate the relative position and attitude of two spacecraft. The chaser is guided to the tumbling target by the relative position control, approaching in the direction of the target docking port. At the same moment, the relative attitude control coordinates the chaser attitude so that it can be aligned with the target orientation. These control systems regulate the relative translational and rotational velocities to be zero when two spacecraft are docking. The robustness of the closed-loop system in the presence of external disturbances, measurement noises and uncertainties is guaranteed by analyzing and calculating the control gains via the Lyapunov function. The simulations in different scenarios indicated the effectiveness of the controller scheme and precise maneuver regarding the accuracy of docking conditions. 相似文献
155.
《中国航空学报》2020,33(11):2831-2834
Distributed autonomous situational awareness is one of the most important foundation for Unmanned Aerial Vehicle (UAV) swarm to implement various missions. Considering the application environment being usually characterized by strong confrontation, high dynamics, and deep uncertainty, the distributed situational awareness system based on UAV swarm needs to be driven by the mission requirements, while each node in the network can autonomously avoid collisions and perform detection mission through limited resource sharing as well as complementarity of respective advantages. By efficiently solving the problems of self-avoidance, autonomous flocking and splitting, joint estimation and control, etc., perception data from multi-platform multi-source should be extracted and fused reasonably, to generate refined, tailored target information and provide reliable support for decision-making. 相似文献
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157.
针对参数已知的线性定常二阶系统,本文给出了直接求解Riccati方程的方法,并在此基础上,将方法得到的结果应用到参数未知的线性定常或慢时变系统中,使用估计参数直接求出反馈增益矩阵,提出了一种类二次型最优控制方法,并证明了该闭环慢时变系统的稳定性。 相似文献
158.
《中国航空学报》2020,33(7):2024-2042
Designing a stable and robust flight control system for an Unmanned Aerial Vehicle (UAV) is an arduous task. This paper addresses the trajectory tracking control problem of a Ducted Fan UAV (DFUAV) using offset-free Model Predictive Control (MPC) technique in the presence of various uncertainties and external disturbances. The designed strategy aims to ensure adequate flight robustness and stability while overcoming the effects of time delays, parametric uncertainties, and disturbances. The six degrees of freedom DFUAV model is divided into three flight modes based on its airspeed, namely the hover, transition, and cruise mode. The Dryden wind turbulence is applied to the DFUAV in the linear and angular velocity component. Moreover, different uncertainties such as parametric, time delays in state and input, are introduced in translational and rotational components. From the previous work, the Linear Quadratic Tracker with Integrator (LQTI) is used for comparison to corroborate the performance of the designed controller. Simulations are computed to investigate the control performance for the aforementioned modes and different flight phases including the autonomous flight to validate the performance of the designed strategy. Finally, discussions are provided to demonstrate the effectiveness of the given methodology. 相似文献
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