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71.
《中国航空学报》2020,33(1):352-364
Unmanned Aerial Vehicle (UAV) swarms have been foreseen to play an important role in military applications in the future, wherein they will be frequently subjected to different disturbances and destructions such as attacks and equipment faults. Therefore, a sophisticated robustness evaluation mechanism is of considerable importance for the reliable functioning of the UAV swarms. However, their complex characteristics and irregular dynamic evolution make them extremely challenging and uncertain to evaluate the robustness of such a system. In this paper, a complex network theory-based robustness evaluation method for a UAV swarming system is proposed. This method takes into account the dynamic evolution of UAV swarms, including dynamic reconfiguration and information correlation. The paper analyzes and models the aforementioned dynamic evolution and establishes a comprehensive robustness metric and two evaluation strategies. The robustness evaluation method and algorithms considering dynamic reconfiguration and information correlation are developed. Finally, the validity of the proposed method is verified by conducting a case study analysis. The results can further provide some guidance and reference for the robust design, mission planning and decision-making of UAV swarms. 相似文献
72.
《中国航空学报》2020,33(11):2989-2998
Unmanned Aerial Vehicles (UAVs) cooperative multi-task system has become the research focus in recent years. However, the existing network frameworks of UAVs are not flexible and efficient enough to deal with the complex multi-task scheduling, because they are not able to perceive the different features. In this paper, a novel cooperated UAVs network framework for multi-task scheduling is proposed. It is a three-layer network including a core layer, an aggregation layer and an execution layer, which enhances the efficiency of multi-task distribution, aggregation and transmission. Furthermore, an AggreGate Flow (AGFlow) based scheduler is dedicatedly designed to maximize the task completion rate, whose key point is to aggregate flows belonging to one task during the multi-task transmission of UAVs network and to allocate priority by calculating the urgency-level of each AGFlow. Simulation results demonstrate that, compared with that of state-of-the-art scheduler, the average task completion rate of AGFlow based scheduler is raised by 0.278. 相似文献
73.
《中国航空学报》2020,33(3):1037-1056
The paper proposes a Virtual Target Guidance (VTG)-based distributed Model Predictive Control (MPC) scheme for formation control of multiple Unmanned Aerial Vehicles (UAVs). First, a framework of distributed MPC scheme is designed in which each UAV only shares the information with its neighbors, and the obtained local Finite-Horizon Optimal Control Problem (FHOCP) can be solved by swarm intelligent optimization algorithm. Then, a VTG approach is developed and integrated into the distributed MPC scheme to achieve trajectory tracking and obstacle avoidance. Further, an event-triggered mechanism is proposed to reduce the computational burden for UAV formation control, which takes into consideration the predictive state errors as well as the convergence of cost function. Numerical simulations show that the proposed VTG-based distributed MPC scheme is more computationally efficient to achieve formation control of multiple UAVs in comparison with the traditional distributed MPC method. 相似文献
74.
姚姣 《中国民航飞行学院学报》2014,25(5):30-32
针对ATC3000空管自动化系统的运行要求以及飞行管制区现场实际工作的需要,介绍了ATC3000航空地图制作软件的关键技术。文中分析了该软件的结构以及在Windows系统中使用Delphi开发的具体实现技术。 相似文献
75.
76.
将准最优控制理论用于轨道自主快速交会时线性二次型调节器的设计。根据轨道交会动力学和基于线性二次型最优控制律的轨道交会优化,提出了一种线性二次型准最优控制器的设计,并证明了系统的稳定性。理论分析和仿真结果表明,该控制律的交会精度较高、计算量小,可实现轨道交会控制的自主性和快速性。 相似文献
77.
近年来,无人车在巡检、探测等方面的应用愈发广泛,且应用环境愈发复杂。在这些应用中,无人车必须对自身的位姿进行准确估计,以确保作业安全、高效完成。其中,可在复杂环境下适用的自主导航能力是核心关键技术。提出了一种基于惯性/里程计/激光雷达的地面无人车导航方法,区别于传统的激光雷达SLAM方法,该方法根据已知的几何结构特征进行定位,避免了因有效点数量稀少而导致的匹配误差。同时对惯性/里程计/激光雷达的融合算法进行了研究,提高了自主导航系统的鲁棒性和准确性。最后,在Gazebo中搭建了相应的仿真环境,并进行了算法验证。仿真结果表明,该方法能够实现无人车在巡检过程中实时可靠的自主导航,具有较好的工程应用价值。 相似文献
78.
介绍了EMR系统 机器人的自主操作方案和硬件组成,在此基础上,详细地讨论了采用启发式搜索算法的行走结点自主规划,以及任务规划和子任务协调,通过仿真和实验表明该方法是成功的。 相似文献
79.
80.
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