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301.
Positioning error compensation of an industrial robot using neural networks and experimental study 总被引:1,自引:1,他引:0
Due to the characteristics of high efficiency, wide working range, and high flexibility,industrial robots are being increasingly used in the industries of automotive, machining, electrical and electronic, rubber and plastics, aerospace, food, etc. Whereas the low positioning accuracy,resulted from the serial configuration of industrial robots, has limited their further developments and applications in the field of high requirements for machining accuracy, e.g., aircraft assembly.In this paper, a... 相似文献
302.
比较全面地介绍了-宽带中频相位计的研制过程。论述了相位计的工作原理,给出了系统框图。对各个部件的设计做了介绍,并给出了相位计所达到的技术指标。还介绍了系统测试方法和检定方法,对系统的误差做了分析,并给出了理论计算误差与实测误差的对应关系,提出了今后的进一步设想。 相似文献
303.
IPSec VPN为网络创建安全连接的虚拟私网提供了灵活的实现手段,使用户可以避免租用昂贵的专线而采用公网就可以实现广泛的电子商务活动;在IPSec隧道通信协议实现VPN的基础上,详细研究了VPN双极性信号误码率的传输控制,得出了提高带宽B比增加信噪比S/N更有效的结论,并讨论了数字密钥在提高通信系统安全的应用前景。 相似文献
304.
Navigation message designing with high accuracy guarantee is the key to efficient navigation message distribution in the global navigation satellite system(GNSS). Developing high accuracy-aware navigation message designing algorithms is an important topic. This paper investigates the high-accuracy navigation message designing problem with the message structure unchanged.The contributions made in this paper include a heuristic that employs the concept of the estimated range deviation(ERD) to improve the existing well-known navigation message on L1 frequency(NAV) of global positioning system(GPS) for good accuracy service; a numerical analysis approximation method(NAAM) to evaluate the range error due to truncation(RET) of different navigation messages; and a basic positioning parameters designing algorithm in the limited space allocation. Based on the predicted ultra-rapid data from the ultra-rapid data from the international GPS service for geodynamic(IGU), ERDs are generated in real time for error correction.Simulations show that the algorithms developed in this paper are general and flexible, and thus are applicable to NAV improvement and other navigation message designs. 相似文献
305.
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307.
P. Alexander A. de la Torre 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Balloons lead to the highest vertical resolution of air velocity data actually attainable from atmospheric soundings. However, the pendulum-like motion of the balloon-gondola system may significantly affect these measurements if the distance between balloon and gondola is large. This may prevent the study of the highest vertical resolution range obtained. Also, if not appropriately discriminated, these fluctuations could be confused with small scale or turbulent oscillations of the atmosphere. It is shown from simple energy considerations that horizontal and vertical wind velocity perturbations introduced in the observations by the pendulum motion may usually be comparable to typical measurements. Vertical velocity data that were obtained with an instrumented gondola in a zero pressure balloon, which typically reach the lower stratosphere, are analyzed and found to be in agreement with the above statements. The pendulum-like behavior in this sounding seems to be stimulated by the buoyant oscillation of the atmosphere. 相似文献
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309.
围绕北斗卫星导航系统中的伪距测量误差,全面分析系统的测量原理,提出系统误差指标体系的构建流程,构建基于误差层次分解方法的北斗卫星导航系统测量误差指标体系,指标体系由1个系统层指标、3个准则层指标、11个要素层指标和36个基础指标等51个指标组成。同时,结合实例,从卫星下行链路的绝对时延的测试需求,引出了绝对时延的测试问题,定义星载导航任务处理单元对外1PPS信号的输出口作为卫星的时间零点,给出需要测试的绝对时延的路径组成。根据目前系统的实际情况,通过每一部分的测试误差,求出整个绝对时延的测量误差精度。 相似文献
310.
Calibration of robotic drilling systems with a moving rail 总被引:2,自引:1,他引:2
Industrial robots are widely used in aircraft assembly systems such as robotic drilling systems. It is necessary to expand a robot's working range with a moving rail. A method for improving the position accuracy of an automated assembly system with an industrial robot mounted on a moving rail is proposed. A multi-station method is used to control the robot in this study. The robot only works at stations which are certain positions defined on the moving rail. The calibration of the robot system is composed by the calibration of the robot and the calibration of the stations.The calibration of the robot is based on error similarity and inverse distance weighted interpolation.The calibration of the stations is based on a magnetic strip and a magnetic sensor. Validation tests were performed in this study, which showed that the accuracy of the robot system gained significant improvement using the proposed method. The absolute position errors were reduced by about 85%to less than 0.3 mm compared with the maximum nearly 2 mm before calibration. 相似文献