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41.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2023,71(1):390-407
As the pace of human exploration and utilization of space continues to accelerate, space debris gradually becomes an inevitable problem affecting and threatening human space activities. When space debris strikes the spacecraft bulkhead, determining the impact source location timely and accurately is the foundation of the repair damage, and is also of great importance for the safety of astronauts' life. This paper analyzed the wave propagation law in thin plates, established a lightweight sensor array using PVDF (Polyvinylidene fluoride) circular thin-film sensors, and used a two-stage light-gas gun loading system to conduct hypervelocity collision localization experiments on impacting 2A12 aluminum plates to study the effects of sensor array radius and sensor size on localization results. The results show that the smaller the radius of the PVDF sensor array is, the more accurate the positioning result is under the premise of the same size of the PVDF circular film sensor array. On the premise of the same PVDF sensor array arrangement, the larger the PVDF circular membrane sensor is, the more accurate the positioning result is. ABAQUS finite element software is used to study the stress wave propagation of aluminum ball impacting aluminum plate at high speed, simulating space debris impacting spacecraft. The stress waveform obtained from the simulation is in good agreement with the experiment, which shows the accuracy of the numerical simulation method. 相似文献
42.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2023,71(1):785-802
CNES (Centre National d'Études Spatiales) acts, since its creation in 1961, as the French Space Agency and is a key leader in space research, and scientific and technical developments. Its involvement in a broad range of programs has positioned CNES as one of the most relevant national research agencies, leading efforts and initiatives in both European and international contexts. This article provides a review and analysis of the scientific and technical production of CNES, using as input the papers written by CNES staff referenced in the Scopus database. The period under study dates to 1964 and includes more than 10.000 documents. The study analyses measurable characteristics of CNES documents’ production: productivity, collaboration, and impact through citations. This paper provides a contribution aimed to gain a better understanding and characterisation of the scientific activity completed by Space agencies. 相似文献
43.
针对空间站所处太空环境的特殊性、对接机构对空间站正常运行的重要性,以及对航天器可靠性要求日益增加的问题,提出在对接控制系统中增加可靠性设计,实现整个机构的高质量、平稳运转。在完成正常控制功能的基础上,在系统中采用了四重冗余的工作机制,包括主备机双热备份、自动/手动控制模式切换、自动控制关闭指令双线发送和工作模式的三取二判断,对四重冗余设计的具体判断流程进行了详细的解释。对控制系统软件进行仿真验证,结果表明:本方法设计的对接控制系统具有高可靠性和故障容错能力。 相似文献
44.
空间机器人退步控制器设计 总被引:1,自引:0,他引:1
针对带任意节机械臂的空间机器人,采用退步法设计了基座姿态与机械臂受控的复合控制器。所设计的控制器以机械臂末端在工作空间中的位置和姿态、机械臂在关节空间中的关节角、关节角速度、基座姿态角和姿态角速度为反馈变量,可直接实现机械臂在工作空间的控制任务,避免了从工作空间到关节空间的运动学规划及Jacobian矩阵求导,同时,通过对基座的姿态控制能扩展机器人的功能,改善机械臂的动力学奇异特性。以某个带有6节机械臂的空间机器人为背景进行了数学仿真,验证了所设计的控制器的有效性。 相似文献
45.
深空探测自主导航与控制技术综述 总被引:10,自引:0,他引:10
深空探测自主导航与控制技术是深空探测任务成功实施的关键。基于开展深空探测自主导航与控制技术研究的迫切性,综合分析和评述深空探测自主导航与控制技术的研究进展,着重分析深空探测自主导航与控制的必要性和国外深空探测自主导航与控制技术的研究发展趋势,提出深空探测自主导航与控制的关键技术,根据分析,提出了发展深空探测自主导航与控制技术的建议. 相似文献
46.
利用C51编译器的BANK编译模式解决MCS-51系列单片机程序存储空间受64KB限制的问题,分析Keil C51编译器在BANK编译模式下的切换过程,提供一种软硬件的设计方法,并对设计的正确性进行了验证,从而解决了航天器设备典型单片机只能提供16B地址线对程序代码寻址的问题. 相似文献
47.
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49.
The short- and long-term effects of spacecraft explosions, as a function of the end-of-life re-orbit altitude above the geostationary orbit (GEO), were analyzed in terms of their additional contribution to the debris flux in the GEO ring. The simulated debris clouds were propagated for 72yrs, taking into account all the relevant orbital perturbations.The results obtained show that 6–7 additional explosions in GEO would be sufficient, in the long term, to double the current collision risk with sizable objects in GEO. Unfortunately, even if spacecraft were to re-orbit between 300 and 500km above GEO, this would not significantly improve the situation. In fact, an altitude increase of at least 2000km would have to be adopted to reduce by one order of magnitude the long-term risk of collision among geostationary satellites and explosion fragments. The optimal debris mitigation strategy should be a compromise between the reliability and effectiveness of spacecraft end-of-life passivation, the re-orbit altitude and the acceptable debris background in the GEO ring. However, for as long as the re-orbit altitudes currently used are less than 500km above GEO, new spacecraft explosions must be avoided in order to preserve the geostationary environment over the long term. 相似文献
50.
Spall caused by hypervelocity impacts at the lower range of velocities could result in significant damage to spacecraft. A number of polycrystalline alloys, used in spacecraft manufacturing, exhibit a pronounced anisotropy in their mechanical properties. The aluminium alloy AA 7010, whose orthotropy is a consequence of the meso-scale phase distribution or grain morphology, has been chosen for this investigation. The material failure observed in plate impact was simulated using a number of spall models. The Hugoniot elastic limit and spall strength have been studied as a function of orientation, and compared to experimental results. 相似文献