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731.
本文介绍了嵌入式操作系统WinCE.Net的USB总线驱动框架,以网眼摄像头驱动程序的设计为例,详细介绍了基于流接口驱动模型设计USB设备驱动程序的过程。测试表明,该设计方案是可行的。  相似文献   
732.
通过水平定向钻在市政工程中的广泛应用,水平定向钻施工越来越显示出它的优势,其施工对周围环境的影响需要评估。为此,对水平定向钻小直径管道施工过程引起的力学效应进行了讨论,重点探讨了拉力、扭矩和泥浆的影响,同时通过分析沉降位移监测值,就具体施工过程所带来的影响进行了讨论,得出了有益的结论。  相似文献   
733.
深空探测任务面临辐射与温度变化综合作用的恶劣环境,易导致作为航天器电子系统主要组成的CMOS集成电路发生单粒子锁定效应。着眼于在轨应用需求,针对体硅工艺SRAM器件进行了高温环境单粒子锁定试验研究,在不同电压和温度条件下开展重离子辐照试验,结果表明,随着器件工作电压的升高,单粒子锁定敏感性增加;随着温度升高,单粒子锁定截面增加,从常温到125 ℃的增幅约为1个数量级:即高温高电压下更易触发器件单粒子锁定效应。  相似文献   
734.
在航天器真空热试验中,常选用红外加热笼作为外热流模拟装置。为提高外热流模拟的准确性,红外加热笼需要对航天器进行全表面覆形。文章针对如何确认外热流模拟装置与航天器的结构匹配性这个难题,依托三维扫描技术,建立了一套数字化结构匹配方法,解决了多站测量拼接误差累积、三维扫描仪参数优化选择2个技术难点,使三维扫描和逆向建模过程引入的几何误差不超过10 mm。该数字化结构匹配方法的实际应用结果表明,外热流模拟装置与航天器的配装成功率达到100%,实际安装状态与仿真结果吻合度较好。  相似文献   
735.
Numerical investigations are conducted to explore the aerodynamic characteristics of three-dimensional Co-Flow Jet(CFJ) wing with simple high-lift devices during low-speed takeoff and landing. Effects of three crucial parameters of CFJ wing, i.e., angle of attack, jet momentum and swept angle, are comprehensively examined. Additionally, the aerodynamic characteristics of two CFJ configurations, i.e., using open and discrete slots for injection, are compared. The results show that applying CFJ te...  相似文献   
736.
介绍了热流传感器的主要应用场合,说明了建立热阻式热流传感器校准装置的重要意义,论述了热阻式热流传感器的测量原理及其校准方法,对保护热板法的国内外研究现状进行了总结。设计了保护热板法校准装置,实现热阻式热流传感器量值的准确溯源。  相似文献   
737.
为了有效防止损伤和环境腐蚀,需要对军用航空燃气涡轮发动机进行良好地包装运输设计。重点分析研究美国发动机的包装运输设计,包括规范与标准、运输装置与运输方式、运输车运输、运输罐运输、托架运输等。简要介绍中国的发动机包装运输设计,比较美国与中国的发动机包装运输设计。提出借鉴美国设计完善和改进中国战斗机发动机包装运输设计的建议。  相似文献   
738.
Electrochemical drilling(ECD) provides an alternative technique for drilling multiple small holes in difficult-to-machine materials in numerous industrial applications such as for aeroengines. The value and fluctuation of electrolyte flowrate can seriously affect the machining stability and hole quality in ECD. In particular, when drilling multiple holes, the distribution and fluctuations of the electrolyte flowrate in each channel could influence the uniformity of the electrolyte flowrate among...  相似文献   
739.
《中国航空学报》2023,36(2):292-303
Chang’e-5 explorer successfully acquired lunar regolith core samples from depths of greater than 1 m of lunar surface. This study analyzed the lunar core drilling process based on the telemetry data, image information, and returned samples to optimize the sampling device design and enhance the understanding of the lunar regolith. In particular, a prediction method for the projected drilling path and local terrain fitting of drilling dip angle was proposed based on the flight events recorded during the core drilling process and the image information acquired before, during, and after sampling. The results revealed that the drilling dip angle of Chang’e-5 was approximately 2.3°, and the deviation of the drilling length and depth was less than 2 mm. For continuous drilling, a fusion method based on telemetry data and image information was applied to determine the demarcation point of drilling with and without the lunar soil. The position of the demarcation point implied that the drilling point remained at approximately 6 mm loose soil, thereby lagging the action of the force response. Additionally, a characteristic parameter comparison method was proposed for the lunar and ground drilling to analyze the status of the lunar soil. Furthermore, the analysis results revealed that the majority of the Chang’e-5 drilling samples were derived from 0–73.8 cm below the lunar surface and few samples were extracted below 73.8 cm, as the drilling encountered several rocky regions. Moreover, the drilling point exhibited two prominent stratification variations at ~28.7 cm and ~70 cm below the lunar surface. Ultimately, the preliminary relationship between sample dissected position in soft tube and drilling displacement was analyzed. The segmented estimation results can support research on subsurface lunar soil.  相似文献   
740.
《中国航空学报》2023,36(3):202-211
The safety and reliability of space connection and separation device has become a key issue due to the increasing service span of deep space exploration mission. The long-term preload relaxation (a key failure mode) of connection and separation devices is focused in this paper. A series of tests have been designed and implemented to investigate the preload relaxation regulation and a comprehensive method has been constructed to analyze and predict the reliable lifetime of the device. The two-stage preload relaxation law of the device is found and reasonably considered. Due to the different relaxation mechanism, the first-stage preload relaxation is assessed based on the working-condition test results, and the second-stage preload relaxation is characterized by accelerated test results. Finally, the service reliability and reliable life are evaluated. The experiment and assessment results demonstrate the reasonability and effectiveness of the proposed method which can achieve long-service reliability analysis for space connection and separation device within limited time.  相似文献   
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