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531.
China has great progress in the technology and application of ocean color remote sensing during 2004-2006. In this report, firstly, four major technical advances are displaying, including (1) the vector radiative transfer numerical model of coupled ocean-atmosphere system; (2) the atmospheric correction algorithm specialized on Chinese high turbid water; (3) systematical research of hyper-spectrum ocean color remote sensing; (4) local algorithms of oceanic parameters, like ocean color components, ocean primary productivity, water transparency, water quality parameters, etc. On the foundation of technical advances, ocean color remote sensing takes effect on ocean environment monitoring, with four major kinds of application systems, namely, (1) the automatic multi-satellites data receiving, processing and application system; (2) the shipboard satellite data receiving and processing system for fishery ground information; (3) Coastal water quality monitoring system, integrating satellite and airborne remote sensing technology and ship measurement; (4) the preliminary system of airborne ocean color remote sensing application system. Finally, the prospective development of Chinese ocean color remote sensing is brought forward. With Chinese second ocean color satellite (HY-1B) orbiting, great strides will take place in Chinese ocean color information accumulation and application.  相似文献   
532.
文中着重介绍某型飞机发动机加力控制系统附件压比调节器真空钎焊用钎料BVAg-1的研制、工艺试验过程和工艺参数匹配。成功地解决了焊接与材料热处理加工温度之间的制约矛盾,提高了产品的焊接可靠性。  相似文献   
533.
The main aim of the present study was to examine the feasibility of the EO-1 Hyperion data in discriminating and mapping diagnostic alteration minerals around porphyry copper deposits (PCDs), verified by field surveys and laboratory analyses. A partial sub-pixel method, mixture tuned matched filtering (MTMF), was implemented on a pre-processed and calibrated Hyperion dataset. The tested area is situated at the Central Iranian Volcano-Sedimentary Complex, where abundant porphyry copper deposits like Sarcheshmeh, Darrehzar, and Sereidun are located. The characteristic alteration minerals identified by Hyperion data included biotite, muscovite, illite, kaolinite, goethite, hematite, jarosite, pyrophyllite, and chlorite. Discrimination of these minerals especially biotite and iron oxide (hematite and goethite) can provide valuable evidences for PCD exploration projects. Results revealed that Hyperion data prove to be powerful in discriminating and mapping various types of alteration zones while the data were subjected to adequate pre-processing.  相似文献   
534.
Dating back to the Apollo and Skylab missions, it has been reported that astronauts suffered from bacterial and viral infections during space flight or after returning to Earth. Blood analyses revealed strongly reduced capability of human lymphocytes to become active upon mitogenic stimulation. Since then, a large number of in vitro studies on human immune cells have been conducted in space, in parabolic flights, and in ground-based facilities. It became obvious that microgravity affects cell morphology and important cellular functions. Observed changes include cell proliferation, the cytoskeleton, signal transduction and gene expression. This review gives an overview of the current knowledge of T cell regulation under altered gravity conditions obtained by in vitro studies with special emphasis on the cell culture conditions used. We propose that future in vitro experiments should follow rigorous standardized cell culture conditions, which allows better comparison of the results obtained in different flight- and ground-based experiment platforms.  相似文献   
535.
从人机工效基本原理出发,在对国内外适航规章和行业标准解读的基础上,结合触控技术自身特征,对触控显示系统人机工效设计的影响因素进行分析,并综合运用了改进德尔菲法和改进层次法,初步构建了民机触控显示系统人机工效评估指标体系,可为系统的设计与评估提供借鉴.  相似文献   
536.
The European Stratospheric Balloon Observatory (ESBO) initiative aims at simplifying the access to stratospheric balloon missions. We plan to provide platforms and support with instrument design in order to support scientists. During the design process, the inevitable question of qualification for the harsh flight conditions arises. Unfortunately, there is no existing standard for qualification of stratospheric ballooning hardware. Thus, we developed a qualification procedure for use within ESBO and similar projects.In this paper, we present our analysis of the environmental conditions in the stratosphere. While conditions at typical balloon float altitudes are similar to the space environment, there are also some relevant differences. For example, the thermal environment is dominated by radiation and thermal conduction, but the remaining atmosphere still supports a certain amount of convection. The remaining atmospheric pressure in the stratosphere also leads to reduced arcing distances. Vibrational loads are far less than for space missions, but quasi-static or shock loads may occur. The criticality of radiation increases with mission duration.Based on the environmental conditions, we present the qualification procedures for ESBO, which are based on the European Cooperation for Space Standardization (ECSS) standards for space systems. Overtesting against too high requirements leads to overengineering, driving mission cost and mitigating the advantages of balloons over space missions. Therefore, we modified the ECSS standards to fit typical scientific ballooning missions over several days at altitudes up to 40 km. Furthermore, we analyzed design rules for space systems with regard to their relevance for scientific ballooning, including material and component selection. We present the experience from the hardware qualification process for the ESBO prototype STUDIO (Stratospheric UV Demonstrator of an Imaging Observatory). Even though boundary conditions are different for each individual mission, we aimed for a broader approach: We investigated more general requirements for scientific ballooning missions to support future flights.  相似文献   
537.
基于萤火一号技术的自主火星探测器方案   总被引:1,自引:0,他引:1  
提出了基于萤火一号(YH-1)火星探测器技术的自主火星探测器方案,可携带多种有效载荷在准太阳同步圆轨道上对火星进行科学探测。该方案具有可实现性强、成本低、研制周期短等特点,并能满足火星探测后续工程中的环绕器设计要求,利于我国火星探测的长远发展。利用长征三号乙运载火箭,在西昌卫星发射中心就可实现2013/2016年的我国自主火星探测。  相似文献   
538.
539.
不透水面是评估城市化进程和评价城市环境的重要参考指标,研究城市不透水面的空间覆盖程度对城市生态环境保护、宜居城市建设具有重要意义。本文以“珠海一号”高光谱影像为数据源、珠海市陆域为研究区域,选取支持向量机和随机森林机器学习算法,结合光谱特征,实现城市不透水面信息提取。结果表明:使用“珠海一号”高光谱数据提取不透水面可行性较强,且支持向量机算法更适用于“珠海一号”不透水面提取,总体精度和Kappa系数分别达到92.4%、0.78;基于“珠海一号”高光谱数据进行城市不透水面提取,可为城市规划建设、分析城市土地扩张、评估城市灾害风险提供可靠理论依据和数据支撑。  相似文献   
540.
以籼型三系不育系宜香1A、Ⅱ-32A、冈46A和恢复系宜恢7633、宜恢7008、宜恢1525等为材料,研究了亲本和杂交后代的倒伏指数.结果表明,Ⅱ-32A的倒3节间抗倒能力极显著强于宜香1A;冈46A倒3节间的抗倒能力显著强于宜香1A;宜香1A和Ⅱ-32A所配品种倒3节间抗倒能力相当,都极显著优于冈46A 所配品种倒3节间抗倒能力.母本及其所配品种的倒2节间和倒1节间倒伏指数无明显差异.  相似文献   
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