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文章主要针对一种卫星数管中心计算机的软件需求,进行了操作系统和应用软件的设计和实现,并在数管分系统内部联试及与其它分系统接口匹配试验中对设计进行了验证。在软件的设计中,借鉴了空间数据系统咨询委员会的航天器星载接口业务(SOIS)和欧洲航天局的包应用标准(PUS),有助于软件的构件化和产品化。 相似文献
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Sarvan Kumar Sanjay Kumar A.K. Singh R.P. Singh 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
The Indo-Gangetic basin (IGB) extends 2000 km in length along NW–SE and has 400 km width, in the north the basin is bounded by towering Himalaya. High aerosol optical depth (AOD) is observed over the IGB throughout the year. The Himalaya restricts the transport of aerosols across Tibet and China. We have used ground based Kanpur and Gandhi College Aerosol Robotic Network (AERONET) stations and Multiangle Imaging SpectroRadiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) Terra level-3 AOD products for the years 2005–2009 to study the variability of aerosol over the Indo-Gangetic (IG) plains. An increase in both satellite-derived as well as ground observed aerosol loading during 2005–2009 has been found over major cities located in the IG plains. The correlation coefficients between AERONET and MISR data are found to be 0.70, 0.36 0.82, in contrast the correlation coefficients between AERONET and MODIS 0.49, 0.68, and 0.43, respectively during summer, winter and monsoon seasons. The AOD estimation using MISR is found to be close to AERONET data during summer and monsoon seasons, in contrast MODIS estimation is better during winter season. 相似文献
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随着遥感卫星观测数据量的日益增加,卫星数据传输能力已成为制约遥感卫星使用效能的瓶颈因素。为充分利用近地遥感卫星数据传输的链路资源,采用可变编码调制(VCM)技术,通过对星地数传信道条件的动态评估,在保证链路传输误码率和链路余量的前提下,自适应地进行当前信道条件下的最优编码调制方式切换,充分利用系统链路余量,提高卫星星地数据传输效能。利用该方法,对VCM数传链路效能进行仿真分析,与相同符号速率的固定编码调制(CCM)体制相比,VCM传输效能平均提升42.1%,可为遥感卫星的数传通道设计提供借鉴。 相似文献
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源源编译器是一种对源代码进行重构和分析的工具,在程序设计语言研究领域有着广泛的应用。给出了一种源源编译的控制流结构优化方法。方法结合编译结构分析,对于可化简合并的典型控制流结构,进行结构分析;经数据流分析满足优化条件后,实现基本块的合并。优化后程序的结构更加清晰,可读性更好。方法在SUIF编译器上实现,经使用Olden基准测试程序试验,有效提高了源代码的翻译质量。 相似文献
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Xiuqiang Jiang Shuang Li Xiangyu Huang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(5):1342-1358
Supposing future orbiting and landing collaborative exploration mission as the potential project background, this paper addresses the issue of Mars entry integrated navigation using radio beacon, flush air data sensing system (FADS), and inertial measurement unit (IMU). The range and Doppler information sensed from an orbiting radio beacon, the dynamic pressure and heating data sensed from flush air data sensing system, and acceleration and attitude angular rate outputs from an inertial measurement unit are integrated in an unscented Kalman filter to perform state estimation and suppress the system and measurement noise. Computer simulations show that the proposed integrated navigation scheme can enhance the navigation accuracy, which enables precise entry guidance for the given Mars orbiting and landing collaborative exploration mission. 相似文献
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L.H. Deng B. Li Y.Y. Xiang G.T. Dun 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The mid-term periodicities of polar faculae are studied separately for the total disk, northern and southern hemispheres of the Sun for a time interval from 1951 August to 1998 December. Apart from the 11-year Schwabe cycle which is the fundamental period and is found in all of the three time series, the following prominent results are found: (1) the rotational periodicity of solar activity at high latitudes is approximately from 28 to 32 days; (2) a large number of quasi-periods appearing in low-latitude solar activity (annual variation, 1.3–1.7 years, quasi-biennial oscillation, and 4–5 years) also exist in polar faculae; (3) the periodicities on both hemispheres are not identical. 相似文献
1000.
Track association of multi-target has been recognized as one of the key technologies in distributed multiple-sensor data fusion system,and its accuracy directly impacts on the performance of the whole tracking system.A multi-sensor data association is proposed based on aftinity propagation(AP)algorithm.The proposed method needs an initial similarity,a distance between any two points,as a parameter,therefore,the similarity matrix is calculated by track position,velocity and azimuth of track data.The approach can automatically obtain the optimal classification of uncertain target based on clustering validity index.Furthermore,the same kind of data are fused based on the variance of measured data and the fusion result can be taken as a new measured data of the target.Finally,the measured data are classified to a certain target based on the nearest neighbor ideas and its characteristics,then filtering and target tracking are conducted.The experimental results show that the proposed method can effectively achieve multi-sensor and multi-target track association. 相似文献