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1.
Changlong Jiang Jianping Xiong Xugang Zhang Huibo Jia Duanyi Xu 《Aerospace and Electronic Systems Magazine, IEEE》2003,18(11):31-34
Most sustained data recording systems in many real-time fields are based on tape equipments. We have developed an innovative sustained data recording system based on disk array which consists of Array Controller Module (ACM), String Controller Module (SCM) and Main Controller Module (MCM). This system has a better performance and higher reliability than the traditional tape recorder and can be used conveniently in many areas of data recording, storing, playback, and remote backup. This novel recording system has been used in radar data recorder for spacecraft orbit tracking and satellite remote sensing data recording successfully. 相似文献
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Loran-C is a pulsed, hyperbolic radio aid for long-range marine, air, and land navigation. The worldwide expansion of Loran-C, especially in Europe, has focused attention on carrier-wave interference to the system. The effects of a multiplicity of carrier-wave interferers (CWIs) on receiver timing measurement accuracy are considered. Both the phase tracking and the cycle-selection performance of receivers are quantified in terms of the probabilities that they will operate correctly within the arbitrarily set error limits. Characteristic functions (CFs) are used to compute these probabilities. Analyses and results are presented for typical situations. The relative sensitivity of the phase tracking and cycle-selection functions to interfering signals are discussed 相似文献
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基于软件文档可执行的想法,设计了一个适用于指称语义描述的可执行规范说明语言——JZC,并对其核心子集编译器进行了设计与开发。该语言设计采用了模式匹配、类型并置和构造函数等概念,使得抽象文法易于在程度中体现。模块概念的引入使得函数型语言书写的程序更加易懂和易于编写。作为对严格开发方法的一个尝试,JZC核心子集编译器的开发采用了该种方法,其中一个“结果正确性定理”的证明是开发过程的重点工作。本文通过一个示例语言简介JZC的语言特点,给出了编译器开发过程的一个描述框架和证明梗概 相似文献
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Heilbronn L Frankel K Holabird K Zeitlin C McMahan MA Rathbun W Cronqvist M Gong W Madey R Htun M Elaasar M Anderson BD Baldwin AR Jiang J Keane D Scott A Shao Y Watson JW Zhang WM Galonsky A Ronningen R Zecher P Kruse J Wang J Cary R 《Acta Astronautica》1998,42(1-8):363-373
In order to help assess the risk to astronauts due to the long-term exposure to the natural radiation environment in space, an understanding of how the primary radiation field is changed when passing through shielding and tissue materials must be obtained. One important aspect of the change in the primary radiation field after passing through shielding materials is the production of secondary particles from the breakup of the primary. Neutrons are an important component of the secondary particle field due to their relatively high biological weighting factors, and due to their relative abundance, especially behind thick shielding scenarios. Because of the complexity of the problem, the estimation of the risk from exposure to the secondary neutron field must be handled using calculational techniques. However, those calculations will need an extensive set of neutron cross section and thicktarget neutron yield data in order to make an accurate assessment of the risk. In this paper we briefly survey the existing neutron-production data sets that are applicable to the space radiation transport problem, and we point out how neutron production from protons is different than neutron production from heavy ions. We also make comparisons of one the heavy-ion data sets with Boltzmann-Uehling-Uhlenbeck (BUU) calculations. 相似文献
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简要介绍了成像链、成像系统和遥感系统的概念;对像质和像质差异的表征和度量、成像系统性能的表征等予以说明;重点探讨航天光学采样成像系统MTF的优化设计与MTFC问题,并给出讨论结果。 相似文献
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用等效网络法推导了考虑互耦影响时阵列的输出信号解析式和信噪比,仿真了不同阵元间距时,自适应直线阵的方向图和输出信噪比,得到了一些有用的结论。 相似文献
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有关压力传感器可靠性设计的若干问题 总被引:1,自引:0,他引:1
论述压力传感器的研制和应用中的经验教训。着重讨论从任务书要求,工程化设计,到生产过程有关压力信号特征、压力接口以及功能与结构相关性,功能与材料相关性等问题。 相似文献