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801.
最短路径的编程实现   总被引:2,自引:0,他引:2  
本文介绍了求最短路径的Floyd算法的设计思路及C语言编程实现。  相似文献   
802.
A self-consistent time-dependent, two-dimensional MHD model with a realistic energy equation is developed to understand the origin of bright coronal emission accompanying the occurrence of a new bipolar magnetic region. The motivation for this study is the interpretation of anticipated observations to be made by the SOHO mission.Purple Mt. Obser., PRC  相似文献   
803.
通过对网络广告发展的现状和问题分析及网络广告策划方法探讨,提出了提高网络广告策划质量的新思路。  相似文献   
804.
安东  胡兆丰 《飞行力学》1995,13(2):58-62
给出了一类解耦非线性控制系统稳定跟踪设定线性系统的建议性解法。简单讨论了不同反馈解耦问题的区别,解耦系统极点配置的条件和解耦后的非线性系统保证稳定性的一种途径,并且给出了所用的方法适用的范围和一个建议性判据。  相似文献   
805.
Multi-spacecraft tracing of the high latitude magnetopause (MP) and boundary layers and Interball-1 statistics indicate that:
1. (a) The turbulent boundary layer (TBL) is a persistent feature in the region of the cusp and ‘sash’, a noticeable part of the disturbances weakly depends on the interplanetary magnetic field By component; TBL is a major site for magnetosheath (MSH) plasma penetration inside the magnetosphere through percolation and local reconnection.
2. (b) The TBL disturbances are mainly inherent with the characteristic kinked double-slope spectra and, most probably, 3-wave cascading. The bi-spectral phase coupling indicates self-organization of the TBL as the entire region with features of the non-equilibrium multi-scale and multi-phase system in the near-critical state.
3. (c) We've found the different outer cusp topologies in summer/winter periods: the summer cusp throat is open for the decelerated MSH flows, the winter one is closed by the distant MP with a large-scale (several Re) diamagnetic ‘plasma ball’ inside the MP; the ‘ball’ is filled from MSH through patchy merging rather than large-scale reconnection.
4. (d) A mechanism for the energy release and mass inflow is the local TBL reconnection, which operates at the larger scales for the average anti-parallel fields and at the smaller scales for the nonlinear fluctuating fields; the latter is operative throughout the TBL. The remote from TBL anti-parallel reconnection seems to happen independently.

References

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Merka, J., Safrankova, J., Nemecek, Z., Fedorov, A., Borodkova, N., Savin, S. and Skalsky, A., 2000. High altitude cusp: Interball observations. Adv. Space Res. 25, pp. 1425–1434. Article | PDF (915 K) | View Record in Scopus | Cited By in Scopus (22)
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Zelenyi, L.M. and Milovanov, A.V., 1998. Multiscale magnetic structure of the distant tail: self-consistent fractal approach. In: New Perspectives on the Earth MagnetotailGeophys. Monograph 105, AGU, Washington DC, pp. 321–338.
  相似文献   
806.
嫦娥工程是我国发展深空探测走出的关键一步,意义重大。为和平应用空间资源,加强国际间的合作,在嫦娥工程中较完整地采用了CCSDS标准数据结构。文中介绍嫦娥工程数据接收分系统的主要功能、指标、组成以及目前的进展状态。  相似文献   
807.
无人机机载天线单轴稳定平台设计与实现   总被引:2,自引:0,他引:2  
针对无人机机载垂直极化天线电轴受飞机姿态影响的问题 ,介绍一种天线稳定平台的设计方法。文中讨论其机械结构设计原理、选择伺服机构电机时的力矩计算方法、控制电路硬件结构和软件实现方案  相似文献   
808.
文章介绍了高级惯性参考球的结构特点,给出连续自对准和自校准的部分研究结果,其中的软件部分可方便地用在导弹性能测量系统(MPMS)中。文章还给出了两套惯性测量装置的评价方法的数学公式,且建议采用新的数据处理方法:卡尔曼回归算法。最后,分析了采用MPMS方法的可能优点。  相似文献   
809.
膏体推进剂和固体推进剂药浆稳态燃烧研究   总被引:1,自引:1,他引:1  
在固体推进剂BDP燃烧模型基础上,引入膏体推进剂燃烧效应这一新参数将模型推广于膏体推进剂和固体推进剂药浆燃烧研究,模型考虑了氧化剂粒度分布,组分配比,催化剂性有和膏体推进剂燃烧热效应等对燃速的影响,以及药浆固化有前后燃速差别,还有靶线法测量了某批次复合推进剂药浆固化前后燃速变化,论文结果可用于膏体推进剂的配方和性能预测,以及利用药浆燃速预示固化后推进剂燃速,监控固体推进剂制造质量。  相似文献   
810.
宋力平 《上海航天》1997,14(4):20-25
讨论简单雷达信号存在的主要问题和单一波形信号在应用中的几种主要限制。根据弹炮结合系统对制导火控雷达作用距离范围等要求,提出一种码分,频分和时分雷达信号设计,它能够很好地满足这种要求,并可大大提高雷达反侦察和抗干扰能力。  相似文献   
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