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Design of Embryo-electronic Systems Capable of Self-diagnosing and Self-healing and Configuration Control 总被引:1,自引:0,他引:1
As aerospace vehicles travel in a hellish environment, the reliability of the measuring and controlling systems has played a critical role in the credibility of a whole airborne system. Embryo-electronic system is a bionic hardware capable of self-diag- nosing and self-healing. This article presents a new approach to design embryo-electronic systems and introduces their bionic principles, system structures and fault-tolerant mechanism. As the current methods cannot meet the requirements for large-scale embryo-electronic systems, this article advances a new shift-register-based configuration memory of embryonic system to solve the problem by using the inter-cell communication to reduce the gene storage capacity of a single cell. The article designs an overall structure of the shift-register-based configuration memories of the embryonic system and connects them into a chain structure. The article also designs an inner circuit of the cell, the control of shift-register-based configuration memory and the way of runtime dynamic configuration. The simulation of field programmable gate array (FPGA) evidences the realizability of the proposed design. Compared to the SRAM-based one, this memory can save 90% of the area when constructing embryonic systems larger than 128 × 128 under the same condition. 相似文献
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本文对新型粘弹性阻尼器的设计计算及模具设计进行了全面的描述和分析,并以某型机相关参数为原始数据走了一个全过程。 相似文献
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给出了一种通过静态电阻应变仪及外旋式粘度装置测量流体粘度的方法。由同步电动机带动外圆筒旋转剪切流体,从而将粘性力传递给内筒,内筒与圆轴相连。粘性力产生的扭矩使圆轴产生应变,在圆轴表面黏贴电阻应变片,通过合理组桥将应变显示在静态电阻应变仪上,根据应力应变关系计算出扭矩,从而计算出流体的动力粘度。 相似文献
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矩形薄膜和充气管的屈曲及后屈曲行为分析 总被引:1,自引:0,他引:1
对矩形薄膜及充气管的屈曲及后屈曲过程进行了分析。首先基于矩形薄膜褶皱区域的应力平衡关系,得到了矩形剪切薄膜褶皱的波长及幅度的表达式,并考虑了微小的初始张力的作用。基于稳定性理论建立了薄膜褶皱的数值分析方法,通过实验的方法对分析结果进行了验证。分析表明矩形剪切薄膜的屈曲过程是分枝点平衡问题。对于充气管的分析是基于张力场理论建立了其扭转临界扭矩的表达式,并与数值分析的结果进行了对比分析,分析表明充气管的屈曲过程是极值点平衡问题。通过对比分析,两种结构形式的分析结果与数值分析的结果基本符合。建立的分析方法能够有效地进行薄膜结构的屈曲及后屈曲过程的分析。 相似文献
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故障预测与健康管理(PHM)技术的现状与发展 总被引:40,自引:5,他引:40
结合故障预测与健康管理(PHM)的技术发展过程,阐述了PHM的应用价值。论述了PHM技术系统级应用问题,提出了故障诊断与预测的人-机-环完整性认知模型,并依此对蓬勃发展的故障诊断与故障预测技术进行了分类与综合分析,给出了PHM技术的发展图像。针对故障诊断与预测的不确定性特征,对故障诊断与预测技术的性能要求、定量评价与验证方法进行了分析。最后,以PHM技术的工程应用为线索,提出了PHM技术发展中的几个问题。 相似文献
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D. K. Nadyozhin 《Space Science Reviews》1995,74(3-4):455-461
The high temperature sensitivity of thermonuclear reactions and the neurrino emission at the final stages of stellar evolution (urca process) are the most crucial Gamow's contribution to the physics and evolution of stars. G. Gamow made one of a few first attempts in astrophysics to get a comprehensive picture of stellar evolution from the main sequence (thenormal stars in his terminology) through the formation of white dwarfs, gravitational collapse of stellar cores and supernova explosions. 相似文献
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在研制基于单片机的智能仪器“导爆索、雷管爆速校准仪”的过程中,引入可编程逻辑器件来处理超过单片机处理能力范围的高速信号,并开发了一套有效结合单片机和可编程逻辑器件的方法。 相似文献
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The properties of magnetohydrodynamic waves and instabilities of laboratory and space plasmas are determined by the overall
magnetic confinement geometry and by the detailed distributions of the density, pressure, magnetic field, and background velocity
of the plasma. Consequently, measurement of the spectrum of MHD waves (MHD spectroscopy) gives direct information on the internal
state of the plasma, provided a theoretical model is available to solve the forward as well as the inverse spectral problems.
This terminology entails a program, viz. to improve the accuracy of our knowledge of plasmas, both in the laboratory and in
space. Here, helioseismology (which could be considered as one of the forms of MHD spectroscopy) may serve as a luminous example.
The required study of magnetohydrodynamic waves and instabilities of both laboratory and space plasmas has been conducted
for many years starting from the assumption of static equilibrium. Recently, there is a outburst of interest for plasma states
where this assumption is violated. In fusion research, this interest is due to the importance of neutral beam heating and
pumped divertor action for the extraction of heat and exhaust needed in future tokamak reactors. Both result in rotation of
the plasma with speeds that do not permit the assumption of static equilibrium anymore. In astrophysics, observations in the
full range of electromagnetic radiation has revealed the primary importance of plasma flows in such diverse situations as
coronal flux tubes, stellar winds, rotating accretion disks, and jets emitted from radio galaxies. These flows have speeds
which substantially influence the background stationary equilibrium state, if such a state exists at all. Consequently, it
is important to study both the stationary states of magnetized plasmas with flow and the waves and instabilities they exhibit.
We will present new results along these lines, extending from the discovery of gaps in the continuous spectrum and low-frequency
Alfvén waves driven by rotation to the nonlinear flow patterns that occur when the background speed traverses the full range
from sub-slow to super-fast.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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设计实现了一个用于解决DDN(Digital Data Net)网络管理不足之处的新系统——DDN状态监控系统.详细论述了该系统的设寸思路和软件结构,采用了数据库、网络轮询等一系列有效的技术手段来解决DDN网络管理的不足,指出了该系统的技术创新点。 相似文献
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导航信息显示管理计算机通过人机交互向飞机驾驶人员提供各种飞行状态及飞行指引参数,本文以某飞机测控平台辅助导航显示管理计算机设计实现为例,介绍了导航信息显示管理计算机的工作方式、工作流程并探讨了导航信息显示管理计算机的设计特点和关键技术。 相似文献
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论新型工业化战略与循环经济范式的产业重构 总被引:2,自引:0,他引:2
刘力 《郑州航空工业管理学院学报(管理科学版)》2008,26(5):82-86
走新型工业化道路与发展循环经济是新时期我国转变经济发展方式的战略选择,并共同面临产业结构调整与转型的现实问题。文章从新型工业化战略可以引导循环经济发展方向,而循环经济的模式选择也离不开经济发展战略推动这一认识前提出发,分别从循环经济的技术模式决定产业转型的必要性,以及产业转型的要素供给与需求等现实条件对循环经济发展的障碍进行分析,提出用新型工业化战略引导循环经济发展,以及产业转型的相关政策思考。 相似文献
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Franco Verniani 《Space Science Reviews》1969,10(2):230-261
This paper is a review of the present knowledge on the structure of meteoroids.A summary of the evidence concerning the common occurrence of fragmentation among both photographic and radio meteors is given first. Then, an attempt is made to examine all the present observational, theoretical and laboratory data on the luminous and ionizing efficiencies of meteors, with the aim of establishing a mass scale. This allows the computation of the bulk density of meteoroids, which, on the average, turns out to be about 0.3 g/cm3.The paramount importance of progressive fragmentation, the behavior of abrupt-beginning meteors and the low density of nearly all meteoroids (even of those of relatively large sizes) support a porous and fragile structure for most of these particles. In turn, the crumbly structure and the cometary origin confirm Whipple's theory of comets and meteor production. A critical analysis of recent papers proposing different conclusions shows that the new theories always arrive at results which do not agree with well-established observational data. 相似文献
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牛少伟 《沈阳航空工业学院学报》2012,29(2):81-85
通过对常见的几种轰燃定义的对比分析,对轰燃进行了新的定义,认为轰燃是室内火灾发展到一定阶段引起非连续介质着火燃烧的现象;在此基础上,根据燃烧学原理提出了轰燃发生的机理,即可燃挥发份和高温烟气层接触发生的剧烈氧化还原反应;并提出了预测轰燃的通用判据,即火灾时室内其它可燃物热解产生的可燃挥发份迅速和空气混合,达到其着火浓度下限且接触到超过可燃物自燃点的高温烟气层。 相似文献
18.
Michael F. A’Hearn 《Space Science Reviews》2008,138(1-4):237-246
The Deep Impact mission revealed many properties of comet Tempel 1, a typical comet from the Jupiter family in so far as any comet can be considered typical. In addition to the properties revealed by the impact itself, numerous properties were also discovered from observations prior to the impact just because they were the types of observations that had never been made before. The impact showed that the cometary nucleus was very weak at scales from the impactor diameter (~1 m) to the crater diameter (~100 m) and suggested that the strength was low at much smaller scales as well. The impact also showed that the cometary nucleus is extremely porous and that the ice was close to the surface but below a devolatilized layer with thickness of order the impactor diameter. The ambient observations showed a huge range of topography, implying ubiquitous layering on many spatial scales, frequent (more than once a week) natural outbursts, many of them correlated with rotational phase, a nuclear surface with many features that are best interpreted as impact craters, and clear chemical heterogeneity in the outgassing from the nucleus. 相似文献
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变后掠变展长翼身组合体系统设计与特性分析 总被引:2,自引:0,他引:2
为了探索可变形飞行器气动、结构和控制关键技术,在可变后掠角及展长的翼身组合体风洞试验模型系统设计与特性分析方面开展了研究。系统设计包括总体方案设计、近似理论分析与计算流体力学(CFD)数值模拟、结构与控制技术集成;特性分析包括结构特性、控制特性、定常与非定常气动特性的测试及其分析。结果表明:大尺度变形能显著改变飞行器的升力、阻力和升阻比等气动特性,进而使可变形飞行器能适应多种环境和任务,因而在全飞行周期中比传统固定外形飞行器具有更优的性能。 相似文献
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C. S. Arridge N. Andr�� C. L. Bertucci P. Garnier C. M. Jackman Z. N��meth A. M. Rymer N. Sergis K. Szego A. J. Coates F. J. Crary 《Space Science Reviews》2011,162(1-4):25-83
The formation of Titan??s induced magnetosphere is a unique and important example in the solar system of a plasma-moon interaction where the moon has a substantial atmosphere. The field and particle conditions upstream of Titan are important in controlling the interaction and also play a strong role in modulating the chemistry of the ionosphere. In this paper we review Titan??s plasma interaction to identify important upstream parameters and review the physics of Saturn??s magnetosphere near Titan??s orbit to highlight how these upstream parameters may vary. We discuss the conditions upstream of Saturn in the solar wind and the conditions found in Saturn??s magnetosheath. Statistical work on Titan??s upstream magnetospheric fields and particles are discussed. Finally, various classification schemes are presented and combined into a single list of Cassini Titan encounter classes which is also used to highlight differences between these classification schemes. 相似文献