反馈结构模型及应用

反馈结构结构系统的排序原理是在递阶导次结构基础上提出来的，对于元素关系很复杂的系统，可能无法建立递阶层次结构模型，而反馈结构模型就为复杂关系提供了条件。在论述了建立反馈结构模型方法的基础上，对大型工程项目总设计单位的评审这一涉及因素多，关系复决策问题，进行了分析计算，在分析反馈结构模型时，借用了图论分析的方法，并建立了两类结构的运算模型，对反馈结构运算模型和递阶层次结构模型的排序结果进行了对比研究     

The GPS measured SITEC caused by the very intense solar flare on July 14, 2000

This work studies the sudden increases in total electron content of the ionosphere caused by the very intense solar flare on July 14, 2000. Total electron content (TEC) data observed from a Global Positioning System (GPS) network are used to calculate the flare-induced TEC increment, δTEC_f, and variation rate, dTEC_f/dt. It is found that both dTEC_f/dt and δTEC_f are closely related with the solar zenith angles. To explain the observation results, we derived a simple relationship between the partial derivative of the flare-induced TEC, ∂TEC_f/∂t, which is a good approximation for dTEC_f/dt, and the solar zenith angle χ, as well as the effective flare radiation flux I_f, according to the well-known Chapman theory of ionization. The derived formula predicted that ∂TEC_f/∂t is proportional to I_f and inverse proportional to Chapman function ch(χ). This theoretical prediction not only explains the correlation of dTEC_f/dt and δTEC_f with χ as shown in our TEC observation, but also gives a way to deduce I_f from TEC observation of GPS network. Thus, the present work shows that GPS observation is a powerful tool in the observation and investigation of solar flare effects on the ionosphere, i.e., the sudden ionospheric disturbances, which is a significant phenomenon of space weather.     

An Outline of Investigation of Space Medicine Problem and Its Mechanism

The human exploration of space is one of the great voyages of discovery in human history. For over forty years space exploration, human have gotten more profound knowledge about outer space and life phenomena, ranging from understanding and recognizing space to adapting and utilizing space. With these development, space medicine that aimed at studying effect of space environment on human health and ensuring the safety, health and effective working of human in space exploration, will become increasingly improved and matured.The contents of research will develop from the early phenomena observation of the effect of space environment on human physiology and biochemistry, and the effect definition, to the study of the mechanism of changes of cell, molecule, and gene, from the passive adaptation for space environment to taking the initiative countermeasures, in order to ensure the safety, health and effective working of astronauts during space flight.Space practices in the past forty years have confirmed that a variety of physiological and pathological changes have been found for organism exposed to space flight. These changes include cardiovascular dysfunction, bone loss,muscle atrophy, decline of immune function, endocrine function disorder and space motion sickness. In recent years, more attention has been focused on the study of the mechanism of these changes, especially the effects of space environment on cell, molecule and its gene expression. With the demand of China's manned space engineering task and continuous development, a series of studies on medical problem caused by space environment have been carried out.     

THEORETICAL AND EXPERIMENTAL STUDY ON THE PIEZOCERAMIC ACTUATING LAMINATE

压电陶瓷元件是目前在智能材料结构中广泛使用的一种驱动元件。建立驱动应力与控制信号之间的关系即传递驱动方程，对于分析压电陶瓷元件的驱动特性非常必要。本文以剪滞变形理论为基础，分析了压电陶瓷元件在驱动结构时的应力传递过程，建立了传递驱动模型；并以ＰＺＴ５型压电陶瓷元件驱动玻纤／环氧层合板为例对所建模型进行了实验验证。结果表明，建立的驱动模型与实际情况比较吻合。最后，根据实验结果和所建模型对影响压电陶瓷元件驱动层合板性能的一些主要参数作了分析。     

衬垫材料冲击特性测量数据的精度验证

本文提出了在冲击状态下对衬垫材料特性进行测量时，所获实验数据的精度验证方法，根据测量原理，作者首先进行了精度验证公式的推导，据以定义了精度验证因子。然后利用所获验证公式对实验测量数据进行了定量计算，并与验证因子的理论值加以对比。对比结果表明：作者在衬垫材料冲击特性的实验研究中所获测量数据具有足够的精度。本文所提出的精度验证方法亦可用于其它场合。     

机载导弹火控系统误差分析研究

论述了某型号飞机导弹火控系统精度误差分析理论和此误差分析系统的软件设计，给出了某型飞机导弹火控系统精度的数据模型和误差分析方法，从程度设想，软件结构设计，软件结构图和程序流程图诸方面对误差分析系统软件设计作了细致地分析和说明，该误差分析软件已成功地应用于某导弹火控系统精度试飞中，其设计经验可供有关人员借鉴和参考。     

视频会议中的音频编码方式研究

音频编码是视频会议系统的关键技术之一。文章对Ｈ２００系列标准的视频会议信号进行了音频编解码分析。通过对ＳＢ－ＡＤＰＣＭ编码技术的主要环节，镜像滤波器、自适应预测器和二次非均匀量化分析，反映出子带分割、分段预测与二次非均匀量化在音频编码中的作用。译码实验表明，译码是成功的，恢复出的伴音质量效果良好。     

Laves相金属间化合物Cr2 Nb的增韧方法

综述了Laves相Cr_2Nb金属间化合物的结构和变形机制及其韧化研究进展,重点评价了细晶增韧、软第二相增韧和合金化增韧这三种方法,指出了存在的问题及今后的研究方向。     

应变反馈式压电陶瓷微位移驱动器的研制

介绍了采用应变片测量压电陶瓷微位移驱动器位移的原理和设计思想，介绍了实验装置的结构，给出了实验结果，证明将应变片直接粘贴在压电陶瓷基体表面测量其位移的方法是可行性的；通过对压电陶瓷滞回特性的测定，提出了建立压电陶瓷的控制模型的基本思路。     

基于等概率随机法的航空发动机转子叶片排序优化

对于盘片分离的航空发动机转子,叶片排序影响初始不平衡量,容易导致振动超限。在转子装配环节,精准、高效的叶片排序优化对于提高装配质量和效率有重要意义。针对此问题,基于单个叶片的质量矩模型,建立单级转子初始不平衡量模型,提出叶片排序优化的目标函数,研究一种基于“等概率随机”的搜索算法,实现在资源、时间消耗和优化效果之间取得平衡。仿真和验证结果表明,该研究方法可以精准、高效地优化叶片装配排序。与传统方法相比,单级转子的初始不平衡量大幅降低,转子的装配品质得到极大提高,已在实际生产中取得显著的应用效益。