改进层次聚类法在复合材料敲击检测中的应用

伴随复合材料的迅速发展,其在航空航天方面的应用也日益普遍,但因复合材料的各向异性,在制造过程中会导致某些缺陷的产生。敲击检测作为一种实时原位的无损检测,在复合材料的检测中效果明显。由于敲击检测尚未找到合理的数据处理方法,所以其应用范围受到限制。从解决敲击检测数据处理方法的角度出发,提出将改进层次聚类法应用于敲击检测中,并在应用实例环节对该方法进行了应用,通过实验结果对比,表明改进层次聚类方法可以解决敲击检测数据处理的问题。     

大型客机一体化试飞改装设计方法研究

研究了大型客机试飞改装的要求和特点,提出了一体化试飞改装的设计方法,结合其在型号研制过程中的具体应用情况,具体阐述了一体化改装设计的方法及关键技术点。     

通用型题库系统（TH1.0）的设计

介绍了一个集题库管理、试卷管理及ＷＰＳ排版打印于一体的题库系统的设计与实现，给出了系统的结构与主要功能，提供了一个可支持要求各异的不同学科进行题库生成的实用性和通用性较强的计算机辅助教学的工具。     

攻角试飞测试基准的误差修正

阐述了攻角测量误差的成因和攻角试飞校准的必要性。选定机头空速管攻角传感器为攻角试飞的测试基准，分析其攻角探测特性，并运用细长旋成体理论重点计算了机体绕流对攻角测量的影响量。探讨了攻角试飞测试基准的误差修正问题。     

藜蒿中绿原酸溶剂提取方法研究

应用醇溶剂回流法提取藜蒿中绿原酸，通过正交试验，对藜蒿中绿原酸进行溶剂提取条件的优化研究，并分剐讨论了各因素对绿原酸提取率的影响。实验表明，乙醇浓度70％、12倍的提取剂用量、温度85℃、提取时间4h、提取两次为乙醇溶剂提取藜蒿中绿原酸的最佳条件，总绿原酸提取率为1.24％。     

200km/h动力分散型电动旅客列车组车体表面压力分布试验研究

阐述了对我国首列200km/h动力分散型电动旅客列车组(先锋号列车)车体表面压力分布测试情况,对测量结果进行了较为详细的分析,最后用流场计算软件CFX对先锋号列车周围流场进行了数值模拟计算,并将计算结果与测量结果进行了对比,两者有较好的一致性。该研究结果可为空调装置及电器设备冷却风道进排风口位置的选取提供科学依据。     

Modeling Multifractality of the Solar Wind

The question of multifractality is of great importance because it allows us to investigate interplanetary hydromagnetic turbulence. The multifractal spectrum has been investigated with Voyager (magnetic field) data in the outer heliosphere and with Helios (plasma) data in the inner heliosphere. We use the Grassberger and Procaccia method that allows calculation of the generalized dimensions of the solar wind attractor in the phase space directly from the cleaned experimental signal. We analyze time series of plasma parameters of the low-speed streams of the solar wind measured in situ by Helios in the inner heliosphere. The resulting spectrum of dimensions shows a multifractal structure of the solar wind attractor. In order to quantify that multifractality, we use a simple analytical model of the dynamical system. Namely, we consider the generalized self-similar baker’s map with two parameters describing uniform compression and natural invariant measure on the attractor of the system. The action of this map exhibits stretching and folding properties leading to sensitive dependence on initial conditions. The obtained solar wind singularity spectrum is consistent with that for the multifractal measure on the weighted baker’s map.     

基于二项分布的装备状态质量诊断试验评估指标研究

提出了通过诊断方法获取装备状态质量特性指标值的思想，解决了统计特性不明显的小样本集装备获取状态质量特性指标的难题；规范了装备状态质量诊断试验的条件；在装备质量评估领域首次提出了评价装．备诊断试验效果的确诊率、负确诊率、误诊率、漏诊率、故障预测指标、正常预测指标等单指标体系以及符合率、综合指数、比数积、故障似然比、正常似然比等综合指标体系，并进一步提出了提高装备状态质量诊断试验效率的平行诊断试验方法和系列诊断试验方法。     

某型直升机主减滑油冷却风扇性能测试及分析

叙述了某型直升机主减滑油冷却风扇性能测试试验情况,并对进口风扇和国产风扇的性能作了分析比较,为该型直升机国产化风扇性能作出了结论,同时为直升机用风扇性能试验总结了经验。     

A Class of TVD Type Combined Numerical Scheme for MHD Equations With a Survey About Numerical Methods in Solar Wind Simulations

It has been believed that three-dimensional, numerical, magnetohydrodynamic (MHD) modelling must play a crucial role in a seamless forecasting system. This system refers to space weather originating on the sun; propagation of disturbances through the solar wind and interplanetary magnetic field (IMF), and thence, transmission into the magnetosphere, ionosphere, and thermosphere. This role comes as no surprise to numerical modelers that participate in the numerical modelling of atmospheric environments as well as the meteorological conditions at Earth. Space scientists have paid great attention to operational numerical space weather prediction models. To this purpose practical progress has been made in the past years. Here first is reviewed the progress of the numerical methods in solar wind modelling. Then, based on our discussion, a new numerical scheme of total variation diminishing (TVD) type for magnetohydrodynamic equations in spherical coordinates is proposed by taking into account convergence, stability and resolution. This new MHD model is established by solving the fluid equations of MHD system with a modified Lax-Friedrichs scheme and the magnetic induction equations with MacCormack II scheme for the purpose of developing a combined scheme of quick convergence as well as of TVD property. To verify the validation of the scheme, the propagation of one-dimensional MHD fast and slow shock problem is discussed with the numerical results conforming to the existing results obtained by the piece-wise parabolic method (PPM). Finally, some conclusions are made. This revised version was published online in August 2006 with corrections to the Cover Date.