纳米材料表征用扫描探针显微镜

纳米材料研究中不可缺少的分析工具是扫描探针显微镜，本文将介绍这种显微镜的简史、种类、工作原理、最新发展及应用情况。     

多目标跟踪（MTT）技术的发展

本文介绍了多目标跟踪（ＭＴＴ）技术的起源，发展概况和应用前景，还介绍了ＭＴＴ中主要技术的组成和现状。     

边界扫描—一种新的测试技术

本文在简要介绍传统测试方法及其存在问题的基础上，阐述了一种新的测试技术──边界扫描测试技术，并对测试技术的发展趋势作了初步探讨。     

波轮零件的逆向设计

逆向工程是由三坐标测量机或三维激光扫描仪对已有的样品或模型进行准确、高速的扫描，得到其三维轮廓数据，配合反求软件进行修改和再设计。本文详细介绍波轮零件的逆向设计过程。     

基于实波束扫描的相控阵雷达前视成像

实现机载或弹载雷达正前方目标区域高分辨力成像对提高着陆安全性或制导精度有着重要的意义,基于相控阵雷达(PAR)工作原理,建立前视扫描过程中的回波信号模型,对目前广泛研究的解卷积前视成像方法进行了深入分析,指出其未能有效提高方位分辨力的原因,并在此基础上提出了一种基于压缩感知理论的扫描雷达前视成像方法。该方法通过对大时宽带宽积信号的脉冲压缩获得径向高分辨,并基于场景中的强散射中心分布具有稀疏性(可压缩)这一事实,利用压缩感知最优化方法获得高的方位分辨力,仿真结果证明了所提方法的有效性,分析了基于压缩感知前视成像方法的性能。该方法同样适用于机械扫描雷达的前视成像。     

Damage characteristics and constitutive modeling of the 2D C/Si C composite: Part I – Experiment and analysis

This paper reports an experimental investigation on the macroscopic mechanical behaviors and damage mechanisms of the plain-woven(2D) C/Si C composite under in-plane on- and offaxis loading conditions. Specimens with 15, 30, and 45 off-axis angles were prepared and tested under monotonic and incremental cyclic tension and compression loads. The obtained results were compared with those of uniaxial tension, compression, and shear specimens. The relationships between the damage modes and the stress state were analyzed based on scanning electronic microscopy(SEM) observations and acoustic emission(AE) data. The test results reveal the remarkable axial anisotropy and unilateral behavior of the material. The off-axis tension test results show that the material is fiber-dominant and the evolution rate of damage and inelastic strain is accelerated under the corresponding combined biaxial tension and shear loads. Due to the damage impediment effect of compression stress, compression specimens show higher mechanical properties and lower damage evolution rates than tension specimens with the same off-axis angle. Under cyclic tension–compression loadings, both on-axis and off-axis specimens exhibit progressive damage deactivation behaviors in the compression range, but with different deactivation rates.     

三维立体相位扫描测量技术在发动机孔探中的应用

介绍了工业视频内窥镜测量技术的发展历程及民航孔探工作的常用测量方式,并从工作质量、工作效率以及安全角度考虑．推荐使用高精度、单视窗的三维测量技术。