双探针原子力显微镜针尖对准方法研究

双探针对顶测量可以有效地消除传统原子力显微镜（AFM）的探针形状对关键尺寸（CD）测量的影响。测量前需要将两个探针针尖（A和B）接触到一起作为测量零点,为实现双探针纳米级对准,提出一种渐进式平面扫描方法。首先,通过视觉图像引导两个探针对准到1μm以内。然后,两个探针继续接近,同时探针A在YOZ平面内对探针B扫描成像,并逐步缩小扫描范围和扫描步进,得到其针尖的纳米级坐标（Y_B,Z_B）。最后,将探针A在Y和Z方向分别移动至Y_B和Z_B,在X方向继续接近探针B直至两探针接触。实验证明,该方法可有效地实现双探针对准,且对准精度为10 nm。     

100nm线宽的掩模硅片自动对准算法

对100nm线宽尺寸建立了掩模硅片自动对准数学模型,应用于同轴加离轴对准系统的硅片模型、掩模模型以及工件台模型中,该对准算法模型有一定可行性,能很好地满足100nm线宽对准精度的要求。     

光刻对准技术研究进展

回顾了光刻对准技术的发展功能,对各种对准方法的原理和特点进行了分析和评价,介绍了几种典型主流光刻对准系统结构形式,并对光刻对准技术前景进行了描述与展望。     

Unprecedented Dual Alignment Mode and Freedericksz Transition in Planar Nematic Liquid Crystal Cells Doped with Gold Nanoclusters

We demonstrate that alkylthiol‐capped gold nanoclusters doped into nematic liquid crystals (N‐LCs) with positive dielectric anisotropy give rise to an unprecedented dual alignment mode and electro‐optical response, which has a potential impact on current liquid crystal (LC) display technologies and N‐LC optical‐biosensor design. By fine‐tuning experimental conditions (temperature, electric field, and alignment), N‐LCs doped with gold nanoclusters can be aligned and electrically reoriented either like N‐LCs with a positive dielectric anisotropy in a planar cell or, alternatively, as N‐LCs with a negative dielectric anisotropy in a homeotropic cell, both at lower threshold voltages than the pure N‐LC.     

某内燃机机体损坏后的修理

某内燃机机体遭受断裂连杆撞击,缸套冷却水腔下密封内表面和滑油喷嘴安装法兰表面严重破损、变形;主轴瓦孔内径和中心线直线度超差。采用铸铁焊工艺局部焊补破损位置后加工至标准尺寸,然后采用电刷镀工艺修复主轴瓦孔至标准尺寸,用激光自准仪检测主轴瓦孔中心线直线度达到标准要求。     

核正交判别局部正切空间对齐算法

针对现有的局部正切空间算法中存在的问题,文中提出一种基于核变换的特征提取方法——核正交判别局部正切空间对齐算法(KOTSDA)。该算法首先利用核方法将人脸图像投影到一个高维非线性空间,提取其非线性信息;然后在目标函数中利用正切空间判别分析算法在保持样本的类内局部几何结构的同时最大化类间差异;最后添加正交约束,得到核正交判别局部正切空间对齐算法。该算法不需要经过PCA降维,有效避免判别信息的丢失,在ORL和Yale人脸库上的实验验证算法有效性。     

Nematic liquid crystal alignment on the ion beam-exposed ZnO film

This paper investigates the nematic liquid crystal (NLC) alignment on ion beam-exposed zinc oxide (ZnO) films. The ZnO films are deposited by a radio frequency magnetron sputtering. During the deposition of ZnO film, we supplied sufficient oxygen gas for high resistivity and transmittance. The deposited films show a high transmittance of over 90% and high resistivity of over 10¹⁰ Ω cm. The ZnO films show a high deposition rate of 26.7 Å/min. Images obtained via scanning electron microscopy of the ZnO film surfaces, before and after the ion beam exposure, show that groove patterns are formed being to be parallel to the ion beam exposure direction. LC cells are fabricated with the ion beam-exposed ZnO films. The NLC molecules align parallel to the ion beam exposure direction. The electro-optic and response characteristics of fabricated cells show the possibility of application to liquid crystal displays.     

一种分层聚类方法在音乐检索中的应用

针对基于内容的音乐检索在查准率和查找效率上不能同时达到理想效果的情况,提出一种基于单侧连续匹配的分层聚类算法,即在匹配之前对音乐特征进行聚类。根据相似度值对特征空间进行分类,形成不同簇类,并对簇中心进行标记,再对聚类后的数据库进行精确匹配。实验表明,该方法不仅提高了音乐检索的效率,而且保证了较高的检索准确率。     

海岸吊拖车对位系统简介

针对港口货车对位存在的实际问题,我们开发出了基于光电技术和PLC的拖车对位系统。本文主要介绍了拖车对位系统的原理和功能的实现,通过在现场的运行实践表明该系统能显著提高港口的工作效率。     

Musculoskeletal kinematics during voluntary head tracking movements in primate

In this study we examined connections between vertebral motion and patterns of muscle activation during voluntary head tracking movements. A Rhesus(Macaca mulatto) monkey was trained to produce sinusoidal tracking movements of the head in the sagittal plane while seated. Radio-opaque markers were placed in the cervical vertebrae, and intramuscular patch electrodes were implanted to record from eight neck muscles. Videofluoroscopic images of cervical vertebral motion, and EMG (electromyographic) responses were simultaneously recorded. Experimental results demonstrated that head and vertebrae moved synchronously and that motion occurred primarily at skull-C₁, C₆-C₇ and C₇-T₁. Our findings illustrate that although the biomechanical constraints of each species may limit the number of solutions available, it is the task requirements that appear to govern CNS (central nervous system) selection of movement behaviors.