基于自适应窗口固定及传播的 多尺度纹理图像分割

 本文提出一种基于自适应窗口固定及传播的多尺度纹理图像分割方法,在小波域隐马尔科夫树模型(WHMT)的初始分割基础上,根据分割粗尺度上的区域一致性好,细尺度上的边缘准确的特点,利用上下尺度像素之间以及本层邻域像素的马尔科夫性,标记出图像的一致性区域和边缘区域,将一致性区域固定,类标直接下传到下一尺度,边缘区域则利用邻域信息确定出上文权值背景传播到下一尺度,与下尺度一起共同指导图像分割,从而很好的保持了区域均匀性和边缘准确性.同时根据纹理图像区域聚集性的特性,利用基于多项式展开和置信区间交叉(LPA_-ICI)方法找出各类区域聚集的物理位置中心,融入上下文权值背景中,使得指导分割策略能够更好的进行.实验表明,对于合成纹理图像来说,本文提出的多尺度融合算法在均匀区域内部及区域边界都大为改善,而且无须进行参数的训练,使算法快速的完成.     

表面织构对红光LED发光的影响

运用蒙特卡罗法模拟二维红光LED表面织构对LED光提取效率的影响.模拟了不同形状的表面织构对应的光强变化率.选取刻蚀深度为4μm、腐蚀宽度为2μm、倾角为40°、周期为2μm的表面图形对LED进行粗化实验.结果显示,引入表面织构后光强比常规LED提高了20.56%;并对模拟结果与实验结果进行了分析,结果表明引入表面织构可以有效地提高LED的光提取效率.     

沥青路面结构光条质心定位算法

将基于结构光的激光三角法应用于沥青路面构造深度检测,并提出适合该场合的结构光条质心定位算法。根据激光束宽度较窄且光强较大的特点,对采集图像进行固定阈值和平均阈值相结合的滤波处理,同时根据粗糙沥青路面存在漫反射的特性,利用有效光斑窗口长度最大化的干扰消除方法去除孤点噪声,最后由亚像素级的重心法实现质心定位。实验数据表明,本文方法测量路面构造深度的精度可达到0.1mm。相比于目前主流的基于激光测距的路面构造深度检测,可实现由线到面的跨越。     

草地的红外纹理建模与真实感绘制方法

纹理是使图像具有视觉真实感的重要因素,红外纹理生成是场景红外成像仿真的重要组成部分,也是真实感场景仿真的迫切需求。以在图像平面直接生成具有真实感的景物红外纹理图像为目标,提出了一种草地的红外纹理建模与真实感绘制方法,从模拟组分温度分布和空间结构形态两方面开展研究。首先,考虑土壤-植被-大气间的热交换过程,建立红外辐射的耦合求解模型;其次,构建各组分的空间分布模式;最后,将已经求解的红外辐射数据映射到图像空间,生成具有真实感的红外纹理图像。对近距离或放大状态下草地红外纹理的视觉效果进行了模拟,理论分析和仿真结果表明:所提出的红外纹理模拟方法具有一定的合理性和有效性。     

基于灰度-梯度共生矩阵的车轮踏面缺陷聚类分析北大核心CSCD

车轮作为列车走行部的关键部件之一,其踏面产生缺陷后会直接影响到列车的运行安全。为了能够在检测时准确识别车轮踏面缺陷不同类型,提出一种基于灰度-梯度共生矩阵的纹理特征提取方法,对踏面图像的灰度和梯度特征分析之后,根据灰度-梯度共生矩阵提取踏面图像纹理特征矢量,再结合K-均值(K-means)聚类优化算法对踏面缺陷特征量进行聚类,从而将踏面缺陷类型进行分类,并将分类结果用可视化数据显示。实验结果表明,采用上述所提方法,对车轮踏面缺陷不同类型的分类识别精度达96%以上。     

基于小波散射卷积网络的纹理分割方法

针对物体的纹理特征进行图像分割的问题,提出一种基于小波散射卷积网络的纹理分割方法.首先利用小波散射卷积网络提取每个子图像块的散射能量分布特征;然后采用全局阈值处理的Ostu方法,对各层级散射能量特征值矩阵进行分类,得到粗分割结果;最后利用形态学方法消除粗分割中的虚假点,得到细分割结果,从而实现了无监督的纹理分割.实验结果表明,该方法用于纹理图像分割及车牌定位都能获得很好的效果.     

视景仿真技术应用研究

概述视景仿真系统的软件系统和硬件系统基本组成,分析研究了软件系统中的一些关键技术问题,包括利用MFC实现分布式仿真、创建基于MFC的Vega SDI仿真程序、OpenGL回调函数、纹理映射建模等．提出了视景仿真的建模流程．采用了Vega渲染环境,用于实时视觉模拟的定义和场景的描述,选用编程工具Visual C ,进行视景仿真的调试．扩展了视景仿真技术在军事研究领域的应用,将对提高未来武器装备的性能和研制效率产生一定的影响．     

自动监视和告警系统中红外弱小目标的识别

红外弱小目标识别一直是自动监视和告警系统中的一项关键技术。成像跟踪识别系统的算法研究需要分析特定应用环境中的背景和目标特点,本文第一部分对此进行了分析。接下来,在对应用环境进行分析的基础上,对远距离红外小目标的探测、识别和跟踪算法进行了介绍。最后,针对视频环境下的红外跟踪,介绍了为提高跟踪稳定性而进行的一系列实验及其原理装置。     

The microstructure,mechanical stress,texture, and electromigration behavior of Al-Pd alloys

As the minimum feature size of interconnect lines decreases below 0.5 urn, the need to control the line microstructure becomes increasingly important. The alloy content, deposition process, fabrication method, and thermal history all determine the microstructure of an interconnect, which, in turn, affects its performance and reliability. The motivation for this work was to characterize the microstructure of various sputtered Al-Pd alloys (Al-0.3wt.%Pd, Al-2Cu-0.3Pd, and Al-0.3Nb-0.3Pd) vs sputtered Al-Cu control samples (Al-0.5Cu and Al-2Cu) and to assess the role of grain size, mechanical stress, and crystallographic texture on the electromigration behavior of submicrometer wide lines. The grain size, mechanical stress, and texture of blanket films were measured as a function of annealing. The as-deposited film stress was tensile and followed a similar stress history on heating for all of the films; on cooling, however, significant differences were observed between the Al-Pd and Al-Cu films in the shape of their stress-temperature-curves. A strong (111) crystallographic texture was typically found for Al-Cu films deposited on SiO₂. A stronger (111) texture resulted when Al-Cu was deposited on 25 nm titanium. Al-0.3Pd films, however, exhibited either a weak (111) or (220) texture when deposited on SiO₂, which reverted to a strong (111) texture when deposited on 25 nm titanium. The electromigration lifetimes of passivated, ≈0.7 μm wide lines at 250°C and 2.5 × 10⁶ A/cm² for both single and multi-level samples (separated with W studs) are reported. The electromigration behavior of Al-0.3Pd was found to be less dependent on film microstructure than on the annealing atmosphere used, i.e. forming gas (90% N₂-10%H₂) annealed Al-0.3Pd films were superior to all of the alloys investigated, while annealing in only N₂ resulted in poor lifetimes.     

Texture and microstructure of thin copper films

Microstructure is an important factor influencing the reliability of thin film interconnects. The microstructure of copper films is of particular interest because of its use in numerous electronic applications. Pole figure x-ray diffraction and transmission electron microcopy were conducted on copper films deposited by several techniques: sputtering, partially ionized beam deposition, chemical vapor deposition, evaporation, and electroplating. Quantitative texture data are determined from fiber texture plots. A typical copper film consists of three texture components: (111), (200), and random. (220) and (511) texture components are possible under some deposition conditions. Compared to aluminum films, the fraction of the random texture component and the distribution of the (hkl) components in copper films are relatively large. Bimodal grain size distributions are observed in some films.