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1.
在磨粒自动识别系统中,首先对彩色磨粒图像进行预处理,运用图像增强、自适应阈值选取、磨粒的标识和图像二值化方法成功地提取了特征磨粒;然后根据磨粒的识别特征建立描述磨粒形态的特征参数体系,确定了磨粒的三类特征参数(颜色、表面纹理和形状尺寸参数),并对磨粒进行特征量提取创建参数数据库;最后以提取的磨粒特征量为基础,运用灰色定权聚类的方法成功地识别了6种特征磨粒(正常磨粒、球形磨粒、切削磨粒、严重滑动磨粒、Fe2O3磨粒、Fe3O4磨粒).实验表明所提方法切实可行.  相似文献   

2.
IntroductionDuringtheoperationofmachinery ,weardebrisareproducedasaresultofcontactbetweenmovingsurfaces.Thecharacteristicsofweardebris (whichincludeshape ,size,concentration ,surface ,color ,etc .) provideimportantinformationabouttheconditionofmachinery ,in particularthestateofwear .However,thecurrenttechniquesforweardebrisanalysisareusuallytime consumingandcostlyduetotherequirementofanalyst sexpertiseto perform particleinspection ,morphologycharacterizationanddatainterpretation .Thus ,manytec…  相似文献   

3.
磨粒图像的纹理分析及识别   总被引:2,自引:0,他引:2  
以磨粒显微图像分析为应用背景,引入方向测度对磨粒图像表面纹理特征进行描述.该方法对磨粒图像各方向的灰度变化规律进行统计分析,提取了8个纹理特征.然后以提取的纹理特征为输入矢量,利用径向基函数神经网络对磨粒纹理进行分类识别.应用实例表明,方向测度综合反映了磨粒纹理的方向性和粗糙性,可用于磨粒纹理特征的描述;所建立的基于神经网络的磨粒纹理分类模型学习速度快,识别率较高.  相似文献   

4.
The paper presents a study of surface texture character-ization of knitted fabrics during simulated wear based onlaser-scanned profiles.The three-dimensional profilewas obtained by scanning the fabric surface using the la-ser trlangulation technique.The analytical techniquesused to derive quantitative parameters Included statisticalanalysis,fractal analysis,and Fourler analysis.  相似文献   

5.
论述了物体表面形貌的测量在工程上的重要性,指出了目前学术界与工业界所普遍采用的二维表面测量与评定的局限性,进而说明了三维表面测量的重大意义.在此基础上,将三维表面测量仪器,即接触式触针仪器、非接触式光学干涉仪以及原子力显微镜的原理、现状进行了分析比较.同时,对三维表面的评定技术及其三维表面参数,特别是"伯明翰14参数"的发展做了系统的论述.最后,以三维表面形貌测量在人工髋关节柄磨损评定中的应用为例,其结果表明,粗糙表面的髋关节柄和骨水泥之间的磨损为磨粒磨损,而抛光表面的髋关节柄和骨水泥之间的磨损为微动磨损,此为生物医学上进一步降低磨损微粒的产生、提高人工髋关节的寿命提供了重要参考.  相似文献   

6.
7.
针对考古发掘现场堆积在一起的陶瓷碎片难以修复拼接,以及薄壁碎片断裂面特征难以提取的问题,提出了一种综合碎片点云多种特征提取与粗糙集模型进行约简分类的方法。该方法先采用最小半径移动球和三维中心滤波圆弧拟合的方法,分别获取碎片边缘和内部几何特征,再结合颜色纹理及材质等特征要素,通过决策表约简分类为文物碎片重建匹配提供条件。与现有依赖对象单一特征的配对方法不同,本方法在碎片存在磨损甚至缺失等情形下,能将混杂在一起的隶属于多器物薄壁文物碎片进行有效分类配对。  相似文献   

8.
提出了两种图像生成的方法:(1)由图像分割、三维重建和投影生成构成。该方法考虑了图像中各部分表面发射模型的差异,通过将图像各区域向1分成朗伯表面和镜面反射,分别进行三维重建,然后融合两结果,改变光照方向和强度,投影生成新的图像;(2)将Shape from shading和Shape from texture技术融合起来。采用Gabor滤波器将图像中的纹理成分和阴影成分区分开来,再用两种方法各自生成三维立体图像,依据它们的特性在频域融合两个三维图像,然后再改变视角和光照的强度、方向,生成仿真的二维图像。实验表明,由该两种方法恢复出的形状优于传统的估计方法,生成的图像真实感强。  相似文献   

9.
采用离散元颗粒流程序PFC3D(Particle Flow Code)对泥石流启动过程的模型试验进行数值模拟研究.考虑泥石流启动过程中砂土的非饱和特性,在前期研究的基础上对模型进行改进,利用微小颗粒模拟水团,并通过设置黏结模型模拟土颗粒间的基质吸力.将数值模拟结果与室内模型试验进行对比分析,分析得出泥石流的启动表现为后部土体推挤前部土体快速下滑.非饱和状态下,颗粒间的基质吸力提供了一定的土体强度,当渗透力和重力引起的下滑力克服这种颗粒间的黏结力时,土体由非饱和状态逐渐转变为饱和状态,泥石流才会启动.与原有未考虑非饱和特性的数值模拟方法对比,结果表明,使用PFC3D并考虑土体非饱和特性,可以更接近地模拟流滑型泥石流的破坏形态和启动过程.  相似文献   

10.
A new wear-graphy technology was developed, which can simultaneously identify the shape and composition of wear debris, for both metals and non-metals. The fundamental principles of the wear-graphy system and its wear-gram system are discussed here. A method was developed to distribute wear debris on a slide uniformly to reduce overlapping of wear debris while smearing. The composition identification analyzes the wear debris using the scanning electron microscope (SEM) energy spectrum, infrared-thermal imaging and X-ray imaging technology. A wear debris analysis system based on database techniques is demonstrated, and a visible digitized wear-gram is acquired based on the information of wear debris with image collection and processing of the wear debris. The method gives the morphological characteristics of the wear debris, material composition identification of the wear debris, intelligent recognition of the wear debris,and storage and management of wear debris information.  相似文献   

11.
人工关节材料及其表面改性研究进展   总被引:1,自引:0,他引:1  
人工关节是替代病变或损伤关节的植入性假体,除了应满足生物相容性要求外,必须具备足够的抗磨损能力。本文综述了目前使用的不同人工关节材料的性能,以及为提高抗磨损能力而对各种材料进行改性处理的新方法,提出在人工关节表面加工微纳结构来提高其抗磨损性能和生物相容性的新思路。  相似文献   

12.
IntroductionAs the development of production and design of wholegar ment in the infor mation age ,the digitalization of wholegar ment becomes more and more i mportant and necessaryin the field of textile . The digitalization of whole gar mentprovides the convenience and the advantage for the designand the production of whole gar ment .The digitalization of whole gar ment emphasizes on the3D model of it . Digital3D modelingis referred as a processof the recovery of three-di mensional model fro…  相似文献   

13.
The three-dimensional (3D) structure of the wild-type rabbit hemorrhagic disease virus (RHDV) has been determined to a resolution of 3.2 nm by electron cryomicroscopy and computer image reconstruction techniques. The 3D density map exhibits characteristic structural features of a calicivirus: a T=3 icosahedral capsid with 90 arch-like capsomeres at the icosahedral and local 2-fold axes and 32 large surface hollows at the icosahedral 5- and 3-fold axes. This result confirms that the RHDV isolated in China is a member of the Caliciviridae family. A rather continuous capsid shell was found without channels. However, our RHDV structure also reveals some distinct structural characteristics not observed in other caliciviruses, including interconnected capsomeres and the lack of protuberance on the base of each of the surface hollows. Two types of particles were identified with similar outer capsid structure but different density distributions inside the capsid shells, which could not be distinguished by conventional negative staining electron microscopy. As the genomic and subgenomic RNAs are both packaged into particles for RHDV, we suggest that the two types of particles identified correspond to those containing either the genomic or subgenomic RNAs, respectively.  相似文献   

14.
通过对机织物图像的表面形态分析,建立3种基本组织(平纹、斜纹和缎纹)的表面纹理模型,运用傅里叶变换技术得到3种基本组织的频谱模型,并建立表面纹理模型和频谱图模型之间的对应关系,从而为运用图像分析和人工智能技术自动测量织物的结构参数、识别机织物类型奠定理论基础.实验结果证明,这种方法是准确可靠的.  相似文献   

15.
Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle, a cylindrical copper oxide ore sample (φ4.6 mm×5.6 mm) was scanned using high-resolution X-ray computed tomography (HRXCT), a nondestructive imaging technology, at a spatial resolution of 4.85 μm. Combined with three-dimensional (3D) image analysis techniques, the main mineral phases and pore space were segmented and the volume fraction of each phase was calculated. In addition, the mass fraction of each mineral phase was estimated and the result was validated with that obtained using traditional techniques. Furthermore, the pore phase features, including the pore size distribution, pore surface area, pore fractal dimension, pore centerline, and the pore connectivity, were investigated quantitatively. The pore space analysis results indicate that the pore size distribution closely fits a log-normal distribution and that the pore space morphology is complicated, with a large surface area and low connectivity. This study demonstrates that the combination of HRXCT and 3D image analysis is an effective tool for acquiring 3D mineralogical and pore structural data.  相似文献   

16.
轮胎的实时状态受到行驶环境及车辆自身结构的影响,而这些影响可以通过表面纹理的磨损情况得以表征.本文从图像分析着手研究轮胎磨损.考虑到采用单一图像处理方法,会因自身的适用范围而有所局限,甚至有时得不到相应的结果,提出了改进阈值法来提取轮胎磨损纹理特征.该方法包括阈值分割和区域标注两个部分.通过给定初始阈值的迭代优化以及种子填充,图像被分割成具有独立轮廓和结构参数的多单元块.再根据相应的磨损机制进一步分析出磨损原因.实例表明,与Ostu, watershed和主动轮廓线法相比,该方法对不确定的位置有一定的冗余度,分割清晰,速度快,有助于磨损分析.  相似文献   

17.
抛光光学玻璃等硬脆材料时常选用聚氨酯抛光垫,其微观形貌和磨损直接影响抛光精度和效率.本文对不同抛光时长下聚氨酯抛光垫微观形貌和磨损行为及其对材料去除率和表面粗糙度的影响进行了实验研究.结果表明:当主轴转速为8 000 r/min,进给速度为0.015 0 mm/s,轴向超声振幅为5μm时,材料去除率和表面粗糙度分别为0.977μm/min和153.67 nm.聚氨酯抛光垫在30 min内磨损量较小,随着抛光时长的增加,抛光垫表面孔隙逐渐被磨粒和玻璃碎屑填充,破坏抛光垫表面的疏松多孔结构,导致抛光垫表面硬化,失去弹性.同时,侵入抛光垫表面的磨粒会阻止抛光接触区域内的磨粒更新,导致抛光质量降低.  相似文献   

18.
基于二维连续小波变换的织物疵点检测   总被引:1,自引:0,他引:1  
同正常织物纹理比较,疵点区域由于其纹理不规则及变形而导致不同的局部纹理特征。利用二维连续小波特征,能在时域和频域上对织物图像同时实现任意尺度和旋转角度的变换。通过纹理模型和频谱分析,确定出最优的变换尺度和旋转角度,并由预先确定的全局阈值从小波变换系数的模中进行疵点的分割。实际疵点的检测结果表明该方法是可行的。  相似文献   

19.
针对目前计算机生成图像鉴别算法在对图像纹理特征进行鉴别时精度较差的问题, 提出一种基于长期控制计划(LTCP)特征的计算机生成图像鉴别算法. 首先将彩色图像变换到颜色模型中, 对图像进行下采样, 获得较高尺度的纹理信息; 然后采用基于LTCP特征和共生矩阵的计算机生成图像盲鉴别算法, 对不同尺度的纹理图像LTCP特征及相邻像素一致性共生矩阵特征进行采集; 最后通过判别分类器对LTCP特征及相邻像素一致性共生矩阵特征实施分类预测, 根据分类预测结果实现计算机生成图像的鉴别. 实验结果证明, 该算法在计算机上生成的图像特征维度较低, 鉴别率和精度较高, 能实现计算机生成图像的准确鉴别.  相似文献   

20.
应用计算机图像纹理分析的理论与方法探讨了稀土氧化物 (La2 O3 )对Ni/α Mg2 Al4 SiO5O18催化剂表面结构的影响 .研究表明 ,空间灰度值共生矩阵 (SGLCM)法所抽取的纹理熵和纹理能特征是催化剂表面镍的分散状态和稳定性的有效度量 ,将所获得的信息与催化剂表面的镍晶粒度及活性相关联 ,均取得较好的一致性 ,说明计算机图像纹理分析是催化剂设计和结构分析的新途径 .  相似文献   

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