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21.
Mingwei Wang  Xiaolei Wang  Zhilei Li 《Optik》2010,121(24):2254-2258
In this paper, an 8-neighborhood-based Generalized Hough Transform (ENGHT) for the recognition of multibreak patterns is proposed, which is different from the Generalized Hough Transform (GHT). The difference between ENGHT and GHT appears in the process for Reference-table (R-table) configuration and for pattern recognition. The theoretic and experimental results show that ENGHT can be employed in the recognition of multibreak patterns with a high precision and a high recognition speed, and reduce the difficulty during the recognition that arose from the broken patterns to be processed by the conventional GHT. ENGHT can be employed in pattern recognition, especially in the multibreak pattern recognition.  相似文献   
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基于CCD的物体测量平台,首先对物体图像进行预处理,继而利用Canny算子提取物体边缘,再通过本文改进的Hough变换实现对被测物体边界直线检测和重构,最后通过多项式插值算法实现物体像素尺寸到物体实际尺寸的转换.实验证明,此方法能够实现无接触式物体尺寸较高精度的测量.  相似文献   
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The aim of the paper is to apply some inductive learning method from examples (which gives explicit decision rules of “if-then” type) to forecast the voting behaviour of individual members of the Polish Parliament. Results obtained are both interesting and promising. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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讨论了Hough变换及其与相关计算的关系 ,提出了基于非相干光相关器的 ,以直线阵列作模板 ,以线光源阵列为照明光源的Houhg变换光学系统。并给出了计算机模拟此系统运算的结果。  相似文献   
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针对倒装焊中常用的十字架对准标志的几何特征,采用形态学边缘检测算法提取图像边缘,通过将简化的Hough变换和最小二乘相结合的直线提取方法,提取出较为精确的边缘直线,实现了一种提取十字架标志的四条长边缘直线的图像处理算法。实验结果表明,该算法与相关算法相比具有更快的对准速度和更高的对准精度,且对有局部残缺的图像不敏感。  相似文献   
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In particle tracking velocimetry, the necessary information is the 3D location of a given particle in space. This information can be obtained by examining the real image or by analyzing the interference fringe recorded on a digital camera. In this work, we measure the three-dimensional position of spherical particles by calculating the Central Spot Size of the interference pattern of a particle diffraction image. The Central Spot Size is obtained by combining the Continuous Wavelet transform and circle Hough transform. The Continuous Wavelet transform allow us in only one step enhanced quality of particle images and sets a threshold to select properly places where a Central Spot Size appear in order to determine its size via the Hough transform. The size and centroid of the Central Spot Size render z and x-y position of a particle image, respectively. The Central Spot Size is related to a criterion of a simplified theory given by the Fraunhofer theory in order to obtain z particle position. Our approach has been applied to simulated and experimental particle images. Simulated particle images show good agreement between actual and calculated Central Spot Size. An average relative error of 0.5% and 1.12% for x-y and z directions, respectively, was found in the analysis. Our experimental particle images were obtained from particle motion inside a channel. The quality of the particle images determines the accuracy of the calculation of the Central Spot Size of a particle image.  相似文献   
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The voting system of the Legislative Council of Hong Kong (Legco) is sometimes unicameral and sometimes bicameral, depending on whether the bill is proposed by the Hong Kong government. Therefore, although without any representative within Legco, the Hong Kong government has certain degree of legislative power – as if there is a virtual representative of the Hong Kong government within the Legco. By introducing such a virtual representative of the Hong Kong government, we show that Legco is a three-dimensional voting system. We also calculate two power indices of the Hong Kong government through this virtual representative and consider the C-dimension and the W-dimension of Legco. Finally, some implications of this Legco model to the current constitutional reform in Hong Kong will be given.  相似文献   
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