基于PCNN的图像纹理平滑度的特征提取

脉冲耦合神经网络(PCNN)是基于猫视觉原理构建的一种简化的神经网络模型，它适合基于视觉内容的特征提取。该文在改进模型的基础上运用PCNN神经元的点火捕获特性提取出了一种度量图像纹理平滑程度的特征量——捕获率；同时结合PCNN与傅立叶功率谱得到图像的低频能量与图像总能量的比例关系，作为度量图像纹理平滑程度的另一个特征量——低频能量比。最后通过图像检索实验验证了这两个特征量的有效性。     

A sub-pixel stereo matching algorithm and its applications in fabric imaging

In this paper, we describe a sub-pixel stereo matching algorithm where disparities are iteratively refined within a regularization framework. We choose normalized cross-correlation as the matching metric, and perform disparity refinement based on correlation gradients, which is distinguished from intensity gradient-based methods. We propose a discontinuity-preserving regularization technique which utilizes local coherence in the disparity space image, instead of estimating discontinuities in the intensity images. A concise numerical solution is derived by parameterizing the disparity space with dense bicubic B-splines. Experimental results show that the proposed algorithm performs better than correlation fitting methods without regularization. The algorithm has been implemented for applications in fabric imaging. We have shown its potentials in wrinkle evaluation, drape measurement, and pilling assessment.     

高速数控机床平滑路径规划分析

高速数控机床切削速度大于60 m/min,加速度大于2g,对于小曲率及不连续切线加工,易导致冲击尖峰,产生机械振动,降低切削质量,缩短设备寿命。目前,通过路径平滑技术可消除刀具路径的不连续性,但该技术仅限于线性刀具路径。提出基于双回旋曲线倒角的路径平滑方法,该方法可将任意直线、弧组成路径转换为曲率连续路径,通过路径的弧长参数化,简化插值。通过数控激光切削机床测试可知,平滑圆角可在圆弧与圆弧之间或圆弧与直线之间拟合。与贝塞尔曲线圆角比较分析可知,该方法提高了进给速度,缩短了循环时间,且所得曲率轮廓更平滑。     

基于傅里叶变换的图像素描效果生成算法

首先将真彩色图像转换为灰度图像,通过傅里叶正变换后将所有像素点的幅值设定为一常数,进行傅里叶逆变换,得到像素点的新灰度值;然后将每点灰度值倒置求反,再对图像进行锐化和平滑等处理来实现图像的素描效果。实验结果证明：该算法快速有效,生成的素描图像既能进行图像识别,提高图像质量,又可以达到美术和艺术效果,具有较高的理论和应用价值。     

Similarity relation matrix-based color edge detection

A novel edge detection algorithm for color images was described in this paper. In the proposed method, smoothness of each pixel in color image is firstly calculated by means of similarity relation matrix and is normalized to maximum gray level. In other words, color image in three-dimensional color spaces is mapped into one dimension. Accordingly the edges are performed in such a way that pixels lower than thresholds are assigned to be edge. Thus with proposed method, edge pixels in a color image are detected simultaneously without any complex calculations such as gradient, Laplace and statistical calculations.     

结合包光滑性的半监督多示例核学习方法

以往半监督多示例学习算法常把未标记包分解为示例集合,使用传统的半监督单示例学习算法确定这些示例的潜在标记以对它们进行利用。但该类方法认为多示例样本的分类与其概率密度分布紧密相关,且并未考虑包结构对包分类标记的影响。提出一种基于包层次的半监督多示例核学习方法,直接利用未标记包进行半监督学习器的训练。首先通过对示例空间聚类把包转换为概念向量表示形式,然后计算概念向量之间的海明距离,在此基础上计算描述包光滑性的图拉普拉斯矩阵,进而计算包层次的半监督核,最后在多示例学习标准数据集和图像数据集上测试本算法。测试表明本算法有明显的改进效果。     

振荡压实技术在桥面铺装施工中的应用

阐述了振荡压路机压实的工作原理,结合石家庄市环城公路桥面沥青混合料铺装施工振荡压路机的实际应用,对采集的沥青路面的压实度增长率、横向压实度的均匀度和平整度等技术参数进行了分析.振荡压路机实际应用效果表明,振荡压实技术在桥梁结构免受振动冲击影响的前提下,能够快速提高沥青混合料压实度的增长率,充分保证沥青混合料的压实度,有效地提高了桥面的平整度.