用于车身材料力学试验的非接触测量系统开发

基于静、动态试验平台分别搭建了相应的非接触测量系统,采用数字图像相关法(DICM)提取变形信息,实施了车身材料和点焊构件试验的变形测量。静态试验的引伸计和非接触变形测量对比以及LY12cz铝合金材料的静动态试验对比显示,非接触测量是准确可靠的。与传统变形测量方法相比,非接触测量在全场变形获取、平台兼容和结果可靠性等方面都表现出优势。     

基于小波和SVR的红外弱小目标检测方法

在分析红外图像弱小目标特征和背景特征的基础上,提出了基于小波变换和支持向量回归（SVR）的自适应滤波的检测方法．该方法首先采用小波变换抑制大部分背景杂波;然后用基于SVR的自适应滤波器（SVRBAF）对高频小波系数进行处理,大大提高了图像的信噪比;最后,基于目标的连续性和运动轨迹的一致性,采用流水线结构的序列处理方法进一步提高检测性能．仿真结果表明：该方法可显著提高红外目标的检测概率,实现较远距离弱小目标的检测．     

Hepatic CT image query based on threshold-based classification scheme with gabor features

Hepatic computed tomography(CT) images with Gabor function were analyzed.Then a threshold-based classification scheme was proposed using Gabor features and proceeded with the retrieval of the hepatic CT images.In our experiments, a batch of hepatic CT images containing several types of CT findings was used and compared with the Zhao's image classification scheme, support vector machines(SVM) scheme and threshold-based scheme.     

Image series segmentation and improved MC algorithm

A semiautomatic segmentation method based on active contour is proposed for computed tomography （CT） image series. First, to get initial contour, one image slice was segmented exactly by C-V method based on Mumford-Shah model. Next, the computer will segment the nearby slice automatically using the snake model one by one. During segmenting of image slices, former slice boundary, as next slice initial contour, may cross over next slice real boundary and never return to right position. To avoid contour skipping over, the distance variance between two slices is evaluated by an threshold, which decides whether to initiate again. Moreover, a new improved marching cubes （MC） algorithm based on 2D images series segmentation boundary is given for 3D image reconstruction. Compared with the standard method, the proposed algorithm reduces detecting time and needs less storing memory. The effectiveness and capabilities of the algorithm were illustrated by ,experimental results.     

图式与语篇回指

目前国内流行的回指理论无法解释语篇回指确认中一些复杂的情况,本文介绍并使用了图式理论来进行分析解释。我们发现作为人脑长期记忆中经验的储存方式,图式可以较好地解释复杂的回指现象。     

引入图式理论提高EFL阅读能力的对策

在阅读理解中,文化背景知识起着举足轻重的作用。交互式阅读模式是建立在图式理论基础上对信息加工两种模式(自上而下与自下而上)的综合。文章以认知心理学的视角,从影响学生阅读能力的非语言因素--背景知识(图式)出发,运用图式理论,结合英语阅读学习中存在的实际问题,针对现有的问题提出一些提高EFL阅读能力的对策。     

隧道检测裂缝的图像处理研究

裂缝是隧道衬砌最常见的病害之一,基于近几年快速发展的工程检测系统与图像处理算法的研究,提出基于CCD相机的衬砌裂缝检测系统来采集裂缝图像。通过比较均值滤波、中值滤波、维纳滤波、自适应中值滤波和加权邻域滤波比较,选择自适应中值滤波进行图像增强。结合直方图阈值分割法、Otsu最大类间方差阈值和局部阈值分割法,对增强后图像进行二值化处理比较,Otsu法较好地保留了裂缝的边缘信息,证明了该算法的有效性,为后续裂缝信息的提取奠定了基础。     

一种基于遗传算法和小波分解的刚性图像配准方法

为了实现快速、高精度的自动图像配准,提出了基于遗传算法和小波分解的图像配准方法。此方法在小波分解的基础上,以互信息为相似性测度利用遗传算法为搜索算法对图像进行一次配准,然后以特定步长在小范围内对配准参数进行修正,对图像进行二次配准。该方法实验结果表明该方法具有较快的速度且显著的改善了配准精度。     

小波变换和梯度对多聚焦图像的多分辨率融合

提出一种结合Roberts梯度和小波变换的图像融合方法.该方法对低频分量采用加权平均,对高频分量采用结合梯度平均值的规则.实验结果表明,该方法能够提高多分辨率图像融合方法的效果.     

A semi-fragile wavelet transform watermarking scheme for content authentication of images

A novel semi-fragile watermarking scheme for the content authentication of images using wavelet transform (WT) is presented in this paper. It is tolerant to the embedded wavelet image compression methods based on WT such as embedded zerotree wavelet (EZW), set partitioning in hierarchical trees (SPIHT) and embedded block coding with optimized truncation (EBCOT) in JPEG2000 to a pre-determined bit-plane, but is sensitive to all other malicious attacks. The image features are generated from the lowest-frequency (LF) subband of the original image as the embedded watermark. The watermark is embedded into the pre-determined bit-plane by adjusting the corresponding values in the given subband. In the process of watermarking authentication, we compare the image features generated from the LF subband of the received image with the embedded watermarking information (the image features of the original image) extracted from the pre-determined bit-plane in the given subband of the received image to decide whether the image is attacked maliciously or processed acceptably (the embedded wavelet compression). The most important advantage of our watermarking scheme is that the watermark information can be extracted from the watermarked image when detecting watermark, so the received image authentication needs no information about the original image or watermark. Experimental results prove the effectiveness of our proposed watermarking scheme.