Contourlet-based image and video watermarking robust to geometric attacks and compressions

In this paper, we first propose a new blind image watermarking scheme robust to geometric attacks and compressions. The scheme is based on contourlet transform (CT) and principal component analysis (PCA). The scheme uses the principal components of the largest contourlet coefficients of the last directional subband of the cover image to embed the watermark. Meanwhile, with the noise visibility function (NVF), the watermarking strength is adjusted adaptively to preserve the perceptual quality of the image. The watermark can be detected with high accuracy after various possible distortions. The normalized correlation (NC) between the original watermark and the watermark extracted from the distorted watermarked image is used as the robustness evaluation criterion. The simulation results demonstrate that the proposed scheme has good performance in terms of both quality and robustness against a variety of image-processing attacks, such as rotation, scaling and image compressions. Then we extend the scheme to blind video watermarking. The performance of the video watermarking scheme is evaluated against video attacks like rotation, frame averaging, noise additions and video compressions. The introduction of the CT produces robustness against image and video compressions, and the PCA yields resistance to geometric attacks.

     

基于流形学习方法的大数据分析技术在检验检疫行业中应用探讨

在大数据时代背景下,数据分析技术广泛应用于提取海量数据中的有效信息。检验检疫行业形成了以CIQ2000综合业务管理系统为基础,以电子申报、电子监管、电子放行为主要内容的中国电子检验检疫建设格局,积累了大量来源不同、类型不同、时间周期不同、用途不同的结构化和非结构化数据。针对检验检疫业务数据的非线性特征,介绍了基于流形学习方法的大数据分析技术,探讨了其在检验检疫业务中应用的可能性。     

Perceptual quality assessment of stereoscopic images based on local and global visual characteristics

The quality assessment of stereoscopic images has attracted considerable attention and become an important issue in 3D multimedia applications. The 3D image quality assessment (IQA) encounters many challenges and simple extension of the 2D quality metrics to the 3D case is not satisfying. In this paper, we propose a new perceptual quality assessment scheme for stereoscopic 3D images by considering the local and global visual characteristics. The design of this scheme is motivated by studies on the perception of distorted stereoscopic images. To be more specific, after the log-Gabor filter processing, the local amplitude and phase from the left and right views of the reference and distorted 3D images are utilized as features in local quality evaluation. Meanwhile, the global structure changes of the left and right views are also incorporated into the final quality pooling. The overall 3D quality score is obtained by combining the local and global quality indexes together. The effectiveness of the designed metric is verified on publicly available 3D image quality assessment databases. Experimental results show that the proposed scheme exhibits better performance than other related algorithms in terms of consistency with subjective assessment of stereoscopic 3D images.

     

AG—C在高支高密纯棉品种上的应用

为解决普梳纯棉高支高密织物浆纱断头、布机开口不清的问题,设计了以PVA、变性淀粉、AG-C固体聚丙烯浆料为主的配方,对纯棉高密织物使用AG-C前后的上浆效果、织造效果和浆料单耗进行了测试对比,表明AG-C浆料的粘附性好,适量加入可减少PVA的用量,在改善浆膜的柔韧性、提高毛羽贴伏率方面效果显著.     

AG-C在高支高密纯棉品种上的应用

为解决普梳纯棉高支高密织物浆纱断头、布机开口不清的问题,设计了以PVA、变性淀粉、AG-C固体聚丙烯浆料为主的配方,对纯棉高密织物使用AG-C前后的上浆效果、织造效果和浆料单耗进行了测试对比,表明AG-C浆料的粘附性好,适量加入可减少PVA的用量,在改善浆膜的柔韧性、提高毛羽贴伏率方面效果显著.     

试论大学生职业生涯设计若干问题

本文以山东电力高等专科学校为例,结合计量工程系职业规划的问卷调查统计进行分析,揭示职业生涯设计与大学规划、就业问题的关系,旨探讨在帮助大学生选择职业、准备就业、获得职业等方面学校理应采取的工作思路,促使大学生根据自我职业目标做好大学规划。从而锻炼各种能力,提高职业素养,为其毕业后顺利进入职场创造条件。     

如何上好职业院校的《计算机应用基础》

计算机在人们的生活中扮演越来越重要的角色,<计算机应用基础>课也成为职业院校一门必修的公共课程.因此,如何上好职业院校的计算机课程已成为当今职业院校关注的重要问题之一.     

工程机械几种缓冲补油液压装置比较分析

文章主要综合论述了工程机械回转机构中,常用的几种缓冲补油液压装置的特点及适用性,并进行比较分析,为主机厂家选择何种装置提供依据和参考。     

BOPPPS教学模式在药物化学课程教学中的设计与教学效果

针对药物化学课程知识点多、内容零散的情况，我们采用BOPPPS教学模式进行教学，以促进学生主动学习。我们以知识点为微格对教学过程进行设计，并以抗高血压药物卡托普利为例，给出了教学过程6个阶段的具体实施方案。期中和期末对课程整体接受度、课堂表现满意度和教学效果的调查显示， BOPPPS教学模式得到了学生的认可和欢迎。     

The Study of Depolarization Effects due to Rain Media in MM Wave Band by System Identification

We use an equivalent random system for the discrete rain medium. A serial model of computing cross-polar discrimination (XPD) is given by system model with propagation experiment data in Xi'an, China. The calculated results show this method is effective and straightforward.