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新形势下职业教育对教师的要求提出更新的内涵,例如更强调适度超前的专业知识,更强调实际应用技能,更强调现代媒体的掌握能力,但更重要的还是教师道德人格力量的塑造,这是至关重要。正因为如此,广大高职教师的道德风貌如何,已经成为一个关系到整个社会精神面貌的大问题。如果每个教师都具有高尚的道德,就会对全社会的思想道德建设产生巨大的推动力。 相似文献
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以图像和文本为掩护的隐蔽通信及其对抗技术 总被引：1，自引：0，他引：1
1IntroductionSince the early1990s,information hiding has be-come a hot topic attracting much attention from re-searchers in various fields including signal processing,cryptography and computer science,developers andsuppliers of multi media contents,and professionalsand other personnel who are concerned with informa-tion security[1].Two major areas are of the most inter-ests:digital watermarking and steganography.The purpose of digital watermarkingis to protect in-tellectual property rights of … 相似文献
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In this work, image feature vectors are formed for blocks containing sufficient information, which are selected using a singular-value criterion. When the ratio between the first two SVs are below a given threshold, the block is considered informative. A total of 12 features including statistics of brightness, color components and texture measures are used to form intermediate vectors. Principal component analysis is then performed to reduce the dimension to 6 to give the final feature vectors. Relevance of the constructed feature vectors is demonstrated by experiments in which k-means clustering is used to group the vectors hence the blocks. Blocks falling into the same group show similar visual appearances. 相似文献
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通过对天津体育学院高职体育专业2010届专科毕业生的工作目标、教学安排以及就业去向等方面的期望进行定量和定性分析,提出就业工作除了学校和家庭的重视外,关键还在学生自身。学生综合素质的高低对其就业有深刻的影响,因此,培养高水平、复合型的人才,增强学生就业竞争力,是提高学生就业率的根本保证。 相似文献
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A color-intensity feature extraction method is proposed aimed at supplementing conventional image hashing algorithms that only consider intensity of the image. An image is mapped to a set of blocks represented by their dominant colors and average intensities. The dominant color is defined by hue and saturation with the hue value adjusted to make the principal colors more uniformly distributed. The average intensity is extracted from the Y component in the YCbCr space. By quantizing the color and intensity components, a feature vector is formed in a cylindrical coordinate system for each image block, which may be used to generate an intermediate hash. Euclidean distance is modified and a similarity metric introduced to measure the degree of similarity between images in terms of the color-intensity features. This is used to validate effectiveness of the proposed feature vector. Experiments show that the color-intensity feature is robust to normal image processing while sensitive to malicious alteration, in particular, color modification. 相似文献
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利用边缘像素负载信息的二值图像密写 总被引：4，自引：0，他引：4
We present a novel scheme for embedding secret data into a binary image without introducing noticeable artifacts. Unlike some block-based methods, the proposed scheme encodes the secret bits directly into boundary pixels by checking each pixel of the cover image in a pseudo-random order for embedding eligibility. A set of rules ensures correct identification of data-carrying pixels in blind extraction. The proposed scheme does not generate isolated dots, and can incorporate various coding methods such as matrix encoding to further improve the embedding performance. It is shown that up to one fourth of the boundary pixels may be used to carry secret data. Experimental results indicate that the method can achieve good visual quality with fairly large data capacity. 相似文献
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稳健图像Hash研究进展 总被引：3，自引：0，他引：3
The easy generation, storage, transmission and reproduction of digital images have caused serious abuse and security problems. Assurance of the rightful ownership, integrity, and authenticity is a major concern to the academia as well as the industry. On the other hand, efficient search of the huge amount of images has become a great challenge. Image hashing is a technique suitable for use in image authentication and content based image retrieval （CBIR）. In this article, we review some representative image hashing techniques proposed in the recent years, with emphases on how to meet the conflicting requirements of perceptual robustness and security. Following a brief introduction to some earlier methods, we focus on a typical two-stage structure and some geometric-distortion resilient techniques. We then introduce two image hashing approaches developed in our own research, and reveal security problems in some existing methods due to the absence of secret keys in certain stage of the image feature extraction, or availability of a large quantity of images, keys, or the hash function to the adversary. More research efforts are needed in developing truly robust and secure image hashing techniques. 相似文献
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武术技击类课程是公安警察院校开展的警察技能与战术基础的重要内容,兼有提高警察职业技能和警察体育发展的双重任务。采用问卷调查法等,对全国15所公安警察院校的武术技击类课程设置进行调查分析,研究认为:公安院校武术技击类课程存在教学内容的衔接性不强,教学课时不足,教学和实践不能有效结合,过于重视动作规格,教师力量薄弱一定程度上制约武术技击类课程实施效果等问题;提出了立体构建武术技击类课程教学体系,教学资源系统整合,教学内容优化组合重视实践教学,增加情景实战教学环节等相应的改革措施。 相似文献
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Block-wise fragile watermarks can be used to reveal maliciously tampered areas in multimedia products. However a forged content containing a cloned fragile watermark can be constructed by using a series of watermarked data. To defeat this type of counterfeit attack, a novel fragile watermarking technique is proposed in which different pseudo-random data are selected for different host products, and the generated fragile watermark is dependent upon the selected information. While inserting the fragile watermark, the 相似文献