排序方式: 共有73条查询结果,搜索用时 0 毫秒
71.
首先分析了网络结构变化带来的问题,简述了协同式网络攻击和P2P,在此基础上提出了基于P2P的协同式网络攻击模型,并重点分析了系统最关键的部位:分布式智能专家系统。最后指出了模型在安全方面的缺陷,并提出了相应对策。 相似文献
72.
小波变换可以将音频边缘信息完整提出,利用边缘掩蔽水印信息,使水印算法具有透明性,基于此提出了一种基于离散小波变换的数字音频水印算法,该算法将能代表更多版权信息的二维图像信息经过Arnold置乱变换,嵌入到音频小波变换域的低频系数中.并将该算法与已有的离散余弦(DCT)水印算法相比较,发现该算法在抵抗剪切、加噪、滤波及压缩攻击方面要优于DCT水印算法. 相似文献
73.
New animal model of emotional stress: Behavioral, neuroendocrine and immunological consequences 总被引:3,自引:0,他引:3
LINWenjuan WANGWeiwen SHAOFeng 《科学通报(英文版)》2003,48(15):1565-1568
This report describes a new model of emotional stress, which was induced by randomly giving an empty water bottle to rats during watering periods per day for 14 consecutive days. The behavioral, endocrinological and immunological consequences were investigated. The data showed that the emotional stress activated both the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, leading to the increased blood levels of corticosterone and catecholamine. It also elicited attacking and exploring behavior, suppressed the immune function of the rats, including leukocyte counts, weight of the spleen, and the level of specific anti-ovalbumin IgG antibody production. Presenting no water and no empty bottle to rats only evoked the exploring behavior, increased the corticosterone level and decreased the leukocyte counts. These findings demonstrate a role of psychological factors on behavioral, endocrinological and immunological functioning. The animal model described in the present study may serve as an analogue mimicking emotional stress experienced in humans (e.g. anger and/or anxiety), and may be useful for further studying the complex relationships among emotional stress, behavior, and immune function. 相似文献