选注者言:吸烟者常可寻到这样一种自慰:我吸的烟是“低焦油的”、或者是“超 低焦油的”。因为香烟的包装壳上有明明白白的标示。本文告诉读者一个难以置信却又是真实的情况: So at a time when we've had this huge decline in the...选注者言:吸烟者常可寻到这样一种自慰:我吸的烟是“低焦油的”、或者是“超 低焦油的”。因为香烟的包装壳上有明明白白的标示。本文告诉读者一个难以置信却又是真实的情况: So at a time when we've had this huge decline in the machine measurement oftar and nicotine(尼古丁), and a huge shift measured by some of the cohort(一群)studies we've had, during that same period we see an increase in the lung cancerdeath rates, 这段文字的大意是:以机器测量,“低焦油的”香烟所含尼古丁确比其他香烟有大幅下降,但是,此类香烟导致肺癌的死亡人数却上升了！ 原因很简单:...smokers do not inhale the same way the the test machines do, sothey usually are exposed to much more tar than the tests would indicate.因此,人们对政府的机器测量尼古丁的方法给予否定: ...rising disease rates among smokers since'light' cigarettes were introduceddemonstrate the failure of the current federal testing system.展开更多
Compared with the traditional crypto- graphy, visual cryptography （VC） decrypts secret images referring to the characteristics of human vision, rather than the cryptography knowledge or complex computations. Further...Compared with the traditional crypto- graphy, visual cryptography （VC） decrypts secret images referring to the characteristics of human vision, rather than the cryptography knowledge or complex computations. Furthermore, seeing to the freeness of the secret key, the whole process of encryption as well as deeryption for the visual cryptography meets a fast dealing course. As to the security concern, it is able to guarantee that no one can have access to any clues about the content of a secret image from individual cover images. Thus, owing to the studies on this area, the target of light-weighted cryptography is reached. Now the visual cryptography has been developed from the meaningless shadows to the meaningful ones. Seeing to the highly developed technique, some advanced VC techniques are introduced in this survey, respectively.展开更多
文摘选注者言:吸烟者常可寻到这样一种自慰:我吸的烟是“低焦油的”、或者是“超 低焦油的”。因为香烟的包装壳上有明明白白的标示。本文告诉读者一个难以置信却又是真实的情况: So at a time when we've had this huge decline in the machine measurement oftar and nicotine(尼古丁), and a huge shift measured by some of the cohort(一群)studies we've had, during that same period we see an increase in the lung cancerdeath rates, 这段文字的大意是:以机器测量,“低焦油的”香烟所含尼古丁确比其他香烟有大幅下降,但是,此类香烟导致肺癌的死亡人数却上升了！ 原因很简单:...smokers do not inhale the same way the the test machines do, sothey usually are exposed to much more tar than the tests would indicate.因此,人们对政府的机器测量尼古丁的方法给予否定: ...rising disease rates among smokers since'light' cigarettes were introduceddemonstrate the failure of the current federal testing system.
基金supported by National Science Council under Grant No. NSC98-2218-E-035-001-MY3
文摘Compared with the traditional crypto- graphy, visual cryptography （VC） decrypts secret images referring to the characteristics of human vision, rather than the cryptography knowledge or complex computations. Furthermore, seeing to the freeness of the secret key, the whole process of encryption as well as deeryption for the visual cryptography meets a fast dealing course. As to the security concern, it is able to guarantee that no one can have access to any clues about the content of a secret image from individual cover images. Thus, owing to the studies on this area, the target of light-weighted cryptography is reached. Now the visual cryptography has been developed from the meaningless shadows to the meaningful ones. Seeing to the highly developed technique, some advanced VC techniques are introduced in this survey, respectively.
