Comments on ＂How to repair the Hill cipher＂

A modification of the Hill cipher algorithm was recently proposed by Ismail et al.（2006）, who claimed that their new scheme could offer more security than the original one due to an extra non-linearity layer introduced via an elaborated key generation mechanism. That mechanism produces one different encryption key for each one of the plaintext blocks. Nevertheless, we show in this paper that their method still has severe security flaws whose weaknesses are essentially the same as that already found in the original Hill cipher scheme.     

语境对元语否定解读的制约

语境作为语用学中最为重要的概念,对元语否定的解读起着至关重要的作用。元语否定区别于普通否定在于语境因素的参与。语境就其本身而言内容纷繁杂多。着重对几类不同的语境如上下文语境,交际双方共享信息,普遍认知常识,特定交际相关知识以及法规和文化背景知识等对元语否定解读的制约进行论述。     

“否定”的诱惑:试析巴塞尔姆《白雪公主》的召唤结构

唐纳德·巴塞尔姆的《白雪公主》是后现代主义文学的主要代表之一。该小说独特的叙事方法与巧妙的人物塑造模式为读者留下许多等待填补的"空白"与"未知",形成强大的召唤结构。这种审美效果不断否定了读者的先在审美经验,促使读者对文本进行重构与再创造。强大的召唤结构使得这部小说像一坛佳酿,历久不衰、悠远留长。     

基于AES加解密系统的设计与实现

基于Windows XP操作系统,利用VC＋＋编程语言,实现了一个基于AES的加解密系统,该系统能对字符串和文件使用AES算法进行正确的加密和解密。     

“三段式”能否概括否定之否定规律——试析否定之否定规律的实质

黑格尔是第一个系统论述否定之否定规律的哲学家,他曾用正题、反题、合题来表述这一规律,并形容其途径好似"圆圈"。列宁继承并发展了他的合理内核,首先确定这是一种区别于形而上学的辩证的否定观,是事物发展联系的环节,是内部矛盾运动的结果,其本质是革命的、批判的。同时说明事物的发展是经历两次否定、三个阶段才确立为一个周期的。文章认为,这种"三段式"的节奏划分是合理的,但这并不能代表否定之否定规律的全部,除了这一个周期之外,就事物发展的整个过程而言,是由许多个首尾相连的近似"圆圈"的否定之否定,即多个周期构成的、螺旋式上升的长过程,是前进性与曲折性的统一。正是这种"螺旋式上升"的发展态势才反映出否定之否定规律的实质。     

On the Analysis of Negation in English Teaching

The negation in English is very complicated.It cannot be separated from the other parts of the whole sentence.We have to take all the factors of the whole sentence into account to understand the negation in English.This paper probes into the classification and the construction of the negation.It aims at providing a detailed analysis of negation in English teaching.