基于混沌序列的图像置乱加密算法

混沌序列具有易生成性,并且具有对初始条件强敏感性、伪随机性、可完全重现性等,基于以上特性提出一种基于混沌序列的图像置乱加密算法,即首先以初始条件为密钥生成混沌序列,然后依据该序列进行图像置乱。软件模拟实验证明该算法实现简单,且图像的解密结果对混沌序列的初始值有较强的依赖性,安全性高。     

一种混合级联混沌的伪随机序列生成方法

针对单混沌系统的参数空间较小及计算机有限精度限制问题,提出了一种混合级联混沌的伪随机序列生成方法.该方法利用混沌数值二进制序列的汉明重量控制选择不同的级联混沌映射进行迭代产生伪随机序列,然后再对其转换成二进制序列.生成的序列通过仿真表明其具有良好的密码学特性.     

基于云模型与Fibonacci的混沌伪随机序列发生器设计

结合云模型在精确数值间的随机性和模糊性,以及三阶Fibonacci序列产生速度快、可控参数多的特点,提出了一种将云模型与广义三阶Fibonacci相结合的混沌系统伪随机序列发生器。利用量子Logistic混沌系统产生的混沌序列作为广义三阶Fibonacci函数模型的参数,实现参数的动态随机更替;将云发生器产生的云滴群作为广义三阶Fibonacci函数的变量,再由广义三阶Fibonacci函数与Logistic映射级联耦合得到广义三阶Fibonacci混沌系统模型,基于此模型设计了一种伪随机序列发生器。实验分析表明,该发生器能快速并行产生混沌伪随机序列,具有结构简单、伪随机性强、分布均匀、相关性小等特征,并且每次产生的混沌伪随机序列都具有独立随机性,无法找到周期规律,从而克服了混沌伪随机序列发生器设计中存在的根本性缺陷。     

基于FFT与混沌的图像隐藏技术

提出一种基于FFT和混沌的图像隐藏算法.首先利用混沌系统产生混沌序列对秘密图像进行加密,然后利用FFT与混沌序列把秘密图像隐藏到载体图像中.实验结果表明,该算法具有良好的安全性和隐藏效果.     

基于混沌序列的数字水印的嵌入和提取方法

提出了一种基于混沌序列的数字水印嵌入和提取方法.因为混沌序列具有随机性,不容易被窃取,从而使得数字作品具有较强的抗攻击性,从而实现信息的隐藏.     

基于混沌掩蔽的保密通信方法(英文)

提出了一种新的基于混沌掩蔽的保密通信方法．在发送端,信息序列在与混沌掩蔽序列相加的同时还介入到该掩蔽序列的发生之中．在接受端,一个与发送端具有相同非线性函数形式的非动力学系统被用来从接受信号中提取混沌掩蔽序列,然后再与接受信号相减以恢复信息序列．理论分析和计算机模拟表明,该方法保密性好、可靠性高且实现容易．     

一种基于混沌的图像随机置乱加密算法

在分析混沌特性的基础上,设计一种基于Logistic混沌序列的图像像素点随机置乱加密算法,将混沌映射后的图像序列,再通过一组随机排序的序列进行置乱处理,最终得到加密图像。仿真实验结果表明,该算法效率高、安全性好,并具有一定抗攻击能力。     

柳江径流混沌时间序列的平均周期分析

以柳江历年年径流总量时间序列、近十年日最高水位时间序列及Henon系统产生的混沌序列为原始数据,计算这三个混沌序列的八个平均周期.研究发现对于柳江径流数据与Henon系统数据,八种平均周期数据性质变化一致;而针对柳江径流数据的物理意义,对计算结果综合理论分析,则以功率加权计算得到的平均周期,在径流的混沌特性分析过程中更具有实际意义.     

基于Volterra级数的RLS自适应算法的混沌时间序列预测

根据混沌序列产生的确定性和非线性机制,基于Volterra级数和RLS算法,提出了一种少参数二阶非线性滤波算法用于混沌时间序列的自适应预测。仿真结果表明,这种非线性自适应滤波器能有效地预测一些超混沌序列,而且该滤波器的一步均方误差性能明显高于其他基于Volterra级数的NLMS算法,表明该算法具有良好的收敛性能。     

混沌数字水印信号研究

探讨了使用M序列作为数字信号方法的优缺点,分析了混沌映射和混沌水印序列的统计特性,在此基础上,对混沌序列数字水印信号与M序列数字水印的性能进行了分析比较,指出混沌序列是最适合作为数字水印信号的序列.     

我国劳动教养制度探微

劳动教养制度是一项极具中国特色的制度,它的独特之处就在于直接映射出了刑事政策理念的悄然转变,刑事政策理念的转变又不可避免地将该制度的生存推向难以为继的尴尬境地。随着我国刑事政策理念的转变,这种制度的许多难以解决的诟病日益凸显,其与法治背景的对立使之必须面对一场深刻的变革。     

《西游记》姓阎不姓吴

笔者一直力主古典小说《西游记》是由诞生于关中的全真道道士们推动创作的,其最终定稿者是明代万历时期的江苏茅山乾元观全真道道士阎希言师徒。《西游记》扉页署名＂华阳洞天主人校＂,实际是暗示其最终定稿者是茅山乾元观全真道道士阎希言师徒。     

Educational leadership and change: structural challenges in the implementation of a shifting paradigm

A great deal of research has been conducted regarding leadership and change. The impact of this research has not been limited to academe, but rather, government policy in different jurisdictions has been directly impacted by developments into collegial forms of leadership. While the positive correlation between leadership and change has been widely acknowledged, this article argues that a disconnect has emerged between the theory and practice signifying that the efficacy of change remains hampered by structural constraints and subjective factors that result in unpredicted outcomes. To explore this thesis, the fundamentals of educational leadership theory, our ability (or inability) to manage change and an analysis of the difficulties faced by leaders as they move from theory to praxis are examined.     

自然精神的探求与美学重构

一直以诗人之名和大量的诗歌创作成就享誉四川当代文坛的作家牛放,近年来却笔锋一转而创作出了为数不少的散文佳作,并在不长的时间内推出了散文集<牛放散文选>.他的散文不仅有别于长期居处在大都市的散文作家的创作,也迥异于一直专事散文的专业散文家的创作,非常强烈地表现出对自然精神的探求及其对这种精神进行美学重构的意愿.本文便是对作家在散文中表现出的这种探求精神的阐释.     

毛泽东对认识近代中国社会性质的历史贡献

以毛泽东为代表的中国共产党人。在马克思列宁主义理论的指导下。对近代中国社会性质问题进行了严肃思考和理论创造。随着中国革命实践的发展．以毛泽东为代表的中国共产党人对近代中国社会性质的认识不断得到深化和发展，从而对近代中国社会性质作出了正确分析和科学判断。并成为中国共产党人的共识，为广大人民群众所接受。对认识近代中国社会性质作出了巨大的历史贡献。     

刑讯逼供的原因透析

刑讯逼供作为一种严重侵犯人权的行为，长期以来，禁而不止，在全国范围内普遍存在、泛滥成灾。本文对刑讯逼供原因作了粗浅的分析。     

引导学生自主学习的教学方法

对于引导学生自主学习的教学方法进行了初步的探索,分析了实现自主学习学生应具备的能力,介绍了德国Oskar-Von-Miller学校为学生提供的自主学习平台,并对如何引导学生自主学习进行了研究,提出了引导学生自主学习的教学方法。     

Moving Forwards,Sideways or Backwards? Inclusive Education in Samoa

The introduction of inclusive education (IE) has been promoted to meet the needs of all students. Initially this was a western-driven ideology but has been adopted by numerous developing countries such as Samoa. In this country, the education of students with special learning needs has followed the usual pattern of development from voluntary provision to government-funded segregated placements, followed by mainstreaming, and finally inclusion in regular schools. This qualitative phenomenologically oriented study gathered data from educators and parents about their perceptions of IE and how it was being implemented. The results indicated that this has not always been an easy transition and many participants in the study, although subscribing to the notion of IE, believe that there are a number of implementation difficulties, particularly around issues of support. In relation to this, IE is regarded as a borrowed policy that has overlooked cultural issues and ownership. A model for future developments is outlined and recommendations for future research are indicated.     

The seeming ‘round trip’ of learner-centred education: a ‘best practice’ derived from China’s New Curriculum Reform?

ABSTRACT

Inspired by the ‘advanced’ Western experience, China has implemented the New Curriculum Reform promoting learner-centred education since 2001. The OECD has identified this reform as a key feature contributing to Shanghai’s ‘PISA success’, worthy in turn of re-imitation by the West. Drawing upon official documents and interview data, this article shows that learner-centred education has been well accepted in rhetoric, which has led to more time being given to pupil activities. However, in reality, teaching and learning practices have continued to reflect what Confucian scholars have persistently advocated. Moreover, this article illustrates that the ‘round trip’ of learner-centred education between the East and the West has only taken place on the surface. The Chinese government has relied on the transformed Western concept for policy legitimacy, while international policy agencies have nevertheless deployed the case of China as an ideal exemplar to justify this Western concept as a global ‘best practice’.