基于Logistic映射的虚拟仪器混沌信号产生

讨论了基于虚拟仪器产生Logistic混沌序列并转换为时间信号的方法,实验的结果表明,用该方法产生Logistic混沌信号,具有信号纯净、噪声小、参数调节简便、控制容易的特点。文章设计的虚拟混沌信号发生器,既可作为外部信号源,也可作为仿真信号源来提供研究和应用。     

基于小波包分解的自适应盲脆弱水印算法

提出了基于图像内容自嵌入功能的脆弱水印算法．算法的新颖之处在于能区分图像内容、水印还是两者同时被篡改,由原图像高7位的一级小波低频系数量化得压缩图像,转换成二进制作为水印,混沌置乱加密后嵌入到原图像的LSB．认证时,由认证图像高7位制作的水印与提取水印的差值来确定图像是否遭到窜改,可定位篡改位置．实验结果表明：与Y-M算法相比峰值信噪比提高了5个dB,与WONG算法相比峰值信噪比提高了3个dB,实现了盲检测,而且该算法能够检测常见的攻击如噪声、几何剪切、滤波等．     

混沌理论对实验室研究的启示

20世纪70年代末混沌理论的提出,已经对实验室研究领域存在广泛的渗透,对传统实验室研究的简单线性、可预测性、独立和封闭性产生了巨大的冲击。实验室是一个动态发展的系统,处在不断的变化之中,其研究过程本身就是一个动态变化发展的过程。用混沌理论视角思考实验室研究,可以拓宽实验室研究的视野并从中得到启示。     

Emergency Communication Challenges in Response to Hurricane Katrina: Lessons from the Centers for Disease Control and Prevention

In response to Hurricane Katrina's extensive destruction and related public health threats, the Centers for Disease Control and Prevention (CDC) deployed more than 1,000 staff to its emergency operations center and to affected areas. Among them were members of CDC's Emergency Communication System. This paper describes the strategies and tactics used by health communication specialists during the pre-event, response, and post-event stages to address a range of emergency communication exigencies. It highlights three difficult challenges for CDC communication specialists during Hurricane Katrina: rapid dissemination of health messages; adaptation of health messages for diverse audiences, locations, and circumstances; and phasing of key risk messages during the emergency response.     

基于Logistic映射的虚拟仪器混沌信号产生

讨论了基于虚拟仪器产生Logistic混沌序列并转换为时间信号的方法,实验的结果表明,用该方法产生Logistic混沌信号,具有信号纯净、噪声小、参数调节简便、控制容易的特点。文章设计的虚拟混沌信号发生器,既可作为外部信号源,也可作为仿真信号源来提供研究和应用。     

Chaos,poverty, and parenting: Predictors of early language development

Studies have shown that distal family risk factors like poverty and maternal education are strongly related to children's early language development. Yet, few studies have examined these risk factors in combination with more proximal day-to-day experiences of children that might be critical to understanding variation in early language. Young children's exposure to a chronically chaotic household may be one critical experience that is related to poorer language, beyond the contribution of SES and other demographic variables. In addition, it is not clear whether parenting might mediate the relationship between chaos and language. The purpose of this study was to understand how multiple indicators of chaos over children's first three years of life, in a representative sample of children living in low wealth rural communities, were related to child expressive and receptive language at 36 months. Factor analysis of 10 chaos indicators over five time periods suggested two factors that were named household disorganization and instability. Results suggested that after accounting for thirteen covariates like maternal education and poverty, one of two chaos composites (household disorganization) accounted for significant variance in receptive and expressive language. Parenting partially mediated this relationship although household disorganization continued to account for unique variance in predicting early language.     

Improving the work climate in a TVET college through changing conversations

Abstract

As an HRD manager in a college, I am responsible for employee wellness within the organisation. However the culture of the college in which I work is toxic, characterised by bullying, destructive leadership, gossip and victimisation. Such a culture is difficult to change and requires a different approach to the expert-led, training interventions that are underpinned by diagnostic organisational development. In this article, I provide evidence that supports my claim that a participatory action research approach, embedded within a dialogic organisational development paradigm, succeeded in improving the work climate as it enabled individuals to identify the factors which contributed to the toxic environment and take action to improve it. The participatory methods employed allowed the x participating college mangers to deal with their own feelings, and enabled them to describe and evaluate the workplace climate as toxic. Armed with a discourse to discuss the problem, they were able to move from helplessness and self-blame to acceptance of responsibility for change. Viewing the problem as a systemic issue enabled them to understand how to modify their practice to embody life-enhancing values that diminished the toxic patterns of communication. By changing conversations, negativity was diminished and negative interactions were replaced by more positive workplace relations. The process described in this account of my learning may be useful to improve the climate in other similarly toxic workplaces.     

通过Melnikov函数和微扰法来预测平面Josephson方程的混沌

利用梅尔尼科夫（Melnikov）函数法预测平面约瑟（Josephson）方程具有斯梅尔马蹄变换（Smale horseshoes Transformation），应用微扰法对约瑟夫森方程在ε（t）＝0和ε（t）≠0，两种条件下求出了方程的解。     

基于混沌理论的学校管理反思、批判与创新

学校是一个开放、耗散且充满混沌现象的系统,学校管理者应有混沌理论的概念、知识、态度与敏锐度,重视学校内部的沟通与协调、反馈机制。但混沌理论易造成学校管理人员神经处于紧绷状态,且难以清楚说明哪些初始事件是学校管理者必须正视的因子,学校管理中奇异吸引子到底是什么,学校中人、事、物的互动关系无法完全加以预测。基于此,提出了六条学校管理创新性思维,即:未来感与使命感相统一,综观俯视全局进行顶层设计;危机感与敏觉性相统一,微观处理学校内外部环境的蝴蝶效应;领导力与沟通力相统一,以激励与权变来塑造混沌背景下的新管理范式;创造力与行动力相统一,在学校生态非线性的走向中积极自我突破;知识力与求知欲相统一,学校变革与奇异吸引子的寻求;说服力与活力相统一,视非均衡系统中的冲突为必然。     

Nonlinear dynamics analysis of a new autonomous chaotic system

In this paper,a new nonlinear autonomous system introduced by Chlouverakis and Sprott is studied further,to present very rich and complex nonlinear dynamical behaviors. Some basic dynamical properties are studied either analytically or nu-merically,such as Poincaré map,Lyapunov exponents and Lyapunov dimension. Based on this flow,a new almost-Hamilton chaotic system with very high Lyapunov dimensions is constructed and investigated. Two new nonlinear autonomous systems can be changed into one another by adding or omitting some constant coefficients.