一种差分进化算法优化小波神经网络及其在弱信号检测中的应用

在混沌理论和相空间重构技术的基础上,提出了一种基于小生境自适应差分进化小波神经网络(NADE-WNN)的混沌背景下弱信号检测方法。该方法采用小生境自适应差分进化算法同时优化小波神经网络的结构和参数,简化网络结构,提高网络的学习精度和收敛速度。实验结果表明,与传统的RBF神经网络和小波神经网络预测混沌时间序列的性能相比,该算法优化的小波神经网络具有更高的预测精度和收敛速度,能够较好地检测出混沌背景下的弱信号。     

改进PSO优化BP神经网络的混沌时间序列预测

为提高BP神经网络预测模型的预测准确性,提出了一种基于改进粒子群算法优化BP神经网络的混沌时间序列预测方法。引入自适应变异算子对陷入局部最优的粒子进行变异,改进了粒子群算法的寻优性能; 利用改进粒子群算法优化BP神经网络的权值和阈值,训练BP神经网络预测模型求得最优解。将该预测方法应用到几个典型的非线性系统的混沌时间序列进行有效性验证,结果表明了该方法对典型混沌时间序列具有更好的非线性拟合能力和更高的预测准确性。     

听觉信号盲分离的混合粒子群优化算法

为了解决基本粒子群盲分离算法收敛速度慢、优化精度低的问题,提出用基于群体自适应变异和个体退火操作的混合粒子群优化算法（HPSO）来实现听觉信号盲分离。与模拟退火算法（SA）和基本粒子群算法（PSO）相比,该算法保持了基本粒子群算法简单、容易实现的特点,又能进行自适应变异,改善了其摆脱局部极值点的能力。仿真对比结果表明,基于该改进算法的盲分离效果良好,具有收敛速度快、性能稳定等特点。     

基于多策略粒子群优化RBF的云资源预测模型

针对云计算资源利用率低等问题,构建基于多策略粒子群优化RBF神经网络的云资源预测模型(MPSO-RBF)。采用改进的粒子群算法对RBF神经网络参数进行优化,避免随机初始化参数引起的预测精度低等问题;对于粒子群容易陷入局部最优解等问题,采用动态惯性权重、自适应学习因子和变异粒子位置3种策略对粒子群进行改进,提高算法的寻优能力。基于云计算资源负载数据,将该模型与BP、RBF和PSO-RBF模型进行对比实验,验证了该模型具有良好的性能。     

基于自适应混沌粒子群优化的防空目标分配

粒子群优化算法存在早熟收敛和搜索精度较低的问题.为此,提出一种基于自适应混沌粒子群的优化算法.采用自适应权重和遗传算法中的交叉、变异操作更新粒子群,增加种群粒子的多样性,运用早熟判断机制判断粒子的当前状态,当粒子处于早熟状态时,利用混沌搜索的方法引导群体快速跳出局部最优.仿真结果表明,该算法可以有效解决粒子群算法的早熟问题,提高搜索精度和收敛速度.     

基于粒子群神经网络线控转向故障诊断的研究

改进的自适应粒子群优化算法根据群体早熟收敛程度和个体适应值来调整惯性权重和阈值系数,以及对粒子速度与位置进行更新,该算法兼顾全局寻优和局部寻优,有效地避免早熟收敛.使用改进的自适应粒子群优化算法训练神经网络,并根据汽车线控转向系统构建故障诊断模型.实验结果表明:与传统的粒子群优化算法、遗传算法训练神经网络相比,基于改进的自适应粒子群优化算法的神经网络能够有效改善神经网络的训练效率,加快了收敛速度,提高故障模式识别的准确率.     

基于粒子群优化的RBF神经网络模型研究

在本文中,提出了采用粒子群算法来优化RBF神经网络,并建立了这种新的混合模型。在这个粒子群和RBF神经网络的混合模型中,粒子群优化算法应用于选择中心节点和隐藏节点的宽度以及输出向量方面,对RBF神经网络建立了5个输入节点,6个隐藏节点和一个输出节点。通过对粒子群优化的RBF神经网络模型对一些地区的结核病发病趋势进行预测,得出这种混合模型对结核病发展趋势进行预测能够取得较好的预测结果。     

基于有效K均值有效极限学习机的混沌海杂波背景中微弱信号检测

为了在复杂混沌噪声背景中快速准确提取有用信号,提出基于复杂非线性系统相空间重构理论,采用改进极限学习机(ELM)预测单步误差检测微弱信号的方法。采用改进K均值聚类算法选择最优族作训练集,改进极限学习机选择权值和偏置的方法进一步提高检测的精度和速度,采用Lorenz系统建立了混沌噪声序列的一步预测模型,从预测误差中检测湮没在混沌噪声中的微弱目标信号(包括周期信号和瞬态信号),然后使用加拿大Mc Master大学IPIX雷达数据,在海杂波噪声中提取漂浮物信号作为实验研究。结果表明该方法能够有效检测混沌背景噪声中极微弱信号,同时抑制噪声对混沌背景信号的影响,与径向基函数(RBF)神经网络等传统算法相比,预测精度提升了25%,检测门限提高了-5 dB,同时训练用时减少77.1 s,在实际应用中具有更明显优势。     

混沌粒子群优化神经网络在铁路客运量预测中的应用

针对常规RBF神经网络在铁路客运量预测中存在的收敛速度慢、易陷入局部极小等缺陷,提出一种基于混沌粒子群优化RBF神经网络算法,实现对RBF神经网络参数进行优化,并对我国1985年-2008年铁路客运量数据进行仿真实验。仿真结果表明,该算法很好地解决常规RBF神经网络参数优化问题,提高了铁路客运量预测精度,预测结果对铁路企业的决策有更加实用的参考价值。     

一种改进PSO优化RBF神经网络的新方法

为了克服神经网络模型结构和参数难以设置的缺点,提出了一种改进粒子群优化的径向基函数(RBF)神经网络的新方法.首先将最近邻聚类用于RBF神经网络隐层中心向量的确定,同时对引入适应度值择优选取的原则对基本粒子群算法进行改进,采用改进粒子群(IMPSO)算法对最近邻聚类的聚类半径进行优化,合理的确定了RBF神经网络的隐层结构.将改进PSO优化的RBF神经网络应用于非线性函数逼近和混沌时间序列预测,经实验仿真验证.与基本粒子群(PSO)算法,收缩因子粒子群(CFA PSO)算法优化的RBF神经网络相比较,其在识别精度和收敛速度上都有了显著的提高.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.