具有任意非线性输入的鲁棒模型参考自适应控制

提出了一种分析具有任意非线性输入的模型参考自适应(MRAC)的新方法,它不要 求对象是稳定的,允许系统存在未建模动态和有界扰动.同时给出了一种提高非线性输入自 适应系统特性的补偿方案,它通过在控制律中引入跟踪误差,可以提高系统的暂态及稳态精 度,而又不破坏MRAC系统的收敛特性.     

软腔体柔性机械臂的T-S模糊建模方法的研究

提出一种利用T-S模糊模型的柔性机械臂建模方法;柔性机械臂是一个高度复杂、高度非线性、高度耦合的非线性时变系统,而模糊模型本质上是一种非线性模型,可以任意精度逼近任何非线性系统;利用减法聚类算法离线辨识了T-S模型的前件参数,同时利用最小二乘法求得了T-S模型的后件参数;最后将模型的仿真结果和实验结果进行了对比分析,验证了模型的准确性;由此表明,柔性机械臂T-S模糊建模方法是有效的,它具有模糊模型的特点,可以任意精度逼近任何非线性系统,为柔性机械臂的模糊建模和下一步研究提供了理论指导及重要的前提条件.     

一维云模型系统的逼近性研究

针对云模型的基本原理,提出了一类云模型系统的设计方法,并利用Stone-Weierstrass定理对在3σ 正态分布随机数条件下的云模型系统任意逼近紧集上的任意连续实函数进行了证明, 是对云模型应用于逼近任意连续非线性函数理论的创新,也是今后云模型系统用于系统辨识和控制的理论依据.     

混杂切换Hamilton系统的H∞控制

研究含无穷个子模型的混杂切换Hamilton系统在（任意）切换路径下的H∞控制问题．对于系统存在外部干扰的情况,利用耗散Hamilton结构特性,给出系统在（任意）切换路径下的H∞控制器的设计方案;并将新结果用于一般非线性混杂切换系统中,得到了该类系统的H∞控制器．仿真例子验证了所得结果的正确性和实用性．     

基于粗糙集的高速公路交通流神经网络模型

利用粗糙集能够处理模糊、不确定知识和神经网络对非线性函数具有任意逼近能力的优点,提出一种粗糙集和RBF网络集成的动态系统建模算法。并利用这种方法建立具有复杂动态特性和不确定性的高速公路宏观交通流动态模型,仿真结果表明了该方法的有效性。     

基于规则的阀门非线性特性离散时间仿真模型

在控制阀非线性特性研究中,Choudhury模型得到了广泛应用。但在输入信号突变较大时,模型输出的阀位与实际阀位之间存在一定的偏差。此外,Choudhury模型只考虑了阀门非线性特性中的黏滞特性,而没有考虑间隙特性。在详细分析产生偏差原因的基础上,通过总结阀门输出特性的规律,增设多个描述阀门状态的变量,提出了一种新的基于规则的阀门非线性特性离散时间仿真模型。该模型对Choudhury模型进行了改进,同时包括了间隙特性。仿真表明在各种输入信号情况下,阀门非线性模型能够详细描述阀门的物理实际。同时,该模型能够用于计算机控制系统中阀门非线性特性的模拟。     

基于一种改进的BP神经网络光伏电池建模

由于光伏电池具有高度非线性特性,难以建模,而传统的数学模型难以满足光伏控制系统设计和应用的要求。该文利用神经网络具有逼近任意复杂非线性函数的能力,将神经网络技术应用到光伏阵的建模中,避开了该模块内部的复杂性。模型以太阳能日照、温度以及负载电压作为神经网络辨识模型的输入量,光伏阵输出电流为输出量,采用改进型BP算法,建立了光伏电池的动态响应模型,然后预测了最大功率点。文中给出模型的结构,训练步骤和仿真结果。仿真结果表明,方法可行,建立的模型精度较高,从而为设计光伏实时控制系统奠定了基础。     

MPSO-SVM的压力传感器的非线性校正研究

为了消除压力传感器受温度变化和电压波动的影响而产生的非线性特性,提出了改进粒子群优化支持向量机(MPSO-SVM)非线性校正,利用改进粒子群首先对支持向量机的参数进行搜索寻优,通过建立压力传感器输出特性与其实际电压值之间非线性映射关系的校正模型,再根据支持向量机具有逼近任意非线性函数的特点,实现压力传感器非线性校正。实验结果表明,压力传感器的最大相对波动从原来的22.2%降为0.12%,有效地消除了温度和电压波动的影响,此方法实现简单、成本低,具有实用价值。     

基于遗传优化的RBF-BP网络的实时故障检测

针对单一神经网络对复杂模型难以实时做出准确预测和BP神经网络自身的缺陷,结合RBF神经网络可以逼近任意函数的特性,提出了基于遗传优化的混合神经网络模型(RBF-BP)。由RBF网络和BP网络并联作为一个神经网络(简称为RBF-BP)的隐层,利用该网络对被控对象进行逼近训练、实时故障检测,该算法同时具有RBF网络和BP网络的优点,适用于复杂非线性系统的故障检测。     

通用神经网络非线性系统模型参考自适应控制*

针对任意复杂的具有最小相位,滞后环节和非最小相位特性的离散非线性系统,提出一种通用的直接神经网络模型参考自适应控制。采用具有在线学习功能的最近邻聚类算法训练RBF神经网络控制器,同时引入优化策略对聚类半径进行自动调整,并利用构造伪系统的方法构成一种对非最小相位同样有效的神经网络模型参考自适应控制器。仿真研究证明,该控制策略不仅能使多种非线性对象跟踪多种参考信号,而且抗干扰能力和鲁棒性也很好。     

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.