多变量系统的PID 控制器设计

针对多输入多输出系统,提出一种基于微粒群算法的灰色系统预测PID 控制算法．该方案将多 输入多输出系统转化成若干个多输入单输出子系统,使用多变量一阶灰色模型GM(1;N) 预测出每个子系统的 输出,实现了多输入多输出系统的对角解耦．然后用微粒群算法优化PID 控制器的参数,用优化后的PID 控 制器对每个子系统进行控制．对两个典型的多变量控制过程进行了仿真,结果表明,这种控制方法超调量较 小,鲁棒性强,响应速度快,抗干扰能力强.     

基于PSO算法的目标值前馈型二自由度PID控制器的优化设计

微粒群优化算法是一种全局优化技术，算法简单、容易实现．其通过微粒间的相互作用发现复杂搜索空间中的最优区域．提出了将微粒群优化算法用于二自由度PID控制器参数的寻优设计中，并以工业过程中常见的对象为模型，进行了Matlab仿真试验，仿真结果表明系统同时具有了最优的目标值跟踪特性和干扰抑制特性，证明了PSO算法的有效性．     

利用改进微粒群算法优化PID参数

提出一种利用改进微粒群算法优化PID参数的方法。微粒群算法(PSO)是一种随机全局优化技术，算法通过微粒间的相互作用发现复杂搜索空间中的最优区域，算法简单、容易实现且功能强大。将PSO算法加以改进并应用在PID控制器的参数优化，经仿真证明了PSO算法的有效性，其性能优于遗传算法和传统的经验公式。     

基于控制理论的微粒群算法分析与改进

利用控制理论对基本微粒群算法、标准微粒群算法及带有收缩因子的微粒群算法进行了详细的分析，结果表明它们或为一个积分环节与两个惯性环节组成的系统；或为三个惯性环节组成的系统．为了提高算法效率，建立了由积分环节与震荡环节组成的系统所对应的改进微粒群算法，并讨论了参数的选择方法．仿真实例证明了该算法的正确性与有效性．     

基于复合正交神经网络的灰色PID控制

结合传统反馈控制方法和灰色预测控制的预测控制器已在控制系统中获得了成功的应用。由于复合正交神经网络具有学习算法简单、收敛速度快,有逼近线性或非线性函数的优良特性。与灰色预测方法相比,神经网络预测精度高,且误差可控,如果把神经网络作为灰色预测器,建立一种灰色预测控制,那么就会在控制系统中获得良好的控制性能。为此,提出一种结合传统的PID控制和神经网络灰色预测补偿的灰色PID控制器,可对系统进行在线灰色估计和控制,由复合正交神经网络对不确定部分建立的灰色预测模型,可根据系统的参数变化来自动调节预测补偿值,使系统响应具有适应性。仿真结果表明,与传统的PID控制方法相比,该控制器可获得更为优良的动态性能和鲁棒性。     

基于粒子群优化的分数阶PID预测函数参数整定

为避免分数阶PID预测函数手动调节参数的不确定性以及繁琐性,应用粒子群算法优化其参数,完善分数阶PID预测函数控制器,并提高其控制精度,充分体现了算法的智能性。将粒子群整定分数阶PID预测函数算法应用于单变量的励磁控制系统中,通过Matlab仿真并与模糊分数阶PID预测函数以及经验调节方法相比较,结果表明,粒子群算法整定参数收敛速度快,找到最优点时间短,整定后的算法具有静态误差小、无超调、上升速度快、调节时间短、抗干扰能力强等优点,能很好地满足励磁系统的动态特性,并具有较强的鲁棒性及适应性。     

基于改进微粒群神经网络的油料储备预测

根据油料储备历史数据样本进行油料储备预测,是实施油料保障有效举措.油料储备预测是具有不确定性、突变性的多变量复杂系统,预测难度大.为了解决采用传统预测法所存在的局限性,将微粒群优化算法与神经网络相融合,提出了改进微粒群神经网络的油料储备预测模型.利用神经网络自学习能力,捕捉预测系统非线性关系.将神经网络参数映射为实数码微粒,构造复合适应度函数.引入微粒距离系数,动态调整微粒速度和位置进化参数.借助微粒群优化算法较强全局搜索能力,训练神经网络参数,优化其结构,消除神经网络训练收敛慢、易陷入局部极值等现象.仿真实例表明,改进模型预测精确性评价指标良好,建模复杂度较低.     

基于微粒群算法的PID参数优化及其在电阻炉温度控制中的应用

PID控制在工业上广泛应用;但是PID参数整定困难。该文提出一种改进的微粒群算法,进行PID参数寻优,并应用于电阻炉温度控制。仿真证明了该算法能有效地实现PID参数整定,应用于电阻炉温度控制时,具有响应快,超调小等优点。     

微粒群算法的统一模型及分析

通过分析已有的几种微粒群算法,提出了一种统一模型,并通过线性控制理论分析了其收敛性能．为了进一步提高算法效率,提出了两种增强全局搜索性能的参数自适应算法：单群体参数自适应微粒群算法及双群体参数自适应微粒群算法．其中单群体参数自适应微粒群算法在进化初期使用算法发散的参数设置,从而能更大程度地提高算法全局收敛能力．双群体参数自适应微粒群算法使用两个种群,一个执行全局搜索,另一个执行局部搜索,通过信息交流以提高算法性能．仿真实例证明了算法的有效性．     

微粒群算法在PID参数优化中的应用

微粒群算法是近年来兴起的一种智能优化算法,PID控制是当前工控领域运用最为广泛的一种控制方案,PID控制的效果与其三个参数息息相关,参数的设置与选取直接影响到控制系统的性能,本文基于MATLAB GUI设计出了可视化的仿真平台,利用PSO算法针对炼钢炉铁水温度控制系统PID控制器参数优化进行仿真研究,并和其它几种方案的控制效果进行比较,得出PSO算法应用于PID参数整定的可行性、有效性和优越性。     

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.