一种改进的自抗扰解耦方法及其应用仿真

针对一类多入多出系统的解耦问题,提出了一种基于扩张状态观测器(ESO)的动态解耦方法。将系统输入变量间的耦合作用,被控对象参数时变和外界干扰视为一个总的扰动,用ESO估计扰动并反馈到控制器进行补偿,从而实现动态解耦,对解耦后的子系统按照极点配置方法设计出控制器。采用参数动态确定法确定ESO的参数。上述动态解耦方法简化了解耦过程,放松了对系统模型精度的要求,计算量小,响应速度快,鲁棒性强。并通过对常压蒸馏塔模型进行仿真控制,并与模糊PID解耦控制方法对比,结果表明本方法有效可行。     

基于蚁群算法的航空发动机PID参数优化

提出一种基于蚁群算法的PID参数优化控制算法,对航空发动机的双变量解耦控制方法进行了研究.蚁群算法采用分布式并行计算机制,易于与PID控制方法结合,优化后的控制器克服了传统的PID控制参数不易整定的缺点,且控制器结构简单规范、动态和静态性能良好,具有较强的鲁棒性.仿真结果表明该控制系统实现了解耦控制,对航空发动机模型参数在大范围内的变化均有良好的控制效果.     

基于表贴式永磁同步电机模型改进的自抗扰控制器

在使用自抗扰（Active Disturbance Rejection ControI er,ADRC）控制器的表贴式永磁同步电机（Surface Permanent Magnet Synchronous Motor,SPMSM）系统中,电流环依然存在耦合现象,扩张状态观测器（Extended State Observer,ESO）对于变化较大的扰动难以保证对其的估计精度。为了提高负载的动态性能,提出了改进的自抗扰控制器设计方案。基于表贴式永磁同步电机模型,利用最小二乘算法辨识出电流环参数,对电流环模型进行补偿,实现电流环的精确解耦,减小ESO对扰动估计的压力,提高扰动估计精度。仿真结果表明,改进的自抗扰控制器提高了负载的动态性能。     

热连轧板宽板厚的实用自抗扰解耦控制

针对热连轧板宽板厚多变量系统存在强耦合、大时滞和随机不确定等难题,提出了一种线性自抗扰动态解耦方案.考虑到系统的大时滞问题,在常规的降阶扩张状态观测器(ESO)之前,增加了一个纯时滞环节.为了把所设计的实用自抗扰控制(ADRC)与常规PID控制器进行公平比较,各控制器的最佳参数均采用变尺度混沌优化方法得到.仿真结果表明,优化后的ADRC不仅具有较好的解耦性能,而且对模型参数的不确定性和外扰具有较强的鲁棒性和参数适应性.     

立方体机器人自抗扰平衡控制方法

针对立方体机器人动力学模型多变量、强耦合的问题,提出一种基于自抗扰控制的平衡控制器设计方法.引入虚拟控制量,并在控制量与输出向量之间并行地嵌入多个自抗扰控制器,从而实现对多变量系统的解耦控制,将系统的动态耦合和外部扰动视为各自通道上的自抗扰控制器的总扰动,在为期望姿态安排过渡过程基础上,设计扩张状态观测器对总扰动进行估计并实时补偿.综合采用经验试凑法和带宽法对控制器参数进行整定,对自抗扰控制器系统进行稳定控制、姿态跟踪、抗扰性和鲁棒性实验,并与PID控制系统进行定量对比分析.仿真结果表明,所设计的自抗扰控制器不仅能有效实现立方体机器人的平衡控制,而且较PID控制器具有更好的响应速度、控制精度和强鲁棒性.     

球磨机制粉系统参数自整定PID解耦控制器

针对球团厂钢球磨煤制粉系统具有多变量强耦合、时滞、非线性以及生产工况变化大的复杂性,已有的控制方法难以满足其控制要求的现状,以磨煤机的数学模型为依据,提出了一种新型的多变量PID解耦控制策略.该控制系统由比例因子模糊自整定单元、PID控制器和基于对角矩阵法的解耦补偿器组成;PID控制器参数由粒子群算法进行优化.仿真结果表明,所建模型和所提控制方法的有效性.该方法可在大范围内解决系统的非线性和强耦合问题,具有较强的鲁棒性和运行工况适应性.     

倒立摆的自抗扰解耦控制方法研究

针对高阶次、多变量、强耦合的倒立摆系统,提出了基于自抗扰解耦控制方法对其进行控制。该方法采用双通道复合控制的方式,突破摆角和小台车相耦合作用的定位控制难点,完成摆角和小台车精确定位控制。采用该方法无需进行精确的输入变量与输出变量配对,只需要对控制作用的耦合矩阵进行静态解耦,分别构建控制通道。对于模型摄动造成的影响和各子对象间的动态耦合作用可由状态观测器（ESO,extended state observer）来估计并反馈到控制器以进行补偿。最终通过调节控制系统的相关参数,达到摆角和小台车位移相耦合作用的定位控制。仿真结果表明：该方法能够完成摆角和小台车位移相耦合作用的定位控制,瞬态性能和稳态性能好,超调量小,具有良好的控制效果。     

基于BP神经网络的多变量PID解耦控制

基于神经网络的智能PID控制策略，以经典的PID控制理论为基础，并通过具有多变量解耦控制自学习功能的神经网络参数整定来实现。本文给出了网络的结构和算法，示出了一组二元变量强耦合时变系统的实时仿真结果。通过计算机仿真证明，基于神经网络的PID控制具有良好的自学习和自适应解耦控制能力。该系统融解耦器和控制器于一体，易于实现，适用于非线性多变量系统的解耦控制。它使解耦后的系统具有较好的动态和静态性能，特别是当根据BP控制规律确定了网络连接权系数的初值时，还能使系统参数快速收敛。     

基于RBFNN的非线性多变量系统的控制策略研究

针对非线性多变量大时滞系统,研究了一种基于神经网络的智能控制策略。它以经典的PID控制为基础,通过神经网络参数整定,用于多变量系统的解耦控制;用预测模型超前预测系统输出,以克服系统的时滞。该文给出了网络的结构和算法,对一组二变量强耦合时变系统进行了仿真。仿真结果表明,控制器能根据系统运行状态获得对应于某种最优控制律下的PID参数,解耦后的系统具有较好的动态和静态性能。该方法具有控制精度高、响应速度快的优点,并具有较强的自适应性和鲁棒性。     

强制循环蒸发系统的非线性自适应解耦PID控制

本文结合现场的实际过程数据,首先应用能量平衡建立了强制循环蒸发过程的动态模型.针对该过程的多变量、非线性以及强耦合特性,在常规增量式PID控制器的基础上提出基于神经网络与多模型切换的非线性自适应解耦PID控制策略.该控制器是由线性自适应解耦PID控制器和基于神经网络的非线性自适应解耦PID控制器以及切换机构组成.其中线性自适应解耦PID控制器可以保证系统的稳定,而基于神经网络的非线性自适应解耦PID控制器则可以有效地提高系统的性能.上述过程的PID参数是通过广义预测的方法得到,最后通过仿真表明,上述控制方法不仅消除了回路间的耦合,在稳定生产的同时提高了蒸发的效率.     

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.