基于混合粒子群算法的多变量解耦控制器优化

研究薄膜厚度系统控制器优化问题,由于神经网络初始权值难以确定,使PID神经网络对控制器参数的自适应、自学习能力变差,最终导致控制效果不理想.为了解决这一问题,提出一种混合的粒子群算法,用来优化神经网络初始权值,进而实现控制器的优化,并应用于薄膜厚度控制系统.仿真结果表明:与PID神经网络控制器相比,优化后的控制器更好的实现了多变量控制系统的解耦控制,提高了控制器参数的自适应自学习能力,控制效果明显,并且系统的鲁棒性较好.     

基于蚁群神经网络的工业自动化PID参数优化

针对常规方法无法获得最优PID控制器参数的缺点,提出一种基于蚁群神经网络的PID控制器参数优化方法（ACO-RBFNN）。ACO-RBFNN将PID控制器的3个参数作为RBF神经网络的输入,系统输出为RBF神经网络期望输出,通过蚁群算法对RBF神经网络的参数进行优化,并通过RBF神经网络构造参数自学习的PID控制器,从而实现PID控制器参数在线优化。仿真实验结果表明,基于ACO-RBFNN的PID控制器可以得到令人满意的控制效果,可以应用于工业自动化控制系统的PID控制器参数优化。     

模糊PID控制器在穿梭车控制系统的应用

针对传统PID控制器参数整定不良、适应性差、控制精度不理想的现状,提出了动态过程中参数自适应的模糊PID控制系统.根据穿梭车所用直流伺服电机参数及穿梭车负载状况,建立穿梭车控制系统简化数学模型.使用Matab的Simulnk工具箱对穿梭车控制系统进行仿真研究.由仿真结果可知,采用自适应模糊PID控制器,控制系统调整时间变短,响应速度更快,具有较好的鲁棒特性.利用仿真得出的模糊控制规则表于穿梭车控制系统中进行在线PID自整定,应用表明,使用自适应模糊PID控制器可有效减小超调量,加快控制系统的调整时间,达到了良好的实际控制效果.仿真与实验结果表明自适应模糊PID控制器具有动态响应快、超调量小和抗干扰能力强等优点,是一种更加有效的控制策略.     

PID控制器参数优化算法的仿真研究

研究PID控制器参数优化问题,现代控制对象具有复杂非线性、时变性特点,引起系统的输出品质特性差,超调大稳定性时间长,控制精度差等.传统PID控制是针对线性控制系统提出的,控制精度比较低.为了提高PID控制精度,基于神经网络提出PID控制器参数自适应优化方法.通过将系统控制偏差和PID控制器的3个参数作为神经网络的输入,最优控制性能作为优化目标,通过神经网络自身学习和加权系数调整,获得最优控制性能的PID控制器参数.仿真结果表明,神经网络的PID控制方法提高了系统控制精度,系统响应速度更快,具有很强的自适应性和鲁棒性,为优化控制系统提供了参考.     

参数模糊自整定PID控制器在皮革收缩温度测定仪中的应用

针对皮革收缩温度测定仪的温度控制系统提出了一种参数模糊自整定PID控制方法,该方法集中了模糊控制和常规PID控制两种控制的优点.在重点介绍了模糊PID控制器的设计方法基础上,并利用MATLAB软件分别进行了参数模糊自整定PID控制系统和常规PID控制系统的仿真实验.仿真实验结果表明,参数模糊自整定PID控制方法使皮革收缩温度测定仪的温控系统的性能得到很大的改善.     

中央空调房间温度智能PID控制的仿真研究

中央空调房间温度控制系统是一个复杂系统,针对一次性整定得到的PID参数难以保证系统控制始终处于优化状态和良好的品质特性,提出了参数自整定方法,通过实时改变PID参数从而保证控制系统的优良品质。结合粒子群优化算法和模糊控制以及传统PID控制各自的优势,设计了一种新的自适应模糊PID控制器。鉴于PID控制器的性能完全依赖于其参数的整定和优化,采用粒子群算法离线优化PID参数,并利用模糊控制在线调整PID参数,以取得良好的控制效果。利用Matlab软件进行了数字仿真。仿真结果表明,方法调节精度较高,调节迅速,超调小,具有一定的可行性。     

基于BP网络的船舶动力定位控制技术仿真研究

在船舶动力定位控制优化问题的研究中,为了解决第一代动力定位系统中PID控制器参数整定困难的缺点,提高动力定位的实时性、稳定性和可靠性,提出了将BP网络与PID控制器相结合的控制策略,使系统具有PID控制器简单可靠等优点及BP网络的自学习和自适应能力等特性.采用三层BP网络,根据梯度最速下降法,不断修正各层神经元之间的连接权值,在线调整PID控制器参数,得到满足定位要求的最佳参数组合,提高系统的快速性和定位精度.最后以某动力定位船为研究对象,在MATLAB平台上对控制器进行定位功能的仿真验证,仿真结果表明所设计的控制器具有较好的控制性能.     

Research on Fuzzy Self Adaptive PID Controller with Parameters Tuning

主要研究了模糊自适应PID控制器参数整定方法,给出了预估计PID参数值的经验公式和方法.用MATLAB软件对PID控制、模糊自适应PID控制的控制性能分别进行了仿真研究,结果表明参数模糊自整定PID控制具有良好的稳态精度和自适应能力.     

自平衡机器人变论域模糊PID控制研究

针对两轮自平衡机器人的动态平衡控制问题,提出了一种可变论域模糊PID控制算法,对机器人体的倾斜角度设计了二级模糊控制器.由第一级模糊控制器利用论域伸缩因子来动态改变第二级模糊控制器的论域,实现了论域随自平衡控制系统要求进行自适应伸缩,能较好地解决自平衡系统控制规则数量与控制精度间的矛盾.仿真结果表明,变论域控制方法动态特性明显优于常规模糊PID控制,使机器人的平衡控制系统具有自适应能力强,实时控制性能好的特点.     

基于MATLAB的模糊自适应控制器的仿真

提出了一种参数自适应模糊PID控制器,将模糊控制器和PID控制器结合在一起,利用模糊逻辑控制,并把MATLAB中的Fuzzy Toolbox和SIMULINK有机结合起来,实现了PID控制器参数在线自调整。进一步完善了PID控制器的性能,提高了系统的控制精度。仿真表明算法的有效性。可以看出SIMULINK是控制系统动态仿真的有力工具,而且相对于以往任何一种仿真方法,MATLAB语言更方便、高效,具有无可比拟的优越性。     

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.