具有预期闭环极点区域的稳定控制器的H∞优化设计方法

本文从工程应用角度出发,提出了一种将闭环极点设置于预期稳定区域的稳定控制器的 H∞优化设计方法,即实参数优化求解控制器的方法.这种方法综合考虑了闭环动态性能、抗 干扰、鲁棒性以及控制器本身的稳定性.实例表明,与现有的H∞设计方法相比,用本文方法 设计的控制系统在不显著增大抗干扰和鲁棒性指标情况下,具有闭环动态性能良好及控制器 稳定等优点,因此具有工程应用价值.     

H2最优控制器的不唯一性及闭环性能的改善

本文研究了H~2最优控制器的不唯一性问题,给出了H_2最优控制器集合存在的条件,并给出了一种将多变量H~2最优设计问题化为一组单变量的H~2最优设计问题的方法,给出了最优控制器集合的参数化公式,本文还给出了利用最优控制器集合中的自由参数提高闭环系统鲁棒性能及求取稳定最优控制器的方法。实例表明,这种设计方法可以充分利用控制器的自由度,实现提高系统鲁棒性以及求取稳定控制器的目的。     

鲁棒H-状态反馈控制

本文对结构参数不确定线性定常多变量系统的鲁棒Ｈ∞状态反馈设计问题进行了研究，给出了系统鲁棒稳定和干扰衰减的条件，及相应的鲁棒Ｈ∞状态反馈设计方法，并用这种方法设计了一个倒立摆平衡控制器。仿真结果表明，与ＬＱ设计方法相比，按本文所提出的设计方法得到的控制器具有鲁棒稳定能力强、闭环动态性能良好等优点。     

基于遗传算法的切换控制器设计与优化

利用遗传算法研究了一类切换规则只由状态决定的切换系统的控制器优化设计问题.首先由线性矩阵不等式(LMI)来设计切换控制器,然后应用遗传算法来对切换规则进行优化.优化后的切换规则不仅可保证闭环系统渐近稳定,而且具有良好的动态性能.将本文提出的方法应用在小车倒立摆控制系统上,仿真结果表明了本文设计方法的有效性.     

基于Backstepping设计的不确定非线性系统的预测控制

本文的目的是针对一类带有不确定性的单输入单输出的仿射非线性系统,设计一种非线性预测控制器.用反步设计思想获得具有待定参数的控制器表达式,然后用预测控制在线优化获得控制器的参数.用这种方法设计的控制器更易使闭环系统稳定,且闭环系统具有良好的动态特性.连续发酵过程的仿真结果也验证了控制器是有效的.     

基于LMI和IMC的动态反馈抗饱和补偿设计

提出了一种基于线性矩阵不等式(LMI)和内模控制(IMC)的动态反馈抗饱和补偿器的设计方法,为此首先简要地介绍了基于统一框架的抗饱和补偿器设计方法,然后针对原框架计算量庞大的问题,利用模型精确的IMC结构中对象和控制器同时稳定就能保证系统闭环稳定的特性对框架进行改造,并进一步选取了具有(?)2范数形式的性能优化指标,通过整定控制器的方法来优化闭环系统的工作性能,给出了LMI形式的结果．最后给出了运用此方法设计补偿器的一个仿真实例．     

不确定机器人的自适应神经网络控制与学习

针对具有未知动态的电驱动机器人,研究其自适应神经网络控制与学习问题.首先,设计了稳定的自适应神经网络控制器,径向基函数(RBF)神经网络被用来逼近电驱动机器人的未知闭环系统动态,并根据李雅普诺夫稳定性理论推导了神经网络权值更新律.在对回归轨迹实现跟踪控制的过程中,闭环系统内部信号的部分持续激励(PE)条件得到满足.随着PE条件的满足,设计的自适应神经网络控制器被证明在稳定的跟踪控制过程中实现了电驱动机器人未知闭环系统动态的准确逼近.接着,使用学过的知识设计了新颖的学习控制器,实现了闭环系统稳定、改进了控制性能.最后,通过数字仿真验证了所提控制方法的正确性和有效性.     

基于性能指标约束的一类输入死区非线性系统最优控制

针对一类考虑指定性能和带有输入死区约束的严格反馈非线性系统,本文提出了一种自适应模糊最优控制方法.采用模糊逻辑系统逼近系统的未知非线性函数及代价函数,利用backstepping方法及命令滤波技术,设计前馈控制器.针对仿射形式的误差系统,结合自适应动态规划技术,设计最优反馈控制器.采用指定性能控制方法,将系统跟踪误差约束在指定范围内.利用死区斜率信息解决具有死区输入的非线性系统的控制问题.基于Lyapunov稳定性理论,证明闭环系统内所有信号是一致最终有界的.最后仿真结果验证了本文方法的可行性和有效性.     

一类不确定性网络控制系统的滑模控制器设计

网络诱导时廷是影响网络控制系统稳定性和动态性能的主要因素．针对一类具有不确定性的网络控制系统,给出具有网络诱导时廷及不确定性的被控对象模型,设计其滑模控制器,建立基于滑模反馈控制器的网络控制系统闭环模型．通过Lyapunov方法证明,所得最大允许时延能够保证闭环网络控制系统稳定．仿真例子验证了该方法的正确性和有效性．     

基于广义无源的输入非仿射系统的H∞控制律设计

基于动态耗散的一般理论,提出了具有任意非线性输入端的非线性系统的一种新的控制器设计方法。该方法解决了以下两个问题：１）当系统严格广义无源时,设计非线性输出反馈使闭环系统稳定;２）当系统非广义严格无源时,设计同时具有状态反馈和输出反馈的双闭环控制器,使得闭环系统的内稳且具有Ｈ＾∞干扰衰减。对于线性系统,所设计的问题转化为对ＬＭＩ和ＡＲＥ的求解问题。     

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。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。