VAV空调系统末端解耦控制研究

通过对VAV变风量空调系统的两个末端控制回路之间的耦合进行分析,运用最小二乘法建立被控对象＂送风量—室内温度＂控制回路的数学模型。针对被控对象的特性,采用前馈补偿解耦方法设计解耦网络,并设计单神经元自适应PID控制器。最后,通过MATLAB仿真,证明了所设计的解耦网络和控制器是行之有效的。     

多变量发酵过程的神经网络在线解耦控制

为提高多变量系统解耦控制的性能,提出了一种基于参考模型的神经网络在线解耦控制方法.构造神经网络实现前馈解耦,通过参考模型的输出与被控系统输出估计耦合作用对被控量的影响,由此设计神经网络权值参数学习算法,在线调整网络参数使多变量耦合系统实现解耦;对解耦后的子系统分别设计闭环控制器,以达到优良的控制性能.仿真实验结果表明,提出的解耦控制方法是简单有效的.     

变风量空调系统恒温解耦控制优化

在室内恒温控制问题的研究中,变风量空调系统的房间送风量、冷冻水流量和风机转速三个输入变量与房间温度、送风温度和静压三个输出变量之间存在着不同程度的耦合关系,每个房间的温度控制会受到不同程度的干扰,严重时会影响到整个系统的稳定性.为解决上述问题,根据变风量空调系统的房间、表冷器、风机等各个子系统模型,通过寻找一个合适的开环传递函数矩阵,实现对系统的解耦控制,通过使解耦矩阵的对角元素为1,得到简化的解耦矩阵.比通常利用对角化方法和状态反馈矩阵方法直接求得的解耦矩阵要简单.运行空调实验结果表明控制回路之间干扰不明显,解耦控制效果良好.     

多变量解耦控制系统设计与仿真

工业生产过程中,被控系统越来越复杂,需要控制的变量通常不止一对,而且相互耦合,较成熟的线性多变量控制理论与设计方法已难以满足实际的多变量生产过程控制。本文针对多变量强耦合带有延迟环节的被控系统,研究了一种简化的串联前馈补偿解耦控制器设计方法。根据被控对象的辨识模型,设计串联前馈补偿解耦器,使系统解耦成单输入单输出模型,进而分别对解耦后输入输出模型设计PID控制器,整定PID控制器参数。仿真结果表明该方法具有较好的解耦能力和鲁棒性,算法简单,易于实现。     

多变量解耦控制系统设计与仿真北大核心CSCD

工业生产过程中,被控系统越来越复杂,需要控制的变量通常不止一对,而且相互耦合,较成熟的线性多变量控制理论与设计方法已难以满足实际的多变量生产过程控制。本文针对多变量强耦合带有延迟环节的被控系统,研究了一种简化的串联前馈补偿解耦控制器设计方法。根据被控对象的辨识模型,设计串联前馈补偿解耦器,使系统解耦成单输入单输出模型,进而分别对解耦后输入输出模型设计PID控制器,整定PID控制器参数。仿真结果表明该方法具有较好的解耦能力和鲁棒性,算法简单,易于实现。     

基于ESO的动态解耦方法及其应用仿真*

针对多变量系统控制中的耦合问题,提出了一种基于扩张状态观测器（ESO）的动态解耦方法。该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估计该总扰动并反馈到控制器进行补偿,从而实现动态解耦;对解耦后的每个子系统,分别设计出了基于误差最小二乘指标的神经元自适应PID（NAPID）控制器。该方法简化了解耦过程,放松了对系统模型的要求,计算量小、鲁棒性强。最后用该法对蒸馏塔进行控制仿真,仿真时使用混沌优化方法对ESO的参数进行了离线优化,并给出了与模糊PID解耦控制方法对比的     

双容神经网络解耦控制的在线实现

主要进行基于神经网络的解耦控制研究.针对罗克韦尔实验室中的双容液位对象强耦合的特点,将模糊自适应PID算法控制和神经网络引入控制系统的设计中.提出一种神经网络在线解耦算法并用神经网络对双容液位系统进行建模.将该算法用于双溶液位控制系统的设计中,用来实现对被控对象的解耦控制.通过对设计方案的仿真研究和现场实时控制,结果表明:该设计方案具有良好的解耦效果;控制系统的调节品质令人满意.     

解析解耦设计在变风量空调系统中的应用

研究空调优化控制问题,变风量空调(VAV)具有多变量、强耦合和非线性系统.变量之间的耦合会直接影响空调系统的性能指标和稳定性.针对变风量空调系统进行建模,模型为三输入三输出的传递函数矩阵.在内模控制系统结构基础上,运用解耦控制的解析设计方法来设计解耦控制器.解耦设计方法可以达到标称系统变量间完全解耦,并且参数可以在线调整,使输出能够紧密跟随系统的动态变化.仿真结果表明,解耦控制器的设计提高了性能,应用效果较好.     

环境试验室热工系统规则自提取模糊控制仿真

以某环境试验室室内温度、送风系统和热水系统多回路在线控制为背景, 针对其存在的多参数、大滞后、非线性等控制难题, 讨论了各个回路热工特性传递函数建立和自组织模糊控制仿真问题. 首先, 提出了规则自提取模糊控制(self-abstracting rules fuzzy control, SARFC)方法. 然后, 根据各被控回路的动态热工特性和参数辨识要求, 试验研究了各回路的动态响应特性, 完成了各回路传递函数模型参数的辨识, 得到了各回路的传递函数模型. 最后, 采用SARFC方法, 仿真研究了基于送风系统调节和热水系统调节的环境试验室温度模糊控制仿真, 得到了较好的控制仿真效果, 为进一步试验研究环境试验室热工系统模糊控制提供了理论基础.     

VAV系统送风管道静压神经元网络控制的仿真研究

变风量(variable air volume，VAV)空调系统中送风管道静压的控制效果直接决定了VAV系统的稳定性和节能能力。但送风管道静压的强耦合特性往往使得其控制效果很不理想。针对这种情况，该文利用了神经元网络具有自学习以及超强非线性逼近的能力，提出了基于线性神经元网络的补偿控制方法。这种控制方法能够在线学习，根据送风管道静压耦合因素的变化自适应的调节控制量，实现对管道静压的补偿控制。文中给出了神经元权系数的在线学习公式，建立了被控对象数学模型，并通过Matlab仿真验证了控制算法的有效性。     

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。     

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。