现代控制理论在电厂中央空调系统中的应用研究

本课题针对电厂2X600MW机组电厂中央空调系统的典型子系统一电子设备间空调系统为研究对象,采用现代控制理论模糊关系辨识方法,建立了电子设备间温度控制系统的模糊模型。设计了它的模糊控制器,综合模糊控制和传统PID控制的优劣,提出了一种电子设备间温度控制采用模糊一PID的控制方案。     

变风量空调系统房间温度控制研究

在变风量空调温度控制系统研究中,空调系统本身存在的多变量、时变性、干扰大等问题,传统算法很难起到很好的控制效果.针对传统控制算法的缺陷和控制上的难点,提出变论域思想在变风量空调温度控制系统上的应用.应用种在传统模糊PID控制的基础上,引入变论域思想,设计了一种变论域模糊PID算法的控制器.最后将模糊PID控制算法和变论...     

模糊PID复合控制在变频空调中应用研究

空调房间温度控制是一复杂的控制过程,传统的模糊或PID控制很难得到较好的控制效果,模糊控制和PID控制适当结合控制空调房间温度可使控制效果大大提高。本文建立了房间温度控制模型,介绍了模糊和PID控制并联结合方式并对各复合控制器进行了设计。对设计的变频空调控制系统进行了仿真,结合仿真图,从鲁棒性和稳定性方面分析了设计的各模糊和PID复合控制器控制效果。     

基于群智能优化算法与MATLAB仿真的高温炉模糊PID温度控制系统设计

针对高炉燃烧器温度控制问题,提出一种PSO-模糊PID的温度控制方法。首先,对模糊PID控制方法进行了研究与探讨;然后,在模糊PID控制方法的基础上,引入粒子群优化算法对PID参数进行优化;最后通过对比实验验证提出方法的有效性与可行性。测试结果表明：粒子群优化算法能够对模糊PID控制系统进行优化,且经过粒子群优化算法优化后的模糊PID控制系统进入稳态所需的时间大大减少,超调幅度达到最低,且在整个控制过程中没有出现震荡情况。可知设计温度控制方法具有可行性和有效性,且响应速度快、稳定性高,能够实现提高温度控制系统自适应能力的目的,继而实现对高炉燃烧器温度进行调节与控制。     

基于模糊PID大型电力机组温度过热控制

随着高精密技术的发展,高精度、超高精度的温控系统越来越多被人们运用于大型电力机组中。传统的温度控制系统对各异的真实系统适配性较差,不能保证系统性能,适应性较差。针对这些问题,提出了一种模糊自适应PID大型电力机组温度过热控制算法,即专家-模糊PID控制器方法,根据温度偏差选择采用专家控制还是模糊PID控制,克服适应性差的问题。用专家控制避免设定值震荡,并通过模糊PID温度控制较快达到设定初始目标温度值,并稳定在该值上。最后通过仿真实验证明这种模糊PID超精度温度控制系统对于大型电力机组的温度过热控制问题具有控制精度高、响应速度快、温度波动小等优点。     

冰淇淋老化机温度控制系统的设计

针对在冰淇淋均质老化机的温度控制系统中,传统PID控制方法表现不佳的问题,提出了分段式模糊PID的控制方法.根据温度误差对系统控制区进行分段,通过分段控制的模糊控制方法和PID控制结合在一起,实现了两种控制方法优势互补.设计了基于单片机的温度控制器,实验结果表明,系统的响应速度和稳态精度都得到了提高,该方法优于传统PID控制方式.     

基于PLC的模糊控制在温度控制中的应用研究

为提高传统温度控制系统的稳定性、安全性和控制精度,设计一个基于PLC的智能化换热机组PID模糊系统。首先,对PID模糊控制和smith预估控制原理进行详细介绍;然后再对智能化换热机组进行整体结构设计,重点对温度控制进行设计;之后分别对该系统的PLC结构、系统硬件部分以及软件部分进行具体设计。最后,为验证设计的系统是否可行,将对该系统进行仿真实验,通过各参数设置后进行系统机组测试。测试结果表明,系统运行效果较好,温度控制准确度有所提高,具备安全性和稳定性,满足温度控制要求。     

基于自适应模糊PID控制器的温度控制系统

针对温度控制系统非线性、大滞后、时变性等特征和对温度控制的要求,采用了自适应模糊PID控制器来实现温度控制,给出了C8051F020 Soc单片机控制实现的具体方案.仿真和实验结果表明了该系统的控制效果优于常规PID控制器,满足温度控制系统实时性和精度的要求.     

基于PLC的发酵罐温度控制系统

针对发酵罐的温度控制特点,采用西门子PLC 226设计了发酵罐温度控制系统。由于进水阀采用双位阀,为了便于PLC 226实现,设计了一种基于模糊PID思想的智能控制器。该控制器按照模糊PID思想,但实现过程与模糊PID完全不同。本系统已在山西卫氏鱼康实业有限公司投入使用,经实际运行该控制系统能完全满足发酵罐的温度要求。     

生物发酵过程温度模糊PID控制系统的研究

针时生物发酵过程温度控制的非线性和时变性的特点,设计了一种基于模糊PID的温度控制系统.采用偏差和偏差变化率的变化规律为依据,查询模糊规则表生成控制规则,对发酵过程中难以整定的PID参数进行在线调节.将模糊PID控制算法应用于ε-聚赖氨酸发酵监控系统,对发酵罐的温度进行实时检测控制.通过实验验证了模糊PID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.