小型电加热反应器温度的模糊自适应整定PID控制

小型电加热反应器系统具有较大的纯滞后、惯性滞后、非线性和时变特性,参数固定不变的普通PID控制器难以进行精确温控.通过把操作人员积累的PID参数整定经验知识总结成模糊规则,利用模糊逻辑推理进行在线实时整定,设计了电加热反应器温度模糊自适应整定PID控制算法.通过Matlab与组态软件"组态王"KINGVIEW的动态数据交换,在Matlalb上编程实现了模糊自适应整定PID控制算法.进行了一般情况下和具有较强非线性和时变特性情况下温度控制实验,实验结果表明,模糊自适应整定PID控制取得了比普通PID更好的控制结果,模糊自适应整定PID控制对过程非线性和时变特性具有更强的适应性.     

基于Matlab参数自整定PID控制器的设计与仿真

本文针对常规PID控制器不能在线进行参数自整定的问题,结合模糊控制技术,提出了一种模糊自整定PID参数的方法,并利用Matlab的模糊控制工具箱以及Simulink对其进行了仿真,结果表明设计的自整定PID模糊控制器具有控制精度高,超调小,动态性能好的特性.     

PID参数整定法的仿真

PID调节器的控制品质,主要取决于调节器的参数整定.计算量大是用理论计算方法整定PID调节器参数要解决的难题之一.针对PID调节器参数整定过程中计算复杂、计算量大的问题,提出了一种基于Matlab的调节器参数衰减频率特性整定法.该方法以Matlab为工具,将理论计算与仿真分析结合起来,根据控制要求计算并绘制出控制器整定参数关系曲线,对计算结果进行仿真,分析整定参数在解平面上变化时闭环系统的响应,从而确定出最佳的调节器整定参数.结果表明,对于不同的被控对象参数或不同的整定要求,该方法都能方便地求得最佳的调节器整定参数,使得采用理论计算法整定调节器参数具有了工程实用价值.     

极点配置和状态观测器辅助设计工具开发

开发了一个运行于MATLAB环境的极点配置和状态观测器设计GUI辅助工具,帮助设计人员快捷、直观地完成相应的系统设计与仿真任务.在论述有关理论的基础上,以Matlab GUIDE为开发手段,进行该GUI辅助工具的设计.该设计的图形用户界面由GUIDE中的控件编辑、组合而成,控制算法通过调用Control System Toolbox中的命令函数来实现,为了实现不同控件callback subfunction代码之间的数据传输,采用global将要求共享的变量申明为全局变量.该GUI辅助工具可以做为Matlab SISO Design Tool 的有益补充.     

基于S函数的模糊整定PID控制器的设计及仿真

针对工业过程控制中被控对象往往为非线性、时变系统,常规的PID控制对于这样的系统的控制效果不是很理想,提出了模糊整定PID控制算法,并且在Matlab下利用S函数实现了模糊整定PID控制器的设计及仿真,并将该方法用于激光晶体生长系统的直径调节器中,结果表明,该系统对纯滞后、参数时变的激光晶体生长系统有很好的控制作用.     

智能PID参数自整定技术在伺服系统中的应用

针对常规PID控制参数整定困难,且受时变、非线性等因素影响而不能达到预期控制效果的实际情况,提出了RBF网络动态辨识的BP神经网络PID参数自整定算法.此算法可实现PID控制参数的在线自整定和优化;同时,将算法应用于伺服控制系统中,以VC++6.0和Matlab为开发和仿真工具,对动态辨识神经网络智能PID参数自整定方法进行仿真研究.仿真结果表明,控制算法鲁棒性强、响应速度快,可用于控制参数时变的非线性系统.     

一种PID多指标优化设计方法及实现

关于控制器优化设计问题,常规的PID参数整定方法大多只适用于满足经验公式条件的对象,整定目标往往针对某一特定指标。为了兼顾系统的多个性能指标,提出了一种多指标约束下的PID参数优化整定方法:将动态性能指标作为优化目标,系统极点位置作为约束条件,采用Matlab仿真计算求解,并阐述了利用COM组件技术实现VB与Matlab混合编程的关键步骤,将其应用到PID多指标优化设计中完成了程序实现,并以实例进行了仿真计算,仿真结果证明了所提方法的有效性以及程序的实用性。     

电动缸测控系统的仿真与通信

为了研究电动缸的性能和控制系统,利用虚拟仪器LabWindows/CVI设计了电动缸测控系统的仿真软件.通过对电动缸数学建模,并模拟电动缸伺服驱动器的位置信号,采用增量式PID、步进式PID及专家PID控制算法对控制效果进行仿真.为了使控制效果达到最佳,采用遗传算法对PID参数进行整定,结合Matlab/GUI实现在线参数整定,并通过Polling Queue技术实现数据的通信.仿真结果表明,该仿真软件达到了较好的控制效果.     

参数自整定模糊PID控制器在转矩流变仪系统的应用研究

在参数自整定模糊PID控制器的基础上,利用模糊推理的方法实现了对PID参数的在线自动整定,并且将该控制软件在转矩流变仪中的应用进行了研究,实验结果表明,参数自整定模糊PID控制能使系统达到满意的控制效果,对进一步应用研究具有较大的参考价值.     

SR电机模糊自整定PID控制器设计与仿真

针对开关磁阻电机的非线性、时变和强耦合性,提出了模糊自整定PID的调速控制策略.在分析SR电机非线性数学模型的基础上,将速度偏差和偏差变化率作为控制器输入,PID的三个控制参数为输出.利用模糊规则对PID参数进行在线修改,实现PID参数的自动最佳调整.通过将MATLAB中的Fuzzy Toolbox和SIMULINK有机结合,实现了基于模糊自整定PID控制器的开关磁阻电机调速系统仿真,并进行了传统PID控制与模糊自整定PID控制的仿真比较.结果表明:模糊自整定PID控制器能够明显改善系统的调速性能,具有较强的鲁棒性,并且计算量少,易于实现,便于工程应用.     

一个扩展的CCS

诉微分算子ＣＣＳ（Ｃａｌｃｌｕｓ ｏｆ Ｃｏｍｍｕｎｉ－ｃａｔｉｎｇ Ｓｙｓｔｅｍｓ）是由英国爱丁堡大学计算机科学系的ＲｏｂｉｎＭｉｌｎｅｒ首先提出的。ＣＣＳ是一个在数学上完整的理论算子系统,可以作为计算机通讯系统的基本理论模型。我们先简要说明一个ＣＣＳ的内容。我们所作的工作是在理论上扩充地的ＣＣＳ,使得我们的ＣＣＳ更为一般化。在我们的观战看来,ＲｏｂｉｎＭｉｂｅｒ的ＣＣＳ只不过是我们的ＣＣＳ的一     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

An Analysis of the Criteria for Evaluating Adequate Theories of Computation

This paper deals with the question: What are the criteria that an adequate theory of computation has to meet? (1) Smith’s answer: it has to meet the empirical criterion (i.e. doing justice to computational practice), the conceptual criterion (i.e. explaining all the underlying concepts) and the cognitive criterion (i.e. providing solid grounds for computationalism). (2) Piccinini’s answer: it has to meet the objectivity criterion (i.e. identifying computation as a matter of fact), the explanation criterion (i.e. explaining the computer’s behaviour), the right things compute criterion, the miscomputation criterion (i.e. accounting for malfunctions), the taxonomy criterion (i.e. distinguishing between different classes of computers) and the empirical criterion. (3) Von Neumann’s answer: it has to meet the precision and reliability of computers criterion, the single error criterion (i.e. addressing the impacts of errors) and the distinction between analogue and digital computers criterion. (4) “Everything” computes answer: it has to meet the implementation theory criterion by properly explaining the notion of implementation.     

FTDSS：高容错分布式共享存储机制

Computerized data has become critical to the survival of an enterprise. Company must have a strategy for recovering their data should data lose. RAID is a popular mechanism to offer good fault-tolerance. But RAID can notwork well when one more disks fail. In this paper, we present an efficient Network-based high High-Tolerance Dis-tributed Shared Storage mechanism called FTDSS. FTDSS makes use of disk space of node in Network to build alarge pubhc shared storage space. Users can read/write their file from/to the public storage space from node of net-work. Physically File is stored in each node in form of data fragment or XOR verify fragment. Because of redundant XOR fragments, file is available even when two more nodes fail. FTDSS realize distant redundant srorage. At last,this paper use experiment to prove that FTDSS can offer high. fault-tolerance and advanced performance.     

Existential foundations of the composition paradigm

The theses of existonness, compoundness, and polyadness are proved. The consistency of these theses with the reversibility principle is founded. Existential foundations of the composition paradigm are constructed. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 3–12, March–April 2008.     

一种面向查询的多文档摘要方法

面向查询的多文档摘要技术有两个难点 第一,为了保证摘要与查询密切相关,容易造成摘要内容重复,不够全面;第二,原始查询难以完整描述查询意图,需进行查询扩展,而现有查询扩展方法多依赖于外部语义资源。针对以上问题,该文提出一种面向查询的多文档摘要方法,利用主题分析技术识别出当前主题下的子主题,综合考虑句子所在的子主题与查询的相关度以及子主题的重要度两方面因素来选择摘要句,并根据词语在子主题之间的共现信息,在不使用任何外部知识的情况下,进行查询扩展。在DUC2006评测语料上的实验结果表明,与Baseline系统相比,该系统取得了更高的ROUGE评价值,基于子主题的查询扩展方法则进一步提高了摘要的质量。     

Autonomous programmable DNA nanorobotic devices using DNAzymes

A major challenge in nanoscience is the design of synthetic molecular devices that run autonomously (that is, without externally mediated changes per work-cycle) and are programmable (that is, their behavior can be modified without complete redesign of the device). DNA-based synthetic molecular devices have the advantage of being relatively simple to design and engineer, due to the predictable secondary structure of DNA nanostructures and the well-established biochemistry used to manipulate DNA nanostructures. However, ideally we would like to minimize the use of protein enzymes in the design of a DNA-based synthetic molecular device. We present the design of a class of DNA-based molecular devices using DNAzyme. These DNAzyme-based devices are autonomous, programmable, and further require no protein enzymes. The basic principle involved is inspired by a simple but ingenious molecular device due to Tian et al. [Y. Tian, Y. He, Y. Chen, P. Yin, C. Mao, A DNAzyme that walks processively and autonomously along a one-dimensional track, Angew. Chem. Intl. Ed. 44 (2005) 4355–4358] that used DNAzyme to traverse on a DNA nanostructure, but was not programmable in the sense defined above (it did not execute computations).     

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.     

基于LDA话题演化研究方法综述

现实生活中不断有新话题的产生和旧话题的衰减,同时话题的内容也会随着时间发生变化。自动探测话题随时间的演化越来越受到人们的关注。Latent Dirichlet Allocation模型是近年提出的概率话题模型,已经在话题演化领域得到较为广泛的应用。该文提出了话题演化的两个方面 内容演化和强度演化,总结了基于LDA话题模型的话题演化方法,根据引入时间的不同方式将目前的研究方法分为三类 将时间信息结合到LDA模型、对文本集合后离散和先离散方法。在详细叙述这三种方法的基础上,针对时间粒度、是否在线等多个特征进行了对比,并且简要描述了目前广泛应用的话题演化评测方法。文章最后分析了目前存在的挑战,并且对该研究方向进行了展望。     

A method of defuzzification based on the approach of areas' ratio

The new method of defuzzification of output parameters from the base of fuzzy rules for a Mamdani fuzzy controller is given in the paper. The peculiarity of the method is the usage of the universal equation for the area computation of the geometric shapes. During the realization of fuzzy inference linguistic terms, the structure changes from the triangular into a trapezoidal shape. That is why the universal equation is used. The method is limited and can be used only for the triangular and trapezoidal membership functions. Gaussian functions can also be used while modifying the proposed method. Traditional defuzzification models such as Middle of Maxima − MoM, First of Maxima − FoM, Last of Maxima − LoM, First of Suppport − FoS, Last of Support − LoS, Middle of Support − MoS, Center of Sums − CoS, Model of Height − MoH have a number of systematic errors: curse of dimensionality, partition of unity condition and absence of additivity. The above-mentioned methods can be seen as Center of Gravity − CoG, which has the same errors. These errors lead to the fact that accuracy of fuzzy systems decreases, because during the training root mean square error increases. One of the reasons that provokes the errors is that some of the activated fuzzy rules are excluded from the fuzzy inference. It is also possible to increase the accuracy of the fuzzy system through properties of continuity. The proposed method guarantees fulfilling of the property of continuity, as the intersection point of the adjustment linguistic terms equals 0.5 when a parametrized membership function is used. The causes of errors and a way to delete them are reviewed in the paper. The proposed method excludes errors which are inherent to the traditional and non- traditional models of defuzzification. Comparative analysis of the proposed method of defuzzification with traditional and non-traditional models shows its effectiveness.