基于遗传算法寻优的PID控制技术及应用

以船舶减摇鳍系统为研究对象,提出一种基于遗传算法寻优的PID控制算法,并进行了计算机仿真和试验研究。结果表明,根据遗传算法寻优设计的PID控制器具有较强的鲁棒性,即使在外部环境恶劣的条件下,系统的控制性能仍具有较好的动态品质和稳态精度。     

开关磁阻电机单神经元自适应PID控制系统

在开关磁阻电机（SRM）调速系统中,转速闭环是必不可少的,传统的转速控制采用PID调节器,但是可靠性不高、参数整定不良、性能欠佳.针对以上问题,本文采用单神经元与PID相结合代替传统的PID调节器,在Matlab/Simulink仿真平台中建立了仿真模型.仿真结果表明,该方法不但结构简单,而且稳定性好,有较强的鲁棒性.     

柴油机自适应遗传非线性PID调速控制仿真

研究船用柴油机控制优化问题,柴油机调速要求快、稳、准。针对船用柴油机调速系统的时变、非线性及外界干扰等特点,传统PID调速稳定时间长,控制效果不佳。为提高喷油量达到控制准确度,改善调速系统性能,提出了一种柴油机自适应遗传非线性PID调速控制策略。采用Matlab对柴油机调速系统模型进行辨识并验证其准确性。利用非线性PID控制实现各参数增益的实时调整,提高了抗干扰能力,通过自适应遗传算法对系统的动态偏差进行监控,优化非线性PID控制器参数,减少了超调量,提高控制精度。仿真结果表明,采用自适应遗传非线性PID控制器稳定时间更短,鲁棒性强,控制精度更高,优化了柴油机调速系统性能。     

基于微粒群优化算法的二自由度PID调节器的设计

提出了一种新二自由度PID调节器的设计方法。基于灵敏度函数,采用PSO优化算法对二自由度PID参数进行自适应调整,仿真结果和改进的遗传算法进行比较,系统同时具有良好的跟随性能和抗干扰能力,所设计的二自由度调节器具有很强的鲁棒性,证明了PSO算法的有效性。     

基于3D激光扫描系统的模糊自整定PID控制的研究

针对3D激光扫描系统的特点,设计了以模糊自整定PID控制技术为基础的转速调节器,最后利用MATLAB分别对模糊自整定PID与常规PID控制的调速系统进行仿真分析与对比研究。仿真结果表明,与常规PID控制的调速系统相比,模糊自整定PID控制的调速系统调速性能更好,抗干扰能力更强,更适合应用于3D激光扫描系统。     

遗伟算法在PID控制器参数寻优中的应用研究

目的 用常规PID控制器对具有较大时间常数、大纯滞后特笥的被控对象实现最优控制。方法 采用遗传算法对PID参数进行寻优,在搜索空间内获得全局最优点。结果 将遗传算法和单纯形法分别用于PID参数寻优,仿真结果表明：采用遗传算法寻优能获得较好的控制效果。结论 在过程控制中,可采用遗传算法优化调节器参数。     

基于滑模变结构控制的EHA系统仿真研究

多电飞机功率电传作动系统,采用电能取代飞机能源系统中的液压能、气压能等二次能源.典型的功率电传作动系统主要有电静液作动器(EHA)和电机械作动器(EMA)两种.根据飞机系统运行特点,以EHA为研究对象,对其工作原理与结构特点进行分析,建立了EHA系统中驱动电机、液压泵、作动筒、活塞杆负载等的Simulink线性化仿真模型.同时,针对驱动电机控制精度低的问题,由于传统PID控制的EHA存在舵面控制精度差和频域带宽过窄等问题,故采用了滑模变机构控制对传统PID控制进行改善优化,并进行对比仿真.仿真结果表明,滑模变结构控制的EHA系统的控制质量得到了明显提高.     

基于改进遗传算法寻优的神经网络PID控制及应用

根据神经网络PID控制器初值的选取影响系统控制性能的特点,提出了一种基于改进遗传算法寻优的神经网络PID控制方法.即先利用遗传算法对PID控制器参数离线寻优,将求出的参数值作为控制器的比例、积分、微分系数的初值,再进行神经网络PID控制.对一类液位过程的实时控制结果表明采用本方法的控制系统具有较好的稳定性和鲁棒性.     

CMAC-PID在柴油机调速系统中的应用

研究柴油机优化控制问题,柴油机调速控制要求快速、准确.针对柴油机调速系统的非线性、时变等特点,导致稳定时间长,传统PID控制不理想.为了提高自动调节供油量,达到控制准确度,提出一种小脑模型神经网络(CMAC)与PID并行控制的柴油机调速系统(CMAC-PID).采用现代控制理论与经典相结合的方法对柴油机调速系统进行优化设计,利用传统PID来实现柴油机调速属于反馈控制,保证了系统的稳定性,并且能够抑制扰动,结合CMAC神经网络对控制器进行前馈控制,确保系统的控制响应速度,减小超调量,提高控制精度.仿真结果表明,采用CMAC-PID算法控制精度更高,超调小,稳定时间短,鲁棒性强,能优化柴油机调速系统性能,为设计提供了参考.     

基于遗传算法的LQG/LTR航空发动机性能优化

针对飞行控制系统控制器的设计中存在建模误差以及飞行过程中外界干扰的影响,采用LQG/LTR鲁棒控制方法完成某型战斗燃油机控制系统控制器的设计。为了提高战斗机控制精度,解决LQG/LTR鲁棒控制方法中存在的权矩阵Q和R选择困难的局限性,加入遗传算法,进行在线寻优。同时针对不同飞行条件下系统以及系统建模过程中造成的参数不确定性问题分别进行仿真,并与传统PID以及控制效果较好的基于遗传算法的PID控制进行对比仿真。理论研究和系统仿真结果表明,基于遗传算法的LQG/LTR控制系统与基于遗传算法的PID控制相比,不但具有良好的鲁棒性,而且响应快速,控制精度高,满足了战斗机飞行控制的要求。     

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     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

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。