智能电动执行机构

由西安自动化仪表二厂与西北工业大学联合研制的智能电动执行机构有角行程和直行程两种,它可与 DDZ-Ⅱ、Ⅲ型电动单元组合仪表中的变送单元、调节单元等配套,构成各种控制系统,自动操纵风门、档板、阀门等机械设备,以实现自动调节的目的。该产品已通过鉴定,批量生产。1 工作原理智能电动执行机构由智能伺服放大器,数显式电动操作器,带位置发送器的执行机构组成,其原理框图如下所示。     

智能多转式电动阀门执行机构控制系统设计

本文详细阐述了一种多转式阀门电动执行机构智能控制系统的工作原理、硬件构成和软件设计。该控制系统采用Freescal。公司的16位微处理器作为中央控制单元，完成了一个集远程自动、手动控制，现场手动调节，信号检测，故障指示及人机交互接口等功能干一体的智能阀门控制系统。     

"DDZ-S系列电动执行机构”讲座——第3讲 ZPE-2032型电动伺服放大器

电动伺服放大器是电动执行器的辅助单元,和执行机构配套可组成比例式电动执行机构。它的功能相当于气动执行器中的阀门定位器。所以,一些西欧国家又把电动伺服放大器称为电动阀门定位器。 电动伺服放大器在比例式电动执行机构系统中（见图１）主要有二大功能：①将调节器输入信号和位置反馈信号进行综合比较,并将其偏差进行放大;②作为驱动伺服电机的功率放大级,以足够的功率去驱动伺服电机旋转。 ＺＰＥ－２０３２型电动伺服放大器是专门为ＤＤＺ－Ｓ型电动执行机构配套而设计的新产品,也可以作为一个通用单元应用于其它类型的电动执…     

数字化阀门电动执行机构

论述了阀门电动执行机构的数字化控制器的设计与开发,应用数字信号处理器（DSP）作为控制系统的核心,采用智能功率模块（IPM）作为功率器件,控制策略采用直接转矩控制算法,给出了硬件和软件的选用和设计原则以及控制系统的流程图。     

基于PLC与HMI控制的电动执行机构转矩调试系统

针对国内阀门电动执行机构调试系统精度差、功能的不完善状况,开发一套基于PLC和HMI控制的电动执行机构调试系统。建立了一套以PLC为中枢控制模块的完善控制结构体系,重点阐述系统的程序控制流程、信号滤波处理,并给出详细的程序设计过程。     

"DDZ-S系列电动执行机构"讲座第1讲 DDZ-S系列电动执行机构总体技术要求

电动执行机构是自动控制系统的重要终端控制元件。它以电源为动力,接收标准信号（包括模拟量、数字量）,将此信号转变成对应的机械位移（转角、直线或多转）来操作调节阀、风门挡板等调节机构完成自动调节任务。所以,它对整个自动控制系统的安全运行,可靠性及调节品质的优劣都有很大影响。 我国在５０年代中期就开始研制和生产电动执行机构,当时主要是仿制产品;６０年代初开始研制ＤＤＺ－Ⅰ型电动单元组合仪表电动执行机构,６０年代末开始研制 ＤＤＺ－Ⅱ型电动单元组合仪表电动执行机构;７０年代中期开始研制ＤＤＺ－Ⅲ型电动单元…     

"DDZ-S系列电动执行机构"讲座第2讲 DDZ-S系列电动操作器

１概述 电动操作器（又称Ｄ型操作器）是ＤＤＺ－Ｓ系列仪表的辅助单元,它与ＤＤＺ－Ｓ系列电动执行机构配套使用,是实现“人机对话”的必备设备。在自动控制系统中,电动操作器具有远距离直接操作电动执行机构、手动一自动双向无扰动切换、阀门位置显示和一些保护与联锁功能。 当调节仪表（或上位控制仪表）失效时,电动操作器能自动切换到手动状态,操纵人员可直接操纵阀门位置,保证生产过程的安全进行。 通常电动操作器都由电动执行机构生产厂家配套供应。２电动操作器通用技术要求２．１接收统一连接信号 阀位信号：４～２０ｍＡ,ｄ…     

智能变频电动执行机构的设计与实现

智能变频电动执行机构控制系统采用的控制器集成BLDC电机驱动,具有智能变频型电动执行器所有功能要求.取得了电动执行器在变频技术和智能技术的全面突破.作为工业控制的核心单元,可极大地提高控制系统的性能及可靠性,被广泛应用在各行业工业控制系统中.本文重点介绍整个智能变频控制系统的软硬件设计与实现.     

基于CANopen协议的电动执行机构设计

针对常规型电动执行机构的现场接线方式存在着布线工作量大、操作维护困难、可靠性不高、网络通信能力差等方面的问题,提出了一种基于CANopen协议的总线型电动执行机构设计方案.在简要介绍电动执行机构架构的基础上,首先给出了电动执行机构控制器的硬件设计方法,其中主要介绍了电动执行机构控制单元电路和CAN总线通讯接口电路的设计;接着给出了软件设计的思路,重点介绍了对象字典的设计及CANopen通讯程序的设计,针对通讯程序设计中的难点,提出了一种基于队列方式的报文处理模式.最后,在实际工程中成功地应用了所提出的设计方案,应用结果表明这种总线型电动执行机构具有智能化、信息化、数字化等特点,能够满足工业控制系统的网络化发展需求.     

基于TMS320F2812的智能电动执行器控制系统设计

给出一种基于TMS320F2812的智能电动执行器控制系统设计方案。设计了控制系统硬件电路,并给出了软件设计方法,提出了直流无刷电机速度调节和阀门位置控制独立控制的策略。初步实验结果表明：所提出的控制策略能够使阀门平稳、可靠的运行,实现了阀门位置的精确控制。     

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.