基于单片机通信网络的集散式电机同步控制系统设计

一种基于单片机通信网络的集散式电机同步控制系统.详细论述了构成控制系统的单片机环型通信网络、同步控制器、集中控制器的设计及工作原理.     

基于自由通信协议的多电机的同步控制

提出了利用自由通信协议,以PLC作为主站,通过RS-485总线与多台变频器串行通信构成的变频同步控制系统。介绍了系统的硬件构成,根据PLC与变频器之间的通信原理和通信协议,对于速度的设定,采用了定时中断发送数据的方式,实现了线速度的同步;而对于电机的启动和停止,则可采用广播方式或单独发送方式;最后给出了系统的软件流程图。实践表明,该同步控制系统与传统同步控制系统相比具有速度控制灵活、准确和可靠性高等优点。     

基于CAN总线的智能馈线终端的研究

介绍一种基于CAN总线和交流同步采样技术的新型智能馈线终端。重点探讨了该馈线终端的工作原理,系统构成及软件设计思路。     

伪随机码频域相关器同步方案

本文讨论了利用频域相关器输出信号中的频率信息,通过由单片机构成的智能化电路进行快速同步的设计原理。给出了一个具体实例的设计方法和软件框图。     

基于PLC和矢量变频器的涂层机同步传动控制系统的实现

基于PLC和矢量变频器,设计涂层机同步传动控制系统,提出系统的构成和工作原理,给出由PLC、矢量变频器、同步控制器、力矩控制器、交流电动机和张力检测器等装置构成的闭环控制系统,实现涂层机不同传动单元的同步运行.其中的设计方法可用于其它需要同步运行的纺织设备.实际应用表明,这种交流调速系统具有与直流调速系统相同的动、静态控制性能,还具有运行可靠和维护简单的特点.     

基于ISP技术的正交信号激励模块设计

本文利用ISP技术产生了四路同步正交信号，在ISP器件内部实现了脉冲调制，节省了硬件资源，简化了电路设计。本文给出了电路的硬件构成以及逻辑结构和原理。     

矿井提升机行程-速度全数字监控器的研制

介绍了矿井提升机行程 -速度全数字监控器的构成、功能及工作原理 ,指出了以行程为变量的速度给定方式的重要性 ,并讨论了井筒同步校正开关设置的意义及监控器的抗干扰措施。     

基于UC1637的同步发电机励磁控制器设计

详细介绍了UC1637的特点及其工作原理,并给出了其应用于同步发电机励磁控制器的应用电路.实践证明,用该设计方法构成的PWM控制电路结构简单、性能可靠,具有良好的系统运行效果.     

基于远程监控的PLC-多变频器同步调速系统

利用LG=K120S系列PLC与LG-IG5系列变频器共同组成PLC-多变频器同步控制系统,详细说明了利用RS485通信网络、MODBUS通信协议构成同步控制系统的系统组成、工作原理与控制算法等,并利用计算机通过公用电话网对系统进行监控,已在实践中得到应用。     

基于DSP的发电机原动系统仿真器设计与开发

介绍了以DSP单片机为控制核心的同步发电机原动系统仿真器的原理、硬件构成和软件设计，并给出了现场静态和动态测试结果。试验结果表明，该仿真系统能很好地实现对原型电动机各特性的仿真。     

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.