基于SPC3的PROFIBUS-DP的研究与开发

现场总线综合了数字通信、计算机、自动控制、网络和仪表等多种技术手段已成为自动控制发展的趋势.针对现场总线在我国的应用和发展现状,研究了 PROFIBUS-DP 现场总线基本理论,提出了 PROFIBUS-DP 智能从站接口的软硬件设计和实现方法,利用 PROFIBUS-DP 协议芯片SPC3和ARM处理器开发出具有 PROFIBUS-DP 接口的数字量输入输出智能化从站接口模块,最后,实现了一个PROFIBUS-DP 现场总线系统.     

基于PROFIBUS-DP总线的数据通信

通信问题是现场总线控制系统集成的一个重要问题,本文探讨了现场总线PROFIBUS-DP的通信原理以及在柔性制造系统中基于现场总线PROFIBUS-DP的数据通信的实现.     

PROFIBUS现场总线在烧结机控制中的应用

介绍了PROFIBUS-DP现场总线技术的主要特点,论述了基于PROFIBUS-DP现场总线的烧结机控制系统的软、硬件配置以及系统的优越性.     

基于PROFIBUS-DP现场总线的煤矿井下胶带监控系统

介绍了PROFIBUS-DP现场总线技术的主要特点,论述了基于PROFIBUS-DP现场总线的煤矿胶带监控系统的软、硬件配置以及两者之间接口的实现方法。     

基于PROFIBUS-DP的拉丝机控制系统设计

本文设计了一种采用PROFIBUS-DP现场总线构成主从结构的直进式拉丝机交流变频同步调速控制系统,论述了其硬件结构和控制过程,详细介绍了PROFIBUS-DP总线通信接口的实现方法.     

PROFIBUS-DP现场总线在SBR法污水处理控制系统中的应用

主要介绍了一种基于PROFIBUS-DP现场总线的污水处理控制系统.该系统由上位机、PLC和相关设备组成,通过现场总线PROFIBUS-DP和上位机能比较全面的了解现场,能对整个污水处理过程实现自动控制和手动控制.并且就工艺的灵活多变提出了一种新的软件设计思想--工艺字、状态字配合组态软件,适当变化控制工艺的要求的软件设计思想.     

PROFIBUS-DP现场总线性能分析

本文对PROFIBUS-DP现场总线的网络访问机制进行了详细的探讨,建立了PROFIBUS-DP主站间令牌访问和主从站间主从访问机制的模型,通过分析协议的编码效率、通信过程和通信时间参数,定性定量讨论了PROFIBUS-DP现场总线的实时性、确定性和网络利用效率,并得出有理论和实用价值的结论。     

PROFIBUS通信性能测试与参数设置分析

PROFIBUS现场总线协议的实时性是评价其性能的关键因素,因此,如何研究和计算实时性能参数显得尤为重要. 针对这一问题,在对PROFIBUS总线存取协议深入分析的基础上,设计了基于PROFIBUS-DP通信性能测试平台. 通过测试平台分析和计算了包信息率、传输效率、网络平均利用率、网络吞吐量、传输延迟和令牌循环时间等实时性能参数,并给出了总线循环时间与主站个数及报文数量之间的关系之间的关系,从而定性定量分析了PROFIBUS-DP现场总线的实时性能.     

PROFIBUS-DP智能从站通信接口的研究和设计

PROFIBUS-DP是一种开放的国际现场总线标准,用于分散外设间的高速数据传输,SPC3是开发DP智能从站通信接口的专用协议芯片.首先概述PROFIBUS-DP总线协议,分析了SPC3的结构和功能,然后应用SPC3实现DP智能从站通信接口的软硬件设计.     

S7-300PLC控制系统以及现场总线在PECVD中的研究

简述了S7-300PLC控制系统以及PROFIBUS-DP现场总线在制减反射膜及钝化设备中的研究.     

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.