基于AT89S52的CAN通信接口设计

随着人们对总线各方面要求的不断提高，总线上的系统数量越来越多，随之产生诸如电路复杂性增加、可靠性下降、生产成本增加等问题。为解决上述问题文中提出了一种低成本的CAN总线通信接口的设计方案。在器件选型上采用了ATMEL的典型芯片AT89S52作为主控单片机，分别从硬件电路设计和软件初始化、发送、接收设计分析，给出了部分C语言设计代码，以CAN2．0B协议来执行，既实现了应有的网络控制功能，又降低了系统的开发、生产和服务成本，具有较高的实用性。     

地面CAN总线隔离器测试台的设计

该文设计了一种CAN总线隔离器测试台对CAN总线隔离器的性能进行全面测试。由于CAN总线隔离器是对飞行器系统内弹上高速遥测设备和地面低速测试设备之间进行速度隔离,它可以确保飞行器弹上遥测设备和地面测试设备之间稳定实时通信,所以测试台对隔离器进行性能测试时模拟了地面测试设备和弹上遥测设备同隔离器之间的通讯。该文中设计了统一的通信协议分别模拟弹上CAN节点和地面CAN节点同隔离器之间的通讯。在实际应用中,该CAN总线隔离器测试台设计可行,能全面检验CAN总线隔离器的性能。     

基于CAN总线的温度测量节点设计

介绍了CAN现场总线技术及特点,提出了一种基于CAN现场总线的单个温度测量节点的设计,给出了测量节点的硬件实现框图、软件设计。系统运行结果证明：CAN总线提高了信号传输的实时性、可靠性,增加了传输距离,测量精度也得到了显著的提高。     

CAN总线技术在PROTOS70卷接机组上的应用

介绍了卷烟厂信息化建设中底层设备采用CAN总线进行分布式控制和数据集中处理的必要性,在PROTOS70卷接机组上CAN总线的连接方式,每个设备需要接收的数据和发送的数据,通过CAN总线通信完成数据发送与接收,实现集中处理与分散控制。介绍了MLP监控系统和CIS质量检测系统、SRM重量控制系统、紧头跟踪控制系统、故障显示器的CAN总线节点设计方法。采用CAN总线技术实现了卷烟机上设备分布式控制,实际运行效果稳定可靠。     

基于CAN核的四冗余通信板设计与仿真

针对市场上的总线通信板实际传输速率低和综合性能不高的问题,提出了一种利用FPGA设计CAN核,并在此基础上进行CAN通信板的设计。该通信板完成PC／104与CAN总线通信,具有“双光双电”的四冗余设计。详细介绍了CAN核的设计、CAN通信板的硬件设计及软件设计,并利用Modelsim对设计进行系统仿真。该CAN通信板具有高速、高可靠的特点,其通信速度、误码率、可靠性等指标均达到了设计要求。     

基于FPGA和CAN控制器软核的CAN总线发送系统的设计与实现

基于FPGA嵌入式片上系统可编程技术,采用现有的CAN总线控制器软核模块,设计了软核控制程序,将由CAN控制器软核及其控制程序组成的CAN发送软件嵌入在FPGA内部,开发了CAN总线通信系统,实现了对CAN总线数字量的发送;经过软件仿真验证、静态时序分析和硬件系统测试,仿真和测试结果表明,该系统设计合理,方案可行,时序正确,功能、性能满足要求;系统将硬件软件化,有效的减少了外围芯片的数量,降低了系统的体积和功耗,提高了产品的集成度、通用性和可靠性,具有良好的实用价值和推广前景。     

基于CAN／LIN总线的汽车通信网络设计

随着人们对汽车各方面要求的不断提高，汽车上的电控系统数量越来越多，随之产生诸如电路复杂性增加、可靠性下降、生产成本增加等问题。为解决上述问题文中提出了一种基于CAN总线和LIN总线技术的现代汽车通信网络的低成本设计方案。设计中将CAN总线技术用于高速的驱动系统中，将LIN总线技术（其节点成本是CAN的1／3～1／2）用于低速的车身系统中，在器件选型上采用了PHILIPS和FREESCALE的典型汽车电子芯片，既实现了应有的网络控制功能，同时也降低了车辆电子系统的开发、生产和服务成本，具有较高的实用性。     

基于冗余CAN总线的实时通信系统设计

针对航天现场工业环境对通信系统的可靠性有较高的要求,该文提出了基于冗余CAN总线的实时通信系统设计方法,该方法为系统的CAN网络主节点进行节点冗余设计,同时对CAN网络中的每个节点进行总线冗余设计.当主节点出现故障时系统切换到备份主节点工作,当总线出现故障时系统切换到备份总线上工作.该系统制定了统一的通信协议,系统主控模块FPGA对整个CAN网络中的节点进行实时监控,有效提高了系统数据传输的可靠性.     

基于CAN总线的A320飞行模拟机接口系统设计

为解决目前A320进口飞行模拟机接口系统速度慢、故障率高的问题,设计基于CAN总线的飞行模拟机接口系统有着重要的意义。阐述了空客A320飞行模拟机CAN总线接口系统的系统功能和设计方法,并对其硬件设计、软件设计和通信机制的设置进行了详细论述,最后对CAN总线接口系统进行了测试。测试结果表明,该CAN总线接口系统能够满足空客A320飞行模拟机的设计要求,运行速度更快,工作更稳定,获得了满意的结果。     

基于CAN/LIN总线的汽车通信网络设计

随着人们对汽车各方面要求的不断提高,汽车上的电控系统数量越来越多,随之产生诸如电路复杂性增加、可靠性下降、生产成本增加等问题.为解决上述问题文中提出了一种基于CAN总线和LIN总线技术的现代汽车通信网络的低成本设计方案.设计中将CAN总线技术用于高速的驱动系统中,将LIN总线技术(其节点成本是CAN的1/3～1/2)用于低速的车身系统中,在器件选型上采用了PHILIPS和FREESCALE的典型汽车电子芯片,既实现了应有的网络控制功能,同时也降低了车辆电子系统的开发、生产和服务成本,具有较高的实用性.     

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.