印刷电路板接点可靠度量测系统

本文通过对印刷电路板(PCB)异常电阻的监测，建立了PCB板的可靠度量测系统。首先对各种PCB测试样板进行回路设计，然后利用异常电阻监测仪获取相应电路板的电阻值，构成PCB板的可靠度标准数据库，最后将实际电路板的测试数据与标准数据相比较，得出失效接点的分布情况。     

基于虚拟仪器的功放参数测试仪设计

在生产过程中,当功放电路板(PCB)组装完成后,需要对电路板的功能进行测试,以模拟电路板的工作状态,即在PCB板的输入端加激励信号,输出端加负载,测试电路板的输入输出电气参数是否在设计范围之内。文中基于LabVIEW的虚拟仪器技术平台,并结合高性能的多功能数据采集卡,设计了一种功放测试系统,该系统可以测试最大不失真输出电压、总谐波失真度(THD)、下限截止频率(fL)等参数。通过对一个音频功放进行实验测试表明,系统测试效果良好。     

Protel PCB 99SE手工快速绘制电路板技术

众所周知，Protel 99SE是一款功能非常强大的电路设计与制板软件，除了能绘制出非常理想的标准电路图外，它还有将绘制的电路图转换成印刷电路板的功能，这就是Protel PCB技术。同样，Protel PCB技术先进、功能强大、设计严密。它除了能进行手工、半自动布线绘制电路板之外，也能自动布线绘制电路板；它除了能绘制简单的电路板之外，也能绘制非常复杂的电路板：     

基于ARM的便携式故障检测系统

传统的装备测试诊断技术保障模式,已经难以适应现代电子装备技术保障需求,文章给出了一种以ARM和μC／OS-Ⅱ为开发平台、以MiniG UI为图形开发工具的构建PCB磁场映像的便携式故障自动检测系统,以满足电子设备故障的快速诊断定位和现场维修保障。     

无线传感器网络近场信号测量可调探头设计

在无线通信技术中,很多组网技术使用了近距离局域无线网和远程通用分组无线业务(GPRS)等多个频段,在通信模块的调试和检测中,对相应频段的近场探测是很有必要的。提出一种基于光电式电源的可调频多频段探头。通过CST仿真软件,对基于印刷电路板(PCB)基板的带状线进行建模优化。对应目标中心频率得到一个天线结构和尺寸,再经过外部调整电路将探头的谐振频率点调整到期望的数值,以满足对多频段近场测量的要求。为了降低外部供电电源对探头的影响,选用能够调节功率的光电型电源作为探测装置的能量供应。经实际测试验证,最终制作的近场探头可获得4个固定的谐振频率点,分别位于327. 046,693. 649 MHz,1. 699 GHz和2. 439 GHz,可广泛用于常用无线通信的近场测量调试。     

基于仿真的数字电路板自动测试系统

文章详细描述了LASAR数字仿真软件的测试数据生成流程和基于数字仿真的电路板自动测试系统，利用该系统可以避免数字电路板测试维修过程中，电路板测试程序集人工开发和手工诊断带来的错误，最终有效地提高电路板诊断数据生成和测试诊断效率。     

边界扫描技术及其在PCB可测性设计中的应用

阐述了边界扫描技术的基本原理,从设计方法、优化策略及实现技术等方面,对基于边界扫描技术的PCB可测性设计进行了研究,并给出了具体的实现方法;以对某海军导弹通用测试系统中的数据采集电路板进行改进为例,实现了该电路板的可测性设计;经验证,该方法有效地缩短了数据采集电路板的开发周期,降低了其维修测试费用,因而将具有更为广泛的应用前景.     

基于网络点集合分割算法的PCB故障测试研究

文章研究了印制电路板(PCB)网络点集合分割算法,提出了网络集加激励产生响应的测试算法,给出了基于该算法的测试逻辑电路和控制流程图。实践表明,该算法较好地解决了网络点数与测试速度的矛盾,是快速检测PCB短路故障的一种有效方法。     

基于虚拟仪器技术的边界扫描测试仪的设计

设计了一种基于虚拟仪器技术的边界扫描测试仪,该测试仪采用PC机控制整个测试、诊断过程;首先通过下载电缆将测试指令从打印机端口送往被测PCB,采用边界扫描技术完成测试工作,然后将测试响应上传至PC机,由智能故障诊断软件对响应做相应的分析和运算,获得对PCB的诊断结果。     

PCB你到底是什么？

我们在杂志上为各位介绍的主机板，或是显示卡等等的计算机零件，它们最重要的部份，莫过于印刷电路板（Printedcircuitboard，PCB）了。您可以由它身上测得各项实际的规格以及测试数据，不过另一方面，您也可以仔细研究它，看看许多设计者将他们的艺术才能，都发挥在这精密的制造过程上。PCB本身可说是电子设计之美，以及纯熟技术的结合。接下来我们将带领各位看看PCB的世界，虽然我们不敢说探讨到多艰深的技术，不过我们尽可能的让这篇文章涵盖的范围更广，为各位读者们提供一个全面的概念。什么是PCB？印刷电路板（Printedcircuitb…     

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.