基于单片机的边界扫描实验系统的设计与实现

为了将边界扫描技术构架更好地应用于电路可测性设计中,在介绍边界扫描结构、测试基本原理的基础上,提出了运用单片机模拟边界扫描时序,控制被测电路进入相应边界扫描状态的方法;利用模拟开关控制整体扫描链路的转换,同时结合现有CPLD下载电路,完成了被测电路核心逻辑、外围管脚的设置,最后实现了基于IEEE1149.1测试访问门和边界扫描结构标准的边界扫描实验系统;实验系统可以完成IEEE1149.1的所有边界扫描测试,并具有实现简单、操作灵活等特点。     

基于网络的边界扫描测试技术的研究与实现

将边界扫描测试技术应用于远程测试,解决高密度电路系统及复杂测试环境带来的测试问题,可实现仪器设备的远程测试与故障诊断:深入研究了IEEE1149.1边界扫描测试标准,提出了一种基于SPI接口的边界扫描测试控制器设计方案,设计网络接口电路及硬件底层驱动程序,并组建基于网络的边界扫描测试系统硬件平台;对被测电路进行测试验证,测试结果表明,该测试控制器可产生符合IEEE1149.1标准的JTAG测试信号,该测试系统可完成边界扫描的远程测试,硬件结构简洁且使用灵活,有较高的性价比,具有较好的应用前景.     

基于边界扫描的模拟电路BIT技术研究

边界扫描技术在模拟电路的可测性设计大多仍停留在IEEE1149.4标准所规定的模拟测试总线上,并没有做到真正意义上的内建自测试设计;针对模拟电路信号提取和比较相对困难的测试难点,提出采用方波脉冲作为测试激励信号的方法,并以模拟开关为辅助桥梁,设计了基于边界扫描的模拟电路BIT结构;通过各个模块功能的时序仿真证明了该结构设计的合理性,并以集成运放uA741作为被测电路,通过信号上升沿脉冲计数充分证明该结构的可行性。     

STA400TEP芯片在模拟电路BIT设计中的应用研究

在大规模集成电路中,模拟信号的测试是一个重点和难点;介绍了IEEE1149.4混合信号测试总线标准和支持IEEE1149.4标准的STA400TEP边界扫描芯片,对STA400芯片在模拟电路机内测试中的应用进行了研究,提出了一种基于子网络撕裂诊断法的边界扫描结构置入的测试性设计方法,并以某驱动电路为研究对象对此方法进行了实验验证,实验结果表明STA400TEP的置入能够实现电路板的可观性和可控性,能够准确地将故障定位到子网络中。     

基于网络的混合信号边界扫描测试系统的设计与实现

将边界扫描技术与网络技术结合,解决高密度电路系统特别是混合信号电路及复杂测试环境带来的测试问题,可实现远程测试与故障诊断;设计了一种基于网络的混合信号边界扫描测试软硬件系统,硬件部分设计了边界扫描测试控制器、网络接口电路并实现了硬件底层驱动程序,软件部分实现了边界扫描测试系统程序和网络接口功能函数;对被测电路进行测试验证,测试结果表明系统可完成混合电路的远程边界扫描测试,具有较好的应用前景。     

基于在线测试的边界扫描器件测试原理

当今,微电子技术已进入集成电路(VLSI)时代.随着芯片电路的小型化及表面封装技术(SMT)和电路板组装技术的发展,使得传统测试技术面临着巨大的挑战.为了提高电路和系统的可测试性,提出了一种新的电路板测试方法-边界扫描测,也称JTAG标准.本文简单介绍基于BoundaryScan器件在ICT设备中测试原理.     

建立在模拟集成电路上的边界扫描设计

对模拟芯片边界扫描测试方法进行了研究,结合IEEE1149.1标准框架结构和IEEE1149.4标准混合信号测试总线思想构建了模拟芯片边界扫描测试电路,运用了数字移位寄存器和模拟开关构成模拟边界扫描单元,并编写了TAP控制器及其它电路的VHDL代码,通过实验仿真验证了测试电路的可行性。测试电路可以完成模拟芯片的简单互连测试以及性能测试。     

基于SOPC的边界扫描测试控制器IP核设计

在研究边界扫描数字电路测试技术标准IEEE1149.1的基础上,采用SOPC设计技术,用FPGA设计实现了一款基于Avalon总线的边界扫描测试总线控制IP核,与其它复用IP核可形成以NIOS Ⅱ处理器为核心的通用数字电路边界扫描测试控制器,该控制器产生符合IEEE1149.1标准的测试信号控制被测边界扫描系统,进行各种边界扫描测试;该IP核的成功设计,为基于边界扫描的电子系统机内自测试系统的实现,奠定了坚实的应用基础。     

基于IEEE 1149.4标准的模拟电路功能性测试模型研究

IEEE 1149.4混合信号电路边界扫描测试总线标准为模拟电路的可测性设计提供了一个基本的框架,但具体的实现方法需要研究人员进行设计。用开关矩阵、单片机、dds芯片构成了基于IEEE 1149.4标准的模拟电路功能性测试模式。经可控性、可观性试验,能够反映IEEE 1149.4标准中针对模拟电路的边界扫描构架与思想,为更多将边界扫描应用于模拟电路的可测性设计中去,打下了良好的基础。     

从1149.1标准到1149.7标准分析边界扫描技术的发展

边界扫描技术是一种应用于集成电路的测试性结构设计方法,其主要优点在于用极少的电路引脚解决了极为复杂的电路测试问题;伴随着边界扫描技术的发展,已经具有IEEE1149.1、IEEEIEEE1149.4、IEEE1149.5、IEEE1149.6等多个标准,它们所提供的解决方案极大地方便了芯片级、板级、系统级及数字网络的测试;文中对边界扫描的多个协议标准进行了介绍和分析,着重讨论了各个标准的体系结构及功能,最后介绍了边界扫描技术面临的挑战及今后的发展方向。     

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.