基于FPGA和AD768的高精度信号卡设计

遥测匹配装置的自检与测试是系统设计中不可缺少的一项功能,而信号卡是匹配装置自动测试系统的重要组成部分.本文介绍了一种高精度信号卡的设计,它采用Xilinx公司的可编程逻辑器件XCF2S50E及AD768来实现.采用FPGA简化了电路设计,提高了系统的设计灵活性;采用16位的D/A变换器AD768则提高了信号卡的精度.     

基于FPGA的高阶FIR滤波器强抗干扰数据采集系统

介绍了一种适用于在强干扰、关键信号被无用信号淹没的情况下,实现高精度数据采集的系统。系统硬件上采用24位高精度A/D采集模拟信号,采用XILINX公司的FPGA作为主控制器;软件上通过从A/D读取数字化后的信号,再进行高阶FIR滤波,剔除了干扰信号。通过FIR滤波在数据采集系统中的运用,采集系统可以较传统数据系统有更高的采集精度和更强的抗干扰能力。     

FPGA中低噪声CCD时序驱动电路设计

在分析Toshiba公司TCD1209D型CCD工作原理的基础上,分析了驱动时序的关系,详细介绍了驱动电路的设计和实现方法.用Verilog语言设计了TCD 1209D的驱动时序控制电路;选用CyclonelⅣ系列FPGA器件,使用QuartusⅡ软件对设计电路进行了功能仿真,实现了TCD1209D的高速时序驱动;在CycloneⅣ芯片平台上测试了TCD 1209D的实际输出信号.实验结果显示,CCD信号噪声较小,验证了所设计驱动电路的可行性,确定了相关双采样的时刻和位置,为小型CCD测量系统的设计提供了有益参考.     

基于DSP信号采集系统设计与实现

介绍了一种基于TMS320F2812 DSP芯片设计的信号采集系统,讨论了系统硬件组成中信号调理模块和A/D转换模块的设计要点,同时介绍了FIR数字滤波器在DSP中的实现方法.     

一种基于DAB接收机的MP3播放器设计方案

提出了一种基于便携式DAB(Digital Audio BroadcaSting,数字音频广播)接收机的MP3播放器设计方案,并介绍了系统的软硬件设计思路.系统采用ARM7单片机作为系统控制器,利用SD卡存储MP3文件,用ST公司的音频解码芯片STA013实现MP3解码.数字语音信号通过D/A转换器MAX9850转换为...     

基于DSP的高速音频采集系统的硬件设计与实现

本文介绍了一种基于TI公司的DSP芯片TMs320VC5402的高速音频采集系统,该系统能对音频信号进行在线实时采集、存储及回放,并能通过USB外围接口器件实现与上位机的通讯。主要介绍了音频采集系统的总体方案和硬件实现,包括DSP模块、A／D和D／A模块、扩展存储器模块、CPLD控制模块、电源模块以及USB接口通讯模块等。该系统具有强大的数据采集处理能力并配有灵活的接口电路,可以作为研究音频信号采集与处理的通用平台。     

DSP嵌入式系统图形用户显示GUI的设计与实现

近几年来,由于DSP芯片具有高性能数字信号处理能力,它已经越来越多地被广泛用于高速实时信号处理、语音处理、图形分析处理等.基于DSP平台嵌入式系统是一种高集成度、高专用性的系统,在便携式多媒体信号处理和实时设备中获得了大量应用.本文提出了以EPSON公司生产的S1D13503芯片作为DSP嵌入式系统的显示控制芯片,实现DSP嵌入式系统图形用户显示.本文还着重介绍了S1D13503控制器的原理和讨论了以该控制器为核心并基于DSP控制的液晶显示的一种硬件、软件设计解决方案.     

一种基于A/D和DSP的高速数据采集技术

雷达接收机将雷达回波信号变成中频信号,数字信号处理系统对中频信号采样和处理.本文介绍一种基于A/D和DSP的中频信号采集技术;给出数据采集系统的原理和框图,并对A/D与DSP的接口电路进行分析.用FIFO作为两者之间的接口效果很好;DSP通过CPLD对采样时序进行控制,可增强系统的灵活性.     

一种用单片机控制的光谱数据采集系统

介绍利用单片机和A/D器件MAX120等构成的光谱信号采集系统,由单片机控制A/D产生不同的采样频率,用于光电倍增管和CCD输出的光谱信号的采集.     

基于DSP6000数字IMU信号处理板设计

介绍了一种基于DSP6000数字IMU信号处理板设计方案,应用TI公司的TMS320C6713DSP器件为中心处理器,采用LINEAR公司的LTC1606完成模拟信号的A/D转换.详细介绍了该信号处理板硬件电路设计中各个模块的功能、组成和设计方法,并对信号处理板软件流程做了详细说明.实验结果表明,该信号处理板提高了数据处理速度、减小了系统体积和成本,同时具有实时运算能力强等优点,可支持多种补偿算法.     

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。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。