基于NiosⅡ的PCI Express接口卡的设计

根据NiosⅡ软核处理器的组成原理,提出了一种基于NiosⅡ的PCI-Express(简称PCIE)接口卡的设计方法,研究了系统对LVDS信号的处理和应用PCIE总线接口通信的过程;详细讨论了系统各功能模块的实现原理,并对各模块进行了实际的分析和测试,测试结果表明该接口卡性能稳定,可以有效地完成数据传输。     

VXI总线四通道LVDS数据传输模块设计

针对国内测试系统开发中出现的低电压差分信号(LVDS)技术需求提出了一种VXI总线四通道LVDS数据传输模块的设计实现方法;以FPGA作为控制核心,利用Verilog HDL设计实现了VXI接口和HDLC通讯协议设计,并通过基于VXI总线的块传输方式和乒乓存储技术,完成了大批量数据的接收;另外,为确保LVDS信号的完整性,结合实际设计和调试经验,文中还分析了LVDS接口信号印制板布线和布局问题;该模块已用于测试系统开发,并实现了测试系统与被测设备的视频信号传输;应用结果表明,模块传输速度为4Mbit/s时误码率小于10-6。     

基于PCIE的高速光纤图像实时采集系统设计

利用PCI Express(PCIE)总线及DMA数据传输技术,设计光纤图像实时采集系统.利用FPGA中的PCIE硬核实现了PCIE总线的DMA传输,同时介绍了整个采集系统的数据流和光纤接口模块的设计.测试结果表明,系统DMA数据传输速度可达到138 MB/s,完全满足高速光纤图像实时采集的需要.     

遥测数字视频信号高速采集存储系统的设计与应用

介绍了遥测数字视频信号的高速采集与实时存储,主要阐述了系统整体设计、存储器硬件设计、FPGA逻辑时序设计以及系统自检测试;其中硬件设计包括数据解码、Flash硬件设计以及LVDS调度模块,时序设计包括视频信号采集模块时序和Flash读写擦控制时序;本设计由FPGA来控制视频信号的高速采集和图像数据的高速串化与解串,通过LVDS接口传输方式进行Flash存储,再将存储模块中的数据读出,发送至地面综合测试台进行解包分析,完成自检功能。其中输入数据码流为31MB/s,供电电压28V左右,帧率为100帧/秒;本设计具有高码流、存储容量高的特点,大大提高了遥测系统的可靠度,已经在项目中得到应用。     

基于LVDS和PCI接口的高速图像传输系统设计

针对数字图像处理与传输领域数据量大而传统接口无法满足其高速率传输要求的现状,提出了一种基于LVDS和PCI接口的高速图像传输系统的设计,对系统总体设计和各电路模块进行了详细介绍和分析,并对系统整体功能进行了测试。该系统以FPGA作为控制核心,采用乒乓操作实现数据的无缝缓冲,重点研究了LVDS接口和PCI总线技术,保证图像数据的高速、可靠传输。测试结果表明,该传输系统性能稳定,能可靠地实现图像数据传输,最大传输速率可达18 MB/s,具有一定的实用价值。     

基于DSP和FPGA的全景图像处理系统设计与实现

设计了基于DSP和FPGA的全景图像处理方案,FPGA完成图像采集,DSP完成图像的各种处理算法。利用FPGA设计了基于乒乓缓存机制的SDRAM控制器;采用EDMA方式,完成了DSP与FPGA的数据交换。测试结果表明,DSP+FPGA折反射全景图像处理系统完成了对分辨率为2 048×2 048、每秒15帧的Camera Link接口的全景图像的实时采集及缓存解算,并以1 024×768的分辨率进行实时显示。     

1394总线在实时图像系统中的应用

随着红外成像技术的不断发展,红外图像的数据量越来越大,成像的速度也越来越快,这就要求红外成像系统具有实时采集、实时处理、实时传送大批量数据的能力;但是现有的大部分数据传输接口速率较低,难以满足现实中对速度越来越高的要求;将1394高速申行接口引人到红外成像系统中,完成了1394接口电路硬件及软件的设计,并在微控制器(MCU)和FPGA的控制下实现了红外图像的高速传输、实时显示,大大提高图像数据的采集速度和系统的整体性能;测试结果表明,通过1394总线每秒可以传输42帧大小为320 * 240的红外图像,并实现了图像的实时清晰显示,满足了红外成像系统实时采集实时显示红外图像的要求.     

基于LVDS的高速图像数据存储系统设计

介绍了一种基于LVDS的高速远程图像数据存储系统.系统以FPGA芯片作为控制核心,采用低压差分信号技术(Low voltage differential signaling,LVDS)接口解串和驱动芯片相结合,保证了有效接收远程数据;采用交替双平面的FLASH编程方式来控制图像数据的存储,实现了以28.95 MB/s的速度对实时图像数据进行存储的要求.经试验验证和实测证明,该图像数据存储系统性能稳定,数据存储可靠,能满足实际测试要求.     

基于eMMC阵列的高速大容量数据的存储设计

为实现对某飞行设备进行模拟飞行测试,需要对大量的飞行仿真数据进行快速存储,因此提出一种基于eMMC (em-beded MultiMedia Card)阵列的高速大容量数据的存储设计;设计选用FPGA (field programmable gate array)作为逻辑控制核心,通过控制其内部IP核GTX (Gigabit Transceiver)实现与外部设备的通讯,为匹配数据的传输速率,采用缓存模块对GTX模块输出的并行数据进行缓存,依据缓存大小来控制eMMC阵列控制器模块对eMMC阵列进行写入;系统上电后,GTX模块及eMMC阵列控制器模块自动进入初始化流程,上位机通过RS422接口发送启动命令给FPGA,当FPGA检测到各模块初始化完成标志后,通过RS422接口上传指令回应帧并启动数据的采集存储;数据存储完成后,为验证数据传输存储的正确性,上位机发送读取命令对数据进行回读;经验证,回读数据正确,无丢帧错帧的现象,数据传输稳定可靠,数据存储速率为2.4 Gbps;系统设计正确,为模拟飞行测试提供了可靠的保障.     

基于FPGA的地检系统设计与实现

系统是为某型号新一代航天载荷可见光通道设计;主要功能是实现可见光通道的图像的实时采集与获取,完成可见光通道的地面调试与性能检测;文中针对测试需求提出了完整设计方案和软硬件实现方法;系统采用Xilinx新一代低功耗现场可编程门阵列(FPGA)作为控制核心,通过自顶向下的程序设计方法完成硬件时序驱动和逻辑控制;系统主要完成了机械接口设计,CMOS探测器的电路设计与时序驱动,光电压信号的放大、滤波与数模转换,图像数据与上位机的传输接口设计以及上位机软件设计;高速数据传输通过USB接口来实现;经测试验证,系统功能良好,能很好地满足实际工程需求。     

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.