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。     

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.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

法律信息库系统

本文分析了法律数据库的结构和特点，介绍了采用面向对象设计方法和超文本数据库技术开发和实现法律信息库系统将作为重要网络资源之一为不同用户进行法律咨询服务。     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

International Journal of Automation and Computing Table of Contents

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Information for authors

正SCIENCE CHINA Information Sciences(Sci China Inf Sci),cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press,is committed to publishing highquality,original results of both basic and applied research in all areas of information sciences,including computer science and technology;systems science,control science and engineering(published in Issues with odd numbers);information and communication engineering;electronic science and technology(published in Issues with even numbers).Sci China Inf Sci is published monthly in both print and electronic forms.It is indexed by Academic OneFile,Astrophysics Data System(ADS),CSA,Cabells,Current Contents/Engineering,Computing and Technology,DBLP,Digital Mathematics Registry,Earthquake Engineering Abstracts,Engineering Index,Engineered Materials Abstracts,Gale,Google,INSPEC,Journal Citation Reports/Science Edition,Mathematical Reviews,OCLC,ProQuest,SCOPUS,Science Citation Index Expanded,Summon by Serial Solutions,VINITI,Zentralblatt MATH.     

Erratum to: Fast global kernel fuzzy c-means clustering algorithm for consonant/vowel segmentation of speech signal

正Erratum to:J Zhejiang Univ-Sci C(ComputElectron)2014 15(7):551-563doi:10.1631/jzus.C1300320The original version of this article unfortunately contained mistakes.Algorithm 6 should be as follows:Algorithm 6 FGKFCM-F clustering Input:(1)X={x_1,x_2,…,x_N},,x_iR~d,i=1,2,…,N,the dataset;(2)C,1C≤N,the number of clusters;(3)ε0,the stopping criterion;     

Journal of Zhejiang University-SCIENCE C (Computers & Electronics) Total contents

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A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.