SDRAM在图形生成电路中的应用

针对机载座舱显示器对高分辨率图形实时生成与显示的应用需求,提出了一种基于SDRAM帧存的图形生成电路实现方法。该方法以DSP作为图形处理器执行图形运算算法,以FPGA作为协处理器,对SDRAM帧存采取乒乓操作方式进行图形数据缓冲处理,实现了图形的实时生成。运用该方法只需两片SDRAM器件即可实现分辨率高达1 600×1 200的图形数据的实时生成与显示处理;对时序参数和接口逻辑做少许修改,可生成多种分辨率图形画面。     

基于双处理器系统的图形生成电路研究与应用

机载显示器分辨率越来越高,显示内容越来越复杂,这对图形生成电路提出了更高的要求。提出了一种基于双处理器系统的图形生成电路实现方法,以两片DSP处理器作为绘图核心,配合FPGA和SDRAM帧存构建硬件平台,由主DSP进行绘图任务分配,并将任务分配结果通过Linkport口传递给从DSP,主从DSP根据任务分配结果并行完成图形生成算法运算,从DSP通过Linkport口向主DSP发送图形数据,主DSP将图形数据写入SDRAM帧存中,配合FPGA对SDRAM进行乒乓操作完成图形数据的实时生成与显示。实验结果表明,该方法与单处理器方案相比,在功耗仅增加15%的情况下图形生成效率可提高53%以上,生成一幅1 024×768的EFIS电子飞行显示系统画面帧率可达86 f/s。     

基于FPGA和DSP的高分辨率图像采集系统

介绍了一种高分辨率图像数据采集系统的实现方案.该方案采用了现场可编程门阵列(FPGA)数字信号处理器(DSP)的体系结构,利用FPGA实现图像数据检测、采集、缓冲、预处理,并协调系统各部分的工作,利用DSP对图像数据进行JPEG压缩,通过PC104总线将压缩后的数据上传至主机.该方案中,由FPGA控制的高速大容量同步动态随机存储器(SDRAM)作这图像数据的帧存,解决了高分辨率图像采集中容量和速度上的问题,SDRAM分时供FPGA和DSP访问的机制提高了数据存取的效率.JPEG压缩方法大大降低了数据传输所需的带宽并减少了存储所需的容量.该系统能够对高至2 048×1 536的多种分辨率的图像实现数据采集和压缩.     

基于FPGA的图像融合处理系统方案设计

一种基于FPGA技术的图像处理系统,实现了图像数据的A/D采集、在SRAM以及SDRAM中的存取、在FPGA内部的DSP运算以及图像数据的D/A输出,具备图像融合处理功能。文章在阐述系统结构、总体方案和设计思想基础上,重点论述了系统各模块划分、芯片选型依据以及系统有关模块的接口设计。     

SoC FPGA的视觉算法加速系统设计

提出一种基于Altera SoC FPGA进行硬件加速的方案,该方案为运行在ARM端Linux系统的视觉算法利用FPGA进行加速提供传输通道.首先把ARM端的图像数据传输到FPGA部分的SDRAM中,接着控制FPGA相关IP核读取SDRAM中的数据,然后视觉算法IP核接收图像数据并对其进行加速处理,最后把处理后的图像数据通过特定的IP核传回Linux系统.实验验证了该方案的可行性、可靠性和加速性能.     

用FPGA实现机载全姿态指示仪图形硬件填充

论述一种基于DSP和FPGA的机载图形显示系统，并提出一种新颖的基于FPGA的动态画面的硬件填充方法．在填充操作过程中，由DSP完成画面中填充区域边界的标志运算，FPGA完成填充画面像素的刷新操作，使整个画面刷新的速度大为提高。     

基于Δ-Σ技术和FPGA的数据采集系统

为了改善传统数据采集系统运算能力差、分辨率低、可靠性低等缺点,结合Δ-Σ技术和FPGA,设计了一种多通道、高分辨率、宽动态范围的新型数据采集系统。提出了一种由Δ-ΣA/D转换芯片、高性能FPGA和DSP组成的数据采集系统方案及其硬件电路实现方法。系统利用A/D器件对信号进行滤波、放大、差分转换和模数转换,利用FPGA设计内部模块和时钟信号进行电路控制及实现数据缓存、数据传递等功能,由高速DSP芯片核心控制,对采样数据进行实时处理。系统能实现24位高分辨率、宽动态范围的信号数据采集与高速实时处理,可用于电压、电流、温度等参量的采集系统中。     

基于△-∑技术和FPGA的数据采集系统

为了改善传统数据采集系统运算能力差、分辨率低、可靠性低等缺点,结合△-∑技术和FPGA,设计了一种多通道、高分辨率、宽动态范围的新型数据采集系统.提出了一种由△-∑A/D转换芯片、高性能FPGA和DSP组成的数据采集系统方案及其硬件电路实现方法.系统利用A/D器件对信号进行滤波、放大、差分转换和模数转换,利用FPGA设计内部模块和时钟信号进行电路控制及实现数据缓存、数据传递等功能,由高速DSP芯片核心控制,对采样数据进行实时处理.系统能实现24位高分辨率、宽动态范围的信号数据采集与高速实时处理,可用于电压、电流、温度等参量的采集系统中.     

用Xilinx FPGA实现DDR SDRAM控制器

DDR SDRAM使用双倍数据速率结构,它能获得比SDRAM更高的性能。DDR SDRAM需要特定的DDR控制器才能完成与DSP、FPGA之间的通信。由于Xilinx VirtexTM-4系列FPGA具备ChipSync源同步技术等优势,本设计采用它来实现DDR SDRAM控制器。该DDR SDRAM控制器采用直接时钟数据捕获技术,本文将重点阐述该技术。     

DSP与FPGA协同全景成像中用逆向波形分析实现双核DMA通信

提出基于逆向波形分析的方法,实现DSP与FPGA之间的双核DMA通信,用于满足高分辨率、实时折反射全景成像双核嵌入式系统中DSP与FPGA之间全景图像数据高速传输的需要。其原理是：运用逆向工程思想对传统DMA操作进行波形分析,并根据波形分析结果实现DSP和FPGA的双核DMA数据传输。实验表明,所提出的双核DMA通信方法,DSP与FPGA之间的数据传输速度最高达4.704Gbps（即588MBps）。     

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.     

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.     

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.     

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.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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