一种并行高速读取的存储器模型

为解决高速CPU与低速主存储器两者速度的平衡和匹配问题,提出一种并行高速读取的存储器模型,对其结构组成、基本原理、数据读取算法以及时间估算作了分析,最后通过仿真实验验证了其正确性和可行性.该模型具备一般的猝发式存储器和双端口存储器的数据读取特点,可以高速读取成组连续数据,大幅度地提高了微处理器系统的整体性能.     

TMS320VC5509的二次引导加载方法

在嵌入式系统中，微处理器的运行程序通常保存在其内部或外部非易失性存储器（如EPROM、EEPROM或Flash）中。对中低速的微处理器来说，系统运行时程序可直接从非易失性存储器读取并解释执行；对高速微处理器来说，非易失性存储器的读取速度较低，不能满足系统运行时程序代码直接读取的要求，需采用引导加载（Boot—load）方式将程序代码从低速非易失性存储器中加载到高速的存储器（如SRAM或DRAM）中，系统运行时直接从高速存储器中读取程序代码，实现系统的高速运行。因此引导加载是高速微处理器系统的关键技术之一。     

基于FPGA的TigerSHARC DSP程序快速加载方法

Tiger SHARC DSP加载程序的传统方式是DSP上电后通过外部总线读取外部存储器中的程序数据,该方式加载程序速度慢,不能满足高速系统的使用要求。介绍了一种快速的DSP程序加载方法,采用FPGA读取外部存储器中的程序数据,并通过Tiger SHARC DSP的高速Link口对DSP加载程序。与传统方式相比,该方法可有效提高程序加载速度,缩短系统启动时间。     

单片机系统在系统编程技术的实现

讨论了运用ISP技术并结合Flash存储器AT29C020的特点实现基于P87C591的单片机系统的可在系统编程功能的方法及相关技术,介绍了向单片机传送目标文件的上位机(PC)需完成的串行通信、读取目标文件、传输校验等任务的实现方法.     

单片机控制的OLED全彩色静态和动态视频图像显示

构建了以单片机为控制器的OLED显示系统,分析了显示驱动芯片的工作原理.在PC机上生成图像数据流,该数据流经RS-232串口或USB接口传输到与单片机外接的数据存储器,单片机控制读取存储器中的数据,在OLED显示屏上实现各种全彩色字符、静态图像和视频动态图像显示.     

基于STM32的Flash存储器坏块自动检测

针对Nand Flash存储器存在坏块的问题, 提出一种基于STM32的Flash存储器坏块自动检测方法, 通过STM32内部可变静态存储控制器, 发出相应的数据、地址、控制信号, 在不增加外部器件的情况下, 快速访问Flash存储器, 并给出了部分硬件电路和C语言编写的程序代码. 该设计已成功实现自动检测Flash坏块的功能; 操作简单、检测速度快、准确率高; 并能读取Flash的ID号检测Flash性能, 同时能够存储和读取2GB数据.     

千兆以太网高速数据通信记录系统

为开展航空、航天领域各项专项试验并实现数据获取与分析,提出了一种基于FPGA的具备千兆以太网接口的高速数据通信记录系统的设计方案,详细描述了该记录系统的功能设计、硬件设计、接口设计、嵌入式软件设计方法,其主要功能是通过通信接口与配套使用的系统进行通信,在通信过程中,将所有的通信数据记录至非易失性存储器中,事后通过数据读取接口将记录的数据读取至上位机完成数据处理与分析.     

基于ARM与FPGA图像采集存储系统设计

设计实现了一种基于ARM与FPGA高速图像采集存储系统.该系统采用视频编码芯片SAA7113和FPGA实现高速视频采集,采集数据经由ARM处理器读取并存储到大容量硬盘存储器,为数字图像的后续处理提供了可能.     

低端嵌入式系统的图像采集

介绍MT9V011 CMOS数字图像传感器在一个基于低端ARM7处理器和CPLD（可编程逻辑器件）的嵌入式系统中的应用.通过一片CPLD读取MT9V011采集的图像并缓存到存储器以备后续的处理.利用PC平台验证了图像采集功能.给出了一个在低端嵌入式系统中增加图像采集功能的实现方案.     

基于ARM的同步发电机故障录波系统的设计

介绍了一种发电机故障状态数据录波系统设计方法。利用了高速ARM芯片及高精度三相计量芯片ADE7758组成交流采样电路,从而能实现高速数据采集和转换,将故障前后的数据保存在铁电存储器中。在VB环境下实现计算机与ARM的串行通信,读取铁电存储器FM24C256中保存的故障数据并用图形显示出来。实践证明该系统图形界面友好、可靠性高、操作方便、应用效果好。     

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.     

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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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