基于实时操作系统T-Kernel的多任务软件设计

研究基于实时操作系统T-Kernel的多任务软件设计。首先介绍了实时操作系统T-Kernel的基础知识,包括任务管理、同步与通信管理和中断管理等。以一种基于T-Kernel的播放器软件设计为例,描述了进行多任务设计,主要是软件的多任务划分和设计编程,最后介绍开发播放器软件的经验并进行了总结。     

基于T-Kernel的CF卡驱动程序设计

介绍了T-Kernel的两种设备驱动程序接口及相关函数,解析和设计T-Kernel的CF卡驱动开发流程.     

T-Kernel任务调度的实时性分析

T-Kernel由于其实时性及开源性，在全球微处理器操作系统市场中已占据了一半以上的份额。该文分析了T-Kernel的任务状态及任务调度机制，给出了其调度时机及调度算法，并从嵌入式实时操作系统的实时性出发，分析了该调度机制的主要优点。     

单片机与嵌入式系统新书推荐

嵌入式系统词典；嵌入式实时操作系统μC／OS-II原理及应用；ARM嵌入式系统实验教程（二）；ARM微控制器基础与实战（第2版）；源码开放的嵌入式实时操作系统T-Kernel；     

U-Boot 在 MicroBlaze 处理器上的移植方法

在通信干扰系统中,为了分析干扰效果,通常需要对被干扰的信号进行采集和分析.由于文中所涉及的采集系统使用了 Linux 操作系统,因此需要用 Bootloader(引导加载程序)将操作系统加载到采集系统的程序存储器,使系统投入运行.文中主要研究了该信号采集系统的 Bootloader(U-Boot)的移植过程,针对采集系统所使用的硬件修改了 U-Boot 代码的文件,给出了 U-Boot 在移植过程中的详细步骤和修改要点,并对 U-Boot 启动后的采集系统进行了验证.结果表明,文中所移植的 U-Boot 程序可以正确引导 Linux 操作系统,并且能够提供操作系统所需参数,解决了该数据采集系统的操作系统无法加载的问题.文中的工作不仅为 FPGA 器件在嵌入式系统中的应用提供了一个较好的解决方案,同时文中所述的移植过程为相关的嵌入式系统设计人员提供了一定的参考.     

源代码公开的实时嵌入式操作系统μC/OS-II在TMS320LF2407上的移植

介绍了嵌入式操作系统μC/OS-II在DSP芯片TMS320LF2407上的移植.对其中移植的要点和难点进行了分析,给出了比较详细的移植过程,最后在所移植的系统上创建了两个简单任务.     

基于PowerPC处理器SMP系统的U-Boot移植

引导加载程序是计算机系统加电后运行的第一段程序代码,负责系统硬件的初始化和加载操作系统,它和系统硬件结构密切相关.本文针对一个基于PowerPC处理器的对称多处理系统平台,进行了U-Boot移植.并介绍了对称多处理系统的不同之处和移植方法.     

嵌入式Linux的BootLoader在DM6446上的实现

移植引导装载程序(BootLoader)是嵌入式系统开发的关键技术.介绍了BootLoader的特点及其在DM6446平台上的引导方式,分析U-Boot源代码的运行机制,并对U-Boot代码进行修改和调试,最后总结出移植BootLoader的成功经验,详细阐述了U-Boot在DM6446平台上的移植步骤和关键技术.这对DM6446双核处理器上的产品开发有一定的借鉴作用.     

TinyX显示驱动在ARM开发板上的移植

TinyX窗口系统被广泛应用于嵌入式系统,移植TinyX窗口系统的首要任务是显示驱动的移植.对TinyX窗口系统基于FrameBuffer的显示机制进行了分析,以ADV7179作为ARM平台的显示芯片,提出了将TinyX窗口系统的显示驱动移植到该平台上的解决方案,对TinyX窗口系统在不同平台下的移植有很好的借鉴价值.     

eCos在基于MPIS架构Soc上的移植实现

介绍了实时操作系统eCos的特点和开发架构.并通过实现eCos在MIPS32为内核的PNX8310嵌入式系统片上的移植,阐述eCos在嵌入式系统上的移植方法.重点讨论了移植过程中的一些关键点,分析了硬件抽象层的移植方法.该移植方案已经过实际测试,系统稳定可靠.     

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