适用于空间环境下的FPGA容错与重构体系

FPGA极大地提高了电子系统设计的灵活性和通用性，被广泛地应用在各个领域。在空间环境中，FPGA 容易受到SEU的影响而导致内部逻辑的紊乱，系统重构与故障恢复也比较困难。该文提出了一种在星载环境下，使用CPLD对FPGA进行基于错误诊断的容错体系结构设计，兼顾到了系统重构与故障恢复，在实验中取得了较好的效果。     

基于三层级低开销的FPGA多比特翻转缓解技术

商用现货型FPGA被认为是解决目前空间应用对处理能力需求不断增加的唯一途径,由于其对多比特翻转的敏感性,需要针对空间应用的单粒子效应采取专门的设计加固技术。提出了基于用户逻辑层、配置存储器层和控制层3个层级的容错技术框架。在用户逻辑层,提出了一种新型的低开销的FTR策略用于用户逻辑的错误检测;在配置存储器级,提出了基于模块和帧的动态部分可重构策略用于处理配置存储器的错误;在控制级,以Xilinx ZYNQ片上系统型FPGA为目标,利用其嵌入的硬核处理器进行基于检查点和卷回体制的电路状态保存和恢复。整个容错技术框架在7级流水的LEON3开源器处理器中进行了故障注入的试验验证,试验结果显示在增加85%的LUT资源和125%的触发器资源使用条件下,99.997%注入的故障得到了及时纠正。     

一种基于体系结构模板的粗粒度可重构SoC设计方法

针对传统的面向应用领域的多核SoC体系结构设计方法存在系统结构探索空间大、设计复杂度高等问题,提出了一种基于体系结构模板的粗粒度可重构SoC系统架构设计方法。该设计方法以体系结构设计为中心,体系结构模板可重用、参数可配置,从而缩小了体系结构设计探索空间,提高了体系结构设计效率,降低了应用程序编译器开发复杂性。最后,以密码处理领域为例,将模板参数实例化,构建了一个面向密码处理领域的多核可重构指令集处理器SoC系统(Multi-RISP SoC)。实验结果表明,MultiRISP SoC系统与几个典型可重构平台在性能上相当,但系统构建更为快速高效。     

基于函数级原型的流水线可重构结构的研究

针对目前动态可重构技术中重构时隙的问题,本文利用流水线技术和可熏构技术,提出并讨论一种流水线可重构体系结构的函数级原型设计方法,并采用AES算法对其进行了仿真验证.结果表明,流水线可熏构结构的函数级原型设计方法可有效的解决动态重构系统中的重构时隙问题.     

多核处理器可重构Cache功耗计算方法的研究

多核动态可重构Cache是解决Cache功耗困扰的一个重要方法。现有Cache功耗模拟器并不能很好地支持多核动态可重构Cache功耗研究,通过对多核动态可重构Cache的功耗模型进行研究,找到了计算可重构Cache的方法和思路,应用CACTI来分别构建各个组成结构的Cache功耗模型,以较为准确地测算可重构Cache的功耗。在Simics模拟器下构建动态可重构Cache,运行测试程序,对比传统的体系结构,可重构Cache的功耗能够得到10.4%的降低。同时,实验中发现功耗的降低不仅仅是动态可重构Cache贡献的,而是由系统综合产生的,因此在低功耗设计中,要综合考虑整体系统的功耗和性能,避免片面地考虑Cache结构而导致整体功耗的提高。     

基于HLA的空战仿真系统设计与实现

针对空战仿真应用背景,在对各功能模块进行需求和能力分析的基础上,以组件重用和系统可扩展为目标,设计了一种基于HLA的作战仿真系统体系结构,完成了兵力生成、雷达模拟、视景仿真、数据记录回放等联邦成员开发,并对仿真开发过程中所涉及的雷达模拟等天键技术进行了研究.通过仿真实验验证了所构建仿真系统的可行性.利用该仿真系统可对跟踪算法进行验证,为相关理论的研究提供了分析和验证平台.片对其它领域内基于HLA的仿真系统设计和开发具有参考价值.     

基于HLA的空间光学探测仿真系统设计

为支持星载光学相机的设计论证以及更好的发挥其在空间探测领域的应用需求,设计了一种基于HLA的分布式空间光学探测仿真体系.在对仿真任务进行分析的基础上,进行仿真系统各模型的建模,并以组件重用性和系统可扩展性为目标,运用HLA分布式技术设计了系统的体系结构,最终实现了整个联邦的开发.该系统能够为不同类型的光学载荷、不同轨道姿态控制方式的卫星平台、不同类型目标及背景环境等提供仿真服务.最后,以探测目标卫星为例,表明了该仿真平台的可行性,为进一步研究星载光学相机以及其在空间探测领域的应用提供了良好的仿真支撑环境.     

一种基于过程级编程模型的可重构片上系统设计方法

可重构片上系统是一种兼具功能灵活性与高运算速度的新型计算平台,是面向未来嵌入式应用市场复杂需求的技术解决方案,但复杂、困难的设计过程必将阻碍它的广泛应用与进一步发展.针对当前可重构片上系统设计过程中编程不透明、可重构资源难以有效利用等问题,结合可编程器件能够根据应用特性动态配置芯片体系结构的特点,提出并实现了一套基于过程级透明编程模型的软硬件协同设计方法.在编程模型框架内,系统设计人员通过调用已根据应用特性进行优化的软硬件协同函数库,即可利用高级语言完成系统功能描述;动态软硬件划分算法在程序运行时对其进行划分,选择、调度需要转换到软件或硬件实现的库函数,并通过动态链接器实时切换函数的运行方式,从而形成一个由功能描述到系统实现的自动化流程.实验及测试结果验证了该方法的可行性和高效性.     

可重构片上系统设计流程中的动态重构问题研究

近年来,可重构片上系统已成为科学研究及嵌入式应用领域中应对复杂计算需求的有效技术解决方案.针对目前缺少一个从系统级设计到应用实现,统一、综合规划动态重构问题的系统设计流程,以及动态重构过程对系统设计人员不透明等问题,在系统设计层给出了一种过程级软硬件统一编程模型.在此框架内,设计人员通过调用已根据应用特性进行优化的软硬件协同函数,即可利用高级语言完成系统功能描述;在细节设计层提出了基于单位面积加速比的软硬件任务调度算法,实时管理动态可重构资源;在应用实现层,以可重构专用图形加速卡为原型系统,论述动态可重构系统实现中的关键技术.实验及测试结果验证了通过将动态重构问题置于整个系统设计流程中予以考虑,能够达到提升系统开发效率之目的.     

基于设计模式的星载软件体系结构设计方法

星载软件是整个卫星系统设计和开发的中心,而体系结构是整个软件开发的蓝图,在软件开发中占有十分重要的位置。为了提高星载软件开发效率,降低研制成本,同时满足实时性、可重构和可维护性要求,从体系结构的前3个视图方面采用基于设计模式的方法提出了一种满足要求的星载软件体系结构。     

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。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。