支持e-Science的网格体系结构及原型研究

提出了e-Science网格的虚拟动态分层体系结构(VDHA).VDHA是具有P2P特征的分散的支持e-Science网格的体系结构.VDHA具有可扩展性、自动性、精确和完全服务发现的特点.实现了基于VDHA的验证原型系统VDHA Grid,其具有可扩展的网格信息服务.VDHA_Grid是中国大学e-Science网格项目的核心软件.也讨论了VDHA的一些优点及相关协议.     

地学e-Science发展的回顾与展望

自 e-Science 提出之后的近 20 年间,地学 e-Science 在计算、网络和存储等信息技术的推动下,业已形成了基于数据、模型、计算、可视化分析和协同工作的地学研究框架,已经成为推动地学研究方法变革的驱动器。本文梳理和归纳了地学 e-Science 的发展过程和一些典型应用,总结了地学e-Science 的发展趋势,提出了简化的基于 3M 平台（Monitoring（监测平台）、Modeling（模型平台）、Manipulating（操作平台））的地学 e-Science 架构。从地学 e-Science 发展趋势上看,建立基于数据产生、采集、传输、管理的联合观测系统,形成完善的监测平台是地学 e-Science 的基础。建立数据分析、制备、同化和模型构建、集成与模拟的模型平台是地学 e-Science 的核心。建立基于高性能计算、可视化分析和协同工作环境的操作平台是地学 e-Science 研究的基本环境。     

网格为研究带来希望

e-Science(第二代英特网的科学资源共享)将使用网络与网格计算创建强大的处理系统,这是科学研究的未来。牛津e-Science中心的教授保罗·杰福瑞说:“网络给了我们分享互联网上信息的能力,网格技术将安全地分享分布式的计算资源。”杰福瑞认为:“e-Science背后的驱动力在于我们需要处理大量科学研究中的数据信息。”现代的科学家已用千兆(petabytes)来测量数据,如果用普通的计算机,他们需要花费数年的时间来对这些数据进行计算。杰福瑞说:“使用网格技术,全球的科学家能够进行协同工作,利用联网的计算机快速地解决问题,并扩大科学知识的界限…     

多移动机器人合作系统中的单机控制体系结构研究

随着机器人技术的不断发展,出现了合作多移动机器人系统这一新的研究和应用领域,随之而来的是对机器人控制体系的新的要求．本文分析了合作多移动机器人系统对单机控制体系结构的要求,并以此为背景,在比较两种典型的智能机器人体系结构的基础上,提出一种混合分层的体系结构     

多移动机器人关键技术研究

本文介绍了多机器人领域研究的关键问题,并对多机器人体系结构、合作协调、路径规划及通信技术进行了详细分析．提出了未来值得研究的关键技术。     

多移动机器人合作系统中的单机控制体系结构研究

随着机器人技术的不断发展,出现了合作多移动机器人系统这一新的研究和应用领 域,随之而来的是对机器人控制体系的新的要求．本文分析了合作多移动机器人系统对单机 控制体系结构的要求,并以此为背景,在比较两种典型的智能机器人体系结构的基础上,提 出一种混合分层的体系结构．     

e-Science应用中野外数据采集传输系统设计与实现

e-Science是近年新兴的研究热点,主要研究IT技术与各学科领域的结合与应用。野外数据的采集与传输是在涉及野外观测的学科领域中开展e-Science应用所面临的亟需解决的问题。提出了一种融合多种通讯方式的支持野外数据采集与传输的系统架构,以实现自动化、高效的数据采集与传输。提出的系统已经使用JAVA语言开发出了原型系统,经过测试有较好的实用效果。     

网络信息系统的生存性体系结构研究

系统体系结构的研究是设计和实现任何实际系统的基础。该文对生存性网络信息系统的体系结构及其相关概念进行定义,明确生存性网络信息系统体系结构的设计原则,分析生存性网络信息系统的运行机制,说明生存性特性的作用,并构建3+2模式的生存性网络信息系统体系结构。实际运行结果表明了该结构的有效性。     

高层体系结构与多智能体仿真集成研究

对于复杂大系统的建模与仿真,多智能体系统可以提供并行逻辑的支持,而高层体系结构(HLA)则可以提供公共的技术框架.两者的结合能有效地提高系统仿真与建模的效果,但是HLA/RTI的规范对多智能体系统的灵活性与开放性有一定的限制,不能充分发挥智能体在推理交互和协商合作等高层次通信方面的优秀特性.在高层体系结构下利用JADE平台工具对多智能体仿真环境进行了研究,提出了集成系统的总体架构和具体方法,并建立了原型系统,通过实验验证了集成方案的可行性,为进一步的研究奠定了基础.     

时间敏感目标打击系统体系结构研究

时间敏感目标的打击能力主要是指对战场上稍纵即逝的目标实施快速打击的能力.时敏目标打击系统是一种战场指控模式的系统,是实现时间敏感目标打击的工具,而体系结构是设计时敏系统的一个基础蓝图.文中首先阐述了时间敏感目标打击系统的特点及能力,其次介绍了体系结构发展历史,最后设计了美军在时敏目标打击系统的体系结构方向研究动向,对时间敏感效能作战体系结构进行了探讨.该体系结构的设计对时间敏感目标打击系统的研究起到一定指导作用     

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。     

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.     

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.     

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.     

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.     

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.     

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。     

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.