一种基于本体的异构数据源模式集成

本体是概念模型的明确的规范说明,能够精确地描述概念体系和领域知识。为了将异构数据源中的数据识别出来并进行语义相关的集成,提出了一种基于本体集成异构数据源的方法。首先将各个数据源中的数据以XML文档形式进行描述,然后将各个XML文档的文档类型定义(DTD)转化为DIM数据模型表示,最后通过语义聚类、全局模式生成等步骤,实现XML文档的基于本体的语义集成。文中提出的方法以普林斯顿大学的心理学家、语言学家和计算机工程师联合设计的一种基于认知语言学的英语词典为本体库,可有效地识别出异构数据源中的具有等价语义或相近语义的数据,从而更准确地对异构数据源中的数据进行集成。     

异构专利数据源集成系统中查询的研究

为了有效地对异构专利数据源进行统一的查询,提出一个基于本体的异构专利数据源集成系统.该系统引入本体解决数据源集成中存在的语义异构,通过全局数据模式为用户提供统一的查询接口,将用户针对全局数据模式的查询重写为针对各个局部数据源的子查询.使用该系统,用户可以从异构的专利源中得到正确的查询结果.     

基于本体的XML语义集成研究

针对具有相同语义的XML数据经常具有不同表达形式的问题,采用了基于本体的语义集成方法来集成异构XML数据源,即通过一系列映射规则将XPath的局部路径与本体关联起来,将用户的RDQL查询重写为基于XML的XQuery查询,从而达到语义集成的效果。本方法的意义在于用户可以通过本体查询异构的XML数据源。     

一种基于Ontology的数据集成系统

针对异构数据源中实现基于语义的数据集成的需求，采用分层思想，在用户层与实际数据层之间增加一个中间层来屏蔽底层数据的异构，用本体作为公共语义描述工具，建立本体到各数据源的映射规则，设计实现了将基于本体的全局查询转化为基于各数据源的局部查询系统，解决了数据源之间的语义异构问题，其中用OWL表示本体和映射，并研究了系统中的关键技术。     

基于本体的异构数据集成的研究

随着计算机技术的发展,很多企业内部实现了信息的计算机管理,积累了大量的数据.这些数据存在异构现象,相互之间难以集成和共享.传统的数据集成方法已经不能适应企业获取信息的需求,迫切需要一种新的数据集成系统.在XML技术基础上,提出一种基于本体的异构数据集成系统,用来解决数据源之间的语义异构问题.给出一种基于本体的异构数据集成的系统结构,对关键技术问题进行了研究,指出了系统今后研究的方向.     

基于本体的异构数据源集成系统分析与设计

分析了现有的数据集成方式，针对集成中的语义异构问题提出了一种基于本体和XML的集成系统框架，其中包括应用层、中间件层和数据源层3个层次，并给出了关键模块的设计，包括中介器、本体库和包装器。结合航空装备信息的特点，介绍了该框架在航空装备信息集成系统中的具体应用。     

基于"本体"的异构数据源的集成方法研究

本文给出了一种基于本体的异构数据源的集成方案,该方案从根本上解决了企业内部数据源的语法异构和语义异构;同时,也为企业内部的信息及时而准确地实现共享,提供了一套行之有效的技术措施.     

基于本体的装备领域信息集成研究

装备信息集成中存在着大量的语义异构数据源,阻碍了信息的共享和交换.本体可以描述信息之间隐含的关系.在语义和知识层次上描述信息系统的概念模型,有效地解决信息集成中的语义异构问题.通过对基于本体的信息集成方法的分析,采用Wrapper/Mediator架构,提出了基于混合本体的装备基础信息集成框架,给出了框架的层次结构和关键技术.结合实际对基于本体的装备指标体系构建和查询处理问题进行了研究,验证了基于本体的信息集成方法在装备领域信息集成中的可行性和有效性.     

一种基于XML的数据集成方案及其关键技术

介绍了一种改进的基于XML的数据集成方案，给出了集成系统结构图以厦实现系统所需要的相关技术。方案中将实体法和虚拟法相结合，利用本体（Omology）解决语义异构问题，数据复制方法解决数据的实体化，较好地解决了异构数据源的联合使用问题，提高了数据的查询效率。     

EAI中本体异构数据集成中间件的设计与实现

提出了在企业应用集成EAI(Enterprise Application Integration)中基于本体的异构数据集成中间件,通过使用本体描述语言(OWL)对数据源进行建模,提高了系统集成的灵活性,隔离了数据源模式的变化,使得局部数据源模式的变化不会影响到整个集成系统.此外,通过引入本体来描述数据模式,为解决集成中的语义异构问题提供了支持,解决了数据源异构性问题,以实现灵活的数据源集成能力.     

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.     

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.     

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。