XML数据压缩技术的研究进展

XML的自描述特性使得XML数据中存在大量冗余信息。如何压缩XML数据以提高XML数据管理的效率成为一个新的研究领域。从2001年起,XML数据压缩技术的研究已经取得了很多研究成果。从面向存储的XML数据压缩技术、面向查询的XML数据压缩技术和面向特定应用的XML数据压缩技术三个方面综述了XML数据压缩技术的研究进展,讨论了目前存在的主要问题和需要进一步研究的方向,并提供了广泛的参考文献。     

基于XML的数据管理技术

随着Web技术的快速发展,如何有效地存储、索引、查询和显示XML数据已经成为数据库研究领域的一个热点研究问题。本文介绍了XML数据的3种不同存储方法;XML搜索查询的工具和语言;XML数据的访问控制模型;XML最直接的显示方法以及正在实现的真正的XML数据库等。通过这些XML数据管理技术,可以了解到当下XML研究领域的先进技术和方法,指导今后的研究方向和重点。     

基于Hibernate的XML数据操作方法研究

随着Web技术及其应用的快速发展,XML已经成为互联网上信息表示和数据交换的一个重要标准。当前,学术界对于XML数据管理的研究。其内容广泛。如XML数据存储、XML数据查询、XML索引、NativeXML数据库、XML流处理、XML数据发布等。Hibernate允许将XML数据映射到实体模型中．这样就可以使用一般的会话方法访问XML数据。     

XBackend:一种Native XML数据库系统的后端实现策略

随着XML技术研究与应用的深入,涌现出了大量XML文档.为了对XML文档进行管理和查询,大多数RDBMS扩充了处理XML数据的功能.这种方式将XML数据映射到关系表中,会破坏XML数据的树型结构.查询时,需要多次的表连接,降低了查询效率.原生XML数据库以XML文档作为基本的逻辑存储单位,建立底层的物理存储模型.提出了一种原生XML数据库的后端实现策略--XBackend,包括存储策略、索引策略、数据库恢复策略. XBackend底层存储是专门为XML数据设计的,配合适当的索引,具有更高的存储和查询效率.数据库恢复策略保证了原生XML数据库数据的一致性状态.实验结果表明XBackend具有很好的性能.     

基于XML的数据库存储访问技术

随着XML日益普遍应用,如何有效地存储和访问XML文档中的数据已成为亟待解决的关键问题。讨论了目前比较先进的XML技术和基于XML的数据库模型,依据该模型和微软的SQL Server 2000实现XML数据的存储和访问。举例说明了如何在SQL Server中实现XML访问和XML存储。     

基于SAX的XML解析与应用

随着XML的广泛应用,大量的信息都将通过XML文档来进行存储、交换,因此熟悉和掌握一种解析XML文档的方法是很重要的.通过介绍基于SAX的XML解析的原理、特点、实现及在数据存储方面的应用,并与DOM技术进行比较.突出XML存储数据的优点,对推广应用XML及其解析技术有一定的实用意义.     

基于XML数据库的Web应用研究*

使用XML作为数据库存储数据,是XML应用的重要领域。讨论了如何用XML数据库系统进行Web应用开发设计的相关技术,如XML数据库、XML文档及其有效性定义、数据转换链接和Web平台搭建等。     

XML技术在图形数据库中的应用

XML技术具有良好的数据存储格式、可扩展性、高度结构化、便于网络传输等4大特点，由于XML能针对特定的应用定义自己的标记语言，使得其在各个行业的应用具有开创性。该文采用XML作为基础，建立了一个图形数据库系统，该系统采用了XML的体系结构和实现方法，对于图形数据的网络化存储以及数据库连接、数据查询都作了实现性开发，实践证明XML技术是可行的。     

基于原生数据库的SaaS存储模型

SaaS应用中的多租户数据存储是当前的热门研究点, 现有解决方案大都基于关系数据库, 采用模式映射技术. 从SaaS的存储灵活性和分布式特点分析了使用原生XML数据库的可行性, 并给出了适合多租户数据的XML存储结构, 能够有效支持SaaS的上述特点.     

Oracle XML DB和DB2 pure XML在XML文档存储查询性能方面的比较分析

可扩展标注语言XML在计算机软件的数据接口定义中有着广泛的应用。分析Oracle XML DB和DB2 pure XML关于存储和查询XML文档的技术特点及其实现原理,并通过测试比较,分析这两种技术在存储和查询效率上的差异。在相同XML文档存储负荷下,Oracle XML DB与DB2 pure XML关于存储和查询的耗时之比分别约为2∶1和1.32∶1。     

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。