主题Web挖掘研究

网络已经成为人们获取知识的一个重要途径。然而面对巨大的Web资源库,用户若想获得所需要信息已不再是一件简单的事情。通用搜索引擎返回大量的无关信息．不能满足用户的特定信息检索需求。针对这个问题,Web信息检索领域出现了一个新的研究方向——主题驱动的Web资源发现。介绍了通用搜索引擎的基本结构、工作原理及现状。阐述了主题Web挖掘的研究背景、任务及目前研究技术的进展,并对其未来的发展方向进行了探讨。对通用搜索引擎和主题Web挖掘的关系进行了分析。     

基于XML和ANN的Web文本智能检索研究

传统的网络信息检索技术如搜索引擎存在一些不足,一方面它只是将信息搜寻出来,不能发现隐藏在数据背后的知识;另一方面其采集软件在采集数据时缺乏人工干预,智能性不强,导致信息利用率不高.针对传统的Web搜索引擎存在的上述问题,结合Web文本挖掘、XML、BP神经网络在数据处理方面的长处,提出了一个具有一定智能的Web文本信息检索模型,以使其具有较高的信息利用率.     

面向主题的Web信息收集系统的设计与实现

随着互联网信息的持续爆炸性增长，通用搜索引擎的信息覆盖率和检索精度都在不断下降，发展面向主题信息的专用网络信息检索工具已经成为趋势。文中提出的面向主题的Web信息收集系统是这类工具的核心部件，该系统采用文档矢量模型进行文档相关度计算，并结合页面链接的上下文信息过滤页面；借鉴并修改了Shark启发式查找算法来查找相关页面；可采用多机并行下载提高收集效率；并依据站点的重要程度进行动态更新。在一个面向Internet的计算机教学资源检索的搜索引擎中具体实现了这个Web信息收集系统，整个系统在低性能的台式机上就能运行，并可获得较高的属于指定主题的页面的收集精度和收集效率。     

基于语义的Web信息检索

用户要从网络中得到所需的信息一般是通过各种搜索引擎。但是现有的搜索引擎都存在着检索相关度不高等问题。随着语义Web概念的提出及相关技术的发展,基于语义的Web信息检索逐渐成为了语义Web研究的热点。给出了传统搜索引擎存在的问题,从理论上分析了如何将语义Web技术融入Web信息检索中去,并在理论分析的基础上给出了基于语义的Web信息检索的模型。     

基于语义的Web信息检索

用户要从网络中得到所需的信息一般是通过各种搜索引擎。但是现有的搜索引擎都存在着检索相关度不高等问题。随着语义Web概念的提出及相关技术的发展，基于语义的Web信息检索逐渐成为了语义Web研究的热点。给出了传统搜索引擎存在的问题，从理论上分析了如何将语义Web技术融入Web信息检索中去，并在理论分析的基础上给出了基于语义的Web信息检索的模型。     

面向电子商务的Web挖掘技术及其应用研究

电子商务过程中企业和组织面临一系列网络信息的获取问题,对解决这些问题的Web内容挖掘、Web结构挖掘、Web使用挖掘技术进行了综述,并介绍了Web挖掘技术在智能搜索引擎、企业危机管理、客户关系管理及个性化服务系统中的应用。     

Excite搜索引擎

随着Web在Internet上的迅速发展，各种Web信息检索工具先后涌现，信息查询服务的数量和种类也不断增加，如搜索引擎、Web指南、黄页及白页数据库查询服务等。在大家所熟悉的搜索引擎中，Excite无疑是一个独具人性化和亲切感的搜索引擎。概况Excite检索引擎Web服务器的URL为：http：／／www．excite.com。其总部位于美国加州Redwood城的Excite公司（ExciteInc．），一直致力于自动超文本链接、主题分类和自动文摘的检索查询软件产品、服务及特性的开发，1995年10月推出的Excite搜索引擎是该公司最为著名的整套Web信息服务产品，主要提…     

基于元数据与Z39.50的分布协作式Web信息检索

Web上大量的异质、分布、动态的信息造成了“信息过载”.如何有效地为用户提供Web信息检索已经成为一项重要的研究课题.Web搜索引擎部分地解决了信息检索问题,然而其效果却远远不能令人满意.提出了Web信息检索的分布协作策略以取代传统的集中式信息检索方式;给出了一种新的Web信息检索系统模型,该模型支持对Web文档的元数据进行检索,并采用Z39.50协议作为接口标准,以克服不同信息检索系统之间的访问异构性.在此基础上,设计了一个分布协作式Web信息检索框架,用以帮助用户有效地进行Web信息检索.     

基于主题的Web信息采集系统的设计与实现

基于主题的Web信息采集是信息检索领域内一个新兴且有实用价值的方向，也是信息处理技术中的一个研究热点。文章分析了主题Web信息采集的基本问题，提出了难点以及相关的解决方案，并在此基础上设计实现了“天达”主题Web信息采集系统。     

基于子主题概念的Web主题挖掘

为了帮助用户在Web上查找和编辑具体主题知识,本文给出一种基于子主题概念的挖掘算法。基本思想是：给定一个主题,通过搜索引擎返回的页面集合找出主题的子主题或核心概念,得到包含具体主题及子主题概念的页面,使用户无需浏览所有页面就能获取查询主题系统的、全面的知识。     

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。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.