基于领域本体的贝叶斯网络检索模型研究

针对传统的信息检索方法无法实现用户查询的语义理解、检索效率低等问题,本文提出基于领域本体进行查询扩展的贝叶斯网络检索模型。该模型首先将用户查询通过领域本体进行语义扩展,然后将扩展后的查询作为证据在贝叶斯网络检索模型中进行传播,进而得到查询结果,实验表明本文提出的贝叶斯网络检索模型能提高检索效率。     

一种基于本体和用户日志的查询扩展方法

为了解决信息检索中存在的用词歧义性问题,提出一种基于本体和用户日志的查询扩展方法。利用领域本体从语义层面扩展用户查询形成初始扩展概念集,结合用户查询日志利用共现度分析对初始扩展概念集进行二次筛选。实验结果表明,与传统的基于局部共现的扩展方法和基于本体的扩展方法相比较,该方法在保障良好鲁棒性的同时,有效地提高了检索准确率。     

基于领域本体的语义查询扩展

在信息检索研究领域,资源与查询词的匹配决定信息检索质量。现有检索方法的检索结果存在过多不相关信息,不能很好满足用户需求。针对传统信息检索存在的问题与当前语义查询扩展方法的特点,本文在分析各种语义查询扩展方法及其相关研究的基础上,提出一种改进的基于领域本体的语义查询扩展方法。该方法论通过本体模型和概念相似度的计算对检索信息进行检索意图树的构建并扩展;然后在资源本体中以最短路径的方式搜索资源。实验结果表明,本文方法相较其他查询扩展方法能得到更好的检索结果。     

基于本体的林业领域语义查询扩展模型

传统信息检索模型仅考虑考虑关键词本身的匹配程度,在林业领域信息检索时得到的检索结果不全面或不准确.为了改善检索质量,提出了一种基于本体的林业领域语义查询扩展模型.该模型利用了本体的语义推理的能力和语义结构对关键词进行语义查询扩展,最终实现提高检索查全率和查准率的目的,是对传统基于关键词匹配的信息检索模型的语义补充.结果表明该模型在一定程度上改善了林业领域信息检索结果的查准率和查全率.     

基于领域本体的智能检索模型

在传统检索模型的基础上,结合本体概念,提出一种基于领域本体的检索模型。该模型利用本体中语义概念关系及语义扩展机制对查询关键词进行概念映射及扩展,通过计算文档相似度返回检索结果,提高检索的查准率和查全率。     

本体技术在语义博客中的应用研究

研究了本体描述语言OWL,提出并实现了一个基于本体和Lucene的语义检索模型,利用领域本体知识库对用户的查询要求进行语义扩展,构建了具有全文检索和语义检索功能的语义博客系统。实验证明语义检索方案在运行效能上可行,并且可以提供更高的查准率和查全率,对改进当前的检索系统是具有一定积极意义的。     

基于推理的语义网检索模型及关键技术研究

为解决语义网检索过程中缺少推理导致语义检索性能不高的问题,提出一个基于推理的语义网检索模型,并介绍了该模型实现的关键技术.针对构建的领域本体,使用SWRL规则语言进行本体完善把本体中的隐性知识表示出来;在信息抽取过程中,对于识别出的实体,利用推理规则,获得更加丰富的实例知识库;对于用户输入的查询条件,利用完善的本体知识库及规则得到更多的相似概念实现查询扩展;进行语义匹配,获得更为精准的检索结果.实验结果表明,该模型能提高信息检索的语义性,得到较满意的信息检索结果.     

云计算下支持语义的可搜索加密方法研究

传统的云计算下的可搜索加密算法没有对查询关键词进行语义扩展,导致了用户查询意图与返回结果存在语义偏差,并且对检索结果的相关度排序不够合理,无法满足用户对智能搜索的需求。对此,提出了一种支持语义的可搜索加密方法。该方法利用本体知识库实现了用户查询的语义拓展,并通过语义相似度来控制扩展词的个数,防止因拓展词过多影响检索的精确度。同时,该方法利用文档向量、查询向量分块技术构造出对应的标记向量,以过滤无关文档,并在查询-文档的相似度得分中引入了语义相似度、关键词位置加权评分及关键词-文档相关度等影响因子,实现了检索结果的有效排序。实验结果表明,该方法在提高检索效率的基础上显著改善了检索结果的排序效果,提高了用户满意度。     

一种基于本体的视频检索技术研究

传统的视频检索大多采用基于关键词的方法,难以获得让用户满意的查准率和查全率。为此提出一种基于本体的视频检索技术,该技术借助于领域本体,以其基本概念为关键词通过互联网图像搜索引擎在线获取样本图像组,提取SIFT特征建立图像特征词典,抽取图像特征直方图并计算相似度,辅助完成视频的自动标注,初始化视频检索库;同时,借助于领域本体,对从用户的查询输入中抽取的关键词进行语义扩展,将以扩展概念集进行检索的结果返回给用户,以此实现基于本体的视频检索。最后,结合实例对该算法进行实现和分析,表明了该方法的可行性和有效性。     

基于本体和局部上下文分析的查询扩展

在信息检索过程中,因查询词短少而引起的检索歧义性是影响检索效率的主要原因之一,而查询扩展方法和本体扩展方法能有效改善这一问题.提出一种基于本体和局部上下文分析的查询扩展方法:本体扩展根据本体推理规则对短查询词进行推理,得到与查询词有逻辑关联的推理结果集,为查询词加入了标准化的关联信息.局部上下文分析通过对文档库的分析,在与用户查询词最相关的前m篇文档中抽取与用户查询词最相关的n个扩展词,为查询词加入了统计扩展信息.将两部分扩展查询词合并,再通过扩展查询词相关度计算对搜索结果集进行排序.该方法结合了这两种方法的各自优势,从语义角度扩展关键词.实验分析表明,该方法能有效提高检索查全率和查准率.     

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.