基于用户兴趣偏好的网络文档检索

本文提出了一种基于用户兴趣偏好的网络文档检索策略。用户长期浏览网页的过程中搜集用户的兴趣偏好特征值,并将表达用户偏好的关键词按序排列,以语义关联度为标准对每次搜索引擎的网页排序结果进行重排,并在此过程中充分考虑用户偏好信息的保护。用户兴趣偏好特征值通过用户的浏览反馈行为对自身进行动态修改,使其不断捕获变化着的用户兴趣热点。实验表明,基于用户兴趣偏好的网络文档检索策略较传统的文档检索在召回率、准确率等性能指标上有所提高。     

基于条件偏好的XML查询结果排序方法

摘要为了解决XML查询的信息过载问题,提出了基于条件偏好的XML多查询结果排序方法。该方法把用户指定的内容查询谓词作为上下文条件,然后在原始XML数据和查询历史上利用概率信息检索模型推测当前用户偏好,评估结果元素中被查询指定的属性单元值与未指定的属性单元值之间的关联关系以及未指定的属性单元值与用户偏好之间的相关程度,进而构建查询结果元素打分函数;在此基础上,利用打分函数计算结果元素的排序分值,并以此对查询结果进行排序。实验结果表明,提出的排序方法具有较高的排序准确性,能够较好地满足用户需求和偏好。     

基于粗糙集的个性化Web搜索系统

本文提出了一种基于粗糙集理论的个性化web搜索系统。用户偏好文件中对关键字进行分组以表示用户兴趣类别。利用粗糙集理论处理自然语言的内在含糊性,根据用户偏好文件对查询条件进行扩展。搜索组件使用扩展后的查询条件搜索相关信息。为了进一步排除不相关信息,排序组件计算查询条件和搜索结果之间的相似程度,根据计算值对搜索结果进行排序。与传统搜索引擎进行了比较,实验结果表明,该系统有效地提高了搜索结果的精度,满足了用户的个性化需求。     

基于检索历史上下文的个性化查询重构技术研究

基于检索历史隐式地学习用户偏好是个性化检索研究的热点,而根据用户检索历史重构新的查询输入是其中主要的研究内容。已有的研究在利用检索历史进行查询重构时,通常不区分检索历史中的内容是否与当前查询相关,而是将全部检索历史视为整体,因而使重构后的查询含有较多噪声。该文基于相关词语在上下文中大量共现的特征,将用户历史检索结果的网页摘要作为上下文语境,结合用户点击,选择检索历史中与当前查询共现程度最高的词语重构查询模型。对初始检索结果重排序的实验表明,该方法可以有效地选择相关词语,减少噪声。用p@5和NDCG两种指标评价,比最好的基准系统分别相对提高12.8%和7.2%,比初始排序结果相对提高 26.0% 和11.4%。     

基于用户兴趣特征提取的推荐算法研究*

传统的推荐算法一定程度上降低了网络消费者的搜索成本,但难以实时提供消费者满意的推荐服务,也忽略了用户偏好动态转移性。为了提高电子商务系统的推荐质量,从用户偏好的行为特征入手,建立了网络用户的兴趣特征提取模型,并设计了相应的推荐算法。通过对用户兴趣特征提取模型的检验和用户兴趣度矩阵的建立,依据与目标用户偏好相似的邻居用户对商品的兴趣程度预测用户对未浏览商品的兴趣度,并选择兴趣度值较高的N个商品推荐给用户。实验结果表明,在用户偏好动态转移的情况下,所设计的推荐算法的推荐精度和推荐效率明显提高,提高了网络用户的     

面向个性化站点的用户检索意图建模方法

针对个性化站点较少考虑用户检索意图的问题,提出结合交叉信息熵和词语特征信息的关键词提取方法以及结合余弦相似度和加权海明距离的文本排序方法,旨在不需要用户任何反馈的条件下,为用户推荐更满意的检索结果。通过过滤用户请求个性化站点时的访问地址,获取用户浏览的网页文本内容,从中提取能够表示用户检索意图的关键词集进行重新检索后对检索结果排序,最后将排序后的结果作为推荐模块返回给用户。实验表明,利用该方法获得的查询推荐结果能够更加符合用户检索意图,提供更好的用户体验。     

一种长短期兴趣结合的个性化检索模型

个性化信息检索针对用户个人兴趣优化文档排序,被认为是改善用户检索体验的一种有效途径。为提高个性化检索模型的检索性能,该文提出了一种将用户的长短期兴趣结合的通用方法,利用用户长期兴趣和短期兴趣对查询模型进行改进。大规模真实搜索日志数据上的实验结果显示,利用长短期兴趣能够获得准确表达信息需求的查询模型,相对于传统的个性化检索模型取得了更好的效果。
     

基于查询片段松弛的XML小枝近似查询方法

为了解决普通用户对XML文档的近似查询问题,提出一种基于查询片段松弛的XML小枝近似查询方法.该方法利用查询历史推测用户偏好,进而根据用户偏好为原始小枝查询中的每个查询片段分配重要程度,然后基于查询片段重要程度对原始小枝查询条件进行松弛处理,最不重要的查询片段最先松弛,从而确保获取最为相关的查询结果;最后,根据对原始查询和用户偏好的满足程度,将得到的满足松弛查询条件的结果进行排序.实验结果表明,本文提出的查询松弛和结果排序方法能够获得较高的查全率和准确率,并且能较好地满足用户需求和偏好.     

基于上下文偏好的Web数据库查询结果Top-K排序方法

为了解决Web数据库多查询结果的问题,该文提出了一种基于上下文偏好的查询结果top-k排序方法,首先提出了一种带偏好程度的上下文偏好模型:i_1i_2,d|X,表示在上下文条件X下,项i_1与i_2相比,用户偏好项i_1的程度为d(0.5≤d≤1),带偏好程度的上下文偏好通过在查询历史中使用关联规则挖掘获得.基于上下文偏好,提出了一种查询结果top-k排序方法,给出了相应的元组排列创建、聚类和top-k排序算法.实验结果表明,提出的上下文偏好模型具有较强的偏好表达能力,top-k排序方法能够较好地满足用户需求和偏好并且具有较高的执行效率.     

基于 HowNet 的用户兴趣挖掘研究及应用磁

搜索引擎中用户查询和网页资源之间的相似度研究一直是页面排序的研究核心。利用 HowNet 对词语的语义层次架构模型,对用户的检索词进行兴趣挖掘,同时对检索词和挖掘出的兴趣关键词的语义相似度计算方法进行改进,用户的检索请求与分块后的网页资源进行相似度迭代计算。实验结果表明,改进的算法使得页面排序的准确率和首页命中率有了较大提高。     

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.