搜索引擎的工作原理和发展趋势

搜索引擎是一种能够通过Intemet接受用户的查询指令，并向用户提供符合其查询要求的信息资源网址的系统；是网络信息检索的首选工具。目前，各类搜索引擎层出不穷，市场发展需求巨大。因此对搜索引擎技术的研究是很有意义的。本文着重分析了搜索引擎的工作原理以及目前搜索引擎存在的问题，并为解决相关问题提出发展新的搜索引擎模式的建议。     

基于信息类别的元搜索引擎设计

随着搜索引擎技术的发展,元搜索引擎已经成为搜索引擎的一个重要的研究方向.在传统元搜索引擎中,每次查询项提交给元搜索引擎时,元搜索引擎会选择同样的成员搜索引擎、查询项预处理算法和查询结果融合算法.这种处理方法仅考虑到用户的查询项,而没有考虑到用户所需信息的类别.这篇论文介绍了一种基于信息类别的元搜索引擎,对于用户提交的相同查询     

分布式多搜索引擎系统的研究与实现

随着Internet的迅速发展,传统的搜索引擎在覆盖度、查询精度、可扩展性和用户多样化需求等方面存在许多不足.本文详细介绍了多搜索引擎技术,以及在该技术基础上实现的多搜索引擎系统.多搜索引擎系统通过集成目前流行的多个搜索网站,提供更强大的搜索功能,帮助用户更快速更有效地获得所需信息.     

基于移动互联网日志的搜索引擎用户行为研究

随着移动互联网的迅速发展,移动搜索用户大规模增加,移动搜索引擎用户行为分析对改进搜索引擎性能,提高用户体验具有重要意义。该文选取某移动搜索引擎2011年6月第一周的日志,对移动互联网用户搜索行为进行分析和研究。我们从查询词分析、会话分析以及用户点击分析3个角度出发,对查询词长度和频度、问题式查询和网址查询比例、会话内查询个数、查询词修改方式以及用户点击位置进行研究,并与互联网搜索引擎相应指标进行对比。相关分析结论对于移动搜索引擎算法改进与系统优化具有一定参考意义。     

个性化搜索中的用户兴趣模型研究

研究目的是挖掘搜索引擎中用户兴趣偏好,实现个性化搜索引擎技术.研究方法采用识别用户输入查询串,通过查询进行挖掘用户兴趣类别,但有时用户输入查询串短,或者出现查询词歧义等.由于查询会返回一系列文档,将相关文档分类处理,能够更清晰识别用户兴趣偏好.结果显示通过文档关系矩阵,将用户查询映射到对应类别,发现用户兴趣爱好.对于兼类查询等问题可以通过扩展查询解决.结论是该模型通过查询串和相关文档之间关系,进而实现用户偏好的辨别.该技术为搜索引擎信息推荐等技术打下良好基础.     

分布式多搜索引擎系统的研究与实现

随着Internet的迅速发展,传统的搜索引擎在覆盖度、查询精度、可扩展性和用户多样化需求等方面存在许多不足。本文详细介绍了多搜索引擎技术,以及在该技术基础上实现的多搜索引擎系统。多搜索引擎系统通过集成目前流行的多个搜索网站,提供更强大的搜索功能,帮助用户更快速更有效地获得所需信息。     

网络搜索引擎的用户查询分析

利用教科网搜索引擎“网络指南针”的查询记录,就其中102439个用户的810396次查询,在用户查询方式、查询表达表达以及查询词3个层次上,对用户查询行为进行了分析,得到了搜索引擎用户查询的一般规律。根据上述结论对搜索引擎的进一步发展进行了讨论。     

一种基于用户标记的搜索结果排序算法

随着计算机网络的快速发展,网络上的信息量也日益纷繁复杂.如何准确、快速地帮助人们从海量网络数据中获取所需信息,这是目前搜索引擎首要解决的问题,为此,各种搜索排序算法应运而生.但是目前,网页信息的表达形式都十分简单,用户描述查询的形式更是十分简单,这就造成了在判断网页内容与用户查询相关性时十分困难.首先对现有的搜索引擎排序算法进行了分类总结,分析它们的优缺点.然后提出了一种基于用户反馈的语义标记的新方法,最后采用多种评估方法与Google搜索结果进行对比分析.实验结果表明,利用该方法所得到的排序结果比Google的排序结果更接近用户需求.     

元搜索引擎的现状与发展

元搜索引擎利用现有的独立搜索引擎的查询性能,将搜索引擎看成一个整体,为用户提供一个统一的查询界面与返回结果。介绍了目前网络上比较著名和流行的一些元搜索引擎,对近几年来关于元搜索引擎的研究进行了分析总结,旨在为对元搜索引擎的进一步研究提供参考。     

元搜索引擎的个性化调度算法

元搜索引擎的调度算法是研究如何从庞杂的独立搜索引擎中选择出与查询字串相关度最高、与用户的查询需求最贴近的合适数量的独立搜索引擎。现在,在原有的元搜索引擎调度算法基础上,提出了一种个性化调度算法。该算法根据用户兴趣类对所有独立搜索引擎进行文档分类,然后根据用户查询串所属的兴趣分类,计算出查询串与该分类下文档的相关度这一调度算法的主要影响因素,再结合成员搜索引擎的平均响应时间性能评价,返回结果数量,以及以用户反馈为基础的用户兴趣度经验,计算出独立搜索引擎的排序,从而实现个性化的调度。     

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.