基于网站结构分析页面信息提取的方法研究

在分析网站结构的基础上,把同类信息划归为一个页面组,建立相应的XML模板库,进行web信息挖掘,为实现页面信息快速查询和信息分类提供了很好的方法。     

基于表格语义的Web信息抽取方法的研究

在Web页面常用到表格这种元素。本文提出一种根据表格语义来进行信息抽取方法。首先提出了一种短语语义相似度的度量方法,然后利用短语语义的相似度确定表格标题行(列),并对表格行(列)与抽取字段的对应关系进行计算,最后计算表格的整体语义,度量该表格与所要抽取的内容有多大相关度。     

Prefetching in Content Distribution Networks via Web Communities Identification and Outsourcing

Content distribution networks (CDNs) improve scalability and reliability, by replicating content to the “edge” of the Internet. Apart from the pure networking issues of the CDNs relevant to the establishment of the infrastructure, some very crucial data management issues must be resolved to exploit the full potential of CDNs to reduce the “last mile” latencies. A very important issue is the selection of the content to be prefetched to the CDN servers. All the approaches developed so far, assume the existence of adequate content popularity statistics to drive the prefetch decisions. Such information though, is not always available, or it is extremely volatile, turning such methods problematic. To address this issue, we develop self-adaptive techniques to select the outsourced content in a CDN infrastructure, which requires no apriori knowledge of request statistics. We identify clusters of “correlated” Web pages in a site, called Web site communities, and make these communities the basic outsourcing unit. Through a detailed simulation environment, using both real and synthetic data, we show that the proposed techniques are very robust and effective in reducing the user-perceived latency, performing very close to an unfeasible, off-line policy, which has full knowledge of the content popularity.     

Using Wide Table to manage web data: a survey

With the development of World Wide Web (www), storage and utilization of web data has become a big challenge for data management research community. Web data are essentially heterogeneous data, and may change schema frequently, traditional relational data model is inappropriate for web data management. A new data model, called Wide Table (or WT for simplicity), was introduced for this task. There are several characteristics of the WT model. First, WT is usually highly sparsely populated so that most data can be fit into a line or record. Second, queries are composed on only a small subset of the attributes. Thus, existing query processing and optimization techniques for relational database with normalized tables will not work efficiently anymore. Furthermore, WT is usually of extremely large volume. It is thought that only large-scale distributed storage can accommodate themassive data set. In this paper, requirements and challenges to web data management are discussed. Existing techniques for WT, including logical presentation, physical storage, and query processing, are introduced and analyzed in detail.     

Learning about psychological professions with the world-wide web

Abstract Teaching with the world-wide web is becoming a common practice in modern education. The web serves two main interrelated functions, namely, retrieval and publication of information. To enhance learning and motivation, the student-as-teacher (SAT) principle was adopted in the study reported in this paper. Students were given the role of teacher of high school students and the general public about the subject matter they learned on a course. To achieve this goal, the students created educational web sites featuring two selected psychological professions. Being the major assignment for the course, the web sites created by students received higher scores than the assignments of their peers who learned the same materials through traditional pedagogical approaches. Course evaluation confirmed that the web implementation of the SAT principle enhanced learning, increased motivation and provided a transfer-able skill, without compromising accomplishment of major course goals.     

ICT in higher education: evaluating outcomes for health education

Abstract This paper presents an investigation that examined and compared the effectiveness of collaborative tutorial activities carried out in both web-based and face-to-face learning environments within an undergraduate health education subject. Effectiveness of the different learning environments was measured in terms of observed learning outcomes, analysis of learner interactions and reported perceptions of the learners regarding their experience. Results demonstrated that web-based environments, with embedded collaborative activities, can effectively foster rich learning experiences that result in attaining positive learning outcomes.     

Intervention and strategy analysis for web group-learning

Abstract Owing to the lack of face-to-face interactions, students using a web-based learning system are likely to study alone and with relatively little classmate support and pressure. Teachers in a web-based learning system may apply a group-learning model to overcome this problem. Teachers first need to organise, manage and monitor the group learning and they must take appropriate actions based on teaching strategies to improve the learning achievements of the students. To perform these tasks effectively, teachers must obtain relevant information by analysing the huge volume of web-access logs or by monitoring web interactions. This paper presents novel methodologies for developing instruments to assist teachers in performing intervention and strategy analysis. The proposed methodologies apply data mining tools provided by existing database management systems. Database techniques, including the multi-dimensional cube, are then applied to make student web logs meaningful and helpful to teachers in managing group learning. The associate rule mining tool is finally employed to assist teachers in analysing their pedagogical strategies. These tools relieve teachers of tedious data collection and analysis, allowing them to focus on managing the groups to promote students' learning achievement.     

A theoretical investigation of the emerging standards for web services

Currently, standards for web services are being developed via three different initiatives (W3C, Semantic web services and ebXML). To the best of our knowledge, no theoretical perspectives underlie these standardization efforts. Without the benefit of a strong theoretical basis, the results, within and across these initiatives, have remained piecemeal. We suggest ‘Language–Action Theories’ as a plausible perspective that can effectively define, assess and refine web services standards. In this paper, we first investigate the existing initiatives to identify commonalities that point to theories of ‘Language–Action’ as an appropriate theoretical basis for web services standards. Next, we adapt work from these theories to develop a comprehensive reference framework for understanding web services standards. Finally, we use this reference framework to assess the three initiatives, and analyze the findings to provide insights for future development and refinement of web services standards.

网页分类浏览器CBrowser的设计与实现

目前的浏览器只起着一种解释和显示网页的作用,难以适应各种各样的网络信息服务。从浏览器的自动化和智能化出发,设计并实现了一个具有网页自动分类功能的浏览器。     

Ontology-driven document enrichment: principles, tools and applications

In this paper, we present an approach to document enrichment, which consists of developing and integrating formal knowledge models with archives of documents, to provide intelligent knowledge retrieval and (possibly) additional knowledge-intensive services, beyond what is currently available using “standard” information retrieval and search facilities. Our approach is ontology-driven, in the sense that the construction of the knowledge model is carried out in a top-down fashion, by populating a given ontology, rather than in a bottom-up fashion, by annotating a particular document. In this paper, we give an overview of the approach and we examine the various types of issues (e.g. modelling, organizational and user interface issues) which need to be tackled to effectively deploy our approach in the workplace. In addition, we also discuss a number of technologies we have developed to support ontology-driven document enrichment and we illustrate our ideas in the domains of electronic news publishing, scholarly discourse and medical guidelines.