Integrating database and World Wide Web technologies

Integrating database and World Wide Web technologies is another topic where industrial and practical activities lead ahead of academic ones. The purpose of this article is to survey the related activities from database people's view and stimulate the interests among the database community. It covers three aspects. First, the efforts that apply established database techniques to retrieving Web information are summarized. These efforts aim to overcome the inadequacy of file system technology on which the Web is based, so that information can be retrieved easily and quickly from the Web. Second, various approaches to interfacing databases via the Web are discussed, with examples of accomplished prototypes and commercial products showing recent advances. Finally, some possible extensions to the traditional database techniques are investigated for building fully fledged Webbased database applications.     

Mobile agents for World Wide Web distributed database access

The popularity of the Web as a universal access mechanism for network information has created the need for developing Web-based DBMS client/server applications. However, the current commercial applet-based approaches for accessing database systems offer limited flexibility, scalability, and robustness. We propose a new framework for Web-based distributed access to database systems based on Java-based mobile agents. The framework supports lightweight, portable, and autonomous clients as well as operation on slow or expensive networks. The implementation of the framework using the aglet workbench shows that its performance is comparable to, and in some case outperforms, the current approach. In fact, in wireless and dial-up environments and for average size transactions, a client/agent/server adaptation of the framework provides a performance improvement of approximately a factor of ten. For the fixed network, the gains are about 40 percent and 30 percent, respectively. We expect our framework to perform even better when deployed using different implementation platforms as indicated by our preliminary results from an implementation based on Voyager     

The World Wide Web

Abstract

The World Wide Web is increasingly being used by libraries as a way to extend traditional services to patrons. The Web can also be used as a tool to facilitate communications between library professionals and to deliver presentations, organize exhibits, and develop demonstration projects. The allocation of personal Web work space on a library server provides librarians with a means to experiment with using the medium and a place to publish information of interest to the library profession. This paper explores the uses of the Web to enhance communications between library professionals and addresses some of the issues associated with such uses.     

InfoMonitor: unobtrusively archiving a World Wide Web server

It is important to provide long-term preservation of digital data even when those data are stored in an unreliable system such as a filesystem, a legacy database, or even the World Wide Web. In this paper we focus on the problem of archiving the contents of a Web site without disrupting users who maintain the site. We propose an archival storage system, the InfoMonitor, in which a reliable archive is integrated with an unmodified existing store. Implementing such a system presents various challenges related to the mismatch of features between the components such as differences in naming and data manipulation operations. We examine each of these issues as well as solutions for the conflicts that arise. We also discuss our experience using the InfoMonitor to archive the Stanford Database Groups Web site.     

World Wide Web概述

随着网络化时代的到来,人们越来越关注Ｉｎｔｅｒｎｅｔ上的各种功能,为此本文对基于Ｉｎｙｔｅｒｎｅｔ的ＷＷＷ网的组织,浏览器,地址编排和工作原理作了简要的概述。     

On the World Wide Web

ABSTRACT

An analysis of Web citations was performed to examine three aspects of scholarly and research communication: use of authoritative information, use of correct citation style, and availability of the cited sources for the purpose of verification. Results of the study indicate that a database or a repository of Web citations needs to be established.     

ANATAGONOMY: a personalized newspaper on the World Wide Web

This paper describes a personalized newspaper on the World Wide Web (WWW), called ANATAGONOMY. The main feature of this system is that the newspaper is personalized without asking the users to specify their preferences explicitly. The system monitors user operations on the articles and reflects them in the user profiles. Differently from conventional newspapers on the WWW, our system sends an interaction agent implemented as a Java applet to the client side, and the agent monitors the user operations and creates each user's newspaper pages automatically. The server side manages user profiles and anticipates how interesting an article would be for each user. The interaction agent on the client side manages all the user interactions, including the automatic layout of pages. Our system has page multiple layout algorithms and the user can switch from one view to another anytime, according to the preference or machine environment. On one of the views, the user can even see all the articles sequentially without performing any operations. We evaluated a scheme in which the user scores each article explicitly, and a scheme in which all the personalization is done automatically. The results show that automatic personalization works well when some parameters are set properly.     

Caching on the World Wide Web

With the recent explosion in usage of the World Wide Web, the problem of caching Web objects has gained considerable importance. Caching on the Web differs from traditional caching in several ways. The nonhomogeneity of the object sizes is probably the most important such difference. In this paper, we give an overview of caching policies designed specifically for Web objects and provide a new algorithm of our own. This new algorithm can be regarded as a generalization of the standard LRU algorithm. We examine the performance of this and other Web caching algorithms via event- and trace-driven simulation     

WWW上的缓存技术

WWW上的缓存技术被认为是改进Web性能的有效技术之一,总观了缓存系统所要解决的问题,针对需要解决的问题,总结了目前为止所提出的各种缓存策略,最后概括了理想的WWW缓存系统应该具备的性能指标。     

Mosaic and the World Wide Web

The World-Wide Web, an information service on the Internet, uses hypertext links to other textual documents or files. Users can click on a highlighted word or words in the text to provide additional information about the selected word(s). Users can also access graphic pictures, images, audio clips, or even full-motion video through hypermedia, an extension of hypertext. One of the most popular graphics-oriented browsers is Mosaic, which was developed at the National Center for Supercomputing Applications (NCSA) as a way to graphically-navigate the WWW. Mosaic browsers are currently available for Unix workstations running X Windows, PCs running Microsoft Windows, and Macintosh computers. Mosaic can access data in WWW servers, Wide Area Information Servers (WAIS), Gopher servers, Archie servers, and several others. The World-Wide Web is still evolving at a rapid pace. Distributed hypermedia systems on the Internet will continue to be an active area of development in the future. The flexibility of the WWW design, its use of hyperlinks, and the integration of existing WAIS and Gopher information resources, make the WWW ideal for future research and study. Highly interactive multimedia applications will require more sophisticated tools than currently exist. The most significant issue that needs to be resolved is the mismatch between WWW system capabilities and user requirements in the areas of presentation and quality of service     

Laying the foundations for a World Wide Argument Web

This paper lays theoretical and software foundations for a World Wide Argument Web (WWAW): a large-scale Web of inter-connected arguments posted by individuals to express their opinions in a structured manner. First, we extend the recently proposed Argument Interchange Format (AIF) to express arguments with a structure based on Walton's theory of argumentation schemes. Then, we describe an implementation of this ontology using the RDF Schema Semantic Web-based ontology language, and demonstrate how our ontology enables the representation of networks of arguments on the Semantic Web. Finally, we present a pilot Semantic Web-based system, ArgDF, through which users can create arguments using different argumentation schemes and can query arguments using a Semantic Web query language. Manipulation of existing arguments is also handled in ArgDF: users can attack or support parts of existing arguments, or use existing parts of an argument in the creation of new arguments. ArgDF also enables users to create new argumentation schemes. As such, ArgDF is an open platform not only for representing arguments, but also for building interlinked and dynamic argument networks on the Semantic Web. This initial public-domain tool is intended to seed a variety of future applications for authoring, linking, navigating, searching, and evaluating arguments on the Web.     

Enhancing a Newspaper Collection Using the World Wide Web

Abstract

Serial cancellations have reduced the print newspaper collection at the University of Toledo (UT) Library by about one third since 1990. In the meantime, the number of newspapers publishing on the World Wide Web has skyrocketed, prompting UT to investigate accessing newspapers online. The immediate goal of this project is to provide library users with access to online versions of cancelled print newspapers, and eventually to enhance the collection even further with additional electronic newspapers. This article examines the trends in online newspaper publishing, researches the availability of Web sites in relation to the UT newspaper collection, critically reviews the sites found, and discusses the issues surrounding access to an online collection.     

NCSA's World Wide Web server: design and performance

To support continued growth, WWW servers must manage a multigigabyte (in some instances a multiterabyte) database of multimedia information while concurrently serving multiple request streams. This places demands on the servers' underlying operating systems and file systems that lie far outside today's normal operating regime. Simply put, WWW servers must become more adaptive and intelligent. The first step on this path is understanding extant access patterns and responses. The article examines extant Web access patterns with the aim of developing more efficient file-caching and prefetching strategies     

AMORE: A World Wide Web image retrieval engine

Search engines are useful because they allow the user to find information of interest from the World Wide Web. However, most of the popular search engines today are textual; they do not allow the user to find images from the Web. This paper describes AMORE, a Web search engine that allows the user to retrieve images from the Web by specifying relevant keywords or a similar image. Text and image search can also be combined. Moreover, we have developed a Query Result Visualization Environment that allows the organization of the results if many images are retrieved. In this paper we present AMORE's user interface and explain the technique for retrieving images visually similar to a user specified image. The method of automatically assigning relevant keywords to the images is then explained. Finally, the architecture of the system as well as some interesting observations of our experiences with AMORE are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

基于WWW的音频信息系统

介绍了网络多媒体信息的特点,ＷＷＷ和Ｊａｖａ的音频功能,并描述了音频信息的结构和客户访问音频信息的软件界面。     

Adaptive leases: a strong consistency mechanism for the World Wide Web

We argue that weak cache consistency mechanisms supported by existing Web proxy caches must be augmented by strong consistency mechanisms to support the growing diversity in application requirements. Existing strong consistency mechanisms are not appealing for Web environments due to their large state space or control message overhead. We focus on the lease approach that balances these trade-offs and present analytical models and policies for determining the optimal lease duration. We present extensions to the HTTP protocol to incorporate leases and then implement our techniques in the Squid proxy cache and the Apache Web server. Our experimental evaluation of the leases approach shows that: 1) our techniques impose modest overheads even for long leases (a lease duration of 1 hour requires state to be maintained for 1030 leases and imposes an per-object overhead of a control message every 33 minutes), 2) leases yields a 138-425 percent improvement over existing strong consistency mechanisms, and 3) the implementation overhead of leases is comparable to existing weak consistency mechanisms.     

BASAR: a framework for integrating agents in the World Wide Web

At GMD's Human Computer Interaction Research Division, we are working on a system called BASAR (Building Agents Supporting Adaptive Retrieval). BASAR, a Smalltalk-based program that runs on Unix platforms, involves intelligent agents that actively support construction and management of a user's personal information space. Possible agent tasks include supporting navigation and browsing; simplifying information retrieval; sorting, organizing, and indexing user-jobs; and filtering information from large databases. BASAR's interface is based on the concept of indirect management. That is, computer agents support human users in a cooperative process where both agents and users can initiate communication, monitor events, and perform tasks