The design and evaluation of accessibility on web navigation

Web sites have been deployed to create and sustain business competitiveness in a trend of emerging Web technologies and growing e-commerce. One critical success factor of e-commerce is the ability to allow information to be retrieved from a Web site in an efficient and effective manner. Such ability, being determined by both the Web site structure and the Web page organization, can be measured in terms of accessibility and popularity of Web pages. The relationship between accessibility and popularity of web pages is dynamic in nature and can be analyzed to enhance a Web design. Having observed the lack of means to measure information retrieval of a Web site, this paper purports to introduce a guideline to evaluate Web page accessibility based on several structural-based accessibility models where an innovative accessibility–popularity (A–P) analysis is deployed to measure and, thereby, to modify a Web structure. Both push (i.e. demand driven) strategies and pull (i.e. design driven) strategies are incorporated into such guideline. Further, accessibility models are analyzed and compared in order to identify appropriate applications for each model. The paper is concluded by a summary of future directions of the accessibility models.     

Consistent Web site updating based on bidirectional transformation

A transformation-based Web site can keep the contents of a Web site consistent by furnishing a single database and a set of transformation programs, each generating a Web page from the database. However, when someone notices an error or stale content on a Web page in this style of Web site construction, the Web site maintainer must access a possibly huge database to update the corresponding content. In this paper, we propose a new approach to Web site construction based on bidirectional transformation, and report our design and implementation of a practical updating system called Vu-X. We bring the idea of bidirectional transformation to Web site construction, describing not only a forward transformation for generating Web pages from the database but also a backward transformation for reflecting modifications on the Web pages to the database. By use of the bidirectional transformation language Bi-X, we can obtain both transformations only by specifying a forward transformation. Our Vu-X system is implemented as a Web server built upon the Bi-X transformation engine, which can keep the content of Web sites consistent by updating Web pages in WYSIWYG style on Web browsers.     

Usability Testing of Academic Library Web Sites

ABSTRACT

This is a selective annotated bibliography of books, journal articles, and electronic resources relating to the usability assessment or testing of the academic library Web site. It focuses on the library Web site specifics, thus answering a librarian's need for one source of information on the available publications. All journal articles have been written by or for academic librarians. This bibliography embraces the issues of usability testing as a process, its goals, objectives, tools, and methodology. The bibliography is grouped by the following topics: background information, tools and methodologies, case studies, dedicated Web sites, and samples of presentations.     

A Review of “Reference Sources for Small and Medium-sized Libraries”

SUMMARY

In the summer of 1999, the libraries at the University of California, San Diego (UCSD) embarked on a Web redesign project. Essential to the new Web site were the development of a database of resources, Sage, and the creation of various in-house tools, which are used to enter and edit database resources. Tools were also created which assist in the creation and maintenance of various Web sites. With the completion of the project, UCSD students, faculty and staff can easily locate the resources and library information they need and library staff have more tools for Web site management.     

Towards adaptive Web sites: conceptual framework and case study

The creation of a complex Web site is a thorny problem in user interface design. In this paper we explore the notion of adaptive Web sites: sites that semi-automatically improve their organization and presentation by learning from visitor access patterns. It is easy to imagine and implement Web sites that offer shortcuts to popular pages. Are more sophisticated adaptive Web sites feasible? What degree of automation can we achieve?To address the questions above, we describe the design space of adaptive Web sites and consider a case study: the problem of synthesizing new index pages that facilitate navigation of a Web site. We present the PageGather algorithm, which automatically identifies candidate link sets to include in index pages based on user access logs. We demonstrate experimentally that PageGather outperforms the Apriori data mining algorithm on this task. In addition, we compare PageGather's link sets to pre-existing, human-authored index pages.     

An Examination of Library World Wide Web Sites at Medium-Sized Universities

ABSTRACT

This article presents the results of a study of World Wide Web (Web) Sites for 133 academic libraries serving medium-sized universities. Each library Web site was examined, and all of the features were recorded. The study identified 31 core components which were present in over 50 percent of the libraries surveyed. The study indicated that: the navigational and design aspects of library Web sites should be improved; materials should be placed on the sites only if they will be accessed and utilized by the user community; and libraries could profit by making greater use of online tutorials and virtual tours to supplement regular bibliographic instruction.     

A generalized expert system for database design

Generalized Expert System for Database Design (GESDD) is a compound expert system made up of two parts: (1) an expert system for generating methodologies for database design, called ESGM; and (2) an expert system for database design, called ESDD. ESGM provides a tool for the database design expert to specify different design methodologies or to modify existing ones. The database designer uses ESDD in conjunction with one of these methodologies to design a database starting from the requirement specification phase and producing a logical schema in one of the well-known data models, namely, the hierarchical data model, the network data model, or the relational data model. The system is evolutive in the sense that an existing methodology can be modified or a novel methodology can be added to the existing ones. GESDD is a menu-driven system and it is coded in Prolog     

Information system analysis and conceptual database design in production environments with M1

A methodology, called M¹, for information system analysis and database design of production environments is presented in detail. The originality of M¹ is to recognize the importance of integrating factory analysis methods for data and user requirements definition with logical database design methods for database specification. M¹ is a pragmatic, complete, manual methodology involving three major phases: Enterprise Modelling and Analysis which is the phase devoted to accurate analysis of the structure of the enterprise and precise definition of the scope of the future database application; Conceptual Design which is the phase concerned with data modelling of both static and dynamic properties of the enterprise; and Implementation Design which is the phase dealing with adaptation of the conceptual schema to the data model specifications of the physical database system used for application development and tuning performances of the physical system. The methodology is explained and illustrated by means of an example related to a Flexible Manufacturing System for mechanical parts.     

User satisfaction from commercial web sites: The effect of design and use

We empirically investigated the effect of user-based design and Web site usability on user satisfaction across four types of commercial Web sites: online shopping, customer self-service, trading, and publish/subscribe. To this end, a Web-based survey questionnaire was assembled, based on previously reported instruments for measuring user satisfaction, usability, and user-based design. Three hundred and fifty-nine respondents used the questionnaire to rate a collection of 20 popular commercial Web sites.Data collected were analyzed to test four hypotheses on the relationships among the attributes examined. The Web site attributes were also plotted on bi-dimensional perceptual maps in order to visualize their interactions. The two techniques yielded the same result, namely that trading sites are the lowest rated and that online shopping and customer self-service sites should serve as models for Web site developers. These findings are especially useful for designers of electronic commerce (EC) Web sites and can aid in the development and maintenance phases of Web site creation.     

Applying Learning Style Theory to Web Page Design

ABSTRACT

Library Web sites can be instructional tools, especially for those patrons who utilize library resources from their homes. Many libraries are developing online tutorials, but there is an opportunity for Web instruction on another level. The organization and design of a Web site can act as an instructional tool in itself. This paper is a call to library Web designers to assess their work in terms of learning style preferences. Learning style theory is based on how people process information and learn new material. Applying these ideas to Web page design can make library resources more accessible and improve the patron's comprehension of how the library works.     

Hypermedia presentation generation in Hera

Hera is a model-driven methodology for designing Semantic Web Information Systems (SWIS). Based on the principle of separation-of-concerns, Hera defines models to describe the different aspects of an SWIS. These models are represented using RDF, the foundation language of the Semantic Web. Hera is composed of two phases: the data collection phase, which integrates data from different sources, and the presentation generation phase, which builds a hypermedia presentation for the integrated data. The focus of this paper is on the hypermedia presentation generation phase and the associated model specifications. The Hera presentation generation phase has two variants: a static one that computes at once a full Web presentation, and a dynamic one that computes one-page-at-a-time by letting the user influence the next Web page to be presented. The dynamic variant proposes, in addition to the models from the static variant, new models to capture the data resulted from the user's interaction with the system. The implementation is based on a sequence of data transformations applied to the Hera models that eventually produces a hypermedia presentation.     

Authoring Personal Web Sites: A Description of Selected Tutorials and Beginner's Guides

ABSTRACT

People from all over the world are flocking to the Internet in record numbers. To meet the needs of this emerging population of World Wide Web users, this column identifies a select number of helpful Web sites dedicated to the creation of personal Web pages. Each site addresses the concepts of Hyper Text Markup Language (HTML) and Web page design. The needs of the novice Web page author are emphasized. The selected sites are relevant, accessible, and current.     

基于原子构件的友情链接设计

友情链接是Web应用程序中最基本的功能,在自己的网站上放置对方网站的LOGO图片或文字的网站名称,点击后切换或弹出另一个新的页面.本构件通过类代码实现,设计的基本思路是:将友情链接数据存储在数据库中,从数据库中读取数据绑定至Panel控件,也可向数据库添加友情链接数据,可以方便地在网站中设计友情链接.     

Databases deepen the Web

The Web has become the preferred medium for many database applications, such as e-commerce and digital libraries. These applications store information in huge databases that users access, query, and update through the Web. Database-driven Web sites have their own interfaces and access forms for creating HTML pages on the fly. Web database technologies define the way that these forms can connect to and retrieve data from database servers. The number of database-driven Web sites is increasing exponentially, and each site is creating pages dynamically-pages that are hard for traditional search engines to reach. Such search engines crawl and index static HTML pages; they do not send queries to Web databases. The information hidden inside Web databases is called the "deep Web" in contrast to the "surface Web" that traditional search engines access easily. We expect deep Web search engines and technologies to improve rapidly and to dramatically affect how the Web is used by providing easy access to many more information resources.     

A continuous analysis framework for the solution of location–allocation problems with dense demand

Location–allocation problems arise in several contexts, including supply chain and data mining. In its most common interpretation, the basic problem consists of optimally locating facilities and allocating customers to facilities so as to minimize the total cost. The standard approach to solving location–allocation problems is to model alternative location sites and customers as discrete entities. Many problem instances in practice involve dense demand data and uncertainties about the cost and locations of the potential sites. The use of discrete models is often inappropriate in such cases. This paper presents an alternative methodology where the market demand is modeled as a continuous density function and the resulting formulation is solved by means of calculus techniques. The methodology prioritizes the allocation decisions rather than location decisions, which is the common practice in the location literature. The solution algorithm proposed in this framework is a local search heuristic (steepest-descent algorithm) and is applicable to problems where the allocation decisions are in the form of polygons, e.g., with Euclidean distances. Extensive computational experiments confirm the efficiency of the proposed methodology.     

A Distribution Design Methodology for Object DBMS

The design of distributed databases involves making decisions on the fragmentation and placement of data and programs across the sites of a computer network. The first phase of the distribution design in a top-down approach is the fragmentation phase, which clusters in fragments the information accessed simultaneously by applications. Most distribution design algorithms propose a horizontal or vertical class fragmentation. However, the user has no assistance in the choice between these techniques. In this work we present a detailed methodology for the design of distributed object databases that includes: (i) an analysis phase, to indicate the most adequate fragmentation technique to be applied in each class of the database schema; (ii) a horizontal class fragmentation algorithm, and (iii) a vertical class fragmentation algorithm. Basically, the analysis phase is responsible for driving the choice between the horizontal and the vertical partitioning techniques, or even the combination of both, in order to assist distribution designers in the fragmentation phase of object databases. Experiments using our methodology have resulted in fragmentation schemas offering a high degree of parallelism together with an important reduction of irrelevant data.     

本体论研究综述

起源于哲学的本体论(ontology)在信息科学领域受到广泛关注,其重要性已在许多方面表现出来,如知识工程、数据库设计和集成、信息检索与获取、软件工程、自然语言处理等．尤其是本体论在Web上的应用导致了语义Web的诞生,有望解决Web信息共享时的语义问题,实现世界范围的知识级信息集成．综述计算机科学中本体论的研究和应用现状,主要内容包括：本体论的起源和发展,本体论的定义,本体论的描述语言以及构建方法论,本体论与语义Web,以及本体论的应用等．