This paper discusses the provision of flexible querying facilities over heterogeneous data arising from lifelong learners' educational and work experiences. A key aim of such querying facilities is to allow learners to identify possible choices for their future learning and professional development by seeing what others have done. We motivate and…

Information retrieval (IR) systems have tremendously broaden users' access to information. However, users need to select their needs from trillions of information indexed daily. Due to the "semantic gap" between queries and indexed terms in IR system, whether users can satisfy their needs depends on whether they use the correct terms as…

This article examines how finding aids are structured and delivered, considering alternative approaches. It suggests that single-level displays, those that present a single component of a multilevel description to users at a time, have the potential to transform the delivery and display of collection information while improving the user…

In this paper, we propose a syntax-based text retrieval system for on-line language learning and use a fast regular expression search engine as its main component. Regular expression searches provide more scalable querying and search results than keyword-based searches. However, without a well-designed index scheme, the execution time of regular…

The web is a rich and diverse information source with incredible amounts of information about all kinds of subjects in various forms. This information source affords great opportunity to build systems that support users in their work and everyday lives. To help users explore information on the web, web search systems should find information that…

This study examines existent and new methods for evaluating the success of information retrieval systems. The theory underlying current methods is not robust enough to allow testing retrieval using different meta-tagging schema's. Traditional measures rely on judgments of whether a document is relevant to a particular question. A good system…

Academic libraries customize, support, and provide access to myriad information systems, each with complex graphical user interfaces. The number of possible information entry points on an academic library Web site is both daunting to the end-user and consistently challenging to library Web site designers. Faced with the challenges inherent in…

This article reports on our experiences in providing interoperability between the ARIADNE knowledge pool system (KPS) (Duval, Forte, Cardinaels, Verhoeven, Van Durm, Hendrickx et al., 2001) and several other heterogeneous learning object repositories and referatories.

Flexibility in query handling can be important if one types a search engine query that is misspelled, contains terms not in the database, or requires knowledge of a controlled vocabulary. Presents results of experiments that suggest the optimal form of similarity functions that are applicable to the task of phrase based retrieval to find either…

A task-oriented, comparative evaluation between four Web retrieval systems was performed; two using query-biased summarization, and two using the standard ranked titles/abstracts approach. Results indicate that query-biased summarization techniques appear to be more useful and effective in helping users gauge document relevance than the…

End user searching on the Web has become the primary method of locating images for many people. This study investigates the nature of Web image queries by attempting to map them to known image classification schemes. In this study, approximately 100,000 image queries from a major Web search engine were collected in 1997, 1999, and 2001. A…

Current search engines--even the constantly surprising Google--seem unable to leap the next big barrier in search: the trillions of bytes of dynamically generated data created by individual web sites around the world, or what some researchers call the "deep web." The challenge now is not information overload, but information overlook.…

Reports on a project that proposes and tests a comprehensive and systematic model of user evaluation of Web search engines. This article describes the model, including a set of criteria and measures and a method for implementation. A literature review portrays settings for developing the model and places applications of the model in contemporary…

Presents an application of a model of user evaluation of four major Web search engines (Alta Vista, Excite, Infoseek, and Lycos) by undergraduates. Evaluation was based on 16 performance measures representing five evaluation criteria-relevance, efficiency, utility, user satisfaction, and connectivity. Content analysis of verbal data identified a…

Describes the design and development of a case-based reasoning (CBR) knowledge repository, including its case library and the search engine to support the technology integration community. The process and results of ormative evaluation following the concept of participatory design are reported to set the context for further research and…