Search (116 results, page 2 of 6)

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Date

22. 6.2002 19:41:31

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Abstract

Based on a decade's experience with the Alexandria Digital Library Project, seven issues are presented that arise in creating georeferenced digital libraries, and that appear to be intrinsic to the problem of creating any library-like information system that operates on georeferenced and geospatial resources. The first and foremost issue is providing discovery of georeferenced resources. Related to discovery are the issues of gazetteer integration and specialized ranking of search results. Strong data typing and scalability are implementation issues. Providing spatial context is a critical user interface issue. Finally, sophisticated resource access mechanisms are necessary to operate on geospatial resources.

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Abstract

Reference services have taken a central place in library and information services. They are also regarded as personalised services since in most cases a personal discussion takes place between a user and a reference librarian. Based on this, the librarian points to the sources that are considered to be most appropriate to meet the specific information need(s) of the user. Since the Web and digital libraries are meant for providing direct access to information sources and services without the intervention of human intermediaries, the pertinent question that appears is whether we need reference services in digital libraries, and, if so, how best to offer such services. Current digital libraries focus more on access to, and retrieval of, digital information, and hardly lay emphasis on the service aspects. This may have been caused by the narrower definitions of digital libraries formulated by digital library researchers. This paper looks at the current state of research in personalised information services in digital libraries. It first analyses some representative definitions of digital libraries in order to establish the need for personalised services. It then provides a brief overview of the various online reference and information services currently available on the Web. The paper also briefly reviews digital library research that specifically focuses on the personalisation of digital libraries and the provision of digital reference and information services. Finally, the paper proposes some new areas of research that may be undertaken to improve the provision of personalised information services in digital libraries.

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Abstract

Flexible organization of information is one of the key design challenges in any digital library. For the past year, we have been working with members of the National Digital Library Project (NDLP) at the Library of Congress to build an experimental system to organize and store library collections. This is a report on the work. In particular, we describe how a few technical building blocks are used to organize the material in collections, such as the NDLP's, and how these methods fit into a general distributed computing framework. The technical building blocks are part of a framework that evolved as part of the Computer Science Technical Reports Project (CSTR). This framework is described in the paper, "A Framework for Distributed Digital Object Services", by Robert Kahn and Robert Wilensky (1995). The main building blocks are: "digital objects", which are used to manage digital material in a networked environment; "handles", which identify digital objects and other network resources; and "repositories", in which digital objects are stored. These concepts are amplified in "Key Concepts in the Architecture of the Digital Library", by William Y. Arms (1995). In summer 1995, after earlier experimental development, work began on the implementation of a full digital library system based on this framework. In addition to Kahn/Wilensky and Arms, several working papers further elaborate on the design concepts. A paper by Carl Lagoze and David Ely, "Implementation Issues in an Open Architectural Framework for Digital Object Services", delves into some of the repository concepts. The initial repository implementation was based on a paper by Carl Lagoze, Robert McGrath, Ed Overly and Nancy Yeager, "A Design for Inter-Operable Secure Object Stores (ISOS)". Work on the handle system, which began in 1992, is described in a series of papers that can be found on the Handle Home Page. The National Digital Library Program (NDLP) at the Library of Congress is a large scale project to convert historic collections to digital form and make them widely available over the Internet. The program is described in two articles by Caroline R. Arms, "Historical Collections for the National Digital Library". The NDLP itself draws on experience gained through the earlier American Memory Program. Based on this work, we have built a pilot system that demonstrates how digital objects can be used to organize complex materials, such as those found in the NDLP. The pilot was demonstrated to members of the library in July 1996. The pilot system includes the handle system for identifying digital objects, a pilot repository to store them, and two user interfaces: one designed for librarians to manage digital objects in the repository, the other for library patrons to access the materials stored in the repository. Materials from the NDLP's Coolidge Consumerism compilation have been deposited into the pilot repository. They include a variety of photographs and texts, converted to digital form. The pilot demonstrates the use of handles for identifying such material, the use of meta-objects for managing sets of digital objects, and the choice of metadata. We are now implementing an enhanced prototype system for completion in early 1997.

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Abstract

Since the 1960s, librarians have projected a vision of a digital library that offers seamless access to a vast world of scholarly information of all types. Until the 1990s, however, digital technologies lacked the power and capacity to deliver on the vision. During the 1990s, technology platforms, networking technologies, electronic resources, and the evolution of standards matured sufficiently to lay the foundation for the vision to be fulfilled. As this maturation was taking place, the rapid growth of electronic resources was based on numerous proprietary systems making access across such systems impossible. The scholars portal project is an effort to create a search and retrieval tool that will provide an interim solution to this problem until such time as those systems are built on a unified set of standards and data formats.

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Abstract

The initial research on semantic digital libraries resulted in the design and implementation of JeromeDL; current research on online social networking and information discovery delivered new sets of features that were implemented in JeromeDL. Eventually, this digital library has been redesigned to follow the architecture of a social semantic digital library. JeromeDL describes each resource using three types of metadata: structure, bibliographic and community. It delivers services leveraging each of these information types. Annotations based on the structure and legacy metadata, and bibliographic ontology are rendered to the users in one, mixed, representation of library resources. Community annotations are managed by separate services, such as social semantic collaborative filtering or blogging component

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Date

22. 6.2002 19:38:24

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Date

22. 6.2002 19:41:16

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Abstract

Purpose - This study aims to investigate the effects of different search and browse features in digital libraries (DLs) on task interactions, and what features would lead to poor user experience. Design/methodology/approach - Three operational DLs: ACM, IEEE CS, and IEEE Xplore are used in this study. These three DLs present different features in their search and browsing designs. Two information-seeking tasks are constructed: one search task and one browsing task. An experiment was conducted in a usability laboratory. Data from 35 participants are collected on a set of measures for user interactions. Findings - The results demonstrate significant differences in many aspects of the user interactions between the three DLs. For both search and browse designs, the features that lead to poor user interactions are identified. Research limitations/implications - User interactions are affected by specific design features in DLs. Some of the design features may lead to poor user performance and should be improved. The study was limited mainly in the variety and the number of tasks used. Originality/value - The study provided empirical evidence to the effects of interaction design features in DLs on user interactions and performance. The results contribute to our knowledge about DL designs in general and about the three operational DLs in particular.

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Abstract

Purpose - The general science portal "vascoda" merges structured, high-quality information collections from more than 40 providers on the basis of search engine technology (FAST) and a concept which treats semantic heterogeneity between different controlled vocabularies. First experiences with the portal show some weaknesses of this approach which come out in most metadata-driven Digital Libraries (DLs) or subject specific portals. The purpose of the paper is to propose models to reduce the semantic complexity in heterogeneous DLs. The aim is to introduce value-added services (treatment of term vagueness and document re-ranking) that gain a certain quality in DLs if they are combined with heterogeneity components established in the project "Competence Center Modeling and Treatment of Semantic Heterogeneity". Design/methodology/approach - Two methods, which are derived from scientometrics and network analysis, will be implemented with the objective to re-rank result sets by the following structural properties: the ranking of the results by core journals (so-called Bradfordizing) and ranking by centrality of authors in co-authorship networks. Findings - The methods, which will be implemented, focus on the query and on the result side of a search and are designed to positively influence each other. Conceptually, they will improve the search quality and guarantee that the most relevant documents in result sets will be ranked higher. Originality/value - The central impact of the paper focuses on the integration of three structural value-adding methods, which aim at reducing the semantic complexity represented in distributed DLs at several stages in the information retrieval process: query construction, search and ranking and re-ranking.

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Abstract

Nowadays, end-users have quick and direct access to massive amount of information available on the Net. However, this information is unorganized expecting users to be able to identify and evaluate it in accordance with their information needs. Subject based information Gateways SBIG, organized collections of networked information, provide users with a catalogue of authoritative Internet resources, which can be searched and/ or browsed. This paper provides an evaluation of one such gateway - the Art, Design, Architecture & Media Gateway ADAM. It provides information on who these users are, how often they use the service, what their reasons for use are, which search methods and services they prefer and what are the advantages and disadvantages of an online information service.

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Abstract

To meet a perceived need for information professionals engaging in projects on document and knowledge management, a new course on enterprise information portals (EIP) and intranets has been established at the Royal School of Library and Information Science (RSLIS). The aim of the course has been to provide the graduates with a better understanding of fundamental theoretical, methodological and practical aspects of developing and implementing an EIP. This paper addresses the theoretical, methodological and pedagogical aspects of developing the course and how or whether the expected learning outcome has been reached.

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Abstract

There has been a recent explosion of interest in digital music libraries. In particular, interactive melody retrieval is a striking example of a search paradigm that differs radically from the standard full-text search. Many different techniques have been proposed for melody matching, but the area lacks standard databases that allow them to be compared on common grounds--and copyright issues have stymied attempts to develop such a corpus. This paper focuses on methods for evaluating different symbolic music matching strategies, and describes a series of experiments that compare and contrast results obtained using three dominant paradigms. Combining two of these paradigms yields a hybrid approach which is shown to have the best overall combination of efficiency and effectiveness.

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Abstract

European digital libraries have existed in diverse forms and with quite different functions, priorities, and aims. However, there are some common features of European-based initiatives that are relevant to non-European communities. There are now many more challenges and changes than ever before, and the development rate of new digital libraries is ever accelerating. Delivering educational, cultural, and research resources-especially from major scientific and cultural organizations-has become a core mission of these organizations. Using these resources they will be able to investigate, educate, and elucidate, in order to promote and disseminate and to preserve civilization. Extremely important in conceptualizing the digital environment priorities in Europe was its cultural heritage and the feeling that these rich resources should be open to Europe and the global community. In this book we focus on European digitized heritage and digital culture, and its potential in the digital age. We specifically look at the EU and its approaches to digitization and digital culture, problems detected, and achievements reached, all with an emphasis on digital cultural heritage. We seek to report on important documents that were prepared on digitization; copyright and related documents; research and education in the digital libraries field under the auspices of the EU; some other European and national initiatives; and funded projects. The aim of this book is to discuss the development of digital libraries in the European context by presenting, primarily to non-European communities interested in digital libraries, the phenomena, initiatives, and developments that dominated in Europe. We describe the main projects and their outcomes, and shine a light on the number of challenges that have been inspiring new approaches, cooperative efforts, and the use of research methodology at different stages of the digital libraries development. The specific goals are reflected in the structure of the book, which can be conceived as a guide to several main topics and sub-topics. However, the author?s scope is far from being comprehensive, since the field of digital libraries is very complex and digital libraries for cultural heritage is even moreso.

Series

Synthesis lectures on information concepts, retrieval, and services ; 58

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Date

22. 6.2002 19:42:22

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Date

22. 6.2002 19:41:00

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Source

Library hi tech. 22(2004) no.3, S.295-306

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Source

Wissensspeicher in digitalen Räumen: Nachhaltigkeit - Verfügbarkeit - semantische Interoperabilität. Proceedings der 11. Tagung der Deutschen Sektion der Internationalen Gesellschaft für Wissensorganisation, Konstanz, 20. bis 22. Februar 2008. Hrsg.: J. Sieglerschmidt u. H.P.Ohly