Search (19 results, page 1 of 1)

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Abstract

This article describes an approach for linking geographically distributed collections of metadata so that they are searchable as a single collection. We describe the infrastructure, which uses standard Internet protocols such as the Lightweight Directory Access Protocol (LDAP) and the Common Indexing Protocol (CIP), to distribute queries, return results, and exchange index information. We discuss the advantages of using linked collections of authoritative metadata as an alternative to using a keyword indexing search-engine for resource discovery. We examine other architectures that use metadata for resource discovery, such as Dienst/NCSTRL, the AHDS HTTP/Z39.50 Gateway, and the ROADS initiative. Finally, we discuss research issues and future directions of the project. The Internet Scout Project, which is funded by the National Science Foundation and is located in the Computer Sciences Department at the University of Wisconsin-Madison, is charged with assisting the higher education community in resource discovery on the Internet. To that end, the Scout Report and subsequent subject-specific Scout Reports were developed to guide the U.S. higher education community to research-quality resources. The Scout Report Signpost utilizes the content from the Scout Reports as the basis of a metadata collection. Signpost consists of more than 2000 cataloged Internet sites using established standards such as Library of Congress subject headings and abbreviated call letters, and emerging standards such as the Dublin Core (DC). This searchable and browseable collection is free and freely accessible, as are all of the Internet Scout Project's services.
As well developed as both the Scout Reports and Signpost are, they cannot capture the wealth of high-quality content that is available on the Internet. An obvious next step toward increasing the usefulness of our own collection and its value to our customer base is to partner with other high-quality content providers who have developed similar collections and to develop a single, virtual collection. Project Isaac (working title) is the Internet Scout Project's latest resource discovery effort. Project Isaac involves the development of a research testbed that allows experimentation with protocols and algorithms for creating, maintaining, indexing and searching distributed collections of metadata. Project Isaac's infrastructure uses standard Internet protocols, such as the Lightweight Directory Access Protocol (LDAP) and the Common Indexing Protocol (CIP) to distribute queries, return results, and exchange index or centroid information. The overall goal is to support a single-search interface to geographically distributed and independently maintained metadata collections.

Theme

Verteilte bibliographische Datenbanken

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Theme

Internet

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Abstract

Es scheint naheliegend, daß der Unsicherheit, welche durch die "Vielfalt der möglichen sprachlichen Ausdrucksweisen für einen Sachverhalt" beim Beschlagworter ausgelöst wird, dadurch begegnet werden soll, "daß immer nur eine der möglichen Formen gewählt wird". Der Ruf nach einer "Standardisie- rung der Schlagwörter" geht damit Hand in Hand. Zwei Ergebnisse dieser Standardisierungsbemühungen werden im folgenden dargestellt; ein Punkt aber sollte dabei nicht übersehen werden: "Ein allgemein akzeptiertes Verfahren der Inhaltsanalyse gibt es bisher nicht und es ist offen, ob das Problem überhaupt gelöst werden kann." Standardisiert kann demnach nur das Schlagwortsystem werden, nicht aber seine konkrete Anwendung bei der inhaltlichen Erschließung von Dokumenten.

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Source

Ariadne. 1999, no.22

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Abstract

In this era of the Internet and distributed, multimedia computing, new and emerging classes of information systems applications have swept into the lives of office workers and people in general. From digital libraries, multimedia systems, geographic information systems, and collaborative computing to electronic commerce, virtual reality, and electronic video arts and games, these applications have created tremendous opportunities for information and computer science researchers and practitioners. As applications become more pervasive, pressing, and diverse, several well-known information retrieval (IR) problems have become even more urgent. Information overload, a result of the ease of information creation and transmission via the Internet and WWW, has become more troublesome (e.g., even stockbrokers and elementary school students, heavily exposed to various WWW search engines, are versed in such IR terminology as recall and precision). Significant variations in database formats and structures, the richness of information media (text, audio, and video), and an abundance of multilingual information content also have created severe information interoperability problems -- structural interoperability, media interoperability, and multilingual interoperability.

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Abstract

The purpose of this essay is to identify and explore the dynamics of the literature associated with the Dublin Core Workshop Series. The essay opens by identifying the problems that the Dublin Core Workshop Series is addressing, the status of the Internet at the time of the first workshop, and the contributions each workshop has made to the ongoing discussion. The body of the essay describes the characteristics of the literature, highlights key documents, and identifies the major researchers. The essay closes with evaluation of the literary trends and considerations of future research directions. The essay concludes that a shift from a descriptive emphasis to a more empirical form of literature is about to take place. Future research questions are identified in the areas of satisfying searcher needs, the impact of surrogate descriptions on search engine performance, and the effectiveness of surrogate descriptions in authenticating Internet resources.

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Abstract

Do a search on AltaVista for "algebra". What do you get? Nearly 700,000 hits, of which AltaVista will allow you to view only what it determines is the top 200. Major search engines such as AltaVista, Excite, HotBot, Lycos, and the like continue to provide a valuable service, but with the recent growth of the Internet, topic-specific sites that provide some organization to the topic are increasingly important. It the goal of the Mathematics Archives to make it easier for the ordinary user to find useful mathematical information on the Web. The Mathematics Archives (http://archives.math.utk.edu) is a multipurpose site for mathematics on the Internet. The focus is on materials which can be used in mathematics education (primarily at the undergraduate level). Resources available range from shareware and public domain software to electronic proceedings of various conferences, to an extensive collection of annotated links to other mathematical sites. All materials on the Archives are categorized and cross referenced for the convenience of the user. Several search mechanisms are provided. The Harvest search engine is implemented to provide a full text search of most of the pages on the Archives. The software we house and our list of annotated links to mathematical sites are both categorized by subject matter. Each of these collections has a specialized search engine to assist the user in locating desired material. Services at the Mathematics Archives are divided up into five broad topics: * Links organized by Mathematical Topics * Software * Teaching Materials * Other Math Archives Features * Other Links

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Theme

Internet

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Abstract

The Internet would not be very useful if communication were limited to textual exchanges between speakers of English located in the United States. Rather, its value lies in its ability to enable people from multiple nations, speaking multiple languages, to employ multiple media in interacting with each other. While computer networks broke through national boundaries long ago, they remain much more effective for textual communication than for exchanges of sound, images, or mixed media -- and more effective for communication in English than for exchanges in most other languages, much less interactions involving multiple languages. Supporting searching and display in multiple languages is an increasingly important issue for all digital libraries accessible on the Internet. Even if a digital library contains materials in only one language, the content needs to be searchable and displayable on computers in countries speaking other languages. We need to exchange data between digital libraries, whether in a single language or in multiple languages. Data exchanges may be large batch updates or interactive hyperlinks. In any of these cases, character sets must be represented in a consistent manner if exchanges are to succeed. Issues of interoperability, portability, and data exchange related to multi-lingual character sets have received surprisingly little attention in the digital library community or in discussions of standards for information infrastructure, except in Europe. The landmark collection of papers on Standards Policy for Information Infrastructure, for example, contains no discussion of multi-lingual issues except for a passing reference to the Unicode standard. The goal of this short essay is to draw attention to the multi-lingual issues involved in designing digital libraries accessible on the Internet. Many of the multi-lingual design issues parallel those of multi-media digital libraries, a topic more familiar to most readers of D-Lib Magazine. This essay draws examples from multi-media DLs to illustrate some of the urgent design challenges in creating a globally distributed network serving people who speak many languages other than English. First we introduce some general issues of medium, culture, and language, then discuss the design challenges in the transition from local to global systems, lastly addressing technical matters. The technical issues involve the choice of character sets to represent languages, similar to the choices made in representing images or sound. However, the scale of the language problem is far greater. Standards for multi-media representation are being adopted fairly rapidly, in parallel with the availability of multi-media content in electronic form. By contrast, we have hundreds (and sometimes thousands) of years worth of textual materials in hundreds of languages, created long before data encoding standards existed. Textual content from past and present is being encoded in language and application-specific representations that are difficult to exchange without losing data -- if they exchange at all. We illustrate the multi-language DL challenge with examples drawn from the research library community, which typically handles collections of materials in 400 or so languages. These are problems faced not only by developers of digital libraries, but by those who develop and manage any communication technology that crosses national or linguistic boundaries.

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Abstract

Information retrieval over the Internet increasingly requires the filtering of thousands of heterogeneous information sources. Important sources of information include not only traditional databases with structured data and queries, but also increasing numbers of non-traditional, semi- or unstructured collections such as Web sites, FTP archives, etc. As the number and variability of sources increases, new ways of automatically summarizing, discovering, and selecting collections relevant to a user's query are needed. One such method involves the use of classification schemes, such as the Library of Congress Classification (LCC) [10], within which a collection may be represented based on its content, irrespective of the structure of the actual data or documents. For such a system to be useful in a large-scale distributed environment, it must be easy to use for both collection managers and users. As a result, it must be possible to classify documents automatically within a classification scheme. Furthermore, there must be a straightforward and intuitive interface with which the user may use the scheme to assist in information retrieval (IR).

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Theme

Internet

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Date

22. 1.2016 17:30:31

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Date

22. 1.2016 17:30:31

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Theme

Internet

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Theme

Internet

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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

The explosive growth of the Internet and other sources of networked information have made automatic mediation of access to networked information sources an increasingly important problem. Much of this information is expressed as electronic text, and it is becoming practical to automatically convert some printed documents and recorded speech to electronic text as well. Thus, automated systems capable of detecting useful documents are finding widespread application. With even a small number of languages it can be inconvenient to issue the same query repeatedly in every language, so users who are able to read more than one language will likely prefer a multilingual text retrieval system over a collection of monolingual systems. And since reading ability in a language does not always imply fluent writing ability in that language, such users will likely find cross-language text retrieval particularly useful for languages in which they are less confident of their ability to express their information needs effectively. The use of such systems can be also be beneficial if the user is able to read only a single language. For example, when only a small portion of the document collection will ever be examined by the user, performing retrieval before translation can be significantly more economical than performing translation before retrieval. So when the application is sufficiently important to justify the time and effort required for translation, those costs can be minimized if an effective cross-language text retrieval system is available. Even when translation is not available, there are circumstances in which cross-language text retrieval could be useful to a monolingual user. For example, a researcher might find a paper published in an unfamiliar language useful if that paper contains references to works by the same author that are in the researcher's native language.

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Abstract

Information retrieval over the Internet increasingly requires the filtering of thousands of heterogeneous information sources. Important sources of information include not only traditional databases with structured data and queries, but also increasing numbers of non-traditional, semi- or unstructured collections such as Web sites, FTP archives, etc. As the number and variability of sources increases, new ways of automatically summarizing, discovering, and selecting collections relevant to a user's query are needed. One such method involves the use of classification schemes, such as the Library of Congress Classification (LCC), within which a collection may be represented based on its content, irrespective of the structure of the actual data or documents. For such a system to be useful in a large-scale distributed environment, it must be easy to use for both collection managers and users. As a result, it must be possible to classify documents automatically within a classification scheme. Furthermore, there must be a straightforward and intuitive interface with which the user may use the scheme to assist in information retrieval (IR). Our work with the Alexandria Digital Library (ADL) Project focuses on geo-referenced information, whether text, maps, aerial photographs, or satellite images. As a result, we have emphasized techniques which work with both text and non-text, such as combined textual and graphical queries, multi-dimensional indexing, and IR methods which are not solely dependent on words or phrases. Part of this work involves locating relevant online sources of information. In particular, we have designed and are currently testing aspects of an architecture, Pharos, which we believe will scale up to 1.000.000 heterogeneous sources. Pharos accommodates heterogeneity in content and format, both among multiple sources as well as within a single source. That is, we consider sources to include Web sites, FTP archives, newsgroups, and full digital libraries; all of these systems can include a wide variety of content and multimedia data formats. Pharos is based on the use of hierarchical classification schemes. These include not only well-known 'subject' (or 'concept') based schemes such as the Dewey Decimal System and the LCC, but also, for example, geographic classifications, which might be constructed as layers of smaller and smaller hierarchical longitude/latitude boxes. Pharos is designed to work with sophisticated queries which utilize subjects, geographical locations, temporal specifications, and other types of information domains. The Pharos architecture requires that hierarchically structured collection metadata be extracted so that it can be partitioned in such a way as to greatly enhance scalability. Automated classification is important to Pharos because it allows information sources to extract the requisite collection metadata automatically that must be distributed.

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Abstract

The Z39.50 standard for information retrieval is important from a number of perspectives. While still not widely known within the computer networking community, it is a mature standard that represents the culmination of two decades of thinking and debate about how information retrieval functions can be modeled, standardized, and implemented in a distributed systems environment. And - importantly -- it has been tested through substantial deployment experience. Z39.50 is one of the few examples we have to date of a protocol that actually goes beyond codifying mechanism and moves into the area of standardizing shared semantic knowledge. The extent to which this should be a goal of the protocol has been an ongoing source of controversy and tension within the developer community, and differing views on this issue can be seen both in the standard itself and the way that it is used in practice. Given the growing emphasis on issues such as "semantic interoperability" as part of the research agenda for digital libraries (see Clifford A. Lynch and Hector Garcia-Molina. Interoperability, Scaling, and the Digital Libraries Research Agenda, Report on the May 18-19, 1995 IITA Libraries Workshop, <http://www- diglib.stanford.edu/diglib/pub/reports/iita-dlw/main.html>), the insights gained by the Z39.50 community into the complex interactions among various definitions of semantics and interoperability are particularly relevant. The development process for the Z39.50 standard is also of interest in its own right. Its history, dating back to the 1970s, spans a period that saw the eclipse of formal standards-making agencies by groups such as the Internet Engineering Task Force (IETF) and informal standards development consortia. Moreover, in order to achieve meaningful implementation, Z39.50 had to move beyond its origins in the OSI debacle of the 1980s. Z39.50 has also been, to some extent, a victim of its own success -- or at least promise. Recent versions of the standard are highly extensible, and the consensus process of standards development has made it hospitable to an ever-growing set of new communities and requirements. As this process of extension has proceeded, it has become ever less clear what the appropriate scope and boundaries of the protocol should be, and what expectations one should have of practical interoperability among implementations of the standard. Z39.50 thus offers an excellent case study of the problems involved in managing the evolution of a standard over time. It may well offer useful lessons for the future of other standards such as HTTP and HTML, which seem to be facing some of the same issues.