Search (299 results, page 15 of 15)

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Content

Enthält die Beiträge: DIAZ, K.R.: Gatting started on the net; McGILLIS, L.: Gopher searching using Veronica; MARDIKIAN, J.: How to use Veronica to find information on the Internet; SMALL, J.J.: The Internet Goher: a reference tool; SCOTT, R.L.: Geoscience resources on the internet; MORGAN, K.A.: Economic and statistical information on the Internet; MAXYMUK, J.: Science resources on the Internet; KIBBEE, J.: A virtual library for librarians: JANET's bulletin board for libraries; NATALE, J.A.: Texas woman's university and White House communications on the Internet; POLLITZ, J.H.: Internet resources: opportunity knocks at the door; CROMER, D.E., M.E. JOHNSON: The impact of the Internet on communication among reference librarians; SILVA, M., G.F. CARTWRIGHT: The Internet and reference librarians: a question of leadership; HENDERSON, T.: MOOving towards a virtual reference service; ABELS, E.G., P. LIEBSCHER: A new challenge for intermediary-client communication: the electronic network; KALIN, S., C. WRIGHT: Internexus: a partnership for Internet instruction; STEPHENSON, N., D.J. WILLIS: Internet in-service training at the University of New Mexiko General Library; SANTAVICCA, E.F.: The Internet as a reference and research tool: a model for educators; ELLIOTT, C.S.: NREN update, 1993: Washington policy; STARR, S.S.: Evaluating physical science reference sources on the Internet; SEIDEN, P., K.A. NUCKOLLS: Developing a Campus-Wide Information System using the Gopher protocol: a study of collection development and classification issues; PERKINS, J.T.: The first mile down Internet I: development, training, and reference issues in the use of an X Windows interface for Internet access; NEUMAN, M., P. MANGIAFICO: Providing and accessing information via the Internet: the Georgetown catalogue of projects in electronic texts; PARKHURST, C.A., M.L. KWON: The Nevada Academic Libraries Information System: an application of Internet services; TOMER, C.: MIME and electronic reference services; STOREY, T.: The Internet and OCLC: broadening access to the world's information

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Content

Enthält die Beiträge: CORRALL, S.: Informations specialists of the future: professional development and renewal; BAUWENS, M.: Cyberspace, virtualization, and the role of cybrarians; DeVries, J.C. u. L.D. MINNIGH: Information specialists in the future academic library: flexible tightrope walkers; JONES, W.G.: Have librarians failed librarianship? A reply to Lancaster; WHITE, H.S.: The role of information intermediaries and the superhighway: crucial, important, trivial, or non-existent? ANDERSON, G.: MIT - the distributed library initiative: collaboration, vision, prototyping; EYRE, J.: The ELISE project: visual information retrieval and delivery; DAY, J.M., C. EDWARDS u. G. WALTON: IMPEL: a research project into the impact on people of electronic libraries - stage one - librarians; SIJTSMA, A.V:: The MECANO system: a mechanism of automatic comparison of CD-ROM answers with OPACs; NEDELA, R.: Managing CD changers of 6-777 CDs or a multiple of that with PeriLIB Library Controller; RITTER, G.: CD-ROM server in the Internet; TOROK, A.G.: Technological speedtraps on the information superhighway; FEDUNOK, S.: Internet One: The Binghampton University Libraries' interface to the Internet; BJÖRKLUND, L., R. HJERPPE u. A. BJÖRKLIND: Highways and backroads of Internet: strategies and tactics; NOERR, K.T:: Information superhighway in Singapore; BOSSMEYER, C. u. B. LUCHNER: DBV OSI II: open communication between library and information retrieval systems; WERF-DAVELAAR, T van der: Organizing fileservers on the Internet: role of the library: LANCASTER, F.W.: Networked electronic publishing of the results of scholarly research; KLUITERS, C.C.P.: CAPCAS as a route to the digital library; PLACE, T.W.: From online contents to online articles: developing new library services at Tilburg University; MITCHELL, J. u. P. HALBERG: End-user searching and document ordering: the experience with OCLC FirstSearch service; SIMON, R.: ALEPH: new approach to library system's architecture; LINE, M.B.: Who pays for information? And why should they? KLUGKIST, A.C.: Open library networking and interlibrary cooperation; STOKER, D. u. A. COOKE: Evaluation of networked information sources; RICHARD, S.: Driver education for the superhighway: CAL for end users; NIEUWENHUYSEN, P.: Development of slides about information retrieval, using a presentation software package; ANGILETTA, A.M.: Collection development in the large American Research Library: at an end or at a beginning? ARNOLD, K.: User aspects of the ELINOR electronic library; SANDORE, B.: Remote use of the virtual library: end user needs; REINITZER, S.: The function of a traditional library as a virtual library: a comparison; SEVER, S. u. C.H. HAREL: Managing the virtual library: issues and challenges; SEVER, I.: Academic library users and electronic retrieval systems; WALTON, J.: Conference summary

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Abstract

The theme of "Organizing the Internet" brings to mind the late 1950s folk-rock singer Jimmie Rodgers's song titled "The World I Used to Know." A great many developments have transpired in the world of information science since the seminal works of S. C. Bradford, Claude Shannon, Vannevar Bush, and numerous other pioneers. To those of us who have been in the information science field for several decades, the peek-a-boo devices such as Termatrex, Mortimer Taube's Uniterm cards, and discussion of pre- and postcoordinate indexing have given way to the world of browsers, HTML, XML, and numerous other ways of coding text and multimedia. The Internet and the World Wide Web have had a profound impact on how we go about storing and retrieving information. Document integrity has become transient, with little assurance that the location, existence, or even the content of a publication will be the same tomorrow as even a few minutes ago. We are often hard-pressed to determine if the failure to retrieve a publication is one associated with network infrastructure or the publisher. The dream of universal bibliographic control seems quite remote. By being able to bypass traditional publication channels, anyone can publish virtually at will. The situation becomes more chaotic when we consider the increasing redundancy of knowledge and the rampant proliferation of misinformation and disinformation, to say nothing of social concerns with pornography, copyright violations, and other flagrant obtrusions into personal rights. Nevertheless, it behooves the information worker and the information user to make some sense of order if good information is to remain the basis of learning and decision making, and if documents are to continue as an archive of human knowledge.

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Footnote

The economic opportunity divide is predicated an the hypothesis that there has, indeed, been a major shift in opportunities driven by changes in the information environment. The authors document this paradigm shift well with arguments from the political and economic right and left. This chapter might be described as an "attitudinal" chapter. The authors are concerned here with the perceptions of their respondents of their information skills and skill levels with their economic outlook and opportunities. Technological skills and economic opportunities are correlated, one finds, in the minds of all across all ages, genders, races, ethnicities, and income levels. African Americans in particular are ". . attuned to the use of technology for economic opportunity" (p. 80). The fourth divide is the democratic divide. The Internet may increase political participation, the authors posit, but only among groups predisposed to participate and perhaps among those with the skills necessary to take advantage of the electronic environment (p. 86). Certainly the Web has played an important role in disseminating and distributing political messages and in some cases in political fund raising. But by the analysis here, we must conclude that the message does not reach everyone equally. Thus, the Internet may widen the political participation gap rather than narrow it. The book has one major, perhaps fatal, flaw: its methodology and statistical application. The book draws upon a survey performed for the authors in June and July 2001 by the Kent State University's Computer Assisted Telephone Interviewing (CATI) lab (pp. 7-9). CATI employed a survey protocol provided to the reader as Appendix 2. An examination of the questionnaire reveals that all questions yield either nominal or ordinal responses, including the income variable (pp. 9-10). Nevertheless, Mossberger, Tolbert, and Stansbury performed a series of multiple regression analyses (reported in a series of tables in Appendix 1) utilizing these data. Regression analysis requires interval/ratio data in order to be valid although nominal and ordinal data can be incorporated by building dichotomous dummy variables. Perhaps Mossberger, Tolbert, and Stansbury utilized dummy variables; but 1 do not find that discussed. Moreover, 1 would question a multiple regression made up completely of dichotomous dummy variables. I come away from Virtual Inequality with mixed feelings. It is useful to think of the digital divide as more than one phenomenon. The four divides that Mossberger, Tolbert, and Stansbury offeraccess, skills, economic opportunity, and democratic-are useful as a point of departure and debate. No doubt, other divides will be identified and documented. This book will lead the way. Second, without question, Mossberger, Tolbert, and Stansbury provide us with an extremely well-documented, -written, and -argued work. Third, the authors are to be commended for the multidisciplinarity of their work. Would that we could see more like it. My reservations about their methodological approach, however, hang over this review like a shroud."
Anmerkung des Rezensenten in JASIST 55(2004) no.11, S.1024: "After reflecting an a requestfrom the authors of the reviewed book, 1 find that I did indeed err in my criticism of their methodology. The work's fault lies not with the methodology but rather with the discussion and explanation provided for the methodology. The authors do offer brief methodological explanation and justification in endnotes and appendices but are less clear in the book's text. I apologize to both the readers of the review and the authors for misinterpreting the text. For the authors' part, a methodology chapter would have been welcome. I am pleased to put right this misinterpretation that cast a shadow over an otherwise fine work."

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Content

Introduction: It's a people-driven economy, stupid -- Word of mouth goes world of mouth -- Social media = preventative behavior -- Social media = braggadocian behavior -- Obama's success driven by social media -- I care more about what my neighbor thinks than what Google thinks -- Death of social schizophrenia -- Winners and losers in a 140-character world -- Next step for companies and the "glass house generation" -- Socialnomics summary.

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Abstract

Information extraction systems discover structured information in natural language text. Having information in structured form enables much richer querying and data mining than possible over the natural language text. However, information extraction is a computationally expensive task, and hence improving the efficiency of the extraction process over large text collections is of critical interest. In this paper, we focus on an especially valuable family of text collections, namely, the so-called deep-web text collections, whose contents are not crawlable and are only available via querying. Important steps for efficient information extraction over deep-web text collections (e.g., selecting the collections on which to focus the extraction effort, based on their contents; or learning which documents within these collections-and in which order-to process, based on their words and phrases) require having a representative document sample from each collection. These document samples have to be collected by querying the deep-web text collections, an expensive process that renders impractical the existing sampling approaches developed for other data scenarios. In this paper, we systematically study the space of query-based document sampling techniques for information extraction over the deep web. Specifically, we consider (i) alternative query execution schedules, which vary on how they account for the query effectiveness, and (ii) alternative document retrieval and processing schedules, which vary on how they distribute the extraction effort over documents. We report the results of the first large-scale experimental evaluation of sampling techniques for information extraction over the deep web. Our results show the merits and limitations of the alternative query execution and document retrieval and processing strategies, and provide a roadmap for addressing this critically important building block for efficient, scalable information extraction.

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Footnote

Rez. in: nfd 54(2003) H.8, S.497 (T. Mandl): "Gesetze der digitalen Anarchie - Hyperlinks im Internet entstehen als Ergebnis sozialer Prozesse und können auch als formaler Graph im Sinne der Mathematik interpretiert werden. Die Thematik Hyperlinks ist im Information Retrieval höchst aktuell, da Suchmaschinen die Link-Struktur bei der Berechnung ihrer Ergebnisse berücksichtigen. Algorithmen zur Bestimmung des "guten Rufs" einer Seite wie etwa PageRank von Google gewichten eine Seite höher, wenn viele links auf sie verweisen. Barabási erklärt dem Leser seines Buches darüber hinaus noch, wie es zu solchen Phänomenen kommt. Soziale Prozesse im Netz wirken so, dass bereits bekannte Seiten mit größerer Wahrscheinlichkeit auch wieder weitere Links oder neue Besucher anziehen. Barabási ist Physiker an der Notre-Dame University und ihm fehlt ebenso wie Huberman die informationswissenschaftliche Perspektive. Er fragt also kaum, wie kann das Wissen über Netzwerke zu Verbesserungen in Informationssystemen führen, die Benutzerbedürfnisse besser erfüllen. Gleichwohl lohnt sich die Lektüre auch für Informationswissenschaftler. Barabäsi stellt die aktuelle Forschung zur Netzwerkstruktur des Internets auf einfache Weise fast ohne Zugeständnisse an Aktualität und Komplexität dar. Wie Huberman verzichtet auch er weitgehend auf Formeln und andere Formalismen. Der in Ungarn geborene Barabási lässt darüber hinaus keine Anekdote aus, sei es über die Begründer der Graphen-Theorie, im peer-review abgelehnte Beiträge und persönliche Begegnungen mit anderen Forschern. Barabási beginnt mit einfachen Netzwerkstrukturen und schreitet didaktisch über internet-ähnliche Netzwerke weiter zu Anwendungen und praktischen Beispielen aus unterschiedlichsten Disziplinen. Er schafft mit seinem Buch "Linked" unter anderem Links zwischen der ungarischen Literatur, dem I-Love-You Computer-Virus, der Verbreitung von Aids, den Theorien Einsteins, den Aufsichtsräten der wichtigsten amerikanischen Firmen, dem Al-Qaeda-Netzwerk und der Struktur und der Funktion biologischer Zellen. Zu Beginn seines Buches berichtet Barabási von sogenannten kleinen Welten, in denen viele Objekte über wenige Verbindungen zusammenhängen. Ein Blick in den eigenen größeren Bekanntenkreis mag bestätigen, dass viele Menschen über wenige Schritte zwischen Bekannten erreichbar sind. Sowohl Barabäsi als auch Huberman gehen auf die Geschichte des ersten sozialwissenschaftlichen Experiments zu diesem Thema ein, das in den 1960er Jahren versuchte, die Anzahl von Schritten zwischen gemeinsamen Bekannten zu bestimmen, welche vom Mittleren Westen der USA an die Ostküste führt. Die genauere Struktur solcher Systeme, in denen manche Knoten weitaus mehr Beziehungen zu anderen eingehen als der Durchschnitt, führt hin zum Internet. Im Web lässt sich keineswegs immer ein Pfad zwischen zwei Knoten finden, wie noch vor wenigen Jahren vermutet wurde. Die durchschnittliche Entfernung war damals noch mit 19 Klicks berechnet worden. Vielmehr herrscht eine differenziertere Struktur, die Barabási vorstellt und in der zahlreiche Seiten in Sackgassen führen. Huberman wie Barabási diskutieren auch negative Aspekte des Internet. Während Huberman die Wartezeiten und Staus bei Downloads analysiert, bespricht Barabási die rasante Verbreitung von ComputerViren und weist auf die Grundlagen für diese Gefährdung hin. Das vorletzte Kapitel widmen übrigens beide Autoren den Märkten im Internet. Spätestens hier werden die wirtschaftlichen Aspekte von Netzwerken deutlich. Beide Titel führen den Leser in die neue Forschung zur Struktur des Internet als Netzwerk und sind leicht lesbar. Beides sind wissenschaftliche Bücher, wenden sich aber auch an den interessierten Laien. Das Buch von Barabási ist etwas aktueller, plauderhafter, länger, umfassender und etwas populärwissenschaftlicher."

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Date

22. 9.1997 19:16:05

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Date

21. 4.2002 10:22:31

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Date

22.10.2006 10:22:33

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Footnote

Rez. in: Internet Professionell. 2000, H.2, S.22

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Date

22. 1.2011 17:54:04

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Date

20. 1.2015 18:30:22

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20. 1.2015 18:30:22

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Footnote

Relational database Management systems have been one of the great success stories of recent times and sensitive to the market, Most major vendors have responded by extending their products to handle XML data while still exploiting the range of facilities that a modern RDBMS affords. No book of this type would be complete without consideration of the "big these" (Oracle 9i, DB2, and SQL Server 2000 which each get a dedicated chapter) and though occasionally overtly piece-meal and descriptive the authors all note the shortcomings as well as the strengths of the respective systems. This part of the book is somewhat dichotomous, these chapters being followed by two that propose detailed solutions to somewhat theoretical problems, a generic architecture for storing XML in a RDBMS and using an object-relational approach to building an XML repository. The biography of the author of the latter (Paul Brown) contains the curious but strangely reassuring admission that "he remains puzzled by XML." The first five components are in-depth case studies of XMLdatabase applications. Necessarily diverse, few will be interested in all the topics presented but I was particularly interested in the first case study an bioinformatics. One of the twentieth century's greatest scientific undertakings was the Human Genome Project, the quest to list the information encoded by the sequence of DNA that makes up our genes and which has been referred to as "a paradigm for information Management in the life sciences" (Pearson & Soll, 1991). After a brief introduction to molecular biology to give the background to the information management problems, the authors turn to the use of XML in bioinformatics. Some of the data are hierarchical (e.g., the Linnaean classification of a human as a primate, primates as mammals, mammals are all vertebrates, etc.) but others are far more difficult to model. The Human Genome Project is virtually complete as far as the data acquisition phase is concerned and the immense volume of genome sequence data is no longer a very significant information Management issue per se. However bioinformaticians now need to interpret this information. Some data are relatively straightforward, e.g., the positioning of genes and sequence elements (e.g., promoters) within the sequences, but there is often little or no knowledge available an the direct and indirect interactions between them. There are vast numbers of such interrelationships; many complex data types and novel ones are constantly emerging, necessitating an extensible approach and the ability to manage semi-structured data. In the past, object databases such as AceDB (Durbin & Mieg, 1991) have gone some way to Meeting these aims but it is the combination of XML and databases that more completely addresses knowledge Management requirements of bioinformatics. XML is being enthusiastically adopted with a plethora of XML markup standards being developed, as authors Direen and Jones note "The unprecedented degree and flexibility of XML in terms of its ability to capture information is what makes it ideal for knowledge Management and for use in bioinformatics."
After several detailed examples of XML, Direen and Jones discuss sequence comparisons. The ability to create scored comparisons by such techniques as sequence alignment is fundamental to bioinformatics. For example, the function of a gene product may be inferred from similarity with a gene of known function but originating from a different organism and any information modeling method must facilitate such comparisons. One such comparison tool, BLAST utilizes a heuristic method has become the tool of choice for many years and is integrated into the NeoCore XMS (XML Management System) described herein. Any set of sequences that can be identified using an XPath query may thus become the targets of an embedded search. Again examples are given, though a BLASTp (protein) search is labeled as being BLASTn (nucleotide sequence) in one of them. Some variants of BLAST are computationally intensive, e.g., tBLASTx where a nucleotide sequence is dynamically translated in all six reading frames and compared against similarly translated database sequences. Though these variants are implemented in NeoCore XMS, it would be interesting to see runtimes for such comparisons. Obviously the utility of this and the other four quite specific examples will depend an your interest in the application area but two that are more research-oriented and general follow them. These chapters (on using XML with inductive databases and an XML warehouses) are both readable critical reviews of their respective subject areas. For those involved in the implementation of performance-critical applications an examination of benchmark results is mandatory, however very few would examine the benchmark tests themselves. The picture that emerges from this section is that no single set is comprehensive and that some functionalities are not addressed by any available benchmark. As always, there is no Substitute for an intimate knowledge of your data and how it is used. In a direct comparison of an XML-enabled and a native XML database system (unfortunately neither is named), the authors conclude that though the native system has the edge in handling large documents this comes at the expense of increasing index and data file size. The need to use legacy data and software will certainly favor the all-pervasive XML-enabled RDBMS such as Oracle 9i and IBM's DB2. Of more general utility is the chapter by Schmauch and Fellhauer comparing the approaches used by database systems for the storing of XML documents. Many of the limitations of current XML-handling systems may be traced to problems caused by the semi-structured nature of the documents and while the authors have no panacea, the chapter forms a useful discussion of the issues and even raises the ugly prospect that a return to the drawing board may be unavoidable. The book concludes with an appraisal of the current status of XML by the editors that perhaps focuses a little too little an the database side but overall I believe this book to be very useful indeed. Some of the indexing is a little idiosyncratic, for example some tags used in the examples are indexed (perhaps a separate examples index would be better) and Ron Bourret's excellent web site might be better placed under "Bourret" rather than under "Ron" but this doesn't really detract from the book's qualities. The broad spectrum and careful balance of theory and practice is a combination that both database and XML professionals will find valuable."

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Classification

303.48/33 22 (LoC)

DDC

303.48/33 22 (LoC)

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Date

22. 3.2004 14:46:50