Search (4850 results, page 2 of 243)

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Abstract

Interdisciplinary research has been identified as a critical means of addressing some of our planet's most urgent environmental problems. Yet relatively little is known about the processes and impact of interdisciplinary approaches to environmental sciences. This study used citation analysis and ordinary least squares regression to investigate the relationship between an article's citation rate and its degree of interdisciplinarity in one area of environmental science; viz., forestry. 3 types of interdisciplinarity were recognized - authorspip, subject matter, and cited literature - and each was quantified using Brillouin's diversity index. Data consisted of more than 750 articles published in the journal 'Forest Science' during the 10year period 1985-1994. The results indicate that borrowing was the most influencial method of interdisciplinary information transfer. Articles that drew information from a diverse set of journals were cited with greater frequency than articles having smaller or more narrowly focused bibliographies. This finding provides empirical evidence that interdisciplinary methods have made a measurable and positive impact on the forestry literature

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Abstract

Individual differences between users of information systems can influence search performance. In user-centered design it is important to match users with system configurations that will optimize their performance. 2 matching strategies were explored in the first experiment: the capitalization match, and the compensatory match. Findings suggest that a compensatory match is likely to be encountered more frequently in designing information systems. Having determined an optimal match between users and systems configurations, it is necessary to find ways to ensure that users are guided to the appropriate configuration. The second experiment examined user selection of system configurations, and concluded that users do not act to optimize system configuration when they select features. This result suggests that information systems must have mechanisms such as user models to direct users to optimal configurations. These experiments suggest some of the complexities and problems encountered in applying individual differences research to user-centered design of information systems

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Abstract

We describe a novel inference method to help us deal with the problem of having sparse information about the user. The information we will have available for the user will form his/her model. That model will be represented in a conceptual graph format. We will also have gathered information about categories of users that share characteristics, preferences and interests. These will form the "prototypes", as we call them and will be represented in graphs as well. Because we will know significantly more about the prototypes, they will be the source where we will try to get the information we want for the user. This method has been implemented in FRIL

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Abstract

We introduce a technique for creating novel, enhanced thumbnails of Web pages. These thumbnails combine the advantages of plain thumbnails and text summaries to provide consistent performance on a variety of tasks. We conducted a study in which participants used three different types of summaries (enhanced thumbnails, plain thumbnails, and text summaries) to search Web pages to find several different types of information. Participants took an average of 67, 86, and 95 seconds to find the answer with enhanced thumbnails, plain thumbnails, and text summaries, respectively. As expected, there was a strong effect of question category. For some questions, text summaries outperformed plain thumbnails, while for other questions, plain thumbnails outperformed text summaries. Enhanced thumbnails (which combine the features of text summaries and plain thumbnails) had more consistent performance than either text summaries or plain thumbnails, having for all categories the best performance or performance that was statistically indistinguishable from the best

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Abstract

MEDLINE is a collection of more than 12 million references and abstracts covering recent life science literature. With its continued growth and cutting-edge terminology, spell-checking with a traditional lexicon based approach requires significant additional manual followup. In this work, an internal corpus based context quality rating a, frequency, and simple misspelling transformations are used to rank words from most likely to be misspellings to least likely. Eleven-point average precisions of 0.891 have been achieved within a class of 42,340 all alphabetic words having an a score less than 10. Our models predict that 16,274 or 38% of these words are misspellings. Based an test data, this result has a recall of 79% and a precision of 86%. In other words, spell checking can be done by statistics instead of with a dictionary. As an application we examine the time history of low a words in MEDLINE titles and abstracts.

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Abstract

Actually information services cannot work ably without web functionalities. Archives are paradigmatic examples of information systems with low use of technological possibilities. A small but hopeful step forward is the electronic encoding of descriptive information. One tool made suitable for it is a DTD - SGML for instruments of archive description named EAD (Encoded Archival Description ). Having a base in an international norm like SGML, this tool, makes the information interchange. Possible. In this work Microsoft Active Server Pages encounter a concrete method for the automatic labeling of instruments of file description utilizing the displaced to one side programming technology of the server. Although the method develops in aggregate utilizing Microsoft technology, it can be utilized in another platforms, since the result generated is a document labeled in ASCII, to plain text, and therefore easily transferable to other platforms.

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Abstract

The purpose of this paper is to explore the feasibility of using a business process model as a framework for the integrated organization of electronic information in the context of business enterprises in general, and more specifically in the SMME sector in South Africa. An SMME is defined as a separate and distinct business entity, managed by one owner or more, and having less than 100 employees. Information organization in the business environment is described within the framework of three contexts, namely (1) document creation, (2) collections of documents, and (3) information retrieval systems consisting of document surrogates. Internal and extemal information resources typically found in business enterprises are categorized according to their relationships with business processes. It is concluded that it is theoretically feasible to organize resources in SMMMs according to a business process model.

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Abstract

With this title, readers learn to push the search engine to its limits and extract the best content from Google, without having to learn complicated code. "Google Power" takes Google users under the hood, and teaches them a wide range of advanced web search techniques, through practical examples. Its content is organised by topic, so reader learns how to conduct in-depth searches on the most popular search topics, from health to government listings to people.

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Abstract

This paper describes the efforts at the Daniel Cosio Villegas Library of Colegio de Mexico (Mexico) to create a Spanish language authority file on its ALEPH online system. To date, the authorities team, composed of about ten librarians, have created over 10,000 name authorities, and close to 4,000 subject authorities in MARC format, closely following the structure of the Library of Congress Subject Headings (LCSH) records. For the subject authority file, it was decided to establish three levels of description, all of which include the LCSH English term. In order to establish the term in Spanish, seven official sources have been used, with Bilindex (1984) having the highest usage, closely followed by the subject headings list developed by Consejo Superior de Investigaciones Cientificas (CSIC) of Spain. As the first Mexican NACO/SACO participants, librarians at the Colegio de Mexico Library also received training by personnel from the Library of Congress in the creation and validation of subject headings.

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Abstract

The article describes the research done over a bibliographic database in order to show the impact the specificity of the knowledge organising tools may have on information retrieval (IR). For this purpose two multilingual Universal Decimal Classification (UDC) based thesauri having different degrees of specificity are considered. Issues of harmonising a classificatory structure with a thesaurus structure are introduced, and significant aspects of information retrieval in a multilingual environment are examined in an extensive manner. Aspects of complementarity are discussed with particular emphasis on the real impact produced on IR by alternative search facilities. Finally, a number of conclusions are formulated as they arise from the study.

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Abstract

In this article the relationship between classification/indexing and retrieval is discussed. In library and information science, classification and retrieval have always been closely associated with each other. But in certain ages, because of a lack of interest in applying knowledge, it was thought that libraries were just a place for gathering and keeping books and other documents as assets. And therefore, people thought that classification was simply for arrangement, in order to have a kind of system for objects that they considered to be luxuries. The reason for this lies in their static view of things, including libraries. Changing attitudes and having a dynamic view of the world of reality will change everything. Thus, if we define that the library is not only a place for book collection but is a place where people fill their information needs, and also that librarianship is not mainly about classification, but is a discipline by which we retrieve information and receive knowledge, we may see a great change in the retrieval process.

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Abstract

In this article the relationship between classification/indexing and retrieval is discussed. In library and information science, classification and retrieval have always been closely associated with each other. But in certain ages, because of a lack of interest in applying knowledge, it was thought that libraries were just a place for gathering and keeping books and other documents as assets. And therefore, people thought that classification was simply for arrangement, in order to have a kind of system for objects that they considered to be luxuries. The reason for this lies in their static view of things, including libraries. Changing attitudes and having a dynamic view of the world of reality will change everything. Thus, if we define that the library is not only a place for book collection but is a place where people fill their information needs, and also that librarianship is not mainly about classification, but is a discipline by which we retrieve information and receive knowledge, we may see a great change in the retrieval process.

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Abstract

Catalogers in larger libraries have web access on their desktops, which puts many resources just a click away. Cataloging tools and documentation are available through web browser interfaces. Many library online catalogs are accessible for searching class numbers and other cataloging information. Web sites of publishers, governmental agencies, and individual authors abound, providing a wealth of information. Having this information readily available has had an impact on cataloging. The ability to have more than one open window on the desktop enables catalogers to copy and paste cataloging information from multiple sources. Web resources provide critical information about the context for the item in hand, resulting in better cataloging records and more accurate access points. This article discusses and gives examples of ways that information found on the web can be used to facilitate cataloging processes.

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Abstract

To celebrate the 20th anniversary of LITA/ALCTS CCS Authority Control in the Online Environment Interest Group (ACIG), a survey was sent out to its past chairs to identify the major issues concerning authority control during their tenure as chair, ACIG's major accomplishments during the year, and comments the past ACIG chairs had on the current focus and challenges for authority control in the future. The author discovered that since ACIG's creation in 1984 by Barbara Tillett, ACIG has contributed greatly to the field of authority control by addressing timely authority control topics with programs, discussions, and publications for the library community. ACIG meetings have always been well attended. ALL ACIG chairs were very proud to be part of having contributed to authority control and quite a few of them have been working very hard to promote authority control issues ever since.

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Abstract

In an attempt to ascertain whether academic libraries were having difficulty in filling cataloging positions, a survey was designed and distributed to those libraries that advertised for full-time cataloging positions in College and Research Libraries News between July 2000 and June 2002. While a number of studies done in the last decade had examined the content of job advertisements, this study tried to determine the actual outcomes of individual library searches by contacting libraries that had advertised. Using a web-based questionnaire, the authors queried these institutions on their recruitment process and hiring success. The results of this survey provided confirmation of a continued, if not increasing, difficulty in recruiting catalogers for academic libraries. Some implications for a wider debate on library school training and the general direction of the profession are discussed.

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Abstract

The present analysis looks at how scientists use the Internet for informal scientific communication. It investigates the relationship between several explanatory variables and Internet use in a cross-section of scientists from seven European countries and five academic disciplines (astronomy, chemistry, computer science, economics, and psychology). The analysis confirmed some of the results of previous U.S.-based analyses. In particular, it corroborated a positive relationship between research productivity and Internet use. The relationship was found to be nonlinear, with very productive (nonproductive) scientists using the Internet less (more) than would be expected according to their productivity. Also, being involved in collaborative R&D and having large networks of collaborators is associated with increased Internet use. In contrast to older studies, the analysis did not find any equalizing effect whereby higher Internet use rates help to overcome the problems of potentially disadvantaged researchers. Obviously, everybody who wants to stay at the forefront of research and keep upto-date with developments in their research fields has to use the Internet.

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Abstract

Indexing and abstracting are not activities that should be looked upon as ends in themselves. It is the results of these activities that should be evaluated and this can only be done within the context of a particular database, whether in printed or machine-readable form. In this context, the indexing can be judged successful if it allows searchers to locate items they want without having to look at many they do not want. This book intended primarily as a text to be used in teaching indexing and abstracting of Library and information science. It is an immense value to all individuals and institutions involved in information retrieval and related activities, including librarians, managers of information centres and database producers.

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Abstract

The Bibliographic Control Division of the International Federation of Library Associations and Institutions (IFLA) consists of three sections: bibliography, cataloguing, and classification. The cataloguing section, which focuses on descriptive cataloguing, is one of the oldest within IFLA, having been founded in 1935 as the IFLA Committee on Uniform Cataloguing Rules. It became the Committee on Cataloguing in 1970. The committee played a key role in planning and convening the International Conference on Cataloguing Principles held in Paris in 1961 and the International Meeting of Cataloguing Experts held in Copenhagen in 1969. The Copenhagen conference provided the impetus to develop the International Standard Bibliographic Descriptions (ISBD). The Committee on Cataloguing established a systematic process for the revision of the ISBDs. The cataloguing section focuses on traditional cataloguing standards and on the impact of electronic resources and technology on these standards. The section has initiated several projects at the international level to facilitate access to information.

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Abstract

One general principle in the construction of classification schemes is that of grouping phenomena to be classified according to their shared origin in evolution or history (phylogenesis). In general schemes, this idea has been applied by several classificationists in identifying a series of integrative levels, each originated from the previous ones, and using them as the main classes. In special schemes, common origin is a key principle in many domains: examples are given from the classification of climates, of organisms, and of musical instruments. Experience from these domains, however, suggests that using common origin alone, as done in cladistic taxonomy, can produce weird results, like having birds as a subclass of reptiles; while the most satisfying classifications use a well balanced mix of common origin and similarity. It is discussed how this could be applied to the development of a general classification of phenomena in an emergentist perspective, and how the resulting classification tree could be structured. Charles Bennett's notion of logical depth appears to be a promising conceptual tool for this purpose.