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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An informetric study of the distribution of bibliographic records in online databases: a case study using the literature of Fuzzy Set Theory (1965-1993)

Hood, William, School of Information Library & Archive Studies, UNSW January 1999 (has links)
This study investigated the distribution of bibliographic records amongst online bibliographic databases. The topic of Fuzzy Set Theory over the period of 1965 to 1993 was chosen to provide the case study for this investigation. From the DIALOG database host, searches were conducted on 114 databases to determine the number of journal article records relating to the topic of Fuzzy Sets. Both the number of records in each database, as well as the overlap of coverage between the databases were calculated. Six counting techniques were developed to allocate records to databases based on different methods for handling records that were duplicated between databases. When duplicate records are included, the top database accounts for 19% of the records; when duplicates are removed, the top database was found to account for 37% of the records. The distribution of records in databases was found to conform to the Bradford-Zipf hyperbolic distribution. Various other analyses were undertaken including: the duplicate records themselves, the total size of the DIALOG database system over time and the density of Fuzzy Set records in databases over time. A secondary aim of this study was to perform an informetric study on the literature of Fuzzy Set Theory itself. Results obtained include an analysis of the growth of the Fuzzy Set literature, an analysis of the journals covering the topic of Fuzzy Sets, an analysis of the terminology used in describing topics related to Fuzzy Sets. Also, the Ulrich's database was used to provide a subject classification of the journals to analyse the diffusion of the topic of Fuzzy Sets into other disciplines. Apart from the discipline of mathematics, the top disciplines into which Fuzzy Sets have diffused were found to be applied physics, systems and computing. The third aim of the thesis was to refine and develop the methodology used to perform large scale informetric studies using data from a variety of online bibliographic databases. Commercially available software was used wherever possible, but where this was not possible or infeasible, custom written programs were developed to perform various steps in the methodology.
2

A descriptive study of statewide bibliographic databases

Gardner, Stan (Stan A.) 08 1900 (has links)
This dissertation has compiled information about statewide bibliographic databases, their format, their cost, the number of titles and records, how they are being used, what kinds of libraries are using such databases in each state and the effectiveness of those databases.
3

Where Google Scholar Stands on Art: An Evaluation of Content Coverage in Online Databases

Hannah M. Noll 2008 April 1900 (has links)
This study evaluates the content coverage of Google Scholar and three commercial databases (Arts & Humanities Citation Index, Bibliography of the History of Art and Art Full Text/Art Index Retrospective) on the subject of art history. Each database is tested using a bibliography method and evaluated based on Péter Jacsó’s scope criteria for online databases. Of the 472 articles tested, Google Scholar indexed the smallest number of citations (35%), outshone by the Arts & Humanities Citation Index which covered 73% of the test set. This content evaluation also examines specific aspects of coverage to find that in comparison to the other databases, Google Scholar provides consistent coverage over the time range tested (1975-2008) and considerable access to article abstracts (56%). Google Scholar failed, however, to fully index the most frequently cited art periodical in the test set, the Artforum International. Finally, Google Scholar’s total citation count is inflated by a significant percentage (23%) of articles which include duplicate, triplicate or multiple versions of the same record.
4

Lituanistikos informacinė sistema / Information system “Lituanistika”

Kučiukas, Tomas 26 August 2010 (has links)
Šio darbo tyrimo sritis – programinės įrangos projektavimo metodai, leidžiantys išplėsti egzistuojančias sistemas, ir jų taikymas bibliotekų informacinei sistemai. Tyrimo objektas – mokslo publikacijų, atitinkančių lituanistikos sampratą, bibliografinės duomenų bazės projektavimas ir kūrimas. Darbo tikslas – pagerinti lituanistikos sampratą atitinkančių mokslo publikacijų vertinimo bei sklaidos galimybes, automatizuoti šių publikacijų pateikimo, ekspertavimo bei sklaidos procesus. / International social and humanitarian science and abstract bibliographic databases includes the most important and most significant of these documents in scientific fields. Databases developed thematically (eg, MLA International Bibliography, Sociological Abstracts CSA) and / or regional basis (eg, British Humanities Index). Search of international databases are a great tool for quickly and efficiently find information about the world of the studies performed and published scholarly works in the social and humanitarian sciences publications. Lithuanian academic journals and research publications in international databases is increasing in recent years, but in Lithuania the tests and researchers work to develop international databases is only fragmentary. International social and humanitarian sciences databases of lithuanistic ensure the development of Lithuanian scientists work visibility in national and international level and at the same scientists laid down in recognition of excellence. This database should be based on best international social and humanitarian experience of databases.
5

A conceptual framework for information management : formation of a discipline

Middleton, Michael Robert January 2007 (has links)
The aim of the research was to investigate the formation of the information management discipline, propose a framework by which it is presently understood, and test that framework within a particular area of application, namely the provision of scientific and technological information (STI) services. The work is presented as a PhD by Publication which comprises a narrative that encompasses the series of published papers, and includes excerpts from the book written to illustrate the province of the discipline. In thee book the disciplinary context is detailed and exemplified based upon information management domains. The book consolidates information management principles within a framework defined by these operational, analytical and administrative domains. It was created by a redaction of prior epistemological proposals; an analysis of the understanding of practice that has been shaped by professional, institutional and information science influences; and demonstration of practice within the domain framework. The disciplinary framework was then used in a series of STI case studies where it was found to provide an effective description of information management. Together, the book and subsequent case studies provided illustration of the principles utilised in information management and the way that they are practiced within different domains, along with an explanation of the manner in which the information management discipline has been formed. These should assist with direction of future research and scholarship particularly with respect to factors relevant to information services and indicators for their successful application in future. It is anticipated that this generalised description of the practices across the range of interpretations of information management should enable practicing information professionals to appreciate the relationship of their own work to disciplines that are converging towards similar purpose, such as through a clearer indication of the extent to which technical and management standards may be applied, and performance analysis undertaken. Complementary outcomes that were achieved during the course of the work were: a comparative analysis of thesauri in the information field which shows that in this field, the ways that information professionals represent themselves remains unreconciled; an historical examination of Australian STI services that provides pointers to their effective continuation; and a reconsideration of the relationship between librarianship and information management. The work is presented as a compilation of papers that comprise firstly extracts from the book to exemplify its consolidation of information management principles, then a number of published and submitted papers that examine how principles have been applied in practice. This is in the context of six case studies of Australian STI services including interviews with creators and developers, and analysis of historical information.
6

Analýza systému Medline/PubMed / Analysis of Medline/PubMed

Vejvoda, Tomáš January 2016 (has links)
The diploma thesis examines biomedicine bibliographic databases MEDLINE and PubMed, both developed, maintained and provided by the U. S. National Library of Medicine (NLM). A general goal of thesis is offering answers to the question of historical and current importance of these resources. Text deals with a historical context of databases formation and their reflection in Czechoslovakian and Czech scientific community, what is also supported by qualitative research conducted as part of the thesis. Main part of the thesis deals with comprehensive analysis of the databases within environment formed by the NLM; analysis of systems components and PubMed graphic user interface and its query language. The thesis also presents issues of accessing databases content through third parties alternative platforms or interfaces built upon E-Utilities API. In the end, thesis offers ideas on probable development of MEDLINE and PubMed databases in the near and distant future. Powered by TCPDF (www.tcpdf.org)
7

Considerations for Identifying and Conducting Cluster Randomized Trials / Considerations For Identifying and Conducting Cluster Trials

Al-Jaishi, Ahmed January 2021 (has links)
Background: The cluster randomized trial design randomly assigns groups of people to different treatment arms. This dissertation aimed to (1) develop machine learning algorithms to identify cluster trials in bibliographic databases, (2) assess reporting of methodological and ethical elements in hemodialysis-related cluster trials, and (3) assess how well two covariate-constrained randomization methods balanced baseline characteristics compared with simple randomization. Methods: In study 1, we developed three machine learning algorithms that classify whether a bibliographic citation is a CRT report or not. We only used the information available in an article citation, including the title, abstract, keywords, and subject headings. In study 2, we conducted a systematic review of CRTs in the hemodialysis setting to review the reporting of key methodological and ethical issues. We reviewed CRTs published in English between 2000 and 2019 and indexed in MEDLINE or EMBASE. In study 3, we assessed how well two covariate-constrained randomization methods balanced baseline characteristics compared with simple randomization. Results: In study 1, we successfully developed high-performance algorithms that identified whether a citation was a CRT. Our algorithms had greater than 97% sensitivity and 77% specificity in identifying CRTs. For study 2, we found suboptimal conduct and reporting of methodological issues of CRTs in the hemodialysis setting and incomplete reporting of key ethical issues. For study 3, where we randomized 72 clusters, constraining the randomization using historical information achieved a better balance on baseline characteristics than simple randomization; however, the magnitude of benefit was modest. Conclusions: This dissertation's results will help researchers quickly identify cluster trials in bibliographic databases (study 1) and inform the design and analyses of future Canadian trials conducted within the hemodialysis setting (study 2 & 3). / Thesis / Doctor of Philosophy (PhD) / The cluster trial design randomly assigns groups of people to different treatment arms rather than individuals. Cluster trials are commonly used in research areas such as education, public health, and health service research. Examples of clusters can include villages/communities, worksites, schools, hospitals, hospital wards, and physicians. This dissertation aimed to (1) develop machine learning algorithms to identify cluster trials in bibliographic databases, (2) assess reporting of methodological and ethical elements in hemodialysis-related cluster trials, and (3) identified best practices for randomly assigning hemodialysis centers in cluster trials. We conducted three studies to address these aims. The results of this dissertation will help researchers quickly identify cluster trials in bibliographic databases (study 1) and inform the design and analyses of future Canadian trials conducted within the hemodialysis setting (study 2 & 3).
8

Databáze a digitální knihovny pro farmaceutické obory / Databases and digital libraries for pharmaceutical disciplines

Kebza, Vladimír January 2014 (has links)
The aim of the diploma thesis is to describe and basically analyze representative databases and digital libraries that focus on pharmaceutical disciplines. The introductory chapter is concerned with related terminology, while the following chapters refer to significant subjects and principles in the field of pharmaceutical industry, and also to important classification systems and retrieval languages that can be found in some of the described resources. The fifth chapter focuses on pharmaceutical information resources which are offered by some of the world's leading database service companies. The sixth chapter contains a description and a basic analysis of 10 representative electronic resources for pharmaceutical disciplines. The empirical section of this diploma thesis consists of three major parts. One of them is a subject coverage analysis of bibliographic databases MEDLINE and EMBASE from the viewpoint of pharmaceutical information. Secondly, it contains a presentation of an indicative survey that is related to using electronic information resources by a commercial and a nonprofit subject. The last chapter deals with information brokering that is presented on example of the Medistyl company. Keywords Pharmaceutical industry, pharmacy, pharmacovigilance, factographic databases, bibliographic...
9

Re-Ranking auf Basis von Bradfordizing für die verteilte Suche in digitalen Bibliotheken

Mayr, Philipp 06 March 2009 (has links)
Trotz großer Dokumentmengen für datenbankübergreifende Literaturrecherchen erwarten akademische Nutzer einen möglichst hohen Anteil an relevanten und qualitativen Dokumenten in den Trefferergebnissen. Insbesondere die Reihenfolge und Struktur der gelisteten Ergebnisse (Ranking) spielt, neben dem direkten Volltextzugriff auf die Dokumente, inzwischen eine entscheidende Rolle beim Design von Suchsystemen. Nutzer erwarten weiterhin flexible Informationssysteme, die es unter anderem zulassen, Einfluss auf das Ranking der Dokumente zu nehmen bzw. alternative Rankingverfahren zu verwenden. In dieser Arbeit werden zwei Mehrwertverfahren für Suchsysteme vorgestellt, die die typischen Probleme bei der Recherche nach wissenschaftlicher Literatur behandeln und damit die Recherchesituation messbar verbessern können. Die beiden Mehrwertdienste semantische Heterogenitätsbehandlung am Beispiel Crosskonkordanzen und Re-Ranking auf Basis von Bradfordizing, die in unterschiedlichen Phasen der Suche zum Einsatz kommen, werden hier ausführlich beschrieben und im empirischen Teil der Arbeit bzgl. der Effektivität für typische fachbezogene Recherchen evaluiert. Vorrangiges Ziel der Promotion ist es, zu untersuchen, ob das hier vorgestellte alternative Re-Rankingverfahren Bradfordizing im Anwendungsbereich bibliographischer Datenbanken zum einen operabel ist und zum anderen voraussichtlich gewinnbringend in Informationssystemen eingesetzt und dem Nutzer angeboten werden kann. Für die Tests wurden Fragestellungen und Daten aus zwei Evaluationsprojekten (CLEF und KoMoHe) verwendet. Die intellektuell bewerteten Dokumente stammen aus insgesamt sieben wissenschaftlichen Fachdatenbanken der Fächer Sozialwissenschaften, Politikwissenschaft, Wirtschaftswissenschaften, Psychologie und Medizin. Die Evaluation der Crosskonkordanzen (insgesamt 82 Fragestellungen) zeigt, dass sich die Retrievalergebnisse signifikant für alle Crosskonkordanzen verbessern; es zeigt sich zudem, dass interdisziplinäre Crosskonkordanzen den stärksten (positiven) Effekt auf die Suchergebnisse haben. Die Evaluation des Re-Ranking nach Bradfordizing (insgesamt 164 Fragestellungen) zeigt, dass die Dokumente der Kernzone (Kernzeitschriften) für die meisten Testreihen eine signifikant höhere Precision als Dokumente der Zone 2 und Zone 3 (Peripheriezeitschriften) ergeben. Sowohl für Zeitschriften als auch für Monographien kann dieser Relevanzvorteil nach Bradfordizing auf einer sehr breiten Basis von Themen und Fragestellungen an zwei unabhängigen Dokumentkorpora empirisch nachgewiesen werden. / In spite of huge document sets for cross-database literature searches, academic users expect a high ratio of relevant and qualitative documents in result sets. It is particularly the order and structure of the listed results (ranking) that play an important role when designing search systems alongside the direct full text access for documents. Users also expect flexible information systems which allow influencing the ranking of documents and application of alternative ranking techniques. This thesis proposes two value-added approaches for search systems which treat typical problems in searching scientific literature and seek to improve the retrieval situation on a measurable level. The two value-added services, semantic treatment of heterogeneity (the example of cross-concordances) and re-ranking on Bradfordizing, which are applied in different search phases, are described in detail and their effectiveness in typical subject-specific searches is evaluated in the empirical part of the thesis. The preeminent goal of the thesis is to study if the proposed, alternative re-ranking approach Bradfordizing is operable in the domain of bibliographic databases, and if the approach is profitable, i.e. serves as a value added, for users in information systems. We used topics and data from two evaluation projects (CLEF and KoMoHe) for the tests. The intellectually assessed documents come from seven academic abstracting and indexing databases representing social science, political science, economics, psychology and medicine. The evaluation of the cross-concordances (82 topics altogether) shows that the retrieval results improve significantly for all cross-concordances, indicating that interdisciplinary cross-concordances have the strongest (positive) effect on the search results. The evaluation of Bradfordizing re-ranking (164 topics altogether) shows that core zone (core journals) documents display significantly higher precision than was seen for documents in zone 2 and zone 3 (periphery journals) for most test series. This post-Bradfordizing relevance advantage can be demonstrated empirically across a very broad basis of topics and two independent document corpora as well for journals and monographs.
10

Construction et validation de filtres de recherche bibliographique pour soutenir la prise de décisions basée sur les évidences : le cas de la sécurité des patients.

Tanon, Affaud A. 10 1900 (has links)
Les filtres de recherche bibliographique optimisés visent à faciliter le repérage de l’information dans les bases de données bibliographiques qui sont presque toujours la source la plus abondante d’évidences scientifiques. Ils contribuent à soutenir la prise de décisions basée sur les évidences. La majorité des filtres disponibles dans la littérature sont des filtres méthodologiques. Mais pour donner tout leur potentiel, ils doivent être combinés à des filtres permettant de repérer les études couvrant un sujet particulier. Dans le champ de la sécurité des patients, il a été démontré qu’un repérage déficient de l’information peut avoir des conséquences tragiques. Des filtres de recherche optimisés couvrant le champ pourraient s’avérer très utiles. La présente étude a pour but de proposer des filtres de recherche bibliographique optimisés pour le champ de la sécurité des patients, d’évaluer leur validité, et de proposer un guide pour l’élaboration de filtres de recherche. Nous proposons des filtres optimisés permettant de repérer des articles portant sur la sécurité des patients dans les organisations de santé dans les bases de données Medline, Embase et CINAHL. Ces filtres réalisent de très bonnes performances et sont spécialement construits pour les articles dont le contenu est lié de façon explicite au champ de la sécurité des patients par leurs auteurs. La mesure dans laquelle on peut généraliser leur utilisation à d’autres contextes est liée à la définition des frontières du champ de la sécurité des patients. / Optimized bibliographic search filters are designed to facilitate information retrieval in bibliographic databases, which are almost always the most abundant source of scientific evidence. The purpose of such filters is to support evidence-based decision making. Many of the filters available in the literature are methodological search filters. To reach their full potential they need to be combined with subject filters that identify studies covering a particular topic. In the field of patient safety, it has been demonstrated that deficiencies in the information retrieval process can lead to tragic consequences. Optimized bibliographic search filters covering the field could thus be very useful. This study is intended to provide subject bibliographic search filters optimized for the field of patient safety, assess their validity, and offer a guide for developing optimized bibliographic search filters. We propose high-performing bibliographic search filters to retrieve papers dealing with patient safety in health care organizations, that have been explicitly defined as relevant to the patient safety field by their authors, in Medline, Embase and CINAHL. The main generalization issue lies in defining the boundaries of the patient safety field.

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