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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.
591

University Students and the Internet: Information Seeking Study

Shamo, Esmaeel 05 1900 (has links)
This study explored university students' information needs and seeking behaviors on the Internet. A Web-based survey was administrated one time. Two hundred responses were received from the target sample within the two weeks period of the study. Data were analyzed with descriptive statistics, factor analysis, and graphical representation. The study explored various issues related to the usability, preferences, and activities of the Internet, such as searching tools, e-mail, search engines, and preferred primary sources of everyday-life information needs. The study explored the perceptions of the students toward the Internet and the traditional library. Kuhlthau's model of the information-seeking process, which includes six stages and affective components, was utilized and modified in the construction of the Web survey. A study by Presno (1998), which includes the four types of Internet anxiety, was utilized in the construction of the Web survey. With regard to the six stages of Kuhlthau model, the majority of the respondents experienced stage 5, which was about information gathering; stage 3 had the next highest number of respondents. Very few respondents experienced stages 1 and 2. There was a systematic pattern in which, the earlier the stages the respondents were in, the more negative adjectives they selected, and vice versa. The feeling adjectives section showed a difference in the behavior between males and females. The results indicated that most students had Internet time delay anxiety. In general, the study found that students have a great interest in the Internet and consider it an important source of information for their personal, educational, and communication activities.
592

Children's Color Association for Digital Image Retrieval.

Chang, Yun-Ke 08 1900 (has links)
In the field of information sciences, attention has been focused on developing mature information retrieval systems that abstract information automatically from the contents of information resources, such as books, images and films. As a subset of information retrieval research, content-based image retrieval systems automatically abstract elementary information from images in terms of colors, shapes, and texture. Color is the most commonly used in similarity measurement for content-based image retrieval systems. Human-computer interface design and image retrieval methods benefit from studies based on the understanding of their potential users. Today's children are exposed to digital technology at a very young age, and they will be the major technology users in five to ten years. This study focuses on children's color perception and color association with a controlled set of digital images. The method of survey research was used to gather data for this exploratory study about children's color association from a children's population, third to sixth graders. An online questionnaire with fifteen images was used to collect quantitative data of children's color selections. Face-to-face interviews investigated the rationale and factors affecting the color choices and children's interpretation of the images. The findings in this study indicate that the color children associated with in the images was the one that took the most space or the biggest part of an image. Another powerful factor in color selection was the vividness or saturation of the color. Colors that stood out the most generally attracted the greatest attention. Preferences of color, character, or subject matter in an image also strongly affected children's color association with images. One of the most unexpected findings was that children would choose a color to replace a color in an image. In general, children saw more things than what were actually represented in the images. However, the children's interpretation of the images had little effect on their color selections.
593

The gathering and use of information by fifth grade students with access to Palm® handhelds.

Peet, Martha Stuart Williamson 12 1900 (has links)
Handheld computers may hold the possibility for a one-to-one computer: student ratio. The impact of the use of Palm® (Palm, Inc.) handhelds on information acquisition and use by 5th grade students in a North Texas school during a class research project was investigated. Five research questions were examined using observation, interviews, surveys, and document analysis. Are there differences in information gathering and use with the Palm between gifted, dyslexic, and regular learners? What relevance criteria do students use to evaluate a web site to determine whether to download the site to the Palm and afterwards whether to use the downloaded site's information in the report? How do the Palms affect the writing process? Do the animations and concept maps produced on the Palm demonstrate understanding of the intended concepts? Are there significant differences in results (i.e., final products grade) between Palm users and non-Palm users? Three groups of learners in the class, gifted, dyslexic, and regular learners, participated in the study. The regular and dyslexic students reported using Web sites that had not been downloaded to the Palm. Students reported several factors used to decide whether to download Web sites, but the predominant deciding factor was the amount of information. The students used a combination of writing on paper and the Palm in the preparation of the report. Many students flipped between two programs, FreeWrite and Fling-It, finding information and then writing the facts into the report. The peer review process was more difficult with the Palm. Most students had more grammatical errors in this research report than in previous research projects. By creating animated drawings on the Palm handheld, the students demonstrated their understanding of the invention though sometimes the media or the student's drawing skills limited the quality of the final product. Creating the animations was motivational and addressed different learning styles than a written report alone. No statistically significant difference was found in the scores of the three 6+1 Traits categories, however the Palm users didn't meet the page-length requirement for the research project but the majority of the control class did.
594

An Observational Investigation of On-Duty Critical Care Nurses' Information Behavior in a Nonteaching Community Hospital

McKnight, Michelynn 05 1900 (has links)
Critical care nurses work in an environment rich in informative interactions. Although there have been post hoc self-report survey studies of nurses' information seeking, there have been no observational studies of the patterns and content of their on-duty information behavior. This study used participant observation and in-context interviews to describe 50 hours of the observable information behavior of a representative sample of critical care nurses in a 20-bed critical care hospital unit. The researcher used open, in vivo, and axial coding to develop a grounded theory model of their consistent pattern of multimedia interactions. The resulting Nurse's Patient-Chart Cycle describes nurses' activities during the shift as centering on a regular alternation with the patient and the patient's chart (various record systems), clearly bounded with nursing "report" interactions at the beginning and the end of the shift. The nurses' demeanor markedly changed between interactions with the chart and interactions with the patient. Other informative interactions were observed with other health care workers and the patient's family, friends and visitors. The nurses' information seeking was centered on the patient. They mostly sought information from people, the patient record and other digital systems. They acted on or passed on most of the information they found. Some information they recorded for their personal use during the shift. The researcher observed the nurses using mostly patient specific information, but they also used some social and logistic information. They occasionally sought knowledge based information. Barriers to information acquisition included illegible handwriting, difficult navigation of online systems, equipment failure, unavailable people, social protocols and mistakes caused by multi-tasking people working with multiple complex systems. No formal use was observed of standardized nursing diagnoses, nursing interventions, or nursing outcomes taxonomies. While the nurses expressed respect for evidence-based practice, there clearly was no time or opportunity for reading research literature (either on paper or online) while on duty. All participants expressed frustration with the amount of redundant data entry required of them. The results of this study have significant implications for the design of clinical information systems and library services for working critical care nurses.
595

Identifying Relationships between Scientific Datasets

Alawini, Abdussalam 03 May 2016 (has links)
Scientific datasets associated with a research project can proliferate over time as a result of activities such as sharing datasets among collaborators, extending existing datasets with new measurements, and extracting subsets of data for analysis. As such datasets begin to accumulate, it becomes increasingly difficult for a scientist to keep track of their derivation history, which complicates data sharing, provenance tracking, and scientific reproducibility. Understanding what relationships exist between datasets can help scientists recall their original derivation history. For instance, if dataset A is contained in dataset B, then the connection between A and B could be that A was extended to create B. We present a relationship-identification methodology as a solution to this problem. To examine the feasibility of our approach, we articulated a set of relevant relationships, developed algorithms for efficient discovery of these relationships, and organized these algorithms into a new system called ReConnect to assist scientists in relationship discovery. We also evaluated existing alternative approaches that rely on flagging differences between two spreadsheets and found that they were impractical for many relationship-discovery tasks. Additionally, we conducted a user study, which showed that relationships do occur in real-world spreadsheets, and that ReConnect can improve scientists' ability to detect such relationships between datasets. The promising results of ReConnect's evaluation encouraged us to explore a more automated approach for relationship discovery. In this dissertation, we introduce an automated end-to-end prototype system, ReDiscover, that identifies, from a collection of datasets, the pairs that are most likely related, and the relationship between them. Our experimental results demonstrate the overall effectiveness of ReDiscover in predicting relationships in a scientist's or a small group of researchers' collections of datasets, and the sensitivity of the overall system to the performance of its various components.
596

Informationssökning och källkritik på Internet : En studie om lärares uppfattning av innehållet i läroplanen för årskurs 4-6, om informationssökning och källkritik på Internet samt lärares upplevelser av dessa i undervisningen / Information retrieval and source criticism on the Internet

Gamaleldin, Selma January 2016 (has links)
Inom ämnena svenska och samhällskunskap ska det ske undervisning i informationssökning och källkritik i olika medier i grundskolan. Syftet med denna studie är att bidra med information om hur lärare i årskurs 4-6 uppfattar informationssökning och källkritik i läroplanen samt hur lärare upplever undervisningen i dessa. Enligt den redovisade forskningen i denna studie är källkritik en del av informationssökningen och att lärare anser att elever i årskurs 4-6 inte ska undervisas i informationssökning och källkritik på Internet samt att det finns flera olika sätt för lärare att bedriva sin undervisning. Studien har en kvalitativ fenomenografisk och fenomenologisk forskningsansats. Materialet samlades in genom intervjuer och analyserades genom en kartläggning på likheter och skillnader samt genom att se mönster i lärarnas utsagor. Resultatet visar att lärarna anser att källkritik och informationssökning i undervisningen inte går att särskiljas från varandra, att lärare i årskurs 4-6 bör undervisa elever i informationssökning och källkritik på Internet och att lärare använder sig av diverse olika sätt att bedriva sin undervisning på. / Within the subjects of Swedish and Civics there must be teaching in information retrieval and source criticism in various media in primary school. The purpose of this study is to provide information on how teachers in grades 4-6 perceive information retrieval and source criticism in the primary school curriculum and how teachers experience teaching this subject. According to the research reported in this study the source criticism is part of the information retrieval and that teachers believe that students in grades 4-6 should not be taught information retrieval and source criticism on the Internet, and also that there are several different ways for teachers to pursue their teaching. The study has a qualitative phenomenographic and phenomenological approach. The materials were collected through interviews and was analyzed by mapping the similarities and differences and by finding patterns in the teachers´ descriptions. The results show that teachers believe that the criticism of sources and information retrieval in the teaching can not be distinguished from eachother, that the teachers in grades 4-6 should teach students in information retrieval and source criticism on the Internet and that teachers use various ways to conduct their teaching.
597

Information Seeking in a Virtual Learning Environment

Byron, Suzanne M. 08 1900 (has links)
Duplicating a time series study done by Kuhlthau and associates in 1989, this study examines the applicability of the Information Search Process (ISP) Model in the context of a virtual learning environment. This study confirms that students given an information seeking task in a virtual learning environment do exhibit the stages indicated by the ISP Model. The six-phase ISP Model is shown to be valid for describing the different stages of cognitive, affective, and physical tasks individuals progress through when facing a situation where they must search for information to complete an academic task in a virtual learning environment. The findings in this study further indicate there is no relationship between the amount of computer experience subjects possess and demonstrating the patterns of thoughts, feelings, and actions described by the ISP Model. The study demonstrates the ISP Model to be independent of the original physical library environments where the model was developed. An attempt is made to represent the ISP model in a slightly different manner that provides more of the sense of motion and interaction among the components of thoughts, feelings, and action than is currently provided for in the model. The study suggests that the development of non-self-reporting data collection techniques would be useful in complementing and furthering research to enhance and refine the representation of the ISP Model. Additionally, expanding the research to include the examination of group interaction is called for to enhance the ISP Model and develop further applications that could potentially aid educational delivery in all types of learning environments.
598

Etude de l'ambiguïté des requêtes dans un moteur de recherche spécialisé dans l'actualité : exploitation d'indices contextuels / Study of the ambiguity of queries in a news search engine : exploitation of contextual clues

Lalleman, Fanny 26 November 2013 (has links)
Dans cette thèse, nous envisageons la question de l’ambiguïté des requêtes soumises à un moteur de recherche dans un domaine particulier qui est l’actualité. Nous nous appuyons sur les travaux récents dans le domaine de la recherche d’information (RI) qui ont montré l’apport d’informations contextuelles pour mieux cerner et traiter plus adéquatement le besoin informationnel. Nous faisons ainsi l’hypothèse que les éléments d’information disponibles dans une application de RI (contextes présents dans la base documentaire, répétitions et reformulations de requêtes, dimension diachronique de la recherche) peuvent nous aider à étudier ce problème d’ambiguïté. Nous faisons également l’hypothèse que l’ambiguïté va se manifester dans les résultats ramenés par un moteur de recherche. Dans ce but, nous avons mis en place un dispositif pour étudier l’ambiguïté des requêtes reposant sur une méthode de catégorisation thématique des requêtes, qui s’appuie sur unecatégorisation experte. Nous avons ensuite montré que cette ambiguïté est différente de celle repérée par une ressource encyclopédique telle que Wikipédia. Nous avons évalué ce dispositif de catégorisation en mettant en place deux tests utilisateurs. Enfin, nous fournissons une étude basée sur un faisceau d’indices contextuels afin de saisir le comportement global d’une requête. / In this thesis, we consider the question of the ambiguity of queries submitted to a search engine in a particular area that is news.We build on recent work in the field of information retrieval (IR) that showed the addition of contextual information to better identify and address more adequately the information need. On this basis, we make the hypothesis that the elements of information available in an application of IR (contexts in the collection of documents, repetitions and reformulations of queries, diachronic dimension of the search) can help us to examine this problem of ambiguity. We also postulate that ambiguity will manifest in the results returned by a search engine. In this purpose to evaluate these hypotheses, we set up a device to study the ambiguity of queries based on a method of thematic categorization of queries, which relies on an expert categorization. We then show that this ambiguity is different which is indicated by an encyclopedic resources such as Wikipedia.We evaluate this categorization device by setting up two user tests. Finally, we carry out a study based on a set of contextual clues in order to understand the global behavior of a query.
599

A probabilistic approach for cluster based polyrepresentative information retrieval

Abbasi, Muhammad Kamran January 2015 (has links)
Document clustering in information retrieval (IR) is considered an alternative to rank-based retrieval approaches, because of its potential to support user interactions beyond just typing in queries. Similarly, the Principle of Polyrepresentation (multi-evidence: combining multiple cognitively and/or functionally diff erent information need or information object representations for improving an IR system's performance) is an established approach in cognitive IR with plausible applicability in the domain of information seeking and retrieval. The combination of these two approaches can assimilate their respective individual strengths in order to further improve the performance of IR systems. The main goal of this study is to combine cognitive and cluster-based IR approaches for improving the eff ectiveness of (interactive) information retrieval systems. In order to achieve this goal, polyrepresentative information retrieval strategies for cluster browsing and retrieval have been designed, focusing on the evaluation aspect of such strategies. This thesis addresses the challenge of designing and evaluating an Optimum Clustering Framework (OCF) based model, implementing probabilistic document clustering for interactive IR. Thus, polyrepresentative cluster browsing strategies have been devised. With these strategies a simulated user based method has been adopted for evaluating the polyrepresentative cluster browsing and searching strategies. The proposed approaches are evaluated for information need based polyrepresentative clustering as well as document based polyrepresentation and the combination thereof. For document-based polyrepresentation, the notion of citation context is exploited, which has special applications in scientometrics and bibliometrics for science literature modelling. The information need polyrepresentation, on the other hand, utilizes the various aspects of user information need, which is crucial for enhancing the retrieval performance. Besides describing a probabilistic framework for polyrepresentative document clustering, one of the main fi ndings of this work is that the proposed combination of the Principle of Polyrepresentation with document clustering has the potential of enhancing the user interactions with an IR system, provided that the various representations of information need and information objects are utilized. The thesis also explores interactive IR approaches in the context of polyrepresentative interactive information retrieval when it is combined with document clustering methods. Experiments suggest there is a potential in the proposed cluster-based polyrepresentation approach, since statistically signifi cant improvements were found when comparing the approach to a BM25-based baseline in an ideal scenario. Further marginal improvements were observed when cluster-based re-ranking and cluster-ranking based comparisons were made. The performance of the approach depends on the underlying information object and information need representations used, which confi rms fi ndings of previous studies where the Principle of Polyrepresentation was applied in diff erent ways.
600

Enhancing recall and precision of web search using genetic algorithm

Al-Dallal, Ammar Sami January 2012 (has links)
Due to rapid growth of the number of Web pages, web users encounter two main problems, namely: many of the retrieved documents are not related to the user query which is called low precision, and many of relevant documents have not been retrieved yet which is called low recall. Information Retrieval (IR) is an essential and useful technique for Web search; thus, different approaches and techniques are developed. Because of its parallel mechanism with high-dimensional space, Genetic Algorithm (GA) has been adopted to solve many of optimization problems where IR is one of them. This thesis proposes searching model which is based on GA to retrieve HTML documents. This model is called IR Using GA or IRUGA. It is composed of two main units. The first unit is the document indexing unit to index the HTML documents. The second unit is the GA mechanism which applies selection, crossover, and mutation operators to produce the final result, while specially designed fitness function is applied to evaluate the documents. The performance of IRUGA is investigated using the speed of convergence of the retrieval process, precision at rank N, recall at rank N, and precision at recall N. In addition, the proposed fitness function is compared experimentally with Okapi-BM25 function and Bayesian inference network model function. Moreover, IRUGA is compared with traditional IR using the same fitness function to examine the performance in terms of time required by each technique to retrieve the documents. The new techniques developed for document representation, the GA operators and the fitness function managed to achieves an improvement over 90% for the recall and precision measures. And the relevance of the retrieved document is much higher than that retrieved by the other models. Moreover, a massive comparison of techniques applied to GA operators is performed by highlighting the strengths and weaknesses of each existing technique of GA operators. Overall, IRUGA is a promising technique in Web search domain that provides a high quality search results in terms of recall and precision.

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