51 research outputs found

    A Behavioral Perspective on Transmuting Successive Multi-session Web Searches

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    Multi-session successive information searches are common and could have great implications for effective Web site design. This paper intends to enhance the understanding of successive information searches by observing how the behavioral characteristics of the searchers evolve over sessions. It focuses on a specific type of successive searches called transmuting successive searches, where the searchers learn about and gradually refine their information problems along the course of information searches. The results show that the searchers’ behavioral characteristics indeed exhibit different patterns in different sessions. The results also help validate a theoretical model in explaining successive searches and help revise system requirements for supporting the concerned search behavior

    Investigating User Search Tactic Patterns and System Support in Using Digital Libraries

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    This study aims to investigate users\u27 search tactic application and system support in using digital libraries. A user study was conducted with sixty digital library users. The study was designed to answer three research questions: 1) How do users engage in a search process by applying different types of search tactics while conducting different search tasks?; 2) How does the system support users to apply different types of search tactics?; 3) How do users\u27 search tactic application and system support for different types of search tactics affect search outputs? Sixty student subjects were recruited from different disciplines in a state research university. Multiple methods were employed to collect data, including questionnaires, transaction logs and think-aloud protocols. Subjects were asked to conduct three different types of search tasks, namely, known-item search, specific information search and exploratory search, using Library of Congress Digital Libraries. To explore users\u27 search tactic patterns (RQ1), quantitative analysis was conducted, including descriptive statistics, kernel regression, transition analysis, and clustering analysis. Types of system support were explored by analyzing system features for search tactic application. In addition, users\u27 perceived system support, difficulty, and satisfaction with search tactic application were measured using post-search questionnaires (RQ2). Finally, the study examined the causal relationships between search process and search outputs (RQ 3) based on multiple regression and structural equation modeling. This study uncovers unique behavior of users\u27 search tactic application and corresponding system support in the context of digital libraries. First, search tactic selections, changes, and transitions were explored in different task situations - known-item search, specific information search, and exploratory search. Search tactic application patterns differed by task type. In known-item search tasks, users preferred to apply search query creation and following search result evaluation tactics, but less query reformulation or iterative tactic loops were observed. In specific information search tasks, iterative search result evaluation strategies were dominantly used. In exploratory tasks, browsing tactics were frequently selected as well as search result evaluation tactics. Second, this study identified different types of system support for search tactic application. System support, difficulty, and satisfaction were measure in terms of search tactic application focusing on search process. Users perceived relatively high system support for accessing and browsing tactics while less support for query reformulation and item evaluation tactics. Third, the effects of search tactic selections and system support on search outputs were examined based on multiple regression. In known-item searches, frequencies of query creation and accessing forwarding tactics would positively affect search efficiency. In specific information searches, time spent on applying search result evaluation tactics would have a positive impact on success rate. In exploratory searches, browsing tactics turned out to be positively associated with aspectual recall and satisfaction with search results. Based on the findings, the author discussed unique patterns of users\u27 search tactic application as well as system design implications in digital library environments

    Quality aspects of Internet telephony

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    Internet telephony has had a tremendous impact on how people communicate. Many now maintain contact using some form of Internet telephony. Therefore the motivation for this work has been to address the quality aspects of real-world Internet telephony for both fixed and wireless telecommunication. The focus has been on the quality aspects of voice communication, since poor quality leads often to user dissatisfaction. The scope of the work has been broad in order to address the main factors within IP-based voice communication. The first four chapters of this dissertation constitute the background material. The first chapter outlines where Internet telephony is deployed today. It also motivates the topics and techniques used in this research. The second chapter provides the background on Internet telephony including signalling, speech coding and voice Internetworking. The third chapter focuses solely on quality measures for packetised voice systems and finally the fourth chapter is devoted to the history of voice research. The appendix of this dissertation constitutes the research contributions. It includes an examination of the access network, focusing on how calls are multiplexed in wired and wireless systems. Subsequently in the wireless case, we consider how to handover calls from 802.11 networks to the cellular infrastructure. We then consider the Internet backbone where most of our work is devoted to measurements specifically for Internet telephony. The applications of these measurements have been estimating telephony arrival processes, measuring call quality, and quantifying the trend in Internet telephony quality over several years. We also consider the end systems, since they are responsible for reconstructing a voice stream given loss and delay constraints. Finally we estimate voice quality using the ITU proposal PESQ and the packet loss process. The main contribution of this work is a systematic examination of Internet telephony. We describe several methods to enable adaptable solutions for maintaining consistent voice quality. We have also found that relatively small technical changes can lead to substantial user quality improvements. A second contribution of this work is a suite of software tools designed to ascertain voice quality in IP networks. Some of these tools are in use within commercial systems today

    Access to Knowledge in India

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    This book is available as open access through the Bloomsbury Open Access programme and is available on www.bloomsburycollections.com. This is the third volume in our Access to Knowledge series. India is a $1 trillion economy which nevertheless struggles with a very high poverty rate and very low access to knowledge for almost seventy percent of its population which lives in rural areas. This volume features four parts on current issues facing intellectual property, development policy (especially rural development policy) and associated innovation, from the Indian perspective. Each chapter is authored by scholars taking an interdisciplinary approach and affiliated to Indian or American universities and Indian think-tanks. Each examines a policy area that significantly impacts access to knowledge. These include information and communications technology for development; the Indian digital divide; networking rural areas; copyright and comparative business models in music; free and open source software; patent reform and access to medicines; the role of the Indian government in promoting access to knowledge internationally and domestically

    Advances in Intelligent Vehicle Control

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    This book is a printed edition of the Special Issue Advances in Intelligent Vehicle Control that was published in the journal Sensors. It presents a collection of eleven papers that covers a range of topics, such as the development of intelligent control algorithms for active safety systems, smart sensors, and intelligent and efficient driving. The contributions presented in these papers can serve as useful tools for researchers who are interested in new vehicle technology and in the improvement of vehicle control systems

    2005- 2008 UNLV McNair Journal

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    Journal articles based on research conducted by undergraduate students in the McNair Scholars Program Table of Contents Biography of Dr. Ronald E. McNair Statements: Dr. Neal J. Smatresk, UNLV President Dr. Juanita P. Fain, Vice President of Student Affairs Dr. William W. Sullivan, Associate Vice President for Retention and Outreach Mr. Keith Rogers, Deputy Executive Director of the Center for Academic Enrichment and Outreach McNair Scholars Institute Staf

    Access to Knowledge in India

    Get PDF
    This book is available as open access through the Bloomsbury Open Access programme and is available on www.bloomsburycollections.com. This is the third volume in our Access to Knowledge series. India is a $1 trillion economy which nevertheless struggles with a very high poverty rate and very low access to knowledge for almost seventy percent of its population which lives in rural areas. This volume features four parts on current issues facing intellectual property, development policy (especially rural development policy) and associated innovation, from the Indian perspective. Each chapter is authored by scholars taking an interdisciplinary approach and affiliated to Indian or American universities and Indian think-tanks. Each examines a policy area that significantly impacts access to knowledge. These include information and communications technology for development; the Indian digital divide; networking rural areas; copyright and comparative business models in music; free and open source software; patent reform and access to medicines; the role of the Indian government in promoting access to knowledge internationally and domestically
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