1,720,960 research outputs found
Client Based Arbitration for Multiplexed Multimedia Streams
No full textThe quality of multimedia' applications depends primarily on how the different media are compressed, packetised, and transported over a network. Compression algorithms reduce the amount of data to be transmitted by removing redundancy in the media. Most of these algorithms are lossy, and can significantly degrade the media quality. Furt~ermore, degradations occur when packets are transported over lossy and unreliable networks such as the Internet. Due to the heterogeneous nature of multimedia traffic, complex interactions occur when they are transported over the same medium. This is true in packetswitched networks such as the Internet, where packet delivery is not guaranteed. Each traffic requires different treatment from the network transport services, which can have direct impact on other traffic.This thesis presents an evaluation of how multimedia traffic affect one another when transported over the same medium, for various network conditions. Evaluation is performed using video, audio and still images over a synthesised platform/system developed for this purpose. A traffic generator, which generates traffic from real video sequences, has also been developed. The platform and the traffic generator serve as a novel tool for simulating any number and type of traffic, for evaluation of multimedia traffic interactions.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A Model for Mapping Combined Effects of Quality of Service Parameters and Device Features on Video Streaming Quality of Experience
Get PDFMaintaining quality of streaming video is challenged by network faults resulting into freezes and rebufferings on the video. On top of the network effects, device features have impacts on the image of the video frames displayed during streaming. Despite the simultaneous impacts of video quality from network and device, previous studies considered individual impact of network parameters or devices as influencing factors to propose Quality of Experience (QoE) models. This study proposed QoE model by mapping combined effects from both network and device on video streamed QoE. An experiment to study the effects of video quality from combined effects of network and device over the wireless involved 35 subjects. Combination of packet loss, packet reordering, and delay were emulated using network emulator following Design of Experiment methodology. Through analysis of variance, the study found that packet loss had the highest impact, followed by device features, reordering, and delay on the video QoE. From the combined effects, two-way interactions and three-way interactions had significant effects on the video QoE. Through additive and linearity behavior of the input factors from network and device on video streaming QoE, a multi-factor model was derived.
Keywords: Design of Experiment (DOE); Mean Opinion Score (MOS); Quality of Experience (QoE); Quality of Service (QoS); Video Quality Assessmen
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Determinants of Software-as-a-Service Adoption by Small and Medium Enterprises in Tanzania
Get PDFOrganizations in developed economies use the software-as-a-service (SaaS) model to improve performance and efficiency. However, its adoption in developing economies such as Tanzania is very low due to limited research on its adoption. This study enhances the adoption of SaaS in Tanzanian small and medium enterprises (SMEs) by proposing a conceptual framework based on the diffusion of innovation theory and the technology-organization-environment framework and recommending strategies for improving adoption. The framework was tested using regression analysis on data collected from 139 SMEs. Findings show that eight factors, relative advantage, compatibility, awareness, cost, perceived security and privacy risk, reliability and availability, top management support and trading partners’ pressure, significantly affect adoption of SaaS by SMEs in Tanzania. The study recommends that cloud service providers address security challenges and software compatibility issues and ensure SaaS systems are available, and SMEs’ top management provide support in implementing SaaS solutions to enhance their adoption
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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