1,720,954 research outputs found

    Inter-cell interference coordination in 5G ultra-dense networks

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    The exponentially increasing demand for mobile broadband communications has led to the dense deployment of cellular networks with aggressive frequency reuse patterns. The future Fifth Generation (5G) networks are expected to overcome capacity and throughput challenges by adopting a multi-tier architecture where several low-power Base Stations (BSs) are deployed within the coverage area of the macro cell. Hence, Inter-Cell Interference (ICI) caused by the simultaneous usage of the same spectrum in different cells creates severe problems. ICI reduces system throughput and network capacity, and has a negative impact on cell-edge users and overall system performance. Therefore, effective interference coordination techniques are required, especially, for user-to-cell association and resource allocation to mitigate severe impact of ICI on system performance in 5G heterogeneous networks (HetNets). This is to improve Quality of Service (QoS) and maximize system throughput arising from the deployment of small cell overlay on macro BSs in heterogeneous cellular networks, which creates traffic load imbalance due to varying transmit power of different BSs in the downlink. In this research, a cell association scheme based on Cell Range Expansion (CRE), integrated with power control techniques is proposed. Simulation results are presented to show the ability of this technique to protect offloaded users from severe ICI and maximize throughput while achieving desirable QoS and load balancing for users of different tiers. With the advancement of information and computer technology, the envisioned 5G wireless communication is expected to encompass an unprecedented heterogeneous and ultra-dense communication environment. Vehicular communications play a vital role in 5G wireless network and have been widely studied recently due to its great potential to ensure reliability and support intelligent transportation and various safety applications. This research therefore exploits the tractability of stochastic geometry to analyze the coverage of urban vehicular networks, by deriving a closed-form expression to maximize the ergodic capacity of cellular users (CUEs) and mitigate interference, taking into consideration the QoS requirements of both vehicle-to-vehicle (V2V) and vehicleto-infrastructure (V2I) links. Consequently, the latency and reliability requirements of V2V/V2I links are formulated as optimization constraints, involving joint power allocation and spectrum sharing (PASS), taking into account the slow varying and large scale channel state information (CSI) measurements. Due to non-convex nature of the problem, the optimization is transformed into sub-optimal convex equivalence, while a low complexity Algorithm that yields optimal resource allocation is then designed to solve it. Simulation results are used to show enhanced performance in our approach compared to related works. Finally, the upsurge in the number of connected devices, such as smart cars, to the envisioned 5G technology is expected to pose high capacity and data rate demands on the network. The conventional access techniques (i.e., CDMA, TDMA and OFDMA) may not meet stringent requirements, such as ultra-low latency, high reliability, improved spectral efficiency and massive device connectivity. This work further investigates non-orthogonal multiple access (NOMA) technique as promising solution to improve spectral efficiency and reduce interference in 5G Ultra Dense Network (UDN). The NOMA scheme is combined with two promising capacity and bandwidth enhancement techniques - massive multiple input and multiple output (MIMO) and carrier aggregation (CA), for overall network performance. In particular, for the proposed novel NOMA-CA approach, we justify the importance of maintaining green communication as a key requirement for 5G with Energy Efficiency (EE) analysis. Firstly, a proportional fairness scheduler is used to perform resource allocation and maintain fairness among users based on their channel condition. Secondly, an optimization problem to maximize the EE weighted-sum under joint power and bandwidth allocation on each aggregated component carrier (CC) is formulated. Conventionally, the formulated optimization is transformed from non-convex to convex problem. An iteratively adaptive Algorithm is then developed to find optimal solution for the problem. Simulation results show better improvement in EE and sum rate compared to the traditional OMA scheme

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Variations on the Author

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    “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

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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

    Author Under Sail The Imagination of Jack London, 1893-1902

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    In Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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