1,720,983 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
A Framework for the Performance Analysis and Simulation of RF-Mesh Advanced Metering Infrastructures for Smart Grid Applications
Full text linkRÉSUMÉ: L'Infrastructure de Mesurage Avancée (IMA), conçue à l'origine pour lire à distance des compteurs intelligents, est actuellement considérée comme une composante essentielle dans le domaine des Smart Grid. Le but principal des IMAs est de connecter le grand nombre de compteurs intelligents installés chez les clients au le centre de contrôle de données de l'entreprise d'électricité et viceversa. Cette communication bidirectionnelle est une caractéristique recherchée par un grand nombre d'applications, qui visent à utiliser ces infrastructures comme support à la transmission de leurs données dans le réseau électrique, comme par exemple la gestion de la charge et la demande-réponse. Un grand nombre de technologies et de protocoles de communication sont actuellement utilisés dans les IMAs : parmi les solutions disponibles, le RF-Mesh est une des plus populaires, surtout grâce au bas coût pour l'installation et les équipements. Toutefois, le débit nominal des communications RF-Mesh est très bas, de l'ordre des dizaines de kbps, et la littérature qui traite leur performance est très limitée. Ceci pourrait en limiter l'utilisation pour des applications autres que la lecture à distance des compteurs intelligents. Ce travail de thèse vise à développer un système de modèles et outils pour évaluer la performance des réseaux RF-Mesh et encourager leur utilisation pour un grand nombre d'applications dans le domaine des Smart Grid. Le système d'évaluation de performance proposé est constitué (i) de modèles analytiques, pour calculer la probabilité de collision entre les paquets transmis, (ii) d'un simulateur de réseau, pour recréer le fonctionnement des réseaux RF-Mesh dans un environnement virtuel, (iii) d'un générateur de topologie, pour créer des cas réalistes en se basant sur des données géographiques et (iv) des méthodes pour l'analyse de la performance. Trois différents modèles analytiques ont été implémentés. Dans les deux premiers, une nouvelle formule analytique a été utilisée pour calculer la probabilité de collision entre paquets. La probabilité de collision est ensuite utilisée pour estimer le délai moyen de/vers chaque compteur intelligent dans l'IMA analysée. Par la suite, des indices de performance, basés sur le délai moyen, sont utilisés pour faire des analyses de performance : études de faisabilité pour les applications de Smart Grid, l'identification de noeuds critiques et d'éventuels goulots d'étranglement. Dans le troisième modèle analytique, la théorie de Markov-Modulated System est utilisée pour prendre en considération d'importants détails d'implémentation, comme la probabilité de retransmission et la taille des mémoires tampons des noeuds, qui n'avaient pas été inclus dans la modélisations précédente. ABSTRACT: Advanced Metering Infrastructure (AMI), originally conceived to replace the old Automated Meter Reading (AMR) infrastructures, have now become a key element in the Smart Grid context and might be used for applications other than remote meter reading. The main driver to their widespread installation is that they provide power utilities with a bidirectional connectivity with the smart meters. A wide variety of communication networks are currently proposed to support the implementation of AMIs, and, among them, the RF-Mesh technology seems to be very popular. The main reasons for its adoption are the proprietary infrastructure and the modest cost for the installation and the equipment. However, RF-Mesh systems are characterized by poor achievable data-rates in the order of 10 kbps, and their performance is not well studied in the literature. The lack of tools and methods for the performance evaluation might be a roadblock to their widespread adoption. This thesis aims at filling this gap and increase the knowledge of large-scale RF-Mesh systems to foster their use for a wide variety of applications. We propose a comprehensive framework for the performance evaluation of large-scale AMIs adopting the RF-Mesh technology. The framework includes (i) a geo-based topology generator that uses geographic data to produce realistic AMI cases, (ii) analytic models for the computation of packet collision probability and delay, (iii) a network simulator to recreate the behavior of large-scale RF-Mesh systems, and (iv) methods to evaluate the performance. Three different analytic models are included in the framework. The first two provide a novel analytic formulation of the packet collision probability in a mesh network with timeslotted ALOHA and the Frequency Hopping Spread Spectrum (FHSS) protocol : the collision probability is then used to estimate the average delay in the network, and to define and evaluate performance indexes (e.g., critical nodes and survival function). In the third model, a complex Markov-Modulated System (MMS) is used to take into consideration important implementation details, such as the retransmission probability and the buffer size, that were not considered in the two previous models. This model also provides a more accurate computation of the packet collision probability. A Poisson distribution is used to represent the traffic coming from potential Smart Grid applications. The framework also includes an RFMesh network simulator, written in Java and Python. The tool provides additional enhanced features with respect to the analytic models, such as a dynamic routing protocol or different traffic distributions
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Energy savings in wireless mesh networks in a time variable context
Full text linkLAUREA SPECIALISTICAIl consumo energetico nelle reti di Telecomunicazioni sta diventando un problema
di enorme rilevanza nello scenario globale e, tra tutti i settori, quello dell’accesso - ed
in particolar modo la parte senza fili - é responsabile della maggior parte della spesa
di energia elettrica. Le reti wireless stanno incrementando la loro diffusione anche
nell’infrastruttura dorsale dei sistemi cellulari a causa principalmente dei bassi costi
e della facilitá di sviluppo. In questo contesto le Wireless Mesh Networks (WMN)
sono considerate tra le risorse piú idonee per la loro versatilitá che permette configurazioni
flessibili. In questo lavoro di tesi noi combiniamo la flessibilitá delle
WMN con l’esigenza di riduzione dei consumi energetici presentando un modello
d’ottimizzazione per la gestione delle reti che prende in considerazione il compromesso
tra i requisiti energetici e la variazione della domanda. Sono presentati inoltre
l’approccio usato per la risoluzione e una profonda discussione sulla gestione del consumo
energetico nelle reti WMN.Energy consumption of communication systems is becoming a fundamental issue
and, among all the sectors, wireless access networks are largely responsible for
the increase in consumption. In addition to the access segment, wireless technologies
are also gaining popularity for the backhaul infrastructure of cellular systems
mainly due to their cost and easy deployment. In this context, Wireless Mesh Networks
(WMN) are commonly considered the most suitable architecture because of
their versatility that allows flexible configurations. In this thesis we combine the
flexibility of WMN with the need for energy consumption reduction by presenting
an optimization framework for network management that takes into account the
trade off between the network energy needs and the daily variations of the demand.
A resolution approach and a thorough discussion on the details related to WMN
energy management are also presented
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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