1,720,983 research outputs found
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
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
Low cost and conformal microwave water-cut sensor for optimizing oil production process
No full textEfficient oil production and refining processes require the precise measurement of water content in oil (i.e., water-cut) which is extracted out of a production well as a byproduct. Traditional water-cut (WC) laboratory measurements are precise, but are incapable of providing real-time information, while recently reported in-line WC sensors (both in research and industry) are usually incapable of sensing the full WC range (0 – 100 %), are bulky, expensive and non-scalable for the variety of pipe sizes used in the oil industry.
This work presents a novel implementation of a planar microwave T-resonator for fully non-intrusive in situ WC sensing over the full range of operation, i.e., 0 – 100 %. As opposed to non-planar resonators, the choice of a planar resonator has enabled its direct implementation on the pipe surface using low cost fabrication methods. WC sensors make use of series resonance introduced by a λ/4 open shunt stub placed in the middle of a microstrip line. The detection mechanism is based on the measurement of the T-resonator’s resonance frequency, which varies with the relative percentage of oil and water (due to the difference in their dielectric properties). In order to implement the planar T-resonator based sensor on the curved surface of the pipe, a novel approach of utilizing two ground planes is proposed in this work. The innovative use of dual ground planes makes this sensor scalable to a wide range of pipe sizes present in the oil industry. The design and optimization of this sensor was performed in an electromagnetic Finite Element Method (FEM) solver, i.e., High Frequency Structural Simulator (HFSS) and the dielectric properties of oil, water and their emulsions of different WCs used in the simulation model were measured using a SPEAG-dielectric assessment kit (DAK-12). The simulation results were validated through characterization of fabricated prototypes. Initial rapid prototyping was completed using copper tape, after which a novel reusable 3D-printed mask based fabrication was also successfully implemented, which would resemble screen printing if it were to be implemented in 3D.
In order to verify the design’s applicability for the actual scenario of oil wells, where an oil/water mixture is flowing through the pipes, a basic flow loop was constructed in the IMPACT laboratory at KAUST. The dynamic measurements in the flow loop showed that the WC sensor design is also equally applicable for flowing mixtures. The proposed design is capable of sensing the WC with a fine resolution due to its wide sensing range, in the 80 – 190 MHz frequency band. The experimental results for these low cost and conformal WC sensors are promising, and further characterization and optimization of these sensors according to oil field conditions will enable their widespread use in the oil industry
Additively Manufactured Conformal Microwave Sensors for Applications in Oil Industry
No full textDepleting oil reserves and fluctuating oil prices have necessitated to increase the efficiency of oil production process. This thesis is focused on developing low-cost sensors, which can increase oil production efficiency through real-time monitoring of oil wells and help in safe transport of oil products from the wells to the refineries. Produced fluid from an oil well is a complex mixture of oil, water and gases, which needs to be quantified for various strategic and operational decisions. For many years, test separators have been used to separate oil, water and gases into three separate streams and then to analyse them individually. However, test separators are being replaced by multiphase flow meters (MPFM) which can analyse the complex mixture of oil, water and gas without separating it. However, existing MPFMs are either intrusive or require fluid mixing before the sensing stage. In contrast to existing techniques, first part of this thesis presents a microwave sensor, which can measure water fraction in oil in a non-intrusive way without requiring it to be mixed. Gas fraction sensing can also be performed using the same microwave sensor, which is an on-going work. The sensor operates on dielectric measurement principles and comprises a microstrip T-resonator that has been optimized for a 3D pipe surface. Certain locations on an oil field have limited available space, for which we have also presented a compact version of the microwave water-fraction sensor in this thesis. In this version, metallic housing of the sensor has been used to function as a ground plane for the coaxially located spiral resonator. This housing also protects the sensor from environmental effects. In addition to the efficient production of oil, its safe transport is also a concern for the industry. It is physically impossible to inspect a network of thousands of kilometres of pipelines manually. The existing leak detectors suffer from low sensitivity, high false alarms and dependence on environmental effects. In the last part of this thesis, we present a flexible ringresonator based leak detector, which can be clamped at vulnerable locations along the pipeline for early leak detection
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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