1,720,990 research outputs found
Is five too many? Simulation analysis of profitability and cost structure in the Korean mobile telephone industry
No full textFour new nationwide entrants were introduced into the Korean mobile telephone industry provoking intense competition among the five carriers by late 1997. Some assert that there is excessive competition and industry restructuring is needed. In this paper, we analyze the profitability of mobile telephone carriers and the degree to which cost is reduced through M&A, thereby obtaining principal information on the economic incentives for industry restructuring. (C) 2001 Elsevier Science Ltd. All rights reserved
Numerical Study on Modulation Efficiency Enhancement of SIS Optical Phase Shifter Using Negative Capacitance Effect
No full textStructural and optical properties of In0.5Ga0.5As/GaAs quantum dots in an In0.1Ga0.9As well using repeated depositions of InAs/GaAs short-period superlattices for the application of optical communication
No full textWe report structural and optical properties of In0.5Ga0.5As/GaAs quantum dots (QDs) in a 100 angstrom-thick In0.1Ga0.9As well grown by repeated depositions of InAs/GaAs short-period superlattices with atomic force microscope, transmission electron microscope (TEM) and photoluminescence (PL) measurement. The QDs in an InGaAs well grown at 510 degrees C were studied as a function of n repeated deposition of 1 monolayer thick InAs and 1 monolayer thick GaAs for n = 5 - 10. The heights, widths and densities of dots are in the range of 6-22.0nm, 40-85nm, and 1.6-1.1 x 10(10)/cm(2), respectively, as n changes from 5 to 10 with strong alignment along [1-10] direction. Flat and pan-cake-like shape of the QDs in a well is found in TEM images. The bottoms of the QDs are located lower than the center of the InGaAs well. This reveals that there was intermixing-interdiffusion-of group III materials between the InGaAs QD and the InGaAs well during growth. All reported dots show strong 300 K-PL spectrum, and 1.276 mu m (FWHM: 32.3 meV) of 300 K-PL peak was obtained in case of 7 periods of the QDs in a well, which is useful for the application to optical communications. (c) 2006 Elsevier B.V. All rights reserved
Monolithic integration of GaAs//InGaAs photodetectors for multicolor detection
No full textMulticolor photodetectors (PDs) by using bulk p-i-n based visible GaAs and near-infrared (IR) InGaAs PD have been successfully fabricated via monolithic integration by wafer bonding and epitaxial lift-off. It showed high-performance individual operation comparable to that of bulk PDs with tight vertical alignment on a single substrate for future high-resolution multicolor PDs. At the same time, it covered a broad wavelength range from visible to IR
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
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
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