1,721,432 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
Lithium niobate electro-optic sensor for examining conductive patterns on display panels
No full textThe fabrication of an electric field detector using an electro-optic LiNbO3 (LN) single crystal is studied for an application to check the electric field of a conductively patterned panel. When this electric field detector moves on the surface of the panel, a constant air gap, which is close enough for the given field intensity and resolution, must be maintained so as not to damage the surface patterns. For the effective detection of electric field change in this air gap state, an LN single crystal is selected because of its relatively high electro-optic coefficient, transmittance, and low dielectric constant. X-cut LN and Z-cut LN structures are selected to estimate the applicability of LN,by simulation on the optical intensity variation and electric field distribution of various structures. At an air gap of 10 mum in the Z-cut LN structure, V-pi is about 100 to 150 V and optical intensity variation with unit voltage (Q) is 6.7%/V larger than that of the X-cut LN structure. From these characteristics, the Z-cut LN structure proves to be applicable for the electric field detector because the variation of optical intensity (0.8 muW) is sufficient in the ac driving voltage region (+/-20 V) of a real system. (C) 2003 Society of Photo-Optical Instrumentation Engineers
Fabrication of PZT thick films on silicon substrates for piezoelectric actuator
No full textIn recent years, there has been an increased interest in ferroelectric lead zirconate titanate (PZT) films for applications in piezoelectric devices. Many potential applications require a film thickness of about 10 mu m for higher force, better sensitivity and stability. In this study we fabricate lead zirconate titanate (PZT) thick films by screen printing on silicon substrates with a platinum bottom electrode. Various substrates were studied. The longitudinal piezoelectric coefficient, d(33), was measured by the normal load testing method. Breakdown voltage, tan delta, P-E hysteresis loop and permittivity were measured on the PZT thick films. The results are promising for the use of PZT thick films in various applications, for example, in silicon micromachined micro-pump.Ministry of Science and
Technology (MOST), Ministry of Commerce,
Industry and Energy (MOCIE) and Samsung
Electronics In
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
Modeling of Electrochemical Performance and its Relation to Mechanical Responses of Li Metal Batteries
No full textThe development and commercialization of Li metal batteries are hindered by safety challenges. Accordingly, significant efforts have been made to improve the stability of Li anodes. However, only a few studies have focused on the impact of mechanical deformation caused by Li deposition at the cell level. The strain changes are considerably large and should be further investigated for their mechanical impact. Therefore, in this study, we focused on the development of a physics-based model for Li metal batteries. To the best of our knowledge, this is the first attempt to develop a model that can describe the electrochemical and mechanical responses of a full Li metal cell with different material properties, external pressures, and boundary conditions. The Young's modulus and higher expansion ratio of the negative electrode increase overall stress generation. However, overall cell pressure decreases with an increasing expansion ratio of the positive electrode. This is because the positive electrode contracts in response to the significant expansion of the lithium metal. The current model provides insights into the mechanisms by which these factors affect the electrochemical and mechanical behaviors of Li metal cells. This model provides guidance for battery design and management of Li metal cells.
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
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
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