1,721,053 research outputs found
Composite right/left handed based 3-port broadband differential phase shifter
No full textStarting from the common 4-port configuration of CRLH (Composite Right/Left Handed) based Differential Phase Shifter (DPS), by connecting the two input ports, a 3-port configuration is proposed. Both DPS topologies are analyzed by means of an analytical approach and design procedure is proposed. The 3-port DPS has a convenient topology for application such as antenna phased array feeding circuits. It is shown that the frequency bandwidth of this DPS may be maximized if a transmission line, having an optimum length, is inserted before the CRLH structure. A possible layout for 3-port topology consisting of transmission lines and chip capacitors and inductors is designed and electromagnetic analysis is performed
A novel approach for the synthesis of composite right/left-handed circuits
No full textA semi-lumped Composite Right/Left-Handed (CRLH) equivalent circuit is proposed and analysed, then a CRLH design method is presented. This equivalent circuit use a transmission line which replace the inductance of the series resonator from the fully lumped CRLH equivalent circuit, but also contains a parallel lumped resonator. A CRLH structure is designed following the proposed method and then it is analysed numerically. It is shown the results are in very good agreement with the expected ones
Second harmonic generation on non-linear composite right-/left-handed transmission line
No full textThe second harmonic generation along the CRLH (Composite Right/Left-Handed) NLTLs (Non-Linear Transmission Lines) is analytically and numerically analysed. The nonlinearity of the structure is introduced by series connected Schottky-varactor diodes. The results show the possibility to use CRLH NLTL as broadband frequency doubler having high efficiency conversion for low number of diodes
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
Smoothing and surface planarization of sacrificial layers in MEMS technology
No full textIn this work we present a novel technology for tailoring the edges of a polymer sacrificial layer by combining multiple techniques. Standard polymers like Shipley Microposit S1818 for the sacrificial layers and gold as a structural layer have been used for our purposes. As a result, oblique profiles of double clamped bridges have been obtained, characterized by an improved homogeneity of the deposited metal thickness on the edges and by a very good surface planarity
Design and fabrication of mmic coupled lines coupler consisting of composite right/left-handed transmission lines
No full textCoupled-line directional coupler based on CRLH (Composite Right/Left-Handed) cascaded structures is designed, analyzed and then fabricated. The technological realization of the coupler involves one mask process on silicon substrate, using CPWs (CoPlanar Waveguides). The preliminary measurements were also performed, showing that the experimental results fit well the simulation results
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