1,721,007 research outputs found
Un Metodo per la Misura del Fattore di Accoppiamento Elettromeccanico dei Materiali Piezoelettrici
No full textUna Nuova Metodologia per l'Individuazione e la Decodifica del Codice a Barre in una Scena Bidimensionale
No full textElectrical impedance mismatch in capacitive micromachined ultrasonic transducers
No full textSeveral investigations on the electrical impedance mismatch, the insertion loss and the noise performance of capacitive micromachined ultrasonic transducers (cMUTs) are reported. The theoretical analysis applies the concepts of radio communication circuits to the analytical modeling of a two-way system made of a transmitting cMUT and a receiving one. Since the simulation results can emphasize the effects of either the transmitting and receiving electronics or the characteristics of the transducers on the performance of the system, the proposed approach is very useful for the purpose of optimization. For example, a selection between receivers can be easily done as a trade-off between the insertion loss and the noise sensitivity of the syste
3D Ultrasound palm vein pattern for biometric recognition
No full textIn this work, an ultrasound technique for achieving 3D palm vein patterns for biometric recognition purposes is proposed and experimentally tested. Commercial ultrasound
imaging machine and linear arrays have been employed. Both imaging and power Doppler analysis have been performed to detect veins. The probe is moved in the directional orthogonal to the array by an automated scanning system and at each step a 2D frame is captured and stored to form a 3D matrix.
The data from the 3D matrix are elaborated for achieving 3D ultrasonic vein patterns. The proposed technique has been applied to acquire hand vein patterns of about a dozen of distinct volunteers, which are opportunely rendered and discussed
A Flexible Piezoelectric Motor Based on an Acoustic Fiber for Echographic Endoscopic Probes
No full text
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
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