1,720,967 research outputs found
A portable analyzer for vocal signal monitoring
No full textA prototype of portable vocal analyzer is proposed in this paper that is conceived to estimate the parameters that allow voice disorders to be identified. The basic architecture of the vocal analyzer is described, which is based on a sensor that is worn by the person under monitoring. Two alternative sensors are investigated: an accelerometer and an Electret Condenser Microphone (ECM). While the former would be characterized by a low sensitivity with respect to air-borne effects, the latter would provide a larger bandwidth, thus allowing parameters related to the vowel quality to be estimated. Particular attention will be paid towards traceability assurance and uncertainty estimation and a calibration procedure for each of the estimated parameters will be proposed. Preliminary results are here reported that refer to the estimation of the parameters Sound Pressure Level (SPL) and fundamental frequency (F0) through the accelerometer and ECM based measuring chain
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
Optical fiber sensors for long- and short-term crack monitoring
No full textThis paper describes a fiber displacement sensor and analyzes its performance in evaluating the evolution of cracks for structural health monitoring applications, both over short and long time periods. The sensor is based on plastic optical fibers, a choice that allows having all the advantages typical of optical fibers, but with costs comparable to the more common electro-mechanical systems. Two sensor topologies have been realized and some experimental results about laboratory and in field tests are reported to assess the effectiveness of the proposed solutio
An Intensity Based Fiber Accelerometer
No full textThe paper presents a low cost, compact, fiber optic sensor for measuring acceleration in environmentally harsh industrial applications. The sensor is based on the deformation of a cantilever measured through the variation of the propagation loss of a plastic optical fiber fixed on its surface. In order to enhance the sensitivity to bending, the fiber surface has been modified with grooves extending to part of the core. Preliminary experimental results have confirmed the feasibility of the proposed approach and the possibility to use the sensor both as an accelerometer and as a seismomete
Caratterizzazione spettroscopica di fibre ottiche per la realizzazione di laser di media e alta potenza
No full textIl lavoro presentato riguarda la realizzazione di un banco di misura per la caratterizzazione di fibre ottiche drogate con ioni di terre rare, che trovano applicazione nella realizzazione di laser e amplificatori in fibra ottica di media e alta potenza (decine-centinaia di W). Il banco è composto da un monocromatore in grado di separare le componenti spettrali di un generico segnale ottico applicato al suo ingresso e di indirizzarle verso un sistema di rivelazione/visualizzazione. Eccitando mediante opportuna radiazione ottica la fibra sotto test, è possibile ricavare la sua risposta spettrale, ossia determinarne le caratteristiche di emissione e assorbimento in funzione della lunghezza d'ond
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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