1,759,058 research outputs found
Giglia, V.F.
No full textCentro Asturiano membership record of V.F. Giglia; Socio Number: 102724.https://digitalcommons.usf.edu/asturiano_membership/3081/thumbnail.jp
Expectations and the behaviour of Spanish treasury bill rates
No full textRational Expectations models are tested here under the standard assumptions of the Expectations Hypothesis (EH) of interest rates. We examine the theoretical unbiasedness of the spread of interest rates by predicting changes in the shorter spot rates. Unit root tests are applied and VAR systems are specified as a framework to apply Johansen's Maximum Likelihood Cointegration Analysis. Homogeneity and exogeneity tests are also carried out. Finally, we provide some Vector Error Correction Models (VECM) to determine the significance of the main assertions of the EH. Our VECM are coherent with the EH. We conclude that, by providing stability and strengthening the monetary transmission mechanism, the Spanish Treasury bills played a very relevant role in the monetary policy applied in Spain in order to enter the EMU
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
Non-linear propagation for medical imaging
No full textThe propagation of high amplitude ultrasonic fields, such as those generated by some medical ultrasound systems, is not adequately described by the linear wave equation. Instead it is necessary to consider non-linear propagation if the drive levels are high
enough to make non-linear effects significant. As a result of non-linear propagation the transmitted waveforms distort as they propagate, resulting in the generation of harmonics of the initial frequency components transmitted by the transducer. In the nearfield of medical transducers diffraction and focusing effects associated with the source complicate this process.The basic physics of this non-linear propagation is reviewed and the complex characteristics of the finite amplitude fields generated by different sources are described. This is illustrated with both experimental results and numerical predictions obtained using a finite difference solution (the Bergen Code) to the Khokhlov-Zabolotskaya-Kuznetsov (or KZK) equation. The fields of both ideal sources and real medical systems are demonstrated. The use of harmonics to improve image quality is then considered, with the characteristics of the fields produced by harmonic imaging and pulse inversion systems being compared. The implications of non-linear propagation for medical ultrasound output regulation are also considered
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
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