Search results for "acústica"
showing 10 items of 28 documents
Prominence and centralization: a two-way contrast between lexical and epenthetic non-labial high vowels in Algherese Catalan
2015
Algherese Catalan has the peculiarity of presenting an inserted [i] vowel across words in order to avoid certain consonant codas. In this study, we compare five acoustic features of this epenthetic segment (i.e., duration, intensity, and the three first formants) with those of lexical /i/ vowels, both stressed and unstressed. The results indicate that the three vowels present differences only with respect to duration, F2 and, to a lesser extent, F3. The second formant values decline progressively from the lexical stressed vowels to the inserted unstressed segments, with lexical unstressed segments at an intermediate point. This gradation mirrors the relative prominence of each vowel. The di…
Sonic Gestures Applied to a Percussive Dialogue in TanGram using Wii Remotes
2009
TanGram, is an original music score composed by Carlos D. Perales for Percussion Quartet and Nintendo Wii Remotes used as a wireless interface for Live Electronics. This paper examines how this composition explores exiting research in interaction and communication between instruments and digital sound processing discourse to produce a unique music mixed-media score, to explore the sonic possibilities of a multi-timbrical instrument with the integration of the visual gestures of an accessible device using processes of real-time gestural mimesis. .
Física por un tubo. Mide la velocidad del sonido en el aire y diviértete con los tubos sonoros
2011
En este trabajo damos las claves para disenar un conjunto de tubos sonoros de PVC que permiten realizar una ejecucion musical en grupo con la participacion de un gran numero de personas sin cultura musical previa. Proponemos ademas la utilizacion de los tubos para el estudio cuantitativo de los fenomenos fisicos involucrados en la generacion del sonido con instrumentos de viento. Se describe la utilizacion de los tubos sonoros, en combinacion con un ordenador y un programa de analisis de sonido, para el analisis de ondas estacionarias y la determinacion de la velocidad de propagacion del sonido en el aire mediante distintos procedimientos.Palabras clave: Acustica; Ondas estacionarias; Veloc…
Surface Acoustic Bloch Oscillations, the Wannier-Stark Ladder, and Landau-Zener Tunneling in a Solid
2010
We present the experimental observation of Bloch oscillations, the Wannier-Stark ladder, and Landau-Zener tunneling of surface acoustic waves in perturbed grating structures on a solid substrate. A model providing a quantitative description of our experimental observations, including multiple Landau-Zener transitions of the anticrossed surface acoustic Wannier-Stark states, is developed. The use of a planar geometry for the realization of the Bloch oscillations and Landau-Zener tunneling allows a direct access to the elastic field distribution. The vertical surface displacement has been measured by interferometry.
Vocal communication in the Iberian wolf
2015
PARTE I. COMUNICACIÓN ACÚSTICA EN EL LOBO IBÉRICO El lobo (Canis lupus) es un carnívoro social cuya unidad básica de organización social es la manada, formada básicamente por una pareja reproductora y sus descendientes de varios años (Mech 1970, 1999). El número medio de lobos que integra una manada (tamaño de grupo) oscila entre 3 y 11 individuos (Fuller et al., 2003) y, en condiciones naturales, depende en gran medida de la disponibilidad de alimento (Mech & Boitani, 2003). Uno de los comportamientos más característicos y llamativos de los lobos es la emisión de aullidos para comunicarse a largas distancias. Quizá por este motivo la comunicación acústica de los lobos ha sido objeto de est…
Compact Mach-Zehnder acousto-optic modulator
2006
The authors demonstrate a compact optical waveguide modulator based on a Mach-Zehnder interferometer driven by surface acoustic waves. The modulator was monolithically fabricated on GaAs with an active region length of approximately 15μm. It yields peak-to-peak modulation exceeding 90% of the average transmission and operation in the gigahertz frequency range.
Polarized recombination of acoustically transported carriers in GaAs nanowires
2012
: The oscillating piezoelectric field of a surface acoustic wave (SAW) is employed to transport photoexcited electrons and holes in GaAs nanowires deposited on a SAW delay line on a LiNbO3 crystal. The carriers generated in the nanowire by a focused light spot are acoustically transferred to a second location where they recombine. We show that the recombination of the transported carriers occurs in a zinc blende section on top of the predominant wurtzite nanowire. This allows contactless control of the linear polarized emission by SAWs which is governed by the crystal structure. Additional polarization-resolved photoluminescence measurements were performed to investigate spin conservation d…
Los efectos de la contaminación acústica en la salud: conceptualizaciones del alumnado de Enseñanza Secundaria Obligatoria de Valencia
2010
Este trabajo parte de la hipótesis de que el alumnado de Educación Secundaria Obligatoria no considera la contaminación acústica, como un problema ambiental importante y desconoce sus efectos nocivos para la salud. A pesar de la importancia del ruido como contaminante ambiental en las sociedades modernas y de las consecuencias directas que tiene sobre la salud humana, el alumno de Secundaria no adopta una postura crítica al respecto, ni en los institutos, como parte fundamental del sistema educativo, ni en la sociedad como agente activo del futuro. This paper departs from the hypothesis that raises that the students of Secondary Obligatory Education do not consider the acoustic pollution to…
Acoustic properties and perception of minimal contrasts in Valencian Catalan sibilants
2017
El valencià estàndard presenta tres consonants fricatives sibilants: /s/, /z/ i /S/.Mentre que el contrast entre /z/ i /s/ sembla indiscutible, l’existència d’unaoposició real entre /S/ i /s/ és més dubtosa. El primer objectiu d’aquest treball éscomprovar si, en un estil de parla hiperarticulat (Fonet, Gonzàlvez et al., 2007), laconsonant /s/ és diferent de /z/ i de /S/ tenint en compte set paràmetres acústics:durada, harmonicitat, pic espectral i quatre moments espectrals: centre de gravetat,desviació estàndard, asimetria i curtosi. Les dades revelen que /z/ i /s/ contrastenclarament en durada, harmonicitat i asimetria; /S/ i /s/ contrasten en harmonicitat,desviació estàndard, curtosi i, e…
Acousto-optical multiple interference devices
2008
We present a new concept for waveguide acousto-optical devices based on coupled MachZehnder interferometers driven by acoustic waves. These acousto-optical multiple interference devices use the periodic refractive index modulation induced by the acoustic wave to realize functionalities such as ON/OFF switching for an arbitrary time interval, as well as for efficient light modulation at high harmonics of the acoustic frequency and pulse shaping for, e.g., integrated Q-switches. We also discuss application of the concepts to light modulation by very high acoustic frequencies, where the acoustic wavelengths become much shorter than the optical ones.