2,212 research outputs found
Acoustic Features and Perceptive Cues of Songs and Dialogues in Whistled Speech: Convergences with Sung Speech
Whistled speech is a little studied local use of language shaped by several
cultures of the world either for distant dialogues or for rendering traditional
songs. This practice consists of an emulation of the voice thanks to a simple
modulated pitch. It is therefore the result of a transformation of the vocal
signal that implies simplifications in the frequency domain. The whistlers
adapt their productions to the way each language combines the qualities of
height perceived simultaneously by the human ear in the complex frequency
spectrum of the spoken or sung voice (pitch, timbre). As a consequence, this
practice underlines key acoustic cues for the intelligibility of the concerned
languages. The present study provides an analysis of the acoustic and phonetic
features selected by whistled speech in several traditions either in purely
oral whistles (Spanish, Turkish, Mazatec) or in whistles produced with an
instrument like a leaf (Akha, Hmong). It underlines the convergences with the
strategies of the singing voice to reach the audience or to render the phonetic
information carried by the vowel (tone, identity) and some aesthetic effects
like ornamentation
Quantization of the Laplacian operator on vector bundles I
Let be a holomorphic Hermitian vector bundle over a polarized
manifold. We provide a canonical quantization of the Laplacian operator acting
on sections of the bundle of Hermitian endomorphisms of . If is simple
we obtain an approximation of the eigenvalues and eigenspaces of the Laplacian
Hydrodynamic and mass transfer efficiency of ceramic foam packing applied to distillation.
In addition to a high void volume and specific area, solid foams possess other properties (low density, good thermal, mechanical, electrical, and acoustical behaviour) that make them attractive for applications such as heat exchangers and reformers. Applications using foams as catalysts or structured catalyst supports have demonstrated higher performance than classical catalysts. Several studies have explored the hydrodynamic behaviour of foams in monophasic and counter current systems and have reported very low pressure drops. This paper describes the application of ceramic foam to distillation. The β-SiC foam contains 5 pores per inch (PPI) with a 91% void volume and a surface area of 640 m2/m3. Performance parameters including pressure drop for the dry and wet packing, flooding behaviour, and dynamic liquid hold-up were measured in a column of 150 mm internal diameter. The mass transfer efficiency in terms of the height equivalent to theoretical plate (HETP) was determined by total reflux experiments using a mixture of n-heptane and cyclohexane at atmospheric pressure. The experimental results were used to develop a set of correlations describing pressure drop and liquid hold-up in terms of a dimensionless number. The hydrodynamic performance and mass transfer efficiency were compared with classical packing materials used in distillation
The Study of tone and related phenomena in an Amazonian tone language: Gavião of Rondônia
This paper describes the methods used to study the tone and some related phenomena of the language of the Gavião of Rondônia, Brazil, which is part of the Mondé branch of the Tupi family. Whistling of words by indigenous informants was discovered to be a very effective method for obtaining phonetic accuracy in tone and length. Methods were devised to map out the system of tone and length. They were subsequently used in the study of other Amazonian languages, including Karitiana, Munduruku, Zoró, and Surui of Rondônia, with success. Some notes on tone considerations in orthography are offered, as well as notes on procedures that proved useful in the diachronic study of tone in the Mondé languages. Methods for the study of natural whistled speech used for distance communication are also described, with special attention to the whistled speech of the Gavião, including its use, its efficiency, and the whistling techniques used. The relation between some aspects of Gavião instrumental music and the suprasegmental aspects of the language are also discussed and the methods used to study this are described. Audio and video clips illustrate the phenomena being discussed. *This paper is in the series How to Study a Tone Language, edited by Steven Bird and Larry HymanNational Foreign Language Resource Cente
The Transformative Role of Telemedicine on Coordination: A Practice Approach
Delivering coordinated care at a distance challenges work practices and interprofessional collaboration. Using a case study methodology, we analyzed how three occupational groups, pathologists, technologists, and surgeons, coordinate work during the deployment of a major telepathology network in Eastern Canada. The aim of this study is to determine the extent to which and how telemedicine modifies coordination practices. \ \ Transformations emerged from our in-depth case analysis around three aspects of coordination: predictability, common understanding and accountability. First, predictability relied on routines in traditional settings, but shifted to a reliance on plans and rules in a telemedicine setting. Second, common understanding of the task shifted from relying on familiarity between stakeholders to an emphasis on standards. Third, accountability became less collective and more individual and contractual in a telemedicine setting, resulting in more marked boundaries between professional groups. Finally, proximity remained a determinant of accountability in telemedicine contexts, regardless of organizational arrangements. Implications for research and practice are discussed
Purification and characterization of a three-component salicylate 1-hydroxylase from Sphingomonas CHY-1
International audienceIn the bacterial degradation of polycyclic aromatic hydrocarbons (PAHs), salicylate hydroxylases catalyze essential reactions at the junction between the so-called upper and lower catabolic pathways. Unlike the salicylate 1-hydroxylase from pseudomonads, which is a well-characterized flavoprotein, the enzyme found in sphingomonads appears to be a three-component Fe-S protein complex, which has not so far been characterized. Here, the salicylate 1-hydroxylase from Sphingomonas CHY-1 has been purified and characterized with respect to its biochemical and catalytic properties. The oxygenase component called PhnII, exhibited an α3β3 heterohexameric structure and contained one Rieske-type [2Fe-2S] cluster and one mononuclear iron per α subunit. In the presence of purified reductase (PhnA4) and ferredoxin (PhnA3) components, PhnII catalyzed the hydroxylation of salicylate to catechol with a maximal specific activity of 0.89 U/mg and showed an apparent Km for salicylate of 1.1 ± 0.2 µM. The hydroxylase exhibited similar activity levels with methylsalicylates and low activity with salicylate analogues bearing additional hydroxyl or electron-withdrawing substituents. PhnII converted anthranilate to 2-aminophenol and exhibited a relatively low affinity for this substrate (Km = 28 ± 6 µM). 1-Hydroxy-2-naphthoate, which is an intermediate in phenanthrene degradation, was not hydroxylated by PhnII, but induced a high rate of uncoupled oxidation of NADH. It also exerted a strong competitive inhibition of salicylate hydroxylation, with a Ki of 0.68 µM. The properties of this three-component hydroxylase are compared with those of analogous bacterial hydroxylases and discussed in the light of our current knowledge of PAH degradation by sphingomonads
Amending Contracts for Choreographies
Distributed interactions can be suitably designed in terms of choreographies.
Such abstractions can be thought of as global descriptions of the coordination
of several distributed parties. Global assertions define contracts for
choreographies by annotating multiparty session types with logical formulae to
validate the content of the exchanged messages. The introduction of such
constraints is a critical design issue as it may be hard to specify contracts
that allow each party to be able to progress without violating the contract. In
this paper, we propose three methods that automatically correct inconsistent
global assertions. The methods are compared by discussing their applicability
and the relationships between the amended global assertions and the original
(inconsistent) ones.Comment: In Proceedings ICE 2011, arXiv:1108.014
Low-power, 10-Gbps 1.5-Vpp differential CMOS driver for a silicon electro-optic ring modulator
We present a novel driver circuit enabling electro-optic modulation with high extinction ratio from a co-designed silicon ring modulator. The driver circuit provides an asymmetric differential output at 10Gbps with a voltage swing up to 1.5V(pp) from a single 1.0V supply, maximizing the resonance-wavelength shift of depletion-type ring modulators while avoiding carrier injection. A test chip containing 4 reconfigurable driver circuits was fabricated in 40nm CMOS technology. The measured energy consumption for driving a 100fF capacitive load at 10Gbps was as low as 125fJ/bit and 220fJ/bit at 1V(pp) and 1.5V(pp) respectively. After flip-chip integration with ring modulators on a silicon-photonics chip, the power consumption was measured to be 210fJ/bit and 350fJ/bit respectively
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