The spectral study of the glottal excitation has traditionally been based on a single time-domain mathematical model of the signal, and the spectral dependence on its time domain parameters. Opposite to this approach, in this work the two most widely used time domain models have been studied jointly, namely the KLGLOTT88 and the LF models. Their spectra are analyzed in terms of their dependence...

INTRODUCTION Adequate ventilatory support of critically ill patients depends on prompt recognition of ventilator asynchrony, as asynchrony is associated with worse outcomes.We compared an automatic method of patient-ventilator asynchrony monitoring, based on airway flow frequency analysis, to the asynchrony index (AI) determined visually from airway tracings. METHODS This was a prospective, s...

This study's aim was to determine if 6- and 9-month-old infants discriminate approximants and vowels when the spectral shape is modified to emphasize high- or low-frequency information. Infants were presented with /r/-/l/ and /ɔ/-/ɐ/ in three conditions: (a) unmodified; (b) -6 dB/octave tilt; and (c) +6 dB/octave tilt. Six-month-olds discriminated /ɔ/-/ɐ/ in conditions (a) and (b), and /r/-/l/ ...

The purpose of this study was to evaluate the effectiveness of several acoustic measures in predicting breathiness ratings. Recordings were made of eight normal men and seven normal women producing normally phonated, moderately breathy, and very breathy sustained vowels. Twenty listeners rated the degree of breathiness using a direct magnitude estimation procedure. Acoustic measures were made o...

The nature of the vocal-cord excitation has long interested speech researcher. One of the most important problems has been the specification of source excitations for speech synthesizers. It is known that the shape and periodicity of the vocal-cord excitation are subject to large variations. Investigations were carried out the effects of various glottal wave parameters on the synthesis of speec...

As research in speech processing has matured, there has been much interest in paralinguistic speech processing problems including the speaker’s mental and psychological health. In this study, we focus on speech features that can identify the speaker’s emotional health, i.e., whether the speaker is depressed or not. We use prosodic speech measurements, such as pitch and energy, in addition to sp...

In human speech production, the voice source contains important non-lexical information, especially relating to a speaker’s voice quality. In this study, direct measurements of the glottal area waveforms were used to examine the effects of voice quality and glottal gaps on voice source model parameters and various acoustic measures. Results showed that the open quotient parameter, cepstral peak...

Purpose: To measure tilt and decentration of intraocular lenses (IOLs) with Scheimpflug and Purkinje imaging systems. Methods: Measurements of IOL tilt and decentration were obtained using a commercial Scheimpflug system (Pentacam, Oculus) and custom algorithms, and a custom-built Purkinje imaging apparatus. Both methods were validated with a physical model eye where tilt and decentration can b...

Let Ω⊂ Rd be a bounded or an unbounded Lipschitz domain. In this note we address the problem of continuation of functions from the Sobolev space H1(Ω) up to functions in the Sobolev space H1(Rd) via a linear operator. The minimal possible norm of such an operator is estimated from below in terms of spectral properties of self-adjoint Robin Laplacians on domains Ω and Rd \Ω . Another estimate of...