bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying musical acoustics through audibility
Authors: Griesinger David H.
Published: October 2005

This paper proposes a set of measures of musical acoustics derived from a study of binaural hearing and speech perception. The measures are tested on analyzing data from unoccupied and occupied halls, data from several halls which include electronically variable acoustics capable of a wide range of adjustment, and data from a binaural synthesizer of hall acoustics. The new measures include the 500-ms reverberant level (L500), early (0–60 ms) reverb time (ERT), middle (0.1–0.5 s) reverb time (MRT), late (0.5+) reverb time (LRT), early binaural fraction (EBF), and middle binaural fraction (MBF). L500, a measure of reverberant level, is related to early decay time (EDT). Optimum L500 is found to be high in the range of musical fundamentals, and low in the region of maximum speech information. ERT is in part a measure of the localizability of the sound, which is related to its clarity. MRT is particularly significant whenever the decay curve is not a simple exponential. It is found that when MRT is much longer that ERT the sound can be both clear and reverberant at the same time. The binaural measures are found to be similar to IACC, but have advantages at frequencies below 300 Hz. Some implications of this research on optimum hall shape and surface treatment are discussed.
Determination of the meter of musical scores by autocorrelation
Authors: Brown Judith C.
Published: October 2005

A single voice extracted from the scores of compositions from the Baroque, Classical, Romantic, and Contemporary periods has been studied in order to determine the feasibility of the determination of musical meter by computer. The method of autocorrelation is appropriate for this calculation since it is a measure of the frequency of occurrence of events following an event at time zero. If a greater frequency of events occurs on the downbeat of a measure as predicted by Palmer and Krumhansl [‘‘Mental Representations for Musical Meter,’’ J. Exp. Psychol.: Hum. Percept. Perform. 16, 728–741 (1990)], then a peak in the autocorrelation function should indicate the time for a single measure. The results of these computations indicate that computer determination of meter from score events is indeed possible. An example is included to show that this method of analysis can be applied to live performance data as well.
Spectral-shape features versus formants as acoustic correlates for vowels
Authors: Zahorian Stephen A. , Jagharghi Amir Jalali
Published: October 2005

The first three formants, i.e., the first three spectral prominences of the short-time magnitude spectra, have been the most commonly used acoustic cues for vowels ever since the work of Peterson and Barney [J. Acoust. Soc. Am. 24, 175–184 (1952)]. However, spectral shape features, which encode the global smoothed spectrum, provide a more complete spectral description, and therefore might be even better acoustic correlates for vowels. In this study automatic vowel classification experiments were used to compare formants and spectral-shape features for monopthongal vowels spoken in the context of isolated CVC words, under a variety of conditions. The roles of static and time-varying information for vowel discrimination were also compared. Spectral shape was encoded using the coefficients in a cosine expansion of the nonlinearly scaled magnitude spectrum. Under almost all conditions investigated, in the absence of fundamental frequency (F0) information, automatic vowel classification based on spectral-shape features was superior to that based on formants. If F0 was used as an additional feature, vowel classification based on spectral shape features was still superior to that based on formants, but the differences between the two feature sets were reduced. It was also found that the error pattern of perceptual confusions was more closely correlated with errors in automatic classification obtained from spectral-shape features than with classification errors from formants. Therefore it is concluded that spectral-shape features are a more complete set of acoustic correlates for vowel identity than are formants. In comparing static and time-varying features, static features were the most important for vowel discrimination, but feature trajectories were valuable secondary sources of information.
Speech perception without audition
Authors: Bernstein Lynne E. , Demorest Marilyn E.
Published: October 2005

Most knowledge about speech perception is within the framework of studies concerned with acoustic-phonetic stimulus attributes. Vision is known to affect speech perception but is typically considered only as a supplement to hearing. The literature contains assertions that only 30% of words are recognized in lipreading/speechreading and that hearing subjects are more accurate than deaf subjects. Observations of expert visual speech perception among some profoundly deaf subjects [L. E. Bernstein etal., J. Acoust. Soc. Am. 90, 2971–2984 (1991)] promoted questioning of the conventional wisdom. A normative study of lipreading was therefore conducted involving 96 hearing and 72 deaf young adults. The two populations differed significantly across nonsense syllable, word, and sentence identification measures. The most accurate subjects were from within the deaf population. Results that lipreading in some deaf subjects is comparable to listening to speech in noise by hearing subjects. Expert lipreading demonstrates that speech perception does not require audition. Speech perception appears to be fundamentally the perception of linguistic entities not acoustic-phonetic attributes. Theories of speech perception for which generality is claimed need either to account also for visual speech perception or need to limit their claims to generality.
Effects of hearing differences on encoding and comparison information-processing stages
Authors: Seitz Philip F. , Rakerd Brad , Tucker Paula E.
Published: October 2005

Reaction times to spoken digits presented in a speeded memory scanning procedure were measured for groups of listeners with normal hearing (N=24) and with congenital or early-onset sensorineural hearing losses (N=12). Separate groups of 12 normal-hearing listeners were tested under conditions of good stimulus quality (no distortion, high SNR) versus poor stimulus quality (low-pass filtered, low SNR). The speeded memory scanning procedure allows total reaction time to be decomposed into ‘‘encoding’’ and ‘‘comparison’’ components which correspond to separate stages in a model of human information processing. At issue here is whether long-term effects of hearing loss, such as possible deficits in phonological and/or lexical representation of spoken language, lead to unusual processing costs at either the encoding or comparison stage. Experimental results suggest that impaired listeners incur the same encoding costs as normal-hearing listeners presented with poor-quality stimuli. However, comparison costs for the impaired listeners are no higher than those for the normal-hearing listeners presented with good-quality stimuli, and are unexpectedly lower than those for the normal-hearing listeners presented with poor-quality stimuli. [Work supported by NIH-NIDCD.]
Speaker-independent recognition of children’s words with minimal phonemic contrast
Authors: Kewley-Port Diane , Mills Bill , Dalby Jonathan
Published: October 2005

Speaker-independent speech recognition can be used in speech training applications to provide feedback on phonemic contrasts. Our application is drill for normal-hearing misarticulating children with target-substitution errors (e.g., /r/→/w/ or /s/→/θ/). Six word pairs incorporating eight common misarticulations in word initial, medial, and final positions were repeated twice for a total of 192 words. These phonemic contrasts are extremely challenging for most recognizers. Seventeen children in third to fifth grade repeated the word list once. Two other children and an adult repeated it seven times to provide speaker-dependent comparisons. The Scott SIR 20 recognizer was evaluated. Speaker-independent templates were made in round-robin fashion, leaving out one child each time for testing. The overall recognition rate for the 16 tests was 75.3% correct, with a range of 85.3% for the best (/s–∫/) phonemic contrast, to 65.5% for the worst (/d–δ/). Human recognition of a subset of the words was also shown to vary across phonemic contrasts. Analyses of the linguistic content of the word pairs and comparisons with the speaker-dependent recognition results indicate that speaker-independent recognition is accurate enough for some minimal phonemic contrasts to be used in speech drill. [Work supported by NIDCD.]
Perception of stop consonants in speech signals reconstructed from phase or amplitude
Authors: Liu L. , He J. L. , Palm G.
Published: October 2005

It is well known that under certain conditions, a signal is completely specified either by its Fourier transform phase or amplitude. An iterative technique similar to that used by Hayes etal. [IEEE Trans. Acoust., Speech, Signal Process. ASSP-28, 672–680 (1980)] was applied to the global Fourier transform phases or amplitudes of natural VCV (vowel–stop consonant–vowel) utterances and the perception of stop consonants was experimentally studied. Under a variety of conditions, the consonant identification performance in the phase-only stimuli improved from about 66% to more than 90% after the iterations. The influence of the initial amplitude guess on the quality of the reconstructed signals was also investigated. The retrieval of stop consonant information from phase for various window lengths and various phase noise levels were analyzed with regard to vowel contexts, stop manner, and place of articulation. In contrast to the case of signal reconstruction from its phase, the stimulus reconstructed from the amplitude was found not of much value in representing the original VCV signal. Little improvement on consonant perception could be made after the iterations if a flat or a random phase was taken as the initial guess. However, with an appropriate choice of the initial guess, which contains one bit of the original phase information, stimuli with near-perfect consonant identification performance were reconstructed.
Can lexical knowledge inhibit phoneme perception?
Authors: Wurm Lee H. , Samuel Arthur G.
Published: October 2005

This series of experiments tests a critical prediction of the TRACE model of speech perception [J. L. McClelland and J. L. Elman, Cog. Psychol. 18, 1–86 (1986)]. Experiment 1 was a replication [U. H. Frauenfelder, J. Segui, and T. Dijkstra, JEP:HPP 16, 77–91 (1990)]. Subjects listened to lists of words and non-words, and made speeded detection responses to specified phoneme targets. In accord with the Frauenfelder etal. result, experiment 1 produced no evidence of inhibitory lexical effects on phoneme monitoring reaction times. Experiment 2 improved several design aspects of the Frauenfelder etal. experiment by using balanced target locations, increasing the number of critical stimuli, and using a more appropriate baseline condition against which to measure inhibitory effects. The results of this line of research clarify whether indirect lexical inhibition should be included in models of lexical access.
The perception of chirps by Sykes’ monkeys and humans
Authors: Brown Charles H. , Sinnott Joan M. , Kressley Regina A.
Published: October 2005

Four Sykes’ monkeys (Cercopithecusalbogularis) and three humans discriminated among 12 chirps presented in a repeating background paradigm. The test stimuli consisted of sets of four chirps recorded from Sykes’ monkeys, red-tailed monkeys (Ce. ascanius), and small East African birds, respectively. Reaction times were submitted to a multidimensional scaling analysis (ALSCAL). All monkey listeners perceived the bird chirps as similar to each other, and distinct from the monkey calls, while two of the three human listeners had difficulty distinguishing the bird chirps from the monkey calls. Both human and monkey subjects tended to exhibit overlapping maps for the Sykes’ and red-tailed calls, but the magnitude of overlap tended to be greatest for the monkey listeners. Guenon monkeys give chirps in similar alarm contexts, and these calls alert members of sympatric species to common dangers. Conversely, bird chirps are very commonly heard, are not associated with alarm, and must constitute for monkeys an acoustical impediment to communication. The present data suggest that the monkey’s perceptual map of these highly similar calls is influenced by the biological significance of these calls in nature. [Work supported by NIDCD.]
Implementation of generalized impedance boundary condition in the split-step Fourier parabolic equation
Authors: Ryan F. J.
Published: October 2005

The parabolic wave equation (PE) is a powerful numerical method for computing the full-wave complex acoustic pressure field in range-dependent environments. The split-step Fourier PE algorithm (SSFPE) of Hardin and Tappert provides a very efficient computational implementation of PE when the surface boundary condition is of the Dirichlet or Neumann form, and when the solution decays sufficiently with depth. This allows use of fast Fourier transform (FFT) methods to implement the SSFPE algorithm. Typically the infinite domain radiation condition is approximated on a finite calculation grid by employing an artificial absorber or sponge. In some cases involving strong bottom interaction, however, the required absorber region may be quite large. This results in an increased computational load. A new method for truncating the absorber region will be described that is based upon splitting the PE field into two components that are in turn propagated on different vertical wave-number grids. Illustrative examples that use this new method will be shown. [Work supported by NRaD IR program.]
Minimax rational approximations for the parabolic equation method
Authors: Collins Michael D.
Published: October 2005

Higher-order Padé approximations have been applied to reduce the limitations and to improve the efficiency of the parabolic equation (PE) method [M. D. Collins, J. Acoust. Soc. Am. 93, 1736–1742 (1993)]. Several of the derivatives are correct at the origin for Padé approximations. Improved efficiency may be achieved by using rational approximations designed using the minimax method, which involves minimizing the maximum error over a domain of interest. This approach has been applied for deriving a PE for fluid media that handles wide propagation angles [Vefring and Mjo/lsnes, J. Acoust. Soc. Am. 93, 1736–1742 (1993)]. Additional applications of the minimax approach include deriving improved approximations for the elastic PE (for which stability is an important issue), the two-way PE (which may require a careful treatment of the evanescent spectrum), and the split-step Padé solution (which involves that approximation of a relatively complicated function).
Propagation and signal coherence in bottom-limited shallow water environments
Authors: Ryan F. J. , Shook L. A.
Published: October 2005

Simulation results will be presented for complex shallow water environments off the southern California coast. The study focuses on downslope propagation from sources in shallow water to deeper bottomed sensors. The environment is a thinly sedimented series of terraces separated by steep slopes. A very high fidelity geoacoustic bottom model, SEABEAM-type bathymetry and dense synoptic oceanographic measurements are used to compute pressure fields using PE codes. Examples of spatial signal coherence and spatial variability will be shown. The question of the effects of environmental data spatial resolution (bathymetry and sub-bottom) on computed signal fields will be addressed.
A fast one-way normal mode propagation method
Authors: White E. , Werby M. F.
Published: October 2005

The development of a new fast normal mode method produces vertical wave functions that are in closed form. One-way coupled mode methods can be based on projection matrices that are generated by integral overlaps between vertical wave function of adjacent domains. For methods that require numerical solutions of the vertical wave functions the computation of the matrix elements is very time consuming and can even lead to inaccuracies at higher frequencies. However the closed form solutions allow one to code matrix elements in relatively simple closed form based on simple arithmetic sums. This leads to a rapid method for generating the projection matrices and therefore connects the stepwise domains in a rapid fashion. The method is tested and compared with other available coupled mode programs. Ultimately the method will be used for the object in a waveguide program for which this method was originally designed. [Work supported by Naval Research Laboratory 6.1 program (element 601153N) with technical management provided by NRL-SSC.]
Intrinsic F0 in the babbling of infants at ages 6, 9, and 12 months
Authors: Whalen D. H. , Levitt Andrea G. , Smorodinsky Iris , Hsiao Pai-Ling
Published: October 2005

In adult speech, fundamental frequency (F0) has been found to be relatively high with high vowels and low with low vowels. This ‘‘intrinsic pitch’’ has been found in every language examined, including tone languages. One study with infants [Bauer, Folia Phonia. 40, 138–146 (1988)] found that F0 changed consistently with the front/back dimension rather than the high/low dimension. Bauer interpreted this pattern in terms of the change in vocal tract shape that occurs over the first 18 months of life. In this study, four infants were examined at 6, 9, and 12 months of age. Only vowels with non-mid-central articulation were selected. Results indicated that there was, after all, an association with height, though there was also an interaction with front/back. Reasons for the discrepancy with earlier work will be discussed. [Work supported by NIH Grant No. DC-00403.]
Analysis of the acoustic field via spectral decomposition
Authors: Norton Guy V.
Published: October 2005

Spectral decomposition has been used by various authors as a calculation technique for acoustic propagation in range independent and recently range dependent ocean environments. One of the methods’ strong points is that it maps the initial acoustic field at each given depth point in the waveguide into horizontal wavenumber space. Since the field is now expressed in wavenumber space, analogous to normal mode theory, various acoustic quantities can easily be calculated. These quantities such as the group velocity or the incident field expressed in terms of the plane wave spectrum in the past were calculated using normal modes. However, since all that is required to initiate the method is a complex acoustic field evenly space in depth of the waveguide, the method has been coupled to the output of a PE model, in order to analyze that field. The associated theory and numerical examples will be given. [Work sponsored by ONR.]
Some observations of acoustic variability and array performance at short range near Vestfjorden
Authors: Del Balzo Donald R.
Published: October 2005

An experiment was conducted in October 1989 in shallow water (250-320 m) near Vestfjorden in support of sonar system research at SACLANTCEN. This talk describes some observations of acoustic variability and array performance at short range for one-way pulse propagation during a 46-min period. The signals were 0.5-s LFM pulses in the frequency band of 340–345 Hz. They were received at a range of 13 km on 59 elements of a towed array. Large variability in the received signal level across the array, by as much as 10–15 dB, was observed on some individual pulses. These acoustic variations appear to be related to depth variability along the array due to a small array tilt. Normal mode calculations in this environment indicate the existence of a deep acoustic null in the vicinity of the measured data. Average array signal gain degradation for all data with SNR≳20 dB is only 0.6 dB, so the array beamforming performance is close to the theoretical maximum on this 27-wavelength aperture in shallow water.
Shell function method incorporated ray representation for computing the acoustic pressure field in inhomogeneous media
Authors: Pan Haitao , Ohstuki Shigeo
Published: October 2005

The Shell function method is presented as a new technique to evaluate the acoustic pressure field, produced by a practical source of finite area, in a medium having an arbitrary spatially varying sound speed. The Shell function method considers the acoustic wave received at the observation point, for a specified travel time, and the associated vibrating source area. In terms of ray representation, this approach is accomplished by interchanging the position of the observation point with that of the elemental area of the source. Both the convergent state of a sound beam issuing from the observation point, and the element area of the source responsible to this convergent state, are taken into account simultaneously. As a consequence, the sound pressure at, and in the vicinity of, caustics can be given an appropriate value directly. The Shell function method was evaluated by the computation of the acoustic field in a depth-dependent sound-speed profile containing caustics, for a linear source with a specified length.
Observation of the prompt high-frequency enhancement of tone bursts backscattered by a thin spherical shell near the first longitudinal resonance
Authors: Kaduchak Gregory , Marston Philip L.
Published: October 2005

A prominent feature predicted for the backscattering of tone bursts by thin spherical shells is an enhancement of a guided wave contribution near the first longitudinal resonance. This has been explained with a backward ray model of a leaky Lamb wave where energy is leaked off without having circumnavigated the back side of the shell [P. L. Marston etal., J. Acoust. Soc. Am. 90, 2341 (1991); D. H. Hughes, Ph.D. thesis, Washington State University (1992)]. The relevant s2b Lamb wave has opposing group and phase velocities giving rise to prompt radiation following the direct specular echo. The present research gives a comparison between a ray theory approximation and experiments in which tone bursts having carrier frequencies in the range 595<ka<640 were incident on an empty stainless steel spherical shell in water of radius a=12.7 cm. The sphere’s thickness to radius ratio is 2%. The response generally follows the predicted amplitude which can be close to 4.5 times the specular amplitude. [Work supported by ONR.]
The influence of internal structures on bistatic scatter from finite cylindrical shells near axial incidence
Authors: Conti Matthew , Dyer Ira
Published: October 2005

Previous results have examined the scatter for an empty shell at axial incidence illustrating the primary role of the endcap. Building on this, important differences in the bistatic scatter due to the presence of internal structures are presented. In addition, differences due to source incidence away from axial are investigated. Discussion is based upon bistatic measurements on an empty shell with endcaps, a duplicate shell with internal ring stiffeners and a duplicate ring stiffened shell with resiliently mounted wave-bearing internal structures. Integrated target strengths shown as a function of observation angle reveal spatial regions where the internal structures cause significant change. Of particular interest is enhancement of target strength near backscatter. In conjunction with conventional beamforming techniques, these analyses reveal the distribution of energy along the shell length. This distribution is modified by rotation of incidence away from axial. Relative decay rates and frequency-dependent effects are also discussed. The bistatic measurements were conducted over a frequency range of 2.5<ka<10, corresponding to 3/4 to 3 times the ring frequency of the shells. [The authors acknowledge the assistance of NRL for acquisition of data. Work supported by ONR.]
Experimental investigation of nonspecular scattering from a framed shell
Authors: Houston Brian H. , Bucaro Joseph A. , Photiadis Douglas M.
Published: October 2005

Recently the existence of flexural Bloch waves contributing significantly to features observed in far-field experimental data was reported [Photiadis etal., J. Acoust. Soc. Am. 93, 2413(A) (1993)]. In this previous work, broadband scattering data from framed and unframed low aspect ratio fluid-loaded shells (l/a=3) were studied. Calculations of the dispersion curves for an infinite ribbed shell were used to predict the locations of the peaks in the backscattered cross section. Here, the results of the scattering from a high aspect ratio (l/a=8) pseudoperiodically framed shell are reported. The various elastic wave types using the infinite framed shell dispersion relations are identified and the relevant contributions are quantified.
Wave vector measurements of empirical design transfer functions
Authors: Clark Joseph A. , Sartori Michael A.
Published: October 2005

Empirical design transfer functions can be used to predict the radiated noise generated from various components in a system. The Darby method is one example of an approach used to find these empirical design transfer functions. For an immersed and radiating structure, near-field measurements of the pressure field can be wave vector filtered to find the empirical design transfer function from the structural input point to the acoustic far field. Assuming a cylindrical body excited by a force and radiating, a discrete line array of pressure sensing devices are used to measure the near-field pressure. The acoustic pressure data measured at each point are sampled, digitized, time averaged, and frequency transformed. The position-frequency domain pressure is then transformed into the wave vector domain, and the far-field radiation is predicted. The empirical design transfer function is found by dividing the predicted far-field radiation by the input force. The mathematical development of this approach is presented. Simulations are presented for various radiation sources, including a monopole and a discrete line source. The pressure predictions of the wave vector are compared with the pressure directly computed for the sources. [Work supported by ONR.]
The influence of stress, vowel, and juncture cues on segmentation
Authors: Yerkey Paul N. , Sawusch James R.
Published: October 2005

Cutler and Norric [JEP:HPP 14, 113–121 (1988)] proposed a segmentation strategy based on strong syllables. According to their strategy, a listener attempts lexical access every time a strong syllable is heard. In a word monitoring task, Cutler and Norris found support for this strategy with speakers of British English. However, in the Cutler and Norris experiments, the strong syllables used were characterized by strong stress, a tense vowel, and the possible presence of allophonic cues to word junction. Thus the relative roles of these cues in segmentation is still to be determined. As reported at previous meetings of the Acoustical Society, Yerkey and Sawusch [J. Acoust. Soc. Am. 91, 2338(A) (1992), J. Acoust. Soc. Am. 92, 2443(A) (1993)] examined this issue by separating syllable stress and vowel color in an attempt to determine their relative roles as cues to segmentation. The results of these experiments suggest that, for American English, syllable stress is a primary cue for segmentation, and vowel color does not seem to have an important influence. The present study extends these results by evaluating the role of allophonic juncture in word segmentation.
Development of the song selectivity by nonlinear neural response interactions in the zebra finch
Authors: Lim Dukhwan
Published: October 2005

The zebra finch’s song control system contains song-selective neurons. One of the song nuclei, hyperstriatum ventral, caudal (HVc) receives auditory inputs from the forebrain auditory area, field L, which is subdivided into L1, L2, and L3. Where and how this selectivity is formed has not been studied quantitatively in this forebrain area. The song of the zebra finch consists of simultaneous and sequential arrangements of acoustic elements. Neuronal responses to individual song elements and to syllables composed of harmonic frequencies were studied in each subdivision of field L and HVc. The responses to pairwise sequences or harmonic syllables differed from their responses to an individual element or a tone presented in isolation. These nonlinear responses were evaluated by a matrix-based analysis method. Results showed a hierarchical increase of nonlinear interactions as a recording site moved from field L to HVc. Both sequential and simultaneous nonlinear interactions were enhanced from field L to HVc. These interactions involved either inhibitory or facilitatory effects. Although, in theory, this selectivity could be formed by a linear way, the song selectivity proved to be achieved dominantly by these nonlinear interactions. [Work supported by IHFSPO.]
Relative perceptual prominence of fundamental frequency peaks in the presence of declination
Authors: Repp Bruno H. , Rump H. H. , Terken Jacques M. B.
Published: October 2005

Two experiments were conducted to determine the perceived relative prominence of two accented syllables within the same utterance. The fundamental frequencies (F0) at the two accent peaks (P1,P2) were varied as well as the rate of F0 declination over the unaccented syllables. Extending earlier work by Terken [J. Acoust. Soc. Am. 89, 1768–1776 (1991)] with low-pitched reiterant speech, a real Dutch sentence was employed in both female and male pitch ranges. The results confirm earlier observations that P2 is usually lower than P1 when judged to be equal in prominence, and that this difference increases with P1 height. However, this second effect diminishes as declination rate increases. The results do not fit any simple model of prominence perception based on distance from a reference declination line. [Work carried out at IPO, Eindhoven.]
Aural differentiation of related speakers
Authors: Krebber Winfried , Rinas Vigo
Published: October 2005

Motivated by the well-known identification problems in telephone communication, this study investigates the influence of filtering on the aural differentiation of related speakers (e.g., father and son). Speech samples of couples of related speakers were presented to 30 listeners in 14 sessions (1 couple/session). Each session started with a reference sample to acquaint the listeners with one speaker of the couple. Subsequently the listeners received samples of both speakers and had to detect the samples belonging to the acquainted speaker. Additionally they gave information about the certainty of their decision using the terms ‘‘surely,’’ ‘‘probably,’’ or possibly.’’ The following speech samples were used: voiced vowels and (unknown) sentences, unfiltered and filtered with several bandpass filters; voiced vowels without higher formants (only F1 left), and whispered vowels. In an additional opinion test the similarity of both voices of each couple was rated. The rates of false identifications depend clearly on the filter bandwidth. For voiced vowels there is a good correlation between the subjective similarity and the rates of false identifications, but not for sentences. Speech transmitted by usual telephone handsets, applied with an acoustical leakage to the ear, results in very high false identification rates (up to 45%).
Acoustic features as indices of emotional responding following reward and failure feedback
Authors: Bachorowski Jo-Anne , Linker Christopher D. , Owren Michael J.
Published: October 2005

Comprehensive models of personality regard individual differences in emotional responding as important mediators of behavior across a variety of contexts. However, traditional psychophysiological and self-report measures are often unreliable or unwieldy when applied to emotional responses. Several acoustic features were examined as indices of changes in emotional state. Adult subjects were given noncontingent positive and negative feedback as they participated in a computerized lexical decision task. Acoustic components were extracted from discrete speech segments recorded immediately following feedback. In comparison to baseline recordings, higher F0 values were associated with both positive and negative feedback. However, changes in jitter and shimmer were differentially associated with the type of feedback in that increases in these perturbation measures were especially apparent following negative feedback. The results of this research will be used to elaborate the cognitive and emotional processing of trait-anxious and trait-impulsive individuals in contexts designed to engender anxious and impulsive behavioral responses.
Perception of multiple levels of prominence in spontaneous speech
Authors: Wightman Colin W.
Published: October 2005

In both read and spontaneous speech, phrasal prominences play an important role in conveying the speaker’s intent. Prominences serve both to mark important discourse-related events in the conversation and help to resolve ambiguities at several levels. Many speech researchers report the intuition that there are several levels of prominence, that is, that some prominences are bigger than others. Nonetheless, attempts to train human labelers to mark multiple levels of prominence have not been successful: while there was agreement on the location of prominences, there was little agreement between labelers on the level to be assigned to each. Here, an alternative approach, using a panel of naive listeners to mark prominences in a corpus of spontaneous speech has been taken. Instead of marking multiple levels of prominence, a simple binary labeling was used by each labeler and the level of each prominence determined by the number of labelers marking it. In this paper, the results of this preliminary study are presented, and the relationships between the estimated levels of prominence and the acoustic correlates of vowel lengthening, syllable lengthening, and pitch level and excursion are investigated.
Can you rustle up some attention?: Further results on breath sounds in synthesis
Authors: Sheffert Sonya M. , Whalen D. H. , Hoequist Charles E.
Published: October 2005

During conversation, speakers typically take a breath when preparing to speak. At the previous meeting [Whalen and Hoequist, J. Acoust. Soc. Am. 93, 2298(A) (1993)], it was shown that subjects were significantly more accurate at transcribing synthesized sentences that were preceded by a (naturally produced) breath intake than those that were not. It was concluded that the perception of synthetic speech is facilitated by the addition of a breath, presumably because it increased the naturalness of the stimuli. However, there is the possibility that this result is simply due to the extra attention-getting effect of the breath between the warning tone and the sentence. To test this possibility, the breath was replaced with the sound of rustling leaves. The rustling sounds matched the breaths in duration and loudness. The results should tell us whether the presence or absence of a breath before a synthesized sentence functions as a cue for the upcoming speech, or merely as a general attention-orienting sound. [Work supported by NIH Grant No. HD-01994.]
Changes in voice-onset time in speakers with cochlear implants
Authors: Lane Harlan , Wozniak Jane , Perkell Joseph , Matthies Melanie , Svirsky Mario
Published: October 2005

Voice-onset time (VOT) was measured for the English plosives in /Copen aye/ context spoken by three female and one male postlingually deafened recipients of multi-channel (Ineraid) cochlear implants. Recordings were made of their speech before activation of their speech processors and at intervals after activation, extending over several years. Also measured were: instantaneous oral airflow; sound pressure level; an indirect index of glottal aperture; and average airflow during passage readings. Pre-implant, all four speakers characteristically uttered plosives with too-short VOT, compared to normative data. After activation of their processors, all four were relatively accurate in identifying plosives with respect to voicing, and the three female speakers lengthened VOT. The women also increased glottal aperture post-activation. However, none of the women increased peak oral flow following plosive release, possibly because of a countervailing decrease in subglottal pressure: all three reduced SPL post-activation. Complementary results were found for the male speaker: a decrease in inferred glottal aperture and an increase in oral flow accompanied by an increase in SPL. Increases in glottal aperture are expected to inhibit the onset of voicing in the plosives [K. Stevens, Phonetica 34, 264–279 (1977)]. Consequently, some or all of the observed increases in VOT with activation of the implant processors may be due to ‘‘postural’’ adjustments of the larynx. [Work supported by N.I.D.C.D.]
A multidimensional numerical algorithm to simulate the propagation of a shock wave through caustics
Authors: Piacsek Andrew A.
Published: October 2005

One strategy in the effort to explain features of observed sonic boom profiles that deviate from the classical N shape is to simulate, one a computer, the propagation of shock waves in an inhomogeneous medium. A time-marching finite-difference code is being developed by the author which employs a multidimensional explicit flux corrected transport scheme, based on work by Zalesak [J. Comp. Phys. 31, 335–362 (1979)] and McDonald (NPE source code and private communication). Certain essential features of the program have been examined by comparing the results of some simplified cases to published results of other numerical schemes and, where they are known, to analytical solutions. Specifically, results will be shown regarding the code’s ability to simulate the 2-D linear propagation of a curved shock wave front in a homogeneous medium, and 1-D nonlinear propagation of pulses with dissipation and molecular relaxation. Also presented will be some results of 2-D nonlinear propagation, in which an N wave with a curved wave front passes through a caustic. [Work supported by NASA and the William E. Leonhard endowment to the Pennsylvania State University.]
Connection between structural and statistical models of atmospheric turbulence
Authors: Goedecke George H. , Pellegrino Paul M. , Auvermann Harry J.
Published: October 2005

A structural model of isotropic homogeneous atmospheric turbulence is presented, in which the turbulence is described as an ensemble of individual localized quasistatic eddies or turbules. Turbules of different sizes a are assumed self-similar with respect to their temperature and flow velocity fields, and randomly positioned and oriented with no correlations. It is shown that, in order to obtain agreement with the Kolmogorov acoustical scattering spectrum, the usual relation between turbule flow speed v and size, v∝a1/3, must be assumed, and, in addition, (i) turbule number densities must be proportional to a−3, and (ii) turbule sizes must be in a geometric sequence, from the outer scale to the inner. It is also shown that the Kolmogorov spectrum is insensitive to the turbule morphology, and that the extent of the ‘‘inertial range’’ is influenced only weakly by the morphology. Expressions for CT2 and Cv2, and for the boundaries of the inertial range, are derived in terms of the structural parameters.
Comparisons of experimental measurements of sound propagation over a hill and the polar parabolic equation method
Authors: You Chulsso , Bass Henry E. , Gilbert Kenneth E.
Published: October 2005

The polar parabolic equation (POPE) method, which introduces the boundary fitting coordinates into the parabolic equation (PE) method, was developed to solve for sound propagation over a curved surface and over irregular terrain (hills) [X. Di etal., J. Acoust. Soc. Am. 92, 2431 (A) (1992)]. POPE can include realistic sound-speed profiles and ground impedance. Predictions based upon the POPE have been compared to measurements at the JAPE 91 (Joint Acoustic Propagation Experiment) terrain masking experiment at White Sands Missile Range, New Mexico during the period 27–28 July 1991. The sound sources were hovering helicopters at the base of a hill and far away from the hill. In the JAPE data, the relative sound pressure level decreases rapidly from the top of the hill and becomes nearly constant along the base of the hill. This characteristic feature is well predicted by the polar parabolic equation calculations. POPE method appears to be an accurate means for predicting sound propagation over realistic terrain.
Calculation of average turbulence effects on sound propagation based on a fast field program formulation
Authors: Raspet Richard , Wu Wenliang
Published: October 2005

Daigle has published a series of papers in which he has applied the turbulent scattering theories of Chernov and Karavainikov to sound propagation over hard and finite impedance grounds. In these papers, Daigle has introduced the decorrelation in phase and amplitude due to turbulence along the direct and reflected path into the spherical wave reflection analysis for a nonrefracting atmosphere. The phase and amplitude decorrelation terms have been incorporated into the evaluation of the spectral integral of a fast field program for propagation in a refracting atmosphere. Although the calculation involves two significant approximations it reproduces Daigle’s results for homogeneous atmospheres and compares well with the upward refraction measurement of Parkin and Scholes and with measurements taken under a variety of refractive conditions at Bondville, Illinois by the U.S. Army Construction Engineering Research Laboratory.
Repulsion of phase-velocity dispersion curves and the nature of plate vibrations
Authors: Hosten B. , Deschamps M. , Gérard A. , Überall H.
Published: October 2005

The Lamb waves propagating in an elastic plate invacuo generate compressional (L) and shear type (T) plate vibrations that are coupled due to the boundary conditions. Without such coupling, their phase-velocity dispersion curves would form two intersecting families, which at high frequency tend towards the elastic-wave speeds CL and CT, respectively. It is shown that the coupling causes a repulsion of the dispersion curves, similar to that encountered in atomic physics for the energy levels of atoms combining into molecules, which prevents their intersection and at the same time exchanges the nature (L↔T) of the underlying vibrations. However, in the repulsion regions a succession of dispersion curves combines to asymptotically approach the uncoupled L or T dispersion curves, respectively. For the case of a plate bounded by fluid on one side, and vacuum on the other, the dispersion curves of the fluid-borne (Stoneley–Scholte type) wave, which is known from the studies of Grabovska and Talmant to be present in this case, and of the usual A0 Lamb wave exhibit a similar repulsion phenomenon.
Low-frequency noise-induced vibration of housing structures
Authors: Brooks Bennett M.
Published: October 2005

It is known that moderate levels of very low-frequency noise (less than 20 Hz) can induce vibration in elements of common residual housing structures. Measurements of low-frequency noise caused by nearby large industrial facilities were made at several different types of houses. These data are compared to criteria for the perceptibility of noise-induced vibration. The subjective perception by residents of house vibration, and the independent observations of others, correlate well with the noise criteria. In addition, measurements of house vibration were made at some test locations and are compared to both noise and vibration criteria.
Dispersive pulse propagation and group velocity
Authors: Bradley Charles E.
Published: October 2005

The propagation of pulses in a dissipative medium is investigated both theoretically and experimentally. The theoretical work is based on the dissipative dispersion integral, and the measurements are made in an air-filled periodic waveguide (i.e., the dispersion is Bloch wave dispersion). The dispersion integral is considered in the context of a sequence of characteristic pulse duration distances. The pulse propagates without distortion up to the smallest characteristic distance, and thereafter undergoes a new variety of distortion as it encounters each subsequent characteristic distance. Several new solutions of the dispersion integral that exhibit a variety of novel propagation properties are found. Pulses that shift in frequency as they propagate, accelerate as they propagate, and propagate at near-infinite group velocity are found analytically and verified experimentally. [Work supported by ONR.]
A dynamic model for the temporal properties of Swedish
Authors: Lyberg Bertil , Ekholm Barbro
Published: October 2005

The segment duration varies depending on a number of linguistic and nonlinguistic factors. At the word and phrase levels, the segment duration is found to vary depending on the position in the work and in the phrase. The positional effects on segment duration have been studied by several investigators and, for some languages, models have been hypothesized in order to describe the duration of speech segments in different positions in words and phrases. The greatest positional effect is the phenomenon of final lengthening that appears to be of considerable generality as a phonetic phenomenon. Most computational models for segment duration are, however, static, i.e., the durational properties are modeled at a certain speech rate. In this investigation the segment duration is studied at different speech rate and with focus assignment systematically varied along the sentence. The segment duration values are studied by means of both reiteratant speech and ordinary read speech. A tentative dynamic model for the segment duration is presented.
Intelligibility of Mandarin speakers of English: Correlation of acoustic and perceptual measures
Authors: Wardrip-Fruin C. , Constantinou A.
Published: October 2005

Wave duration and wave peak amplitude were measured for 10 Mandarin speakers of English and five native English speakers. Results revealed significant differences between the two groups on these acoustic variables. Discriminant function analysis resulted in 12 (80%) of 15 subjects being classified correctly in their respective language groups based on the wave duration and wave peak amplitude measures. A second experiment, with the 10 Mandarin subjects as speakers and 231 native English speakers as listeners, ranked the intelligibility of each speaker. A regression analysis revealed high correlation (r=0.897) between acoustic and perceptual measures; measurements of amplitude wave duration account for 89.1% of the variation in intelligibility and measurements of peaks in wave amplitude account for 68.5% of the variation in the speech samples. These findings suggest that intelligibility of Mandarin speakers of English is a function of acoustic parameters of prosody.
Final stop devoicing in Polish: Incomplete neutralization
Authors: Tieszen Bożena , Read Charles
Published: October 2005

In Polish, as in some other Slavic and Germanic languages, word-final obstruents are devoiced. Three monolingual speakers in Krakow recorded a sample of ine minimal pairs containing final /p,t,k,b,d,g/ preceded by each of the vowels /i,a,u/ in a meaningful carrier sentences. Each word was followed by a voiceless obstruent, in one case, and by a vowel in another. The speakers had also recorded some of the same words in the same environments in a narrative passage. Three durations were measured: Of the preceding vowel, of the stop closure, and of glottal pulsing into the closure. For all three speakers and all environments, the durations of the preceding vowel and of the stop closure did not differ significantly between underlyingly voiced and underlyingly voiceless stops. However, for all three speakers and all three places of articulation, glottal pulsing into the closure was significantly longer for underlyingly voiced stops than for their underlyingly voiceless counterparts. This outcome held for the words in the narrative passage as well as those in the carrier sentences. These results contrast with those obtained by Slowiaczek and Dinnsen [J. Phon. 13, 325–341 (1985)].