bluuebunny/crossref_metadata_2025 huggingface dataset:
Observables and prediction modeling in the presence of ultra-wideband heterogeneity
Authors: McCoy John J.
Published: October 2013

Underlying virtually all propagation and scattering models is an intuitive understanding; the acoustic field is observable using a device of a sufficiently small size to obtain a sufficiently dense set of discrete measurements. This assumes the field variation cuts off at an inner length scale larger than the device size, assuring that no information is lost to the inherent spatial averaging in any measurement. This understanding is faulty in the presence of environment heterogeneity observed on an extreme range of length scales. The reason is that all physical devices have finite accuracy, which limits their ability to capture variation on scales significantly larger than their size, in the presence of variation on intermediate scales. A more refined understanding of the ability to observe a field requires multiple devices, an unbounded hierarchy in the limit, to obtain multiple dense sets of discrete ‘‘observables.’’ This, then, suggests a different class of prediction models for environments with ultra-wideband heterogeneity, expressed in multiple sets of discrete variables, each set describing field variation in a limited subband. A framework for formulating these prediction models and their application to a scenario for which environment heterogeneity has no inner scale cutoff is presented.
Sound propagation in the mixtures of liquid and solid aggregate; similarities at micro- and nanoscales.
Authors: Tavossi Hasson M.
Published: October 2013

Sound propagation phenomena in certain liquid and solid aggregate mixtures, at micrometer scales, in some cases resemble the wave propagation behaviors of materials observed at nanometer and atomic scales. For example, it can be shown that the sound wave dispersion, attenuation, and cutoff-frequency effects depend on the same structural parameters as those observed at nano or atomic levels and are similar at both scales. Therefore, to investigate theoretical models of wave and matter interactions it is more convenient to use, as experimental tools, the readily analyzable models of wave propagation, in mixtures of solid and liquid, constructed at micrometer scales. Theoretical findings on sound propagation in the mixtures of liquid and solid particles at micrometer scales will be discussed. These results show the resemblance to the behavior of acoustic phonons, the lattice thermal vibrations of crystalline structures, at radically different scales. Experimental data on wave dispersion, attenuation, band-pass, and cutoff frequency effects, measured for sound propagation, in inhomogeneous materials consisting of mixtures of solid and liquid will be presented, showing the similarities of wave propagation behaviors at micro- and nanoscales.
Measurements of the attenuation and sound speed in bubbly salt water
Authors: Orris Gregory J. , Dacol Dalcio K. , Nicholas Michael
Published: October 2013

Bubble clouds were injected from below the surface of a 144-cubic-meter water tank, wherein hydrophones were placed at varying distances from an acoustic source. Measurements were made over a wide range of frequencies to verify and validate the theoretical predictions of the relevant dispersion formula. This work was undertaken under a variety of conditions by varying the relevant environmental parameters: void fraction, temperature, and salinity. Void fractions were varied from roughly 0.02% to 0.1%. Temperatures ranged from 9°C to 18°C, and the salinity was varied from zero to approximately 10% of typical oceanic values. Particular attention was paid to tracking the phase of the transmitted signal as the frequency progressed toward resonance starting from 100 kHz. This yielded phase-speed measurements in an essentially free-field environment using a modified version of phase spectral analysis. Time-of-flight measurements gave signal velocities, while the received energy yielded the attenuation. Results are compared to theoretical calculations, leading to the conclusion that current theoretical dispersion formula requires modification. [This work supported by the ONR.]
Models for acoustic scattering in high contrast media
Authors: Denis Max , Thompson Charles , Chandra Kavitha
Published: October 2013

In this work a numerical method for evaluating backscatter from a three-dimensional medium having high acoustic contrast is presented. The solution is sought in terms of a perturbation expansion in the contrast amplitude. It is shown that limitations of the regular perturbation expansion can be overcome by recasting the perturbation sequence as a rational fraction using Padé approximants. The resulting solution allows for an accurate representation of the pressure and allows for the poles in the frequency response to be modeled. The determination of the pulse-echo response for a high-contrast medium is discussed and presented.
Multiple scattering and visco-thermal effects
Authors: Duclos Aroune , Lafarge Denis , Pagneux Vincent , Cortis Andrea
Published: October 2013

For modeling sound propagation in a rigid-framed fluid-saturated porous material it is customary to use frequency-dependent density and compressibility functions. These functions, which describe ‘‘temporal’’ dispersion effects due to inertial/viscous and thermal effects, can be computed by FEM in simple geometries and give complete information about the long-wavelength properties of the medium. When the wavelength is reduced, new effects due to scattering must be considered. To study this, we consider solving the sound propagation problem in a 2-D ‘‘phononic crystal’’ made of an infinite square lattice of solid cylinders embedded in a fluid. An exact multiple-scattering solution is first developed for an ideal saturating fluid and then generalized to the case of visco-thermal fluid, by using the concept of visco-thermal admittances. The condition to use this concept is that the viscous and thermal penetration depths are small compared to the cylinder radius. We validate our results in the long-wavelength regime by direct comparisons with FEM data [A. Cortis, ‘‘Dynamic parameters of porous media,’’ Ph.D. dissertation (Delft U.P., Delft, (2002)]. When frequency increases, differences appear between the long-wavelength solution and the exact multiple-scattering solution, which could be interpreted in terms of ‘‘spatial’’ dispersion effects.
Modeling quasi-one-dimensional sound propagation in ducts having two propagation media using a cross-sectional averaging theory
Authors: Bliss Donald , Burton Lisa
Published: October 2013

Sound propagation of quasi-one-dimensional waves through a uniform duct partially filled with porous material has been studied theoretically and experimentally. The porous material makes the effective propagation wave number in the duct complex. A fairly simple theory based on cross-sectional averaging is derived and tested and found to work extremely well up to fairly high frequency. Interestingly, the basic theory depends only on the ratio of cross-sectional areas and the properties of the individual propagation media, but not on the specific configuration of material in a cross section. A higher order correction is developed to achieve excellent accuracy to very high frequency. This correction includes a coefficient that does depend on the specific cross-sectional configuration. Results are compared to exact solutions for layered and annular configurations, and also to experimental measurements with open cell foam as the porous material. An interesting application is to use measured wave numbers to predict the complex effective density and sound speed of porous media samples partially filling the duct. Other applications include fairly simple improved predictions of the behavior of sound in ducts lined with, or partially filled with, bulk reacting absorbing material.
Time characteristics of distortion product otoacoustic emissions recovery function after moderate sound exposure
Authors: Aranda de Toro Miguel Angel , Ordoñez Rodrigo , Hammersho/i Dorte
Published: October 2013

Exposure to sound of moderate level temporarily attenuates the amplitude of distortion product otoacoustic emissions (DPOAEs). These changes are similar to the changes observed in absolute hearing thresholds after similar sound exposures. To be able to assess changes over time across a broad frequency range, a detailed model of the recovery time characteristics is necessary. In the present study, the methodological aspects needed in order to monitor changes in DPOAEs from human subjects measured with high time resolution are presented. The issues treated are (1) time resolution of the measurements, (2) number of frequency points required, and (3) effects in fine structures, are they affected with the exposure? [Work supported by the Danish Research Council for Technology and Production.]
Musical expertise and concurrent sound segregation
Authors: Zendel Benjamin Rich , Alain Claude
Published: October 2013

There is growing evidence suggesting that musical training can improve performance in various auditory perceptual tasks. These improvements can be paralleled by changes in scalp recorded auditory evoked potentials (AEPs). The present study examined whether musical training modulates the ability to segregate concurrent auditory objects using behavioral measures and AEPs. Expert musicians and nonmusicians were presented with complex sounds comprised of six harmonics (220, 440, 660 Hz, etc.). The third harmonic was either tuned or mistuned by 1%–16% of its original value. Mistuning a component of a harmonic complex results in the precept of a second auditory object. Stimuli were presented passively (no response) and actively (participants responded by indicating if they heard one sound or two sounds). Behaviorally both musicians and nonmusicians perceived a second auditory object at similar levels of mistuning. In both groups, complex sounds generated N1 and P2 waves at fronto-central scalp regions. The perception of concurrent auditory objects was paralleled by an increased negativity around 150 ms post-stimulus onset. This increased negativity is referred to as object-related negativity (ORN). Small differences between musicians and nonmusicians were noted in the ORN. The implication of these results will be discussed in terms of current auditory scene analysis theory.
Analytical model for flow-excited interior cavity resonance and its application to the Stratospheric Observatory for Infrared Astronomy (SOFIA)
Authors: Ginsberg Jerry H.
Published: October 2013

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint effort between NASA and the German Space Agency that has installed a 20000-kg telescope in a modified 747-SP. The modifications entailed constructing bulkheads, one of which is used to provide the active mount for the telescope, and a door that rotates to open as much as one-quarter of the fuselage circumference to the atmosphere. This configuration represents a large compartment that can exhibit acoustic resonances at low frequencies. Concern arose that a Rossiter mode, which is an aerodynamic resonance in which vortices shed from the leading edge of a gap form a coherent standing pattern at certain speeds, would create a strong acoustic source for acoustic and structural modes, whose frequencies might coincide. A model consisting of a two-dimensional hard-walled waveguide having a Rossiter mode source and an elastic plate at one end was analyzed in order to understand these issues. Unlike conventional analyses of interior cabin noise, in which vibrating walls are the acoustic source, the elastic plate represents a compliant boundary that couples with the acoustic modes. The results lead to some general insights to the the possibility of a ‘‘triple resonance,’’ as well as the role of structural compliance for cavities that are excited by turbulent external flows.
Modeling airborne interior noise in full vehicles using statistical energy analysis
Authors: Charpentier Arnaud , Shorter Phil
Published: October 2013

SEA is particularly well suited for predicting airborne noise in vehicles. The acoustic sources found in such environment are typically spatially distributed around the vehicle and can be well represented with SEA diffuse acoustic loads. Multiple transmission paths contribute to interior noise levels including (1) mass law transmission through trimmed panels, (2) resonant radiation from vibrating structures, and (3) flanking paths through gaskets, seals, and holes. All these transmission mechanisms may be modeled using SEA techniques. Finally, interior trim (including carpet, headliner, seats) is a key contributor to the acoustic performance of modern vehicles. The vehicle sound package has a significant impact on both the strength of the transmissions paths into the vehicle as well as the acoustic absorption in the cabin. Both these effects can be accounted for with SEA through detailed models of the trim. SEA models of full vehicles are usually validated against experimental results at both component and system levels. The models can then be confidently used to (a) rank key design parameters governing interior levels and (b) quickly evaluate the impact of potential design changes. Example vehicle models and correlation results are presented here.
Some effect of trim and body panels on the low-frequency interior noise in vehicles
Authors: Pietrzyk Andrzej
Published: October 2013

Structure borne noise dominates the interior noise in vehicles at low frequencies. One of the basic vinroacoustic characteristics of the trimmed body is the noise transfer function, i.e., the acoustic response at a selected position in the passenger compartment, e.g., driver’s ear due to a mechanical excitation at a selected body mount. Detailed CAE models based on the FE method are today available for calculating this characteristic at low frequencies, corresponding to the engine idling and road excitation. However, the accuracy of CAE predictions of interior noise is still considered insufficient for the so-called analytical sign off, i.e., zero-prototypes vision. The current paper describes some investigations into the contribution of individual body panels to the overall interior noise. Also, the effect of selected interior trim items on the area investigated. Relative errors of prediction at different trim levels and different frequency ranges are discussed. Both experimental and CAE results are provided. The aim is to better understand the way the interior noise in vehicles is created, and how it can be controlled.
The dynamic response of a plate subjected to various edge excitations
Authors: Karp Baruch
Published: October 2013

Plane strain response of a semi-infinite, elastic plate to harmonic edge excitation is investigated analytically. The exact solution to this problem is obtained as a series expansion of the Rayleigh-Lamb modes of the plate. The variation of energy partition among the propagating modes with frequency of the edge excitation was found for load and displacement (symmetrical) perturbations of uniform and cosine form. The biorthogonality relation was employed in deriving the relative amplitudes of each mode to the given perturbation. The emphasis here is on the sensitivity of the far-field response, represented by propagating waves, to the details of the excitation. Within the frequency range investigated it was found that the plate’s response is remarkably insensitive to whether the excitation is load or displacement type. The two types of edge excitation distributions, on the other hand, result in different patterns of energy partition above the first cutoff frequency with similar energy partition only within limited range of frequencies. The effect of the nature of the excitation on the dynamic response of the plate and a possible implication to dynamic equivalence is discussed.
Modeling of acoustic and elastic wave phenomena using plane wave basis functions
Authors: Huttunen Tomi , Kaipio Jari P. , Monk Peter
Published: October 2013

When simulating acoustic, elastodynamic, or coupled fluid-solid vibration problems using standard finite element (FE) techniques, several elements per wavelength are needed to obtain a tolerable accuracy for engineering purposes. At high wave numbers, the requirement of dense meshes may lead to an overwhelmingly large computational burden, which significantly limits the feasibility of FE methods for the modeling of wave phenomena. A promising technique for reducing the computational complexity is to use plane wave basis functions opposed to the low-order polynomials that are used in conventional FE methods. A possible method for utilizing the plane wave basis is the ultra-weak variational formulation (UWVF). The UWVF method can be used for acoustic Helmholtz problems, elastodynamic Navier problems, or fluid-solid systems characterized by a coupled Helmholtz-Navier model. A comparison of the UWVF technique with a low-order FE method shows reduced computational complexity and improved accuracy.
Application of vibration energy flow to evaluation of thickness
Authors: Higashi Akihiko
Published: October 2013

In this study, the possibility of the useful application of the vibration energy flow is investigated. The vibration energy flow means the propagation of the vibration energy of the flexural waves. The vibration energy flow is expressed by the structural intensity. Here, it is easy to input the flexural waves in the thin plates and beam elements. Then, large structures such as ships use many of these thin plates and beam elements. But the usual methods of the evaluation and the inspection of these large structures are inefficient. Then, we investigated the possibility of the evaluation of the changed thickness of the structure by using the vibration energy flow analysis. As the result of analysis, the structural intensity suddenly changes at the position of the changed thickness. The changed quantity of the structural intensity corresponds to the change quantity of the thickness. Then, the evaluation method of the thickness of the structure is proposed. As a result, it was found that the change of the structural intensity indicates the change of the thickness. And the evaluation of the change of thickness of beams could be possible by using the proposed method.
Cross-language perception of voice and affect
Authors: Gobl Christer , Yanushevskaya Irena , Chasaide Ailbhe N.
Published: October 2013

The paper reports on a cross-language study of how voice quality and f0 combine in the signaling of affect. Speakers of Irish-English and Japanese participated in perception tests. The stimuli consisted of a short utterance where f0 and voice source parameters were varied using the LF-model implementation of the KLSyn88a formant synthesizer, and were of three types: (1) VQ only involving voice quality variations and a neutral f0 contour; (2) f0 only, with different affect-related f0 contours and modal voice; (3) VQ+f0 stimuli, where the voice qualities of (1) combine with specific f0 contours from (2). Overall, stimuli involving voice quality variation were consistently associated with affect. In (2) only stimuli with high f0 yielded high affective ratings. Striking differences emerge between the ratings obtained from the two language groups. The results show that not only were some affects consistently perceived by one language group and not the other, but also that specific voice qualities and pitch contours were associated with very different affects across the two groups. The results have important implications for expressive speech synthesis, indicating that language/culture-specific differences need to be considered. [This work is supported by the EU-funded Network of Excellence on Emotion, HUMAINE.]
An articulatory study of coronal consonants in Arrernte
Authors: Tabain Marija , Beare Richard , Best Catherine , Goldstein Louis
Published: October 2013

This paper presents electro-magnetic articulography (EMA) data on the four coronal stops of Arrernte, an Australian language. The stops are: the lamino-dental ‘‘th,’’ the apico-alveolar ‘‘t,’’ the apico-postalveolar (or ‘‘retroflex’’) ‘‘rt,’’ and the lamino-palatal ‘‘ty.’’ Jaw, tongue tip (TT), and tongue body (TB) data were collected for two female speakers of the language. Results for the first speaker show a fronted tongue position for the laminal consonants, with the TT reflecting a similar location for both the dental and the palatal. However, for the palatal, the TB position is much higher, whereas for the dental, the TB is very low. For the apical consonants, the TT is not as far forward, and the TB is not quite as high as for the lamino-palatal. For both TT and TB, apico-postalveolar is further back than apico-alveolar. For the second speaker, the TT sensor failed, but in line with the first speaker, the TB sensor showed a higher position for the palatal. The other stops were lower and more forward, with the postalveolar TB position higher than the laminal or alveolar stop position. For both speakers, the jaw position is lowest for the postalveolar. [Work supported by Australian Research Council and NIH: NIDCD.]
Acoustic phonetic variability and auditory word recognition by dyslexic and nondyslexic children
Authors: Keating Patricia , Nielsen Kuniko , Manis Frank , Bruno Jennifer
Published: October 2013

The hypothesis that dyslexia involves degraded phonological representations predicts impairments in behaviors that rely on these representations, such as auditory word recognition. Normal adult listeners recognize different pronunciations of a word as instances of the same lexical item, but more slowly and less accurately; dylexics should be even more impaired by acoustic phonetic variability. Children with and without dyslexia performed a word recognition task: on each trial, a child hears a target word, then eight probes (matching the target or not), responding yes/no to each probe. On some trials, probes are spoken by multiple talkers who differ in age, sex, speech style, etc.; on some trials the match probes also differ from the target in final stop consonant allophone. Responses are scored for accuracy and speed. Research questions include: Do all children demonstrate less accurate/slower recognition of words spoken by multiple talkers versus by one talker? Do all children demonstrate less accurate/slower recognition of words spoken with different allophones? Do dyslexic children demonstrate less accurate/slower recognition than nondyslexic children and, if so, for all trials, only for multiple talker trials, and/or only for different allophone trials; for all dyslexic children, or only those with particular phonological impairments? [Work supported by NIH.]
A cross-linguistic study of informational masking: English versus Chinese
Authors: Schneider Bruce A. , Li Liang , Daneman Meredyth , Wu Xihong , Yang Zhigang , Chen Jing , Huang Ying
Published: October 2013

The amount of release from informational masking in monolingual English (Toronto, Canada), and Chinese (Beijing, China) listeners was measured using the paradigm developed by Freyman et al. [J. Acoust. Soc. Am. 106, 3578–3588]. Specifically, psychometric functions relating percent-correct word recognition to signal-to-noise ratio were determined under two conditions: (1) masker and target perceived as originating from the same position in space; (2) masker and target perceived as originating from different locations. The amount of release from masking due to spatial separation was the same for English and Chinese listeners when the masker was speech-spectrum noise or cross linguistic (Chinese speech masking English target sentences for English listeners or English speech masking Chinese target sentences for Chinese listeners). However, there was a greater release from masking for same-language masking of English (English speech masking English target sentences) than for same-language masking of Chinese (Chinese speech masking Chinese target sentences). It will be argued that the differences in same-language masking between English and Chinese listeners reflect structural differences between English and Mandarin Chinese. [Work supported by China NSF and CIHR.]
Neural coding of perceptual interference at the preattentive level
Authors: Zhang Yang , Kuhl Patricia , Imada Toshiaki , Imada Toshiaki , Kawakatsu Masaki
Published: October 2013

Language acquisition involves neural commitment to language-specific auditory patterns, which may interfere with second language learning. This magnetoencephalography study tested whether perceptual interference could occur at the preattentive level. Auditory mismatch field (MMF) responses were recorded from ten American and ten Japanese adult subjects in the passive oddball paradigm. The subjects read self-chosen books and ignored the sounds. Three pairs of synthetic /ra-la/ syllables were used: one cross-category pair varied only in the third formant (F3), and the other two within-category pairs varied only in the second formant (F2). ANOVA results showed a main effect of acoustic dimension with significant interaction with subject groups (p<0.01). As reported earlier, American listeners showed larger but later MMF responses for the F3 change. By contrast, Japanese listeners showed larger and earlier MMFs than Americans for changes in F2. Moreover, Japanese listeners had larger and earlier MMF responses for the changes in F2 as against changes in F3, which was more prominent in the right hemisphere than in the left. These results provided further support for the hypothesis that language experience produces neural networks dedicated to the statistical properties of incoming speech experienced in infancy, which later interfere with second language acquisition.
Nondurational cues for durational contrast in Japanese
Authors: Idemaru Kaori , Guion Susan G
Published: October 2013

This study explores potential secondary cues to a durational contrast by examining short and long stop consonants in Japanese. Durational contrasts are susceptible to considerable variability in temporal dimensions caused by changes in speaking rate. In this study, the proposal is examined that multiple acoustic features covary with the stop length distinction and that these features may aid in accessing the percept intended by the speaker, even when the primary cue, closure duration, is unreliable. The results support the proposal, revealing the presence of multiple acoustic features covarying with the short versus long contrast. Not only are there durational correlates to this contrast—the preceding vowel is longer and the following vowel is shorter for geminates than singletons—but there also are nondurational features covarying with this contrast. Greater fundamental frequency and intensity drops are found from the preceding to the following vowel for the geminate than the singleton stops. These results suggest the possibility that systematic variation of these acoustic features is used in the perceptual categorization of the contrast in addition to the primary cue of closure duration. Moreover, the nondurational correlates are promising candidates for speech-rate resistant features.
Different motor strategies for increasing speaking rate: Data and modeling
Authors: Zandipour Majid , Perkell Joseph , Tiede Mark , Guenther Frank , Honda Kiyoshi , Murano Emi
Published: October 2013

Different motor strategies for increasing speaking rate: data and modeling EMG, kinematic and acoustic signals were recorded from two male subjects as they pronounced multiple repetitions of simple nonsense utterances. The resulting data indicate that the two subjects employed different motor strategies to increase speaking rate. When speaking faster, S1 significantly increased the size of the articulatory target region for his tongue movements, increased the speed of the tongue movements and the rate of EMG rise somewhat, while decreasing the movement duration significantly and movement distance slightly. In contrast, at the fast rate, S2 had the same size articulatory target region and rate of EMG rise as at the normal rate, but decreased the speed, distance, and duration of tongue movement slightly. Each subject had similar dispersions of acoustic targets in F1–F2 space at fast versus normal rates, but both shifted target centroids toward the center of the vowel space at the fast rate. Simulations with a biomechanical model of the vocal tract show how modulations of motor commands may account for such effects of speaking rate on EMG, kinematics, and acoustic outputs. [Work supported by NIDCD, NIH.]
The rhythmic characterization of two varieties of Portuguese
Authors: Stockmal Verna , Alonso Marks Emilia , Woods Audra , Bond Z. S.
Published: October 2013

As spoken in Europe, Portuguese is said to be stress-timed, while Brazilian Portuguese appears to display characteristics of both stress and syllable timing [P. A. Barbosa, D.E.L.T.A. 16, 369–402 (2000)]. We employed the Ramus et al. metric, based on acoustic-phonetic measurements [Ramus et al., Cognition 73, 265–292 (1999)], to investigate the possibility of distinguishing between the two varieties of the language. Five native speakers of European Portuguese and five native speakers of Brazilian Portuguese recorded the same short prose passage taken from a magazine. The talkers were asked to read at a normal, comfortable rate. The reading time of the passage averaged 60 s, with considerable differences among the talkers. From the vocalic and consonantal intervals, the Ramus metrics, percent vocalic interval and standard deviation of consonantal and vocalic interval, were calculated. The five talkers of the two language varieties differed on the values of these parameters. The values of %V and SD-V showed overlap between the two talker groups, while the BP talkers tended to show lower values for SD-C. Apparently, the rhythmic characterization of the two varieties of the language is not clearly categorical, but rather ranges along a continuum.
Indexical cues to talker sex and individual talker identity extracted from vowels produced in sentence-length utterances
Authors: Berkowitz Michael J. , Bachorowski Jo-Anne , Owren Michael J.
Published: October 2013

The purpose of this study was to replicate and extend a previous study of indexical cuing [J.-A. Bachorowski and M. J. Owren, J. Acoust. Soc. Am. 106, 1054–1063 (1999)] by including more vowel sounds spoken in more diverse contexts. Specific combinations of acoustic parameters that should represent talker sex and individual talker identity were identified using predictions based on known sources of variation in vocal production-related anatomy. This study utilized 100 recordings of sentence-length utterances, produced by each of 43 male and 44 female undergraduates, as well as 22 stock-phrase recordings produced by these same participants. One of five vowel sounds (/æ, ε, i, ■, u/) was isolated from each sentence and analyzed for F0, F1, F2, F3, F4, vowel duration, jitter, shimmer, and harmonicity. Classification by talker sex was nearly perfect using a combination of cues related to both vocal-fold and vocal-tract anatomy. The accuracy of classification by individual identity depended strongly on cues relating to vocal tract-variation within sex.
Utterance-final position and projection of femininity in Japanese
Authors: Hiramoto Mie , Anderson Victoria
Published: October 2013

Japanese female speakers frequent use of suprasegmental features such as higher pitch, longer duration, wider pitch range, and more instances of rising intonation vis-a-vis male speakers, is recognized as Japanese womens language (JWL) prosody. However, these features normally co-occur with gender-specific sentence-final particles (SFPs) like the strongly feminine ‘‘kashira.’’ In this study, we examined the use of pitch and duration in utterances without SFPs, to determine whether JWL prosody is a function of SFPs or of utterance-final position. Eight male and eight female native Japanese speakers were instructed to read prepared sentences as though auditioning for a masculine theater role and then as though auditioning for a feminine role. Results indicate that utterance-final position is the projection point of JWL prosody even in the absence of SFPs. The data used for this study show high pitch, wide pitch range, long duration, and rising intonation at utterance-final positions when produced (by both men and women) in the feminine gender role. Conversely, in the masculine gender role, both men and women avoid the use of such prosodic features, and may even avoid using rising intonation in interrogative sentences, where the tonal grammar calls for it.
Vowel devoicing in Japanese infant- and adult-directed speech
Authors: Fais Laurel , Werker Janet , Kajikawa Sachiyo , Amano Shigeaki
Published: October 2013

It is well known that parents make systematic changes in the way they speak to infants; they use higher pitch overall, more pronounced pitch contours, more extreme point vowels, and simplified morphology and syntax (Andruski and Kuhl, 1996; Fernald et al., 1989). Yet, they also preserve information crucial to the infants ability to acquire the phonology of the native language (e.g., phonemic length information, Werker et al., 2006). The question examined in this paper is whether information other than phonemic segmental information is also preserved, namely, information concerning the phonological process of vowel devoicing. Devoicing of high vowels between voiceless consonants and word-finally after a voiceless consonant is a regular and well-attested phonological process in Japanese (Shibatani, 1990). A corpus of speech by Japanese mothers addressed to their infants and addressed to another adult was examined, and the degree and frequency with which they apply vowel devoicing in each type of speech was analyzed. Rates of vowel devoicing in speech to adults and infants are compared, accommodations made to infants and to hearing-impaired children are discussed (Imaizumi et al., 1995), and the implications of these accommodations for the acquisition of vowel devoicing by Japanese infants are explored.
An acoustic study of laringeal contrast in three American Indian Languages
Authors: Avelino Heriberto
Published: October 2013

A contrast between modal and nonmodal phonation is commonly found in American Indian languages. The use of laryngealized voice has been reported in a number of languages from different linguistic families. This paper investigates the acoustics of laryngealized phonation in three indigenous languages spoken in Mexico, Yalalag Zapotec, Yucatec Maya, and Mixe. These languages differ in terms of the use of other features controlled by action of the larynx, i.e., tone. In Zapotec there is a contrast between high, low, and falling tones; Maya has phonemic high and low tones, whereas Mixe does not present phonemic pitch. The results show that the production of phonemic laryngeal vowels differs from language to language. The data suggest that the specific implementation of laryngealization depends in part on the relationship with contrastive tone. The patterns of the languages investigated provide new evidence of the possible synchronization of phonation throughout the vowel. With this evidence, a typology of modal/nonmodal phonation in phonation-synchronizing languages is proposed.
Articulatory settings of French and English monolinguals and bilinguals
Authors: Wilson Ian L. , Gick Bryan
Published: October 2013

This study investigated articulatory setting (AS), a language’s underlying posture of the articulators. Interspeech posture (ISP) of the articulators (their position when motionless during interutterance pauses) was used as a measure of AS in Canadian English and Quebecois French. Optotrak and ultrasound imaging were used to test whether ISP is language specific in monolingual and bilingual speakers. Results show significant differences in ISP across the monolingual groups, with English exhibiting a higher tongue tip, more protruded upper and lower lips, and narrower horizontal lip aperture. Results also show that upper and lower lip protrusion are greater for the English ISP than for the French ISP, in all bilinguals who were perceived as native speakers of both languages, but in no other bilinguals. Tongue tip height results mirror those of the monolingual groups, for half of the bilinguals perceived as native speakers of both languages. Finally, results show that there is no unique bilingual-mode ISP, but instead one that is equivalent to the monolingual-mode ISP of a bilingual’s currently most-used language. This research empirically confirms centuries of noninstrumental evidence for AS, and for bilinguals it suggests that differences between monolingual and bilingual modes do not hold at the phonetic level.
Temporal and spectral variability of vowels within and across languages with small vowel inventories: Russian, Japanese, and Spanish
Authors: Law Franzo F. , Gilichinskaya Yana D. , Ito Kikuyo , Hisagi Miwako , Berkowitz Shari , Sperbeck Mieko N. , Monteleone Marisa , Strange Winifred
Published: October 2013

Variability of vowels in three languages with small vowel inventories (Russian, Japanese, and Spanish) was explored. Three male speakers of each language produced vowels in two-syllable nonsense words (VCa) in isolation and three-syllable nonsense words (gaC1VC2a) embedded within carrier sentences in three contexts: bilabial stops in normal rate sentences and alveolar stops in both normal and rapid rate sentences. Dependent variables were syllable duration and formant frequency at syllable midpoint. Results showed very little variation across consonant and rate conditions in formants for /i/ in Russian and Japanese. Japanese short /u, o, a/ showed fronting (F2 increases) in alveolar context, which was more pronounced in rapid sentences. Fronting of Japanese long vowels was less pronounced. Japanese long/short vowel ratios varied with speaking style (isolation versus sentences) and speaking rate. All Russian vowels except /i/ were fronted in alveolar context, but showed little change in either spectrum or duration with speaking rate. Spanish showed a strong effect of consonantal context: front vowels were backed in bilabial context and back vowels were fronted in alveolar context, also more pronounced in rapid sentences. Results will be compared to female productions of the same languages, as well as American English production patterns.
Does infant-directed speech in Tagalog resemble infant-directed speech in American English?
Authors: Garza-Prisby Emmylou , Katz-Gershon Shiri , Andruski Jean
Published: October 2013

This study compared the speech of a Filipino mother in infant- and adult-directed speech in order to investigate whether the mother used the acoustic features typically found in the infant-directed speech of American English-speaking mothers. Little acoustic documentation is available on the acoustic features of Tagalog, and no acoustic comparison of speech registers has so far been conducted. Impressionistically, Tagalog-speaking mothers’ do not appear to use the features typically found in American mothers speech to their young infants. The mother was recorded talking to her infant and to another adult native speaker of Tagalog. Recordings were made in the mother’s home and visits occurred during the first 6 months of the infant’s life. Specific acoustic features analyzed include (a) vowel duration, (b) vowel format frequencies, (c) vowel triangle size, (d) rate of speech, (e) fundamental frequency, and (f) F0 range. Morphological and syntactic features were also analyzed, including (g) mean length of utterance and (h) sentence length. Results support a need for further study of speech registers in Filipino mothers.
Distributed acoustic sensing in shallow water
Authors: Schmidt Henrik
Published: October 2013

The significance of Leonid Brekhovskikh to the ocean acoustics is undisputed. He was pioneering not only in terms of fundamental understanding of the ocean acoustic waveguide, but also the development of efficient and numerically stable approaches to propagation of sound in a stratified ocean. As such he has been an inspiration to a whole generation of model developers, leading to today’s suite of extremely powerful wave theory models, capable of accurately representing the complexity of the shallow-water ocean waveguide physics. The availability of these computational tools have in turn led to major advances in adaptive, model-based signal-processing techniques. However, such computationally intensive approaches are not necessarily optimal for the next generation of acoustic sensing systems. Thus, ocean observation in general is currently experiencing a paradigm shift away from platform-centric sensing concepts toward distributed sensing systems, made possible by recent advances in underwater robotics. In addition to a fully autonomous capability, the latency and limited bandwidth of underwater communication make on-board processing essential for such systems to be operationally feasible. In addition, the reduced sensing capability of the smaller physical apertures may be compensated by using mobility and artificial intelligence to dynamically adapt the sonar configuration to the environment and the tactical situation, and by exploiting multiplatform collaborative sensing. The development of such integrated sensing and control concepts for detection, classification, and localization requires extensive use of artificial intelligence incorporating a fundamental understanding of the ocean acoustic waveguide. No other sources in literature provide this with the clarity and depth that is the trademark of Academician Brekovskikh’s articles and classical textbooks. [Work supported by ONR.]
Measurement of the plane-wave reflection coefficient of the ocean bottom and the legacy of Leonid Brekhovskikh
Authors: Frisk George V. , Souza Luiz L.
Published: October 2013

Leonid Brekhovskikh’s classic text [Waves in Layered Media (Academic, New York, 1980)] inspired the development of several techniques for measuring the plane-wave reflection coefficient of the ocean bottom. Specifically, his application of the geometrical acoustics approximation to the problem of reflection of a spherical wave from a horizontally stratified medium provided the theoretical foundation for evaluating the strengths and weaknesses of various measurement methods. The most popular method assumes that the reflected field also consists of a spherical wave multiplied by the reflection coefficient evaluated at the specular angle. However, Brekhovskikh’s work showed that this interpretation is confined to a limited range of angles and bottom structures and, if applied improperly, can lead to unphysical results such as negative bottom loss. This paper describes a technique which circumvents these deficiencies. It consists of measuring the pressure field magnitude and phase versus range due to a cw point source and Hankel transforming these data to obtain the depth-dependent Green’s function versus horizontal wavenumber. The reflection coefficient is then obtained from the Green’s function using the analytical relationship between the two quantities. The method is demonstrated using 220-Hz data obtained in a near-bottom geometry in the Icelandic Basin. [Work supported by ONR.]
Plane-wave model and experimental measurements of the directivity of a Fabry-Perot, polymer film, ultrasound sensor
Authors: Cox Benjamin T. , Beard Paul C.
Published: October 2013

Optical detection of ultrasound is popular due to the small element sizes that can be achieved. One method exploits the thickness change of a Fabry-Perot (FP) interferometer caused by the passage of an acoustic wave to modulate a laser beam. This detection method can have greater sensitivity than piezoelectric detectors for sub-millimeter element sizes. The directivity of FP sensors and the smallest achievable effective element size are examined here. A plane-wave model of the frequency-dependent directional response of the sensor, based on Brekhovskikh’s work on elastic waves in layered media, is described and validated against experimental directivity measurements made over a frequency range of 15 MHz and from normal incidence to 80 deg. In terms of applications, the model may be used to provide a noise-free response function that can be deconvolved from sound field measurements in order to improve accuracy in high-frequency metrology and imaging applications, or, for example, as a predictive tool to improve sensor design. Here, the smallest achievable effective element radius was investigated by comparing the directivity with that of a rigid circular pressure transducer, and found to be ∼0.9d, where d is the thickness of the FP interferometer. [Funding was provided by the EPSRC, UK]
The interference head wave and its parametric dependence
Authors: Choi Jee Woong , Dahl Peter H.
Published: October 2013

The interference head wave that can exist in the presence of a sound-speed gradient in the sediment, is a precursor arrival representing a transition between the first-order head wave and the zeroth-order refracted wave. Using a parabolic equation (PE) simulation, Choi and Dahl [J. Acoust. Soc. Am. 119, 2660–2668 (2006)] showed how the small shift in the dominant frequency of the interference head wave behaves as a function of the nondimensional parameter zeta, which itself is a function of center frequency, gradient, and range. For example, it was shown that the maximum frequency shift occurring in the vicinity of zeta equals 2. In this work, we investigate the amplitude and additional spectral properties of the interference head wave and analyze the cause of the frequency shift phenomenon using the ray theory. The limitation on the application of ray method also will be discussed. Finally, the conclusion will be verified by the time-dependent simulation using the RAM PE algorithm. [Work supported by the ONR.]
Absorption of sound in seawater and ocean ambient noise, the scientific passions of Fred Fisher
Authors: Hildebrand John A.
Published: October 2013

Fred Fisher made seminal contributions to ocean acoustics in the understanding of the absorption of sound in seawater and ocean ambient noise. Laboratory data and long-range sound propagation data revealed excess acoustic absorption in seawater. Fred Fisher spent much of his scientific career, beginning with his Ph.D dissertation, teasing out the contributions of various seawater components to sound absorption, and his work on this topic set the standard for understanding and modeling these phenomena. Ambient noise is an important aspect of underwater signal detection and is the focus of recent concerns about disturbance of marine organisms. Fred Fisher made important contributions to ambient noise studies by conducting measurements of vertical directionality, thereby testing models for ambient noise production. The value of archival ambient noise data and recent increases in ambient noise will be discussed.
Fred Fisher’s high-pressure work with eyewash and epsom salts
Authors: de Moustier Christian
Published: October 2013

Starting in 1957 Fred Fisher led research programs devoted to high-pressure measurements related to the physical chemistry of sound absorption in seawater due to magnesium sulfate and other salts. As he put it, he spent his professional lifetime squeezing epsom salt. His interest in the low-frequency anomalous sound absorption in the ocean below 1 kHz led to the discovery of boric acid as the cause of the low-frequency relaxation. This paper is a short review of Fred Fisher’s contributions to our knowledge of sound absorption in seawater, based in part on his carefully hand-written lecture notes and numerous low-pressure discussions.