Read by QxMD icon Read

Journal of the Acoustical Society of America

Michelle R Kapolowicz, Vahid Montazeri, Peter F Assmann
To determine the effect of reduced spectral resolution on the intelligibility of foreign-accented speech, vocoder-processed sentences from native and Mandarin-accented English talkers were presented to listeners in single- and multiple-talker conditions. Reduced spectral resolution had little effect on native speech but lowered performance for foreign-accented speech, with a further decrease in multiple-talker conditions. Following the initial exposure, foreign-accented speech with reduced spectral resolution was less intelligible than unprocessed speech in both single- and multiple-talker conditions...
February 2018: Journal of the Acoustical Society of America
Youngjoo Suh, Hoirin Kim
The histogram equalization approach is an efficient feature normalization technique for noise robust automatic speech recognition. However, it suffers from performance degradation when some fundamental conditions are not satisfied in the test environment. To remedy these limitations of the original histogram equalization methods, class-based histogram equalization approach has been proposed. Although this approach showed substantial performance improvement under noise environments, it still suffers from performance degradation due to the overfitting problem when test data are insufficient...
February 2018: Journal of the Acoustical Society of America
Stephen C Conlon, Philip A Feurtado
Acoustic black holes (ABHs) have been explored and demonstrated to be effective passive treatments for broadband noise and vibration control. Performance metrics for assessing damping concepts are often focused on maximizing structural damping loss factors. Optimally performing damping treatments can reduce the resonant response of a driven system well below the direct field response. This results in a finite structure whose vibration input-output response follows that of an infinite structure. The vibration mobility transfer functions between locations on a structure can be used to assess the structure's vibration response phase, and compare its phase response characteristics to those of idealized systems...
February 2018: Journal of the Acoustical Society of America
Francesco Lanza di Scalea, Simone Sternini, Albert Y Liang
The focus of this paper is the estimation of the dynamic transfer function between two outputs of a linear system subjected to an uncontrolled and generally unknown excitation, and accounting for possible uncorrelated noise present at both outputs. Several applications of this case exist in the passive identification of dynamic systems including the health monitoring and/or non-destructive evaluation of structures subjected to natural "ambient" excitations. It is well known that noise-robust transfer function estimation of a single-input-single-output system can be achieved by a normalized cross-power spectrum operation...
February 2018: Journal of the Acoustical Society of America
Haesang Yang, Woojae Seong
Compressional wave speed and attenuation were measured for water-saturated granular media employing five kinds of glass beads having unimodal and bimodal grain size distributions. Glass beads with grain sizes ranging from 250 to 850  μm were used for the acoustic measurements at a frequency range from 350 kHz to 1.1 MHz, which includes the transition range where scattering and non-scattering losses co-exist. The compressional wave speed and attenuation data are presented as a function of frequency and grain size distribution...
February 2018: Journal of the Acoustical Society of America
J Berger, J-R Bidlot, M A Dzieciuch, W E Farrell, P F Worcester, R A Stephen
The ocean acoustic noise floor (observed when the overhead wind is low, ships are distant, and marine life silent) has been measured on an array extending up 987 m from 5048 m depth in the eastern North Pacific, in what is one of only a few recent measurements of the vertical noise distribution near the seafloor in the deep ocean. The floor is roughly independent of depth for 1-6 Hz, and the slope (∼ f-7 ) is consistent with Longuet-Higgins radiation from oppositely-directed surface waves. Above 6 Hz, the acoustic floor increases with frequency due to distant shipping before falling as ∼ f-2 from 40 to 800 Hz...
February 2018: Journal of the Acoustical Society of America
Pierre Lecomte, Philippe-Aubert Gauthier, Christophe Langrenne, Alain Berry, Alexandre Garcia
This paper investigates the compensation of room reflections based on Ambisonics. A multichannel room equalization method for Ambisonic playback systems is proposed. The compensation filters are designed to operate in the spherical harmonics domain, prior to the decoding step. Their design requires the inversion of a matrix which can be ill-conditioned at low frequencies and for higher Ambisonic orders. A crossover and cross-order method is proposed to circumvent this problem and to reduce the amount of necessary regularization...
February 2018: Journal of the Acoustical Society of America
Oleg A Godin, Alexander B Baynes
Anthropogenic noise pollution of the ocean is an acute and growing problem. This letter explores one possible mechanism of noise abatement. The far-field acoustic pressure due to a compact underwater source can be suppressed by placing a small compliant body in the vicinity of the source. Here, the feasibility and efficiency of the suppression are evaluated by quantifying the reduction in radiated acoustic energy for several simple geometries, which include sound sources in an unbounded fluid, near a reflecting boundary, or in a shallow-water waveguide...
February 2018: Journal of the Acoustical Society of America
Qipeng Feng, Feiran Yang, Jun Yang
A time-domain sound field reproduction (SFR) method based on the group Lasso (GL) is presented. The proposed method optimizes the positions and the number of active loudspeakers in the time domain by iteratively solving a mixed-norm constrained optimization problem. Simulation results demonstrate that the proposed method achieves accurate broadband SFR using a small number of active loudspeakers and significantly outperforms the least-squares method when the desired sound field is under-sampled. Moreover, the GL algorithm can also be used to optimize the loudspeaker placement for sound field control systems...
February 2018: Journal of the Acoustical Society of America
James Whang
High vowel devoicing in Japanese, where /i, u/ in a C1 VC2 sequence devoice when both C1 and C2 are voiceless, has been studied extensively, but factors that contribute to the devoiced vowels' likelihood of complete deletion is still debated. This study examines the effects of phonotactic predictability on the deletion of devoiced vowels. Native Tokyo Japanese speakers (N = 22) were recorded in a sound-attenuated booth reading sentences containing lexical stimuli. C1 of the stimuli were /k, ʃ/, after which either high vowel can occur, and /ʧ, ϕ, s, ç/, after which only one of the two occurs...
February 2018: Journal of the Acoustical Society of America
Jing Chen, Brian C J Moore, Thomas Baer, Xihong Wu
An algorithm for enhancing spectral changes over time was previously shown to improve the intelligibility of speech in steady speech-spectrum noise (SSN) for hearing-impaired subjects but tended to impair intelligibility for speech in a background of two-talker speech. Large individual differences were found and the application of a genetic algorithm for selecting the "best" parameter values for each listener was found to be beneficial. In the present study, the spectral-change enhancement (SCE) processing was modified by individually tailoring the degree of SCE based on the frequency-dependent hearing loss of the subjects, and by using finer frequency resolution...
February 2018: Journal of the Acoustical Society of America
Matthew L Willardson, Brian E Anderson, Sarah M Young, Michael H Denison, Brian D Patchett
Time reversal (TR) is a signal processing technique that can be used for intentional sound focusing. While it has been studied in room acoustics, the application of TR to produce a high amplitude focus of sound in a room has not yet been explored. The purpose of this study is to create a virtual source of spherical waves with TR that are of sufficient intensity to study nonlinear acoustic propagation. A parameterization study of deconvolution, one-bit, clipping, and decay compensation TR methods is performed to optimize high amplitude focusing and temporal signal focus quality...
February 2018: Journal of the Acoustical Society of America
Matthew J Goupell, Olga A Stakhovskaya
Accurate localization of complex sounds involves combining interaural information across frequencies to produce a single location percept. Interaural level differences (ILDs) are highly frequency dependent and it is unclear how the auditory system combines differing ILDs across frequency. Therefore, ILD just noticeable differences (JNDs) and intracranial lateralization were measured in young normal-hearing listeners using single- and multi-band stimuli. The bands were 300-ms, 10-Hz narrowband noises; the multi-band condition had three bands; they started and ended synchronously; they were located around three different frequency regions (750, 2000, or 4000 Hz); they had five different frequency separations that ranged from unresolved to resolved; the bands were dichotic with the same non-zero ILD (targets) or were diotic with zero ILD (interferers)...
February 2018: Journal of the Acoustical Society of America
Srikanta K Mishra, Milan Biswal, Anup Amatya
The medial olivocochlear efferent fibers control outer hair cell responses and inhibit the cochlear-amplifier gain. Measuring efferent function is both theoretically and clinically relevant. In humans, medial efferent inhibition can be assayed via otoacoustic emissions (OAEs). OAEs arise by two fundamentally different mechanisms-nonlinear distortion and coherent reflection. Distortion and reflection emissions are typically applied in isolation for studying the efferent inhibition. Such an approach inadvertently assumes that efferent-induced shifts in distortion and reflection emissions provide redundant information...
February 2018: Journal of the Acoustical Society of America
Brian Roberts, Robert J Summers
This study explored the extent to which informational masking of speech depends on the frequency region and number of extraneous formants in an interferer. Target formants-monotonized three-formant (F1+F2+F3) analogues of natural sentences-were presented monaurally, with target ear assigned randomly on each trial. Interferers were presented contralaterally. In experiment 1, single-formant interferers were created using the time-reversed F2 frequency contour and constant amplitude, root-mean-square (RMS)-matched to F2...
February 2018: Journal of the Acoustical Society of America
Michael B Muhlestein, Vladimir E Ostashev, D Keith Wilson, Donald G Albert
The propagation of acoustic pulses through a forest is considered. Multiple-scattering effects are accounted for by using the energy-based radiative transfer theory under a modified Born approximation, resulting in an expression for the diffuse intensity as a function of time and dominant frequency. While this expression is a complicated set of three integrals, certain practical approximations enable analytic evaluation of one, two, or even all three integrals. Any remaining integrals may be numerically calculated...
February 2018: Journal of the Acoustical Society of America
Nicolas Bochud, Jérôme Laurent, François Bruno, Daniel Royer, Claire Prada
A method to recover the elastic properties, thickness, or orientation of the principal symmetry axes of anisotropic plates is presented. This method relies on the measurements of multimode guided waves, which are launched and detected in arbitrary directions along the plate using a multi-element linear transducer array driven by a programmable electronic device. A model-based inverse problem solution is proposed to optimally recover the properties of interest. The main contribution consists in defining an objective function built from the dispersion equation, which allows accounting for higher-order modes without the need to pair each experimental data point to a specific guided mode...
February 2018: Journal of the Acoustical Society of America
Amanda Seidl, Françoise Brosseau-Lapré, Lisa Goffman
This project explored whether disruption of articulation during listening impacts subsequent speech production in 4-yr-olds with and without speech sound disorder (SSD). During novel word learning, typically-developing children showed effects of articulatory disruption as revealed by larger differences between two acoustic cues to a sound contrast, but children with SSD were unaffected by articulatory disruption. Findings suggest that, when typically developing 4-yr-olds experience an articulatory disruption during a listening task, the children's subsequent production is affected...
February 2018: Journal of the Acoustical Society of America
James D Lewis
This study examined the effect of the area discontinuity between the measurement-probe sound source and ear canal on the plane-wave approximation of power reflectance. The area discontinuity was hypothesized to introduce measurement-location sensitivity to the power reflectance, especially above 5 kHz. Measurements were made in human and artificial ear canals (tubes coupled to an IEC711 ear simulator). In both cases, the power reflectance exhibited a high-frequency notch that decreased in frequency as the residual canal length increased...
February 2018: Journal of the Acoustical Society of America
Alexander M von Benda-Beckmann, Len Thomas, Peter L Tyack, Michael A Ainslie
Passive acoustic monitoring with widely-dispersed hydrophones has been suggested as a cost-effective method to monitor population densities of echolocating marine mammals. This requires an estimate of the area around each receiver over which vocalizations are detected-the "effective detection area" (EDA). In the absence of auxiliary measurements enabling estimation of the EDA, it can be modelled instead. Common simplifying model assumptions include approximating the spectrum of clicks by flat energy spectra, and neglecting the frequency-dependence of sound absorption within the click bandwidth (narrowband assumption), rendering the problem amenable to solution using the sonar equation...
February 2018: Journal of the Acoustical Society of America
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"