bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlates of combination tones observed in the response of neurons in the anteroventral cochlear nucleus of the cat
Authors: Smoorenburg Guido F. , Gibson Mary Morton , Kitzes Leonard M. , Rose Jerzy E. , Hind Joseph E. 
Published: October 2005

Neurons in the anteroventral cochlear nucleus of the cat respond to combination tones of the forms f2−f1 and f1−n (f2−f1), where n is a small positive integer 1, 2, 3,.... The most easily observed combination tones are f2−f1 and 2f1−f2. In general, a combination tone is effective if three conditions are fulfilled: (1) the combination-tone frequency must fall within the pure-tone response area of the neuron; (2) the intensity levels of the primaries must be appropriate; and (3) the separation of the primary frequencies cannot be unduly large. For any form of combination tone, a combination-tone response area could be plotted by fixing f1 at some level and varying f2 in small steps. The actual frequency of the combination tone could be determined from the timing of the discharges for all neurons whose discharges are phase locked. The combination-tone response areas indicate that the response to a given form of combination tone is optimal when the combination frequency is at or near the best frequency of the neuron. Moreover, the combination-tone response areas are similar in width to the pure-tone response area of the neuron. These findings suggest that the neuron responds to combination tones as if such tones were actually delivered to the ear. It was further found that the combination-tone frequencies that activate the neuron may be several octaves below the frequencies of the two primaries that produce the combination tone. Combination-tone threshold and suprathreshold studies show that the combination-tone level increases with decreasing separation of the two stimulus components. Levels of the combination tones expressed in equivalent decibels of SPL increase approximately proportionately with stimulus level (L1=L2) for both f2−f1 and 2f1−f2. Furthermore, for both these combination tones, the combination-tone level as a function of L2 (L1 fixed) shows a peaked curve with the maximum occurring when L2 is about equal to L1. The types of combination tones encountered and the effects of variations in stimulus frequency are in accord with psychophysical findings. The effect of stimulus level on combination tone level is in agreement with psychophysical observations for 2f1−f2 but seems to disagree with most psychophysical data for f2−f1 at higher stimulus frequencies. The results suggest that a marked nonlinearity is involved in cochlear processing, at least in the 40- to 90-dB-SPL range.
Subject Classification: [43]65.56, [43]65.42, [43]65.40.
The cochlear compromise
Authors: Zweig G. , Lipes R. , Pierce J. R. 
Published: October 2005

It is conjectured that the design of the cochlea is influenced by two conflicting requirements: (1) the cochlea should act as a precise frequency analyzer and (2) waves propagating along the basilar membrane should be transmitted without reflections. Accurate frequency analysis is possible only if the mechanical properties of the cochlea change rapidly with distance along the basilar membrane. Reflections of waves traveling on the basilar membrane will be negligible, however, only if these same mechanical properties change slowly. A compromise between these two requirements is possible if a loss constant δ related to the sharpness of response of the basilar membrane to a pure tone is related to the number N of wavelengths of the wave on the basilar membrane [N/(δ)1/2?1]. Furthermore, if sizable changes in the displacement occur only over distances larger than the width of a hair cell, then δ must be larger than the ratio of the width w of a hair cell to the distance d along the basilar membrane over which the characteristic frequency changes by an octave [δ≳4N (2δ)1/2 w/d]. These remarks are made explicit in a transmission-line model of cochlear mechanics. A simple closed-form solution of the equations, which agrees with a numerical solution, is given. The solution is compared with Mössbauer measurements of basilar membrane motion. Agreement with experiment is good if N and δ are chosen appropriately. These values are consistent with both of the conjectured relations and indicate that δ is the same order of magnitude as its lowest possible value.
Subject Classification: [43]65.26, [43]65.35.
Poster sessions at the 89th Meeting of the Acoustical Society of America
Authors: Chial Michael R. , Hopper Robert , Whitehead Jack L. , Smith Alfred G. 
Published: October 2005

Behavioral observations of communication interaction patterns were gathered for traditional and ’’poster paper’’ presentations at the 89th Meeting of the Society (7–11 April 1975, Austin, Texas). Affective reactions of poster paper authors and audience members were also surveyed. The overall response to poster sessions was very positive, suggesting continuation of the new mode of technical communication. Poster paper authors were somewhat more positive in their responses than other participants. Although poster sessions produced much more verbal interaction, patterns of interaction did not appear to differ from those observed in traditional presentations. Several problems particular to poster sessions were identified and suggestions for improvement are offered.
Subject Classification: [43]05.50; [43]10.85.
Hearing sensitivity of the mongolian gerbil, M
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Authors: Ryan Allen 
Published: October 2005

Mongolian gerbils were trained to respond to pure tones in a shock-avoidance task. The animals proved to be readily trainable and behaviorally stable. Thresholds were obtained by a method of limits and, in the case of one animal, by generating psychrometric functions. The gerbil responds to frequencies between 0.1 and 60.0 kHz. For pure tones between 1.0 and 16.0 kHz, the threshold of hearing averages 4.6 dB SPL. Between 1.0 and 0.1 kHz, sensitivity declines at a rate of 12 dB/octave. Between 16.0 and 40.0 kHz, threshold increases at a rate of 13 dB/octave, and above 40.0 kHz at a rate of 66 dB/octave. Thresholds derived from psychometric functions were essentially identical to those obtained by the method of limits. Hearing in this species is consistent with its size and anatomical characteristics.
Subject Classification: [43]80.50; [43]65.50.
Theory of normal modes and ultrasonic spectral analysis of the scattering of waves in solids
Authors: Pao Yih-Hsing , Mow C. C. 
Published: October 2005

A theory of the spectral analysis of the scattering of elastic waves is presented and illustrated with numerical results for the scattering by a circular cylindrical fluid inclusion in a solid. When the spectral frequencies are nearly equal to the real parts of the principal frequencies of the fluid inclusion in free vibration, the power spectrum of the scattered pulses undergoes a rapid rise and fall in magnitude because of the selective transmission of an incident wave. The conspicuous peaks and valleys of the backward and forward scattering spectra can be identified with the overtone frequencies of the two lowest normal modes of the cylinder, from which the characteristics of the fluid inclusion, the ratio of the wave speed to radius, can be determined.
Subject Classification: [43]20.15, [43]20.30.
Reflection of acoustical waves at porous boundaries
Authors: Roetman E. L. , Kochhar Ram P. 
Published: October 2005

The reflection and transmission of plane harmonic waves impinging from air to the plane face of porous material occupying a semi-infinite space as well as with finite thickness is considered. The variation of these coefficients with the angle of incidence and various parameters (frequency, permeability, etc.) is illustrated for certain porous materials. The results obtained indicate that the transmission coefficient remains the same under the assumption of velocity potential (there is no velocity potential in general in the porous material) while the reflection coefficient changes significantly.
Subject Classification: [43]20.30, [43]20.35.
Propagation of beamed signals through inhomogeneous media: A diffraction theory
Authors: McCoy J. J. , Beran M. J. 
Published: October 2005

A theory, which is suitable for making estimates of the acoustic field radiating from either a completely coherent (i.e., deterministic) or a partially coherent source is derived and discussed. The theory outputs are measures of beam bending and spreading due to refraction and diffraction. For the random source problem, the theory also provides estimates of the coherence of signals received by pairs of spatially separated hydrophones. The theory is based on an approximation that may nominally be termed parabolic. The limits of validity of the various approximations are discussed and a solution algorithm, which might be classified as an extended ray-trace algorithm, is presented. A special case, in which this algorithm can be carried out analytically, is dicussed.
Subject Classification: [43]30.20; [43]60.20; [43]30.35; [43]20.30.
Long-range acoustic propagation paths: Antigua–Newfoundland
Authors: Nutile D. A. , Guthrie A. N. , Fitzgerald R. M. , Shaffer J. D. 
Published: October 2005

The propagation paths from shallow explosive sources to a SOFAR axial receiver are determined by analyzing measured shot signatures. The charges were detonated along a 2800-km track between Antigua and Newfoundland. Propagation was through several distinct water masses, each of which produced different observable effects on the shot signature. Because of the shallow depth of the source, the number of turning points below the SOFAR axis is the prime determinant of the time dispersion of the arrivals and is a convenient basis for classifying them. The range dependence of the dispersed arrivals depends on the large-scale oceanography and discloses the identity of the ray paths which produce it.
Subject Classification: [43]30.20.
Acoustic signatures from deep water implosions of spherical cavities
Authors: Orr Marshall , Schoenberg Michael 
Published: October 2005

Hollow glass spheres of various sizes have been preweakened to implode at ocean depths of approximately 3 km and sunk using chain weight. Acoustic signals generated from the implosion of these spheres have been analyzed. Pressure signatures, energy-density spectra, and total acoustic energy in the frequency band 96–5000 Hz are presented. The signatures of all the implosions have many features in common. Basically each consists of a low flat negative-pressure pulse followed by a sharp positive-pressure spike of roughly 0.2-msec duration. The efficiency of the conversion of available potential energy to radiated acoustic energy is approximately 18%. Total radiated acoustic energy for spheres of 43.2-cm diameter imploding at a 3-km depth is about 53 dB re 1 J. Preweakened glass spheres show promise as a tool in the study of the sedimentary structure of the ocean bottom due to the impulsive character of the signal that is radiated upon implosion.
Subject Classification: [43]30.50, [43]30.60, [43]30.70.
Hidden depths: Acceptable ignorance about ocean bottoms
Authors: Williams A. O. 
Published: October 2005

Normal-mode analysis of underwater sound propagation in principle requires knowledge of pertinent physical parameters at all depths in the water and the bottom material—an unattainable omniscience. We present a method for determining the maximum depth to which this knowledge is necessary in order to hold the fractional errors in mode eigenvalues to prescribed limits. Let hn represent a vertical distance below the lower turning point of the nth-mode solution. Insertion or removal of a horizontal plane reflector, at this depth, alters the mode eigenfunction and therefore the eigenvalue En. The fractional error ΔEn/En is a calculable function of hn; this error being stipulated, hn can be found. The calculation need be made only for the highest mode that contributes significantly. Conversely, if all parameters are known to depth h, the consequent errors can be found. Two examples are analyzed, with simplifying restrictions: deep isovelocity water, low frequencies, many modes, bottoms that are isovelocity (the Pekeris case) or have a positive gradient of sound speed. For fractional errors of 10−4 to 10−6, h is a few acoustic wavelengths. In each example, bottom absorption has little effect on the result.
Subject Classification: [43]30.20, [43]30.50, [43]30.25.
Convergence of an iterative solution for a class of nonlinear vibration problems
Authors: Stani?ić M. M. 
Published: October 2005

A nonlinear equation describing the motion of a nonlinear oscillator has been reduced by proper substitution to an integro-differential equation and then solved by means of an iterative technique for an arbitrary forcing function. The effect of the nonlinear terms on the convergence has been studied. It has been shown that such a solution converges sectionally in an interval Δτ. An inequality has been determined which yields a maximum Δτ regardless of the form of the forcing function if ε=0. However, for a nonzero ε the interval of convergence is highly dependent of the form of the forcing function.
Subject Classification: [43]40.30, [43]40.20.
Power spectral representation of nonstationary random processes defined over semi-infinite intervals
Authors: Mark William D. 
Published: October 2005

A new sequence of locally time-averaged power spectra is defined that describes the time evolution of the frequency content of nonstationary random processes and linear system impulse response functions. The exact input-response relations for these spectral sequences are shown to be finite discrete convolutions of the input and system spectral sequences. Expressions for the coefficients of a Laguerre function expansion of the time-varying mean square response are derived from the response spectral sequence, and the time resolution and convergence of the expansion are discussed. Simple formulas are derived for generation of the spectra from recorded sample functions using Fourier transform computational algorithms. The relationship of the spectra to the Laplace transform is also developed. Physical interpretation of the spectra is discussed in detail and related to the uncertainty principle for Fourier transforms.
Subject Classification: [43]45.40; [43]60.20; [43]20.50; [43]30.30; [43]40.35.
Acoustic reflex threshold of the chinchilla as a function of stimulus duration and frequency
Authors: Woodford C. M. , Henderson D. , Hamernik R. P. , Feldman A. S. 
Published: October 2005

Acoustic reflex thresholds and the threshold-duration function were obtained from 27 chinchilla. The reflex threshold was found to be approximately 20 dB lower than that of man with a small frequency effect evident after correction for sound pressure transformation function of the pinna and external auditory meatus. The temporal integration function reflected by acoustic reflex threshold is of much greater magnitude than that obtained psychophysically in chinchilla and man.
Subject Classification: [43]65.50, [43]65.24, [43]65.68.
Linguistic uses of segmental duration in English: Acoustic and perceptual evidence
Authors: Klatt Dennis H. 
Published: October 2005

The pattern of durations of individual phonetic segments and pauses conveys information about the linguistic content of an utterance. Acoustic measures of segmental timing have been used by many investigators to determine the variables that influence the durational structure of a sentence. The literature on segmental duration is reviewed and related to perceptual data on the discrimination of duration and to psychophysical data on the ability of listeners to make linguistic decisions on the basis of durational cues alone. We conclude that, in English, duration often serves as a primary perceptual cue in the distinctions between (1) inherently long verses short vowels, (2) voiced verses voiceless fricatives, (3) phrase-final verses non-final syllables, (4) voiced versus voiceless postvocalic consonants, as indicated by changes to the duration of the preceding vowel in phrase-final positions, (5) stressed verses unstressed or reduced vowels, and (6) the presence or absence of emphasis.
Subject Classification: [43]70.40, [43]70.70, [43]70.20.
Dimensionless parameters for use in presenting acoustical data
Authors: Romer I. Carl 
Published: October 2005

A dimensional analysis of the equations of continuity, momentum, and energy is performed which yields independent dimensionless parameters for use in presenting monochromatic acoustical data. These parameters include the heat capacity ratio γ and the Prandtl number cpμ/k of the material through which the sound is transmitted, an acoustical Reynolds number ρL2ω/μ, and the dimensionless group Lω/c. To illustrate the use of these parameters, the classical Kirchhoff–Helmholtz formulae for sound propagation through gases contained in tubes have been presented in dimensionless form.
Subject Classification: [43]20.15, [43]20.35.
Dichotic pitch fusion
Authors: van den Brink G. , Sintnicolaas K. , van Stam W. S. 
Published: October 2005

The frequency limits within which dichotic pitch fusion occurs have been measured as a function of the frequency. The relative frequency differences for the centers of the fusion frequency bands for pure tones coincide with those for binaural diplacusis at corresponding frequencies. A complex (residue) sound fuses only if the fusing conditions for all its individual spectral components are fulfilled. Dichotic fusion of repetition pitch (produced by mixing noise with the same noise, delayed) occurs only if the same noise source is used to produce the signals that are presented to the two ears. Some additional data are presented from experiments with dichotic stimulation with tones of different intensities, where a monotic pitch shift towards the loudest signal is found.
Subject Classification: [43]65.54, [43]65.62.
Modification of vocalizations of preschool deaf children by vibrotactile and visual displays
Authors: Goldstein Moise H. , Stark Rachel E. 
Published: October 2005

Three groups of four preschool children who were profoundly deaf or had severe hearing impairment were given training to produce constant–vowel (CV) syllables. One group palpated a vibrotactile vocoder-type display of the acoustic signals. One group used an analogous visual display. Children in the third (control) group were given reinforcement in the form of slide or puppet displays. In the initial sessions, all three groups of children were trained to vocalize in response to a ’’light out’’ signal. No displays were used. The children were then trained to pay attention to the displays and to model CV syllable series presented by the experimenter. In the final sessions all three groups of children were given a model CV syllable series and encouraged to respond by vocalizing when given the microphone and a ’’light out’’ signal. At the same time they had to attend to the tactile, visual, or nonspeech display. The ratio of CV syllables to all syllables, (CV+V), was calculated for each child for the initial and for the final sessions, and the difference score obtained. The paired observation t-test indicated a significant increase in the ratio for the experimental groups and no significant change for the control group. We conclude that the acoustically driven nonauditory displays were an essential factor in the observed change in CV production.
Subject Classification: [43]70.75; [43]65.82, [43]65.64, [43]65.70.
Comments on ’’Influence of rotary inertia and shear deformation on acoustic transmission through a plate’’ [J. Acoust. Soc. Am. 58, 741–745 (1975)]
Authors: Young J. W. 
Published: October 2005

The transmission loss of an acoustic plane wave through a steel plate in water has been computed using Timoshenko–Mindlin plate theory and exact elasticity theory. Good agreement between the two models is found up to a frequency–thickness product of 20 kHz in. At 40 kHz in. and above, limitations of the plate theory approach become apparent.
Subject Classification: [43]30.50; [43]20.60; [43]40.24; [43]20.30.
Auditory discrimination of the onset–offset phase of tone bursts
Authors: Rajcan Emil 
Published: October 2005

The difference limen for onest–offset phase was measured for tone bursts with an integer number of periods, rectangular envelopes, and durations between 4 and 128 msec. The difference limen was found to be smaller at 1000 Hz than at 250 and 4000 Hz, and to increase as the duration of impulses increased.
Subject Classification: [43]65.60, [43]65.75.
Additional sound absorption measurements in near-freezing sea water
Authors: Garrison G. R. , Early E. W. , Wen T. 
Published: October 2005

Sound propagation measurements at 10, 20, 30, 40, and 60 kHz were made in April 1974 under the ice pack near Pt. Barrow, Alaska. Absorption coefficients were calculated for each frequency and have been reported in detail [G. R. Garrison et al., J. Acoust. Soc. Am. 58, 608–619 (1975)]. In April 1975, an attempt was made to furnish more accurate results at the lower frequencies by measuring the absorption at 7, 13, 20, 30, and 60 kHz. The 1975 measurements gave the following results for the absorption coefficients dB/kyd at a temperature of −1.6 °C and a salinity of 32%: 0.2±0.4 at 7.1 kHz; no data at 13 kHz because of transducer failure; 3.9±0.2 at 20 kHz; 7.2±0.3 at 30 kHz; and 13.1±0.5 at 60 kHz. These values indicate a relaxation frequency, due to MgSO4, of 36±3 kHz, which is slightly above our previous results, but still much lower than that predicted by the Schulkin–Marsh equation for a temperature of −1.6 °C.
Subject Classification: [43]30.20.
Spatial and temporal fluctuations of acoustic signals propagated over long ocean paths
Authors: Williams Ross E. , Wei Chao H. 
Published: October 2005

Acoustic wavefront fluctuations and time-base distortions were measured on a long linear receiving array with a 2000 ft vertical aperture. The receiving hydrophones were buoyed slightly off the ocean bottom in a roughly uniform distribution over the aperture length. Continuous acoustic transmission up to 17.6 h of a hyperbolic FM signal with a frequency sweep from 350 to 450 Hz was used in each of seven experiments at ranges of 145, 250, 495, and 635 NM to measure signal time-base distortions. Simultaneously, wavefront fluctuations were determined from changes in arrival time across the aperture of a 10-msec 400-Hz pulse from the same projector. Wavefront fluctuations, rotations, and distortions were calculated and compared to signal time-base distortions measured on a narrow beam directed toward the incoming arrivals. Both RSR (define) and completely refracted path were insonified. In the total wavefront fluctuation, the rotation part was dominant. However, remarkably small standard deviations ranging from 5 to 15 ft over the entire aperture were found for wavefront rotations and distortions. The spectra of the measured time fluctuations and wavefront rotations and distortions reveal common causes, such as tides, overtides, and internal waves.
Subject Classification:[43]30.20.
Deconvolution processing for a nonuniform array
Authors: McDonough R. N. 
Published: October 2005

An ambient acoustic field is assumed to be observed through a delay-and-sum beamformer, in conjunction with a line array of non-uniformly-spaced sensors. The beamformer output power, as a function of steering direction, is related to the angular power density of the acoustic field through a certain integral equation, with the kernel being the known power response pattern of the array. In this note, we present the results of some computer experiments concerned with solving this integral equation by working directly in the angle domain, rather than in the wave-number spectral domain. The method is general for any array, but is of interest mainly in the case of a non-uniformly-spaced array, to which our examples correspond.
Subject Classification: [43]60.20, [43]60.30; [43]30.82.