bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recognition masking of auditory lateralization and pitch judgments
Authors: Massaro Dominic W. , Cohen Michael M. , Idson Wendy L. 
Published: October 2005

Two experiments determined backward and forward recognition masking functions in a lateralization task. Observers were presented with a 20-msec pure tone that differed in intensity to the two ears. The task was to indicate whether the tone came from the right or left. A second backward-masking tone interfered with the lateralization of the first test tone if it was presented within 180–250 msec of the first tone presentation. In contrast, a forward-masking tone had to be presented within 80 msec of the test-tone presentation in order to interfere with lateralization of the test tone. The results also showed that observers tended to lateralize the test sound in the direction of the masking sound if the test and masking sounds occurred within a 100-msec period. In a third experiment, subjects were required to identify a test tone as high or low in pitch in a recognition masking task. Although pitch judgments showed as much or more backward masking than lateralization judgments, significantly less forward masking was found in the pitch judgment task. Relative to lateralization judgments, observers showed a smaller tendency to judge the pitch of the test tone in the direction of the pitch of the masking sound.
Subject Classification: [43]65.75, [43]65.54, [43]65.62, [43]65.58.
Effect of interrupting recovery on loss in cochlear microphonic sensitivity
Authors: Price G. Richard 
Published: October 2005

A previous experiment [G. R. Price, J. Acoust. Soc. Am. 56, 183–189 (1974)] produced data that documented an early recovery process (ERP) measurable in the cochlear microphonic (CM) following intense stimulation. At that time, a hypothesis was advanced that if the ERP were interrupted by successive stimuli during intense intermittent stimulation, unusually large losses would result. The present experiment tested this hypothesis by comparing loss in CM sensitivity in the ears of anesthetized cats following one of three exposure conditions: (1) intermittent stimulation timed to interrupt the ERP (1 min on, variable off time), (2) the same amount of stimulation with a maximum of recovery time (1 min on, 9 min off), (3) and continuous stimulation. All ears received 30 min of stimulation with a 5.0-kHz tone at 30 dB above that intensity necessary to produce a maximum in CM output. Interrupting the ERP when 5 dB from completion resulted in 1.2 dB/min of loss, while allowing it to run to completion produced losses of only 0.6 dB/min. Continuous stimulation resulted in 0.9 dB/min of loss. The data supported the hypothesis and demonstrated the importance of the ERP. The implications of these findings for the problem of hearing loss to intermittent stimulation are discussed.
Subject Classification: [43]65.66, [43]65.40.
Absolute measurement of acoustic particle velocity
Authors: Taylor K. J. 
Published: October 2005

A method for the absolute measurement of acoustic particle velocity is described. The technique uses the Doppler shift in frequency of laser light scattered from small particles suspended in the medium and vibrating with sensibly the same amplitude as the surrounding molecules. The measurement is made over a small volume at the intersection of two focused laser beams and since no transducer is required the sound field is not disturbed. Some typical data are presented illustrating its use over the range of particle velocities 0.5–50 mm sec−1 rms and it is shown that the results should be reliable at frequencies up to 50 kHz in air and higher frequencies in more dense media.
Subject Classification: [43]85.22; [43]35.65.
Covariance between Fourier coefficients representing the time waveforms observed from an array of sensors
Authors: Hodgkiss W. S. , Nolte L. W. 
Published: October 2005

Typically, the assumption of a long observation interval is made to achieve uncorrelatedness between Fourier coefficients at different frequency indicies. An explicit relationship between observation interval length and covariance between the Fourier coefficients is obtained to provide insight as to how long the observation interval should be to approximate this desirable condition.
Subject Classification: [43]60.20.
Compound action potential (AP) tuning curves
Authors: Dallos Peter , Cheatham Mary Ann 
Published: October 2005

With a tone-on-tone masking procedure the compound action potential (AP), elicited by brief tone bursts of set frequency and intensity, was decreased by a constant fraction. The frequency–intensity pairs formed by the masker that yield this decrease generate the AP tuning curve. It is demonstrated that such tuning curves are very similar to both psychophysical tuning curves and single VIIIth-nerve-fiber tuning curves. Changes in the properties of these curves are described as functions of stimulus frequency and level, mode of masking (simultaneous and forward), and parameters of the masker.
Subject Classification: [43]65.40, [43]65.42, [43]65.58.
Sound attenuation as a function of depth in the sea floor
Authors: Hamilton Edwin L. 
Published: October 2005

Recently published data on the attenuation of compressional (sound) waves in marine sediments and sedimentary rocks as a function of frequency and sediment porosity have been added to previously published figures. The revised figure illustrating attenuation as a function of frequency (5 Hz–1 MHz), and attendant discussion, continue to support the conclusion that attenuation is approximately related to the first power of frequency in sands, muds, and sedimentary rocks. The revised figure illustrating sediment porosity versus attenuation affirms that sediment porosity is an important index property which can be used to predict sound attenuation in surficial sediments. Data were collected and illustrated on sound attenuation as a function of depth in the sea floor. It is concluded that attenuation decreases with about the −1/6 power of depth in sands. As a silt–clay sediment (mud), or turbidite, is placed under increasing overburden pressure, there may be a progressive increase in attenuation due to reduction in sediment porosity, and a progressive decrease in attenuation due to increasing pressure on the sediment mineral frame. At about 200-m depth a null point may be reached. Thereafter, pressure is the dominant effect, and attenuation decreases smoothly with depth and overburden pressure. The figure can be used to aid prediction of sound attenuation in sediment and rock layers in the sea floor.
Subject Classification: [43]30.20.
Lateralization at high frequencies based on interaural time differences
Authors: McFadden Dennis , Pasanen Edward G. 
Published: October 2005

Sensitivity to interaural time differences at high frequencies is demonstrated in a number of experiments. Two types of waveforms are used—bands of noise and two-tone complexes. Variables studied are rate and depth of fluctuation of the envelope, overall intensity, and additivity of interaural time information across frequency regions. In many conditions of listening, sensitivity to interaural time differences at high frequencies compares favorably with sensitivity at low frequencies—good performace requires only tens of microseconds of interaural time delay.
Subject Classification: [43]65.62, [43]65.68.
Asymptotic theory of scattering by a rough surface progressing over an inhomogeneous ocean
Authors: Labianca F. M. , Harper E. Y. 
Published: October 2005

A general asymptotic theory of scattering by a moving rough surface is presented. The theory is valid for a slowly varying refractive index, and for ocean-surface wave heights that are small compared with the acoustic wavelength and the ocean-surface correlation length. In contrast with the Kirchhoff or physical optics approximation, this theory is valid when the acoustic wavelength and ocean-surface correlation length are of the same order. The ocean surface is described as a sum of gravity waves of varying frequency progressing in different directions. It is demonstrated that, to a given order of approximation in the asymptotic theory, the average energy associated with signal sideband rays is precisely accounted for by a reduction of intensity of the reflected carrier. Wave number diagrams are introduced which are extremely useful for depicting the directions of the incident and scatteres rays at the surface, demonstrating the effect of varying surface-wave and acoustic frequency, and demonstrating the frequency cutoff of the sideband power spectrum. The phenomenon of Bragg resonance at glancing incidence of the carrier is also easily depicted. The theory can accomodate the effects of ray focusing, both in the carrier and sidebands, through the use of uniformly valid asymptotic expansions which account for the presence of caustics.
Subject Classification: [43]30.40, [43]30.20, [43]30.25, [43]30.30.
Reflections from focused liquid-filled spherical reflectors
Authors: Marks Barry M. , Mikeska E. Eugene 
Published: October 2005

Experimental measurements are presented for the target strength and directivity patterns of the reflections from stainless steel spherical shells filled with a mixture of carbon tetrachloride and freon (F113) in the frequency range 30–130 kHz. Five spheres were tested having nominal outside diameters of 6, 7, 10, 12, and 18 in. with varying wall thicknesses. Target strength measurements were made separately on echo components arising from reflections from the front and rear surfaces of the sphere; the focused rear-surface reflections showed target strengths up to 21 dB higher than those corresponding to the front surface, controlled by the sphere wall material and thickness, and by the index of refraction of the fluid.
Subject Classification: [43]30.30.
Simplified model of the spectral characteristics of high-frequency surface scatter
Authors: Swarts R. L. , Eggen C. J. 
Published: October 2005

Classical wave theoretical treatments can be used to predict the general characteristics of the acoustic field scattered from a roughened time-varying sea surface. Various approximations can then be invoked to handle the so-called slightly rough and very rough surface cases. In this paper an expression for the spectrum of the scattered sound is derived for the very rough case in terms of specific surface-wave parameters. This expression is then evaluated for several surface spectra, including the fully aroused Neuman–Pierson and Pierson–Moskowitz surface wave spectra. Finally, these results for special cases of the Neuman–Pierson spectra are compared with those obtained by numerically integrating the general form for the same spectra, a technique that does not involve the very rough case approximation.
Subject Classification: [43]30.40; [43]20.15.
Acoustic phase and amplitude of a signal transmitted through a uniform flow in the deep ocean
Authors: Widtfeldt J. A. , Jacobson M. J. 
Published: October 2005

Results of a previous hydrodynamical study of a uniform, deep-ocean flow are used to develop simple approximations to the sound-speed and current distributions in the flow. The behavior of sound speed with depth, surface current, and source and receiver locations is examined. The effects of the flow on ray geometry, travel time, and spreading loss are investigated for a surfaced cw sound source and bottomed receiver. Total-field amplitude and phase are determined and are found to be highly sensitive to surface-current variations and to source and receiver locations. A simple method is presented for accurately estimating amplitude and phase. Then, an approximate phase formula is developed that is proportional to surface current, linear in source location, and sinusoidal in the orientation angle of the source–receiver range.
Subject Classification: [43]30.20; [43]28.60.
Reflection of waves from a point source by an impedance boundary
Authors: Thomasson Sven-Ingvar 
Published: October 2005

The problem of finding a solution of the scalar wavefield produced by a point source in the presence of an infinite ’’impedance’’ boundary is treated. The analysis is made with a method used by Ingard, which has been corrected. It is shown that it is possible to rewrite the exact solution in terms of a single integral along a steepest-descent contour and a Hankel function. Asymptotical expansions of the solution is in consistency with expansions by Wenzel, who found that in a special case expansions of his and Ingard’s solution differ by a ’’surface wave’’ term. The asymptotical expansions are given as examples. The main result, the single integral and the Hankel function, could easily be integrated numerically.
Subject Classification: [43]28.40; [43]20.15, [43]20.30, [43]20.55.
Forced longitudinal vibration of an elastic circular rod on an elastic half-space
Authors: Saito H. , Chonan S. 
Published: October 2005

A solution is given for the problem of the forced longitudinal vibration of an elastic circular rod, one end of which is attached to the surface of an elastic half-space and to another end of which a periodic disturbing force is applied. Resonance curves for the motions of rods are derived using specific boundary conditions. Attention is directed to the effective damping of the motion of the rod due to dissipation of waves to infinity.
Subject Classification: [43]40.20; [43]20.22.
Analysis of nonlinear resonance in thickness-shear and trapped-energy resonators
Authors: Tiersten H. F. 
Published: October 2005

Electroelastic equations containing terms up to cubic in the small mechanical displacement field, but no higher than linear in the electric variables, are applied in the analysis of nonlinear resonance in rotated Y-cut quartz oscillators. Both pure thickness-shear vibrators and essentially thickness-shear trapped-energy resonators are treated. This is a natural continuation of earlier work on intermodulation in the same resonators. Since in each equation each nonlinear term is negligible compared to an associated linear term, the solutions are obtained by employing an asymptotic iterative procedure and expanding in the eigensolutions of the associated linear problem and, in the vicinity of a resonance, retaining only that nonlinear term correcting the dominant eigensolution. Lumped parameter representations of the solutions, which are valid in the vicinity of a resonance and relate the amplitude of the dominant mode nonlinearly to the voltage across the crystal, are presented for both the pure thickness-shear and trapped energy thickness-shear problems. In each instance the expression for the current through the crystal is determined, the influence of the external circuitry is included in the analysis and, ultimately, an expression cubic in the mode amplitude and linear in the driving voltage is obtained. The analyses hold for the fundamental and odd overtone thickness-shear modes. Nonlinear resonance curves are presented for AT-cut quartz using the nonlinear coefficient γ determined in earlier work on intermodulation.
Subject Classification: [43]40.24, [43]40.30; [43]85.52.
Ear dominance and intensity independence in the perception of dichotic chords
Authors: Efron Robert , Yund E. William 
Published: October 2005

The perceived pitch mixture of two tones of a dichotically presented chord was studied as a function of the difference between the intensities of the right and left ear tones (ΔI). Previous experiments have shown that, within a wide range of ΔI, the pitch mixture is independent of ΔI. This intensity independence of the pitch mixture of dichotic chords is not seen with monaural chords. Within the range of ΔI over which intensity independence is seen, the pitch mixture of the dichotic chord is determined by another property of the central pitch processor—the ear dominance function. In previous experiments the intensity independent function could only be detected in those subjects with a weak ear dominance function. In the present experiments subjects adjusted the relative intensities of the two tones of a binaural chord to match the pitch mixture of a dichotic chord. Using this method, the intensity independent function was measured directly in all subjects. In addition, the present method provides a direct measure of the magnitude of the suject’s ear dominance function and clarifies the relationship between the effects of the two functions.
Subject Classification: [43]65.75, [43]65.54, [43]65.62.
Temporal summation and decay in hearing
Authors: Irwin R. J. , Kemp S. 
Published: October 2005

Two theories of temporal summation in hearing were compared. In both theories the ear performs a running average on the incoming sound in accordance with the convolution integral. In one of the theories, called the ’’rectangular’’ theory, sound is transformed by a power function and weighted by a brief rectangular function; in the other theory, called the ’’exponential’’ theory, sound is transformed so that an initial large effect decays to a steady level and it is weighted by a decaying exponential function. The rectangular theory was shown to predict that brief tone bursts and brief gaps in a tone are equally detectable if the duration of the burst and gap are equal, but the exponential theory was shown to predict that brief tone bursts are more readily detectable than brief gaps of equal duration. Experimental findings support the exponential theory: The percentage of correct responses in a two-alternative forced-choice task was greater for tone bursts than for tone gaps of equal duration. This result was obtained for tones and gaps from 25 to 200 msec in duration and for two different levels of a 1000-Hz tone. In addition, the exponential theory, with a time constant of 5 sec−1 for the weighting function, was compatible with the relation between the percentage of correct responses and the theoretical quantity determining detectability.
Subject Classification: [43]65.68, [43]65.50, [43]65.75.
Higher harmonics of finite amplitude ultrasonic waves in solids
Authors: Thompson R. Bruce , Buck O. , Thompson D. O. 
Published: October 2005

Absolute measurements of the amplitude of the first four harmonicof 30-MHz finite amplitude ultrasonic waves are reported for fused silica samples of various lengths and for aluminum single crystals with different amounts of cold work. The harmonically distorted motion of the end of the sample is detected by a capacity microphone and the individual harmonics are then selected and amplified by a heterodyne receiver with flat frequency response from 30 to 250 MHz. The fused silica data are found to be in excellent agreement with a model of Fubini, originally developed for gases, which for solids depends on the second- and third-order elastic constants but none of the higher constants. A discussion is presented of the reasons for the insensitivity of the measurements to the values of the fourth- and higher-order elastic constants. Agreement with the model of Fubinin is not observed in single crystal aluminum. The quantitative differences are not fully consistent with existing models for dislocation contributions to harmonic generation.
Subject Classification: [43]25.15, [43]25.20; [43]35.26; [43]25.25.
Nonspherical acoustic lens study
Authors: Corbett Kevin T. , Middleton F. H. , Sternberg R. L. 
Published: October 2005

A successful short focal length radar lens design technique was adapted to the problem of nonspherical thin underwater acoustic lens development and construction. The motivation was furnished by the many sonar requirements for small size lenses capable of operation in a scanning mode. The paper includes a discussion of the computer-aided lens design, the fabrication of casting molds, the vacuum casting process, and the pattern and gain measurements on the final rubber lenses. The design was accomplished using a lens size and frequency that would be compatible with the test tank available for the work. the lenses constructed were about 7 in. in diameter, vacuum cast from 3120 RTV rubber, and were tested using an acoustic frequency of 185 KHz. The useful scanning range of the lens in these tests turned out to be ±20° from the axis. The gain of the lens was 20 dB, the main lobe beam width about 4°, and ths side lobes were from 12 to 19 dB below the main lobe. Total absorption and reflection losses were less than 1 dB. The F number of the lens was about 1.3.
Subject Classification: [43]30.80, [43]30.82, [43]30.25.
Interpretation of multipath scintillations Eleuthera to Bermuda in terms of internal waves and tides
Authors: Dyson Freeman , Munk Walter , Zetler Bernard 
Published: October 2005

Rate-of-phase and intensity spectra due to time-varying multipath interference depend essentially on a single parameter ν2 which can be interpreted as the mean-square rate-of-phase for any typical single path. MIMI 406-Hz phase and intensities are consistent with ν−1=270 and 357 sec for Eleuthera to Bermuda and Eleuthera to midstation transmissions, respectively, compared to 192 and 286 sec from a ray-geometric calculation using an internal wave model based on oceanographic observations. Internal tides play a significant but not dominant role.
Subject Classification: [43]30.20, [43]30.35.
Long-range acoustic propagation through the Gulf Stream
Authors: Levenson Coleman , Doblar Randy A. 
Published: October 2005

Acoustic charges were detonated on a line normal to the Gulf Stream and recorded near Bermuda. Received signals were analyzed in one-third-octave bands from 40 to 200 Hz and analyzed for rms value over an 8-sec period. Results indicate areas of low transmission associated with the North and South Walls of the stream that ranged between 4–10 dB. Highest levels were received from charges detonated north of the stream. These results can possibly be explained by varying sonic-layer depths and a deepening sound channel axis between Slope Water and deep warm layers of Sargasso Sea water. Other factors possibly related to received amplitude fluctuation may be internal waves and ’’patches’’ of water different from surrounding areas. Further experiments using cw sounds are being planned to delineate seasonal and angular factors.
Subject Classification: [43]30.20, [43]30.25.
Acoustic radiation from submerged plates. II. Radiated power and damping
Authors: Stuart Alan D. 
Published: October 2005

Leaky wave poles are defined as those singularities of the acoustic admittance of a fluid-loaded infinite plate that are located on the bottom Riemann sheet of the complex wave number plane and can appear near the saddle point of the complex path of steepest descent. These poles represent only the real, propagating modes in an unloaded plate. It is shown that for a point or line-excited fluid-loaded classical and Timoshenko–Mindlin plate, the value of leaky wave poles and their location relative to the saddle point are sufficient parameters to explicitly describe the radiated power, the angle, beamwidth, amplitude, and existence of the radiation lobes, and the effect of structural damping on the radiation field.
Subject Classification: [43]30.50; [43]40.24.
Identification of random auditory waveforms. II. Interaural relationships
Authors: Pollack Irwin 
Published: October 2005

Can listeners successfully identify specific waveforms, randomly selected from extremely large pools of possible signals? Can listeners also identify specific sequences of interaural relationships, randomly selected from extremely large pools of possible sequences of interaural relationships? The answer to the first question is  yes ; the answer to the second is ’’probably no.’’
Subject Classification: [43]65.62, [43]65.75, [43]65.52.