bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inferred response polarities of cochlear hair cells
Authors: Sokolich W. G. , Hamernik R. P. , Zwislocki J. J. , Schmiedt R. A. 
Published: October 2005

Single-fiber responses were recorded from the auditory nerves of kanamycin-treated gerbils whose cochleas were subsequently processed for histological examination. On the basis of their abnormal responses to inferred trapezoidal displacements of the basilar membrane, the contacted fibers were classified according to that direction of basilar-membrane deflection that was associated with their excitation. A frequency–distance map was constructed for the gerbil’s cochlea with the help of cochlear-microphonic recordings and was used to infer the location of the hair cells innervated by the contacted fibers. Our correlations indicate that fibers innervating cochlear regions substantially depleted of outer hair cells were abnormal and were scala-vestibuli excitatory. Furthermore, fibers innervating cochlear regions containing full or nearly full complements of both inner and outer hair cells were either abnormal and scala-tympani excitatory, or were normal. These response polarities are consistent with the previously proposed polarity-opposition model of interaction between inner and outer hair cells in the cochlea.
Subject Classification: [43]65.28, [43]65.35, [43]65.40, [43]65.42, [43]65.59.
Measurements of hydrodynamic noise from submerged hydrofoils
Authors: Barker Steven J. 
Published: October 2005

This paper presents the results of an experimental study of hydrodynamic noise conducted in the High-Speed Water Tunnel of the California Institute of Technology. The objective of the test program was to measure some of the basic characteristics of noise radiated from submerged hydrofoils, both fully wetted and cavitating. Measurements of fully wetted hydrodynamic noise are difficult to make due to the low intensities, but the very low background noise level of the Caltech tunnel makes it possible to measure this noise under some conditions. An increase in the angle of attack of a hydrofoil was found to produce a slight increase in noise spectrum level at high frequencies. An increase in surface roughness produced a more significant increase over a wider frequency range. Noise was measured for three distinct types of hydrofoil cavitation: blade surface cavitation, wake cavitation, and trailing vortex cavitation. Foil vibration was found to be important in blade surface cavitation, but not in the other forms. Both blade surface and wake cavitation have spectral peaks at a Strouhal number based on a cavity length of 0.5. Trailing vortex cavitation is found to be a relatively weak source of noise, owing to the fact that in the water tunnel this type of cavitation is gaseous in nature.
Subject Classification: [43]30.70, [43]30.85, [43]30.50.
Sound radiation from a semi-infinite circular pipe having an arbitrary profile of orifice
Authors: Ando Y. , Koizumi T. 
Published: October 2005

A general solution for the sound radiated from a circular pipe having an arbitrary inside profile of orifice is obtained by the use of Laplace transforms and the Wiener–Hopf technique. The pipe may include vibrating surfaces. Results are calculated for the velocity potential at a large distance from the orifice and for the reflection coefficient for the dominant-mode component of the velocity potential in the pipe. The solution is applicable, for example, to the design of an acoustic transducer, and for noise control from the orifice. Some numerical results for the velocity potential of a model loudspeaker and for the excess attenuation of a muffler near the open end of a pipe are presented graphically.
Subject Classification:[43]20.55, [43]20.15.
Radiation of difference-frequency sound generated by nonlinear interaction in a silicone rubber cylinder
Authors: Ryder J. D. , Rogers Peter H. , Jarzynski J. 
Published: October 2005

In this paper we describe an experimental and theoretical investigation of the parametric signal generated in one medium, a silicone rubber cylinder, and radiated into a second medium, water. The primary waves (∠1.4 MHz) are confined to a narrow region around the axis of the cylinder and, because of the relatively high absorption at these frequencies, are largely attenuated before reaching the end of the cylinder. The silicone rubber cylinder serves two purposes. First, the low sound speed (∠1000 m/sec) and high parameter of nonlinearity (1+B/2A?5) of the silicone rubber makes the virtual sources more than seven times as strong as they would be in water. Second, because the sound speed in silicone rubber is less than that of the surrounding water, the silicone rubber cylinder acts as a slow waveguide antenna for the difference-frequency waves. The system is analyzed by numerically solving the system of equations obtained by coupling the surface Helmholtz integral equation for the interior of the silicone cylinder (which includes the virtual sourcesI with the integral equation for the region exterior to the cylinder. Experimental results obtained for difference frequencies between 10 and 20 kHz compare favorably with theory.
Subject Classification: [43]25.35, [43]25.15; [43]30.75.
Acoustic radiation from submerged plates. I. Influence of leaky wave poles
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 wavenumber plane and can appear near the saddle point of the complex path of steepest descent. These poles are shown to represent only the real, propagating modes in an unloaded plate. It is shown that for a point or line excited plate the value of leaky wave poles and their location relative to the saddle point are sufficient parameters to explicitly describe the acoustic radiation from submerged plates. This paper analyzes the leaky wave poles of both the Timoshenko–Mindlin plate equation and the classical plate equation.
Subject Classification: [43]30.50; [43]40.24.
Identification of vowels excerpted from neutral and nasal contexts
Authors: Bond Z. S. 
Published: October 2005

In a number of previous studies, subjects have been shown to have some difficulty in identifying vowels presented in isolation, even when the vowels have been produced with considerable precision. However, equivalent precision of utterance can not be assumed in more ordinary speech situations. In the present study, the effect of two consonantal contexts on the identifiability of vowels was investigated. Six speakers produced ten monophthongal English vowels in two different phonetic contexts: neutral (h——d) and nasal. The vowels were excerpted from context and presented for identification. Subjects found the phonetic context to affect vowel identifiability significantly.
Subject Classification: [43]70.30, [43]70.40, [43]70.70.
The photophone–an optical telephone receiver
Authors: Kleinman D. A. , Nelson D. F. 
Published: October 2005

A theoretical discussion is given of optical telephone receivers employing the optoacoustic effect, which are here called photophones, for use in an optical-fiber telephone subscriber loop. The basic receiver consists of an absorption cell, a response-equalizing device such as a gas column or diaphragm, a tapered acoustic tube acting as a transformer, and an earpiece similar to a conventional telephone earpiece including a response-equalizing device. These photophones are designed to give a flat (3-dB) response to intensity modulated light over the telephone voice band 300–3300 Hz. The optoacoustic effect is treated on the basis of a pseudogas model for solid absorbers in the form of a fine mesh disbusrsed in a gas. We find that the sensitivity (the optical power modulation required to produce a sound pressure level SPL = 81 dB in a closed volume of 6 cm3, representing the earpiece pressed against the ear) is 2.8 and 0.9 mW for the air-filled and xenon-filled photophones, respectively.
Subject Classification: [43]85.76, [43]85.40, [43]85.60; [43]35.65.
Effect of flow on the acoustic reflection coefficient at duct inlet
Authors: Bohn M. S. , Zukoski E. E. 
Published: October 2005

The effect of duch Mach number upon the acoustic reflection coefficient at the inlet of a duct with mean flow is investiagted. An analysis, which models the duct inlet as a very short, one-dimensional nozzle over which the mean flow is accelerated from rest, gives good agreement with some recent experimental results. Discrepancies between the analysis and he experimental results are discussed in terms of radiation losses at the inlet and real fluid-flow effects within the duct.
Subject Classification: [43]28.60; [43]20.30.
Reply to ’’Comments on ’Influence of rotary inertia and shear deformation on acoustic transmission through a plate’ ’’ [J. Acoust. Soc. Am. 59, 1500–1501 (1976)]
Authors: Stepanishen P. R. 
Published: October 2005

The expression and numerical results in the original letter were based on the use of Timoshenko–Mindlin plate theory and thus have an inherent frequency–plate-thickness limitation when compared to results based on the use of elasticity theory. This limitation, which is noted by Young, was already noted, however, in the concluding section of the original letter. In addition it is noted that the second acoustic coincidence lobe was not attributed in the original letter to a dilatational mode, but was attributed to a flexural wave whose phase velocity at high frequencies approaches the velocity of a dilatational wave in an infinite elastic medium.
Subject Classification: [43]30.50; [43]20.60; [43]40.24; [43]20.30.
Correlation of acoustic wavefront and signal time-base instabilities in the ocean
Authors: Williams Ross E. , Wei Chao H. 
Published: October 2005

Wavefront fluctuations, rotations, and distortions, measured for a particular arrival in the multipath set for long-range propagation, were cross correlated with acoustic-signal time-base distortions for the same arrival. Although the wavefront perturbations contain higher frequency components than for the signal time-base fluctuations, significant cross correlation amplitudes were found for time and rotation, time and distortion, and distortion and rotation cross correlations. The results demonstrate that common causes, such as tides, overtides, and internal waves, underlie both the temporal and spatial perturbations of the acoustic signal. Although these perturbations were significantly correlated in a high percentage of the tests, the degree of correlation between them was not stable over periods of days or weeks.
Subject Classification:[43]30.20, [43]60.20.
Model for predicting the reflection of ultrasonic pulses from a body of known shape
Authors: Johnson D. M. 
Published: October 2005

An approximate model for determining the response functions of reflectors of known shape has been used to provide theoretical support for experimental investigations of flaw characterization. The reflection of broad-band ultrasonic pulses from an object can result in modifications to both the frequency spectrum and phase information in the pulses. These changes are largely controlled by the parameters of the reflector, and relating these factors has been the subject of many experimental investigations. Within the fundamental approximations, the model can readily be applied to any reflector of known shape and provides a simple interpretation of what is physically occurring. It has the advantage that additional experimental factors can be included to determine their effect on the results.
Subject Classification: [43]35.26; [43]20.30; [43]35.80.
Theorem on the scattering and the absorption cross section for scattering of plane, time-harmonic, elastic waves
Authors: Tan T. H. 
Published: October 2005

In a homogeneous, isotropic, perfectly elastic medium a scattering obstacle of finite extent is present. When a plane, time-harmonic, elastic compressional (P) or shear (S) wave is incident on it, the extinction cross section (i.e., the sum of the scattering and the absorption cross section) of the obstacle is directly related to the far-zone amplitude of the particle displacement of the scattered wave, observed exactly behind the obstacle. This relationship is discussed. In spite of the fact that in elastodynamic scattering the scattered P wave as well as the scattered s wave contribute to the time-averaged scattered power, the extinction cross section appears to depend only on the value of that farfield scattered-wave amplitude which is of the same type (P or S) as the incident wave.
Subject Classification: [43]20.15, [43]20.30.
Use of a spherical concave reflector for jet-noise-source distribution diagnosis
Authors: Chu W. T. , Kaplan R. E. 
Published: October 2005

An account on the development of a directional microphone system for jet-noise-source strength distribution measurements is given. The system selected is based on the imaging principle of a spherical concave reflector. As expected, the system is diffraction limited; a loss of resolution results. A special technique is discussed to recover the axial-source strength distribution from the diffracted data. Sample experiments are presented to show the successful application of such a system for jet noise measurements.
Subject Classification: [43]28.65; [43]50.55; [43]85.62.
Spatial interfrequency correlation effects in a surface-scatter channel
Authors: McDonald J. F. , Tuteur F. B. , Zornig J. G. 
Published: October 2005

The effect of spatial separation on the cross correlation between the system response functions for a two-receiver surface-scatter channel is investigated. The system response at the two receivers is determined for all possible pairs of frequencies. The analysis assumes relatively close separation of receivers and uses the Fresnel-corrected model for surface scatter in the specular direction. The surface is assumed to be Gaussian, with typical size of boundary deformations small compared to typical Fresnel zones.The analysis shows that the correlation is approximately maximum for zero-frequency separation and drops off at a rate determined by the reverberation time. For small reverberation times and small grazing angles correlation may extend over fairly large values of frequency difference. The effect of spatial separation is generally a reduction in correlation and a more rapid decrease of correlation with frequency, but this can be compensated to some extent by time shift between the two system responses. Experimental evidence is included to support the theoretical predictions presented.
Subject Classification: [43]30.20; [43]20.15; [43]60.20.
Evaluation of transducer window materials
Authors: Mikeska E. Eugene , Behrens John A. 
Published: October 2005

Acoustic measurements of insertion loss and echo reduction at normal incidence were made for thin plates of eight materials for evaluation of their use in underwater sound transducers in the frequency range 50–500 kHz. Materials tested included Lucite; silicone rubber RTV– 560; the commercial polyurethane products PRC–1527, CPC–19, Scotchcast 8, and Scotchcast 221; and two of these materials with talc added during curing to vary the properties. Values of longitudinal sound velocity, attenuation constant, and characteristic impedance are derived from comparison of theoretical and measured characteristics.
Subject Classification: [43]30.30; [43]40.55; [43]55.75; [43]85.40.
Whispering Gallery wave modes on elastic cylinders
Authors: Dickey J. W. , Frisk G. V. , Überall H. 
Published: October 2005

We present an analytic and numerical study of Whispering Gallery-type surface- wave modes on solid elastic cylinders imbedded in a fluid. The complex wave numbers of these waves are obtained for the case of high frequencies (ka≳15), including both their attenuation and dispersion curves for the phase velocities. It is shown that there are two different groups of Whispering Gallery modes whose wave numbers in the limit of infinite frequency or infinite cylinder radius approach the corresponding wave numbers of compressional and shear bulk waves in the cylinder material.
Subject Classification: [43]40.20; [43]30.50; [43]40.55; [43]20.15; [43]35.54.
Transmissibility across clamped circular plates with central loading masses and various rib configurations
Authors: Ochs J. B. , Snowdon J. C. , Kerlin R. L. 
Published: October 2005

The tranmissibility between the midpoint and the boundary of thin, symmetrically vibrating, circular, aluminum plates of identical dimensions has been determined experimentally in the frequency range 16–2000 Hz. The plates were clamped at their boundaries and loaded symmetrically by concentrated masses or by distributed masses (ribs) of various configurations. The loading masses were always equal to the plate mass, so that their effectiveness in reducing transmissibility could be evaluated as a function of their geometry. Consideration was given to continuous and segmented effectiveness in reducing transmissibility could be evaluated as a function ribs. The transmissibilities across plates loaded centrally by cylindircal masses of small and intentionally large contact areas, and by continuous and segmented circular ribs of small and large diameters, agreed closely with prediction, encouraging belief in the validity of the experimental results obtained for the remaining plates loaded by noncircular ribs, which had theoretically intractable geometries. The transmissibilities across an unloaded plate and a plate plus damping tile also agreed satisfactorily with prediction, even though the transmissibility across the damped plate was calculated from an expression developed for a homogeneous plate with internal damping. The greatest overall reductions in transmissibility were provided by the central loading masses, particularly by the mass having small contact area. By comparison, the reductions provided by the various rib configurations were disappointing; only the performance of the triangular rib and of the small circular rib approached that of the central masses, suggesting use of these ribs when access to the plate center is necessary.
Subject Classification: [43]40.24, [43]40.20.
Huygens’ principle, radiation conditions, and integral formulas for the scattering of elastic waves
Authors: Pao Yih-Hsing , Varatharajulu Vasundara 
Published: October 2005

Helmholtz- and Kirchhoff-type integral formulas are presented for elastic waves in isotropic and anisotropic solids. The displacement vector field at points interior and exterior to a region bounded by a closed surface is expressed in terms of a volume integral of the body sources and a surface integral of the sources on the closed surface, namely, the traction and the displacement. The kernels of these integrals are the well-known Green’s displacement dyadic and a third rank Green’s stress tensor. The latter is related to the former by generalized Hooke’s law. From these formulas radiation conditions for both steady-state and transient elastic waves are established in terms of the traction, displacement, and particle velocity. In the Kirchhoff-type formula, the retardation in time for the surface and volume sources is made with respect to the travel times for dilatational and shear waves, respectively. This clearly illustrates Huygens’ principle for the two wave fronts of the elastic wave field.
Subject Classification: [43]40.20, [43]40.55; [43]20.15.
Fourth-order dispersion of free longitudinal waves in a long orthotropic bar of rectangular cross section
Authors: Zuckerwar Allan J. 
Published: October 2005

A perturbation technique described previously is applied to find the dispersion of free longitudinal waves in a long orthotropic bar of rectangular cross section as far as the fourth order of approximation. First the second-order equations of motion and equations of compatibility are solved to find the second-order stress distributions; then these are used to derive the exact second- and fourth-order dispersion terms. The second- order stresses are related to a homogeneous and a nonhomogeneous potential function. The homogeneous potential function may be described by one of three analytical expressions, depending upon whether the following combination of elastic compliances is less than, greater than, or equal to unity:
A = (s11s33−s13 2) (s22s33−s23 2) / [(s12s33−s13s23) +(1/2) s33s66]2.
Measurements of the first two frequencies of two potassium chloride specimens, having different major orientations, are compared with theoretical predictions; the percent differences are 0.06%, 0.12%, 0.07%, and &lt;0.01%, all of which lie well within the bounds permitted by the uncertainties in the governing parameters.
Subject Classification: [43]40.22, [43]40.20; [43]20.15.
Effect of air flow, panel curvature, and internal pressurization on field-incidence transmission loss
Authors: Koval Leslie R. 
Published: October 2005

In the context of sound transmission through aircraft fuselage panels, equations for the field-incidence transmission loss (TL) of a single-walled panel are derived that include the effects of external air flow, panel curvature, and internal fuselage pressurization. These effects are incorporated into the classical equations for the TL of single panels, and the resulting double integral for field-incidence TL is numerically evaluated for a specific set of parameters. Flow is shown to provide a modest increase in TL that is uniform with frequency up to the critical frequency. The increase is about 2 dB at Mach number M = 0.5, and about 3.5 dB at M = l. Above the critical frequency where TL is damping controlled, the increase can be slightly larger at certain frequencies. Curvature is found to stiffen the panel, thereby increasing the TL at low frequencies, but also to introduce a dip (analogous to the coincidence dip at the critical frequency) at the ’’ring frequency’’ of a full cylinder having the same radius as the panel. This effect, up to now qualitatively understood, can now be quantitatively estimated. Pressurization appears to produce a slight decrease in TL throughout the frequency range, and also slightly shifts the dips at the critical frequency and at the ring frequency.
Subject Classification: [43]50.50, [43]50.45; [43]55.80, [43]55.75.
Double eigenvalues of soft circular ducts containing uniform flow and sheared flow
Authors: Tseo Gus G. 
Published: October 2005

Numerical methods to compute double eigenvalues for circular ducts containing uniform and sheared flow are presented. A technique to verify both the maximum exponential decay and the double eigenvalue, impedance, and attenuation in ducts of different sizes are presented and discussed. For well cut-on modes in a uniform-flow duct, the impedance velocity by a simple relationship suggested in a previous study. However, in a sheared-flow duct, optimum impedances are found to have much smaller values than in the uniform-flow case.
Subject Classification: [43]50.40; [43]20.45, [43]20.40.