bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theory of groove deformation in phonograph records
Authors: White James V. 
Published: October 2005

This paper describes a theory for predicting the vibrational motion of a phonograph stylus sliding in a modulated record groove. Previous theories of this interaction suffer from two main defects: (1) they are based on the assumption that the groove deformation is perfectly elastic, whereas groove impedance data have shown that this assumption is inappropriate at both high and very low tracking forces; (2) they are based on the assumption that the groove wall shape is paraboloidal in the stylus-contact region. This second assumption is inappropriate when the recorded wavelength is comparable to the width of the contact region and leads to a complete breakdown in these theories at very short wavelengths, where scanning loss is important. This paper describes a generalized formulation of the stylus–groove interaction in which the nonlinear deformation properties of the groove are specified in terms of several functions that can be determined experimentally by measuring the mechanical impedance of an unmodulated groove and by measuring scanning loss. The resulting theory is consistent with existing data on groove impedance and scanning loss. Predictions of nonlinear playback distortion based on this theory compare favorably with experimental results reported by Woodward and Werner on difference-tone distortion. More comparisons with experiment are needed to determine the range of validity of the theory.
Subject Classification: 85.66, 85.68.
Hydroacoustic transduction
Authors: Bouyoucos John V. 
Published: October 2005

Professor Hunt once asked, ’’Can you ’blow’ a whistle under water?’’ This question was perhaps the first of a series of events that has led to the emergence of a new power-conversion technology for the efficient conversion of hydraulic power to acoustic or vibratory power. This hydroacoustic power-conversion process embodies flow-switching techniques that are analogous to switching methods that are employed in electronic dc to ac power-conversion practice. The hydroacoustic technology has been developed for the generation of high-power underwater sound for communication and echo location and for such industrial uses as high-frequency rotary percussion rock drilling and pile driving. The origins of the power-conversion technology are reviewed, analytical models used for predicting equipment performance are described, and illustrations of specific applications anticpated by Hunt and the author are set forth.
Subject Classification: 10.60; 30.70; 28.65; 85.40.
The status and future of nonlinear acoustics
Authors: Westervelt Peter J. 
Published: October 2005

In addition to serving as an ideal discipline for introducing the concepts of quantum field theory and general relativity, nonlinear acoustics provides a new means for absorbing and generating sound. The many applications of this exciting subject are based in part on the fact that, in common with vector (electromagnetic and shear) and tensor (gravitational) waves, the scalar sound wave transports energy, angular momentum, linear momentum, and, incidentally, information. The methods of nonlinear acoustics can account for such disparate phenomena as the parametric array and the radar time delay in a gravitational field; the absorption of sound in superfluid helium and shock-wave attenuation in a gas; radiation pressure and sonic boom; the scattering of sound by sound; and the generation of gravitational waves. Based on the ability of nonlinear acoustics to subsume within its methodology, and hence to unify, different physical processes, as well as its demonstrated ability to contribute solutions to practical problems, it semms reasonable to expect that this subject will become a part of the curriculum in more colleges and universities than is the case at present.
Subject Classification: 10.60; 25.10.
F. V. Hunt as author
Authors: Schenck Harry A. 
Published: October 2005

Professor F. V. Hunt documented what he thought, what he invented, what he learned, and what he accomplished. During a 40-year period, he published over 50 papers and reports. He also authored numerous technical memoranda, one complete book and sections of others, and many key speeches. Many of these contributions were in his classical field of interest, acoustics. However, he made significant contributions in other fields, such as improved instrumentation and education. Through open and classified publications, Professor Hunt greatly influenced the development of U.S. Navy sonar systems. The breadth and impact of this record of accomplishment is examined. Special attention is given to describing the evolution and status of two unfinished books. One of these manuscripts was developed initially to be a major textbook on physical acoustics. The other manuscript began its life as a historical introduction to the text on physical acoustics, became at times a scholarly hobby for Professor Hunt, and grew into a mature draft for a separate book on Origins in Acoustics.
Subject Classification: 05.60; 10.60.
Measurement of acoustic intensity in reactive sound field
Authors: Schultz Theodore J. , Smith P. W. , Malme C. I. 
Published: October 2005

The usefulness of direct measurements of vector intensity for the calibration of acoustic transducers has been studied by laboratory experiments in anechoic and reverberant chambers and by analysis. Determination of total power output is feasible by intensity measurements in the nearfield and in reverberant spaces, situations where pressure measurements would be inadequate without elaborate calculation. However, the directional distribution of intensity differs from the farfield, free-space directivity both near a source and far from a source but in a reverberant space. Analysis shows no theoretical way to correct for these differences. In some circumstances, even though intensity measurements do not yield the exact directivity pattern, the differences may be acceptable.
Subject Classification: 10.60; 85.22.
An application of Poisson process models to multipath sound propagation of sinusoidal signals
Authors: Jobst William J. 
Published: October 2005

A theory of multipath sound propagation is developed in which the number of rays between a source and receiver is modeled as a Poisson distributed random variable. Using probability distributions obtainable from environmental measurements and acoustic ray tracing programs, moments of the received sound field are derived as functions of space and time. An example is presented in which spatial and temporal coherence are estimated for a horizontal line array. It is shown that spatial coherence decreases with increasing angle from broadside, with increasing frequency, with increasing source speed, and with increasing ray vertical arrival angle at the receiver. Temporal coherence decreases with increasing source speed, with increasing ray vertical angle at the source, and with increasing frequency.
Subject Classification: 20.20; 30.20; 60.20.
Nonlinear resonances in a class of multi-degree-of-freedom systems
Authors: Sridhar S. , Nayfeh A. H. , Mook D. T. 
Published: October 2005

An analysis is presented of the superharmonic, subharmonic, and combination resonances in a multi-degree-of-freedom system which has cubic nonlinearity and modal viscous damping and is subject to harmonic excitation. It is shown that in the absence of internal resonances, the steady-state response contains only the modes which are directly excited. It is shown that in the presence of internal resonances, modes other than those that are directly excited can appear in the response. The strong influence of internal resonances is exhibites in numerical examples involving hinged–clamped beams. It is shown that when a multimode solution exists the lowest mode can dominate the response, even when it is not directly excited.
Subject Classification: 40.30, 40.20.
Aircraft community noise research and development; a historical overview
Authors: Blumenthal V. L. , Russell R. E. , Streckenbach J. M. 
Published: October 2005

The paper summarizes noise-reduction research and development programs of The Boeing Company from the early 1950s to the present time. It discusses the background for each program and presents the end results obtained or progress made. Acoustic treatments are described that permit all current Boeing turbofan†powered commercial aircrafdt models to comply with applicable U.S. Government and international noise rules. Benefits attainable through noise-abatement operating procedures are included. The paper concludes with a discussion of unsolved problems that need attention by the scientific community to permit continuing reductions in aircraft noise.
Subject Classification: 50.40, 50.50, 50.55, 50.75.
Nose-reduction programs for DC-8 and DC-9 airplanes
Authors: Frasca R. L. 
Published: October 2005

A summary review is presented of the results of current and recently completed noise-reduction programs for DC-8 and DC-9 airplanes. The relationship of these programs to other efforts by Douglas to develop quieter CTOL airplanes is briefly outlined. The engine/nacelle concepts studied were (1) application of nacelle acoustic treatment, (2) variable-area exhaust nozzles, (3) jet exhaust noise suppressors, and (4) engines with larger diameter new front fans. Acoustic analyses leading to the selection of certain engine/nacelle configurations are described, as well as design constraints which limit the noise-reduction capability of certain designs. Acoustic design features of the modified engine/nacelles are discussed along with estimates of the changes in aircraft community noise levels, as well as estimates of the changes in aircraft weight, performance, cost, and operational restrictions. The noise-reduction estimates for the DC-8 and DC-9 are based on ground runup and flyover noise tests. Comments are presented on the potential noise-reduction benefits, and associated aircraft operational problems, resulting from noise-abatement operating procedures.
Subject Classification: 50.40, 50.50, 50.30, 50.55, 50.75.
Loudness enhancement: monaural, binaural, and dichotic
Authors: Elmasian Robert , Galambos Robert 
Published: October 2005

When one tone burst (Tc) precedes another (S1) by 100 msec, variations in the intensity of Tc systematically influence the loudness of S1. When Tc is more intense than S1, S1 is increased; and when Tc is less intense, S1 loudness is decreased. This occurs in monaural, binaural, and dichotic paradigms of signal presentation. When Tc and S1 are presented to the same ear (monaural or binaural) there is more enhancement with less intersubject variability than when they are presented to different ears (dichotic paradigm). Monaural enhancements as large as 30 dB can readily be demonstrated but decrements rarely exceed 5 dB. Possible physiological mechanisms are discussed for this loudness enhancement, which apparently shares certain characteristics with time-order error, assimilation, and temporal partial masking experiments.
Subject Classification: 65.50, 65.62.
Effects of high-pass filtering and of extraneous low-frequency energy on measurements of wall-pressure correlation functions
Authors: Mulhearn P. J. 
Published: October 2005

The effects of extraneous high-frequency energy and of high-pass filtering to eliminate it on measurements of turbulent wall-pressure fluctuations are investigated using a model spectrum. It is concluded that under normal conditions, while the overall shape of the correlation functions is not greatly affected by these modest adjustments at low frequencies, changes in correlation values of the order of 50% will result at only moderatly large time delays or spatial separations.
Subject Classification: 28.65; 85.32; 60.20.
Aerodynamic noise from motor vehicles
Authors: Chanaud Robert C. , Muster Douglas 
Published: October 2005

In motor vehicles there are two primary sources of aerodynamic sound: the engine-cooling fan and the interaction of either the entire vehicle or some of its components with the airstream created by vehicle movement. The mechanisms for sound generated by these sources are discussed in terms of the associated physical parameters (fan size, fan-blade design, cooling-air velocity and path, etc.; body configuration, interior design, etc.).
Subject Classification: 10.60; 50.50, 50.55.
Tire–road interaction noise
Authors: Leasure William A. , Bender Erich K. 
Published: October 2005

The relative importance of tire noise to overall vehicle noise is established. A general description is then given of the tire engineering process and of tire structures. The important parameters influencing tire noise are discussed, based on presently available data, followed by an identification of unknown and contradictory areas. The basic mechanisms of tire-noise generation, although not well understood, are investigated largely from a theoretical viewpoint. Areas for future research and development are identified based on gaps in the existing physical data base and a rather primitive level of understanding of noise-generating mechanisms.
Subject Classification: 10.60; 50.50, 50.30.
Focusing properties of a solid four element ultrasonic lens
Authors: Folds D. L. , Hanlin J. 
Published: October 2005

A multielement cylindrical lens fabricated from polystyrene and an unfilled silicone polymer has been developed with angular resolution in the order of 0.2 deg at 1000 kHz. Theoretical and experimental work shows the lens maintains good performance over a 20-deg field of view with insignificant temperature-induced defocusing in the 10 ° to 25 °C temperature range. Tolerance analyses completed during the lens design resulted in reasonable mechanical tolerances being required during fabrication.
Subject Classification: 30.85; 35.80.
Acoustic radiation from surfaces oscillating at large amplitude and small Mach number
Authors: Frost P. A. , Harper E. Y. 
Published: October 2005

The purpose of this paper is to demonstrate that at small values of the Mach number a harmonically rich radiated field will result from the simple harmonic (sinusoidal) motion of an oscillating body when the amplitude of oscillation is large. An asymptotic solution of the equations of inviscid compressible flow is obtained which is valid in the small Mach number limit. To a given order of approximation, the effects of fluid nonlinearity (nonlinearity in the equations of motion and the equation of state) do not enter, and the harmonic distortion is due entirely to large-amplitude boundary motion. In higher approximations, where both the effects of boundary motion and fluid nonlinearity enter, the former effect can still control the amplitude of certain harmonics of the radiated acoustic field. The results are obtained by the method of matched asymptotic expansions, which is ideally suited for the purpose of distinguishing the harmonic distortion due to large displacements from that due to fluid nonlinearity. The method is used to make the connection between the field far from the source, and the nonpropagating hydrodynamic flow field near the oscillating body.
Subject Classification: 25.55; 20.15, 20.60.
Masking of tone by tone as a function of duration
Authors: Jeffress Lloyd A. 
Published: October 2005

Consideration of a proposed electrical model of monaural detection leads to the suggestion that subjects listening to long-duration signals may respond on the basis of amplitude peaks. To eliminate such peaks, a 500-Hz tone was employed as both masker and signal. A two-interval, forced-choice procedure was used to determine the level required for 80% correct at each of several signal durations. The masker level was 60 dB SPL, and the signal was always in phase with the masker. Signal durations from 20 msec to 2 sec were employed. The results showed a slope of approximately −3 dB per doubling over the range from 20 msec to 1 sec. Detection at 2 sec tended to be worse than at 1 sec. The slope of 03 dB per doubling is steeper than has commonly been found with noise maskers, especially at the longer durations. The psychometric function exhibites a systematic change of slope with duration—steep for short durations and shallow for long.
Subject Classification: 65.35, 65.58, 65.75.
Speech perception by the chinchilla: discrimination of sustained ‖a‖ and ‖i‖
Authors: Burdick Charles K. , Miller James D. 
Published: October 2005

Four chinchillas were trained to respond differently to sustained ‖a‖ and ‖i‖. The ensemble of vowels included two repetitions of each of the vowels by each of four talkers at each of three pitch levels for a total of 24 ‖a‖’s and 24 ‖i‖’s. The sound levels of the vowels were randomly changed from trial to trial over a 10-dB range. The animals easily transferred the training to a new set of vowels produced by 24 new talkers. Subsequently, the animals similarly transferred to synthetic ‖a‖’s and ‖i‖’s. The only relevant difference between the synthetic vowels was their formant structure, while there were irrelevant differences in their pitch contours. We conclude that the chinchilla can abstract some essential difference(s) between sustained ‖a‖ and ‖i‖ and ignore irrelevant variations of sound level, pitch level, pitch contour, and voice quality. These results are discussed in terms of perceptual learning and auditory concept formation.
Subject Classification: 70.30; 65.75; 80.50.
On the front cavity resonance and its possible role in speech perception
Authors: Kuhn G. M. 
Published: October 2005

Spectrographic data are presented which suggest that it may be possible to estimate the frequency of the fundamental resonance of the cavity behind the mouth opening, the ’’front cavity resonance,’’ from information in the speech signal. It is shown that place of articulation information in the steady states, transitions, and bursts of F2 (or sometimes F3) can be reinterpreted to be information from the front cavity resonance. Furthermore, a number of synthesis results that have appeared anomalous when described in terms of numbered formants seem to find a coherent explanation in terms of the front cavity resonance. Implications for theories of speech perception include the possibility that an estimate of front cavity resonance frequency may serve for continuous articulatory reference.
Subject Classification: 70.20, 70.30.
Sound absorption measurements at 10–60 kHz in near-freezing sea water
Authors: Garrison G. R. , Francois R. E. , Pence E. A. 
Published: October 2005

Sound propagation measurements at various frequencies between 10 and 60 kHz were made in April 1974 under the pack ice near Pt. Barrow, Alaska. With a stationary transmitter at mid-depth, a series of sound level versus depth profiles at ranges between 40 and 1300 m were obtained and used to calculate the absorption coefficient. Although the sound speed profile contained many small irregularities which caused undesirable fluctuations, it had no large features that would change the average intensity at the ranges and depths at which the sound was received. The average temperature and salinity were −1.6 °C and 32.3 0/00, respectively. The calculated absorption values in decibels per kiloyard were 2.5±0.5 at 10 kHz, 4.5±0.5 at 20 kHz, 8.3±0.5 at 30 kHz, 10.7±0.4 at 40 kHz, and 13.9±0.5 at 60 kHz. These values indicate a relaxation frequency, assumed due to MgSO4, of 27±5 kHz, a value much lower than that predicted by the Schulkin–Marsh equation, but about the same as that determined by Greene in similar low-temperature water.
Subject Classification: 30.20, 30.80; 35.24.
Simulation of multicorrelated random processes using the FFT algorithm
Authors: Wittig L. E. , Sinha A. K. 
Published: October 2005

A technique for the digital simulation of multicorrelated Gaussian random processes is described. This technique is based upon generating discrete frequency functions which correspond to the Fourier transform of the desired random processes, and then using the fast Fourier transform (FFT) algorithm to obtain the actual random processes. The main advantage of this method of simulation over other methods is computation time; it appears to be more than an order of magnitude faster than present methods of simulation. One of the main uses of multicorrelated simulated random processes is in solving nonlinear random vibration problems by numerical methods of simulation. One of the main uses of multicorrelated simulated random integration of the governing differential equations. The response of a nonlinear string to a distributed noise input is presented as an example. nonlinear string to a distributed noise input is presented as an example.
Subject Classification: 45.40; 40.30, 40.22, 40.35.
Perceptual space for musical structures
Authors: Miller James R. , Carterette Edward C. 
Published: October 2005

Individual subjects with or without musical training made similarity judgments of pairs of tones on a nine-point scale. Each subject was run in three or four sessions of 351 trials each. The tones had structures like those of musical instruments, being made of all 27 combinations of three dimensions, each at three levels. In Experiment 1, the dimensions were fundamental frequency F0, envelope, and relative amplitudes of harmonics. In Experiment 2, the dimensions were number of harmonics, envelope, and onset rate of harmonics. Analysis of data by means of multidimensional scaling showed a strong context effect. In Experiment 1, F0 had such high saliency that for most subjects no other dimension was present in perceptual space and thus no differences were found between musical and nonmusical subjects. By holding F0 constant in Experiment 2, subjects were able to use harmonic as well as envelope structure in judgments. Differences between musical and nonmusical subjects appeared, and we discuss the basis for these differences. For both experiments, the curve relating latency of response to similarity was parabolic and, although a given subject’s perceptual space changes little over successive runs, there is some evidence from Experiment 2 that musical subjects have the more stable space of perceptual dimensions.
Subject Classification: 65.52, 65.75; 75.10.
Amplitude behavior of the cubic difference tone
Authors: Schroeder M. R. 
Published: October 2005

The nonlinearity of the basilar membrane motion observed by Rhode can be accounted for by assuming that the linear losses (proportional to the membrane velocity) are supplemented by nonlinear losses—particularly losses proportional to the velocity raised to the third power. In this paper, the consequences of such a nonlinear-loss law for the combination tone 2f1−f2 (the lower ’’cubic difference tone,’’ DCT) are examined. In agreement with experimental data, the amplitude of the CDT is found to approach a cube-root dependence on the primary stimulus amplitudes when the two primary amplitudes are varied proportionally. When one primary amplitude is held fixed, the calculated CDT-amplitude goes through a maximum when the other primary amplitude is increased—again as observed experimentally. In the model, this noteworthy amplitude behavior is a direct consequence of the cube-root dependence of the membrane velocity on pressure for large pressures which has an amplitude limiting action on the generation of the CDT. The basic properties of the CDT, as primary amplitudes and frequencies are varied, can be approximated by assuming that the 2f1−22 distortion component is generated predominantly at one place (near the characteristic place for f2).
Subject Classification: 65.26, 65.56.