ISSN:0001-4966    

DOI:10.1121/1.1909880

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

The study of binarual interaction may be conveniently divided into three areas: anatomy, physiology, and psychology. These areas, while furnishing large amounts of data, have not yet provided enough information to make possible a complete theory of binarual interaction. Several partial theories are discussed, two experiments are reported, the results of the experiments set in perspective, and the problems of the construction of a full theory of binarual interaction are presented. A Bibliography is appended.

ISSN:0001-4966    

DOI:10.1121/1.1909881

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

Ultrasonic attenuation in water vapor and heavy‐water vapor has been measured over the range of angular frequency/pressure from 10 to several hundred radian megacycles per second/atmosphere about 137°C. The resulting vibrational relaxation time at 1 atm forH2Ovapor comes out to be about(8±2.5) × 10−9 secand that inD2Ovapor to be about(7.0±1.0) × 10−9 sec.

ISSN:0001-4966    

DOI:10.1121/1.1909882

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

The problem of reflection of plane waves from transition layers in fluid media with an arbitrary, variation of velocity and density is discussed as an extension of a recent paper by the author [Geophysics30, 122–132 (1965)]. Numerical results are given for some cases of interest. It is found that the reflection coefficient is very insensitive to the precise manner in which the elastic parameters vary within the transition zone as long as both velocity and density terminate at the same values.

ISSN:0001-4966    

DOI:10.1121/1.1909883

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

A proof is given, in a form readily available to the engineer, of the uniqueness of mean‐square approximate systems. The proof is based upon the fact that weighted mean‐square error can be expressed as a simple quadratic form in normal coordinates of sample systems.

ISSN:0001-4966    

DOI:10.1121/1.1909884

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

A method of computation of natural frequencies for a closed, coupled, damped‐vibrational system of equal masses, springs, and dashpots is devised, based on a known method applicable to an equivalent undamped system. It is shown that the higher oscillatory modes are completely suppressed. The analysis is extended to a viscoelastic continuum exhibiting similar behavior.

ISSN:0001-4966    

DOI:10.1121/1.1909885

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

We present the solution for the scattered field corresponding to a plane sound wave incident upon an infinite elastic circular‐cylindrical concentric shell, imbedded in a fluid and enclosing another fluid. The results are shown to contain the known special cases of fluid and elastic solid cylinders. Furthermore, limiting expressions for long wavelengths are obtained in special cases.

ISSN:0001-4966    

DOI:10.1121/1.1909886

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

The echoes from a rigid, freely movable sphere, due to an incident train of plane waves, are computed, together with the associated rigid‐body motions of the sphere. These results are compared with those for a rigid, immovable sphere and it is shown that they differ significantly only for values ofkabelow about 5. The significance of the results in relation to previous work on sonar echoes from solid, elastic spheres in water is discussed. A particular case of forced motion of the rigid sphere, where the echoes diminish to zero at high frequencies, is also investigated.

ISSN:0001-4966    

DOI:10.1121/1.1909887

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

Under the assumption that deep‐water ocean noise is a superposition of uncorrelated plane waves, the covariance can be expressed in terms of the noise directivity. We propose a simple directivity function that agrees with experimental results and use it to study the covariance for the case of vertical receiving points. We investigate covariance versus spacing for zero time delay and various directivities and bandwidths. When almost all of the noise arrives from the horizontal, the zero‐delay covariance is always positive; when most of the noise arrives from overhead, it is negative for some spacings. We present contours of constant covariance as a function of spacing and time delay for various directivities and a narrow frequency band. We also examine covariance for single‐frequency noise. Vertical noise with steering towards the vertical and horizontal noise with steering towards the horizontal are found to give the same covariance values. We examine maximum covariance over time delay and also that delay for which maximum covariance occurs. Numerous comparisons are made between our predictions and published experimental results. Finally, covariance for horizontal receiving points is considered.

ISSN:0001-4966    

DOI:10.1121/1.1909888

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

Many expressions for the coupling factor in terms of the fundamental resonant and antiresonant frequencies have been developed. The applicability of many of these is limited, either because they have been obtained from simplified equivalent circuits, or because they apply to particular electromechanical configurations. Approaching the problem by way of the wave equation and mechanical analysis raises difficulties that can only be resolved for relatively simple cases. An approach through a generalized equivalent circuit is used to determine more‐general expressions for the coupling factor in terms of the resonant and antiresonant frequencies at the fundamental and overtone modes of vibration. Theoretical and practical applications of these expressions are presented.

ISSN:0001-4966    

DOI:10.1121/1.1909889

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP