摘要:

The Burgers equation of fluid dynamics is applied to the problem of weak shock propagation in an anharmonic solid. For the crystalline solids KCl, Cu, and Ge, it is shown that the magnitude ofA333333/G3333is more than large enough to ensure steady compressive weak‐shock propagation. For amorphousSiO2, however,A333333is of such a sign that only weak steady rarefactions will form shocks.

ISSN:0001-4966    

DOI:10.1121/1.1910044

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

The blast wave from buried explosions consists primarily of a pulse induced by the ground shock followed by another pulse when the explosive gases are vented to the atmosphere. The latter pulse provides the dominant contribution for the shallower burial depths. Air‐blast measurements made along the ground surface for 46 chemical explosive and 7 nuclear explosive detonations have shown the peak overpressure of the ground‐shock‐induced pulse to be about the same for chemical and nuclear explosions in basal rock as for chemical explosions in alluvial soil. The ground‐shock‐induced pulse has not been observed for nuclear explosions in soil. The peak overpressure from venting gases is about equal for chemical explosives in basalt rock and alluvial soil. Peak overpressures are higher for nuclear explosions in soil, in part because the cavity pressures at the time of venting are higher; peak overpressures are lower for nuclear explosions in rock, presumably because less gas is formed and because the pulse from venting gas coincides with the negative phase following the ground‐shock‐induced pulse, thus reducing overpressure amplitude. Measurements have been made over a sufficiently large range of charge burial depths that a pattern of air‐blast suppression with charge burial can be presented.

ISSN:0001-4966    

DOI:10.1121/1.1910045

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

A technique is presented for estimating finite‐amplitude effects for standing acoustic waves. The method consists of equating the nonlinear energy loss from the fundamental mode of oscillation to the work done on this mode by its higher harmonics. The higher harmonics are determined by the assumption that the wave‐form is a sawtooth. Results are obtained for the limiting amplitude of oscillation, which are in qualitative agreement with previous results where these are available. The problems considered are (1) propagation of simple waves; (2) sound produced by a piston in a closed tube; (3) sound resulting from acoustic instability in a closed tube; (4) sound produced by a piston in a closed tube with the even harmonics strongly damped; and (5) sound resulting from acoustic instability in a closed tube with the even harmonics strongly damped.

ISSN:0001-4966    

DOI:10.1121/1.1910046

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

Reference is made to the assumptions necessary in order to test a two‐state threshold model by an experiment using confidence ratings. It is argued that the testing of such a model by, aYES NOexperiment also involves corresponding assumptions. If these are taken a justified, then the fact that both types of experiment have been shown to give similar values of false‐alarm rate for a similar detection rate establishes that the appropriate assumption for an experiment with confidence ratings is justified. Consequently, either a two‐state threshold model cannot be tested by either type of experiment or it is legitimately tested by both.

ISSN:0001-4966    

DOI:10.1121/1.1910047

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

An apparent paradox involving the size of the necessary time difference between dichotic events for a midline auditory image is partially resolved by the fact that the initiation of a so‐called timing signal in an ear is a function of the spectrum and intensity of the acoustic stimulus.

ISSN:0001-4966    

DOI:10.1121/1.1910048

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

It is well known that all pickup arms that are commercially available show some tracking error, except for one or two points of the stylus path. A geometrical analysis is given of the conditions in which a stylus will track perfectly at each point of its path. The construction principle of such a pickup arm is briefly outlined.

ISSN:0001-4966    

DOI:10.1121/1.1910049

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

Tonal spectra of wind instruments are sometimes estimated using passive‐filter theory, or the principle of linear superposition. Experiments are described that illustrate the inadequacy of such calculations. Small changes in air‐column frequencies and of the damping of these resonances can lead to large changes in the generated sound spectrum.

ISSN:0001-4966    

DOI:10.1121/1.1910050

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

This Letter considers an approximation for the acoustic response of a rectangular receiving aperture to a similarly aligned coaxial rectangular source. Graphical results for the response versus aperture separation are given for two cases.

ISSN:0001-4966    

DOI:10.1121/1.1910052

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

The potential of a circular source, having radially symmetrical but otherwise arbitrary distributionv(r0) of velocity over its face, is expanded asψ = z −1e ikR(a0+a1z−1 + ⋯)[cylindrical coordinates (r,θ,z); center of source atr − z = 0]. We finda0to depend only on the total volume velocity at the source. Ifv(r0) is known, allancan be calculated; if it is unknown, limits onancan be set.

ISSN:0001-4966    

DOI:10.1121/1.1910053

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP

摘要:

Equations are derived for the calculation of first‐order (scattering out of a mode)and second order (scattering into a mode) scattering corrections to the usual normal mode solutions. A simplified calculation illustrates the method and shows that, in special cases, sound scattering at the boundaries will cause significant changes in the propagating modes.

ISSN:0001-4966    

DOI:10.1121/1.1910054

出版商:Acoustical Society of America    

年代:1966

数据来源: AIP