摘要:

A public demonstration of a rudimentary speech processing system consisting of a speech analyzer, language translator, type decoder, and speech synthesizer was given at the Meeting of the Acoustical Society of America in New York, May 23–26, 1962. Each word spoken into the microphone was analyzed, converted to a syllable code, transmitted as a syllable code, synthesized to speech, or converted to the typed page either in the same language or other languages. The two language inputs were English and French, the synthesized speech outputs were English, French, and Spanish and the typed outputs were English, French, German, and Spanish.

ISSN:0001-4966    

DOI:10.1121/1.1909035

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

A method is presented for increasing the aperture of solid, polygonal delay lines based on the method of linear programming. If it is assumed that there is no spreading of energy so that the acoustic beam may be defined by two parallel lines, the radii of the polygon can be computed which result in the maximum value of the aperture (the distance between the parallel lines) for fixed angles, subject to the constraints of the problem. Small variations in the angles which lead to a further increase the aperture can also be computed by linear programming. In addition, the method can be applied if the beam is assumed to spread in a linear fashion.

ISSN:0001-4966    

DOI:10.1121/1.1909037

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

The acoustic intensity absorption coefficient of tissue of the central nervous system has been determined at the sound frequency of 1 Mc/sec in the temperature range from 2° to 28°C at incident sound intensities ranging from 5 to 200 W/cm2. The absorption coefficient exhibits an increase with increasing temperature and no variation with the acoustic intensity.

ISSN:0001-4966    

DOI:10.1121/1.1909039

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

A theory is developed for the diffraction of light by ultrasonic waves of sufficiently high frequency, large amplitude, and/or large beamwidth that the emerging light wavefront is significantly amplitude modulated in addition to the phase modulation considered in the Raman‐Nath approach. The ultrasonic beam is considered to consist ofNadjacent sections and the final diffraction spectrum to result fromNsuccessive diffractions. The diffraction orders emerging from a given section are considered to be sources for further diffraction by the next section. Only phase modulation of the separate plane waves (diffraction orders) is considered within a section. Refraction of light is not considered as such; it is characterized by successive redistribution of light in the diffraction orders. Numerical results are obtained by iterations using an electronic computer. These results are compared with measurements.

ISSN:0001-4966    

DOI:10.1121/1.1909041

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

By using some approximations it is possible to get fairly simple approximate formulas for the number of resonance frequencies and for the point impedance of thin cylinders. Measurements of the resonance frequencies and of the number of resonances within a certain frequency range confirm the theoretical results.

ISSN:0001-4966    

DOI:10.1121/1.1909043

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

The performance of an array is affected by the interaction of the array elements; this interaction is expressed as a radiation impedance. The radiation impedance for a circular piston in an infinite planar array is calculated as a function of distance between elements and the angle to which the array is steered.

ISSN:0001-4966    

DOI:10.1121/1.1909045

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

The influence of loading of a test item on a rigid shock‐Machine platform was investigated to determine whether any peaks or notches are introduced into the acceleration shock spectrum which would cause excessive over or under testing at various frequencies. The results showed that the shock spectrum for a terminal peak saw tooth pulse is quite insensitive to shock‐machine loading. The very low frequency end (below 100 cps for a 6‐msec pulse) is most influenced, whereas the higher frequencies are virtually not influenced at all. The results also showed that even for a very high loading condition the primary spectrum is in all cases less severe than the residual spectrum.Curves have been generated to depict both the primary and the residual spectrum for various resonators to shock platform mass ratios, for the case of a terminal peak saw‐tooth pulse. This particular shock pulse is of interest since the resulting shock spectrum satisfies the requirements of a number of U.S. Air Force missile electronic equipment specifications.

ISSN:0001-4966    

DOI:10.1121/1.1909047

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

A cross‐sectional taper is described which provides a bar with the possibility of uniform stress in longitudinal oscillation. It is shown that this kind of motion is a special case of a more general kind of motion in which it is possible by properly terminating the bar to make the displacement and the stress functions related polynomials of any desired order. A theory which describes the behavior of the bar in longitudinal motion is presented and compared with the results of experiment.

ISSN:0001-4966    

DOI:10.1121/1.1909049

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

An elastic energy method is presented for finding the fundamental torsional vibration frequency of solid rectangular beams without boundary constraints. A Rayleigh‐Ritz method is employed, and the results, which were calculated on an IBM 650 computer, are shown. Also illustrated is the effect a change in the Poisson's ratio of the beam material has on the fundamental frequency. A comparison is made with results of torsional vibration tests performed at the National Bureau of Standards. This comparison indicates that the analytical method employed gives fairly accurate results.

ISSN:0001-4966    

DOI:10.1121/1.1909051

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP

摘要:

An experimental investigation has been made of a transducer‐reflector combination consisting of a 90° conical reflector with a line transducer placed along the axis. Both far field and near‐field data indicate that, except at low frequencies, when a uniform line is used, the radiation patterns are equivalent to those from a uniform circular aperture. Evidently other effects compensate for the geometrical shading. By a suitable choice of line‐element connection, however, a shaded aperture distribution can be obtained. The horn reflector increases the sensitivity of the transducer but not to the extent predicted from the geometry. The interaction of elements composing the line transducer is increased by the addition of the conical reflector.

ISSN:0001-4966    

DOI:10.1121/1.1909053

出版商:Acoustical Society of America    

年代:1962

数据来源: AIP