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Prescoring based upon the material contained in abstracts was used to allocate presentation times for the papers in Speech Communication submitted for presentation at the 80th Meeting of the Acoustical Society. After the papers were actually presented, their technical content, presentation quality, and discussion quality were judged. No casual relationships could be established between the prescoring and postjudging of the paper, although the papers allocated 15 min were judged statistically better in technical content than the papers allocated 5 or 10 min. It is hoped that this letter might entice others to conduct further experimentation and subjective assessment of different methods for improving professional meetings. [ABSTRACT FROM AUTHOR]

It has been previously determined that precompressed onionskin paper may be used as an acoustic decoupler. In our evaluation, compressional-wave measurements were made on various types of paper, and in particular onionskin typing paper, at 32 and 1000 kHz. At the lower frequency, a composite material technique was used to allow pressurization of the samples. The velocity of sound and attenuation were found to vary nonlinearly with pressure over the range from 0 to 2000 psi. This nonlinearity introduces a nonlinear acoustic loading of the transducer elements and is the main disadvantage of onionskin paper. However, it was confirmed that the onionskin paper should be more stable with pressure than the other papers, provided that it has been properly precompressed. Most of the insertion loss provided by onionskin paper is caused by the mismatch in acoustic impedance. Thus, a fairly wide variety of materials should provide equivalent acoustical properties. [ABSTRACT FROM AUTHOR]

The acoustic decoupling behavior of onionskin paper is examined, with emphasis on sonar transducer applications. Nonlinear changes in the sound velocity of onionskin paper with pressure are used to predict the degradation of both frequency and directional response. These results are obtained by computer analysis of a longitudinal-vibrator equivalent circuit. The results are in reasonable agreement with the measured characteristics of a specific transducer configuration. [ABSTRACT FROM AUTHOR]

This paper is a reply to views on aircraft noise in the community and in the passenger cabin of modern jet aircraft presented in three papers at the 86th Meeting of the Acoustical Society in Los Angeles, Nov. 1973 (Papers MM1, MM3, and MM11). It is argued that procedures used by the author of paper MM-1 can result in EPNL values subject to errors of as much as 8 to 15 EPN dB. Recent measurements by Boeing are quoted that are substantially in agreement with those officially determined in 1971 for 727 aircraft on take-off. It is anticipated that landing noise will show similar agreement with published data. Other Boeing measurements using an aircraft in which engine noise was essentially eliminated indicate that it is technologically impossible to achieve the low community noise levels suggested in MM3 at the present time with a viable commerical airplane. Measurements together with widely accepted hearing conservation criteria indicate that travellers are not being exposed to hazardous noise levels inside passenger cabins of modern jets as claimed in paper MM11. [ABSTRACT FROM AUTHOR]

The recent paper by Hueter et al. on ultrasonic lesions in the central nervous system, which appeared in a recent issue of this Journal (March, 1956), presents a rather limited view of this field and may lead to some misunderstandings. This note is a critical analysis of the Hueter paper. Some of the more important points discussed are: (1) The unique advantages of producing ultrasonic lesions in the brain by using dosages appropriate for selective action combined with focusing of the beam in contrast to the use of focusing alone. (2) The choice of an irradiation procedure in experiments designed for the elucidation of physical mechanisms of the action of ultrasound on tissue. (3) The specification of the acoustic variables required for a dosage description. (4) The inapplicability of Eyring's theory of viscosity, plasticity, and diffusion to the elucidation of observed dosage relations. (5) The clarification of the usage of the terminology, nontemperature effects. (6) The applicability of the reciprocity method for the calibration of thermo-couple probes. [ABSTRACT FROM AUTHOR]

Critiques by A. Cohen, H. Davis, B. L. Lempert, and W. D. Ward of my paper 'Impairment to Hearing from Exposure to Noise' are treated individually. Questions raised by the reviewers are discussed and areas for further discussion are noted. [ABSTRACT FROM AUTHOR]

A program for computer retrieval of papers in acoustics is being used to search titles of all papers that have appeared in four journals over the past 13 years. Title words and author surnames are truncated to five letters. The search may be weighted Boolean, fractional, or for associated words needed to formulate a request. [ABSTRACT FROM AUTHOR]