Showing papers in "Applied Acoustics in 1984"

TL;DR: In this paper, a computer program for the determination of the impulse response of rooms, using the mirror image method, has been developed for acoustical planning of auditoria and the simulation of sound fields.

TL;DR: In this article, the same splitting of degenerate modes can occur in rectangular orthotropic plates having a certain length/width ratio due to coupling between longitudinal and transverse strain, which might be called Poisson coupling.

TL;DR: New data is presented which supplements the knowledge base and a sill and reveal design guide is proposed for the purpose of increasing the sound transmission loss of windows or light panels.

TL;DR: In this article, a field study has been performed which assessed the effectiveness of two warning sounds under realistic factory conditions and found that the intentional horn warning sound was not entirely reliable as a warning, even at levels substantially above its masked threshold, and observed more than double the adverse effect of wearing hearing protection.

TL;DR: In this article, a magnetostrictive ferrite transducer was used to estimate the radiated high power sound intensity from the maximum weight of a spherical object that can be levitated.

TL;DR: In this article, a multivariable control of rotating machines is proposed, which measures all shakers to sensor transfer functions to give a shaker transfer function matrix, M (f).

TL;DR: This paper suggests a numerical method, based on a ray-tracing technique, in which the concepts inherent in Keller's theory of diffraction are included, and the results of some simulation examples are reported.

TL;DR: The results of a social survey on noise perception in residential areas are in good agreement with the above findings, indicating that 89 per cent of people interviewed were substantially disturbed by traffic noise as discussed by the authors.

TL;DR: In this article, the advantages of a uni-polar half-cycle sine wave test signal are discussed and compared with those of a bi-Polar single-cycle signal, as well as signal requirements and analysis options for objective measures involving integrated energy.

TL;DR: In this article, a computer-ray tracing model is proposed to evaluate the sound absorption coefficient, based on the characterization of the reverberant room by its own "calibration curve", which enables these phenomena to be described and operatively defines the randomization strength of room design.

TL;DR: In this paper, the authors present a summary of experiments in which performers used a range of devices, under live concert conditions, to tune stage acoustics, and present a detailed discussion of the reasons for providing devices that enable them.

TL;DR: In this paper, the authors discuss the practical aspects of heat pump installations which are important in determining the sound levels produced; namely, the selection of the heat pump, its siting and the use of enclosures and silencers.

TL;DR: In this article, the membership companies of the German Federation of Chemical Industry have recorded 230 noise complaints from 1977 to 1979, and parameters, e.g., nature of noise source, noise character, time of noise occurrence, meteorological conditions, were investigated and statistically evaluated.

TL;DR: In this article, the long-term average spectrum of Spanish, as spoken in Mexico, was obtained for thirty subjects, fifteen men and fifteen women, using a digital system comprised of an FFT analyzer interfaced to a microcomputer.

TL;DR: In this article, an approximate solution to the title problem for the following situations is presented: (a) supported and clamped rectangular plates, (b) circular plates with edges elastically restrained against rotation, and (c) beams with ends flexibly attached.

TL;DR: In this paper, Wood Wool Cement Slabs have been compared with the expected behaviour based on laboratory measurements of absorption coefficients or sound reduction indices, and field results are shown for comparison where these are available.

TL;DR: In this article, random combinations of up to ten sine waves have been considered and the distribution of the resultant amplitudes obtained, and the results show that the resulting amplitudes are similar to the ones obtained in the real world.

TL;DR: In this paper, the authors describe a simple method for the calculation of changes in noise levels generated by the vehicle population of a country as a whole in future time related to present population.

TL;DR: A general review of legislation and test standards relating to construction noise, covering both the emission and immission standards is provided.

TL;DR: In this paper, a discrepancy between formulae for room acoustics, published in books, journals and national and international regulations, led the author to a compatible definition of modified absorption area.

TL;DR: In this paper, a new trial of statistical prediction for the stochastic insulation effect of a sound barrier is proposed in a special case where the insulation system parameters have to be improved, especially from a methodological viewpoint.

TL;DR: In this article, an approximate solution is obtained in the case of a beam with ends elastically restrained against rotation and an intermediate support, where a sinusoidally varying excitation is assumed.

TL;DR: In this paper, the Ritz method is used for non-homogeneous continuous media and it is shown that it is convenient for this complicated type of structural element, which is of great interest in many fields, from geophysics to everyday mechanical engineering systems.

TL;DR: In this article, the authors used the Ritz method and approximated the deflection function by means of polynomial co-ordinate functions which satisfy the essential boundary conditions, such as the presence of an axial force and concentrated masses.

TL;DR: In this article, the authors investigated whether any such difference exists and suggested that the result is more likely a function of the techniques of survey and analysis adopted in the Hong Kong study, based on a statistical comparison of the regression lines and on an examination of the problems associated with transferring an annoyance scale developed in one environment to another.

TL;DR: In this paper, the response of structural components excited by turbulent flow noise depends on the natural resonance frequencies and displacement modes of those components, and an experimental program was described which determined those resonance frequency and modes for a flat plate clamped in the middle of its four sides and also for the case when one of the four bolts had failed.

TL;DR: Results from the computer are compared with manual results and good agreement is observed and a listing of the computer program is BASIC is given.

TL;DR: In this paper, simple analogous circuits derived from Biot theory were used to predict the acoustical properties of low flow resistance and very high flow resistance foams, and compared with the predicted ones.

TL;DR: In this paper, an experimental assessment of both conventional absorption and Bragg scattering techniques for the reduction of noise transmission by a fan in a short, low velocity duct connecting two reverberant rooms is presented.