Showing papers in "Applied Acoustics in 1983"

TL;DR: A computer program is described which displays the space, time and directional distribution of energy in a room and has been used in room acoustical planning and in the design of sound reinforcement systems.

TL;DR: In this paper, the acoustic protection of a balcony open to the street but enclosed on all other sides was investigated by means of one-tenth scale models, and the results indicated that the protection is slight and the frequency invariant when the receiver is exposed to a direct path.

TL;DR: In this article, the effects of roof pitch on reverberation time and sound propagation in four factories with panel roofs, when empty and/or fitted, are discussed. But the effect of roof pitches on factory SP is complicated.

TL;DR: The work of Jordan and other groups involved in acoustic modelling of auditoria is reviewed briefly with a discussion of the scale factors used and the nature of testing as mentioned in this paper, concluding in each case with an assessment of the level of contribution each can make to auditorium design.

TL;DR: In this paper, the subjective response to noise is predicted as a function of measured predicted sound levels, and linear regression analyses are performed between noise exposure and dissatisfaction response, which is correlated to the individual respondent's reaction.

TL;DR: In this paper, the variation in the sound reduction index as a function of the size of a test specimen was investigated and five different sizes of one particular hinged window were tested with a sound insulating double glazing and a laminated pane mounted in normal wooden frames.

TL;DR: In this article, the determination of natural frequencies of transverse vibrations of simply supported, clamped, and clamped-simply supported beams with an intermediate support subject to an axial force was dealt with.

TL;DR: The importance of measuring the waterborne sound emission is stressed and a simplified test procedure is recommended in this paper, which is particularly suited for use in noisy environments such as are frequently found in industry.

TL;DR: In this paper, the authors investigate the effect of valve noise on flow control valve measurements and on automatic flow control in pipes, based on Lighthill's acoustic analogy and Curle's theory for noise generation from fluid-solid boundary interactions.

TL;DR: In this article, a mathematical model of sound propagation and attenuation in factories has been developed on certain simplifying assumptions and the interrelationship between the different parameters is found to be rather intricate and the mathematical model must be evaluated using a computer program.

TL;DR: In this article, the acoustic performance of perforated screens of unusual geometry was investigated by means of model work and computer simulation resulting from diffraction theory in which the barrier produces an amplitude gradient (thnadner) or a phase gradient (splitter).

TL;DR: In this paper, the authors describe circuits for applying the carrier modulation process, and discuss the hierarchy of choices for the methods used, including varactors, which are suitably biased solid-state diodes and transistors usually used to provide capacitance reactances.

TL;DR: This paper gives various examples illustrating the fact that the equivalent noise level will be considerably reduced by changing the traffic composition, which shows that the town-planner can use various strategies to change the traffic compositions in order to achieve quieter city environments.

TL;DR: In this paper, a measuring system based on the definition of coherence coefficient and some examples applying the system to acoustic measurement are discussed in addition, the measured values agree well with the theoretical ones.

TL;DR: In this article, a Mesapparatur zur bestimmung des Anteils seitlich auftreffenden Schalls sowohl in realen Raumen als auch in Modellen im Masstab 1:50 vorgestellt is presented.

TL;DR: In this article, the authors proposed new criteria for good auditorium acoustics, which take into account the details of human perception of sound, as well as the physics of sound propagation, such as the temporal and directional distribution of reflected sounds received binaurally.

TL;DR: In this article, a simple procedure for correcting the measured reverberation time and the related program, implemented on a Texas Instruments T1-59 personal calculator, are presented, which can be used to check the decay rate of sound within large enclosures.

TL;DR: In this paper, a doorless enclosure of two three-sided interlocking rectangular barriers was found to produce attenuation of over 9 dB, and computer studies were carried out to simulate the experimental results.

TL;DR: In this paper, a simplified field method of measuring the aggregate adverse deviation of a partition is proposed to rate partitions according to the criterion specified in the British building regulations, which can also be applied to situations which use a different grading curve such as the grading curve for flats in Scotland.

TL;DR: It is suggested that the advantages of two schools of thought in subjective measurement methods in auditorium acoustics could be combined to derive a reliable subjective measure for evaluating auditoria in the field.

TL;DR: In this paper, a simple form of test for airborne sound insulation could involve generating a broad band pink noise in the source room and measuring the source and receiving room levels with a meter containing frequency weighting networks.

TL;DR: In this article, a simple, flexible computer procedure which can aid the acoustic designer in selecting the absorbing treatments needed to fit the reverberation time/frequency curve of an enclosure between assigned limits is described.

TL;DR: The results of this bit compression/usable information preservation scheme reduce the task of pattern recognition of personality parameters to a manageable one both in a data size and in a processing time sense.

TL;DR: In this paper, a novel system of weighing articles, which can be used by totally blind persons, is described, based on the acoustic effects experienced by a membrane under tension and subjected to sonic radiations.

TL;DR: In this article, a new methodology was developed for the problem of sound propagation above ground, where the respective advantages of pure tones generated by a pressure driver with a λ 4 tube and impulsive noises issued from an 8 mm alarm pistol with a double cavity absorbing silencer were analyzed.

TL;DR: In this article, the reverse problem of decomposing a net distribution into its constituent parts is discussed and information is presented which allows estimation of the variance of a constituent distribution, given the residual and net distributions.

TL;DR: In this article, a simple polynomial co-ordinate function and the Ritz method are used to solve the title problem for circular plates of uniform thickness and the algorithm yields very accurate results in the case of circular plates with uniform thickness.

TL;DR: In this paper, the influence of advancing the opening point and increasing the advance-outlet port width is shown by means of the pressure fluctuations measured in the exhaust silencer and their frequency analyses.

TL;DR: In this article, the behavior patterns of staircase dynamic response to structure-borne sound are given through analysis of two-dimensional models, which include angular discontinuities which represent the intersection line between the horizontal slabs and the stair's slope.