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Book Application of Magnitude Estimation Scaling to the Assessment of Subjective Loudness Response to Simulated Sonic Booms

Download or read book Application of Magnitude Estimation Scaling to the Assessment of Subjective Loudness Response to Simulated Sonic Booms written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-30 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: A laboratory study was conducted for the following reasons: (1) to investigate the application of magnitude estimation scaling for evaluating the subjective loudness of sonic booms; and (2) to compare the relative merits of magnitude estimation and numerical category scaling for sonic boom loudness evaluation. The study was conducted in the NASA LeRC's sonic boom simulator and used a total of 80 test subjects (48 for magnitude estimation and 32 for numerical category scaling). Results demonstrated that magnitude estimation was a practical and effective method for quantifying subjective loudness of sonic booms. When using magnitude estimation, the subjects made valid and consistent ratio judgments of sonic boom loudness irrespective of the frequency of presentation of the standard stimulus. Presentation of the standard as every fourth stimulus was preferred by the subjects and is recommended as the standard presentation frequency to be used in future tests. Mcdaniel, S. and Leatherwood, J. D. and Sullivan, B. M. Langley Research Center RTOP 537-03-21-03...

Book Scientific and Technical Aerospace Reports

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Loudness and Annoyance Response to Simulated Outdoor and Indoor Sonic Booms

Download or read book Loudness and Annoyance Response to Simulated Outdoor and Indoor Sonic Booms written by Jack D. Leatherwood and published by . This book was released on 1993 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Subjective Response to Simulated Sonic Booms with Ground Reflections

Download or read book Subjective Response to Simulated Sonic Booms with Ground Reflections written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-11 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Sonic Boom Simulator at NASA LaRC was used for the following: (1) quantify subjective loudness of simulated composite sonic booms, each of which was comprised of a simulated direct (non-reflected) boom combined with a simulated reflection of the direct boom; and (2) evaluate several metrics as estimators of loudness for these composite booms. The direct booms consisted of selected N-wave and minimized signatures having front-shock rise times of 3, 6, and 9 milliseconds and durations of 300 milliseconds. Delay times of the reflected booms ranged from 0 to 12 milliseconds. Subjective loudness results indicated that composite booms formed using reflections with non-zero delay times were generally rated as being less loud than composite booms containing non-delayed reflections. The largest reductions in loudness occurred when delay times were equal to the front shock rise times of the direct booms and were, in some cases, equivalent to reductions in Perceived Level of 6 to 7 dB. Results also showed Perceived Level to be an effective metric for assessing subjective loudness effects for the composite signatures. This was confirmed by statistical analysis, which showed that, for equal Perceived Level, no significant differences existed between the subjective loudness responses to composite booms containing reflections with zero delay and those containing reflections with non-zero delays. Sullivan, B. M. and Leatherwood, J. D. Langley Research Center RTOP 537-03-21-03...

Book High Speed Research Sonic Boom Volume 1

Download or read book High Speed Research Sonic Boom Volume 1 written by and published by . This book was released on 1994 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Monthly Catalog of United States Government Publications

Download or read book Monthly Catalog of United States Government Publications written by United States. Superintendent of Documents and published by . This book was released on 1993 with total page 960 pages. Available in PDF, EPUB and Kindle. Book excerpt: February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index

Book Laboratory Study of Effects of Sonic Boom Shaping on Subjective Loudness and Acceptability

Download or read book Laboratory Study of Effects of Sonic Boom Shaping on Subjective Loudness and Acceptability written by Jack D. Leatherwood and published by . This book was released on 1992 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Monthly Catalogue United States Public Documents

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1993 with total page 1790 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Effect of Sonic Boom Asymmetry on Subjective Loudness

Download or read book Effect of Sonic Boom Asymmetry on Subjective Loudness written by Jack D. Leatherwood and published by . This book was released on 1992 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NASA Langley Research Center's sonic boom apparatus was used in an experimental study to quantify subjective loudness response to a wide range of asymmetrical N-wave sonic boom signatures. Results were used to assess the relative performance of several metrics as loudness estimators for asymmetrical signatures and to quantify in detail the effects on subjective loudness of varying both the degree and direction of signature loudness asymmetry. Findings of the study indicated that Perceived Level (Steven's Mark 7) and A-weighted sound exposure level were the best metrics for quantifying asymmetrical boom loudness. Asymmetrical signatures were generally rated as being less loud than symmetrical signatures of equivalent Perceived Level. The magnitude of the loudness reductions increased as the degree of boom asymmetry increased, and depended upon the direction of asymmetry. These loudness reductions were not accounted for by any of the metrics. Corrections were determined for use in adjusting calculated Perceived Level values to account for these reductions. It was also demonstrated that the subjects generally incorporated the loudness components of the complete signatures when making their subjective judgments.

Book A New Simulator for Assessing Subjective Effects of Sonic Booms

Download or read book A New Simulator for Assessing Subjective Effects of Sonic Booms written by and published by . This book was released on 1991 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Subjective Response to Sonic Booms Having Different Shapes Rise Times and Durations

Download or read book Subjective Response to Sonic Booms Having Different Shapes Rise Times and Durations written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-11 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two laboratory experiments were conducted to quantify the subjective response of people to simulated outdoor sonic booms having different pressure signatures. The specific objectives of the experiments were to compare subjective response to sonic booms when described in terms of 'loudness' and 'annoyance'; to determine the ability of various noise metrics to predict subjective response to sonic booms; to determine the effects on subjective response of rise time, duration, and level; and to compare the subjective response to 'N-wave' sonic boom signatures with the subjective response to 'minimized' sonic boom signatures. The experiments were conducted in a computer-controlled, man-rated sonic boom simulator capable of reproducing user-specified pressure signatures for a wide range of sonic boom parameters. One hundred and fifty sonic booms representing different combinations of two wave shapes, four rise times, seven durations, and three peak overpressures were presented to 36 test subjects in each experiment. The test subjects in the first experiment made judgments of 'loudness' while the test subjects in the second experiment judged 'annoyance.' Subjective response to sonic booms was the same whether expressed in terms of loudness or in terms of annoyance. Analyses of several different noise metrics indicated that A-weighted sound exposure level and Perceived Level were the best predictors of subjective response. Further analyses indicated that, of these two noise metrics, only Perceived Level completely accounted for the effects of wave shape, rise time, and peak overpressure. Neither metric fully accounted for the effect of duration. However, the magnitude of the duration effect was small over the very wide range of durations considered. Mccurdy, David A. Langley Research Center RTOP 537-03-21-03...