So Small, So Loud: Extremely High Sound Pressure Level from a Pygmy Aquatic Insect (Corixidae, Micronectinae)

The high sound pressure level generated by impulse noise produced in an indoor shooting range makes it necessary to protect the hearing of the people it affects. Due to the need for verbal communication during training at a shooting range, level-dependent hearing protectors are useful. The objective of this study was to answer the question of whether it is possible to properly protect the hearing of a shooting instructor using level-dependent hearing protectors. The noise parameters were measured in the places where the instructor was present at the shooting range. The division of a specific group of trained shooters into subgroups consisting of three or six simultaneously shooting individuals did not significantly affect the exposure of the shooting instructor to the noise. An assessment of noise reduction was carried out for eight models of earmuffs and two variants of earplugs, using computational methods for the selection of hearing protectors. Among the noise parameters, both the A-weighted equivalent sound pressure level and the C-weighted peak sound pressure level were taken into account. Depending on the assessment criterion adopted, a sufficient reduction in impulse noise was provided by either four or six out of the 10 hearing protectors included in the study.

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Contributions of Voice and Nonverbal Communication to Perceived Masculinity–Femininity for Cisgender and Transgender Communicators

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-19-00387 ◽

2020 ◽

Vol 63 (4) ◽

pp. 931-947

Author(s):

Teresa L. D. Hardy ◽

Carol A. Boliek ◽

Daniel Aalto ◽

Justin Lewicke ◽

Kristopher Wells ◽

...

Keyword(s):

Fundamental Frequency ◽

Sound Pressure Level ◽

Sound Pressure ◽

Vocal Tract ◽

Presentation Mode ◽

Pressure Level ◽

Presentation Modes ◽

Audiovisual Stimuli ◽

Vocal Tract Resonance ◽

Point Light

Purpose The purpose of this study was twofold: (a) to identify a set of communication-based predictors (including both acoustic and gestural variables) of masculinity–femininity ratings and (b) to explore differences in ratings between audio and audiovisual presentation modes for transgender and cisgender communicators. Method The voices and gestures of a group of cisgender men and women ( n = 10 of each) and transgender women ( n = 20) communicators were recorded while they recounted the story of a cartoon using acoustic and motion capture recording systems. A total of 17 acoustic and gestural variables were measured from these recordings. A group of observers ( n = 20) rated each communicator's masculinity–femininity based on 30- to 45-s samples of the cartoon description presented in three modes: audio, visual, and audio visual. Visual and audiovisual stimuli contained point light displays standardized for size. Ratings were made using a direct magnitude estimation scale without modulus. Communication-based predictors of masculinity–femininity ratings were identified using multiple regression, and analysis of variance was used to determine the effect of presentation mode on perceptual ratings. Results Fundamental frequency, average vowel formant, and sound pressure level were identified as significant predictors of masculinity–femininity ratings for these communicators. Communicators were rated significantly more feminine in the audio than the audiovisual mode and unreliably in the visual-only mode. Conclusions Both study purposes were met. Results support continued emphasis on fundamental frequency and vocal tract resonance in voice and communication modification training with transgender individuals and provide evidence for the potential benefit of modifying sound pressure level, especially when a masculine presentation is desired.

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Influence of the Acoustic Reflex on Vowel Recognition

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.2903.420 ◽

1986 ◽

Vol 29 (3) ◽

pp. 420-424 ◽

Cited By ~ 4

Author(s):

Michael Dorman ◽

Ingrid Cedar ◽

Maureen Hannley ◽

Marjorie Leek ◽

Julie Mapes Lindholm

Keyword(s):

Auditory System ◽

Sound Pressure ◽

Dynamic Range ◽

Recognition Accuracy ◽

Pressure Level ◽

Acoustic Reflex ◽

The Poor ◽

Stapedial Reflex ◽

Vowel Recognition ◽

High Sound

Computer synthesized vowels of 50- and 300-ms duration were presented to normal-hearing listeners at a moderate and high sound pressure level (SPL). Presentation at the high SPL resulted in poor recognition accuracy for vowels of a duration (50 ms) shorter than the latency of the acoustic stapedial reflex. Presentation level had no effect on recognition accuracy for vowels of sufficient duration (300 ms) to elicit the reflex. The poor recognition accuracy for the brief, high intensity vowels was significantly improved when the reflex was preactivated. These results demonstrate the importance of the acoustic reflex in extending the dynamic range of the auditory system for speech recognition.

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Computers and Electronics in Agriculture The sensor to estimate the sound pressure level in eggs

Qeios ◽

10.32388/7x11uf ◽

2020 ◽

Author(s):

Iran Oliveira Silva

Keyword(s):

Sound Pressure Level ◽

Sound Pressure ◽

Pressure Level

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Case study: Theoretical calculation model and variable condition analysis research on the water-splashing noise for natural draft wet cooling towers

Noise Control Engineering Journal ◽

10.3397/1/376812 ◽

2020 ◽

Vol 68 (2) ◽

pp. 137-145

Author(s):

Yang Zhouo ◽

Ming Gao ◽

Suoying He ◽

Yuetao Shi ◽

Fengzhong Sun

Keyword(s):

Theoretical Model ◽

Sound Pressure Level ◽

Water Droplet ◽

Water Distribution ◽

Sound Pressure ◽

Cooling Tower ◽

Distribution Patterns ◽

Calculation Model ◽

Pressure Level ◽

Cooling Towers

Based on the basic theory of water droplets impact noise, the generation mechanism and calculation model of the water-splashing noise for natural draft wet cooling towers were established in this study, and then by means of the custom software, the water-splashing noise was studied under different water droplet diameters and water-spraying densities as well as partition water distribution patterns conditions. Comparedwith the water-splashing noise of the field test, the average difference of the theoretical and the measured value is 0.82 dB, which validates the accuracy of the established theoretical model. The results based on theoretical model showed that, when the water droplet diameters are smaller in cooling tower, the attenuation of total sound pressure level of the water-splashing noise is greater. From 0 m to 8 m away from the cooling tower, the sound pressure level of the watersplashing noise of 3 mm and 6 mm water droplets decreases by 8.20 dB and 4.36 dB, respectively. Additionally, when the water-spraying density becomes twice of the designed value, the sound pressure level of water-splashing noise all increases by 3.01 dB for the cooling towers of 300 MW, 600 MW and 1000 MW units. Finally, under the partition water distribution patterns, the change of the sound pressure level is small. For the R s/2 and Rs/3 partition radius (Rs is the radius of water-spraying area), when the water-spraying density ratio between the outer and inner zone increases from 1 to 3, the sound pressure level of water-splashing noise increases by 0.7 dB and 0.3 dB, respectively.

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