Single-layer graphene (SLG) was demonstrated to emit sound. The sound emission from SLG had a significant flat frequency response in the wide ultrasound range from 20 kHz to 50 kHz. SLG can produce a sound pressure level (SPL) as high as 95 dB at a distance of 5 cm with a sound frequency of 20 kHz. The SPL value is among the highest reported to date for sound-emitting devices (SEDs) based on th...

The posterior field (P) of the cat auditory cortex contains a very high proportion of neurons whose responses change non-monotonically with the sound pressure level (SPL) of tonal stimuli, leading to circumscribed frequency-SPL response areas, and it has therefore been suggested that field P may be specialized for processing of sound intensity. We demonstrate here a great diversity of response ...

background: to prevent the adverse health effects of noise pollution and to achieve the recommended standards, assessment of noise levels in the cities is essential. the aim of this study was to evaluate noise pollution levels (npls) in isfahan, iran and compare them with recommended standard values. materials and methods: a total number of 19 measurement points were selected from most congeste...

Standing waves can cause measurement errors when sound-pressure level (SPL) measurements are performed in a closed ear canal, e.g., during probe-microphone system calibration for distortion-product otoacoustic emission (DPOAE) testing. Alternative calibration methods, such as forward-pressure level (FPL), minimize the influence of standing waves by calculating the forward-going sound waves sepa...

With the increase of English teaching courses, specific vocal characteristics teachers in are studied and used as basic data for design teachers’ spatial acoustics. In order to study this problem, three different voice materials were read a anechoic room under sound intensity levels: large, medium small, respectively, so analyse equivalent continuous pressure level (SPL) frequency characteristi...

Loudness discomfort levels (LDLs) were measured in dB HL and SPL at discrete frequencies between 500 to 4000 Hz on 31 hearing-impaired ears using TDH-50P and ER-3A earphones. The results revealed no significant differences in the measured sound pressure level (SPL) between the two earphones at all test frequencies. However, with dB HL measurements, statistically significant differences were rev...

This paper studies the feasibility of acquiring the multiple source-receiver transfer functions for the prediction of pass-by noise Sound Pressure Level (SPL) of vehicles with the Fast Multipole Boundary Element Method (FMBEM). Employing measurements and simulations, the influence of frequency resolution, mesh density, mesh accuracy and solver accuracy on the computation time and on the overall...

In this paper, we demonstrate how to reduce the noise level of expanded air from pneumatic tools. Instead a muffler, propose collecting system, where expands through tube and expansion collector. We have elaborated mathematical model which illustrates dynamics flow, as well acoustic pressure at end tube. The computational results were compared with experimental data check sound pressure. Moreov...