Use of energy-equivalent sound pressure levels and percentile level differences to assess the impact of speech on cognitive performance and annoyance perception

This paper reviews the results of several studies on the effects of blast wave exposure on the auditory system of the chinchilla, the pig, and the sheep. The chinchillas were exposed at peak sound pressure levels of approximately 160 dB under well-controlled laboratory conditions. A modified shock tube was used to generate the blast waves. The pigs and sheep were exposed under field conditions in an instrumented hard-walled enclosure. Blast trauma was induced by the impact of a single explosive projectile. The peak sound pressure levels varied between 178 and 209 dB. All animals were killed immediately following exposure, and their temporal bones were removed for fixation and histologic analysis using light microscopy and scanning electron microscopy. Middle ears were examined visually for damage to the conductive system. There were well-defined differences in susceptibility to acoustic trauma among species. However, common findings in each species were the acute mechanical fracture and separation of the organ of Corti from the basilar membrane, and tympanic membrane and ossicular failure.

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Validation of Nanoparticle Response to the Sound Pressure Effect during the Drug-Delivery Process

Polymers ◽

10.3390/polym12010186 ◽

2020 ◽

Vol 12 (1) ◽

pp. 186 ◽

Cited By ~ 1

Author(s):

Mohamed Abbas ◽

Mohammed Alqahtani ◽

Ali Algahtani ◽

Amir Kessentini ◽

Hassen Loukil ◽

...

Keyword(s):

Drug Delivery ◽

Sound Pressure ◽

Pressure Effect ◽

Experimental Results ◽

Sound Waves ◽

Subcutaneous Injections ◽

Acrylic Plastic ◽

Sound Pressure Levels ◽

The Impact ◽

Interaction Behaviors

Intravenous delivery is the fastest conventional method of delivering drugs to their targets in seconds, whereas intramuscular and subcutaneous injections provide a slower continuous delivery of drugs. In recent years, nanoparticle-based drug-delivery systems have gained considerable attention. During the progression of nanoparticles into the blood, the sound waves generated by the particles create acoustic pressure that affects the movement of nanoparticles. To overcome this issue, the impact of sound pressure levels on the development of nanoparticles was studied herein. In addition, a composite nanostructure was developed using different types of nanoscale substances to overcome the effect of sound pressure levels in the drug-delivery process. The results demonstrate the efficacy of the proposed nanostructure based on a group of different nanoparticles. This study suggests five materials, namely, polyimide, acrylic plastic, Aluminum 3003-H18, Magnesium AZ31B, and polysilicon for the design of the proposed structure. The best results were obtained in the case of the movement of these molecules at lower frequencies. The performance of acrylic plastic is better than other materials; the sound pressure levels reached minimum values at frequencies of 1, 10, 20, and 60 nHz. Furthermore, an experimental setup was designed to validate the proposed idea using advanced biomedical imaging technologies. The experimental results demonstrate the possibilities of detecting, tracking, and evaluating the movement behaviors of nanoparticles. The experimental results also demonstrate that the lowest sound pressure levels were observed at lower frequency levels, thus proving the validity of the proposed computational model assumptions. The outcome of this study will pave the way to understand the interaction behaviors of nanoparticles with the surrounding biological environments, including the sound pressure effect, which could lead to the useof such an effect in facilitating directional and tactic movements of the micro- and nano-motors.

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Impact of a participatory program to reduce noise in a Neonatal Unit

Revista Latino-Americana de Enfermagem ◽

10.1590/s0104-11692012000100015 ◽

2012 ◽

Vol 20 (1) ◽

pp. 109-116 ◽

Cited By ~ 3

Author(s):

Nelma Ellen Zamberlan-Amorim ◽

Cristina Ide Fujinaga ◽

Vanderlei José Hass ◽

Luciana Mara Monti Fonseca ◽

Cinira Magali Fortuna ◽

...

Keyword(s):

Intervention Program ◽

Sound Pressure ◽

Statistical Tests ◽

Neonatal Unit ◽

University Hospital ◽

Sound Pressure Levels ◽

Before And After ◽

Quasi Experimental ◽

Level Of Significance ◽

The Impact

This study evaluated the impact of a participatory program to reduce noise in a neonatal intermediate care unit of a university hospital. A time-series quasi-experimental design was used, in which sound pressure levels were measured before and after the intervention was implemented using the Quest-400 dosimeter. Non-parametric statistical tests were used to compare noise with the level of significance fixed at 5%. Results showed significant reduction of sound pressure levels in the neonatal unit after the intervention program was implemented (p<0.0001). The average Leq before the intervention was 62.5dBA and was reduced to 58.8dBA after the intervention. A reduction of 7.1dBA in the average Lmax(from 104.8 to 87.7dBA) and of 30.6dBA in the average Lpeak(from 138.1 to 107.5dBA) was observed. The program was proven to be effective in significantly reducing noise levels in the neonatal unit, although levels were still more intense than recommended.

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Experimental Investigation of the Influence of the Shear Layer on Direct Combustion Noise of a Turbulent Jet Flame

Volume 4B: Combustion, Fuels and Emissions ◽

10.1115/gt2017-64467 ◽

2017 ◽

Author(s):

Holger Nawroth ◽

Christian Oliver Paschereit

Keyword(s):

Shear Layer ◽

Sound Pressure ◽

Shear Layers ◽

Combustion Noise ◽

Layer Width ◽

Jet Flame ◽

Turbulent Fluctuations ◽

Direct Combustion ◽

Sound Pressure Levels ◽

The Impact

This work presents results from experiments on direct combustion noise emitted from an unconfined, turbulent, premixed jet flame. It focuses on the influence of the shear layer and the turbulent fluctuations within this layer on the resulting noise emissions. Orifice discs of different diameter are used to change the shear layer width of the emanating jet. Using these discs, which induce and increase blockage upstream of the reaction zone, leads to significantly higher turbulent fluctuations of the velocity and subsequently to wider shear layers. As these fluctuations in the shear layer are the origin of direct combustion noise, the sound pressure levels of reacting flows increase as well. Moreover, the experiments also show the impact of the Reynolds number and equivalence ratio on noise emissions when using these discs. In general, wider shear layers yield higher sound pressure levels of the resulting combustion noise. Although amplitudes of the resulting noise emissions might differ for different conditions, the normalized sound spectra coincide proving that turbulent velocity fluctuations only govern the sound pressure levels but do not affect the shape of the resulting spectra if the geometry and fuel remain the same.

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Analysis of Impact Noise of Nail Ejection in Wire Nail Machines

Volume 7B: 17th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc99/vib-8117 ◽

1999 ◽

Author(s):

Jack Ding ◽

Ahmed Al-Jumaily ◽

Doug Wilson

Keyword(s):

Sound Pressure ◽

High Frequencies ◽

Impact Noise ◽

Press Forming ◽

Large Force ◽

Ejection Force ◽

Sound Pressure Levels ◽

High Level ◽

The Impact ◽

Punch Press

Abstract A wire nail production machine can be classified as one of the punch press machines. By nature, the production of wire nails involves the development of a series of force impulses which in turn generate various sound pressure levels with different frequencies. Typically, the machine operations generating impact noise include pressing, cutting, ejecting, wire gripping and feeding. The punch pressing is the movement of punch header to press forming the nail head. It produces a large force impulse which in turn generates a high level of impact noise and consequently high levels of ancillary impact noise such as the impact noise by the backlashes. It has been found that this type of impact noise is not necessarily the most annoying one. The impact noise generated by nail ejection, however, has been identified as one of the annoying noise components. The ejector used in a nail machine for executing the movement of nail ejection produces ringing noise at high frequencies when it is struck by the punch header in each cycle of the machine operations. This paper presents the analyses of and experiments on the ejection force impulse and the characteristics of the impact noise generated by nail ejection.

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ANALYSIS OF THE EXPERIMENTAL STUDY OF THE AXLE LATHE MACHINE VIBROACOUSTIC CHARACTERISTICS FOR WORKPLACE NOISE REDUCTION

Akustika ◽

10.36336/akustika201934104 ◽

2019 ◽

Vol 34 ◽

pp. 104-106

Author(s):

Alexander Shashurin ◽

Marat Goguadze ◽

Elkin Yuriy ◽

Konstantin Buzhinskiy

Keyword(s):

Experimental Study ◽

Theoretical Analysis ◽

Sound Pressure ◽

Cutting Tool ◽

Sound Radiation ◽

Noise Levels ◽

Sound Pressure Levels ◽

Lathe Machine ◽

The Impact ◽

Workplace Noise

The purpose of this study is to measure the octave sound pressure levels and vibrations of a stanopod lathe. A theoretical analysis of the sound pressure levels near the osteoprosche machines has been performed. The results of measurements are given. It is obtained that the levels of sound pressure at the workplace exceed sanitary standards. This suggests that the increased noise levels are due to the impact of the sound radiation of the cutting tool and the axis being machined.

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Assessing Wind Impact on Noise Level Measurements for Application in Architectural Acoustics: A Preliminary Study

Nigerian Journal of Environmental Sciences and Technology - March 2018 ◽

10.36263/nijest.2021.02.0290 ◽

2021 ◽

Vol 5 (2) ◽

pp. 413-419

Author(s):

M. Ocholi ◽

K.E. Ibe ◽

E.E. Iheonu ◽

E.E. Ameh

Keyword(s):

Wind Speed ◽

Noise Level ◽

Sound Pressure ◽

Wind Effect ◽

Average Wind Speed ◽

Architectural Acoustics ◽

Wind Speeds ◽

Sound Pressure Levels ◽

Preliminary Study ◽

The Impact

In this study, we have used wind data obtained from an earlier work covering several locations in Nigeria to estimate the possible impact of wind on sound pressure levels. Estimated Weibull parameters were used to compute the most probable wind speed, the average wind speed and the duration for which wind speed exceeds or equal the most probable speed. Adopting the proposed criteria that wind is able to strengthen or weaken sound pressure levels by 3dB depending on wind direction, the effect of wind on sound pressure level was determined. Results showed that wind effect seemed more predominant for the sub-sahelian stations such as Sokoto, Kano, and Maiduguri where the impact was found to be +/- 3dB obviously due to the characteristic high wind speeds recorded at those stations. The situation is almost the same for the midland region except that moderate impacts were found in some of the stations like Yola, Yelwa and Bauchi. However, moderate wind impacts generally characterize the Guinea Savannah and the coastal regions with the exception of Enugu with an impact of +/- 3dB. The result for Warri was found to be insignificant. It was concluded that most locations within the Nigerian environment may attain the wind conditions that would necessitate an adjustment in noise level measurements for application in architectural acoustics. In order to further validate the results of this preliminary study, it was recommended that detailed field survey where all relevant parameters such as wind speeds, wind directions and noise levels are simultaneously measured be conducted.

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Real Ear Sound Pressure Levels Developed by Three Portable Stereo System Earphones

American Journal of Audiology ◽

10.1044/1059-0889.0104.52 ◽

1992 ◽

Vol 1 (4) ◽

pp. 52-55 ◽

Cited By ~ 4

Author(s):

Gail L. MacLean ◽

Andrew Stuart ◽

Robert Stenstrom

Keyword(s):

High Frequency ◽

Sound Pressure ◽

Low Frequency ◽

Test System ◽

Output Frequency ◽

Frequency Effects ◽

Adult Men ◽

Frequency Responses ◽

Significant Difference ◽

Sound Pressure Levels

Differences in real ear sound pressure levels (SPLs) with three portable stereo system (PSS) earphones (supraaural [Sony Model MDR-44], semiaural [Sony Model MDR-A15L], and insert [Sony Model MDR-E225]) were investigated. Twelve adult men served as subjects. Frequency response, high frequency average (HFA) output, peak output, peak output frequency, and overall RMS output for each PSS earphone were obtained with a probe tube microphone system (Fonix 6500 Hearing Aid Test System). Results indicated a significant difference in mean RMS outputs with nonsignificant differences in mean HFA outputs, peak outputs, and peak output frequencies among PSS earphones. Differences in mean overall RMS outputs were attributed to differences in low-frequency effects that were observed among the frequency responses of the three PSS earphones. It is suggested that one cannot assume equivalent real ear SPLs, with equivalent inputs, among different styles of PSS earphones.

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Personal Audio System: Hearing Symptoms, Habits, and Sound Pressure Levels Measured in Real Ear and a Manikin

Journal of Speech Language and Hearing Research ◽

10.1044/2020_jslhr-19-00053 ◽

2020 ◽

Vol 63 (6) ◽

pp. 2016-2026

Author(s):

Tamara R. Almeida ◽

Clayton H. Rocha ◽

Camila M. Rabelo ◽

Raquel F. Gomes ◽

Ivone F. Neves-Lobo ◽

...

Keyword(s):

Sound Pressure ◽

Daily Basis ◽

Cross Sectional Study ◽

Normal Hearing ◽

Chi Square ◽

Cross Sectional ◽

The Real ◽

Significant Difference ◽

Sound Pressure Levels ◽

Audio System

Purpose The aims of this study were to characterize hearing symptoms, habits, and sound pressure levels (SPLs) of personal audio system (PAS) used by young adults; estimate the risk of developing hearing loss and assess whether instructions given to users led to behavioral changes; and propose recommendations for PAS users. Method A cross-sectional study was performed in 50 subjects with normal hearing. Procedures included questionnaire and measurement of PAS SPLs (real ear and manikin) through the users' own headphones and devices while they listened to four songs. After 1 year, 30 subjects answered questions about their usage habits. For the statistical analysis, one-way analysis of variance, Tukey's post hoc test, Lin and Spearman coefficients, the chi-square test, and logistic regression were used. Results Most subjects listened to music every day, usually in noisy environments. Sixty percent of the subjects reported hearing symptoms after using a PAS. Substantial variability in the equivalent music listening level (Leq) was noted ( M = 84.7 dBA; min = 65.1 dBA, max = 97.5 dBA). A significant difference was found only in the 4-kHz band when comparing the real-ear and manikin techniques. Based on the Leq, 38% of the individuals exceeded the maximum daily time allowance. Comparison of the subjects according to the maximum allowed daily exposure time revealed a higher number of hearing complaints from people with greater exposure. After 1 year, 43% of the subjects reduced their usage time, and 70% reduced the volume. A volume not exceeding 80% was recommended, and at this volume, the maximum usage time should be 160 min. Conclusions The habit of listening to music at high intensities on a daily basis seems to cause hearing symptoms, even in individuals with normal hearing. The real-ear and manikin techniques produced similar results. Providing instructions on this topic combined with measuring PAS SPLs may be an appropriate strategy for raising the awareness of people who are at risk. Supplemental Material https://doi.org/10.23641/asha.12431435

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