Rapid deterioration of sound level benefits for quieter pavements in Washington state based on the on‐board sound intensity method.

2010 ◽  
Vol 127 (3) ◽  
pp. 1768-1768
Author(s):  
Tim Sexton
Keyword(s):  
Sound Intensity ◽  
Sound Level ◽  
Washington State ◽  
Rapid Deterioration

scholarly journals Analysis of Angklung Sound Intensity as a Acoustic Instrument

2017 ◽  
Vol 2 (1) ◽  
pp. 122 ◽  
Author(s):  
Rizka Silviana Hartanti ◽  
Budi Astuti
Keyword(s):  
Research Method ◽  
Sound Intensity ◽  
Sound Level ◽  
Tube Length ◽  
High Tone ◽  
Sound Level Meter ◽  
Independent Variable ◽  
Constant Distance ◽  
Low Tone ◽  
Level Meter

<p style="text-align: justify;">The purpose of this study was to analysis of angklung sound intensity. The research method is using angklung musician 2 octaves. Each consists of two tube tone that sounded from the tone of G to G ', length and diameter of the tube every tone becomes independent variable, while intensity of the sound produced becomes dependent variable. Sound intensity is measured using a Sound Level Meter is placed with a constant distance. The result showed that G tone was a low tone which had a frequency of 49.5 Hz, first tube had 21.6 cm length and 4.1 cm diameter, second tube had 10.1 cm length and 3.4 cm diameter produced the sound intensity of 90.7 dB. G’ tone was a high tone which had a frequency of 99 Hz, first tube had 10 cm length and 3 cm diameter, second tube had 5.5 cm length and 2.1 cm diameter produced the sound intensity of 99.1 dB. It can be concluded that the higher the frequency, the greater the intensity of the sound produced. The shorter tube length and the smaller tube diameter, the greater the intensity of the sound. ©2016 JNSMR UIN Walisongo. All rights reserved.</p>

An analysis of the mechanics of phonation

1965 ◽  
Vol 20 (2) ◽  
pp. 301-307 ◽  
Author(s):  
G. A. Cavagna ◽  
R. Margaria
Keyword(s):  
Sound Production ◽  
Respiratory Muscles ◽  
Sound Intensity ◽  
Sound Level ◽  
Intensity Level ◽  
Elastic Recoil ◽  
Mechanical Models ◽  
Fine Regulation ◽  
Flow Through ◽  
Work Done

The mechanical work done by the chest in phonation has been measured together with the sound intensity level. The regulation of the sound intensity is done by regulating the intrapulmonary pressure. This is achieved at high intensity levels through the activity of the respiratory muscles that, together with the elastic recoil of the chest, sustain the work of phonation. At sound intensities below a critical level an additional mechanism for changing the intensity is given by a fine regulation of the opening of the glottis, thus allowing more air to escape without contributing to sound production. The contribution of the respiratory muscles, of the chest elasticity, and of the opening of the glottis to phonation at different intensity levels depend on the degree of inflation of the chest. The efficiency of phonation, as of sound production in mechanical models, seems to increase with increasing intensity and pitch. voice production; work done by chest during phonation; mechanical models of glottis generator; subglottic pressure as a function of sound level; air flow through glottis during phonation; efficiency changes of sound production; variation of sound intensity by regulating opening of glottis; variations of the area of glottis depending on extent of elastic recoil of chest Submitted on February 10, 1964

Applications of Sound Intensity Measurements to Gas Turbine Engineering

1992 ◽  
Author(s):  
R. D. Rawlinson
Keyword(s):  
Gas Turbine ◽  
Sound Intensity ◽  
Cost Effective ◽  
Sound Level ◽  
Directional Sensitivity ◽  
Noise Sources ◽  
Offshore Installations ◽  
Practical Reality ◽  
Detailed Assessment ◽  
Level Meter

Recent advances in signal processing techniques have made the measurement of sound intensity a practical reality. The newly developed sound intensity meters can indicate both the magnitude and direction of sound. This is a major advantage over the traditional sound level meter which does not have such directional sensitivity. Sound intensity meters can, therefore, make accurate measurements under adverse conditions, such as onshore or offshore, where sound level meters may be unsuitable. This makes the detailed assessment of the sound power output of a gas turbine package, operating in the field, practicable. Individual components of a gas turbine train can be evaluated so that the dominant noise sources can be identified, thereby providing more cost effective solutions to onshore and offshore installations. This paper describes briefly the concepts of sound intensity, the current state of standards and some aspects of measurement technique. Case histories of the use of sound intensity instrumentation in a variety of situations, relevant to gas turbine engineering, will be described. This will include laboratory and field based investigations.

scholarly journals Effect of Noise Pollution Among Milling Machine Operators in North-West Nigeria.

2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Ademola James Adeyemi ◽  
Semiu Adedeji Yusuf ◽  
Abubakar Arzika Zaki ◽  
Emmanuel Akujieze
Keyword(s):  
Noise Level ◽  
Internal Combustion Engines ◽  
Occupational Safety ◽  
Sound Intensity ◽  
Noise Pollution ◽  
Sound Level ◽  
Entire Body ◽  
Formal Sector ◽  
North West ◽  
Commercial Activities

Commercial activities are mostly centralized to main markets in many towns and cities of the Northern part of Nigeria. Such central markets constitute the noisiest part of the towns. Yet, there is no evidence that the workers and traders in such markets are aware of the challenges excessive noise pollution pose to their health. This problem serves as the basis for this research, which investigated the major source of noise pollution in Kebbi central market and make recommendation to improve the wellbeing of the people in the market.The market was divided into thirteen sections based on activities. These sections were visited twice a day for two weeks to measure their sound levels. The sound level was measured with a CEM digital noise level meter with an accuracy of ±3.5dB@1KHz. Thereafter, an ergonomic observation assessment of the noisiest section was carried out. The assessment was carried out based on rapid entire body assessment (REBA) methodology. The average sound intensity in all the sections exceeded the recommended safe sound level of 40dB. However, only the sound intensity at the grain and spice milling section (89.13 dB) exceeded the noise harmfulness level of 85dB. Operators were encouraged to use ear muffs or earplugs to minimise the exposure to harmful noise level. Proper electrification of the section was also recommended to minimise the use of internal combustion engines. The findings emphasised the need for government and relevant authorities to carry out occupational safety awareness among workers in the non-formal sector of the society.

scholarly journals Neural Responses and Perceptual Sensitivity to Sound Depend on Sound-Level Statistics

2019 ◽  
Author(s):  
Björn Herrmann ◽  
Thomas Augereau ◽  
Ingrid S. Johnsrude
Keyword(s):  
Neural Activity ◽  
Prediction Error ◽  
Sound Intensity ◽  
Sound Level ◽  
Fine Tuning ◽  
Error Processing ◽  
Perceptual Sensitivity ◽  
Sound Levels ◽  
Level Statistics ◽  
Behavioral Evidence

AbstractSensitivity to sound-level statistics is crucial for optimal perception, but research has focused mostly on neurophysiological recordings, whereas behavioral evidence is sparse. We use electroencephalography (EEG) and behavioral methods to investigate how sound-level statistics affect neural activity and the detection of near-threshold changes in sound amplitude. We presented noise bursts with sound levels drawn from distributions with either a low or a high modal sound level. One participant group listened to the stimulation while EEG was recorded (Experiment I). A second group performed a behavioral amplitude-modulation detection task (Experiment II). Neural activity depended on sound-level statistical context in two different ways. Consistent with an account positing that the sensitivity of neurons to sound intensity adapts to ambient sound level, responses for higher-intensity bursts were larger in low-mode than high-mode contexts, whereas responses for lower-intensity bursts did not differ between contexts. In contrast, a concurrent slow neural response indicated prediction-error processing: The response was larger for bursts at intensities that deviated from the predicted statistical context compared to those not deviating. Behavioral responses were consistent with prediction-error processing, but not with neural adaptation. Hence, neural activity adapts to sound-level statistics, but fine-tuning of perceptual sensitivity appears to involve neural prediction-error responses.

The Influence of Underwater Sound on Marine Organisms

1980 ◽  
Vol 33 (2) ◽  
pp. 291-295 ◽  
Author(s):  
H. Suzuki ◽  
E. Hamada ◽  
K. Saito ◽  
Y. Maniwa ◽  
Y. Shirai
Keyword(s):  
High Speed ◽  
Sound Intensity ◽  
Sound Level ◽  
Marine Organisms ◽  
Sound Signal ◽  
Fish Behaviour ◽  
Underwater Sound ◽  
Migration Routes ◽  
Main Amplifier ◽  
Measurement And Analysis

As sea traffic grows, so too does the problem of the acoustic pollution of fishing grounds. This paper describes the measurement and analysis of ship-produced underwater sounds and their effect on the behaviour of certain fishes. It would seem that their influence on marine organisms is a growing problem and should not be ignored by navigators, for the sounds produced by large or high-speed vessels, or even fishing boats, can frighten fish shoals or cause them to change their migration routes.After a series of tests to measure and analyse the underwater sound, the output of submerged loud-speakers, either at sea or in an aquarium, was adjusted to ensure that the sound intensity near the fish was at the required level and the fish behaviour was carefully observed. For these experiments a hydrophone was connected to a pre-amplifier. A signal amplified by the pre-amplifier is attenuated before being sent to the main amplifier, the sound level being read directly on an indicator using the sound analysing character ‘C’. A tape recorder registers the sound signal in a flat response from 20 to 50 Hz to within 3 dB. A tracing recorder was also sometimes used and the two methods gave almost the same results.

scholarly journals Pengukuran Koefisien Absorbsi Bunyi pada Serbuk Gergaji Kayu Nyatoh (Palaquium species) sebagai Bahan Peredam

Jurnal MIPA ◽  
2014 ◽  
Vol 3 (1) ◽  
pp. 16
Author(s):  
Rizky Kurniawan Imban ◽  
As'ari . ◽  
Seni Herlina J. Tongkukut
Keyword(s):  
Grain Size ◽  
Physical Properties ◽  
Mass Density ◽  
Sound Intensity ◽  
Sound Level ◽  
Sound Level Meter ◽  
Particle Board ◽  
Level Meter ◽  
Reflection Intensity ◽  
Initial Intensity

Telah dilakukan penelitian untuk memperoleh nilai koefisien absorbsi bunyi pada papan partikel dari bahan campuran serbuk gergajian kayu nyatoh dan tepung kanji dengan variasi ukuran butir. Papan partikel dibuat dengan komposisi 50 g serbuk gergaji dan 50 g tepung kanji. Papan partikel dibuat dengan rapat massa (ρ) = 0,62 x 103 kg.m-3. Koefisien absorbsi bunyi diukur dengan menggunakan sound level meter, intensitas bunyi yang diukur antara lain intensitas bunyi yang datang, intensitas yang dipantulkan dan intensitas yang ditransmisikan. Intensitas absorbsi didapat dengan mengurangkan intensitas awal ( ) dengan intensitas transmisi ( ) dan intensitas refleksi ( ). Data yang diperoleh dibuat grafik dan dianalisis. Diperoleh hasil bahwa papan partikel yang terbuat dari campuran serbuk gergajian kayu nyatoh dan tepung kanji dengan komposisi 1:1 (sampel 3) adalah papan partikel terbaik sebagai bahan absorbsi bunyi pada penelitian ini. Papan partikel mempunyai sifat fisis: koefisien absorbsi 0,15 cm-1, intensitas refleksi 1,5 dB, intensitas absorbsi 29,45 dB dan efisiensi absorbsi 29,42 %.Research has been conducted to obtain the sound absorbtion coefficient of the particle board from the mixture of the sawdust of Nyatoh and the starch with the variation of the grain size. Particle board is made with the composition of 50 g sawdust and 50 g starch. Particle board is made with the mass density (ρ) = 0.62 x 103 kg.m-3. Sound absorbtion coefficient is measured using a sound level meter, sound intensity is measured such as the intensity of incident sound, the intensity of reflected sound and the intensity of transmitted sound. The intensity of absorbtion is obtained by reducing the initial intensity (I0) with the transmission intensity (IT) and the reflection intensity (IR). The obtained data were graphed and analyzed. The results indicated that the particle board that is made from the mixture of the sawdust of Nyatoh and the starch with the composition 1:1 (sample 3) is the best particle board as sound absorbtion material in this research. The particle board has physical properties: the absorbtion coefficient 0.15 cm-1, the reflection intensity 1.5 dB, the absorbtion intensity 29.45 dB, and the absorbtion efficiency 29.42%. t-f�5y � p ew Roman";mso-ansi-language:SV;mso-fareast-language:EN-US;mso-bidi-language: AR-SA'>Papan partikel dibuat dengan komposisi 50 g serbuk gergaji dan 50 g tepung kanji. Papan partikel dibuat dengan rapat massa (ρ) = 0,62 x 103 kg.m-3. Koefisien absorbsi bunyi diukur dengan menggunakan sound level meter, intensitas bunyi yang diukur antara lain intensitas bunyi yang datang, intensitas yang dipantulkan dan intensitas yang ditransmisikan. Intensitas absorbsi didapat dengan mengurangkan intensitas awal ( ) dengan intensitas transmisi ( ) dan intensitas refleksi ( ). Data yang diperoleh dibuat grafik dan dianalisis. Diperoleh hasil bahwa papan partikel yang terbuat dari campuran serbuk gergajian kayu nyatoh dan tepung kanji dengan komposisi 1:1 (sampel 3) adalah papan partikel terbaik sebagai bahan absorbsi bunyi pada penelitian ini. Papan partikel mempunyai sifat fisis: koefisien absorbsi 0,15 cm-1, intensitas refleksi 1,5 dB, intensitas absorbsi 29,45 dB dan efisiensi absorbsi 29,42 %.

Influence of a mono-frequency sound on bacteria can be a function of the sound-level

2016 ◽  
Author(s):  
Vijay Kothari ◽  
Chinmayi Joshi ◽  
Pooja Patel ◽  
Milan Mehta ◽  
Shashikant Dubey ◽  
...  
Keyword(s):  
Bacterial Growth ◽  
Sound Intensity ◽  
Test Tube ◽  
Sound Level ◽  
Pigment Production ◽  
Bacterial Response ◽  
Violacein Production ◽  
A Minor ◽  
Different Levels ◽  
Minor Extent

AbstractChromobacterium violaceum was subjected to sonic stimulation with 300 Hz sound, at five different levels of loudness in the range of 70 – 89.5 dB. Sonic stimulation was found to affect bacterial growth and quorum sensing regulated pigment (violacein) production significantly. Magnitude of this effect was found to be dependent on sound-level. The minimum critical difference required to cause any statistically significant change in bacterial response with respect to sound-level was found to be 13 dB. Growth of C. violaceum was affected more at lower sound intensity, whereas pigment production was affected more at higher sound intensity. Additional experiments with C. violaceum and Serratia marcescens indicated that even a silent speaker emitting no sound can alter bacterial growth and/or pigment production upto a minor extent. Size of the test tube in which bacteria are exposed to sonic stimulation, was not found to affect the results much.

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