Results 11 to 20 of about 13,594 (294)
Experimental methodology for obtaining sound absorption coefficients
Revista Facultad Nacional de Salud Pública, 2011 Objective: the authors propose a new methodology for estimating sound absorption coefficients using genetic algorithms. Methodology: sound waves are generated and conducted along a rectangular silencer. The waves are then attenuated by the absorbing material covering the silencer’s walls.
Carlos A. Macía M +1 more
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Broadening sound absorption coefficient with hybrid resonances [PDF]
Applied Acoustics, 2020 Abstract In the last years, a great research effort has been focused on the noise mitigation at low frequencies. Membrane-type acoustic metamaterials (AMM) are one of the most promising solutions to meet the growing demand for low frequency sound absorbers.
Bucciarelli, Fabrizio, Meo, Michele
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Theoretical Estimation Based on CT Images and Experiments on the Sound Absorption Coefficient of Foam Materials with Removed Membrane. [PDF]
Materials (Basel)Sakamoto S +4 more
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Investigation of the sound absorption properties of gypsum particleboard produced with kenaf stalks and nano clay [PDF]
تحقیقات علوم چوب و کاغذ ایران, 2014 In this study sound absorption coefficient and hardness of gypsum particleboard produced with kenaf stalk and nano clay were investigated. Variables in this study were weight ratio of kenaf stalks to poplar wood in three levels (40, 50 and 60 %) and nano
Hossein Rangavar, Mohammad hassan Payan
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Nihon Kikai Gakkai ronbunshu, 2021 Quantitative evaluation of uncertainty in acoustic properties is an essential issue to improve product quality. The acoustic properties of porous materials, such as sound absorption coefficient, are affected by variations in microstructure and material ...
Yosuke KOMATSU +5 more
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Sound Absorption and Diffusion by 2D Arrays of Helmholtz Resonators
Applied Sciences, 2020 We report a theoretical and experimental study of an array of Helmholtz resonators optimized to achieve both efficient sound absorption and diffusion. The analysis starts with a simplified 1D model where the plane wave approximation is used to design an ...
Iván Herrero-Durá +5 more
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Fiber Weight Fraction Effect to Acoustic Properties of RHDPE Cantula Composite
Mekanika, 2017 In this study, composites made from recycled HDPE and Cantula fiber have been done and the absorption coefficient have been measured. Composites rHDPE-Cantula were made using hot press for approximately 60 minutes with 170oC temperature while pressure ...
Muhammad Taufik Burhany Hendrowarsito +2 more
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Akytojo betono garso absorbcijos tyrimai/Porous concrete sound absorption investigation
Journal of Civil Engineering and Management, 1996 Low-density porous concrete can be used as a sound absorbing material. This paper generalizes porous concrete sound absorption investigations. Porous concrete relative wave resistance modulus is longer than air wave resistance W=1 and that is why this
Antanas Laukaitis, Vytautas Lasauskas
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ENHANCEMENT OF COIR FIBER NORMAL INCIDENCE SOUND ABSORPTION COEFFICIENT [PDF]
Journal of Computational Acoustics, 2012 Coir fiber from coconut husk is an important agricultural waste in Malaysia. The porous structure of fiber makes it an eligible material for acoustical absorption. In previous studies at Universiti Kebangsaan Malaysia, single layer coir fiber showed low acoustical absorption in medium and low frequencies; e.g.
Fouladi, M. +3 more
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Journal of Wood Science, 2021 We investigated the effect of ultrasonic treatment on Malas (Homalium foetidum) gas permeability and sound absorption coefficient using the transfer function method.
Chun-Won Kang +4 more
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