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Generation and Propagation of Finite‐Amplitude Waves in Flexible Tubes

L. Bjørnø
1972 Journal of the Acoustical Society of America  
--Enough is known about the acoustical cues in speech to enable highly intelligible synthesis from simple algorithms, but, in most cases, the most valid expressions of cues from the point of view of perception  ...  An iterative feature analysis of transmitted information revealed that in both the Miller and Nicely [J. Acoust. Soc.  ...  A few approximate treatments are described to derive in closed form the acoustic impedance of horns.  ... 
doi:10.1121/1.1981915 fatcat:myat5hj4e5cg7iyohppoasomty

A coupled bispectral, temporal and spatial coherence function of the pressure field, scattered from a moving sea surface

Christian Bjerrum‐Niese, Leif Bjo/rno/
1995 Journal of the Acoustical Society of America  
Scope of SI: Standards, specifications, methods of measurement and test and terminology in the field of physical acoustics including architectural acoustics, electro-acoustics, sonics and ultrasonics,  ...  methods of measurement and test, and terminology in the fields of mechanical shock and physiological acoustics, including aspects of general acoustics, shock, and vibration which pertain to biological  ...  gradients in the near field.  ... 
doi:10.1121/1.414267 fatcat:gtdrkztuvfbova3a4rdj2f7umu

Sound‐pressure level distribution in a long, narrow hallway: Measurements versus results from a computer model with scattering from surface roughness and diffraction

Lily M. Wang, Jonathan Rathsam, Claus L. Christensen, Jens H. Rindel
2005 Journal of the Acoustical Society of America  
The low acoustic impedance of the foam showed a transmission coefficient near unity.  ...  The low acoustic impedance of the foam permits the propagation of infrasound through the walls of the windscreen with a transmission coefficient near unity.  ...  Here, Green's theorem is applied to analytically model the field reflected off the vibrating ground in the presence of surface Blind deconvolution ͑BDC͒ and blind source separation ͑BSS͒ are active research  ... 
doi:10.1121/1.4785653 fatcat:vcvuciqds5cztjto3gadvh6rtm

Neural network modeling of a dolphin's sonar discrimination capabilities

Lars N. Andersen, A. René Rasmussen, Whitlow W. L. Au, Paul E. Nachtigall, Herbert Roitblat
1994 Journal of the Acoustical Society of America  
The sound field scattered by a smooth thin elastic shell immersed in fluid arises largely from specular reflection and acoustic-membrane coupling, unless both source and observer are located near or on  ...  the shell.  ...  Experiments suitable for the measurement of throat impedance and directivity of acoustic horns were designed and implemented using an axisymmetric exponential and tractfix horn.  ... 
doi:10.1121/1.410770 fatcat:ioiiov6bmjdi7kiflait5dhdfe

Neural network modeling of a dolphin's sonar discrimination capabilities

Whitlow W. L. Au, Lars N. Andersen, A. René Rasmussen, Herbert L. Roitblat, Paul E. Nachtigall
1995 Journal of the Acoustical Society of America  
The sound field scattered by a smooth thin elastic shell immersed in fluid arises largely from specular reflection and acoustic-membrane coupling, unless both source and observer are located near or on  ...  the shell.  ...  Experiments suitable for the measurement of throat impedance and directivity of acoustic horns were designed and implemented using an axisymmetric exponential and tractfix horn.  ... 
doi:10.1121/1.413700 pmid:7608403 fatcat:m3nunzs4wfflhfl27n4shdn2n4

On fatigue life under stationary Gaussian random loads

Ramesh Talreja
1973 Engineering Fracture Mechanics  
A unique technique, involving cross correlation between the near-field pressure and the far-field sound measured by the boom mounted microphone, yielded significant information on the distribution of acoustic  ...  with a layer of liquid crystals the intensity distribution of the ultrasonic field will be visualized.  ...  Emphasis is placed on the change in acoustic power and near-field levels due to their combined effect.  ... 
doi:10.1016/0013-7944(73)90064-7 fatcat:eue2d6byvre4zczgb7qi5np5vi

On Fatigue Life Under Stationary Gaussian Random Loads

R. Talreja
1973 Journal of the Acoustical Society of America  
A unique technique, involving cross correlation between the near-field pressure and the far-field sound measured by the boom mounted microphone, yielded significant information on the distribution of acoustic  ...  with a layer of liquid crystals the intensity distribution of the ultrasonic field will be visualized.  ...  Emphasis is placed on the change in acoustic power and near-field levels due to their combined effect.  ... 
doi:10.1121/1.1982256 fatcat:w7xnxse54nerdlhsueme325zem

Modeling and experiments with low‐frequency pressure wave propagation in liquid‐filled, flexible tubes

Cato Bjelland, Leif Bjo/rno/
1992 Journal of the Acoustical Society of America  
New nonlinear effects are uncovered: a nonlinear self-defocusing of the beam and an alteration of the near-field structure of the harmonic components. 9:50 IAEA4.  ...  The pressure amplitude distributions of the five first harmonic components, along and across the acoustic axis, are presented and discussed.  ...  The total acoustic pressure is measured as a hologram on a cylindrical surface concentric to and in the near field of the shell.  ... 
doi:10.1121/1.404777 fatcat:xhmwz65h5bbqxbt52khae2rq7q

Treatment of early and late reflections in a hybrid computer model for room acoustics

Graham Naylor
1992 Journal of the Acoustical Society of America  
New nonlinear effects are uncovered: a nonlinear self-defocusing of the beam and an alteration of the near-field structure of the harmonic components. 9:50 IAEA4.  ...  The pressure amplitude distributions of the five first harmonic components, along and across the acoustic axis, are presented and discussed.  ...  The total acoustic pressure is measured as a hologram on a cylindrical surface concentric to and in the near field of the shell.  ... 
doi:10.1121/1.404930 fatcat:xeehcxepjvhuzmnaeudpqxtnvu

Predicting room acoustical behavior with the ODEON computer model

Graham Naylor, Jens Holger Rindel
1992 Journal of the Acoustical Society of America  
New nonlinear effects are uncovered: a nonlinear self-defocusing of the beam and an alteration of the near-field structure of the harmonic components. 9:50 IAEA4.  ...  The pressure amplitude distributions of the five first harmonic components, along and across the acoustic axis, are presented and discussed.  ...  The total acoustic pressure is measured as a hologram on a cylindrical surface concentric to and in the near field of the shell.  ... 
doi:10.1121/1.404931 fatcat:z4hbezklfzgu7hyy7qvos3wyo4

Discrimination of short speech‐like formant transitions

Astrid van Wieringen, Louis C. W. Pols
1992 Journal of the Acoustical Society of America  
New nonlinear effects are uncovered: a nonlinear self-defocusing of the beam and an alteration of the near-field structure of the harmonic components. 9:50 IAEA4.  ...  The pressure amplitude distributions of the five first harmonic components, along and across the acoustic axis, are presented and discussed.  ...  The total acoustic pressure is measured as a hologram on a cylindrical surface concentric to and in the near field of the shell.  ... 
doi:10.1121/1.405128 fatcat:dbtewzqvijhkta6op7ul3ribti

Three-dimensional point-cloud room model in room acoustics simulations

Milos Markovic, So/ren K. Olesen, Dorte Hammersho/i
2013 Journal of the Acoustical Society of America  
It suggests a promising way in the computation of sound power and near field acoustic holography.  ...  Based on the relationship between the mapped radiation modes of a vibrating structure and its field sound pressure distribution patterns on a sphere, an improved near field acoustic holography is also  ...  As illustrative examples, the energybased MCMC algorithms are applied to the problem of filter design as used in human head-related transfer functions and in acoustic impedance boundaries within the finite-difference  ... 
doi:10.1121/1.4806371 fatcat:ln4w6j7cjvchrckf2gzfmeiwoi

Influence of statistical surface models on dynamic scattering of high‐frequency signals from the ocean surface

Christian Bjerrum‐Niese, Leif Bjo/rno/
1994 Journal of the Acoustical Society of America  
The sound field scattered by a smooth thin elastic shell immersed in fluid arises largely from specular reflection and acoustic-membrane coupling, unless both source and observer are located near or on  ...  the shell.  ...  Experiments suitable for the measurement of throat impedance and directivity of acoustic horns were designed and implemented using an axisymmetric exponential and tractfix horn.  ... 
doi:10.1121/1.411137 fatcat:ajwj7bozxzg6fd27v4xe57drgm

Gemination in Italian: the GEMMA project

Maria‐Gabriella Di Benedetto
2000 Journal of the Acoustical Society of America  
a near-field measurement of the pressure ͑electric field͒, as is done in near-field acoustical holography.  ...  The problem of reconstructing acoustic source distributions from field measurements is very often ill-posed.The use of Tikonhov regularization, for example, often suppresses the effect of small singular  ...  In the conformal near-field acoustical holography ͑NAH͒, using the boundary element method ͑BEM͒, the vibroacoustic information on the source surface can be indirectly reconstructed by utilizing the measured  ... 
doi:10.1121/1.4743263 fatcat:obqdn75v75agre5yrl3zvndhce

Scattering by two spheres: Theory and experiment

Irina Bjo/rno/, Leif Bjo/rno/
1998 Journal of the Acoustical Society of America  
No far-field constraints are imposed in the derivation of the method, allowing the measurements to be conducted within the geometric near-field of the body.  ...  Due to the comparatively wide range of density and wave velocity materials of acoustic impedance ranging from 0.2 Ϫ1ϫ10 6 Pa•s/m can be produced.  ...  This results in a simple relationship between the complex acoustic scatter and the one-component, three-dimensional Fourier transform of the temperature field measured at the scattering producing Fourier  ... 
doi:10.1121/1.421626 fatcat:qf2u35fztjfgtgredwhbg53zwm
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