Searched for: mods_originInfo_publisher_s%3A%22Acoustical%255C+Society%255C+of%255C+America%22
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Yaitskova, N. (author), Van de Kuilen, J.W.G. (author)
Time-of-flight is a time for an ultrasonic pulse to cross a sample. It contains valuable information about the mechanical properties of a material. For the ultrasonic pulse propagating in wood perpendicular to the grain the relation between the time-of-flight and the elastic constants is rather complex due to the strong anisotropicity of wood....
journal article 2014
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Wapenaar, C.P.A. (author), Thorbecke, J.W. (author), Van der Neut, J.R. (author), Broggini, F. (author), Slob, E.C. (author), Snieder, R. (author)
The methodology of Green’s function retrieval by cross-correlation has led to many interesting applications for passive and controlled-source acoustic measurements. In all applications, a virtual source is created at the position of a receiver. Here a method is discussed for Green’s function retrieval from controlled-source reflection data,...
journal article 2014
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Fan, H. (author), Smeulders, D.M.J. (author)
Borehole waves are strongly affected by adjacent porous zones or by fractures intersecting the borehole. A theoretical description for both porous and fracture zones is possible based on the introduction of an effective borehole fluid bulk modulus, characterizing the wave attenuation via borehole wall impedance. This impedance can be calculated...
journal article 2013
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Fricke, J.T. (author), El Allouche, N. (author), Simons, D.G. (author), Ruigrok, E.N. (author), Wapenaar, C.P.A. (author), Evers, L.G. (author)
The atmospheric wind and temperature can be estimated through the traveltimes of infrasound between pairs of receivers. The traveltimes can be obtained by infrasonic interferometry. In this study, the theory of infrasonic interferometry is verified and applied to modeled stratospherically refracted waves. Synthetic barograms are generated using...
journal article 2013
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Snellen, M. (author), Eleftherakis, S. (author), Amiri-Simkooei, A. (author), Koomans, R.L. (author), Simons, D.G. (author)
This contribution presents sediment classification results derived from different sources of data collected at the Dordtse Kil river, the Netherlands. The first source is a multi-beam echo-sounder (MBES). The second source is measurements taken with a gamma-ray scintillation detector, i.e., the Multi-Element Detection System for Underwater...
journal article 2013
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Verweij, M.D. (author), Demi, L. (author), Van Dongen, K.W.A. (author)
Nonlinear ultrasound is important in medical diagnostics because imaging of the higher harmonics improves resolution and reduces scattering artifacts. Second harmonic imaging is currently standard, and higher harmonic imaging is under investigation. The efficient development of novel imaging modalities and equipment requires accurate simulations...
journal article 2013
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Van Dongen, K.W.A. (author), Ozmen-Eryilmaz, N. (author)
Tomogrophic ultrasound imaging is gaining popularity in breast cancer detection. Reconstructing the acoustic properties of a breast from the ultrasound measurements is stated as a nonlinear inverse problem, which is usually solved by linearized methods because of computational efficiency. However, linearization of the problem reduces the quality...
conference paper 2013
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Ozmen-Eryilmaz, N. (author), Van Dongen, K.W.A. (author)
Tomogrophic ultrasound imaging is gaining popularity in breast cancer detection. Reconstructing the acoustic properties of a breast from the ultrasound measurements is stated as a nonlinear inverse problem, which is usually solved by linearized methods because of computational efficiency. However, linearization of the problem reduces the quality...
conference paper 2013
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Van Dorp Schuitman, J. (author), De Vries, D. (author), Lindau, A. (author)
Acousticians generally assess the acoustic qualities of a concert hall or any other room using impulse response-based measures such as the reverberation time, clarity index, and others. These parameters are used to predict perceptual attributes related to the acoustic qualities of the room. Various studies show that these physical measures are...
journal article 2013
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Kroesen, M. (author), Molin, E.J.E. (author), Van Wee, G.P. (author)
In applied research, noise annoyance is often used as indicator of subjective reaction to aircraft noise in residential areas. The present study aims to show that the meaning which respondents attach to the concept of aircraft noise annoyance is partly a function of survey context. To this purpose a survey is conducted among residents living...
journal article 2013
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Eleftherakis, D. (author), Amiri-Simkooei, A. (author), Snellen, M. (author), Simons, D.G. (author)
Riverbed and seafloor sediment classification using acoustic remote sensing techniques is of high interest due to their high coverage capabilities at limited cost. This contribution presents the results of riverbed sediment classification using multi-beam echo-sounder data based on an empirical method. Two data sets are considered, both taken at...
journal article 2012
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Wapenaar, C.P.A. (author), Douma, H. (author)
The generalized optical theorem is an integral relation for the angle-dependent scattering amplitude of an inhomogeneous scattering object embedded in a homogeneous background. It has been derived separately for several scalar and vectorial wave phenomena. Here a unified optical theorem is derived that encompasses the separate versions for...
journal article 2012
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Lorenzoni, V. (author), Ragni, D. (author)
An experimental study of the flow inside a saxophone mouthpiece in playing conditions is carried out by means of particle image velocimetry at high acquisition rate. Planar velocity measurements on the midsection of a Plexiglas tenor saxophone mouthpiece are performed, respectively, in the mouthpiece baffle and in the reed channel. Sequences of...
journal article 2012
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Zhubayev, A. (author), Ghose, R. (author)
A careful look into the pertinent models of poroelasticity reveals that in water-saturated sediments or soils, the seismic (P and S wave) velocity dispersion and attenuation in the low field-seismic frequency band (20–200 Hz) have a contrasting behavior in the porosity-permeability domain. Taking advantage of this nearly orthogonal behavior, a...
journal article 2012
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Taal, C.H. (author), Henriks, R.C. (author), Heusdens, R. (author), Jensen, J. (author)
Existing objective speech-intelligibility measures are suitable for several types of degradation, however, it turns out that they are less appropriate in cases where noisy speech is processed by a time-frequency weighting. To this end, an extensive evaluation is presented of objective measure for intelligibility prediction of noisy speech...
journal article 2011
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Taal, C.H. (author), Hendriks, R.C. (author), Heusdens, R. (author), Jensen, J. (author)
Existing objective speech-intelligibility measures are suitable for several types of degradation, however, it turns out that they are less appropriate in cases where noisy speech is processed by a time-frequency weighting. To this end, an extensive evaluation is presented of objective measure for intelligibility prediction of noisy speech...
journal article 2011
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Van Neer, P.L.M.J. (author), Danilouchkine, M.G. (author), Verweij, M.D. (author), Demi, L. (author), Voormolen, M.M. (author), Van der Steen, A.F.W. (author), De Jong, N. (author)
In medical ultrasound, fundamental imaging (FI) uses the reflected echoes from the same spectral band as that of the emitted pulse. The transmission frequency determines the trade-off between penetration depth and spatial resolution. Tissue harmonic imaging (THI) employs the second harmonic of the emitted frequency band to construct images....
journal article 2011
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Horchens, L. (author)
Flexural waves play a significant role for the radiation of sound from plates. The analysis of flexural wave fields enables the detection of sources and transmission paths in plate-like structures. The measurement of these wave fields can be carried out indirectly by means of near-field acoustic holography, which determines the vibrational wave...
journal article 2011
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Van Dalen, K.N. (author), Drijkoningen, G.G. (author), Smeulders, D.M.J. (author), Heller, H.K.J. (author), Glorieux, C. (author), Sarens, B. (author), Verstraeten, B. (author)
The interface-wave impedance and ellipticity are wave attributes that interrelate the full waveforms as observed in different components. For each of the fluid/elastic-solid interface waves, i.e., the pseudo-Rayleigh (pR) and Stoneley (St) waves, the impedance and ellipticity are found to have different functional dependencies on Young’s modulus...
journal article 2011
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Van Dalen, K.N. (author), Drijkoningen, G.G. (author), Smeulders, D.M.J. (author)
At the fluid/porous-medium interface the pseudo-Rayleigh (pR) and pseudo-Stoneley (pSt) waves exist. The relation with the corresponding poles in the slowness plane is not unambiguous, depending on the choice of branch cuts. For a point-force excitation, the far-field Green’s functions are computed using vertical branch cuts (method I) implying...
journal article 2011
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