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Stability of finite difference numerical simulations of acoustic logging-while-drilling with different perfectly matched layer schemes

Hua Wang, Guo Tao, Xue-Feng Shang, Xin-Ding Fang, Daniel R. Burns
2013 Applied Geophysics  
In acoustic logging-while-drilling (ALWD) fi nite difference in time domain (FDTD) simulations, large drill collar occupies, most of the fl uid-fi lled borehole and divides the borehole fl uid into two  ...  is critical to simulate complicated wave modes accurately.  ...  Unlike wire-line acoustic logging models, in acoustic LWD FDTD simulations, large drill collar occupies most of the fl uid-fi lled borehole and divide the borehole fl uid into two thin fl uid columns (  ... 
doi:10.1007/s11770-013-0400-6 fatcat:oja4rpiz4zcznfvfhug4ttk5z4

Frequency-domain simulation of logging-while-drilling borehole sonic waveforms

Paweł J. Matuszyk, Carlos Torres-Verdín
2014 Geophysics  
Numerical simulation of sonic logging-while-drilling (LWD) borehole measurements is challenging because of significant wave propagation effects due to the massive drilling collar occupying a large portion  ...  of the borehole.  ...  We are indebted to the TACC at the University of Texas at Austin for providing high-performance computing resources that were fundamental to the completion of this research project.  ... 
doi:10.1190/geo2013-0279.1 fatcat:fpq7vtaozfdvjdlkzh7ix7by3u

Spanning the scales of mechanical metamaterials using time domain simulations in transformed crystals, graphene flakes and structured soils

Ronald Aznavourian, Tania M Puvirajesinghe, Stéphane Brûlé, Stefan Enoch, Sébastien Guenneau
2017 Journal of Physics: Condensed Matter  
Figure 7 . 7 Scheme of the 2012 field test experiment conducted by the Ménard company in Grenoble (a): an oscillating probe generates acoustic waves at 50 Hz in front of a mesh of cylindrical boreholes  ...  However, regarding numerical simulations, it is usual to use L 2 norm for error estimates, and we have checked that FDTD simulations of elastic waves propagating in morphing based medium in figure 6(a)  ... 
doi:10.1088/1361-648x/aa81ff pmid:28742059 fatcat:3ltt3qbv75f2tgc6fzlkvsh43y

Vocal fold vibratory and acoustic features in fatigued Karaoke singers

Gaowu Wang, Andy Lo, Karen Chan, Jiangping Kong, Edwin Yiu
2012 Journal of the Acoustical Society of America  
The acoustic fields excited by eccentric acoustic source in cased boreholes bonded by cements with different densities are simulated numerically using 2.5-dimension (2.5D) finite-difference method (FDM  ...  As the eccentric distance of the acoustic source reaches 1/4 of the borehole radius, the amplitude of the FA will reduce to below 20% of the centered case.  ...  One group of participants learned to segregate concurrent vowels by using difference in fundamental frequency (ƒ 0 ) while the other group learned to use difference in sound location.  ... 
doi:10.1121/1.4708731 fatcat:cu5chvstgjbzhlhdzd63flz7nu

The influence of thresholding passive bubble-acoustic signals on the quantification of physical effects

Richard Manasseh, Yonggang Zhu, Hubert Chanson, Andrew Ooi, Alexander Babanin, Irena Bobevski
2012 Journal of the Acoustical Society of America  
The acoustic fields excited by eccentric acoustic source in cased boreholes bonded by cements with different densities are simulated numerically using 2.5-dimension (2.5D) finite-difference method (FDM  ...  As the eccentric distance of the acoustic source reaches 1/4 of the borehole radius, the amplitude of the FA will reduce to below 20% of the centered case.  ...  One group of participants learned to segregate concurrent vowels by using difference in fundamental frequency (ƒ 0 ) while the other group learned to use difference in sound location.  ... 
doi:10.1121/1.4708757 fatcat:4zx4vkq66rgihgir2kv6pms4ea

Bio-inspired seismic metamaterials: Time domain simulations in transformed crystals [article]

Ronald Aznavourian, Tania Puvirajesinghe, Stephane Brule, Stefan Enoch, Sebastien Guenneau
2016 arXiv   pre-print
Experimental data extracted from field test analysis of soil structured with boreholes demonstrates the application of bio-inspired seismic metamaterials.  ...  We analyze elastic wave propagation in the transformed crystals and (Penrose-type) quasi-crystals with the finite difference time domain freeware SimSonic.  ...  However, regarding numerical simulations, it is usual to use L 2 norm for error estimates, and we have checked that FDTD simulations of elastic waves propagating in morphing based medium in Figure 8  ... 
arXiv:1611.00867v1 fatcat:2vzvbenx2bey7epi2smyeflljy

Higher order modes in acoustic logging while drilling

Shihong Chi, Zhenya Zhu, Rama Rao, M. Nafi Toksoz
2005 SEG Technical Program Expanded Abstracts 2005   unpublished
In this paper, we extend the Real Axis Integration (RAI) method and improve the Finite Difference Time Domain (FDTD) method to investigate the wave fields excited by the monopole and multipole Acoustic  ...  We simulate the two traditional kinds of source exerting methods by both of the RAI and FDTD methods accurately and efficiently.  ...  The FDTD modeling results of this paper are based on a substantial improvement on this simulator by the author.  ... 
doi:10.1190/1.2144333 fatcat:6iz7s57ahvbpjasicplbbsaezm

The results of a unique Nordic HAKK interlaboratory REAT comparison

Torben Poulsen
1999 Journal of the Acoustical Society of America  
On the accuracy of the assessment of room acoustical parameters using MLS technique and ray-tracing simulation Also, the following poster sessions are scheduled: Poster Session 3aAOa Poster Session 3aPPb  ...  As a result, males are capable of signaling acoustically over up to two km.  ...  Theoretical work and computer simulations also predict that the travel-time of acoustic signals is biased by the ocean internal wave field.  ... 
doi:10.1121/1.425267 fatcat:6pa5rsq5zjcanl55hcxmwa743u

Calculation of the A term of magnetic circular dichroism based on time dependent-density functional theory I. Formulation and implementation

Michael Seth, Tom Ziegler, Arup Banerjee, Jochen Autschbach, Stan J. A. van Gisbergen, Evert J. Baerends
2004 Journal of Chemical Physics  
In our studies we simulate simple aspects of reverberation by exploiting a well-known auditory illusion known as the precedence effect ͑PE͒.  ...  The data show a wide range of STI and Cx values for a given T, and the minimum STI at each reverberation time can be obtained by diffused field theory.  ...  Simulation of borehole acoustic measurements with adaptive finite elements for the accurate and efficient assessment of rock formation properties.  ... 
doi:10.1063/1.1747828 pmid:15268124 fatcat:hwyfald5a5f4njmw5h7p6vjhnu

A design methodology for 2D sparse NDE arrays using an efficient implementation of refracted-ray TFM

Jerzy Dziewierz, Timothy Lardner, Anthony Gachagan
2013 2013 IEEE International Ultrasonics Symposium (IUS)  
One of these technologies takes advantage of the acoustic radiation forces associated with ultrasound standing wave fields to spatially pattern cells within collagen-based hydrogels.  ...  These changes in collagen microstructure were produced using both ultrasound standing wave fields and traveling wave fields.  ...  Numerical simulations are done by the solution of the coupled heat and wave equations using the finite difference time domain (FDTD) method with a combination of implicit and explicit temporal integration  ... 
doi:10.1109/ultsym.2013.0035 fatcat:th5znfh7y5bklfdbmhb4u6iq2i

On determination of microphone response and other parameters by a hybrid experimental and numerical method

Salvador Barrera‐Figueroa, Finn Jacobsen, Knud Rasmussen
2008 Journal of the Acoustical Society of America  
Wave field synthesis utilizes a large number of loudspeakers to generate a desired wave field.  ...  This paper proposes a simulation system capable to simulate wave field synthesis systems in different rooms based on physical measurements of one loudspeaker in each room.  ...  simulator based on the finite-difference time-domain ͑FDTD͒ method was evaluated by acoustic measurements on solid models of the vocal tract.  ... 
doi:10.1121/1.2933455 fatcat:gl6kkwih6rbkriigc7g6ghdlnq

A binaural advantage in the subjective modulation transfer function with simple impulse responses

Eric R. Thompson, Torsten Dau
2008 Journal of the Acoustical Society of America  
Wave field synthesis utilizes a large number of loudspeakers to generate a desired wave field.  ...  This paper proposes a simulation system capable to simulate wave field synthesis systems in different rooms based on physical measurements of one loudspeaker in each room.  ...  simulator based on the finite-difference time-domain ͑FDTD͒ method was evaluated by acoustic measurements on solid models of the vocal tract.  ... 
doi:10.1121/1.2933699 fatcat:4nc5pg4ysbhgrjcatwhr7fh77q

The importance of bass clarity in pop and rock venues

Niels W. Adelman‐Larsen, Eric R. Thompson
2008 Journal of the Acoustical Society of America  
Wave field synthesis utilizes a large number of loudspeakers to generate a desired wave field.  ...  This paper proposes a simulation system capable to simulate wave field synthesis systems in different rooms based on physical measurements of one loudspeaker in each room.  ...  simulator based on the finite-difference time-domain ͑FDTD͒ method was evaluated by acoustic measurements on solid models of the vocal tract.  ... 
doi:10.1121/1.2932922 fatcat:fvtlbt6x5vgelp5p67x53qtvgi

Acoustic source identification in an enclosed space using the inverse phased beam tracing at medium frequencies

Jeong‐Guon Ih, Cheol‐Ho Jeong
2008 Journal of the Acoustical Society of America  
and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the  ...  public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL  ...  Simulation of wave field synthesis.  ... 
doi:10.1121/1.2933749 fatcat:xiro7xkminfl5o3psp2ejziawq

2005 Index

2005 IEEE Transactions on Geoscience and Remote Sensing  
Discrete Fourier transforms FDTD methods eccentric LWD tool response, boreholes, dipping forms., 3D simul.  ...  ., T-GRS Dec 05 2778-2792 gravity wave momentum flux, spectrosc. imaging, estim. Jing Tang, + , T-GRS Jan 05 103-109 SUBJECT INDEX A INDEX Acoustic signal processing; cf.  ... 
doi:10.1109/tgrs.2005.861474 fatcat:peucpnumgfchhhwbn665yvx7ue
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