Journal articles: 'Acoustic transfer function'

1

Ko, Hanseok. "CASA Based Approach to Estimate Acoustic Transfer Function Ratios." Journal Of The Acoustical Society Of Korea 33, no. 1 (2014): 54. http://dx.doi.org/10.7776/ask.2014.33.1.054.

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Mahroogi, Faisal O., S. Narayan, and Vipul Gupta. "Acoustic transfer function in gasoline engines." International Journal of Vehicle Noise and Vibration 14, no. 3 (2018): 270. http://dx.doi.org/10.1504/ijvnv.2018.097212.

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Narayan, S., Vipul Gupta, and Faisal O. Mahroogi. "Acoustic transfer function in gasoline engines." International Journal of Vehicle Noise and Vibration 14, no. 3 (2018): 270. http://dx.doi.org/10.1504/ijvnv.2018.10018293.

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Zhang, Jie, Richard Heusdens, and Richard Christian Hendriks. "Relative Acoustic Transfer Function Estimation in Wireless Acoustic Sensor Networks." IEEE/ACM Transactions on Audio, Speech, and Language Processing 27, no. 10 (October 2019): 1507–19. http://dx.doi.org/10.1109/taslp.2019.2923542.

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Fokin, Vladimir N., Margarita S. Fokina, James M. Sabatier, and Wheeler B. Howard. "Geoacoustic inversion via acoustic‐seismic transfer function." Journal of the Acoustical Society of America 114, no. 4 (October 2003): 2457. http://dx.doi.org/10.1121/1.4779613.

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Hamaguchi, Takashi, Tosiaki Miyati, Naoki Ohno, Masaya Hirano, Norio Hayashi, Toshifumi Gabata, Osamu Matsui, et al. "Acoustic Noise Transfer Function in Clinical MRI." Academic Radiology 18, no. 1 (January 2011): 101–6. http://dx.doi.org/10.1016/j.acra.2010.09.009.

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Funck, B., and A. Mitzkus. "Acoustic transfer function of the clamp-on flowmeter." IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control 43, no. 4 (July 1996): 569–75. http://dx.doi.org/10.1109/58.503717.

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Gu, Chen, Ulrich Mok, Youssef M. Marzouk, Germán A. Prieto, Farrokh Sheibani, J. Brian Evans, and Bradford H. Hager. "Bayesian waveform-based calibration of high-pressure acoustic emission systems with ball drop measurements." Geophysical Journal International 221, no. 1 (December 18, 2019): 20–36. http://dx.doi.org/10.1093/gji/ggz568.

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SUMMARY Acoustic emission (AE) is a widely used technology to study source mechanisms and material properties during high-pressure rock failure experiments. It is important to understand the physical quantities that acoustic emission sensors measure, as well as the response of these sensors as a function of frequency. This study calibrates the newly built AE system in the MIT Rock Physics Laboratory using a ball-bouncing system. Full waveforms of multibounce events due to ball drops are used to infer the transfer function of lead zirconate titanate (PZT) sensors in high pressure environments. Uncertainty in the sensor transfer functions is quantified using a waveform-based Bayesian approach. The quantification of in situ sensor transfer functions makes it possible to apply full waveform analysis for acoustic emissions at high pressures.

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Makarov, I. S. "A fast transfer function algorithm for nonuniform acoustic tubes." Acoustical Physics 57, no. 5 (September 2011): 709–21. http://dx.doi.org/10.1134/s1063771011040154.

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Gunda, Rajendra, and Sandeep Vijayakar. "Computing Radiated Sound Power using Quadratic Power Transfer Vector (QPTV)." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 2 (August 1, 2021): 4257–67. http://dx.doi.org/10.3397/in-2021-2643.

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Pressure Acoustic Transfer Functions or Vectors (PATVs) relate the surface velocity of a structure to the sound pressure level at a field point in the surrounding fluid. These functions depend only on the structure geometry, properties of the fluid medium (sound speed and characteristic density), the excitation frequency and the location of the field point, but are independent of the surface velocity values themselves. Once the pressure acoustic transfer function is computed between a structure and a specified field point, we can compute pressure at this point for any boundary velocity distribution by simply multiplying the forcing function (surface velocity) with the acoustic transfer function. These PATVs are usually computed by application of the Reciprocity Principle, and their computation is well understood. In this work, we present a novel way to compute the Velocity Acoustic Transfer Vector (VATV) which is a relation between the surface velocity of the structure and fluid particle velocity at a field point. To our knowledge, the computation of the VATV is completely new and has not been published in earlier works. By combining the PATVs and VATVs at a number of field points surrounding the structure, we obtain the Quadratic Power Transfer Vector (QPTV) that allows us to compute the sound power radiated by a structure for ANY surface velocity distribution. This allows rapid computation of the sound power for an arbitrary surface velocity distributions and is useful in designing quiet structures by minimizing the sound power radiated.

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Deng, Kai, Shenglang Zhao, Chenyang Xue, Jinlin Hu, Yi Zhong, and Yingjie Zhong. "Combustion Instability of Swirl Premixed Flame with Dielectric Barrier Discharge Plasma." Processes 9, no. 8 (August 14, 2021): 1405. http://dx.doi.org/10.3390/pr9081405.

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The effects of plasma on the combustion instability of a methane swirling premixed flame under acoustic excitation were investigated. The flame image of OH planar laser-induced fluorescence and the fluctuation of flame transfer function showed the mechanism of plasma in combustion instability. The results show that when the acoustic frequency is less than 100 Hz, the gain in flame transfer function gradually increases with the frequency; when the acoustic frequency is 100~220 Hz, the flame transfer function shows a trend of first decreasing and then increasing with acoustic frequency. When the acoustic frequency is greater than 220 Hz, the flame transfer function gradually decreases with acoustic frequency. When the voltage exceeds the critical discharge value of 5.3 kV, the premixed gas is ionized and the heat release rate increases significantly, thereby reducing the gain in flame transfer function and enhancing flame stability. Plasma causes changes in the internal recirculation zone, compression, and curling degree of the flame, and thereby accelerates the rate of chemical reaction and leads to an increase in flame heat release rate. Eventually, the concentration of OH radicals changes, and the heat release rate changes accordingly, which ultimately changes the combustion instability of the swirling flame.

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Liu, Jinlin, Huiqun Deng, Peifeng Ji, and Jun Yang. "Headphone-To-Ear Transfer Function Estimation Using Measured Acoustic Parameters." Applied Sciences 8, no. 6 (June 3, 2018): 918. http://dx.doi.org/10.3390/app8060918.

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Fokina, Margarita, Vladimir Fokin, James M. Sabatier, and Ning Xiang. "Effect of ground variability on the acoustic‐seismic transfer function." Journal of the Acoustical Society of America 114, no. 4 (October 2003): 2457. http://dx.doi.org/10.1121/1.4779609.

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PHAM THI NGOC, Y., and P. BADIN. "Vocal tract acoustic transfer function measurements : further developments and applications." Le Journal de Physique IV 04, no. C5 (May 1994): C5–549—C5–552. http://dx.doi.org/10.1051/jp4:19945118.

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Yoon, Myung-Gon, and Daesik Kim. "Acoustic transfer function of a combustion system with premixing chamber." Journal of Mechanical Science and Technology 31, no. 12 (December 2017): 6069–76. http://dx.doi.org/10.1007/s12206-017-1151-8.

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Li, Jiangqiao, Li Jiang, Fujian Yu, Ye Zhang, and Kun Gao. "Research on improving measurement accuracy of acoustic transfer function of underwater vehicle." MATEC Web of Conferences 336 (2021): 01006. http://dx.doi.org/10.1051/matecconf/202133601006.

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To address the problem that acoustic transfer functions with underwater platforms cannot be measured accurately, this paper presents a method based on phase compensation to improve the accuracy of acoustic transfer function measurements on underwater platforms. The time-domain impulse response signals with multiple cycles are first collected and intercepted, and then their phase differences are estimated using the least-squares method, and phase compensation is used to align the phases of all the signals, and then the impulse response signals are weighted and averaged over all the impulse response signals to cancel out the random noise. The water pool test proves that this method reduces the measurement random noise while obtaining a high-fidelity time domain transfer function, which effectively improves the signal-to-noise ratio of the measurement. The method adopts only one measurement signal, and without changing the measurement system, the random noise is cancelled out by the in-phase superposition of the multi-cycle impulse response signals to avoid the nonlinear distortion of the measurement results.

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Shripad, Kumar Milind Rewanand, and Sriram Sundar. "Development of experimental vibro-acoustic transfer function for a system with combined rolling-sliding motion." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 5 (August 1, 2021): 1505–15. http://dx.doi.org/10.3397/in-2021-1858.

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Combined rolling-sliding contact is present in popular non-linear systems such as cam-follower, gears, clutches, and brakes. These systems produce significant noise due to complex contact between the components during operation. The noise generated is a strong function of the contact parameters and excitation to the system. The objective of this study is to develop a transfer function to quantify the vibro-acoustic noise for various contact conditions. Acceleration, reaction forces, and acoustic pressure measurements are made on a cam-follower setup with combined rolling-sliding contact. Experiments are performed under different conditions of friction, lubrication, load, and speed. Contact forces are back-calculated using the kinematics. The transfer function relating the acoustic pressure to different forces is estimated. It is observed that the contact parameters govern the transfer function and hence the vibro-acoustic systems. The developed transfer function is useful in designing better sub-systems with combined rolling-sliding contact to reduce noise exposure, as a direct technique to relate the contact parameters to the noise does not exist. This study can be extended to other complex systems such as gears and clutches.

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Li, Song, and Jürgen Peissig. "Measurement of Head-Related Transfer Functions: A Review." Applied Sciences 10, no. 14 (July 21, 2020): 5014. http://dx.doi.org/10.3390/app10145014.

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A head-related transfer function (HRTF) describes an acoustic transfer function between a point sound source in the free-field and a defined position in the listener’s ear canal, and plays an essential role in creating immersive virtual acoustic environments (VAEs) reproduced over headphones or loudspeakers. HRTFs are highly individual, and depend on directions and distances (near-field HRTFs). However, the measurement of high-density HRTF datasets is usually time-consuming, especially for human subjects. Over the years, various novel measurement setups and methods have been proposed for the fast acquisition of individual HRTFs while maintaining high measurement accuracy. This review paper provides an overview of various HRTF measurement systems and some insights into trends in individual HRTF measurements.

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He, Hai, Hong Zhou, and Xiang Li. "Study on Test Method of Interior Noise Caused by Body Panels." Applied Mechanics and Materials 365-366 (August 2013): 650–53. http://dx.doi.org/10.4028/www.scientific.net/amm.365-366.650.

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This paper introduced four common test methods of acoustic contribution of body panels. The methods using PU sensor to array measure vibration velocity of body panels. Then, the vibration velocity of body panel multiplied by the area of panel to get the value of sound source intensity. Use reciprocity method to measure acoustic transfer function. In the experiment, the vector sum of the product of sound-source intensity and acoustic transfer function is used to compose the sound pressure contribution of the panels. The experiment proves that the composite value of acoustic pressure spectrum of drivers right ear coincide with the measured value. Therefore, this method is proved to be valid.

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20

Bellucci, Valter, Bruno Schuermans, Dariusz Nowak, Peter Flohr, and Christian Oliver Paschereit. "Thermoacoustic Modeling of a Gas Turbine Combustor Equipped With Acoustic Dampers." Journal of Turbomachinery 127, no. 2 (April 1, 2005): 372–79. http://dx.doi.org/10.1115/1.1791284.

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In this work, the TA3 thermoacoustic network is presented and used to simulate acoustic pulsations occurring in a heavy-duty ALSTOM gas turbine. In our approach, the combustion system is represented as a network of acoustic elements corresponding to hood, burners, flames and combustor. The multi-burner arrangement is modeled by describing the hood and combustor as Multiple Input Multiple Output (MIMO) acoustic elements. The MIMO transfer function (linking acoustic pressures and acoustic velocities at burner locations) is obtained by a three-dimensional modal analysis performed with a Finite Element Method. Burner and flame analytical models are fitted to transfer function measurements. In particular, the flame transfer function model is based on the time-lag concept, where the phase shift between heat release and acoustic pressure depends on the time necessary for the mixture fraction (formed at the injector location) to be convected to the flame. By using a state-space approach, the time domain solution of the acoustic field is obtained. The nonlinearity limiting the pulsation amplitude growth is provided by a fuel saturation term. Furthermore, Helmholtz dampers applied to the gas turbine combustor are acoustically modeled and included in the TA3 model. Finally, the predicted noise reduction is compared to that achieved in the engine.

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Khusnutdinova, Ilvina Gamirovna, and Musa Gumerovich Bashirov. "The Use of Electromagnetic-Acoustic Method for Estimating the Stress-Strain State of the Metallic Elements of Power Equipment." Key Engineering Materials 743 (July 2017): 463–67. http://dx.doi.org/10.4028/www.scientific.net/kem.743.463.

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As the title implies the article deals with the problem of stress-strain assessment of metallic elements in power-generating equipment. An electromagnetic-acoustical method is proposed to test and diagnose the technical condition of power apparatuses. It is stressed that the transfer function is an integral parameter that makes it possible to assess the condition of metal in a unit under test. The studies established the relationship between the quantitative values of polynomial roots of the transfer function in the system “a unit under test - electromagnetic acoustic transducer” and the level of the stress-strain state of metal.

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Gonçalves, Maria Inês Rebelo, Paulo Augusto de Lima Pontes, Vanessa Pedrosa Vieira, Antônio Augusto de Lima Pontes, Daniella Curcio, and Noemi Grigoletto De Biase. "Transfer function of Brazilian Portuguese oral vowels: a comparative acoustic analysis." Brazilian Journal of Otorhinolaryngology 75, no. 5 (October 2009): 680–84. http://dx.doi.org/10.1590/s1808-86942009000500012.

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Gonçalves, Maria Inês Rebelo, Paulo Augusto de Lima Pontes, Vanessa Pedrosa Vieira, Antônio Augusto de Lima Pontes, Daniella Curcio, and Noemi Grigoletto De Biase. "Transfer function of Brazilian Portuguese oral vowels: a comparative acoustic analysis." Brazilian Journal of Otorhinolaryngology 75, no. 5 (September 2009): 680–84. http://dx.doi.org/10.1016/s1808-8694(15)30518-8.

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KADOMATSU, Koji, and Yoshihisa IWANAGA. "Vibro-Acoustic Transfer Function and Driving-Point Conductance for Vehicle Body." Transactions of the Japan Society of Mechanical Engineers Series C 68, no. 676 (2002): 3561–65. http://dx.doi.org/10.1299/kikaic.68.3561.

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Beh, Jounghoon. "Sequential Estimation of Relative Transfer Function in Application of Acoustic Beamforming." Information 11, no. 11 (October 28, 2020): 505. http://dx.doi.org/10.3390/info11110505.

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In this paper, a sequential approach is proposed to estimate the relative transfer functions (RTF) used in developing a generalized sidelobe canceller (GSC). The latency in calibrating microphone arrays for GSC, often suffered by conventional approaches involving batch operations, is significantly reduced in the proposed sequential method. This is accomplished by an immediate generation of the RTF from initial input segments and subsequent updates of the RTF as the input stream continues. From the experimental results via the mean square error (MSE) criterion, it has been shown that the proposed method exhibits improved performance over the conventional batch approach as well as over recently introduced least mean squares approaches.

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So, C. H., and H. C. Kim. "Acoustic transfer function of a photoacoustic cell: the transmission matrix method." Journal of Physics E: Scientific Instruments 22, no. 8 (August 1989): 626–30. http://dx.doi.org/10.1088/0022-3735/22/8/019.

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27

Meier, Hilmar. "Hearing Device With Transfer Function Adjusted According To Predetermined Acoustic Environments." Journal of the Acoustical Society of America 130, no. 6 (2011): 4182. http://dx.doi.org/10.1121/1.3669366.

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Baddour, Natalie. "A multi-dimensional transfer function approach to photo-acoustic signal analysis." Journal of the Franklin Institute 345, no. 7 (October 2008): 792–818. http://dx.doi.org/10.1016/j.jfranklin.2008.04.010.

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Zhang, Jie, Jun Du, and Li-Rong Dai. "Sensor Selection for Relative Acoustic Transfer Function Steered Linearly-Constrained Beamformers." IEEE/ACM Transactions on Audio, Speech, and Language Processing 29 (2021): 1220–32. http://dx.doi.org/10.1109/taslp.2021.3064399.

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Gao, Yin Han, Zhi Bo Wang, Jie Liang, Li Tong Zhang, Ying Jie Liu, and Wen Jun Jiang. "Noise Transfer Function Refinement of Commercial Vehicle Cab Based on the Vibro-Acoustic Model." Applied Mechanics and Materials 551 (May 2014): 284–89. http://dx.doi.org/10.4028/www.scientific.net/amm.551.284.

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The TPA method has gradually developed into a mature approach to solve the internal noise problem of vehicles in recent years. Among the excitation transfer path from excitation to the noise at the target point, the noise transfer function is an important path. The noise transfer function is an inherent property of the commercial vehicle cab like the modes. When noise transfer function is low; the noise caused by the vibration transformed from the suspension is relatively low, which will be great help for the comfort of the cab. A vibro-acoustic model of some commercial vehicle cab has been built in this research, and the low frequency region noise transfer function from the mount points to the driver's ears has been simulated. From the comparison of the numerical result and the relevant test result, the accuracy of the simulation model has been proved. For the sensitive frequencies, the vibro-acoustic modes have larger vibration on some thin plates, which has been proved to be the reason for the peak for the noise transfer function. In order to reduce the noise transfer function, damping materials were applied to the sensitive thin plates, the modification effect proved to be content in the real working condition.

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31

Bellows, Benjamin D., Mohan K. Bobba, Jerry M. Seitzman, and Tim Lieuwen. "Nonlinear Flame Transfer Function Characteristics in a Swirl-Stabilized Combustor." Journal of Engineering for Gas Turbines and Power 129, no. 4 (December 22, 2006): 954–61. http://dx.doi.org/10.1115/1.2720545.

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An understanding of the amplitude dependence of the flame response to acoustic excitation is required in order to predict and/or correlate combustion instability amplitudes. This paper describes an experimental investigation of the nonlinear response of a lean, premixed flame to imposed acoustic oscillations. Detailed measurements of the amplitude dependence of the flame response were obtained at approximately 100 test points, corresponding to different flow rates and forcing frequencies. It is observed that the nonlinear flame response can exhibit a variety of behaviors, both in the shape of the response curve and the forcing amplitude at which nonlinearity is first observed. The phase between the flow oscillation and heat release is also seen to have substantial amplitude dependence. The nonlinear flame dynamics appear to be governed by different mechanisms in different frequency and flowrate regimes. These mechanisms were investigated using phase-locked, two- dimensional OH Planar laser-induced fluorescence imaging. From these images, two mechanisms, vortex rollup and unsteady flame liftoff, are identified as important in the saturation of the flame’s response to large velocity oscillations. Both mechanisms appear to reduce the flame’s area and thus its response at these high levels of driving.

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RAJARAM, RAJESH, and TIM LIEUWEN. "Acoustic radiation from turbulent premixed flames." Journal of Fluid Mechanics 637 (September 24, 2009): 357–85. http://dx.doi.org/10.1017/s0022112009990681.

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Turbulent combustion processes are inherently unsteady and, thus, a source of acoustic radiation. While prior studies have extensively characterized their total sound power, their spectral characteristics are not well understood. This work investigates these acoustic spectral features, including the flame's low- and high-frequency characteristics and the scaling of the frequency of peak acoustic emissions. The spatiotemporal characteristics of the flame's chemiluminescence emissions, used as a marker of heat release fluctuations, were measured and used to determine the heat release spectrum, spatial distribution and spatial coherence characteristics. These heat release characteristics were then used as inputs to an integral solution of the wave equation and compared to measured acoustic spectra obtained over a range of conditions and burners and at several spatial locations. The spectral characteristics of the flame's acoustic emissions are controlled by two processes: the underlying spectrum of heat release fluctuations that are ultimately the combustion noise source, and the transfer function relating these heat release and acoustic fluctuations. An important result from this work is the clarification of the relative roles of these two processes in controlling the shape of the acoustic spectrum. This transfer function is primarily controlled by the spatiotemporal coherence characteristics of the heat release fluctuations which are, in turn, strongly influenced by burner configuration/geometry and operating conditions. Low-frequency acoustic emissions are controlled by the heat release spectrum essentially independent of flame geometry. Both the heat release spectrum and heat release-acoustic transfer function are important at intermediate and high frequencies. An important feature of the investigated geometry that controls the heat release phase dynamics is the high-velocity flow relative to the flame speed and anchored character of the flame. This leads to convection of flame sheet disturbances (i.e. heat release fluctuations) along the front that dominates the high frequency and peak frequency scaling of the flame's acoustic emissions.

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Gudra, Tadeusz, and Krzysztof J. Opieliński. "Influence of acoustic impedance of multilayer acoustic systems on the transfer function of ultrasonic airborne transducers." Ultrasonics 40, no. 1-8 (May 2002): 457–63. http://dx.doi.org/10.1016/s0041-624x(02)00159-2.

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Kleynhans, G. F., and D. W. Childs. "The Acoustic Influence of Cell Depth on the Rotordynamic Characteristics of Smooth-Rotor/Honeycomb-Stator Annular Gas Seals." Journal of Engineering for Gas Turbines and Power 119, no. 4 (October 1, 1997): 949–56. http://dx.doi.org/10.1115/1.2817079.

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A two-control-volume model is employed for honeycomb-stator/smooth-rotor seals, with a conventional control-volume used for the throughflow and a “capacitance-accumulator” model for the honeycomb cells. The control volume for the honeycomb cells is shown to cause a dramatic reduction in the effective acoustic velocity of the main flow, dropping the lowest acoustic frequency into the frequency range of interest for rotordynamics. In these circumstances, the impedance functions for the seals cannot be modeled with conventional (frequency-independent) stiffness, damping, and mass coefficients. More general transform functions are required to account for the reaction forces, and the transfer functions calculated here are a lead-lag term for the direct force function and a lag term for the cross-coupled function. Experimental measurements verify the magnitude and phase trends of the proposed transfer functions. These first-order functions are simple, compared to transfer functions for magnetic bearings or foundations. For synchronous response due to imbalance, they can be approximated by running-speed-dependent stiffness and damping coefficients in conventional rotordynamics codes. Correct predictions for stability and transient response will require more general algorithms, presumably using a state-space format.

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Bashirov, M. G., N. N. Luneva, I. G. Khusnutdinova, E. M. Bashirova, N. M. Zakharov, and R. R. Gaziev. "Perfecting evaluation methods of energy equipment technical condition and resource based on electromagnetic-acoustic effect." E3S Web of Conferences 124 (2019): 05034. http://dx.doi.org/10.1051/e3sconf/201912405034.

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To assess the technical condition and resource for the safe operation of electric and electrical equipment, it is proposed to use the electromagnetic-acoustic effect and the dynamic identification method based on the analysis of the coordinates of the roots of the characteristic equation (polynomial of the denominator of the transfer function of the system “control object electromagnetic-acoustic transducer”) on the complex plane . The transfer function of the studied system “control object electromagneticacoustic transducer” is an integral quantitative parameter characterizing the state of the equipment metal.

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Shi, Z., J. Jarzynski, S. Bair, S. Hurlebaus, and L. J. Jacobs. "Characterization of acoustic emission signals from fatigue fracture." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 214, no. 9 (September 1, 2000): 1141–49. http://dx.doi.org/10.1243/0954406001523588.

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This paper discusses a comprehensive study that is developing a quantitative understanding of the acoustic emission (AE) signals that emanate from fatigue cracks. Two critical components of this study are the development of a transfer function that quantifies and removes geometric effects from a measured AE waveform and an experimental program that monitors and identifies AE signals that occur during the fatigue of cylindrical stainless steel specimens under torsion. Typical waveforms are collected during torsional fatigue and correlated with fracture mechanisms from different stages of testing. Three stages of fatigue are identified by AE waveform characterization and confirmed by microscopic replica observation. The other portion of this study demonstrates the effectiveness of using laser ultrasonic techniques to develop transfer functions to quantify and remove geometric effects from measured acoustic emission waveforms.

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Musha, Takaaki, and Tatsuo Kikuchi. "Validity of the vibro-acoustic reciprocity method for the measurement of the mechano-acoustical transfer function." Journal of the Acoustical Society of Japan (E) 19, no. 2 (1998): 151–53. http://dx.doi.org/10.1250/ast.19.151.

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Stephens, D. B., and S. C. Morris. "A method for quantifying the acoustic transfer function of a ducted rotor." Journal of Sound and Vibration 313, no. 1-2 (June 2008): 97–112. http://dx.doi.org/10.1016/j.jsv.2007.11.054.

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Kornilov, V. N., M. Manohar, and L. P. H. de Goey. "Thermo-acoustic behaviour of multiple flame burner decks: Transfer Function (de)composition." Proceedings of the Combustion Institute 32, no. 1 (2009): 1383–90. http://dx.doi.org/10.1016/j.proci.2008.05.022.

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Moir, T. J. "Az-domain transfer function solution to the non-minimum phase acoustic beamformer." International Journal of Systems Science 38, no. 7 (July 2007): 563–75. http://dx.doi.org/10.1080/00207720701431276.

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Attenborough, Keith, James M. Sabatier, Henry E. Bass, and Lee N. Bolen. "The acoustic transfer function at the surface of a layered poroelastic soil." Journal of the Acoustical Society of America 79, no. 5 (May 1986): 1353–58. http://dx.doi.org/10.1121/1.393663.

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Nocke, C. "In-situ acoustic impedance measurement using a free-field transfer function method." Applied Acoustics 59, no. 3 (March 2000): 253–64. http://dx.doi.org/10.1016/s0003-682x(99)00004-3.

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Leary, Del, Craig J. Hickey, James M. Sabatier, and David A. DiCarlo. "Examining surface sealing and crusting using the acoustic to seismic transfer function." Journal of the Acoustical Society of America 113, no. 4 (April 2003): 2313. http://dx.doi.org/10.1121/1.4780747.

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Togami, M., Y. Kawaguchi, R. Takeda, Y. Obuchi, and N. Nukaga. "Optimized Speech Dereverberation From Probabilistic Perspective for Time Varying Acoustic Transfer Function." IEEE Transactions on Audio, Speech, and Language Processing 21, no. 7 (July 2013): 1369–80. http://dx.doi.org/10.1109/tasl.2013.2250960.

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Farisco, Federica, Lukasz Panek, and Jim BW Kok. "Thermo-acoustic cross-talk between cans in a can-annular combustor." International Journal of Spray and Combustion Dynamics 9, no. 4 (July 2, 2017): 452–69. http://dx.doi.org/10.1177/1756827717716373.

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Thermo-acoustic instabilities in gas turbine engines are studied to avoid engine failure. Compared to the engines with annular combustors, the can-annular combustor design should be less vulnerable to acoustic burner-to-burner interaction, since the burners are acoustically coupled only by the turbine stator stage and the plenum. However, non-negligible cross-talk between neighboring cans has been observed in measurements in such machines. This study is focused on the analysis of the acoustic interaction between the cans. Simplified two-dimensional (2D) and three-dimensional (3D) equivalent systems representing the corresponding engine alike turbine design are investigated. Thermo-acoustic instabilities are reproduced using a forced response approach. Compressible large eddy simulation based on the open source computational fluid dynamics OpenFOAM framework is used applying accurate boundary conditions for the flow and the acoustics. A study of the reflection coefficient and of the transfer function between the cans has been performed. Comparisons between 2D and 3D equivalent configurations have been evaluated.

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Ewers, Megan, Sam Kincaid, and Marco Beltman. "Head related transfer function measurements of common PPE." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 4 (August 1, 2021): 2430–41. http://dx.doi.org/10.3397/in-2021-2134.

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Due to COVID 19, personal protective equipment (PPE) is now used in everyday life. Such PPE affects communication and perception. This paper provides an overview of the impact of PPE on Head Related Transfer Functions (HRTF's). Spatial acoustic effects of common PPE on human hearing can be documented to improve and inform field worker safety and communication. After a general description of the measurement process and required tools, we focus on a few methods which contribute significantly to the accuracy and analysis of PPE-based HRTF data. The dedicated setup allows measuring a full 360 degree map in automated fashion. It includes a special ring setup with 25 speakers, and a precise turn table that is used to adjust the angle of the device under test with respect to the ring. Binaural measurements were performed on a set of common PPE items on a Head And Torso Simulator (HATS) system, including hard hats, safety glasses, hearing protection, and various face masks. An overview of the data is presented.

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Kholkina, Natalya. "INFORMATION TRANSFER EFFECTIVENESS OF WARNING AND TELECOMMUNICATION SYSTEMS OF AUDIO-EXCHANGE UNDER NOISE CONDITIONS." Bulletin of Bryansk state technical university 2020, no. 5 (May 13, 2020): 49–55. http://dx.doi.org/10.30987/1999-8775-2020-5-49-55.

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In the paper shown there is presented an approach to the solution of the problem of the effectiveness parameter assessment in telecommunication systems of operational and command communication, systems of warning speakerphone and audio-exchange. There are considered the matters of the dependence investigation of the acoustic speech signal/noise ratio to the assurance of the required syllabic legibility for the possibility to increase the function effectiveness of telecommunication systems and information exchange operated under complex noise situation. There is shown the dependence of formant legibility upon the meaning of average geometric frequencies in each i-th band of a frequency spectrum of acoustic speech signals. The degree of the impact upon syllabic legibility of the acoustic speech signal/noise ratio is shown. In the paper it is shown that for obtaining speech information with syllabic legibility higher than 93% required for complete perception by a subscriber it is necessary to ensure the acoustic signal/noise ratio at the level no less than 20 dB. The problems in the probability density approximation of acoustic signals with the use of generalized polynomials on function basis systems are presented.

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Ramesh, Ananthapadmanabhan, and Sundar Sriram. "Variation in vibro-acoustic noise due to the defects in an automotive drum brake." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 4 (August 1, 2021): 2646–53. http://dx.doi.org/10.3397/in-2021-2192.

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Drum brakes are significant contributors to noise and vibration in automobiles causing discomfort to the passengers. The vibration and hence the resulting noise increase due to various inherent defects in the drum brake, such as asymmetry. This work aims to quantify the variation in the vibro-acoustic noise due to several common defects in the drum brake using an integrated non-linear vibration analytical model and a numerical acoustic model. The sources of vibro-acoustic noise sources such as contact and reaction forces are predicted using a four-degree-of-freedom non-linear contact mechanics based analytical model. A finite element based acoustic model of the drum brake is utilized to predict the force to the sound pressure transfer function in the drum brake. Product of the transfer functions and the forces gives the corresponding sound pressure level from which the overall sound pressure levels are estimated. The variation in the overall sound pressure levels due to different drum brake defects is evaluated by introducing defects to the analytical model. The results show that the overall sound pressure level is a strong function of the defects. It is envisioned that the current work will help in the development of effective health monitoring systems.

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Sun, Lian Wei. "Analysis of the Car Body Sound-Structure Interaction and the Contribution of Plate Based on LMS Virtual Lab." Applied Mechanics and Materials 224 (November 2012): 158–64. http://dx.doi.org/10.4028/www.scientific.net/amm.224.158.

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Based on a passenger car model for the analysis of objects, this paper analyses the acoustic sensitivity of this car body model by the application of the Acoustic model of LMS Virtual Lab software and in turn analyses the contribution of plate, the analysis process uses the installation position of the left front shock absorber for the vibration source , acquire the distributed cloud chart and the acoustic transfer function of driver both ears , according to the cloud chart distribution condition of the internal sound field in certain frequency can be seen ,according to the transfer function curve the frequency relative to the sensitivity peak value can be seen, the plate witch contribution is maximum can be found by analyzing the contribution of plate, these provide the guidance for the following structures design.

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Yao, Shu-Nung, Tim Collins, and Chaoyun Liang. "Head-Related Transfer Function Selection Using Neural Networks." Archives of Acoustics 42, no. 3 (September 26, 2017): 365–73. http://dx.doi.org/10.1515/aoa-2017-0038.

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AbstractIn binaural audio systems, for an optimal virtual acoustic space a set of head-related transfer functions (HRTFs) should be used that closely matches the listener’s ones. This study aims to select the most appropriate HRTF dataset from a large database for users without the need for extensive listening tests. Currently, there is no way to reliably reduce the number of datasets to a smaller, more manageable number without risking discarding potentially good matches. A neural network that estimates the appropriateness of HRTF datasets based on input vectors of anthropometric measurements is proposed. The shapes and sizes of listeners’ heads and pinnas were measured using digital photography; the measured anthropometric parameters form the feature vectors used by the neural network. A graphical user interface (GUI) was developed for participants to listen to music transformed using different HRTFs and to evaluate the fitness of each HRTF dataset. The listening scores recorded were the target outputs used to train the neural networks. The aim was to learn a mapping between anthropometric parameters and listener’s perception scores. Experimental validations were performed on 30 subjects. It is demonstrated that the proposed system produces a much more reliable HRTF selection than previously used methods.

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Journal articles on the topic 'Acoustic transfer function'

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