Results 231 to 240 of about 519,794 (275)
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Application of the equivalent source method to outdoor directional sound sources
The Journal of the Acoustical Society of America, 2011Many outdoor sound sources, such as aircraft and moving ground vehicles, exhibit directional sound radiation patterns that can be measured in the far field. However, this information is insufficient for specifying a source function that can be used in propagation algorithms.
Sergey N. Vecherin +2 more
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Efficient broadband method for equivalent source reflection coefficient measurements
IEEE Transactions on Instrumentation and Measurement, 2001A method is described to determine the complex equivalent reflection coefficient of RF sources using a mismatched power meter connected to a set of different phase shifting two-ports. The method is efficient, as only simple instrumentation is necessary, moreover, it is a broadband method, applicable to all types of sources and directly traceable to ...
Andras Török +4 more
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Comparison of methods for measurement of equivalent source match
2015 European Microwave Conference (EuMC), 2015Equivalent source match is a quantity of a 3-port device, which is needed for power sensor calibration. The Juroshek method, a direct 3-port method and an indirect 2-port method for measuring equivalent source match are tested with different definitions of the calibration standards being used.
Johannes Hoffmann +3 more
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A surface element formulation of the equivalent source method
The Journal of the Acoustical Society of America, 1999A time-domain formulation of the equivalent source method which uses planar surface elements is presented. The boundary condition of a closed surface can be fulfilled using monopole elements for boundary conditions specifying the normal velocity, the sound pressure, or the local impedance. By interpreting the equivalent sources as double layers of free-
U. Peter Svensson +3 more
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Aeroacoustic Scattering via the Equivalent Source Method
10th AIAA/CEAS Aeroacoustics Conference, 2004A computational method for predicting the scattering of incident engine noise by an airframe in a uniform flow field has been developed. The method is based on the equations of time harmonic, linearized acoustics and employs the equivalent source method for solving an exterior Helmholtz equation boundary value problem. Details of the governing equation
Mark Dunn, Ana Tinetti
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Inverse scattering for conductors by the equivalent source method
IEEE Transactions on Antennas and Propagation, 1996The inverse scattering for two-dimensional conductors is investigated. Assume that an incident wave is incident upon conducting cylinders of unknown shape and the scattered field is measured outside. By properly processing the scattering data, the position and shape of the conducting scatterers can then be reconstructed.
null Chai-Yu Lin, null Yean-Woei Kiang
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Journal of Vibration and Acoustics, 2018
The equivalent source method (ESM) and monopole time reversal method (MTRM) are two popular techniques for noise source localization. These two methods have some similar characteristics, such as using the pressure field measured by a microphone array as the input and using similar propagation matrices obtained from the Green's function.
Chuan-Xing Bi +3 more
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The equivalent source method (ESM) and monopole time reversal method (MTRM) are two popular techniques for noise source localization. These two methods have some similar characteristics, such as using the pressure field measured by a microphone array as the input and using similar propagation matrices obtained from the Green's function.
Chuan-Xing Bi +3 more
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An equivalent source method for acoustic problems with thermoviscous effects
The Journal of the Acoustical Society of AmericaThis paper presents an equivalent source method (ESM) for analyzing sound propagation in small-scale acoustic structures with thermoviscous effects. The formulations that describe the thermal, viscous, and acoustic modes for thermoviscous acoustic problems are introduced.
Meng-Hui Liang +4 more
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Underwater measurement of source level in waveguides using equivalent source method
The Journal of the Acoustical Society of America, 2017This paper develops a method to evaluate the source level of the underwater structure in shallow water waveguides. This method requires the measurement of the pressure on a closed surface surrounding the underwater structure and the knowledge of waveguide parameters, or the measurement of the pressure and the velocity on a closed surface surrounding ...
Tengjiao He, Shiqi Mo, Erzheng Fang
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Incorporating non-linear lumped elements in FDTD: the equivalent source method
International Journal of Numerical Modelling: Electronic Networks, Devices and Fields, 1999Summary: A new approach is presented for modelling three-dimensional lumped elements in the finite-difference time-domain (FDTD) solution of Maxwell's equations. The finite-difference equations for the lumped element's circuit behaviour are derived to produce discrete relationships between the device's terminal currents and voltages.
Mix, Jason +3 more
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