Browsing Research Articles, Department of Biomedical Engineering and Mechanics by Issue Date
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Nonlinear acoustic propagation in twodimensional ducts
(Acoustical Society of America, 1974)The method of multiple scales is used to obtain a secondorder uniformly valid expansion for the nonlinear acoustic wave propagation in a twodimensional duct whose walls are treated with a nonlinear acoustic material. The ... 
Parallel_plate waveguide with sinusoidally perturbed boundaries
(American Institute of Physics, 1974)The method of multiple scales is used to obtain a uniformly valid asymptotic expansion for the propagation of TM modes on a parallel_plate waveguide with perfectly conducting boundary surfaces that are sinusoidally perturbed ... 
Algebraically growing waves in ducts with sheared mean flow
(Acoustical Society of America, 1974)Standing or traveling waves which vary algebraically with the axial distance in uniform ducts with sheared mean velocity profiles are investigated. The results show that such waves are not possible for ducts with uniform ... 
Nonlinear analysis of the forced response of structural elements
(Acoustical Society of America, 1974)A general procedure is presented for the nonlinear analysis of the forced response of structural elements to harmonic excitations. Internal resonances (i.e., modal interactions) are taken into account. All excitations are ... 
Sound waves in twodimensional ducts with sinusoidal walls
(Acoustical Society of America, 1974)The method of multiple scales is used to analyze the wave propagation in twodimensional hardwalled ducts with sinusoidal walls. For traveling waves,resonance occurs whenever the wall wavenumber is equal to the difference ... 
Asymptotic Solutions Of SecondOrder Linear Equations with 3 Transition Points
(AIP Publishing, 19741201)A uniformly valid asymptotic expansion is obtained for the regular solution of a class of second_order linear differential equations with three transition points_a turning point and two regular singular points. The solution ... 
Nonparallel Stability of BoundaryLayer Flows
(AIP Publishing, 1975)The spatial stability of two‐dimensional incompressible boundary‐layer flows is analyzed using the method of multiple scales. The analysis takes into account the streamwise variations of the mean flow, the disturbance ... 
Nonlinear propagation of a wave packet in a hardwalled circular duct
(Acoustical Society of America, 1975)The method of multiple scales is used to derive a nonlinear Schridinger equation for the temporal and spatial modulation of the amplitudes and the phases of waves propagating in a hardwalled circular duct. This equation ... 
Simulation of multicorrelated random processes using the FFT algorithm
(Acoustical Society of America, 1975)A technique for the digital simulation of multicorrelated Gaussian random processes is described. This technique is based upon generating discrete frequency functions which correspond to the Fourier transform of the desired ... 
Acoustic waves in ducts with sinusoidally perturbed walls and mean flow
(Acoustical Society of America, 1975)An analysis is presented of the propagation of acoustic waves in a hardwalled duct with sinusoidally perturbed walls and carrying mean flow. The results show that resonance occurs whenever the wavenumber of the wall ... 
Population difference of two_level atomic system due to a running pulsed field
(American Institute of Physics, 1975)The method of multiple scales is used to derive an expression for the population difference in an absorbing atomic system due to a running pulsed field. The main contribution to this expression comes from a quasi_steady_state ... 
Numericalperturbation technique for the transverse vibrations of highly prestressed plates
(Acoustical Society of America, 1975)Under the usual assumptions of small strains with moderately large rotations, the problem of the transverse vibrations of highly prestressed nonuniform annular plates is reduced to the solution of the differential equation ... 
Nonlinear resonances in a class of multidegreeoffreedom systems
(Acoustical Society of America, 1975)An analysis is presented of the superharmonic, subharmonic, and combination resonances in a multidegreeoffreedom system which has cubic nonlinearity and modal viscous damping and is subject to harmonic excitation. It ... 
Finiteamplitude plane waves in ducts with varying properties
(Acoustical Society of America, 1975)The method of multiple scales is used to determine a firstorder uniform expansion for finiteamplitude plane waves of continuous waveforms propagating in a duct having a slowly varying cross section and filled with an ... 
Compressible Boundary Layers Over Wavy Walls
(AIP Publishing, 1976)An analysis is presented of compressible viscous flows past wavy walls without restricting the mean flow to be linear in the disturbance layer. Linearization of the compressible disturbance equations results in a system ... 
Influence of anisotropic liners on the attenuation of sound in circular ducts
(Acoustical Society of America, 1976)An analysis is presented of the sound propagation and attenuation in a circular duct carrying a uniform mean flow and lined with an anisotropicporous material backed by cellular cavities. A combination of a fourthorder ... 
Optical resonance of a two_level atomic system
(American Institute of Physics, 1976)The method of multiple scales is used to derive a solution of the damped optical Bloch equations of a two_level atomic system due to a strong pulsed field. The time dependence of the oscillations of the atomic inversion ... 
Nonlinear modulation of TM waves in a circular waveguide
(American Institute of Physics, 1976)The method of multiple scales is used to derive a nonlinear Schrödinger equation for the temporal and spatial amplitude and phase modulations of TM waves in a perfectly conducting guide containing a nonlinear isotropic ... 
Critical angle for reflection at a liquidsolid interface in single crystals
(Acoustical Society of America, 1976)Recent investigations have utilized the measurement of the critical angle for reflection from a liquidsolid interface for determination of the elastic constants of the solid. For anisotropic media, this technique is ... 
Closed 1stOrder And 2ndOrder Moment Equations For Stochastic Nonlinear Problems with Applications To Model Hydrodynamic And VlasovPlasma Turbulence
(AIP Publishing, 19760901)Working along the lines of a procedure outlined by Keller, a technique is developed for deriving closed first_ and second_order moment equations for a general class of stochastic nonlinear equations by performing a ...