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Analysis of Frequency Locking in Optically Driven MEMS Resonators
Frequency Locking Optically Driven MEMS Resonators
2015/8/27
Thin, planar, radio frequency microelectromechan-ical systems (MEMS) resonators have been shown to self-oscillate in the absence of externalforcing whenilluminated by adirect cur-rent (dc) laser of su...
Demonstration of Nonlinear Frequency Domain Methods
Demonstration Nonlinear Frequency Domain Methods
2015/7/2
This paper demonstrates the accuracy of the nonlinear frequency domain method in applications to unsteadyflow calculations. The basis of the method is a pseudospectral approach to recast a nonli...
Optimum Shape Design for Unsteady Three-Dimensional Viscous Flows Using a Nonlinear Frequency-Domain Method
Optimum Shape Design Unsteady Three-Dimensional Viscous Flows Nonlinear Frequency-Domain Method
2015/7/2
This paper presents an adjoint method for the optimum shape design of unsteady three-dimensional viscousflows.The goal is to develop a set of discrete unsteady adjoint equations and the correspo...
The computational efficiency of non-linear frequency domain methods
Non-linear Frequency Harmonic Balance Unsteady Fluid Dynamics
2015/7/2
This paper demonstrates efficient solver technologies applied to the non-linear frequency domain (NLFD) method.The basis of the NLFD method is to assume the time period of the solutions oscillat...
NON-LINEAR FREQUENCY DOMAIN BASED OPTIMUM SHAPE DESIGN FOR UNSTEADY THREE-DIMENSIONAL FLOWS
NON-LINEAR FREQUENCY DOMAIN BASED OPTIMUM SHAPE DESIGN UNSTEADY THREE-DIMENSIONAL FLOWS
2015/7/2
This paper presents an adjoint method for the optimum shape design of unsteady flows. The goal is to develop a set of discrete unsteady adjoint equations and the corresponding boundary condition...
OPTIMUM SHAPE DESIGN FOR UNSTEADY FLOWS USING TIME ACCURATE AND NON-LINEAR FREQUENCY DOMAIN METHODS
ACCURATE NON-LINEAR FREQUENCY DOMAIN METHODS
2015/7/2
This paper presents an adjoint method for the optimum shape design of unsteady flows. The goal is to develop a set of discrete unsteady adjoint equations and their corresponding boundary conditi...
An iterative approach for modal analysis of solid rocket motor incorporating frequency dependent modulus
modal analysis eigenfrequency frequency dependent modulus
2014/5/19
The modulus of viscoelastic materials varies with excitation frequency.However,during modal analysis of frequency dependent materials,a material evaluation frequency is necessary because stiffness can...
Assessment of structural damage using natural frequency changes
Damage assessment Damage detection Strain energy Modal analysis Natural frequency
2012/2/24
The present paper develops a new method for damage localization and severity estimation based on the employment of modal strain energy. This method is able to determine the damage locations and estima...
Identification of coastal emissions of methyl chloride and methyl bromide based on high-frequency measurements on Hateruma Island
methyl chloride methyl bromide source measurement beach
2017/8/9
Hourly measurements of atmospheric methyl chloride (CH3Cl) and methyl bromide (CH3Br), as well as some other halocarbons, were performed by using automated preconcentration gas chromatography/mass spe...
A study on modified Szabo’s wave equation modeling of frequency-dependent dissipation in ultrasonic medical imaging
modified Szabo’s wave equation frequency-dependent dissipation ultrasonic medical imaging
2010/10/22
The modified Szabo’s wave equation, in which the positive fractional derivative has first been used, is a new model to describe the frequency-dependent dissipative ultrasonic wave
propagation through...
Lévy stable distribution and [0,2] power law dependence of acoustic absorption on frequency in various lossy media
Lévy stable distribution [0,2] power law dependence acoustic absorption various lossy media
2010/10/22
Absorption of acoustic wave propagation in a large variety of lossy media is characterized by an empirical power law function of frequency, 0j!jy. It has long been noted that the exponent y ranges fr...
A Frequency Decomposition Time Domain Model of Broadband Frequency-Dependent Absorption
frequency decomposition bandpass Gauss filter broadband ultrasound frequency-dependent attenuation time domain
2010/10/22
This study aims to extend the time-domain model for the frequency-dependent attenuation of a single frequency excitation to a broadband excitation via a finite frequency decomposition. Our model satis...
Use of discontinuity functions to obtain the frequency equation
light beam flexural vibration discontinuity functions frequency equation
2010/3/12
An integration technique based on the use of discontinuous functions has been applied to obtain the natural frequencies of free °exural vibrations in beams. The two examples presented show the logical...
Fractional Laplacian time-space models for linear and nonlinear lossy media exhibiting arbitrary frequency dependency
Fractional Laplacian time-space models linear and nonlinear lossy media arbitrary frequency dependency
2010/10/22
Frequency-dependent attenuation typically obeys an empirical power law with an exponent ranging from 0 to 2. The standard time-domain partial differential equation models can describe merely two extre...
Modified Szaboo wave equation models for lossy media obeying frequency power law
Modified Szaboo wave equation models lossy media frequency power law
2010/10/22
Szabo’s models of acoustic attenuation @Szabo, J. Acoust. Soc. Am. 96~1!, 491–500 ~1994!# comply well with the empirical frequency power law involving noninteger and odd-integer exponent coefficients ...