Results 291 to 300 of about 368,669 (336)

Demonstration of effective acoustic properties of different configurations of Helmholtz resonators

, 2019
Acoustic metamaterial attains uncommon material properties over natural material such as negative effective mass density or negative effective bulk modulus or both.
D. Jena, J. Dandsena, V. G. Jayakumari
semanticscholar   +1 more source

Helmholtz–Gauss waves

Journal of the Optical Society of America A, 2005
A detailed study of the propagation of an arbitrary nondiffracting beam whose disturbance in the plane z = 0 is modulated by a Gaussian envelope is presented. We call such a field a Helmholtz-Gauss (HzG) beam. A simple closed-form expression for the paraxial propagation of the HzG beams is written as the product of three factors: a complex amplitude ...
Julio C, Gutiérrez-Vega, Miguel A, Bandres   +1 more
openaire   +2 more sources

Some analytical and numerical investigation of a family of fractional‐order Helmholtz equations in two space dimensions

Mathematical methods in the applied sciences, 2019
In this article, we aim at solving a family of two‐dimensional fractional‐order Helmholtz equations by using the Laplace‐Adomian Decomposition Method (LADM).
H. Srivastava, Rasool Shah, Hassan Khan, M. Arif   +3 more
semanticscholar   +1 more source

Kernel Ridge Regression with Constraint of Helmholtz Equation for Sound Field Interpolation

International Workshop on Acoustic Signal Enhancement, 2018
Kernel ridge regression with the constraint of the Helmholtz equation for three-dimensional sound field interpolation is proposed. Interpolation of a sound field is formulated as an optimization problem whose objective function to be minimized is a ...
Natsuki Ueno, Shoichi Koyama, H. Saruwatari   +2 more
semanticscholar   +1 more source

Nonlocal inflected nano-beams: A stress-driven approach of bi-Helmholtz type

Composite structures, 2018
Size-dependent bending behavior of Bernoulli-Euler nano-beams is investigated by elasticity integral theory. Eringen’s strain-driven nonlocal integral formulation, providing the bending moment interaction field as output of the convolution between ...
R. Barretta, S. A. Fazelzadeh, L. Feo, E. Ghavanloo, R. Luciano   +4 more
semanticscholar   +1 more source

Sound absorption by a Helmholtz resonator

Acoustical Physics, 2017
A I Komkin, M A Mironov
exaly   +2 more sources

Acoustic metamaterial plate embedded with Helmholtz resonators for extraordinary sound transmission loss

Journal of Applied Physics, 2018
A new acoustic metamaterial plate (AMP) is proposed herein. The plate incorporates Helmholtz resonators that are periodically embedded at intervals shorter than acoustic wavelengths. This metamaterial plate exhibits extraordinary sound transmission loss (
Takashi Yamamoto
semanticscholar   +1 more source

How Large a Shift is Needed in the Shifted Helmholtz Preconditioner for its Effective Inversion by Multigrid?

SIAM Journal of Scientific Computing, 2017
Pierre-Henri Cocquet, Martin J Gander
exaly   +2 more sources

Helmholtz and the Psychophysiology of Time

Science in Context, 2001
ArgumentAfter having measured the velocity of the nervous impulse in the 1850s, Helmholtz began doing research on the temporal dimensions of visual perception. Experiments dealing with the velocity of propagation in nerves (as well as with aspects of perception) were carried out occasionally for some fifteen years until their final publication in 1871.
openaire   +2 more sources

On Kelvin–Helmholtz instability

The Physics of Fluids, 1980
It is shown that the wave energy for both modes in an inviscid Kelvin–Helmholtz model is positive in a reference frame moving with the density-weighted mean of the upper and lower flow speeds. This fact is significant in connection with the role of negative energy waves in hydrodynamic stability.
openaire   +2 more sources