Browsing by Keywords "Acoustic waves"
Now showing items 1-15 of 15
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Acoustic microscopy with mechanical scanning—A review
(IEEE, 1979-08)Acoustic waves in liquids are known to have wavelengths comparable to that of visible light if the frequency is in the gigahertz range. The phenomena of Brillouin scattering in liquids is based on such waves. In helium ... -
Classification of closed-and open-shell pistachio nuts using voice-recognition technology
(American Society of Agricultural and Biological Engineers, 2004)An algorithm using speech recognition technology was developed to distinguish pistachio nuts with closed shells from those with open shells. It was observed that upon impact with a steel plate, nuts with closed shells emit ... -
Counterflow in Bose gas bilayers: collective modes and dissipationless drag
(American Institute of Physics, 2020)We investigate the collective density oscillations and dissipationless drag effect in bilayer structures of ultra-cold bosons in the presence of counterflow. We consider different types of inter-particle interactions and ... -
Detection of empty hazelnuts from fully developed nuts by impact acoustics
(IEEE, 2005)Shell-kernel weight ratio is the main determinate of quality and price of hazelnuts. Empty hazelnuts and nuts containing undeveloped kernels may also contain mycotoxin producing molds, which can cause cancer. A prototype ... -
Imaging flaws close to surface using focused surface acoustic waves
(IEEE, 1986-11)The resolving power and detection ability of the focused surface acoustic wave (SAW) imaging modality is investigated in this paper. In this mode of imaging, conical bulk acoustic waves are used to generate and focus leaky ... -
Increasing the sensitivity of the scanning acoustic microscope to anisotropy
(IEEE, 1987)The response of the scanning acoustic microscope to anisotropic materials is theoretically investigated. For this purpose, the reflection coefficient of plane acoustic waves incident on a liquid-anisotropic-solid interface ... -
Recognition of vessel acoustic signatures using non-linear teager energy based features
(IEEE, 2016-10)This paper proposes a vessel recognition and classification system based on vessel acoustic signatures. Teager Energy Operator (TEO) based Mel Frequency Cepstral Coefficients (MFCC) are used for the first time in Underwater ... -
Reflection of ultrasonic waves at a liquid–cubic–solid interface
(A I P Publishing, 1983-02)The results of numerical calculations are presented for the reflection coefficient of sound waves incident on a liquid–cubic–solid interface. The reflection coefficient is calculated numerically for the (001) face of various ... -
Response of surface acoustic wave imaging systems to cylindrical inhomogeneities
(IEEE, 1988-10)The authors present a theory to predict the response of a SAW (surface acoustic wave) imaging system. In particular, they calculate the response to cylindrical cavities as a function of cavity position with respect to the ... -
Scattering and absorption performance of a microsize graphene-based parabolic reflector in the THz range illuminated by a complex line source
(IEEE, 2017)The scattering and absorption characteristics of a two- dimensional (2-D) parabolic reflector made of graphene and placed in the free space is simulated using the Method of Analytical Regularization (MAR) technique. Reflector ... -
A signal representation approach for discrimination between full and empty hazelnuts
(IEEE, 2007)We apply a sparse signal representation approach to impact acoustic signals to discriminate between empty and full hazelnuts. The impact acoustic signals are recorded by dropping the hazelnut shells on a metal plate. The ... -
Sound absorption coefficient changes of acoustical plates made of expanded perlite in moist environment
(WITPress, 2003)Expanded perlite is a porous, lightweight, fire resistant and moisture retaining material with sound and thermal insulation properties. In this research, acoustical behaviour of plates made of expanded perlite was studied ... -
Use of a conical axicon as a surface acoustic wave focusing device
(IEEE, 1987-01)Ultrasonic axicons generate waves which focus on a line. They are used in various imaging applications as hulk wave focusing devices with a very long depth of focus. A new type of conical axicon is introduced. It consists ... -
V(Z) of the surface acoustic wave focusing system
(IEEE, 1986-11)It is possible to define a V(Z) function for the surface acoustic wave (SAW) focusing system for a class of reflectors similar to that defined in acoustic microscopy. In this case V(Z) is a function which relates the ... -
Wave propagation and acoustic band gaps of two-dimensional liquid crystal/solid phononic crystals
(Springer Verlag, 2017)The vast majority of acoustic wave propagation in phononic band studies has been usually carried out by scattering inclusions embedded in a viscoelastic medium, such as air or water. In this study, we present calculated ...
