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Showing 1 to 16 of 16 for “"dispersion curve"”.
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Dispersion Curve Estimation for Longitudinal Rail Stress Measurement
… by extracting the spectrum relation, or dispersion curve, of a waveguide from dispersive wave propagation meaasurements. The technique is based on spectral analysis of waves in structures modeled as beams, and as such is based on relatively low frequency vibrations, as opposed to other …
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Experimental investigation of near-field effects on the SASW dispersion curve
… procedure that is used to analyze the field dispersion curve to determine the field V[subscript s] profile, the analysis is based on the wave field consisting of plane Rayleigh waves. Therefore, field dispersion curves that contain near-field data could adversely distort the field V[subscript …
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Correlation of the distribution curve with the dispersion curve of cellulose nitrate
The dielectric-dispersion, curve of cellulose nitrate may be obtained over a 1ow frequency range in h-butyl acetate. The parallel resistance method is used for capacitance measurements is a nickel cell. Comparison of the distribution curve and the dispersion curve above a distinct similarity …
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Dielectric dispersion in dilute cellulose acetate solutions
… that some polymer solutions exhibit dielectric dispersion (variation of the dielectric constant with frequency) which is apparently related in some way to the molecular weight of the polymer (1) (2) (3). One of these investigations (1) was carried out on solutions to cellulose acetate in …
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Time domain chromatic dispersion measurements in single mode optical fibers
A time domain chromatic dispersion measurement system for single-mode optical fibers is presented for easy measurements in both the laboratory and the field. This technique uses a relative group delay of a band of light at slightly different wavelengths from a single pulsed laser diode to determine …
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Body and surface wave ambient noise seismic interferometry across the Salton Sea Geothermal Field, California
… required for mode separation. The virtual source dispersion curve compared well to a dispersion curve from a nearby explosive shot. P-waves were observed on the virtual source gathers. Creation of a low-quality multichannel reflection stack revealed two weak reflectors in the upper 2 km.
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Two-photon absorption and nonlinear polariton effects in organic crystals
… of polariton fusion. The calculated polariton dispersion curve accounts for the shifts in energy of the upper component in TPE and SHG. The requirement of phase matching on the a*b face leads to creation of a polariton on the upper polariton branch, above the one-photon absorption frequency, …
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An investigation of the influence of grain size on stress wave attenuation and dispersion in rock like materials
… theory is developed to describe attenuation and dispersion in a medium. The assumption is made that the ll medium behaves in a linear manner. The influence of grain size on attenuation and dispersion is investigated and the effect of aggregate to matrix ratio also is considered. Theoretical …
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Many-body effects in the thermodynamic properites of Fermi liquids and the electron-phonon system and in the excitation spectrum of liquid 4HE
… the parameters in the theory. I calculate the dispersion curve in the absence of dynamic mode-mode coupling and discuss the results.
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Multistation Methods for Geotechnical Characterization using Surface Waves
… method for simultaneous measurements of Rayleigh dispersion and attenuation curves is proposed. Regarding the first topic, the necessity of a multistation approach to determine the experimental dispersion test is essentially related to the spatial variation of phase velocity. Analyses in the …
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Surface Wave Analysis in Laterally Varying Media
… The surface wave method exploits the geometric dispersion proper of surface waves: in a non-homogeneous medium every frequency is characterized by a different phase velocity, as every frequency component travels through a portion of medium whose thickness is proportional to its wavelength. The …
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Metal-insulator-insulator-metal plasmonic waveguides and devices
… into antenna and reactive mode regions. Spatial dispersion effect on the SH mode yields a reduced wave vector in its dispersion curve and an increased propagation loss. The MIM radiative SPPs are probed using attenuated total reflection in the Kretschmann configuration and using free space …
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Advanced analysis of complex seismic waveforms to characterize the subsurface Earth structure
… structure in urban areas, and (3) Surface wave dispersion inversion for shear wave velocity structure. Although these three projects apply different techniques and investigate different parts of the Earth, their aims are the same, which is to better understand and characterize the subsurface …
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Optimized grating coupler designs for integrated photonics
… in terms of bandwidth and asymmetry of the CE curve, is conducted and reported for such optimized non-uniform grating couplers. Here, the bandwidth is shown to be inversely proportional to the dimension of the impinging mode field diameter, which affects, together with the energy dispersion …
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Analysis of pattern dynamics for a nonlinear model of the human cortex via bifurcation theories
… can normally be inferred from the eigenvalue dispersion curve, i.e., linear stability analysis. Sometimes we experienced mismatches between the linear stability analysis and the formed cortical patterns, which hampers us in identifying the type of instability corresponding to the emergent …
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New Constraints on Fault-Zone Structure from Seismic Guided Waves
The structure of fault zones (FZs) plays an important role in understanding fault mechanics, earthquake rupture and seismic hazards. Fault zone seismic guided waves (GW) carry important information about internal structure of the low-velocity fault damage zone. Numerical modeling of observed FZGWs …