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using linear dispersion theory and particle-in-cell simulations, we explore the ion bernstein instability driven by the shell-type ion velocity distribution which is related to the excitation of fast magnetosonic waves in the terrestrial magnetosphere. we first demonstrate a novel idea to construct the shell velocity d... | fast magnetosonic waves driven by shell velocity distributions |
nearshore wave predictions with high resolution in space and time are needed for boating safety, to assess flood risk, and to support nearshore processes research. this study presents methods for improving regional nearshore predictions of swell-band wave energy (0.04-0.09 hz) by assimilating local buoy observations in... | assimilating global wave model predictions and deep-water wave observations in nearshore swell predictions |
we investigated laser-induced shock excitation of elastic surface waves at a free surface and a soft solid-liquid interface using a custom-designed photoelasticity imaging technique. epoxy-resin and pure water were selected as the solid and liquid media. the elastic surface waves were excited via a shock process induce... | rayleigh wave and super-shear evanescent wave excited by laser-induced shock at a soft solid-liquid interface observed by photoelasticity imaging technique |
the correct simulation of wave propagation with direct grid methods at fluid-solid interfaces requires a proper implementation of the boundary condition, which involves continuity of the normal component of the particle velocity and traction. the horizontal component of the particle velocities can differ (slip) and the... | waves at fluid-solid interfaces: explicit versus implicit formulation of the boundary condition |
multichannel analysis of surface wave (masw) method is an efficient tool to obtain near-surface s-wave velocity, and it has gained popularity in engineering practice. up to now, most examples of using the masw technique are focused on 2d models or data from a 1d linear receiver spread. we propose a 3d masw scheme. a fi... | numerical investigation of 3d multichannel analysis of surface wave method |
compensation of changing environmental and operational conditions (eoc) is often necessary when using guided-wave based techniques for structural health monitoring in real-world applications. many studies have demonstrated that the effect of changing eoc can mask damage to a degree that a critical defect might not be d... | reconstruction of baseline time-trace under changing environmental and operational conditions |
purposethe objective of this study is to demonstrate the feasibility of x‑ray‑induced acoustic computed tomography (xact) for early breast un‑palpable microcalcification (μca) detection in three dimensions (3d). the proposed technique provides the true 3d imaging for breast volume which overcomes the disadvantage of th... | x‑ray‑induced acoustic computed tomography for 3d breast imaging: a simulation study |
we study the time-domain acoustic wave propagation in the presence of a micro-bubble. this micro-bubble is characterized by a mass density and bulk modulus which are both very small as compared to the ones of the background vacuum. the goal is to estimate the amount of pressure that is created very near (at a distance ... | acoustic cavitation using resonating micro-bubbles. analysis in the time-domain |
laser-induced wave propagation and reflection phenomenon in a functionally graded porous medium subjected to electro- magnetic field is studied in the present research. firstly, a modified generalized thermoelastic theory named modified green lindsay (mgl) for wave propagation in a porous medium is developed. the prope... | one-dimensional electro- magneto-poro-thermoelastic wave propagation in a functionally graded medium with energy dissipation |
the intrinsic anisotropy of rock influences the paths of propagating seismic waves and indicates mineralogical texture and strains; and as such it is important that laboratory measurements of such properties be fully understood. usually, when studying anisotropy, ultrasonic wave speeds are measured in a variety of stra... | accounting for pressure-dependent ultrasonic beam skew in transversely isotropic rocks: combining modelling and measurement of anisotropic wave speeds |
the article studies the dynamics of electromagnetic wave structures in a spin ladder anti-ferromagnetic medium with a coupled generalized nonlinear schrodinger model. the direct algebraic technique is used to extract the wave solutions. the solutions are obtained in the form of dark, singular, kink and dark-singular un... | investigation of electromagnetic wave structures for a coupled model in antiferromagnetic spin-ladder medium |
the seismic topographic effect is one of the debated research topics in seismology and earthquake engineering. this debate is due to the discrepancy between the observed amplification and the amplification underestimation in numerical simulations. although the numerical simulation of ground motion, which began in the 1... | establishment of a seismic topographic effect prediction model in the lushan ms 7.0 earthquake area |
the q factor is an essential parameter describing the characteristics of medium absorption within a material during wave propagation. when a seismic wave propagates within the attenuating media, its amplitude decreases and frequency band narrows, resulting in a variation in its logarithmic spectral area. based on these... | q estimation based on the logarithmic spectral area double difference |
numerical modeling has demonstrated that automatic identification system (ais) signals can be used not only to estimate vertical total electron content (tec) to supplement current tec maps and data assimilation models but also to reconstruct two-dimensional (2-d) electron density maps of the ionosphere using computeriz... | ionospheric sounding and tomography using automatic identification system (ais) and other signals of opportunity |
the lowest region of the ionosphere, the d region, plays an important role in magnetosphere-ionosphere coupling but is challenging to directly observe. the group velocity of the extremely low frequency (elf; 3-300 hz) portion of lightning induced electromagnetic radiation can be used to diagnose the d region electron d... | ionospheric d region remote sensing using elf sferic group velocity |
laser ultrasonic scanning is attractive for damage detection due to its noncontact nature, sensitivity to local damage, and high spatial resolution. however, its practicality is limited because scanning at a high spatial resolution demands a prohibitively long scanning time. inspired by binary search and compressed sen... | accelerated noncontact laser ultrasonic scanning for damage detection using combined binary search and compressed sensing |
measurements of the horizontal and vertical components of particle motion combined with estimates of the spatial gradients of the seismic wavefield enable seismic data to be acquired and processed using single dedicated multicomponent stations (e.g. rotational sensors) and/or small receiver groups instead of large rece... | spatial wavefield gradient-based seismic wavefield separation |
this paper presents an analysis of state-of-the-art of impact detection techniques for aerospace structural components as well as a study about the combination of two promising approaches for localizing an incidental impact event on a typical metallic aerospace structural component as test article. in the aeronautical ... | about the combination of high and low frequency methods for impact detection on aerospace components |
in this paper, we study the wave propagation in a metallic parallel-plate structure with glide-symmetric elliptical holes. to perform this study, we derived a mode-matching technique based on the generalized floquet theorem for glide-symmetric structures. this mode-matching technique benefits from a lower computational... | glide-symmetric metallic structures with elliptical holes for lens compression |
we review the current state of knowledge of the europan plasma environment, its effects on radio wave propagation, and its impact on the performance and design of future radar sounders for the exploration of europa's ice crust. the europan ionosphere is produced in two independently-rotating hemispheres by photo-ioniza... | radar signal propagation through the ionosphere of europa |
advances in computational science offer a principled pipeline for predictive modeling of cardiovascular flows and aspire to provide a valuable tool for monitoring, diagnostics and surgical planning. such models can be nowadays deployed on large patient-specific topologies of systemic arterial networks and return detail... | machine learning in cardiovascular flows modeling: predicting arterial blood pressure from non-invasive 4d flow mri data using physics-informed neural networks |
inducing nonreciprocal wave propagation is a fundamental challenge across a wide range of physical systems in electromagnetics, optics, and acoustics. recent efforts to create nonreciprocal devices have departed from established magneto-optic methods and instead exploited momentum based techniques such as coherent spat... | synthetic phonons enable nonreciprocal coupling to arbitrary resonator networks |
the antiferromagnetic quantum ising chain has a quantum critical point which belongs to the universality class of the transverse ising model (tim). when a longitudinal field (h ) is switched on, the phase transition is preserved, which turns to first order for h /γ →∞ , γ being the strength of the transverse field. her... | mixed-order transition in the antiferromagnetic quantum ising chain in a field |
shear wave elastography (swe) enables the probing of the mechanical properties of soft tissues in vivo and has been demonstrated to be a promising technique for the diagnosis of diseases such as staging liver fibrosis, evaluating artery stiffening, and detecting cancers. in this study, a porohyperviscoelastic model is ... | a porohyperviscoelastic model for the shear wave elastography of the liver |
in this study, several novel solutions of strain wave equation for micro-structured solids are obtained by using the powerful modified extended direct algebraic method. in micro-structured solids, the strain wave dynamical equation is utilized to model the wave propagation in micro-structured materials. we have profita... | study of bright-dark solitons of strain wave equation in micro-structured solids and its applications |
the first results from coordinated experiments between the radio receiver instrument (rri) on the enhanced polar outflow probe (e-pop) and the super dual auroral radar network (superdarn) saskatoon high frequency (hf) radar are examined for a conjunction on 8 july 2014. e-pop, a payload on the cascade, smallsat and ion... | first results of hf radio science with e-pop rri and superdarn |
we present a high-order nodal spectral element method for the two-dimensional simulation of nonlinear water waves. the model is based on the mixed eulerian-lagrangian (mel) method. wave interaction with fixed truncated structures is handled using unstructured meshes consisting of high-order iso-parametric quadrilateral... | a mixed eulerian-lagrangian spectral element method for nonlinear wave interaction with fixed structures |
the pressure-based, current-driven impedance control technique known as "electroacoustic absorption" has offered new horizons for room modal equalization at low frequencies, steerable anomalous reflection, acoustic transmission attenuation and non-reciprocal wave propagation. nevertheless, its level of performance is s... | effect of time delay on the impedance control of a pressure-based, current-driven electroacoustic absorber |
wide applications of ultra-short pulse laser technique in micromachining and thermophysical properties' measurements make the study on ultrafast transient thermal transport necessarily essential. when the characteristic time is comparable to the phonon relaxation time, phonons propagate in ballistic-diffusive regime an... | phonon wave propagation in ballistic-diffusive regime |
new data acquisition techniques are generating data at much finer temporal and spatial resolution, compared to traditional seismic experiments. this is a challenge for data centers and users. as the amount of data potentially flowing into data centers increases by one or two orders of magnitude, data management challen... | exploring approaches for large data in seismology: user and data repository perspectives |
the paper presents an explicit damage visualization methodology in an aluminum plate through the application of wave propagation mechanics. the present work describes a series of experiments and a special signal processing technique, for speedy spatial visualization of damage in different sets of test specimens. experi... | damage detection in structural element through propagating waves using radially weighted and factored rms |
this paper deals with the optical solitons of fractional coupled boussinesq, burgers-type and mkdv equations by the hypothesis of traveling wave and g′ g2-expansion scheme. these equations are important in different fields such as propagation of long water waves, fluid dynamics, and shallow water wave propagation. in c... | a variety of fractional soliton solutions for three important coupled models arising in mathematical physics |
objective. while transcranial focused ultrasound is a very promising neuromodulation technique for its non-invasiveness and high spatial resolution, its application to the human deep brain regions such as the subthalamic nucleus (stn) is relatively new. the objective of this study is to design a simple ultrasound trans... | computational modeling of a single-element transcranial focused ultrasound transducer for subthalamic nucleus stimulation |
shear deficiency in reinforced concrete (rc) structures brings the vulnerability of brittle and abrupt failure to those structures, and thus, provides very little time for taking any precautionary actions. the present study focuses on the investigations on damage progression in shear deficient rc components using acous... | investigations on acoustic emission parameters during damage progression in shear deficient and gfrp strengthened reinforced concrete components |
this paper reports, a metasurface absorber which is u-joint loaded double split o shaped with a square split patch at the center and double negative (dng) property. the proposed absorber shows significant absorption for potential applications like radar signal absorption and satellite communication, remote sensing, rf ... | u-joint double split o (udo) shaped with split square metasurface absorber for x and ku band application |
the propagation of millimeter (mmw) and submillimeter (terahertz, thz) waves in the atmosphere is subject to absorptive and dispersive effects. the resulting attenuation and temporal group delay increase in cloudy and hazy weather. in this work, the effects of water droplets suspended in the air on the propagation of e... | propagation properties of sub-millimeter waves in foggy conditions |
determining the integrity of grounding electrodes is challenging and there is need to augment expensive and time consuming excavation based methods. in this work pulse-echo methods based on acoustic guided waves were tested on model ground rods with machined model corrosion pits. the generation and propagation of the g... | acoustic guided wave techniques for detecting corrosion damage of electrical grounding rods |
various pyro-devices are used in space structures because of their high power-to-weight ratio, high reliability, and compact size. however, when a pyro-device fires, it generates a strong, high-frequency shock wave called a pyroshock wave, which causes high-frequency-sensitive electronic equipment to malfunction. there... | visualization of pyroshock wave reduction by insulator using a laser shock based simulation method |
in modern communication systems, channel state information is of paramount importance to achieve capacity. it is then crucial to accurately estimate the channel. it is possible to perform siso-ofdm channel estimation using sparse recovery techniques. however, this approach relies on the use of a physical wave propagati... | efficient deep unfolding for siso-ofdm channel estimation |
mobile communications have been undergoing a generational change every ten years or so. however, the time difference between the so-called "g's" is also decreasing. while fifth-generation (5g) systems are becoming a commercial reality, there is already significant interest in systems beyond 5g, which we refer to as the... | 6g wireless systems: vision, requirements, challenges, insights, and opportunities |
a novel approach for density measurements at the edge of a hot plasma device is presented—microwave interferometer in the limiter shadow (mils). the diagnostic technique is based on measuring the change in phase and power of a microwave beam passing tangentially through the edge plasma, perpendicular to the background ... | a new technique for tokamak edge density measurement based on microwave interferometer |
a direct time-domain approach to simulate seismic wave propagation in three-dimensional unbounded media is proposed based on the scaled boundary finite element method (sbfem). a domain of interest is commonly partitioned into a far field and a near field. the far field is modelled by the semi-analytical sbfem satisfyin... | a time-domain approach for the simulation of three-dimensional seismic wave propagation using the scaled boundary finite element method |
a supersonic jet of mach number m = 4.5 in air is produced experimentally at the apex of a miniature 150 × 50 × 5 mm converging section with a 2 × 5 mm opening by the principle of blast wave amplification through focusing. an initial plane blast wave of m = 2.4 in the convergence section is generated by the exploding w... | supersonic jet by blast wave focusing |
seismic wavefields interact with low-velocity fault damage zones. waveforms of ballistic fault zone head waves, trapped waves, reflected waves and signatures of trapped noise can provide important information on structural and mechanical fault zone properties. here we extend the class of observable fault zone waves and... | fault zone reverberations from cross-correlations of earthquake waveforms and seismic noise |
we developed a method to locate the narrow bipolar events (nbes) based on the single-station measurement of low-frequency (lf, 40-500 khz) magnetic fields. the direction finding of a two-axis magnetic sensor provides the azimuth of nbes relative to the measurement site; the ionospheric reflection pairs in the lightning... | locating narrow bipolar events with single-station measurement of low-frequency magnetic fields |
the mechanical properties of ice in cold regions are significantly affected by the variation in temperature. the existing methods to determine ice properties commonly rely on one-off and destructive compression and strength experiments, which are unable to acquire the varying properties of ice due to temperature variat... | embedded ultrasonic inspection on the mechanical properties of cold region ice under varying temperatures |
ultrasonic wave mixing is a powerful new nondestructive evaluation technique for accessing hidden subtle imperfections in materials. first, this paper derives the resonance conditions of one-way collinear mixing with cubic nonlinearity. the results show that the mixing of two collinear longitudinal waves can generate a... | one-way collinear wave mixing in solids with cubic nonlinearity based on murnaghan's potential |
lamb waves are widely used in structural health monitoring (shm) for plate-like structures. in this paper, a new and flexible ultrasonic transducer with a high photo-acoustic conversion efficiency was proposed by using candle soot nanoparticles (csnps) and polydimethylsiloxane (pdms). experimental results demonstrate t... | a flexible laser ultrasound transducer for lamb wave-based structural health monitoring |
the stability of structures that are built over rock is affected by cracks in the rock that result from weathering, thawing and freezing processes. this study investigates a new method for determining rock crack densities using elastic wave velocities. the biot-gassmann model, which consists of several elastic moduli a... | prediction of crack density in porous-cracked rocks from elastic wave velocities |
measurement of surface plasmon and surface wave propagation is important for the operation and characterization of sensors and microscope systems. one challenge is to perform these measurements both quickly and with good spatial resolution without any modification to the sample surface. this paper addresses these issue... | defocus leakage radiation microscopy for single shot surface plasmon measurement |
this paper investigates the second-order harmonics generation associated with propagation of lamb wave in pre-stressed plates. the second-order harmonic phenomena appear in a weakly non-linear medium due to material and geometry nonlinearities. this study proposes finite element (fe) models to incorporate stress consti... | second-order harmonic generation of lamb wave in prestressed plates |
arterial stiffness is found to be an early indicator of many cardiovascular diseases. among various techniques, shear wave elastography has emerged as a promising tool for estimating local arterial stiffness through the observed dispersion of guided waves. in this paper, we develop efficient models for the computationa... | arterial waveguide model for shear wave elastography: implementation and in vitro validation |
the temperature dependences of the acoustic properties of ca3ta(ga1- x al x )3si2o14 [ctgas(x)] were experimentally studied as a function of the al substitution content x. five specimens, i.e., one each of x-, y-, and z-, and two rotated y-cut specimens, were prepared from each crystal ingot of ctgas(x) (x = 0, 0.25, 0... | temperature dependence of acoustic property of ca3ta(ga,al)3si2o14 single crystals |
inspired by the filter-bank (fb) concept that is normally used for multi-rate signal processing, an fb-enabled array technique of leaky-wave antennas (lwas) is proposed and studied for creating full-band-locked frequency-scanning radar (fsr) systems in a stitched frequency-space domain. this is mainly for addressing th... | filter-bank-enabled leaky-wave antenna array technique for full-band-locked radar system in stitched frequency-space domain |
seismic intensity prediction in a geographical area from early or initial seismic waves received by a few seismic stations is a critical component of an effective earthquake early warning (eew) system. state-of-the-art deep learning-based techniques for this task suffer from limited accuracy in the prediction and, more... | real-time seismic intensity prediction using self-supervised contrastive gnn for earthquake early warning |
<title>abstract significance: physics-based simulations of photoacoustic (pa) signals are used to validate new methods, to characterize pa setups and to generate training datasets for machine learning. however, a thoroughly validated pa simulation toolchain that can simulate realistic images is still lacking. aim... | modeling toolchain for realistic simulation of photoacoustic data acquisition |
high-resolution 3-d seismic simulation imposes severe demands for computational memory, making low-storage seismic simulation particularly important. due to its high-efficiency and low-storage, the half-precision floating-point 16-bit format (fp16) is widely used in heterogeneous computing platforms, such as sunway ser... | implementation of efficient low-storage techniques for 3-d seismic simulation using the curved grid finite-difference method |
ultrasonic guided waves (ugws) have been extensively utilized in nondestructive testing and structural health monitoring (shm) for detection and real-time monitoring of structural defects. by implementing multiple piezoelectric sensors onto a plane of the target structure to form a sensor network, damages within the se... | pitch-catch ugw-based multiple damage inference: a heterogeneous graph interpretation |
linear stability analysis of plane couette flow of a viscoelastic, upper-convected maxwell (ucm) fluid past a deformable elastic solid is carried out in the low reynolds number limit using both numerical and asymptotic techniques. the ucm fluid is characterized by its viscosity η, density ρ, and relaxation time τr, whe... | flow-induced resonant shear-wave instability between a viscoelastic fluid and an elastic solid |
considering the influence of hydrostatic pressure on geometric parameters of a lining, this paper first proposes a complete global four-terminal acoustic theoretical prediction method based on phenomenological theory for a semi-active composite coating with subwavelength piezoelectric arrays in deep-sea environment, ai... | low-frequency broadband absorption of semi-active composite anechoic coating with subwavelength piezoelectric arrays in hydrostatic environments |
amplitude modulation of a compressional electromagnetic wave in a strongly magnetized electron-positron pair plasma is considered in the quantum magnetohydrodynamic regime. the important ingredients of this study are the inclusion of the external strong magnetic field, fermi quantum degeneracy pressure, particle exchan... | modulation of a compressional electromagnetic wave in a magnetized electron-positron quantum plasma |
we analyse dominant sources identified in a catalogue of more than 156 000 localizations performed using a 26-d data set recorded by a dense array set on the san jacinto fault near anza, in california. events were localized using an array processing technique called match field processing. as for all array processing t... | characterization with dense array data of seismic sources in the shallow part of the san jacinto fault zone |
scintillation is the result of oceanic turbulence reducing the bit error rate (ber) performance of oceanic optical wireless communication (owc) systems. the scintillation, also known as intensity fluctuations, occurs due to the turbulence-induced wavefront deformations. the correction of deformations by adaptive optics... | effects of adaptive optics on bit error rate of m-ary ppm oceanic optical wireless communication systems with aperture averaging in strong turbulence |
the computation of the dispersion relations for dissipative periodic lattices having the attributes of metamaterials is an actual research topic raising the interest of researchers in the field of acoustics and wave propagation phenomena. we analyze in this contribution the impact of wave damping on the dispersion feat... | micropolar dissipative models for the analysis of 2d dispersive waves in periodic lattices |
the accurate assessment of the fatigue strength for structures made of composite materials is difficult because of the great number of possible failure forms. the structural health monitoring (shm) systems are developed and applied in engineering structures for permanent monitoring the state of the constructions. in th... | the nondestructive evaluation of the gfrp composite plate with an elliptical hole under fatigue loading conditions |
interface debonding detection approaches based on stress wave measurement for concrete-filled steel tube (cfst) members have received a great deal of attention in civil and infrastructural engineering societies. the development of efficient computing approaches to investigate the mechanisms of the interface debonding d... | numerical study on interface debonding detection mechanisms with 2d spectral element method for concrete-filled steel tube using embedded pzt sensor |
a theoretical study of dust-acoustic (da) shock waves has been carried out in an unmagnetized electron depleted dusty plasma containing inertial negatively charged dust grains and nonextensive positively charged ions. the normal mode analysis is used to examine the linear properties of da waves. the reductive perturbat... | dust-acoustic shock waves in an electron depleted nonextensive dusty plasma |
in this paper we present a krylov subspace model-order reduction technique for time- and frequency-domain electromagnetic wave fields in linear dispersive media. starting point is a self-consistent first-order form of maxwell's equations and the constitutive relation. this form is discretized on a standard staggered ye... | a lanczos model-order reduction technique to efficiently simulate electromagnetic wave propagation in dispersive media |
axial transmission techniques have been extensively studied for cortical bone quality assessment. however, the modeling of ultrasonic guided waves propagation in such a complex medium remains challenging. the aim of this paper is to develop a semi-analytical finite element method to simulate the propagation of guided w... | simulation of acoustic guided wave propagation in cortical bone using a semi-analytical finite element method |
inspection of cylindrical structures using the first longitudinal ultrasonic guided wave (ugw) mode has so far been predominantly neglected. this is due to its attenuative and dispersive behaviour, at common ugw operating frequencies (20-100 khz). however, with the current knowledge on the level of attenuation in the f... | inspection of pipelines using the first longitudinal guided wave mode |
phonons are a promising simulation platform for single particles trapped in quantum wells, interatomic molecular dynamics, and, in general, potentials. earlier implementations to simulate coherent wave propagation in one-dimensional potentials using acoustic phonons with gigahertz-terahertz frequencies were based on co... | phonon engineering with superlattices: generalized nanomechanical potentials |
in this study, the magneto-thermoelastic disturbances in a homogeneous isotropic perfectly conducting thermoelastic semi-infinite medium caused by the hydrostatic initial stress is investigated. the theory of fractional order two-temperature generalized thermoelasticity associated with one relaxation time parameter is ... | wave propagation in an initially stressed elastic half-space solids under time-fractional order two-temperature magneto-thermoelasticity |
three types of antidot lattices (adls) based on a permalloy thin film, with increasing complexity of the unit cell: simple square, bi-component square, and wave-like adls were studied experimentally using both ferromagnetic resonance and brillouin light scattering spectroscopy techniques. an additional small antidot pl... | geometrical complexity of the antidots unit cell effect on the spin wave excitations spectra |
materials suitable for magnonic crystals demand low magnetic damping and long spin-wave propagation distance. in this context co -based heusler compounds are ideal candidates for magnonic based applications. in this work, antidot arrays (with different shapes) of epitaxial co2fe0.4mn0.6si heusler-alloy thin films are p... | tunability of domain structure and magnonic spectra in antidot arrays of heusler alloy |
in this work, acoustic and computer vision techniques are combined to develop an automatic procedure for biomass estimation of tuna during transfers. a side scan sonar working at 200 khz and a stereo camera, positioned facing towards the surface to record the ventral aspect of fish, are set as acquisition equipment. mo... | automatic bluefin tuna (thunnus thynnus) biomass estimation during transfers using acoustic and computer vision techniques |
an ultrasonic, resonant, pulse-echo, and air-coupled nondestructive testing (ndt) technique is presented. it is intended for components, with regular geometries where it is possible to excite resonant modes, made of materials that have a high acoustic impedance (z) and low attenuation coefficient (α). under these condi... | air-coupled and resonant pulse-echo ultrasonic technique |
passive acoustics has been identified as an important strategy to determine underwater gas flux at natural sites, or at locations related to anthropogenic activities. the ability of an acoustic system to detect, quantify and locate a gas leak is fundamentally controlled by the signal to noise ratio (snr) of the bubble ... | passive acoustic localisation of undersea gas seeps using beamforming |
not only in fundamental wave physics but also in technical areas such as radar and communication systems, high-frequency magnonics is increasingly attracting attention. here, time-resolved scanning transmission x-ray microscopy is used to directly image high-frequency spin wave propagation in cobalt-iron waveguides at ... | direct imaging of high-frequency multimode spin wave propagation in cobalt-iron waveguides using x-ray microscopy beyond 10 ghz |
in this study, diffraction of plane sh waves by a cylindrical tunnel embedded in homogeneous, isotropic and linear elastic quarter-space is investigated. analytical solution techniques are used to solve the two dimensional wave propagation problem. when the excitation is assumed to be harmonic, the governing equation w... | a note on response of tunnels to incident sh-waves near hillsides |
an annulus is a configuration characterizing the cross section of a rotating detonation engine (rde), and the dimensionless radius is a unique geometric feature of the annulus. the present study examines the effects of the dimensionless radius of the annulus on the detonation wave propagation characteristics in an rde.... | effects of the dimensionless radius of an annulus on the detonation propagation characteristics in circular and non-circular rotating detonation engines |
we use the recently deployed scanarray network of broad-band stations covering most of norway and sweden as well as parts of finland to analyse the propagation of rayleigh waves in scandinavia. applying an array beamforming technique to teleseismic records from scanarray and permanent stations in the study region, in t... | anomalous azimuthal variations with 360° periodicity of rayleigh phase velocities observed in scandinavia |
the stability of axially functionally graded pipe conveying fluid is analyzed based on the euler-bernoulli beam theory. the governing equation for transverse vibration is transformed into an infinite system of second-order ordinary differential equations by the generalized integral transform technique, which is truncat... | stability of axially functionally graded pipe conveying fluid: generalized integral transform solution |
matched field processing (mfp) is a technique to locate the source of a recorded wavefield. it is the generalization of plane-wave beamforming, allowing for curved wave fronts. in the standard approach to mfp, simple analytical green's functions are used as synthetic wavefields that the recorded wavefields are matched ... | matched field processing accounting for complex earth structure: method and review |
this article describes the generation of elastic shear waves in a soft medium using a laser beam. our experiments show two different regimes depending on laser energy. physical modeling of the underlying phenomena reveals a thermoelastic regime caused by a local dilatation resulting from temperature increase and an abl... | generation of shear waves by laser in soft media in the ablative and thermoelastic regimes |
scenario‑based earthquake simulations at regional scales hold the promise in advancing the state‑of‑the‑art in seismic risk assessment studies. in this study, a computational workflow is presented that combines (i) a broadband green's function‑based fault‑rupture and ground motion simulation—herein carried out using th... | a computational workflow for rupture‑to‑structural‑response simulation and its application to istanbul |
waves propagating through rocks when intersected with joints gets transmitted or reflected. joints or discontinuities in a rock affect the amplitude and velocity of the transmitted and reflected waves propagating through it. the changes occurring on a transmitted wave is following the properties of the incident wave na... | influence of rock joints on longitudinal wave velocity using experimental and numerical techniques |
young sea ice composed of grease and pancake ice (gpi), as well as thin floes, considered to be the most common form of sea ice fringing antarctica, is now becoming the "new normal" also in the arctic. a study of the rheological properties of gpi is carried out by comparing the predictions of two viscous wave propagati... | sar image wave spectra to retrieve the thickness of grease-pancake sea ice using viscous wave propagation models |
unsteady shock wave propagation and generation mechanisms in aviation fuel cavitation are experimentally characterized in a planar converging-diverging nozzle geometry via high-speed digital imaging and a signal processing technique that we denote as enhanced gradient shadowgraphy. two fuels, jp-5, and jp-8, in two dif... | image-based characterization of the bubbly shock wave generation and evolution in aviation fuel cavitation |
noninvasive evaluation of the rheological behavior of soft tissues may provide an important diagnosis tool. nowadays, available commercial ultrasound systems only provide shear elasticity estimation by shear wave speed assessment under the hypothesis of a purely elastic model. however, to fully characterize the rheolog... | a diffraction correction for storage and loss moduli imaging using radiation force based elastography |
the paper discusses the dependence of shear elastic waves birefringence on applied mechanical stress and preliminary plastic deformation of a material. a technique involving precision acoustic pulse echo measurements and software processing of the received time scan of signals from a piezoelectric transducer is describ... | study of the acoustoelastic effect in an anisotropic plastically deformed material |
this paper aims to adopt the total focusing method (tfm) and wavenumber method for characterizing a delamination in ballastless slab track. twelve dry point contact (dpc) transducers located at the upper surface of the slab track compose a linear array. these transducers are employed to actuate shear waves, which are s... | numerical and experimental research on identifying a delamination in ballastless slab track |
the basic features of obliquely propagating dust-acoustic (da) solitary waves (sws) in a three-component magnetized dusty plasma (containing inertial negatively as well as positively charged dust grains, and nonextensive ions) have been theoretically investigated. the reductive perturbation technique is employed in ord... | dust-acoustic solitary waves in a magnetized opposite polarity dust-plasma medium |
this work introduces the method of circular dichroism spectroscopy in the framework of the electromagnetic/optical radiation force theory. this technique is defined here as the difference in radiation force of left-handed and right-handed circularly polarized electromagnetic waves illuminating an object exhibiting rota... | optical radiation force circular dichroism spectroscopy |
structural adhesives are commonly used as bonding agents in fibre-reinforced polymer based strengthening systems for concrete structures. the effectiveness and integrity of the bonding layer can be ascertained by monitoring the stiffness and strength development of the structural adhesive throughout the curing process.... | development of analytical and numerical models for predicting the mechanical properties of structural adhesives under curing using the pzt-based wave propagation technique |
a new 3d full-wave code, named cuwa, is developed to investigate the physics of rf wave propagation in the electron cyclotron frequency range in magnetised plasmas. the code utilises the finite difference time domain (fdtd) technique and takes advantage of massive parallel computations with graphics processing units (g... | 3d full-wave computation of rf modes in magnetised plasmas |
we studied temporal variation of the differential rotation and poleward meridional circulation during solar cycle 24 using the magnetic element feature tracking technique. we used line-of-sight magnetograms obtained using the helioseismic and magnetic imager aboard the solar dynamics observatory from may 01, 2010 to ma... | solar cycle-related variation in solar differential rotation and meridional flow in solar cycle 24 |
the boundary element method (bem) is an efficient numerical method for simulating harmonic wave propagation. it uses boundary integral formulations of the helmholtz equation at the interfaces of piecewise homogeneous domains. the discretization of its weak formulation leads to a dense system of linear equations, which ... | benchmarking preconditioned boundary integral formulations for acoustics |
terahertz (thz) communications are envisioned as a promising technology, owing to its unprecedented multi-ghz bandwidth. one fundamental challenge when moving to new spectrum is to understand the science of radio propagation and develop an accurate channel model. in this paper, a wideband channel measurement campaign b... | channel measurement and ray-tracing-statistical hybrid modeling for low-terahertz indoor communications |
recent developments in additive manufacturing have allowed for a number of innovative designs in elastic metamaterials and phononic crystals used in several applications, including vibration attenuation. complex geometric patterns that were otherwise very expensive or unpractical to produce are currently feasible. howe... | a bayesian approach for wavenumber identification of metamaterial beams possessing variability |
the present paper articulates a mathematical model for the propagation of shear wave in a layered structure comprised of slightly compressible finitely deformed layer over a foundation with pre-stressed fibre-reinforced stratum and pre-stressed dry sandy viscoelastic substrate. method of separation of variables has bee... | shear wave propagation in a slightly compressible finitely deformed layer over a foundation with pre-stressed fibre-reinforced stratum and dry sandy viscoelastic substrate |
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