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the mechanism of seismic attenuation for shear waves was studied through the separate measure of the intrinsic dissipation and scattering coefficients. a modified version of the multiple lapse time window analysis (mltwa) was applied to about 5000 local earthquakes with magnitude 1.5 ≤ ml ≤ 4.8 occurred in the period 2... | study of the regional pattern of intrinsic and scattering seismic attenuation in eastern sicily (italy) from local earthquakes |
a lumped parameter transverse vibration model of a composite plate harvester is analyzed via harmonic balance approaches. the harvester is mainly composed of a piezoelectric circular composite clamped by two steel rings and a proof mass on the plate. the lumped parameter model is a 1.5 degree-of-freedom strongly nonlin... | nonlinear vibration analysis of a circular composite plate harvester via harmonic balance |
a method for modeling realistic laser beams smoothed by kinoform phase plates is presented. the ray-based paraxial complex geometrical optics (pcgo) model with gaussian thick rays allows one to create intensity variations, or pseudospeckles, that reproduce the beam envelope, contrast, and high-intensity statistics pred... | modeling of the cross-beam energy transfer with realistic inertial-confinement-fusion beams in a large-scale hydrocode |
photoacoustic tomography (pat) is a non-ionizing imaging modality capable of acquiring high contrast and resolution images of optical absorption at depths greater than traditional optical imaging techniques. practical considerations with instrumentation and geometry limit the number of available acoustic sensors and th... | limited-view and sparse photoacoustic tomography for neuroimaging with deep learning |
structural health monitoring techniques based on vibration measurements have been receiving large attention in the last decades, including techniques for estimating bolted joint tightness and detecting loosened bolts. due to the exposure of bolted joints to external forces, the bolts may loosen and therefore affect hea... | estimating bolt tightness using transverse natural frequencies |
reinforced concrete is of vital importance in many civil and industrial structural applications. the effective bonding between steel and concrete is the core guarantee of the safe operation of the structures. corrosion or other interface debonding in steel-concrete is a typical failure mode during the long service peri... | detection of defects in reinforced concrete structures using ultrasonic nondestructive evaluation with piezoceramic transducers and the time reversal method |
this article presents an improved nonlinear ultrasonic technique for fatigue damage detection utilizing a kind of carefully designed aluminum-lead composite metamaterial. it focuses on developing a bandgap metamaterial to improve the accuracy and identifiability of the superharmonic features from fatigue cracks by elim... | metamaterial improved nonlinear ultrasonics for fatigue damage detection |
landslides in the thompson river valley, british columbia have the potential to adversely impact vital national railway infrastructure and operations, the natural environment, cultural heritage features, communities, public safety and the economy. to better manage geohazard risks in the primary national transportation ... | multi-technique geophysical investigation of a very slow-moving landslide near ashcroft, british columbia, canada |
in the developing field of magnonics, it is very important to achieve tailoring of spin wave propagation by both a proper combination of materials with different magnetic properties and their nanostructuring on the submicrometric scale. with this in mind, we have exploited deep ultraviolet lithography, in combination w... | collective spin excitations in bicomponent magnonic crystals consisting of bilayer permalloy/fe nanowires |
the net movement of lagrangian particles under water waves comprises a stokes drift in the direction of wave propagation and an eulerian return flow in the opposing direction. accurate prediction of the eulerian return flow in the ocean is of importance in modeling the transport of plastic pollution, oil, wreckage, and... | laboratory study of the wave-induced mean flow and set-down in unidirectional surface gravity wave packets on finite water depth |
a high-order accurate implicit-mesh discontinuous galerkin framework for wave propagation in single-phase and bi-phase solids is presented. the framework belongs to the embedded-boundary techniques and its novelty regards the spatial discretization, which enables boundary and interface conditions to be enforced with hi... | modeling wave propagation in elastic solids via high-order accurate implicit-mesh discontinuous galerkin methods |
the response of an equivalent 26 m-thick deposit of dry, medium-dense, nevada sand with a relative density of 60% is measured in the centrifuge under six 1-d, horizontal earthquake motions applied to the base of the centrifuge container. several 1-d site response analysis techniques are employed to simulate the experim... | evaluation of 1-d seismic site response modeling of sand using centrifuge experiments |
in this paper, we report the evidence of topologically protected edge waves (tpews) in continuum kagome lattice. according to the bulk edge correspondence principle, such edge states are inherently linked with the topological characteristics of the material band structure and can, therefore, be predicted evaluating the... | tunable in-plane topologically protected edge waves in continuum kagome lattices |
the continuous progress in gnss (global navigation satellite system) has led to considering this measurement technique as a powerful tool for the detection of the displacement response on seismic events and a source of comprehensive information on seismic wave propagation. hence, as a natural consequence of the signifi... | towards galileo + gps seismology: validation of high-rate gnss-based system for seismic events characterisation |
guided wave testing is one of non-destructive testing techniques for pipeline inspection using low-frequency ultrasonic waves. guided wave testing uses a set of equally placed piezoelectric transducers around a pipe, and the number of transducers in the array is a key factor for suppressing higher order flexural modes.... | excitation and propagation of torsional t(0,1) mode for guided wave testing of pipeline integrity |
monitoring acoustic emissions (ae) prior to imminent failure is considered a promising technique for assessing snow slope instability. gaps in elastic wave propagation characteristics in snow hinder quantitative interpretation of ae signals. our study focuses on characterizing the propagation of acoustic reference sign... | speed and attenuation of acoustic waves in snow: laboratory experiments and modeling with biot's theory |
this paper introduces damage identification approach based on guided ultrasonic waves and 3d laser doppler vibrometry. the method is based on the fact that the symmetric and antisymmetric lamb wave modes differ in amplitude of the in-plane and out-of-plane vibrations. moreover, the modes differ also in group velocities... | damage detection in composite panels based on mode-converted lamb waves sensed using 3d laser scanning vibrometer |
this paper investigates thermal damage (microcracking) in sandstone using ultrasonic methods. previous investigations have demonstrated that microcracks and lightly compressed interfaces in solids can generate strong higher harmonic signals in a propagating time-harmonic wave. distributed cracks in rock will generate s... | relation between crack density and acoustic nonlinearity in thermally damaged sandstone |
the overall importance of x-ray phase contrast (xpc) imaging has grown substantially in the last decades, in particular with the recent advent of compact lab-based xpc systems. for optimizing the experimental xpc setup, as well as benchmarking and testing new acquisition and reconstruction techniques, monte carlo (mc) ... | x-ray phase contrast simulation for grating-based interferometry using gate |
properties of nonlinear ion-acoustic travelling waves propagating in a three-dimensional multicomponent magnetoplasma system composed of positive ions, negative ions and superthermal electrons are considered. using the reductive perturbation technique (rpt), the zkharov-kuznetsov (zk) equation is derived. the bifurcati... | bifurcations of nonlinear ion-acoustic travelling waves in a multicomponent magnetoplasma with superthermal electrons |
the variable-coefficients 3d-kudryashov-sinelshchikov (vcks) equation is an important mathematical model that describes the pressure of gas bubbles in the liquid, and is considered as an impressive phenomenon with many applications in medicine, ocean dynamics and fluid mechanics. in this paper, the vcks is investigated... | similarity reductions and wave solutions for the 3d-kudryashov-sinelshchikov equation with variable-coefficients in gas bubbles for a liquid |
the nonlinear theory of amplitude modulation of electrostatic wave envelopes in a collisionless electron-positron (ep) pair plasma is studied by using a set of vlasov-poisson equations in the context of tsallis' q -nonextensive statistics. in particular, the previous linear theory of langmuir oscillations in ep plasmas... | nonlinear landau damping and modulation of electrostatic waves in a nonextensive electron-positron-pair plasma |
the occurrence of post-sunset equatorial spread-f (esf) could have detrimental effects on trans-ionospheric radio wave propagation used in modern communications systems. this problem calls for a simple but robust model that accurately predicts the occurrence of post-sunset esf. logistic regression was implemented to mo... | modeling post-sunset equatorial spread-f occurrence as a function of evening upward plasma drift using logistic regression, deduced from ionosondes in southeast asia |
explosions are traditionally discriminated from earthquakes, using the relative amplitude of compressional and shear waves at regional and teleseismic distances known as the p/s discriminant. pyle and walter (2019) showed this technique to be less robust at shorter distances, in detecting small-magnitude earthquakes an... | effect of random 3d correlated velocity perturbations on numerical modeling of ground motion from the source physics experiment |
quality factor, q, is a parameter that characterizes the energy dissipation during seismic wave propagation. the reservoir pore is one of the main factors that affect the value of q. especially, when pore space is filled with oil or gas, the rock usually exhibits a relative low q value. such a low q value has been used... | q estimation of seismic data using the generalized s-transform |
when modeling time-domain elastic wave propagation in an unbound space, the standard perfectly matched layer (pml) is straightforward for the first-order partial differential equations (pdes); by contrast, the pml requires tremendous re-constructions of the governing equations in the second-order pde form, which is how... | a simple implementation of pml for second-order elastic wave equations |
traveling ionospheric disturbances (tids) have been detected using various measurement techniques, including hf sounders, incoherent scatter radars, in situ measurements, and optical techniques. however, observations of tids have tended to be sparse and there is a need for additional observations to provide new scienti... | analysis of traveling ionospheric disturbances (tids) in gps tec launched by the 2011 tohoku earthquake |
this paper proposes a novel technique for leak detection and localization in industrial fluid pipelines. artificial intelligence-based supervised methods are a popular adoption for pipeline leak identification. however, supervised techniques need prior knowledge about pipeline failure for training purposes. to address ... | industrial fluid pipeline leak detection and localization based on a multiscale mann-whitney test and acoustic emission event tracking |
the surrogate matrix methodology delivers low-cost approximations of matrices (i.e., surrogate matrices) which are normally computed in galerkin methods via element-scale quadrature formulas. in this paper, the methodology is applied to a number of model problems in wave mechanics treated in the galerkin isogeometic se... | the surrogate matrix methodology: accelerating isogeometric analysis of waves |
interface dzyaloshinskii-moriya interactions (idmis) in interlayer exchange coupled (iec) pt/co20fe60b20 (1.12 nm)/ru/co20fe60b20 (1.12 nm) systems have been studied theoretically and experimentally. a vibrating sample magnetometer has been used to measure their magnetization at saturation and their interlayer exchange... | interface dzyaloshinskii-moriya interaction in the interlayer antiferromagnetic-exchange coupled pt/cofeb/ru/cofeb systems |
ground-penetrating radar (gpr) is an established geophysical tool to explore a wide range of near-surface environments. today, the use of synthetic gpr data is largely limited to 2d because 3d modeling is computationally more expensive. in fact, only recent developments of modeling tools and powerful hardware allow for... | 3d modeling of ground-penetrating radar data across a realistic sedimentary model |
structural adhesives are employed as bonding agents in the construction industry, to externally bond fibre-reinforced polymer (frp) composite materials onto existing structures for strengthening and repair purposes. the strength development of such structural adhesives throughout the curing process is critical to the s... | piezoelectric-based monitoring of the curing of structural adhesives: a novel experimental study |
we use porotomo experimental data to compare the performance of distributed acoustic sensing (das) and geophone observations in retrieving data to execute standard subsurface mapping and seismic monitoring activities. the porotomo experiment consists of two "seismic systems": (a) a 8.6 km long optical fibre cable deplo... | distributed acoustic sensing as a tool for subsurface mapping and seismic event monitoring: a proof of concept |
effective medium theory aims to describe a complex inhomogeneous material in terms of a few important macroscopic parameters. to characterize wave propagation through an inhomogeneous material, the most crucial parameter is the effective wavenumber. for this reason, there are many published studies on how to calculate ... | a proof that multiple waves propagate in ensemble-averaged particulate materials |
we present a systematic investigation of several discretization approaches for transient elastodynamic wave propagation problems. this comparison includes a finite difference, a finite volume, a finite element, a spectral element and the scaled boundary finite element method. numerical examples are given for simple geo... | on the numerical convergence and performance of different spatial discretization techniques for transient elastodynamic wave propagation problems |
we present a homogenization model for a single row of locally resonant inclusions. the resonances, of the mie type, result from a high contrast in the shear modulus between the inclusions and the elastic matrix. the presented homogenization model is based on a matched asymptotic expansion technique; it slightly differs... | two scale homogenization of a row of locally resonant inclusions - the case of anti-plane shear waves |
a theoretical and numerical analysis of dust-ion-acoustic (dia) shock waves has been carried out in an unmagnetized dusty multi-ion plasma containing nonextensive electrons, inertial negatively charged heavy ions, positively charged maxwellian light ions, and negatively charged stationary dusts. the normal mode analysi... | dust-ion-acoustic shock waves in nonextensive dusty multi-ion plasmas |
by comparing the seismic wave velocity profile in the earth with laboratory data of the sound velocity of iron alloys, we can infer the chemical composition of materials in the earth's core. the sound velocity of pure iron (fe) has been sufficiently measured using various techniques, while experimental study on the sou... | measurements of sound velocity in iron-nickel alloys by femtosecond laser pulses in a diamond anvil cell |
the longitudinal electric field produced by focusing a radially polarized beam is applied in confocal laser scanning microscopy by introducing a higher-order transverse mode, combined with a technique of polarization conversion for signal detection. this technique improves signal detection corresponding to the longitud... | imaging with a longitudinal electric field in confocal laser scanning microscopy to enhance spatial resolution |
based on the euler-bernoulli beam theory and kelvin-voigt model, a nonlinear model for the transverse vibration of a pipe under the combined action of base motion and pulsating internal flow is established. the governing partial differential equation is transformed into a nonlinear system of fourth-order ordinary diffe... | nonlinear dynamics of viscoelastic pipe conveying pulsating fluid subjected to base excitation |
in the age of big data availability, data-driven techniques have been proposed recently to compute the time evolution of spatio-temporal dynamics. depending on the required a priori knowledge about the underlying processes, a spectrum of black-box end-to-end learning approaches, physics-informed neural networks, and da... | up-net: a generic deep learning-based time stepper for parameterized spatio-temporal dynamics |
hydrographic surveys enable the acquisition and processing of bathymetric data, which after being plotted onto nautical charts, can help to ensure safety of navigation, monitor changes in the coastal zone, and assess hydro-engineering structure conditions. this study involves the measurement of waterbody depth, identif... | analysis of methods for determining shallow waterbody depths based on images taken by unmanned aerial vehicles |
ambient seismic noise cross-correlation with three-component sensors yields a nine-component empirical green's tensor, in which four components of the radial-vertical plane contain rayleigh waves. we exploit the retrograde elliptical nature of particle motion of the fundamental mode rayleigh wave to correct the phase o... | using multicomponent ambient seismic noise cross-correlations to identify higher mode rayleigh waves and improve dispersion measurements |
we implement the concept of complete local symmetry in lossy acoustic waveguides. despite the presence of losses, the existence of a spatially invariant current is shown theoretically and observed experimentally. we demonstrate how this invariant current leads to the generalization of the bloch and parity theorems for ... | invariant currents in lossy acoustic waveguides with complete local symmetry |
in this paper, emergence of negative axial acoustic radiation force on a rigid oscillating spherical body is investigated for acoustic manipulation purposes. the problem of plane acoustic wave scattering from an oscillating spherical body submerged in an ideal acoustic fluid medium is solved. for the case of oscillatin... | acoustic manipulation of oscillating spherical bodies: emergence of axial negative acoustic radiation force |
soft materials can be designed with a functionally graded (fg) property for specific applications. such material inhomogeneity can also be found in many soft biological tissues whose functionality is only partly understood to date. in this paper, we analyze the axisymmetric guided wave propagation in a pressurized fg e... | on propagation of axisymmetric waves in pressurized functionally graded elastomeric hollow cylinders |
the application of immersed boundary methods in static analyses is often impeded by poorly cut elements (small cut elements problem), leading to ill-conditioned linear systems of equations and stability problems. while these concerns may not be paramount in explicit dynamics, a substantial reduction in the critical tim... | an eigenvalue stabilization technique for immersed boundary finite element methods in explicit dynamics |
in this paper the elastic wave propagation phenomenon was used to detect the initiation of the fatigue damage in isotropic plate with a circular hole. the safety and reliability of structures mostly depend on the effectiveness of the monitoring methods. the structural health monitoring (shm) system based on the active ... | fatigue crack detection and identification by the elastic wave propagation method |
structural health monitoring (shm) based on guided waves allows assessing the health of a structure due to the sensitivity to the occurrence of delamination. however, wave propagation presents several complexities for effective damage identification in composite structures. an efficient implementation of a guided wave-... | damage detection tomography based on guided waves in composite structures using a distributed sensor network |
the non-collinear wave mixing technique was used for the quantitative evaluation of fatigue cracks. two shear waves intersect and interact with fatigue cracks, which lead to the generation of a longitudinal wave. non-collinear wave mixing experiments were conducted on different specimens, whereby the position at which ... | fatigue crack evaluation using the non-collinear wave mixing technique |
the weathering of rock through various mechanisms can be characterized by multiple techniques. for example, the compressional wave velocity has been mainly used with the advantage of being a non-destructive method. however, the application of shear wave velocity, which is suitable for representing the lithological char... | characterization of rock weathering using elastic waves: a laboratory-scale experimental study |
within the field of elastography, a relatively new approach analyzes the limiting case of shear waves established as a reverberant field. in this framework, it is assumed that a distribution of shear waves exists, oriented across all directions in 3d and continuous in time. the simultaneous multi-frequency application ... | an initial study of complete 2d shear wave dispersion images using a reverberant shear wave field |
in this study, we analyzed a large number of vertical sounding ionograms, obtained by the mid-latitude cyclone ionosonde (55.85° n; 48.8° e) of kazan (volga region) federal university, which operates in a rapid-run mode of ionograms (1 ionogram per minute). ionograms with a sporadic e layer type c, which have an unusua... | sporadic e layer with a structure of double cusp in the vertical sounding ionogram |
structural health monitoring aims to reduce life-cycle costs as well as design constraints of composites due to unforeseen events like impacts with objects. guided waves are effectively employed in this process because they show a great sensitivity to flaws in the structure and are able to provide a continuous monitori... | experimental characterization of a damage detection and localization system for composite structures |
in this paper, the soliton solutions and dynamical wave structures for the generalized (3+1)-dimensional shallow water wave (sww) equation, which is an important physical property in ocean engineering and hydrodynamics, are presented. the generalized exponential rational function (gerf) method is used to investigate th... | analytical soliton solutions to the generalized (3+1)-dimensional shallow water wave equation |
observations of seismic anisotropy at the base of the mantle are abundant. given recent progress in understanding how deformation relates to anisotropy in lowermost mantle minerals at the relevant pressure and temperature conditions, these observations can be used to test specific geodynamic scenarios, and have the pot... | sensitivity of sk(k)s and scs phases to heterogeneous anisotropy in the lowermost mantle from global wavefield simulations |
accurate simulation of seismic waves is of critical importance in a variety of geophysical applications. based on recent works on staggered discontinuous galerkin methods, we have developed a new method for the simulations of seismic waves, which has energy conservation and extremely low grid dispersion, so that it nat... | a staggered discontinuous galerkin method for the simulation of seismic waves with surface topography |
in active underground mining environments, monitoring of the rockmass has important implications for both safety and productivity. monitoring can be accomplished by exploiting the many passive seismic sources (microearthquakes, drilling, ore-crushers etc.) around the mine on the condition they can be accurately detecte... | interferometric methods for spatio temporal seismic monitoring in underground mines |
the arrival lamb waves of a receiver usually contain multiple wave packets corresponding to different propagation distances. it is important to accurately identify the propagation distances in lamb wave inspection and structural health monitoring for damage location. while techniques such as multiplying group velocity ... | sparse estimation of propagation distances in lamb wave inspection |
this contribution presents a novel windowed green function (wgf) method for the solution of problems of wave propagation, scattering and radiation for structures which include open (dielectric) waveguides, waveguide junctions, as well as launching and/or termination sites and other nonuniformities. based on use of a "s... | windowed green function method for nonuniform open-waveguide problems |
in this paper, we present an occupant localization approach through sensing footstep-induced floor vibrations. occupant location information is an important part of many smart building applications, such as energy and space management in a personal home or patient tracking in a hospital room. adoption of current occupa... | occupant localization using footstep-induced structural vibration |
a robust and flexible technique to segment seafloor acoustic mapping data by analyzing co-located bathymetric digital elevation models and acoustic backscatter mosaics is presented. the algorithm first uses principles of topographic openness, pattern recognition, and texture classification to identify geomorphic elemen... | a bathymetry- and reflectivity-based approach for seafloor segmentation |
visibility scintillation resulting from wave propagation through the turbulent ionosphere can be an important source of noise at low radio frequencies (ν ≲ 200 mhz). many low-frequency experiments are underway to detect the power spectrum of brightness temperature fluctuations of the neutral-hydrogen 21-cm signal from ... | scintillation noise power spectrum and its impact on high-redshift 21-cm observations |
changes in biomechanical properties of biological soft tissues are often associated with physiological dysfunctions. since biological soft tissues are hydrated, viscoelasticity is likely suitable to represent its solid-like behavior using elasticity and fluid-like behavior using viscosity. shear wave elastography is a ... | viscoelasticity imaging of biological tissues and single cells using shear wave propagation |
we study the multimode wave propagation in inhomogeneous coupled nonlinear optical fibers modeled by the variable-coefficient coupled nonlinear schrödinger (vc-cnls) equations. the effect of the optical parameters on the modulational instability criterion for the vc-cnls equations is numerically investigated. the highe... | modulational instability, nonautonomous characteristics and semirational solutions for the coupled nonlinear schrödinger equations in inhomogeneous fibers |
providing energy from fusion and finding ways to scale up the fusion process to commercial proportions in an efficient, economical, and environmentally benign way is one of the grand challenges for engineering. controlling the burning plasma in real-time is one of the critical issues that need to be addressed. plasma p... | advances, challenges, and future perspectives of microwave reflectometry for plasma position and shape control on future nuclear fusion devices |
in this paper, we consider the operator properties of various phononic eigenvalue problems. we aim to answer some fundamental questions about the eigenvalues and eigenvectors of phononic operators. these include questions about the potential real and complex nature of the eigenvalues, whether the eigenvectors form a co... | on the properties of phononic eigenvalue problems |
the process of shear interaction of an underground pipeline with soil is numerically modeled in a one-dimensional statement. the main attention is paid to the behavior of soil around the pipeline. the deformation characteristics of the pipeline are ignored. a technique for the numerical solution of a one-dimensional pr... | simulation of soil behavior under longitudinal motion of underground pipeline in one-dimensional statement |
summation-by-parts (sbp) finite difference methods have several desirable properties for second-order wave equations. they combine the computational efficiency of narrow-stencil finite difference operators with provable stability on curvilinear multiblock grids. while several techniques for boundary and interface condi... | elastic wave propagation in anisotropic solids using energy-stable finite differences with weakly enforced boundary and interface conditions |
structural health monitoring using ultrasonic guided waves relies on accurate interpretation of guided wave propagation to distinguish damage state indicators. however, traditional physics based models do not provide an accurate representation, and classic data driven techniques, such as a support vector machine, are t... | structural damage detection using deep learning of ultrasonic guided waves |
we consider the very challenging problem of efficient uncertainty quantification for acoustic wave propagation in a highly heterogeneous, possibly layered, random medium, characterized by possibly anisotropic, piecewise log-exponentially distributed gaussian random fields. a multi-level monte carlo finite volume method... | multi-level monte carlo finite volume methods for uncertainty quantification of acoustic wave propagation in random heterogeneous layered medium |
enigmatic lunar seismograms recorded during the apollo 17 mission in 1972 have so far precluded the identification of shear-wave arrivals and hence the construction of a comprehensive elastic model of the shallow lunar subsurface. here, for the first time, we extract shear-wave information from the apollo active seismi... | the shallow elastic structure of the lunar crust: new insights from seismic wavefield gradient analysis |
elastic waves have different attenuation laws when propagating in various materials, which is one of the important challenges in the application of non-destructive testing methods, such as acoustic emission (ae) technology in geotechnical engineering. the study presented in this paper investigated the influence mechani... | the influence law of concrete aggregate particle size on acoustic emission wave attenuation |
strengthening of engineering structures is an important issue, especially for elements subjected to variable loads. in the case of concrete beams or slabs, one of the most popular approaches assumes mounting an external reinforcement in the form of steel or composite elements by structural adhesives. a significant disa... | detection and imaging of debonding in adhesive joints of concrete beams strengthened with steel plates using guided waves and weighted root mean square |
we investigate the excitation of quantum plasmonic states of light in graphene using end-fire and prism coupling. in order to model the excitation process quantum mechanically, we quantize the transverse-electric and transverse-magnetic surface plasmon polariton (spp) modes in graphene. a selection of regimes are then ... | quantum plasmonic excitation in graphene and loss-insensitive propagation |
seismic interferometry is now widely used to retrieve the impulse response function of the earth between two distant seismometers. the phase information has been the focus of most passive imaging studies, as conventional seismic tomography uses traveltime measurements. the amplitude information, however, is harder to i... | retrieving impulse response function amplitudes from the ambient seismic field |
full-3d seismic waveform tomography (f3dt) is the latest seismic tomography technique that can assimilate broadband, multi-component seismic waveform observations into high-resolution 3d subsurface seismic structure models. the main drawback in the current f3dt implementation, in particular the scattering-integral impl... | reducing disk storage of full-3d seismic waveform tomography (f3dt) through lossy online compression |
we prove the nonlinear stability of the planar viscous shock up to a time-dependent shift for the three-dimensional (3d) compressible navier-stokes equations under the generic perturbations, in particular, without zero mass conditions. moreover, the time-dependent shift function keeps the shock profile shape time-asymp... | nonlinear stability of planar viscous shock wave to three-dimensional compressible navier-stokes equations |
high-frequency rayleigh-wave method plays an important role in the near-surface seismic investigation. rayleigh wave propagates along the free surface, and its propagation is seriously affected by the topographic surface. rayleigh-wave propagation is more affected by canyon topography than by hill topography. hence, it... | numerical investigation of rayleigh-wave propagation on canyon topography using finite-difference method |
the poroelastodynamic equations are used to describe the dynamic solid-fluid interaction in the reservoir. to obtain the intrinsic properties of reservoir rocks from geophysical data measured in both laboratory and field, we need an accurate solution of the wave propagation in porous media. at present, the poroelastic ... | simulation of seismic wave propagation in 2-d poroelastic media using weighted-averaging finite difference stencils in the frequency-space domain |
the propagation of magnetostatic forward volume waves excited by a constricted coplanar waveguide is studied via inductive spectroscopy techniques. a series of devices consisting of pairs of submicrometer size antennae is used to perform a discrete mapping of the spin wave amplitude in the plane of a 30-nm thin yig fil... | fresnel diffraction of spin waves |
a low cross-polarization periodic-slotted ridged substrate-integrated waveguide (rsiw) leaky wave antenna (lwa) array is presented. parametric constraints of the structure were investigated to realize a periodic leaky wave antenna (plwa) with the ability of scanning from backward endfire into the forward quadrant. an a... | periodic collinear-slotted leaky wave antenna with open stopband elimination |
in this work, a nonlocal peridynamics-smoothed particle hydrodynamics (sph) coupling formulation has been developed and implemented to simulate soil fragmentation induced by buried explosions. a peridynamics-sph coupling strategy has been developed to model the soil-explosive gas interaction by assigning the soil as pe... | a peridynamics-sph coupling approach to simulate soil fragmentation induced by shock waves |
an important step in the processing of seismic data that are recorded at the free surface is the isolation of the primary incident wavefield from the total recorded wavefield (which is contaminated with the immediate reflections off the free surface). we present a 3-d wavefield reconstruction technique, based on numeri... | fd-injection-based elastic wavefield separation for open and closed configurations |
lead zirconate titanate (pzt) sensors have become popular in structural health monitoring (shm) using the electromechanical impedance (emi) technique for damage identification. the vibrations generated during the casting process in concrete structures substantially impact the conductance signature's (real part of admit... | structural damage detection through emi and wave propagation techniques using embedded pzt smart sensing units |
hypothesis. droplet spreading governs various daily phenomena and industrial processes. insights about microdroplet spreading are limited due to experimental difficulties arising from microdroplet manipulation and substrate wettability control. for droplet sizes approaching the capillary length scale, the gravitational... | spreading dynamics of microdroplets on nanostructured surfaces |
this paper presents a comprehensive overview of current deep-learning methods for automatic object classification of underwater sonar data for shoreline surveillance, concentrating mostly on the classification of vessels from passive sonar data and the identification of objects of interest from active sonar (such as mi... | a survey of underwater acoustic data classification methods using deep learning for shoreline surveillance |
purposethree‑dimensional in‑vivo dose verification is one of the standing challenges in radiation therapy. x‑ray‑induced acoustic tomography has recently been proposed as an imaging method for use in in‑vivo dosimetry. the aim of this study was to investigate the accuracy of reconstructing three‑dimensional (3d) absolu... | simulation of x‑ray‑induced acoustic imaging for absolute dosimetry: accuracy of image reconstruction methods |
transmission matrices (tms) have become a powerful and widely used tool to describe and control wave propagation in complex media. in certain scenarios the tm is partially uncontrollable, complicating its identification and use. in standard optical wavefront shaping experiments, uncontrollable reflections or additional... | intensity-only measurement of partially uncontrollable transmission matrix: demonstration with wave-field shaping in a microwave cavity |
an exact analytical solution in closed form is obtained for a two-dimensional initial-boundary-value problem of heat wave propagation in a thick slab of an anisotropic rigid thermal conductor within the dual-phase-lag model. one-sided fourier transform technique is used to obtain a formal solution. the method requires ... | two-dimensional heat conduction in a rigid thermal conductor within the dual-phase-lag model by one-sided fourier transform |
we determine mb, the original body wave magnitude developed by gutenberg and richter over the period 1942-1956, for about 3300 mw ≥ 6 earthquakes for the period 1988-present using modern broad-band seismograms. the main objective is to extend the database of energy-related parameters by combining mb databases for recen... | reviving mb |
we compare five optical coherence elastography techniques able to estimate the shear speed of waves generated by one and two sources of excitation. the first two techniques make use of one piezoelectric actuator in order to produce a continuous shear wave propagation or a tone-burst propagation (tbp) of 400 hz over a g... | comparative study of shear wave-based elastography techniques in optical coherence tomography |
ion cyclotron heating (ich) on the prototype material plasma exposure experiment (proto-mpex) is to be accomplished using the "beach-heating" technique. beach heating has not been previously demonstrated to efficiently heat core ions at the high electron density values present in proto-mpex. this work numerically inves... | computational investigation of ion cyclotron heating on proto-mpex |
self-collimation is a phenomenon that the waves propagate through a narrow channel in phononic crystals (pncs) without diffusion. although different self-collimation pncs configurations have been proposed with heuristic methods, it is still challenging to achieve a frequency-specified self-collimation. we propose a sys... | topology optimization for realizing tailored self-collimation in phononic crystals |
the article discusses the results of experiments conducted in september 2017 to prove the applicability of positioning underwater objects during their operation at depths substantially exceeding the depth of the underwater sound channel axis. the authors present results of experimental studies and numerical analysis of... | studies of spatiotemporal structure of the acoustic field formed in deep water by a broadband pulsed signal source on the shelf of the sea of japan |
m-type hexagonal barium ferrites come in the category of magnetic material that plays a key role in electromagnetic wave propagation in various microwave devices. due to their large magnetic anisotropy and large magnetization, their operating frequency exceeds above 50 ghz. doping is a way to vary its magnetic properti... | rare earth doped m-type hexaferrites; ferromagnetic resonance and magnetization dynamics |
automatic processing of ionograms to extract ionospheric propagation characteristics and electron density profile parameters is an important enabling step toward constructing real time data-assimilative models of the ionosphere. a robust and reliable feature extraction and fitting algorithm that supports both oblique a... | a robust feature extraction and parameterized fitting algorithm for bottom-side oblique and vertical incidence ionograms |
we propose a numerical modeling technique based on a frequency-dependent attenuation relation to assess, quantify and optimize the performance of any arbitrary infrasound network to monitor explosive sources such as volcanic eruptions. simulations are further enhanced by including realistic sources and propagation effe... | assessing and optimizing the performance of infrasound networks to monitor volcanic eruptions |
the compact sized cross-shaped metamaterial design is evaluated for single negative, double negative and double positive behavior for a wide range of frequencies to investigate the gap and gapless transition from backward to forward wave propagation near 17 ghz. the metamaterial designed in this study is analyzed for n... | designing and analysis of cross-shaped crlh metamaterial for wide band negative index characteristics |
the intraseasonal variability of the eastward propagating nonmigrating diurnal tide with zonal wave number 3 (de3) during 2007 in the mesosphere, ionosphere, and thermosphere is investigated using a whole atmosphere model reanalysis and satellite observations. the atmospheric reanalysis is based on implementation of da... | short-term nonmigrating tide variability in the mesosphere, thermosphere, and ionosphere |
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