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maxwell's equations (mes) are the starting point for all calculations involving surface or borehole electromagnetic (em) methods in petroleum industry. in well-log analysis numerical modeling of resistivity and induction tool responses has became an indispensable step of interpretation. we developed a new method to num... | computer simulation of microwave propagation in heterogeneous and fractal media |
the problem of vibrations of an ice sheet with a rectilinear crack on the surface of an ideal incompressible fluid of finite depth under the action of a time-periodic local load is solved analytically using the wiener-hopf technique. ice cover is simulated by two thin elastic semi-infinite plates of constant thickness.... | action of a local time-periodic load on an ice sheet with a crack |
blasting is necessary for many operations in underground and open pit mines. explosives are employed not only in mining operations, but also in civil construction works. blasting is applied where mechanical means such as bulldozers or hydraulic excavators are unable to break up and excavate the rock mass. | a methodology based on geomechanical and geophysical techniques to avoid ornamental stone damage caused by blast-induced ground vibrations |
quantitative mechanical properties of biological tissues can be mapped using the shear wave elastography technique. this technology has demonstrated a great potential in various organs but shows a limit due to wave attenuation in biological tissues. an option to overcome the inherent loss in shear wave magnitude along ... | lorentz force induced shear waves for magnetic resonance elastography applications |
four-spacecraft missions are probing the earth's magnetospheric environment with high potential for revealing spatial and temporal scales of a variety of in situ phenomena. the techniques allowed by these four spacecraft include the calculation of vorticity and the magnetic curvature analysis (mca), both of which have ... | four-spacecraft magnetic curvature and vorticity analyses on kelvin-helmholtz waves in mhd simulations |
between 2008 and 2014, the institut de physique du globe de paris (ipgp) and the university of the west indies, seismic research centre (uwi-src) designed and built a regional seismic network across the lesser antilles. one of the goals of the network is to provide real-time seismic data to the tsunami warning centers ... | building a natural-hazard-resilient high-quality seismic network: how wi network sustained hurricanes maria and irma |
the implementation into the gins cnes geodetic software of a more efficient filter was needed to satisfy the users who wanted to compute high-rate gnss ppp solutions. we selected the sri approach and a qr factorization technique including an innovative algorithm which optimizes the matrix reduction step. a full descrip... | efficient qr sequential least square algorithm for high frequency gnss precise point positioning seismic application |
a most persistent limitation of the geometrical-optics (go) approximation is the difficulty in integrating the focusing/defocusing term in the equation for the wave amplitude when rays go through singularities (i.e., caustics and cutoffs), points where go fails and wavelengths and other wave field-related quantities (e... | an improved asymptotic matching technique to trace the wave amplitude of rays across singularities: application to lower-hybrid wave propagation in tokamaks |
the exact problem of electromagnetic wave propagation in a multilayer nanostructure with complex values of dielectric permittivity is solved. the contribution to the refractive index of an additive to the dielectric constant connected with the injected carriers is taken into account. within the framework of this proble... | simulation of temperature dependences of emission characteristics of nano-layer injection lasers based on symmetric heterostructures |
in this paper, an extensive multiple-input multiple-output measurement campaign in a lab environment has been conducted at the 94 ghz band. using a vector network analyzer, updown converters, and omnidirectional antennas displaced in virtual arrays, we have obtained an estimation of the distribution parameters for the ... | small-scale distributions in an indoor environment at 94 ghz |
due to the merits of high inspection speed and long detecting distance, ultrasonic guided wave(ugw) method has been commonly applied to the on-line maintenance of power transmission line. however, the guided wave propagation in this structure is very complicated, leading to the unfavorable defect localization accuracy.... | high precision ultrasonic guided wave technique for inspection of power transmission line |
this work presents the study on the electromagnetic wave penetration and propagation into the ionosphere in the frequency range of 100 hz to 3 khz and 3 khz to 10 khz, corresponding to the ultra low frequency (ulf) and very low frequency (vlf), respectively, for various types of applications including earthquake predic... | study of ulf-vlf wave propagation in the near-earth environment for earthquake prediction |
an angular clustering method based on image processing is proposed in this paper. it is used to identify clusters in 2d representations of propagation channels. the approach uses operations such as watershed segmentation and is particularly well suited for clustering directional channels obtained by beam-steering at mi... | angular clustering of millimeter-wave propagation channels with watershed transformation |
the 4×4 matrix method proposed by yeh is a robust technique to solve the wave propagation problem in anisotropic media. however, it fails in the isotropic limit. although the singularity of this method has been widely noted, a comprehensive discussion on the reason behind such a failure has not been reported previously... | on the singularity of the yeh 4 × 4 transfer matrix formalism |
we have developed a von neumann stability and dispersion analysis of two time-integration techniques in the framework of fourier pseudospectral (ps) discretizations of the second-order wave equation. the first technique is a rapid expansion method (rem) that uses chebyshev matrix polynomials to approximate the continuo... | comparison of expansion-based explicit time-integration schemes for acoustic wave propagation |
on-body communication technology development requires a better knowledge of antenna radiation and wave propagation along the body, in both near and far fields. therefore, green's functions associated with penetrable cylinders are briefly reviewed, considering frequencies at which the body is not much larger than the wa... | body area networks at radio frequencies: creeping waves and antenna analysis |
the prediction of vibrations in an unbounded medium and their interaction with structures on the ground surface or within the soil requires adequate approaches. therefore the numerical methods addressing the dynamic soil structure interaction (ssi) have to account for both, the infinite extent of the soil by satisfying... | a coupled integral transform method - finite element method approach to model the soil structure interaction of finite (3d) and length invariant (2.5d) systems |
characterizing cracks within elastic media forms an important aspect of ultrasonic non-destructive evaluation (nde) where techniques such as time-of-flight diffraction and pulse-echo are often used with the presumption of scattering from smooth, straight cracks. however, cracks are rarely straight, or smooth, and recen... | elastic shear wave scattering by randomly rough surfaces |
the demand for the development of non-destructive techniques aiming to assess the reliability of adhesively bonded structures has greatly increased these recent years. the multilayered plates investigated can suffer from different defects, such as delaminations, inclusions and microcracks at interfacial areas. the aim ... | modeling and numerical study of the influence of imperfect interface properties on the reflectance function for anisotropic multilayered structures |
the geometry and stiffness of a vessel are pertinent to blood dynamics and vessel wall mechanical behavior and may alter in diseased conditions. ultrasound-based ultrafast doppler (udoppler) imaging and shear wave imaging (swi) techniques have been extensively exploited for the assessment of vascular hemodynamics and m... | walled vessel-mimicking phantom for ultrasound imaging using 3d printing with a water-soluble filament: design principle, fluid-structure interaction (fsi) simulation, and experimental validation |
contactless ultrasound power transfer (upt) has emerged as one of the promising techniques for wireless power transfer. physical processes supporting upt include the vibrations at a transmitting/acoustic source element, acoustic wave propagation, piezoelectric transduction of elastic vibrations at a receiving element, ... | acoustic-electroelastic modeling of piezoelectric disks in high-intensity focused ultrasound power transfer systems |
the nonlinear propagation of ion-acoustic (ia) waves in a strongly coupled plasma system containing maxwellian electrons and nonthermal ions has been theoretically and numerically investigated. the well-known reductive perturbation technique is used to derive both the burgers and korteweg-de vries (kdv) equations. thei... | nonlinear ion modes in a strongly coupled plasma in the presence of nonthermal ion fluids and polarization force |
acoustic source localization (asl) technique is an important step for structural health monitoring (shm). asl in three dimensional (3d) structures is more challenging. the 3d acoustic source localization technology not only has important significance for the non-destructive monitoring of large-scale 3d structures, but ... | acoustic wave propagation and source localization in a 3d heterogeneous structure: a numerical study |
measuring the electrical permittivity of civil engineering materials is important for a range of ground penetrating radar (gpr) and pavement moisture measurement applications. compacted unbound granular (ubg) pavement materials present a number of preparation and measurement challenges using conventional characterisati... | optimising a modified free-space permittivity characterisation method for civil engineering applications |
guided ultrasonic wave-based methods are promising for structural health monitoring of isotropic and composite materials and structures. the technology has seen a lot of attention in the research community over the past decades, and many analytical and numerical methods have been developed to describe different aspects... | uncertainty characterization of guided ultrasonic wave properties in composite materials |
carbon fiber reinforced polymer (cfrp) composites have been widely used in aerospace structures due to their high specific strength and stiffness, resistance to corrosion, and lightweight. however, it has posed new challenges for implementing guided wave-based structural health monitoring (shm) techniques due to the ge... | damage detection in laminated composites using pure sh guided wave excited by angle beam transducer |
local interaction simulation approach (lisa) is a highly parallelizable numerical scheme for guided wave simulation in structural health monitoring (shm). this paper addresses the issue of simulating wave propagation in unbounded domain through the implementation of non-reflective boundary (nrb) in lisa. in this study,... | a hybrid non-reflective boundary technique for efficient simulation of guided waves using local interaction simulation approach |
transformation method provides an efficient tool to control wave propagation inside the materials. using the coordinate transformation approach, we study invisibility cloaks with sphere, cylinder and ellipsoid structures for electronic waves propagation. the underlying physics behind this investigation is the fact that... | coordinate transformations and matter waves cloaking |
the propagation of waves in helical rods has been studied extensively. however, studying the wave propagation in double helical rods have received less attention although this can be useful in multiple fields of science and engineering. obtaining an analytical model for a double helical rod is challenging since the cur... | wave propagation in double helical rods |
the objective of the proposed research project is to develop a non-destructive test technique based on stress wave for quantitative evaluation of the repairing status of concrete. concrete structures frequently exist various types of cracks due to an inferior environment and excessive loading. there are several crack r... | evaluation of repair quality for concrete structure by non-destructive technique |
active thermography is a well-established non-destructive testing method and used to detect cracks, voids or material inhomogeneities. it is based on applying thermal energy to a samples' surface whereas inner defects alter the nonstationary heat flow. conventional excitation of a sample is hereby done spatially, eithe... | spatial and temporal control of thermal waves by using dmds for interference based crack detection |
in the context of elastic wave propagation, the non-periodic homogenization asymptotic method allows to find a smooth effective medium and equations that correspond to the wave propagation in a given complex elastic or acoustic medium down to a given minimum wavelength. by smoothing all discontinuities and fine scales ... | residual homogenization for elastic wave propagation in complex media |
a fast scheme based on the multi-level substructure technique is proposed for the band structure and transmission characteristics calculation of phononic crystals uniformly. the main idea is that finite element models of phononic crystals are divided into several domains by a special multi-level decomposition. for the ... | band structure and transmission characteristics of complex phononic crystals by multi-level substructure scheme |
modeling laser-plasma interaction (lpi) processes in real-size experiments scale is recognized as a challenging task. for explorering the influence of various instabilities in lpi processes, a three-dimensional laser and plasma code (lap3d) has been developed, which includes filamentation, stimulated brillouin backscat... | the development of laser-plasma interaction program lap3d on thousands of processors |
three acoustic probe configurations were used to assess cyclic-tension fatigue in ss400 steel at room temperature via a diffracted horizontally polarized shear wave (sh) transmission method. linear analysis of the propagation time and amplitude of shear and longitudinal waves with fatigue progression revealed that the ... | cyclic-tension fatigue behavior in a ss400 steel plate studied using ultrasonic linear and nonlinear techniques |
at high frequency, diffraction during ionospheric propagation can yield wavefronts whose amplitude and phase fluctuate over the physical dimensions of phased array radars such as those of the super dual auroral radar network (superdarn). distortion in the wavefront introduces amplitude and phase scintillation into the ... | application of adaptive optics to scintillation correction in phased array high-frequency radar |
initiation of fourth generation (4g) mobile telecommunication system rollouts fires the starting pistol for beyond 4g research activities. whereas technologies enhancing spectral efficiency have traditionally been the solution to data rate and network capacity increase demands, due to the already advanced techniques, r... | on the 5g wireless communications at the low terahertz band |
the shear wave dispersion magneto-motive ultrasound (sdmmus) method was recently developed to analyze the mechanical properties of a viscoelastic medium. this technique is based on the interaction of magnetic nanoparticles (mnps) with an external magnetic field to generate a shear wave within the medium labeled with mn... | the effect of magnetization of natural rubber latex-coated magnetite nanoparticles on shear wave dispersion magneto-motive ultrasound |
by adopting reduction perturbation techniques, weakly non-linear wave equation in bubbly viscoelastic liquid flow is derived. viscosity, elasticity and surface tension are considered under isothermal condition. a kink travelling wave solution is obtained using tangent hyperbolic method combined with ricatti equation. g... | shock wave propagation in monodispersed bubbly viscoelastic fluid flow |
we demonstrate the meta-gate controlled wave propagation through multiple metallic plates with properly devised sub-wavelength defect apertures. different from using gradient refractive-index meta-materials or phase-discontinuity meta-surfaces to produce the discrepancy between the incident angle and the refractive ang... | meta-gated channel for the discrete control of electromagnetic fields |
this paper investigates the free transverse vibration of a wrinkled annular thin film. the non-dimensional hamilton motion equation of the wrinkled annular thin film is established, which is solved by using the finite difference method to acquire the vibration frequency and mode. the predicted vibration characteristics... | free transverse vibration of a wrinkled annular thin film by using finite difference method |
we study the average energy - or particle - density of waves inside disordered 1d multiply-scattering media. we extend the transfer-matrix technique that was used in the past for the calculation of the intensity beyond the sample to study the intensity in the interior of the sample by considering the transfer matrices ... | reprint of : connection between wave transport through disordered 1d waveguides and energy density inside the sample: a maximum-entropy approach |
in recent years, the technology of using laser ultrasonic propagation imaging for damage visualization of composite structures were applied to real-world applications. among many choices of sensor for the ultrasonic propagation imager, the laser interferometry has several advantages: it is non-invasive, and portable, a... | snr enhancement for composite application using multiple doppler vibrometers based laser ultrasonic propagation imager |
the couple stress theory developed by eringen comprises granular materials as also composite fibrous materials. as such, micropolar materials present an inclusive model of composite materials. this article endeavors to study aspects of wave propagation in a random weakly thermal micropolar elastic medium. the smooth pe... | on wave propagation in a random micropolar thermoelastic medium, second moments, and associated green's tensor |
shock waves resulting from irradiation of energetic materials with a pulsed ultraviolet laser source have been shown to be an effective indicator for explosives detection. here, the features of shock wave propagation are explored theoretically. the initial stage of the shock motion is simulated as a one-dimensional pro... | a numerical study of shock waves generated through laser ablation of explosives |
with the advent of coherent x-ray sources, x-ray refraction has begun to be utilized for x-ray imaging of unprecedented sensitivity. the aim of this study was to develop a wave propagation simulator that provides a map of x-ray refraction after passing through an object. we applied the fresnel diffraction integral for ... | wave propagation simulation based on the fourier diffraction integral for x-ray refraction contrast imaging-computed tomography |
a lamb wave-based, subwavelength imaging algorithm is developed for damage imaging in large-scale, plate-like structures based on a decomposition of the time-reversal operator (dort) method combined with the multiple signal classification (music) algorithm in the space-frequency domain. in this study, a rapid, hybrid n... | lamb waves based fast subwavelength imaging using a dort-music algorithm |
the present article studies the of love-type wave propagation in irregular functionally graded piezoelectric material (fgpm) resting over elastic half-space with irregular boundary. perturbation method has been employed in solution part when dealing with equations of motion that manifests the velocity profile of love t... | on the transference of love-type waves in pre-stressed pzt-5h material stick on sio2 material with irregularity |
in this paper, we consider a pressure-velocity formulation of the heterogeneous wave equation and employ the constraint energy minimizing generalized multiscale finite element method (cem-gmsfem) to solve this problem. the proposed method provides a flexible framework to construct crucial multiscale basis functions for... | computational multiscale methods for first-order wave equation using mixed cem-gmsfem |
driven by the need for describing and understanding wave propagation in structural materials and components, several analytical, numerical, and experimental techniques have been developed to obtain dispersion curves. accurate characterization of the structure (waveguide) under test is needed for analytical and numerica... | estimating dispersion curves from frequency response functions via vector-fitting |
we have analyzed hα intensity images obtained at a 1 minute cadence with the global oscillation network group (gong) system to investigate the properties of oscillations in the 0-8 mhz frequency band at the location and time of strong m- and x-class flares. for each of three subregions within two flaring active regions... | temporal evolution of chromospheric oscillations in flaring regions: a pilot study |
we will study high-frequency wave propagation in periodic media. a typical example is given by the schrodinger equation in the semiclassical regime with a highly oscillatory periodic potential and external smooth potential. this problem presents a numerical challenge when in the semiclassical regime. for example, conve... | semiclassical methods for high frequency wave propagation in periodic media |
in this paper, we examine the correlation functions associated with intensity interferometry and gravito-optics of gravitational wave (gw) signals from compact binary coalescences (cbc). previous theoretical studies of the gravito-optics of gws have concentrated on the characterization of both the classical and the non... | gravito-optics and intensity correlations for binary inspiral signal detections |
this paper introduces a general technique for inter-mapping the complex spatial frequency (or propagation constant) $\gamma=\alpha+j\beta$ and the temporal frequency $\omega = \omega_\text{r}+j\omega_\text{i}$ of an arbitrary electromagnetic structure. this technique, based on the analytic property of complex functions... | general mapping between complex spatial and temporal frequencies by analytical continuation |
in this paper, elastic wave propagation and inertia effects in gelatin-based soft material under impact loading is investigated. the dynamic test is principally performed by the classical shpb (split hopkinson pressure bars) technique with highly sensitive piezoelectric polyvinylidene fluoride (pvdf) pressure sensors p... | experimental investigation of elastic wave propagation and inertia effects in extra soft gelatin material |
a method of incorporating pressure forcing into a nonlinear potential flow wave model is presented. a semi-analytical pseudo-spectral method is used to calculate dynamic response of a water body exposed to evolving local pressure distribution. surface slope coherent and slope proportional pressure functions are directl... | on pressure forcing techniques for numerical modelling of unidirectional nonlinear water waves |
dispersion curve, and displacement modeshapes of multilayer structures can be obtained using semi-analytical finite element (safe) method. stress mode shapes calculated from safe were discontinuous at the interface, because safe method formulation does not apply stress continuity at the interface. a case study of 1 mm ... | hybrid safe-gmm approach for predictive modeling of guided wave propagation in layered media |
leakage of oil and gas pipe systems, water pipes and other pipe networks can cause serious environmental, health and economic problems. in order to minimise the damages brought to the environment, human health and the economic issues, rapid non-destructive detection of pipeline leakage is imperative. in recent works, n... | simulation and experimental measurement of acoustic wave reflectometry for leak detection in pipes |
stiffness at very small strains g0 is commonly assessed by way of laboratory and field methods, and used to design a wide range of infrastructure. when stiffness is inferred from field measurements, its value depends on the soil suction and state of saturation at the time of the measurement, and models are needed to in... | a microscale-based model for small-strain stiffness in unsaturated granular geomaterials |
conventional ultrasound inspection has been a standard non-destructive testing method for providing an in-service evaluation and noninvasive means of probing the interior of a structure. in particular, measurement of the propagation characteristics of lamb waves allows inspection of plates that are typical components i... | lamb wave dispersion and anisotropy profiling of composite plates via non-contact air-coupled and laser ultrasound |
hepatocyte transplantation has been considered and investigated as a promising and alternative method to liver transplantation for treating liver-based metabolic disorder in newborns over the past two decades. although some clinical trials have been conducted and shown clinical benefits and outcomes, it is difficult to... | ultrasonic histotripsy for tissue therapy |
the extended simple equation method is applied to construct solitary wave solutions of (3 + 1)-dimensional kadomtsev-petviashvili-benjamin-bona-mahony (kp-bbm), korteweg-de vries benjamin-bona-mahony (kdv-bbm), breaking soliton (bs) and (2 + 1) maccari system waves system of equations. these models have prevalent usage... | applications of modified mathematical method on some nonlinear water wave dynamical models |
magnetic resonance-guided high intensity focused ultrasound (mr-hifu) is a noninvasive thermal technique that enables rapid heating of a specific area in the human body. its clinical relevance has been proven for the treatments of soft tissue tumors, like uterine fibroids, and for the treatments of solid tumors in bone... | modeling the interference between shear and longitudinal waves under high intensity focused ultrasound propagation in bone |
this paper acquaints the investigations using rayleigh waves to surveil the structural integrity of an t-beam. unlike the conventional contact-type of sensors, such as the piezoelectric transducers and magnetostrictive sensors, a fully non-contact 3d type of laser-based transduction system was used in the present study... | feasibility of using a 3d laser-based transduction system for monitoring the integrity of i-beams using rayleigh waves |
ultrasonic guided wave (gw) inspection is one of the non-destructive testing (ndt) techniques available for the engineering structures. compared with other ndt techniques, guided waves can propagate a long distance with a relatively high sensitivity to defects in the structure. in order to increase the performance for ... | an analytical model of transducer array arrangement for guided wave excitation and propagation on cylindrical structures |
zero- and longitudinal-field muon spin relaxation (zf-, lf-μsr) measurements were carried out on the spin-1/2 kagome lattice antiferromagnet (rb1-xcsx)2cu3snf12 with x = 0.53 and 0.6, where xc = 0.53 is the quantum critical point between the antiferromagnetically ordered phase and the valence-bond-glass phase. in the c... | spin fluctuations in the spin-1/2 kagome lattice antiferromagnet (rb1-xcsx)2cu3snf12 around the quantum critical point detected by muon spin relaxation technique |
geologic studies indicate that the platform-margin reef-shallow facies in permo-triassic marine strata in the micang-dabashan foothill belt in the sichuan basin are favorable exploration targets for oil and gas exploration. however, the typical dual-complexity problem (complex surface condition and subsurface structure... | an introduction to seismic exploration of the micang-dabashan foothill belt in the sichuan basin |
this paper presents data about experimental observation and theoretical validation effect of native defect states activated by illumination and under the memory effect conditions on the velocity of longitudinal and shear elastic waves propagating in layered tlins2 ferroelectric-semiconductor in different directions. th... | influence of native structural defects activated by illumination and under the memory effect conditions on ultrasonic wave propagation in tlins2 ferroelectric-semiconductor with incommensurate phase |
future space-mission concepts currently discussed in the helioseismology community are reviewed. one popular idea is to observe the sun from high latitudes, to explore the polar regions as well as to probe the deep interior using stereoscopic techniques, by combining observations from high latitudes with observations f... | future mission concepts for helioseismology |
myocardial infarction (mi) is a leading cause of death and decrease of quality of life in the usa. an immense amount of research and development has been focused on the molecular mechanisms associated with mi, which have led to numerous therapies for treating and repairing cardiac tissue after mi. however, there is a r... | assessment of the biomechanical changes in cardiac tissue after myocardial infarction with optical coherence elastography |
this thesis investigates a method of tracking remote transmitters using multipath localization ?ngerprints generated by a ray tracing simulation. radio wave propagation phenomena in a dense urban environment can be simulated using publicly available mapping data and 2-d ray tracing techniques when the receivers and tra... | design of a covariance matrix fitter to measure the electron antineutrino oscillation parameters using neutron hydrogen capture at the daya bay experiment |
the assessment of creep degradation in a 9%cr heat-resistant steel welded joint has been carried out by means of nonlinear ultrasonic and traditional linear ultrasonic technique. the ultrasonic measurements were conducted at several regions of welded joint, which include the wm, haz, and bm. the experimental results in... | creep degradation assessment in 9%cr heat-resistant steel welded joints using ultrasonic methods |
optical propagation in nonlinear media and the formation of optical vortices as dark holes have been intensively studied in modern optical physics. in this paper, we prove the existence of different types of stationary vortex wave solutions of a general class for nonlinear schrödinger equations. first, we prove the exi... | existence of vortices in nonlinear optics |
this paper discusses theoretical and experimental analyses of weld guided surface acoustic waves (saw) through the guided wave propagation (gwp) analyses. the gwp analyses have been carried out by utilizing piezoelectric wafer active sensors (pwas) for in situ structural inspection of a thick steel plate with butt weld... | quasi-rayleigh waves in butt-welded thick steel plate |
fractures and fracture networks play a significant role in the subsurface hydraulic connectivity within the earth. while a significant amount of research has been performed on the seismic response of single fractures and sets of fractures, few studies have examined the effect of fracture intersections on elastic wave p... | elastic waves along a fracture intersection |
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 |
investigation of dust acoustic waves is done in two different ways in a system of collision-less dissipative and un-magnetized four component dusty plasma. in the first situation we have both quantum positively and negatively charged dust grains along with quantum electron and maxwellian ions. and in the other situatio... | four component strongly coupled quantum dusty plasma and generation of dark-bright solitons and double-layers |
because the tsunami wavelength is much longer than the sea depth, the propagation of this powerful destructive wave can be modelled by the non-linear shallow water equations (swes). to solve accurately these hyperbolic partial differential equations, one can resort to a variety of numerical techniques, including finite... | explicit finite difference schemes for solving the one - dimensional tsunami wave propagation equations |
in marine seismic exploration, ocean-bottom cable techniques accurately record the multicomponent seismic wavefield; however, the seismic wave propagation in fluid-solid media cannot be simulated by a single wave equation. in addition, when the seabed interface is irregular, traditional finite-difference schemes cannot... | forward modeling of ocean-bottom cable data and wave-mode separation in fluid-solid elastic media with irregular seabed |
a statement and solving technique for the problem of axisymmetric wave propagation in an incompressible laminated composite material with initial stresses are considered in the framework of the three-dimensional linearized theory of elasticity for prestressed solids. the case of wave propagation along the layers is con... | axisymmetric waves in prestressed incompressible laminated composite materials with sliding layers |
water leakage is one of the important agendas across the globe thus several effectual systems for leakage detection had been developed with the aim to improve sustainable use of water. among the methods, acoustic leak detection technique had been proven as a promising approach to detect and localize leaks in water or g... | improvement of acoustic water leak detection based on dual tree complex wavelet transform-correlation method |
context.early magnetographic observations indicated that the magnetic field in the solar photosphere has an unresolved small-scale structure. near-infrared and optical data with extremely high spatial resolution show that these structures have scales of a few tens of kilometres, which are not resolved in the majority o... | analysis of unresolved photospheric magnetic field structure using fe i 6301 and 6302 lines |
the measurement of ultrasonic signals on a 2-d rectilinear grid resulting from a fixed source, referred to as wavefield imaging, is a powerful tool for visualizing wave propagation and scattering. wavefield imaging provides a more complete picture of wave propagation than conventional single-point measurements, but cre... | challenges in the separation and analysis of scattered waves in angle-beam wavefield data |
this paper investigates the orthotropic properties of fused deposition modeling (fdm)-printed acrylonitrile styrene acrylate (asa) material with different raster configurations. the elastic properties were determined using a non-destructive ultrasonic technique. this technique allows us to deduce the orthotropic elasti... | finite element analysis of 3d-printed acrylonitrile styrene acrylate (asa) with ultrasonic material characterization |
in this paper, the conditions for generating cumulative second harmonics of shear horizontal guided waves are provided. the partial wave technique and normal modal analysis method are used to analyze the second harmonic field. measurements of the accumulative growth of normalized second harmonic amplitudes of the shear... | second harmonic generation of shear horizontal guided wave propagation in plate-like structures |
a leading cause of death and decrease in the quality of life in the usa is myocardial infarction (mi). molecular and genetic analyses have revealed a plethora of information about critical processes involved with mi. however, there is a lack of accompanying information about cardiac tissue biomechanical properties, whi... | optical coherence elastography reveals the changes in cardiac tissue biomechanical properties after myocardial infarction in a mouse model |
schlieren and shadowgraph photography has been widely used to offer insight into the flow field in aerospace engineering due to their ease of application. the high-speed schlieren and shadowgraph techniques are typically applied to investigation of unsteady shock wave structure including shock reflection patterns and s... | image processing techniques for shock wave detection and tracking in high speed schlieren and shadowgraph systems |
fundamentals of optical waveguides is a needed resource for any researcher, concerned in optics and communications engineering. interested by designing or actively running with optical gadgets have to have a company hold close of the standards of light wave propagation. this paper presents an fft beam propagation metho... | design and simulation of the fourier transform beam propagation method in different optical waveguides |
holographic tomography (ht) enables measurement of three-dimensional refractive index distribution of transparent micro-objects by merging information from multiple transmitted waves corresponding to various illumination directions. ht has proven its great potential in technical inspection and biomedical studies; nonet... | comparative analysis of feedback methods in reconstruction algorithms for multiple-scattering holographic tomography |
this article addresses the importance of accurate characterization of plasma parameters for electromagnetic compatibility (emc) purposes. most of emc issues involving plasma materials are obviously multi-physics problems (linking chemical, mechanical, thermal and electromagnetic wondering) with deep interactions. one o... | air plasma key parameters for electromagnetic wave propagation at and out of thermal equilibrium: applications to electromagnetic compatibility |
the sparse approximation of high-frequency helmholtz-type integral operators has many important physical applications such as problems in wave propagation and wave scattering. the discrete system matrices are huge and densely populated; hence their sparse approximation is of outstanding importance. in our paper we will... | variable order, directional h2-matrices for helmholtz problems with complex frequency |
we develop a compact perturbative series for acoustic wave propagation in a medium with a non-gaussian stochastic speed of sound. we use martin-siggia and rose auxiliary field techniques to render the classical wave propagation problem into a ‘quantum’ field theory one, and then frame this problem within the so-called ... | wave propagation in non-gaussian random media |
context. magnetohydrodynamic (mhd) waves are ubiquitous in the solar corona where the highly structured magnetic fields provide efficient wave guides for their propagation. while mhd waves have been observed originating from lower layers of the solar atmosphere, recent studies have shown that some can be generated in s... | mhd simulations of the in situ generation of kink and sausage waves in the solar corona by collision of dense plasma clumps |
numerical simulation of flow problems and wave propagation in heterogeneous media has important applications in many engineering areas. however, numerical solutions on the fine grid are often prohibitively expensive, and multiscale model reduction techniques are introduced to efficiently solve for an accurate approxima... | constraint energy minimizing generalized multiscale discontinuous galerkin method |
effective medium theory aims to describe a complex inhomogeneous material in terms of a few important macroscopic parameters. to characterise 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 |
a time-distance helioseismic technique, similar to the one used by ilonidis et al., is applied to two independent numerical models of subsurface sound-speed perturbations to determine the spatial resolution and accuracy of phase travel time shift measurements. the technique is also used to examine pre-emergence signatu... | analysis of time-distance helioseismology for detection of emerging active regions |
voronoi tessellation theory is applied to model the cells and ligaments in the open aluminum foam material. the cores of the cells are first generated by packing random spheres into the specified spatial domain. weighted voronoi tessellation is then applied to make the cellular structure of the foam material. for the o... | a numerical method for the ballistic performance prediction of the sandwiched open cell aluminum foam under hypervelocity impact |
the newly discovered atomically thin and layered materials which host electronic system that respond to longwavelength light in extraordinary manner can lead to a major breakthrough in the field of terahertz (thz) optics and photonics. however, their low conductivities due to either low densities or low mobility make i... | parallel plate waveguide time domain spectroscopy to study terahertz conductivity of utltrathin materials |
presented is a study of the effect of frequency of cyclic soaking and drying on the time variation of resilient modulus mr of gypsum-rich roadbed sand having a gypsum content of about 39%. three different frequencies are adopted. the high frequency is represented by a short cycle length of 14 days, while for the low an... | frequency effect of cyclic soaking and drying on the resilient modulus of gypsum-rich roadbed sand |
based on high order hierarchical basis function and the ideal of shift operator, shift operator discontinuous galerkin time domain (so-dgtd) technique for dealing with weakly ionized dusty plasma electromagnetic problems is proposed. lagrange interpolation is used to transform the metallic blunt cone aircraft with weak... | analysis of the transmission characteristics of radio waves in inhomogeneous weakly ionized dusty plasma sheath based on high order so-dgtd |
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