We described an implementation of differential semblance velocity analysis based on shot-profile migration, and illustrated its ability to estimate complex, strongly refracting fields. The approach uses waveform data directly: it does not require any sort traveltime picking. objective function minimized by the algorithm can measure either focusing image in offset or flatness (scattering) angle. showed that variant yields somewhat more reliable migration estimates than scattering angle...

Shanghai Pudong International Airport (PDIA), with its east side built along the coast weak geological conditions, is prone to uneven foundation settlement due consolidation and compression of soil erosion coastal tides, affecting safe operation airport. Therefore, it crucial conduct dynamic subsidence monitoring within airport, especially in runway area. 29 scenes ascending track Sentinel-1A radar images from August 2016 June 2018 are selected perform surface deformation inversion based on...

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2003Differential semblance velocity analysis by wave‐equation migrationAuthors: Peng ShenWilliam W. SymesChristiaan C. StolkPeng ShenRice University, William SymesRice and Christiaan StolkÉcole Polytechniquehttps://doi.org/10.1190/1.1817759 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Permalink:...

Summary We show an explicit scheme that separates seismic source and receiver wave-fields individually into up- down- going components. The main challenge of the work is generating correspond to positive or negative temporal frequencies in space-time 4D volume. This difficulty arises because propagators we typically employ store with slowest dimension time but Fourier transform operates most efficiently on data are stored contiguously. solve this issue by a Hilbert term wave-equation...

A kinematically correct choice of velocity focuses subsurface offset image gathers at a zero offset. Infinitesimal warping from the current toward its focus can be approximated by horizontal contraction. The residual then taken as difference between warped and original to account for error. Least-squares fitting effect perturbation this image-warping produces tomographic update. We evaluated scheme based on radial derivative in found that corresponding gradient was free diffraction edge...

In seismic tomography, the finite frequency content of broad-band data leads to interference effects in process medium reconstruction, which are ignored traditional ray theoretical implementations. Various ways looking at these framework transmission tomography can be found literature. Here, we consider inverse scattering body waves develop a method wave-equation reflection with waveform data—which exploration seismics is identified as migration velocity analysis. transition from usual cross...

Purpose – This paper aims to provide theoretical analysis and empirical study on the relationship between training organizational commitment; analyze mediating role of employability moderating expectation value in their relationship; draw from both these suggest practical implications organizations aiming effectively train retain employees, for employees themselves. Design/methodology/approach First, reviews literature regarding training, employability, commitment value. Second, it develops...

With the increasing of satellite sensors, more available multi-source data can be used for large-scale high-precision crop classification. Both polarimetric synthetic aperture radar (PolSAR) and multi-spectral optical have been widely However, it is difficult to combine covariance matrix PolSAR with spectral bands data. Using Hoekman's method, this study solves above problems by transforming an intensity vector that includes multiple values on different polarization basis. In order reduce...

A continuous-flow output mode of a rotary blood pump reduces the fluctuation range arterial pressure and easily causes complications. For centrifugal pump, sinusoidal pulsatile speed patterns are designed using impeller modulation. This study aimed to analyze hemodynamic characteristics hemolysis different in patients with heart failure computational fluid dynamics (CFD) lumped parameter model (LPM). The results showed that three (including constant pattern) met normal demand human body....

Shot profile migration provides a convenient framework for implementation of differential semblance algorithm estimation complex, strongly refracting velocity fields. The objective function minimized in this may measure either focussing the image offset or flatness (scattering) angle. gradient is by‐product depth marching scheme, an requires few extra computations beyond those necessary to produce prestack data volume. A 2D synthetic example illustrates excellent quality obtainable from...

Abstract The long‐term temperature induced errors caused by fiber λ/4 wave plate and the Verdet constant of sensing in all current transformer (FOCT) are theoretically analyzed. A related response is adopted to compensate for change through choosing appropriate initial phase retardation plate. experimental results show high temperature‐cycle accuracy this kind FOCT with relative error within 0.6%.

Forest above ground biomass (AGB) extraction using Synthetic Aperture Radar (SAR) images has been widely used in global carbon cycle research. Classical AGB inversion methods SAR are mainly based on backscattering coefficients. The polarization coherence tomography (PCT) technology which can generate vertical profiles of forest relative reflectivity, the potential to improve accuracy inversion. relationship between and is modeled by some parameters defined geometric characteristics...

The traditional nonlocal filters for polarimetric synthetic aperture radar (PolSAR) images are based on square patches matching to obtain homogeneous pixels in a large search window. However, it is still difficult the regular work well complex textured areas, even when patch size has small enough setting (e.g., 3 × windows). Therefore, this paper proposes an adaptive mean filter with shape-adaptive (ANLM) PolSAR images. Mainly, (SA) constructed by combining likelihood ratio test coherency...

A weighted subspace-constrained minimum variance distortion-less response (WS-MVDR) beamformer is proposed for robustly controlling the peak sidelobe level (PSL) as well shape of adaptive array pattern with stable mainlobe. The weight vector projected onto subspace constructed from steering vectors. norm projection constrained below derived constant value determined by desired PSL. only inequality constraint introduced to conventional MVDR beamformer, resulting in a second-order cone...

Distinguished from the classical Full Waveform Inversion, objective functions for migration velocity analysis can be posed in image domain whose gradient with respect to computed a Reverse Time Migration setting. The focus of this paper is an RTM based computation kind. A quasi-Newton method applied inversion. It shown that both diving waves and reflections make focussed sub-surface offset as gradually converges true by Examples 2d synthetic data 3d real demonstrate robustness proposed.

A novel method based on the optimal normal matrix constraint and cross-iteration algorithm is proposed in this letter to estimate forest height using polarimetric interferometry synthetic aperture radar (PolInSAR) data. First, avoid null ground-to-volume ratio assumption of three-stage method, we use PolInSAR find out pure volume coherence. This can also provide a more accurate initial value for least-squares iteration. Second, used inversion, which provides better selection best...

Interferometric phase optimization is important key processing for ensuring the application performance of interferometric synthetic aperture radar (InSAR) technology. The noise’s standard deviation depends on number looks and coherence magnitude. Usually, estimation uses statistical averaging with spatial samples to reduce speckle noise in images. It has been demonstrated that polarization plays a significant role variation complex coherence. Currently, InSAR technology utilizes...

With the launch of various multipolarimetric satellites, many scholars have introduced persistent scatterer (PS)-oriented polarimetric optimization methods and extended interferometry (PSI) method to data configuration, called PSI (PolPSI) technology. Most PolPSI mainly take amplitude dispersion index (ADI) as criterion evaluate temporal stationarity each channel for finding an optimal one. However, due unstable statistical characteristics quality indicator, non-PS pixels are easily mistaken...

The ray paths for a given velocity model and acquisition geometry can be reconstructed within the approach of wave‐equation migration in shot domain, mechanism called this paper adjoint state differential (ASDM). image residual defined by semblance operator propagated ASDM to create constructive interferences through correlation wavfields their corresponding forward wavefields, result is construction path along which smoothly distributed. In particular, receiver wavefield, denoted gr...