Results 51 to 60 of about 3,552,226 (242)
International Journal of Geophysics, 2014 The present paper conducts a scientific review on ionospheric absorption, extrapolating the research prospects of a complex eikonal model for one-layer ionosphere.
Alessandro Settimi +3 more
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Quadratic Theory of Gravity with a Scalar Field and Type I Shapovalov Wave Spacetimes
Universe, 2022 For the quadratic theory of gravity with a scalar field, exact solutions are found for gravitational-wave models in Shapovalov I-type spacetimes, which do not arise in models of the general theory of relativity.
Konstantin Osetrin +2 more
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Characteristic surface data for the eikonal equation [PDF]
Journal of Mathematical Physics, 1999 A method of solving the eikonal equation, in either flat or curved space–times, with arbitrary Cauchy data, is extended to the case of data given on a characteristic surface. We find a beautiful relationship between the Cauchy and characteristic data for the same solution, namely they are related by a Legendre transformation.
Newman, Ezra T., Perez, Alejandro
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Three-dimensional P-velocity model of the upper mantle of the Western Mediterranean
Геофизический журнал, 2012 The paper presents 3D P-velocity structure of the upper mantle beneath Western Mediterranean region. Taylor approximation of eikonal equation and wave equation proposed by V. S. Gey-ko have been used.
I. V. Bugaenko +3 more
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Dizhen xuebao, 2021 基于中国地震科学探测台阵在鄂尔多斯及周边地区布设的461个地震台为期2年的地震观测资料，采用背景噪声层析成像方法，研究获得了鄂尔多斯及周边地区5—46 s周期、分辨率高达0.3°×0.3°的瑞雷面波相速度分布图像。与基于程函方程的地震面波成像结果对比看出，噪声层析成像在较短周期具有明显的优势（5—16 s），可以获得更高分辨率的成像结果。短周期（5—10 s）的相速度分布揭示，河套盆地、太原盆地和运城盆地等均表现为显著的低速异常，表明这些盆地的新生代沉积较厚，临汾盆地为弱低速异常，推测其沉积层相对较薄 ...
Jing Liu +4 more
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Eikonal equations with discontinuities
Differential and Integral Equations, 1995 The authors consider the equation \(H(Du)= n(x)\) over an \(n\)-dimensional domain, where \(H\) is a convex functional, \(Du\) represents the \(x\)-gradient of \(u\) and \(n(x)\) is lower semicontinuous. A new notion of generalized solution for the problem under consideration is introduced and investigated from the variational approach.
Newcomb, Richard T., Su, Jianzhong
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An Approximation Scheme for an Eikonal Equation with Discontinuous Coefficient [PDF]
SIAM Journal on Numerical Analysis, 2014 We consider the stationary Hamilton-Jacobi equation where the dynamics can vanish at some points, the cost function is strictly positive and is allowed to be discontinuous. More precisely, we consider special class of discontinuities for which the notion of viscosity solution is well-suited.
Adriano Festa, Maurizio Falcone
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Bayesian inversion of log-normal eikonal equations
Inverse Problems, 2023 Abstract We study the Bayesian inverse problem for inferring the log-normal slowness function of the eikonal equation, given noisy observation data on its solution at a set of spatial points. We contribute rigorous proofs on the existence and well-posedness of the problem.
Zhan Fei Yeo, Viet Ha Hoang
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Eikonal equation-based earthquake location by using three seismic phases
, 2023 Based on numerical solving eikonal equation, we invert earthquake location by using the traveltimes of three phases.
Shaolin Liu (12992313)
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Fast Methods for Eikonal Equations: An Experimental Survey [PDF]
IEEE Access, 2019 The Fast Marching Method is a very popular algorithm to compute times-of-arrival maps (distances map measured in time units). Since their proposal in 1995, it has been applied to many different applications such as robotics, medical computer vision, fluid simulation, etc.
Javier V. Gómez +3 more
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