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Adaptive Maxwell’s Equations Derived Optimization and Its Application in Antenna Array Synthesis 被引量:1
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作者 Donglin Su Lilin Li +1 位作者 Shunchuan Yang Fei Wang 《China Communications》 SCIE CSCD 2021年第5期263-272,共10页
In this paper,a self-adaptive method for the Maxwell’s Equations Derived Optimization(MEDO)is proposed.It is implemented by applying the Sequential Model-Based Optimization(SMBO)algorithm to the iterations of the MED... In this paper,a self-adaptive method for the Maxwell’s Equations Derived Optimization(MEDO)is proposed.It is implemented by applying the Sequential Model-Based Optimization(SMBO)algorithm to the iterations of the MEDO,and achieves the automatic adjustment of the parameters.The proposed method is named as adaptive Maxwell’s equations derived optimization(AMEDO).In order to evaluate the performance of AMEDO,eight benchmarks are used and the results are compared with the original MEDO method.The results show that AMEDO can greatly reduce the workload of manual adjustment of parameters,and at the same time can keep the accuracy and stability.Moreover,the convergence of the optimization can be accelerated due to the dynamical adjustment of the parameters.In the end,the proposed AMEDO is applied to the side lobe level suppression and array failure correction of a linear antenna array,and shows great potential in antenna array synthesis. 展开更多
关键词 electromagnetic compatibility Maxwell’s equations derived optimization adaptive Maxwell’s equations derived optimization sequential modelbased optimization antenna array synthesis
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Finite Parameter Solutions to the Manakov and the Derivative Manakov Equations
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作者 曹建莉 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期236-244,共9页
Finite-dimensional integrable Hamiltonian systems, obtained through the non- linearization of the 3×3 spectral problems associated with the Manakov and the derivative Manakov equations, are investigated. A genera... Finite-dimensional integrable Hamiltonian systems, obtained through the non- linearization of the 3×3 spectral problems associated with the Manakov and the derivative Manakov equations, are investigated. A generating function method is used to give a simple and effective way to prove the involutivity of integrals. Finite-parameter solutions of the Manakov and the derivative Manakov equations are calculated based on the commutative systems of ordinary differential equations with these integrals as Hamiltonians. 展开更多
关键词 the Manakov equation the derivative Manakov equation the involutivity of conserved integrals
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Solution of Partial Derivative Equations of Poisson and Klein-Gordon with Neumann Conditions as a Generalized Problem of Two-Dimensional Moments
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作者 Maria B. Pintarelli 《Journal of Applied Mathematics and Physics》 2020年第8期1606-1614,共9页
It will be shown that finding solutions from the Poisson and Klein-Gordon equations under Neumann conditions are equivalent to solving an integral equation, which can be treated as a generalized two-dimensional moment... It will be shown that finding solutions from the Poisson and Klein-Gordon equations under Neumann conditions are equivalent to solving an integral equation, which can be treated as a generalized two-dimensional moment problem over a domain that is considered rectangular. The method consists to solve the integral equation numerically using the two-dimensional inverse moments problem techniques. We illustrate the different cases with examples. 展开更多
关键词 Equation in Poisson Partial Derivatives Klein-Gordon Equation Integral equations Generalized Moment Problem
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N-Soliton Solutions of General Nonlinear Schrdinger Equation with Derivative 被引量:6
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作者 ZHAI Wen CHEN Deng-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1101-1104,共4页
The bilinear equation of the genera/nonlinear Schrodinger equation with derivative (GDNLSE) and the N-soliton solutions are obtained through the dependent variable transformation and the Hirota method, respectively.... The bilinear equation of the genera/nonlinear Schrodinger equation with derivative (GDNLSE) and the N-soliton solutions are obtained through the dependent variable transformation and the Hirota method, respectively. The bilinear equation of the nonlinear Schrodinger equation with derivative (DNLSE) and its multisoliton solutions are given by reduction. 展开更多
关键词 general nonlinear Schrodinger equation with derivative nonlinear SchrSdinger equation withderivative Hirota method
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Solitary Wave Solutions of a Generalized Derivative Nonlinear Schrdinger Equation 被引量:1
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作者 WANG Ming-Liang ZHANG Jin-Liang LI Xiang-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期39-42,共4页
With the aid of a class of nonlinear ordinary differential equation (ODE) and its various positive solutions, four types of exact solutions of the generalized derivative nonlinear Sehrodinger equation (GDNLSE) hav... With the aid of a class of nonlinear ordinary differential equation (ODE) and its various positive solutions, four types of exact solutions of the generalized derivative nonlinear Sehrodinger equation (GDNLSE) have been found out, which are the bell-type solitary wave solution, the algebraic solitary wave solution, the kink-type solitary wave solution and the sinusoidal traveling wave solution, provided that the coefficients of GDNLSE satisfy certain constraint conditions. For more general GDNLSE, the similar results are also given. 展开更多
关键词 generalized derivative nonlinear Schrodinger equation bell-type solitary wave kink-type solitary wave sinusoidal traveling wave
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On Skew Triangular Matrix Rings 被引量:3
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作者 Wang Wei-liang Wang Yao Ren Yan-li 《Communications in Mathematical Research》 CSCD 2016年第3期259-271,共13页
In this paper, we prove the existence and uniqueness of positive solutions for a system of multi-order fractional differential equations. The system is used to represent constitutive relation for viscoelastic model of... In this paper, we prove the existence and uniqueness of positive solutions for a system of multi-order fractional differential equations. The system is used to represent constitutive relation for viscoelastic model of fractional differential equations. Our results are based on the fixed point theorems of increasing operator and the cone theory, some illustrative examples are also presented. 展开更多
关键词 fractional differential equation Caputo fractional derivative fixed point theorem positive solution
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Correcting the initialization of models with fractional derivatives via history-dependent conditions 被引量:1
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作者 Maolin Du Zaihua Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第2期320-325,共6页
Fractional differential equations are more and more used in modeling memory(history-dependent,nonlocal,or hereditary) phenomena.Conventional initial values of fractional differential equations are define at a point,... Fractional differential equations are more and more used in modeling memory(history-dependent,nonlocal,or hereditary) phenomena.Conventional initial values of fractional differential equations are define at a point,while recent works defin initial conditions over histories.We prove that the conventional initialization of fractional differential equations with a Riemann–Liouville derivative is wrong with a simple counter-example.The initial values were assumed to be arbitrarily given for a typical fractional differential equation,but we fin one of these values can only be zero.We show that fractional differential equations are of infinit dimensions,and the initial conditions,initial histories,are define as functions over intervals.We obtain the equivalent integral equation for Caputo case.With a simple fractional model of materials,we illustrate that the recovery behavior is correct with the initial creep history,but is wrong with initial values at the starting point of the recovery.We demonstrate the application of initial history by solving a forced fractional Lorenz system numerically. 展开更多
关键词 Fractional derivative Differential equation Initial value Initial history
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Air flow calculation of reverse circulation drilling technique with air DTH hammer 被引量:1
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作者 HUANG Yong ZHU Lihong +1 位作者 YIN Kun BO Kun 《Global Geology》 2010年第3期165-170,共6页
Air DTH hammer has been successfully applied in minor-caliber solid mineral exploration,water-well drilling and other drilling areas. In order to expand the applications of the technology,the authors further studied t... Air DTH hammer has been successfully applied in minor-caliber solid mineral exploration,water-well drilling and other drilling areas. In order to expand the applications of the technology,the authors further studied the principle and analyzed the mechanism of reverse circulation drilling technique with air DTH hammer to get the perfect assembles of equipments by optimizing working parameters. No parameter seemed more important than the air volume because it could maintain the working performance stability. The minimum air volume is related to the parameters such as depth and pressure,which was calculated under the actual conditions. It was solved for the air injection flow tables of the air DTH Hammer working at the different pressures. According to the data tables,operators could adjust the air volume to meet the demand on this technique,which had a realistic guiding significance. So it could build up a set of systematic and complete hi-technique. 展开更多
关键词 air DTH Hammer reverse circulating bit CFD simulation derivation equation air flow calculation
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ON SOLVABILITY OF A BOUNDARY VALUE PROBLEM FOR A NONHOMOGENEOUS BIHARMONIC EQUATION WITH A BOUNDARY OPERATOR OF A FRACTIONAL ORDER 被引量:2
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作者 A.S.BERDYSHEV A.CABADA B.Kh.TURMETOV 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1695-1706,共12页
This paper is concerned with the solvability of a boundary value problem for a nonhomogeneous biharmonic equation. The boundary data is determined by a differential operator of fractional order in the Riemann-Liouvill... This paper is concerned with the solvability of a boundary value problem for a nonhomogeneous biharmonic equation. The boundary data is determined by a differential operator of fractional order in the Riemann-Liouville sense. The considered problem is a generalization of the known Dirichlet and Neumann problems. 展开更多
关键词 biharmonic equation boundary value problem fractional derivative the RiemannLiouville operator
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An unsymmetric constitutive equation for anisotropic viscoelastic fluid 被引量:2
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作者 Shifang Han 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第2期149-158,共10页
A continuum constitutive theory of corotational derivative type is developed for the anisotropic viscoelastic fluid-liquid crystalline (LC) polymers. A concept of anisotropic viscoelastic simple fluid is introduced.... A continuum constitutive theory of corotational derivative type is developed for the anisotropic viscoelastic fluid-liquid crystalline (LC) polymers. A concept of anisotropic viscoelastic simple fluid is introduced. The stress tensor instead of the velocity gradient tensor D in the classic Leslie-Ericksen theory is described by the first Rivlin-Ericksen tensor A and a spin tensor W measured with respect to a co-rotational coordinate system. A model LCP-H on this theory is proposed and the characteristic unsymmetric behaviour of the shear stress is predicted for LC polymer liquids. Two shear stresses thereby in shear flow of LC polymer liquids lead to internal vortex flow and rotational flow. The conclusion could be of theoretical meaning for the modern liquid crystalline display technology. By using the equation, extrusion-extensional flows of the fluid are studied for fiber spinning of LC polymer melts, the elongational viscosity vs. extension rate with variation of shear rate is given in figures. A considerable increase of elongational viscosity and bifurcation behaviour are observed when the orientational motion of the director vector is considered. The contraction of extru- date of LC polymer melts is caused by the high elongational viscosity. For anisotropic viscoelastic fluids, an important advance has been made in the investigation on the constitutive equation on the basis of which a seriesof new anisotropic non-Newtonian fluid problems can be addressed. 展开更多
关键词 Unsymmetric constitutive equation .Co-rotational derivative type.Anisotropic simple fluid . Liquid crystalline polymer .Extrusion- extensional flow
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N-Fold Darboux Transformation for a Nonlinear Evolution Equation 被引量:2
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作者 Yannan Zhao 《Applied Mathematics》 2012年第8期943-948,共6页
In this paper, we present a N-fold Darboux transformation (DT) for a nonlinear evolution equation. Comparing with other types of DTs, we give the relationship between new solutions and the trivial solution. The DT pre... In this paper, we present a N-fold Darboux transformation (DT) for a nonlinear evolution equation. Comparing with other types of DTs, we give the relationship between new solutions and the trivial solution. The DT presented in this paper is more direct and universal to obtain explicit solutions. 展开更多
关键词 Darboux Transformation Derivative Nonlinear Schrodinger Equation Explicit Solution
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Direct Perturbation Method for Derivative Nonlinear Schrdinger Equation
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作者 CHENG Xue-Ping LIN Ji HAN Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期501-504,共4页
We extend Lou's direct perturbation method for solving the nonlinear Schrodinger equation to the case of the derivative nonlinear Schrodinger equation (DNLSE). By applying this method, different types of perturbati... We extend Lou's direct perturbation method for solving the nonlinear Schrodinger equation to the case of the derivative nonlinear Schrodinger equation (DNLSE). By applying this method, different types of perturbation solutions are obtained. Based on these approximate solutions, the analytical forms of soliton parameters, such as the velocity, the width and the initial position, are carried out and the effects of perturbation on solitons are analyzed at the same time. A numerical simulation of perturbed DNLSE finally verifies the results of the perturbation method. 展开更多
关键词 direct perturbation method perturbed derivative nonlinear SchrSdinger equation
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Global asymptotical stability in a rational difference equation
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作者 LI Xian-yi LI Wei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第1期51-59,共9页
In this paper we prove a global attractivity result for the unique positive equilibrium point of a difference equation,which improves and generalizes some known ones in the existing literature.Especially,our results c... In this paper we prove a global attractivity result for the unique positive equilibrium point of a difference equation,which improves and generalizes some known ones in the existing literature.Especially,our results completely solve an open problem and some conjectures proposed in[1,2,3,4]. 展开更多
关键词 global asymptotic stability global attractivity Open problem and conjecture Schwartzian derivative rational difference equation
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The Interaction and Degeneracy of Mixed Solutions for Derivative Nonlinear Schrodinger Equation
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作者 Zhen Wu Shuwei Xu +1 位作者 Tingwang Wu Haoqi Zhou 《Journal of Applied Mathematics and Physics》 2019年第11期2650-2657,共8页
The mixed solutions of the derivative nonlinear Schr&#246;dinger equation from the trivial seed (zero solution) are derived by using the determinant representation. By adjusting the interaction and degeneracy of m... The mixed solutions of the derivative nonlinear Schr&#246;dinger equation from the trivial seed (zero solution) are derived by using the determinant representation. By adjusting the interaction and degeneracy of mixed solutions, it is possible to obtain different types of solutions: phase solutions, breather solutions, phase-breather solutions and rogue waves. 展开更多
关键词 Derivative Nonlinear Schrodinger Equation Mixed Solutions Phase Solutions Breather Solutions Rogue Waves
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Peregrine Rogue Waves Generated by the Interaction and Degeneration of Soliton-Like Solutions: Derivative Nonlinear Schrödinger Equation
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作者 Haoqi Zhou Shuwei Xu Maohua Li 《Journal of Applied Mathematics and Physics》 2020年第12期2824-2835,共12页
We study the Peregrine rogue waves within the framework of Derivative Nonlinear Schrödinger equation, which is used to describe the propagation of Alfven waves in plasma physics and sub-picosecond or femtosecond ... We study the Peregrine rogue waves within the framework of Derivative Nonlinear Schrödinger equation, which is used to describe the propagation of Alfven waves in plasma physics and sub-picosecond or femtosecond pulses in nonlinear optics. The interaction and degeneration of two soliton-like solutions and its relations for the breather solution have been analyzed. The Peregrine rogue waves have been considered from the two kinds of formation processes: it can be generated through the limitation of the infinitely large period of the breather solutions, and it can be interpreted as the soliton-like solutions with different polarities. As a special example, a special Peregrine rogue wave is generated by a breather solution and phase solution, which is given by the trivial seed (zero solution). 展开更多
关键词 Derivative Nonlinear Schrödinger Equation Breather Solution Phase Solution Soliton-Like Solutions Peregrine Rogue Waves Darboux Transformation
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Existence and Properties of Solutions for a Class of Fractional Differential Equations 被引量:1
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作者 Yong-qiang XU Shu-hong CHEN Zhong TAN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2021年第3期477-484,共8页
In this paper,we consider the initial value problem of a class of fractional differential equations.Firstly,we obtain the existence and uniqueness of the solutions by using Picard’s method of successive approximation... In this paper,we consider the initial value problem of a class of fractional differential equations.Firstly,we obtain the existence and uniqueness of the solutions by using Picard’s method of successive approximation.Then we discuss the dependence of the solutions on the initial value. 展开更多
关键词 EXISTENCE UNIQUENESS fractional derivative equations
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Dark Soliton Solutions of Space-Time Fractional Sharma–Tasso–Olver and Potential Kadomtsev–Petviashvili Equations
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作者 Ozkan Guner Alper Korkmaz Ahmet Bekir 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第2期182-188,共7页
Dark soliton solutions for space-time fractional Sharma–Tasso–Olver and space-time fractional potential Kadomtsev–Petviashvili equations are determined by using the properties of modified Riemann–Liouville derivat... Dark soliton solutions for space-time fractional Sharma–Tasso–Olver and space-time fractional potential Kadomtsev–Petviashvili equations are determined by using the properties of modified Riemann–Liouville derivative and fractional complex transform. After reducing both equations to nonlinear ODEs with constant coefficients, the tanh ansatz is substituted into the resultant nonlinear ODEs. The coefficients of the solutions in the ansatz are calculated by algebraic computer computations. Two different solutions are obtained for the Sharma–Tasso–Olver equation as only one solution for the potential Kadomtsev–Petviashvili equation. The solution profiles are demonstrated in 3D plots in finite domains of time and space. 展开更多
关键词 exact solution modified Riemann–Liouville derivative space-time fractional Sharma–Tasso–Olver equation space-time fractional potential Kadomtsev–Petviashvili equation
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Soliton Solution of the DNLS Equation Based on Hirota's Bilinear Derivative Transform 被引量:11
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作者 ZHOU Guoquan BI Xintao 《Wuhan University Journal of Natural Sciences》 CAS 2009年第6期505-510,共6页
Based on the method of Hirota's bilinear derivative transform, the derivative nonlinear Schrodinger equation with vanishing boundary condition has been directly solved. The oneand two-soliton solutions are given as t... Based on the method of Hirota's bilinear derivative transform, the derivative nonlinear Schrodinger equation with vanishing boundary condition has been directly solved. The oneand two-soliton solutions are given as two typical examples in the illustration of the general procedures and the concrete cut-off technique of the series-form solution, and the n-soliton solution is also attained by induction method. Our study shows their equivalence to the existing soliton solutions by a simple parameter transformation. The methodological importance of bilinear derivative transform in dealing with an integrable nonlinear equation has also been emphasized. The evolution of one and two-soliton solution with respect to time and space has been discussed in detail. The collision among the solitons has been manifested through an example of two-soliton case, revealing the elastic essence of the collision and the invariance of the soliton form and characteristics. 展开更多
关键词 SOLITON nonlinear equation derivative nonlinear Schrodinger equation Hirota's method bilinear derivative transform
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Exponential Attractor of the 3D Derivative Ginzburg-Landau Equation 被引量:4
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作者 Shu Juan LU Qi Shao LU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第5期809-828,共20页
In this paper, we consider a derivative Ginzburg-Landau-type equation with periodic initial-value condition in three-dimensional spaces. Sufficient conditions for existence and uniqueness of a global solution are obta... In this paper, we consider a derivative Ginzburg-Landau-type equation with periodic initial-value condition in three-dimensional spaces. Sufficient conditions for existence and uniqueness of a global solution are obtained by uniform a priori estimates of the solution. Furthermore, the existence of a global attractor and an exponential attractor with finite dimensions are proved. 展开更多
关键词 derivative Ginzburg-Landau equation global attractor exponential attractor Hausdorff dimension fractal dimension
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Applying accurate gradients of seismic wave reflection coefficients (SWRC) to the inversion of seismic wave velocities 被引量:3
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作者 LIU FuPing MENG XianJun +2 位作者 XIAO JiaQi WANG YuMei SHEN GuoQiang 《Science China Earth Sciences》 SCIE EI CAS 2012年第12期1953-1960,共8页
Through solving the Zoeppritz's partial derivative equations, we have obtained accurate partial derivatives of reflected coefficients of seismic wave with respect to Pand S-wave velocities.With those partial deriv... Through solving the Zoeppritz's partial derivative equations, we have obtained accurate partial derivatives of reflected coefficients of seismic wave with respect to Pand S-wave velocities.With those partial derivatives, a multi-angle inversion is developed for seismic wave velocities.Numerical examples of different formation models show that if the number of iterations goes over 10, the relative error of inversion results is less than 1%, whether or not there is interference among the reflection waves.When we only have the reflected seismograms of P-wave, and only invert for velocities of P-wave, the multi-angle inversion is able to obtain a high computation precision.When we have the reflected seismograms of both P-wave and VS-wave, and simultaneously invert for the velocities of P-wave and VS-wave, the computation precisions of VS-wave velocities improves gradually with the increase of the number of angles, but the computation precision of P-wave velocities becomes worse.No matter whether the reflected seismic waves from the different reflection interface are coherent or non-coherent, this method is able to achieve a higher computation precision.Because it is based on the accurate solution of the gradient of SWRCs without any additional restriction, the multi-angle inversion method can be applied to seismic inversion of total angles.By removing the difficulties caused by simplified Zoeppritz formulas that the conventional AVO technology struggles with, the multiangle inversion method extended the application range of AVO technology and improved the computation precision and speed of inversion of seismic wave velocities. 展开更多
关键词 Zoeppritz’s partial derivative equations inversion of seismic wave velocity grads of seismic wave reflection coefficients (SWRCs) multi-angle inversion
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