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Thermal investigation of water-based radiative magnetized micropolar hybrid nanofluid flow subject to impacts of the Cattaneo–Christov flux model on a variable porous stretching sheet with a machine learning approach
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作者 Showkat Ahmad Lone Zehba Raizah +3 位作者 Rawan Bossly Fuad SAlduais Afrah Al-Bossly Arshad Khan 《Chinese Physics B》 2025年第6期357-375,共19页
This work investigates water-based micropolar hybrid nanofluid(MHNF) flow on an elongating variable porous sheet.Nanoparticles of diamond and copper have been used in the water to boost its thermal conductivity. The m... This work investigates water-based micropolar hybrid nanofluid(MHNF) flow on an elongating variable porous sheet.Nanoparticles of diamond and copper have been used in the water to boost its thermal conductivity. The motion of the fluid is taken as two-dimensional with the impact of a magnetic field in the normal direction. The variable, permeable, and stretching nature of sheet's surface sets the fluid into motion. Thermal and mass diffusions are controlled through the use of the Cattaneo–Christov flux model. A dataset is generated using MATLAB bvp4c package solver and employed to train an artificial neural network(ANN) based on the Levenberg–Marquardt back-propagation(LMBP) algorithm. It has been observed as an outcome of this study that the modeled problem achieves peak performance at epochs 637, 112, 4848, and 344 using ANN-LMBP. The linear velocity of the fluid weakens with progression in variable porous and magnetic factors.With an augmentation in magnetic factor, the micro-rotational velocity profiles are augmented on the domain 0 ≤ η < 1.5 due to the support of micro-rotations by Lorentz forces close to the sheet's surface, while they are suppressed on the domain 1.5 ≤ η < 6.0 due to opposing micro-rotations away from the sheet's surface. Thermal distributions are augmented with an upsurge in thermophoresis, Brownian motion, magnetic, and radiation factors, while they are suppressed with an upsurge in thermal relaxation parameter. Concentration profiles increase with an expansion in thermophoresis factor and are suppressed with an intensification of Brownian motion factor and solute relaxation factor. The absolute errors(AEs) are evaluated for all the four scenarios that fall within the range 10^(-3)–10^(-8) and are associated with the corresponding ANN configuration that demonstrates a fine degree of accuracy. 展开更多
关键词 MHD fluid hybrid nanofluid Cattaneo–Christov flux model variable porous surface micropolar fluid brownian motion and thermophoresis ANN approach
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A Variable Separation Approach to Solve the Integrable and Nonintegrable Models:Coherent Structures of the (2 + 1)-Dimensional KdV Eqnation 被引量:8
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作者 TANG Xiao-Yan LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第7期1-8,共8页
We study the localized coherent structures ofa generally nonintegrable (2+ 1 )-dimensional KdV equation via a variable separation approach. In a special integrable case, the entrance of some arbitrary functions leads ... We study the localized coherent structures ofa generally nonintegrable (2+ 1 )-dimensional KdV equation via a variable separation approach. In a special integrable case, the entrance of some arbitrary functions leads to abundant coherent structures. However, in the general nonintegrable case, an additional condition has to be introduced for these arbitrary functions. Although the additional condition has been introduced into the solutions of the nonintegrable KdV equation, there still exist many interesting solitary wave structures. Especially, the nonintegrable KdV equation possesses the breather-like localized excitations, and the similar static ring soliton solutions as in the integrable case. Furthermor,in the integrable case, the interaction between two travelling ring solitons is elastic, while in the nonintegrable case we cannot find even the single travelling ring soliton solution. 展开更多
关键词 variable SEPARATION approach INTEGRABLE and nonintegrable models (2+1)-dimensional SOLITONS
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Synthetic security assessment based on variable consistency dominance-based rough set approach 被引量:3
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作者 赵亮 Xue Zhi 《High Technology Letters》 EI CAS 2010年第4期413-421,共9页
Security assessment can help understand the security conditions of an information system and yield results highly conducive to the solution of security problems in it. Taking the computer networks in a certain univers... Security assessment can help understand the security conditions of an information system and yield results highly conducive to the solution of security problems in it. Taking the computer networks in a certain university as samples, this paper, with the information system security assessment model as its foundation, proposes a multi-attribute group decision-making (MAGDM) security assessment method based on a variable consistency dominance-based rough set approach (VC-DRSA). This assessment method combines VC-DRSA with the analytic hierarchy process (AHP), uncovers the inherent information hidden in data via the quality of sorting (QoS), and makes a synthetic security assessment of the information system after determining the security attribute weight. The sample findings show that this method can effectively remove the bottleneck of MAGDM, thus assuming practical significance in information system security assessment. 展开更多
关键词 multi-attribute group decision-making (MAGDM) security assessment variable consistency dominance-based rough set approach (VC-DRSA)
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General Symmetry Approach to Solve Variable—Coefficient Nonlinear Equations 被引量:1
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作者 RUANHang-Yu CHENYi-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第6期641-646,共6页
After considering the variable coefficient of a nonlinear equation as a new dependent variable, some special types of variable-coefficient equation can be solved from the corresponding constant-coefficient equations b... After considering the variable coefficient of a nonlinear equation as a new dependent variable, some special types of variable-coefficient equation can be solved from the corresponding constant-coefficient equations by using the general classical Lie approach. Taking the nonlinear Schr?dinger equation as a concrete example, the method is recommended in detail. 展开更多
关键词 symmetry approach variable coefficient equation
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Multi-linear Variable Separation Approach to Solve a (2+1)-DimensionalGeneralization of Nonlinear Schroedinger System 被引量:1
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作者 SHENShou-Feng ZHANGJun PANZu-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6期965-968,共4页
By using a Baecklund transformation and the multi-linear variable separationapproach, we find a new general solution of a (2+1)-dimensional generalization of the nonlinearSchroedinger system. The new 'universal... By using a Baecklund transformation and the multi-linear variable separationapproach, we find a new general solution of a (2+1)-dimensional generalization of the nonlinearSchroedinger system. The new 'universal' formula is defined, and then, rich coherent structures canbe found by selecting corresponding functions appropriately. 展开更多
关键词 variable separation approach (2+1)-dimensional generalization of nonlinearschrodinger system coherent structure
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Energy Stable BDF2-SAV Scheme on Variable Grids for the Epitaxial Thin Film Growth Models
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作者 LI Juan 《Wuhan University Journal of Natural Sciences》 CSCD 2024年第6期517-522,共6页
The second-order backward differential formula(BDF2)and the scalar auxiliary variable(SAV)approach are applied to con‐struct the linearly energy stable numerical scheme with the variable time steps for the epitaxial ... The second-order backward differential formula(BDF2)and the scalar auxiliary variable(SAV)approach are applied to con‐struct the linearly energy stable numerical scheme with the variable time steps for the epitaxial thin film growth models.Under the stepratio condition 0<τ_(n)/τ_(n-1)<4.864,the modified energy dissipation law is proven at the discrete levels with regardless of time step size.Nu‐merical experiments are presented to demonstrate the accuracy and efficiency of the proposed numerical scheme. 展开更多
关键词 epitaxial thin film growth model variable-step second-order backward differential formula(BDF2)scheme scalar auxiliary variable(sav)approach unconditional energy stability
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Variable Separation Approach to Solve (2 + 1)-Dimensional Generalized Burgers System: Solitary Wave and Jacobi Periodic Wave Excitations
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作者 ZHENGChun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期391-396,共6页
By means of the standard truncated Painlevé expansion and a variable separation approach, a general variable separation solution of the generalized Burgers system is derived. In addition to the usual localized co... By means of the standard truncated Painlevé expansion and a variable separation approach, a general variable separation solution of the generalized Burgers system is derived. In addition to the usual localized coherent soliton excitations like dromions, lumps, rings, breathers, instantons, oscillating soliton excitations, peakons, foldons, and previously revealed chaotic and fractal localized solutions, some new types of excitations — compacton and Jacobi periodic wave solutions are obtained by introducing appropriate lower dimensional piecewise smooth functions and Jacobi elliptic functions. 展开更多
关键词 generalized Burgers system variable separation approach solitary wave Jacobi periodic wave
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Variable Separation Approach to Solve a (2+1)-Dimensional Integrable System
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作者 SHENShou-Feng PANZu-Liang ZHANGJun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期497-498,共2页
In this letter, starting from a B?cklund transformation, a general solution of a (2+1)-dimensional integrable system is obtained by using the new variable separation approach.
关键词 variable separation approach (2+1)-dimensional integrable system localized coherent structure
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Multi-linear Variable Separation Approach to Solve a (1+1)-Dimensional Coupled Integrable Dispersionless System
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作者 SHEN Shou-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期779-782,共4页
The multi-linear variable separation approach (MLVSA ) is very useful to solve (2+ 1)-dimensional integrable systems. In this letter, we extend this method to solve a (1+1)-dimensional coupled integrable dispersion-le... The multi-linear variable separation approach (MLVSA ) is very useful to solve (2+ 1)-dimensional integrable systems. In this letter, we extend this method to solve a (1+1)-dimensional coupled integrable dispersion-less system.Namely, by using a Backlund transformation and the MLVSA, we find a new general solution and define a new "universal formula". Then, some new (1+1)-dimensional coherent structures of this universal formula can be found by selecting corresponding functions appropriately. Specially, in some conditions, bell soliton and kink soliton can transform each other, which are illustrated graphically. 展开更多
关键词 variable separation approach (1+1)-dimensional coupled integrable dispersion-less system co-erent structure
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Notes on Multi-linear Variable Separation Approach
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作者 SHENShou-Feng ZHANGJun PANZu-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期582-584,共3页
The multi-linear variable separation approach method is very useful to solve (2+1)-dimensional integrable systems. In this letter, we extend this method to solve (1+1)-dimensional Boiti system, (2+1)-dimensional Burge... The multi-linear variable separation approach method is very useful to solve (2+1)-dimensional integrable systems. In this letter, we extend this method to solve (1+1)-dimensional Boiti system, (2+1)-dimensional Burgers system, (2+1)-dimensional breaking soliton system, and (2+1)-dimensional Maccari system. Some new exact solutions are obtained and the universal formula obtained from many (2+1)-dimensional systems is extended or modified. 展开更多
关键词 variable separation approach (1+1)-dimensional Boiti system (2+1)-dimensional Burgers system (2+1)-dimensional breaking soliton system (2+1) -dimensional Maccari system
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Micro-mechanical damage simulation of 2.5D woven variable thickness composites
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作者 Nan WANG Haitao CUI +3 位作者 Hongjian ZHANG Yaoming FU Gangjin HUANG Shuangqi LYU 《Chinese Journal of Aeronautics》 2025年第7期168-184,共17页
With the application of 2.5D Woven Variable Thickness Composites(2.5DWVTC)in aviation and other fields,the issue of strength failure in this composite type has become a focal point.First,a three-step modeling approach... With the application of 2.5D Woven Variable Thickness Composites(2.5DWVTC)in aviation and other fields,the issue of strength failure in this composite type has become a focal point.First,a three-step modeling approach is proposed to rapidly construct full-scale meso-finite element models for Outer Reduction Yarn Woven Composites(ORYWC)and Inner Reduction Yarn Woven Composites(IRYWC).Then,six independent damage variables are identified:yarn fiber tension/compression,yarn matrix tension/compression,and resin matrix tension/compression.These variables are utilized to establish the constitutive equation of woven composites,considering the coupling effects of microscopic damage.Finally,combined with the Hashin failure criterion and von Mises failure criterion,the strength prediction model is implemented in ANSYS using APDL language to simulate the strength failure process of 2.5DWVTC.The results show that the predicted stiffness and strength values of various parts of ORYWC and IRYWC are in good agreement with the relevant test results. 展开更多
关键词 Constitutive equation 2.5D woven variable thickness composites Damage variables Finite element models Modeling approach Strength prediction model
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MODIFIED SCHEME BASED ON SEMI-ANALYTIC APPROACH FOR COMPUTING NON-PROBABILISTIC RELIABILITY INDEX 被引量:5
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作者 Xuyong Chen Chak-yin Tang +1 位作者 Chi-pong Tsui Jianping Fan 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第2期115-123,共9页
A new computation scheme proposed to tackle commensurate problems is devel- oped by modifying the semi-analytic approach for minimizing computational complexity. Using the proposed scheme, the limit state equations, u... A new computation scheme proposed to tackle commensurate problems is devel- oped by modifying the semi-analytic approach for minimizing computational complexity. Using the proposed scheme, the limit state equations, usually referred to as the failure surface, are obtained from transformation of an interval variable to a normalized one. In order to minimize the computational cost, two algorithms for optimizing the calculation steps have been proposed. The monotonicity of the objective function can be determined from narrowing the scope of interval variables in normalized infinite space by incorporating the algorithms into the computational scheme. Two examples are used to illustrate the operation and computational efficiency of the approach. The results of these examples show that the proposed algorithms can greatly reduce the computation complexity without sacrificing the computational accuracy. The advantage of the proposed scheme can be even more efficient for analyzing sophistic structures. 展开更多
关键词 semi-analytic approach non-probabilistic reliability index interval variable state equation MONOTONICITY
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Novel model of thermo-magneto-viscoelastic medium with variable thermal conductivity under effect of gravity 被引量:1
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作者 S.M.SAID 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第5期819-832,共14页
The basic equations for a homogeneous and isotropic thermo-magnetoviscoelastic medium are formulated based on three different theories, i.e., the GreenLindsay(G-L) theory, the coupled(CD) theory, and the Lord-Shulman(... The basic equations for a homogeneous and isotropic thermo-magnetoviscoelastic medium are formulated based on three different theories, i.e., the GreenLindsay(G-L) theory, the coupled(CD) theory, and the Lord-Shulman(L-S) theory. The variable thermal conductivity is considered as a linear function of the temperature. Using suitable non-dimensional variables, these basic equations are solved via the eigenvalue approach. The medium is initially assumed to be stress-free and subject to a thermal shock.The numerical results reveal that the viscosity, the two-temperature parameter, the gravity term, and the magnetic field significantly influence the distribution of the physical quantities of the thermoelastic medium. 展开更多
关键词 eigenvalue approach variable thermal conductivity thermo-viscoelastic gravity field
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Simplification approaches for multi-level load spectra by using equivalent damage rule 被引量:1
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作者 Xiaohong LI Qin SUN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第11期119-130,共12页
Reasonable and effective fatigue load spectrum is key of aircraft structural fatigue test.Two kinds of load spectra simplification approaches based on statistical consistent fatigue damage model are proposed in the pa... Reasonable and effective fatigue load spectrum is key of aircraft structural fatigue test.Two kinds of load spectra simplification approaches based on statistical consistent fatigue damage model are proposed in the paper.One method is to simplify the original multi-level load spectra to spectral load with fewer level and was verified by the experimental data of five levels and seven levels load spectra.The equivalent damage here is not equivalent fatigue life,but equivalent number of spectral blocks.Moreover,it was proved that a section of low stress load cannot be converted into the highest stress load considering equivalent damage.The other is to convert the life distribution under multi-level load spectra into that of constant amplitude spectrum according to a certain principle,that is,equivalent damage is achieved through equivalent fatigue life,and two groups of three levels spectral data were used for experimental verification.The results show that equivalent damage simplification approach of multi-level load spectra is feasible,and it achieve that the damage of one loading block before and after the simplification is equal in probability statistics.The life distribution of load simplified as constant amplitude spectrum is consistent with test data.The simplification method presented in this paper can be generalized and is a predictive engineering method which does not depend on experimental data. 展开更多
关键词 Aircraft structure Equivalent fatigue life One loading block Simplification approaches variable amplitude loadings
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Spatio-Temporal Pulsating Dissipative Solitons through Collective Variable Methods 被引量:2
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作者 Olivier Asseu Ambroise Diby +1 位作者 Pamela Yoboué Aladji Kamagaté 《Journal of Applied Mathematics and Physics》 2016年第6期1032-1041,共10页
A semi-analytical approach for the pulsating solutions of the 3D complex Cubic-quintic Ginzburg-Landau Equation (CGLE) is presented in this article. A collective variable approach is used to obtain a system of variati... A semi-analytical approach for the pulsating solutions of the 3D complex Cubic-quintic Ginzburg-Landau Equation (CGLE) is presented in this article. A collective variable approach is used to obtain a system of variational equations which give the evolution of the light pulses parameters as a function of the propagation distance. The collective coordinate approach is incomparably faster than the direct numerical simulation of the propagation equation. This allows us to obtain, efficiently, a global mapping of the 3D pulsating soliton. In addition it allows describing the influence of the parameters of the equation on the various physical parameters of the pulse and their dynamics. 展开更多
关键词 Dissipative Soliton Pulsating Light Pulse Spatiotemporal Pulses Collective variable approach Complex Cubic-Quintic Ginzburg-Landau Equation BIFURCATION
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Non-Traveling Wave Solutions for the (1 + 1)-Dimensional Burgers System by Riccati Equation Mapping Approach
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作者 Ruiyang Xu Songhua Ma 《Applied Mathematics》 2013年第10期123-125,共3页
Starting from the symbolic computation system Maple and Riccati equation mapping approach and a linear variable separation approach, a new family of non-traveling wave solutions of the (1 + 1)-dimensional Burgers syst... Starting from the symbolic computation system Maple and Riccati equation mapping approach and a linear variable separation approach, a new family of non-traveling wave solutions of the (1 + 1)-dimensional Burgers system is derived. 展开更多
关键词 RICCATI Equation MAPPING approach Linear variable Separation approach BURGERS SYSTEM Non-Traveling Wave Solutions
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Variable separation solutions and new solitary wave structures to the (l+l)-dimensional Ito system
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作者 徐昌智 何宝钢 张解放 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期1-7,共7页
A variable separation approach is proposed and extended to the (1+1)-dimensional physics system. The variable separation solution of (1-F1)-dimensional Ito system is obtained. Some special types of solutions such... A variable separation approach is proposed and extended to the (1+1)-dimensional physics system. The variable separation solution of (1-F1)-dimensional Ito system is obtained. Some special types of solutions such as non-propagating solitary wave solution, propagating solitary wave solution and looped soliton solution are found by selecting the arbitrary function appropriately. 展开更多
关键词 (1+1)-dimensional Ito system variable separation approach new solitary wave structures
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Variable Separated Solutions and Four-Dromion Excitations for (2+1)-Dimensional Nizhnik-Novikov-Veselov Equation
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作者 HU Ya-Hong MA Zheng-Yi ZHENG Chun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期679-684,共6页
Using the mapping approach via the projective Riccati equations, several types of variable separated solutions of the (2+1)-dimensional Nizhnik-Novikov-Veselov equation are obtained, including multiple-soliton solu... Using the mapping approach via the projective Riccati equations, several types of variable separated solutions of the (2+1)-dimensional Nizhnik-Novikov-Veselov equation are obtained, including multiple-soliton solutions, periodic-soliton solutions, and Weierstrass function solutions. Based on a periodic-soliton solution, a new type of localized excitation, i.e., the four-dromion soliton, is constructed and some evolutional properties of this localized structure are briefly discussed. 展开更多
关键词 Imapping approach Nizhnik-Novikov-Veselov equation variable separated solution DROMION
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Efficient Approach for 3D Stationary Optical Solitons in Dissipative Systems
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作者 A. Konaté E. Soro +2 位作者 O. Asseu A. Kamagaté P. Yoboué 《Journal of Applied Mathematics and Physics》 2015年第10期1239-1248,共10页
We feature the stationary solutions of the 3D complex cubic-quintic Ginzburg-Landau equation (CGLE). Our approach is based on collective variables approach which helps to obtain a system of variational equations, givi... We feature the stationary solutions of the 3D complex cubic-quintic Ginzburg-Landau equation (CGLE). Our approach is based on collective variables approach which helps to obtain a system of variational equations, giving the evolution of the light pulses parameters as a function of the propagation distance. The collective variables approach permits us to obtain, efficiently, a global mapping of the 3D stationary dissipative solitons. In addition it allows describing the influence of the parameters of the equation on the various physical parameters of the pulse and their dynamics. Thus it helps to show the impact of dispersion and nonlinear gain on the stationary dynamic. 展开更多
关键词 DISSIPATIVE SOLITONS Dispersion Nonlinear Gain COLLECTIVE variables approach Complex Cubic-Quintic GINZBURG-LANDAU Equation (3D) Three-Dimensional SOLITON Spatio-Temporal Pulses
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A Series of Variable Separation Solutions and New Soliton Structures of (2+1)-Dimensional Korteweg-de Vries Equation
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作者 XU Chang-Zhi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3X期403-406,共4页
Variable separation approach is introduced to solve the (2+1)-dimensional KdV equation. A series of variable separation solutions is derived with arbitrary functions in system. We present a new soliton excitation m... Variable separation approach is introduced to solve the (2+1)-dimensional KdV equation. A series of variable separation solutions is derived with arbitrary functions in system. We present a new soliton excitation model (24). Based on this excitation, new soliton structures such as the multi-lump soliton and periodic soliton are revealed by selecting the arbitrary function appropriately. 展开更多
关键词 variable separation approach (2+1)-dimensional KdV equation new soliton excitation
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