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THE SMOOTHING EFFECT IN SHARP GEVREY SPACE FOR THE SPATIALLY HOMOGENEOUS NON-CUTOFF BOLTZMANN EQUATIONS WITH A HARDPOTENTIAL
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作者 刘吕桥 曾娟 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期455-473,共19页
In this article, we study the smoothing effect of the Cauchy problem for the spatially homogeneous non-cutoff Boltzmann equation for hard potentials. It has long been suspected that the non-cutoff Boltzmann equation e... In this article, we study the smoothing effect of the Cauchy problem for the spatially homogeneous non-cutoff Boltzmann equation for hard potentials. It has long been suspected that the non-cutoff Boltzmann equation enjoys similar regularity properties as to whose of the fractional heat equation. We prove that any solution with mild regularity will become smooth in Gevrey class at positive time, with a sharp Gevrey index, depending on the angular singularity. Our proof relies on the elementary L^(2) weighted estimates. 展开更多
关键词 Boltzmann equation Gevrey regularity non-cutoff hard potential
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Multi-soliton solutions of coupled Lakshmanan-Porsezian-Daniel equations with variable coefficients under nonzero boundary conditions
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作者 赵会超 马雷诺 解西阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期137-152,共16页
This paper aims to investigate the multi-soliton solutions of the coupled Lakshmanan–Porsezian–Daniel equations with variable coefficients under nonzero boundary conditions.These equations are utilized to model the ... This paper aims to investigate the multi-soliton solutions of the coupled Lakshmanan–Porsezian–Daniel equations with variable coefficients under nonzero boundary conditions.These equations are utilized to model the phenomenon of nonlinear waves propagating simultaneously in non-uniform optical fibers.By analyzing the Lax pair and the Riemann–Hilbert problem,we aim to provide a comprehensive understanding of the dynamics and interactions of solitons of this system.Furthermore,we study the impacts of group velocity dispersion or the fourth-order dispersion on soliton behaviors.Through appropriate parameter selections,we observe various nonlinear phenomena,including the disappearance of solitons after interaction and their transformation into breather-like solitons,as well as the propagation of breathers with variable periodicity and interactions between solitons with variable periodicities. 展开更多
关键词 soliton Riemann-Hilbert problem non-zero boundary conditions coupled Lakshmanan-Porsezian-Daniel equation
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The Limit Distribution of Stochastic Evolution Equations Driven by-Stable Non-Gaussian Noise
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作者 ZHAI Likai FU Hongbo 《应用数学》 北大核心 2024年第4期1180-1194,共15页
We study the distribution limit of a class of stochastic evolution equation driven by an additive-stable Non-Gaussian process in the case of α∈(1,2).We prove that,under suitable conditions,the law of the solution co... We study the distribution limit of a class of stochastic evolution equation driven by an additive-stable Non-Gaussian process in the case of α∈(1,2).We prove that,under suitable conditions,the law of the solution converges weakly to the law of a stochastic evolution equation with an additive Gaussian process. 展开更多
关键词 Stochastic evolution equation α-stable Non-Gaussian process DISTRIBUTION
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New Lump Solution and Their Interactions with N-Solitons for a Shallow Water Wave Equation
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作者 Yin Ji Xiyu Tan 《Journal of Applied Mathematics and Physics》 2024年第8期2836-2848,共13页
By employing the Hirota’s bilinear method and different test functions, the breather solutions of HSI equation with different structures are obtained based on symbolic calculation with perturbation parameters. Some n... By employing the Hirota’s bilinear method and different test functions, the breather solutions of HSI equation with different structures are obtained based on symbolic calculation with perturbation parameters. Some new lump solitons are found in the process of studying the degradation behavior of breather solutions. The interaction between lump solution and soliton solution is constructed in the form of lump solution, and the motion trajectory of lump is obtained. In addition, the theorem of lump solitons and N-solitons superposition is given and proved. The superposition formula of lump is derived from the theorem, and its spatial evolution behavior is given. 展开更多
关键词 HSI equation Breather-Waves Lump Solutions Interaction Solution
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Fresnel Equations Derived Using a Non-Local Hidden-Variable Particle Theory
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作者 Dirk J. Pons 《Journal of Modern Physics》 2024年第6期950-984,共35页
Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel... Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel equations appear not to exist. Approach: The objective of this work was to derive the basic optical laws from first principles from a particle basis. The particle model used was the Cordus theory, a type of non-local hidden-variable (NLHV) theory that predicts specific substructures to the photon and other particles. Findings: The theory explains the origin of the orthogonal electrostatic and magnetic fields, and re-derives the refraction and reflection laws including Snell’s law and critical angle, and the Fresnel equations for s and p-polarisation. These formulations are identical to those produced by electromagnetic wave theory. Contribution: The work provides a comprehensive derivation and physical explanation of the basic optical laws, which appears not to have previously been shown from a particle basis. Implications: The primary implications are for suggesting routes for the theoretical advancement of fundamental physics. The Cordus NLHV particle theory explains optical phenomena, yet it also explains other physical phenomena including some otherwise only accessible through quantum mechanics (such as the electron spin g-factor) and general relativity (including the Lorentz and relativistic Doppler). It also provides solutions for phenomena of unknown causation, such as asymmetrical baryogenesis, unification of the interactions, and reasons for nuclide stability/instability. Consequently, the implication is that NLHV theories have the potential to represent a deeper physics that may underpin and unify quantum mechanics, general relativity, and wave theory. 展开更多
关键词 Wave-Particle Duality Optical Law Fresnel equation Non-Local Hidden-Variable
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Crank-Nicolson Quasi-Compact Scheme for the Nonlinear Two-Sided Spatial Fractional Advection-Diffusion Equations
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作者 Dechao Gao Zeshan Qiu +1 位作者 Lizan Wang Jianxin Li 《Journal of Applied Mathematics and Physics》 2024年第4期1089-1100,共12页
The higher-order numerical scheme of nonlinear advection-diffusion equations is studied in this article, where the space fractional derivatives are evaluated by using weighted and shifted Grünwald difference oper... The higher-order numerical scheme of nonlinear advection-diffusion equations is studied in this article, where the space fractional derivatives are evaluated by using weighted and shifted Grünwald difference operators and combining the compact technique, in the time direction is discretized by the Crank-Nicolson method. Through the energy method, the stability and convergence of the numerical scheme in the sense of L<sub>2</sub>-norm are proved, and the convergence order is . Some examples are given to show that our numerical scheme is effective. 展开更多
关键词 Crank-Nicolson Quasi-Compact Scheme Fractional Advection-Diffusion equations NONLINEAR Stability and Convergence
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Thermomechanical Dynamics (TMD) and Bifurcation-Integration Solutions in Nonlinear Differential Equations with Time-Dependent Coefficients
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2024年第5期1733-1743,共11页
The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple ba... The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple back-and-forth motion develops into water drinking motion. The solution to a drinking bird equation of motion manifests itself the transition from thermodynamic equilibrium to nonequilibrium irreversible states. The independent solution signifying a nonequilibrium thermal state seems to be constructed as if two independent bifurcation solutions are synthesized, and so, the solution is tentatively termed as the bifurcation-integration solution. The bifurcation-integration solution expresses the transition from mechanical and thermodynamic equilibrium to a nonequilibrium irreversible state, which is explicitly shown by the nonlinear differential equation with time-dependent coefficients (NDE-TC). The analysis established a new theoretical approach to nonequilibrium irreversible states, thermomechanical dynamics (TMD). The TMD method enables one to obtain thermodynamically consistent and time-dependent progresses of thermodynamic quantities, by employing the bifurcation-integration solutions of NDE-TC. We hope that the basic properties of bifurcation-integration solutions will be studied and investigated further in mathematics, physics, chemistry and nonlinear sciences in general. 展开更多
关键词 The Nonlinear Differential equation with Time-Dependent Coefficients The Bifurcation-Integration Solution Nonequilibrium Irreversible States Thermomechanical Dynamics (TMD)
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EXISTENCE AND UNIQUENESS OF SOLUTIONS FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS WITH NON-SEPARATED TYPE INTEGRAL BOUNDARY CONDITIONS 被引量:6
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作者 Bashir Ahmad Juan J. Nieto Ahmed Alsaedi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2122-2130,共9页
In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results a... In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-Schauder degree theory. Some illustrative examples are also presented. We extend previous results even in the integer case q = 2. 展开更多
关键词 fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem LeraySchauder degree
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Multisymplectic implicit and explicit methods for Klein-Gordon-Schrdinger equations 被引量:1
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作者 蔡加祥 杨斌 梁华 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期99-105,共7页
We propose multisymplectic implicit and explicit Fourier pseudospectral methods for the Klein-Gordon-Schrodinger equations.We prove that the implicit method satisfies the charge conservation law exactly.Both methods p... We propose multisymplectic implicit and explicit Fourier pseudospectral methods for the Klein-Gordon-Schrodinger equations.We prove that the implicit method satisfies the charge conservation law exactly.Both methods provide accurate solutions in long-time computations and simulate the soliton collision well.The numerical results show the abilities of the two methods in preserving the charge,energy,and momentum conservation laws. 展开更多
关键词 Klein-Gordon-schrodinger equations multisymplectic method Fourier pseudospectral method conservation law
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SERIES PERTURBATIONS APPROXIMATE SOLUTIONS TO N-S EQUATIONS AND MODIFICATION TO ASYMPTOTIC EXPANSION MATCHED METHOD
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作者 李大鸣 张红萍 高永祥 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第8期963-972,共10页
A method that series perturbations approximate solutions to N-S equations with boundary conditions was discussed and adopted. Then the method was proved in which the asymptotic solutions of viscous fluid flow past a s... A method that series perturbations approximate solutions to N-S equations with boundary conditions was discussed and adopted. Then the method was proved in which the asymptotic solutions of viscous fluid flow past a sphere were deducted. By the ameliorative asymptotic expansion matched method, the matched functions, are determined easily and the ameliorative curve of drag coefficient is coincident well with measured data in the case that Reynolds number is less than or equal to 40 000. 展开更多
关键词 asymptotic expansion matched method series perturbation n-s equation viscous fluid flow past a sphere
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Exact solutions for the coupled Klein-Gordon-Schrǒdinger equations using the extended F-expansion method 被引量:1
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作者 何红生 陈江 杨孔庆 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第10期1926-1931,共6页
The extended F-expansion method or mapping method is used to construct exact solutions for the coupled KleinGordon Schr/Sdinger equations (K-G-S equations) by the aid of the symbolic computation system Mathematica. ... The extended F-expansion method or mapping method is used to construct exact solutions for the coupled KleinGordon Schr/Sdinger equations (K-G-S equations) by the aid of the symbolic computation system Mathematica. More solutions in the Jacobi elliptic function form are obtained, including the single Jacobi elliptic function solutions, combined Jacobi elliptic function solutions, rational solutions, triangular solutions, soliton solutions and combined soliton solutions. 展开更多
关键词 extended F-expansion method exact solutions coupled K-G-S equations Jacobi elliptic function
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A NOTE ON NONAUTONOMOUS KLEIN-GORDON-SCHRDINGER EQUATIONS WITH HOMOGENEOUS DIRICHLET BOUNDARY CONDITION 被引量:1
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作者 赵才地 周盛凡 李用声 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期823-833,共11页
This note discusses the long time behavior of solutions for nonautonomous weakly dissipative Klein-Gordon-Schrodinger equations with homogeneous Dirichlet boundary condition.The authors prove the existence of compact ... This note discusses the long time behavior of solutions for nonautonomous weakly dissipative Klein-Gordon-Schrodinger equations with homogeneous Dirichlet boundary condition.The authors prove the existence of compact kernel sections for the associated process by using a suitable decomposition of the equations. 展开更多
关键词 Nonautonomous Klein-Gordon-schrSdinger equations kernel sections weakly dissipation uniformly asymptotic compactness
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Hamilton-Souplet-Zhang's gradient estimates for two weighted nonlinear parabolic equations 被引量:1
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作者 MA Bing-qing HUANG Guang-yue 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第3期353-364,共12页
In this paper, we consider gradient estimates for positive solutions to the following weighted nonlinear parabolic equations on a complete smooth metric measure space with only Bakry-Émery Ricci tensor bounded be... In this paper, we consider gradient estimates for positive solutions to the following weighted nonlinear parabolic equations on a complete smooth metric measure space with only Bakry-Émery Ricci tensor bounded below: One is $${u_t} = {\Delta _f}u + au\log u + bu$$ with a, b two real constants, and another is $${u_t} = {\Delta _f}u + \lambda {u^\alpha }$$ with λ, α two real constants. We obtain local Hamilton-Souplet-Zhang type gradient estimates for the above two nonlinear parabolic equations. In particular, our estimates do not depend on any assumption on f. 展开更多
关键词 Hamilton’s gradient estimate Souplet-Zhang’s gradient estimate weighted nonlinear parabolic equation Bakry-Émery Ricci tensor
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Gasser-Leutwyler Coefficients of Chiral Lagrangian for Pseudoscalar Goldstone Bosons in Dyson-Schwinger Equations 被引量:1
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作者 GU Yun-Ting QIN Song-Mei +1 位作者 ZHOU Li-Juan MA Wei-Xing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1205-1210,共6页
Based on the Dyson-Schwinger equations of quark propagator in rainbow truncation with an effective gluonpropagator,the ten unknown Gasser-Leutwyler coefficients of the chiral Lagrangian for pseudoscalar Goldstone boso... Based on the Dyson-Schwinger equations of quark propagator in rainbow truncation with an effective gluonpropagator,the ten unknown Gasser-Leutwyler coefficients of the chiral Lagrangian for pseudoscalar Goldstone bosonsare predicted.The predicted values of L_i with i=1,2,...,10 are in a reasonable agreement with empirical values usedwidely in literature,and the values predicted by many other theoretical models with QCD characteristics. 展开更多
关键词 chiral perturbation theory Gasser-Leutwyler coefficient Dyson-schwinger equation
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Extended F-Expansion Method and Periodic Wave Solutions for Klein-Gordon-SchrSdinger Equations 被引量:2
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作者 LI Xiao-Yan LI Xiang-Zheng WANG Ming-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期9-14,共6页
We present an extended F-expansion method for finding periodic wave solutions of nonlinear evolution equations in mathematical physics. By using extended F-expansion method, many periodic wave solutions expressed by v... We present an extended F-expansion method for finding periodic wave solutions of nonlinear evolution equations in mathematical physics. By using extended F-expansion method, many periodic wave solutions expressed by various Jacobi elliptic functions for the Klein-Gordon-Schrodinger equations are obtained. In the limit cases, the solitary wave solutions and trigonometric function solutions for the equations are also obtained. 展开更多
关键词 Klein-Gordon-schrodinger equations F-expansion method periodic wave solutions Jacobi elliptic functions solitary wave solutions
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A COLUMN-SECANT UPDATE TECHNIQUE FOR SOLVING SYSTEM OF NONLINEAR EQUATIONS
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作者 李光烨 刘停战 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第2期193-206,共14页
In this paper,we present a column-secant modification of the SCC method,which is called the CSSCC method.The CSSCC method uses function values more efficiently than the SCC method,and it is shown that the CSSCC method... In this paper,we present a column-secant modification of the SCC method,which is called the CSSCC method.The CSSCC method uses function values more efficiently than the SCC method,and it is shown that the CSSCC method has better local q-convergence and r-convergence rates than the SCC method.The numerical results show that the CSSCC method is competitive with some well known methods for some standard test problems. 展开更多
关键词 nonlinear equations JACOBIAN Newton’s method q-convergence
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Orbital Stability of Solitary Waves for Generalized Klein-Gordon-Schrodinger Equations
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作者 Wenhui Qi Guoguang Lin 《Applied Mathematics》 2011年第8期1005-1010,共6页
This paper concerns the orbital stability for exact solitary waves of the Generalized Klein-Gordon-Schrod-inger equations. Since the abstract results of Grillakis et al[1-2] can not be applied directly, we can extend ... This paper concerns the orbital stability for exact solitary waves of the Generalized Klein-Gordon-Schrod-inger equations. Since the abstract results of Grillakis et al[1-2] can not be applied directly, we can extend the abstract stability theory and use the detailed spectral analysis to obtain the stability of the solitary waves. 展开更多
关键词 SOLITARY WAVES Stability Klein-Gordon-schrodinger equations
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Simulation on Helicopter Scissors Tail-Rotor Noise Based on N-S Equations and F1A Formulas
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作者 Meng Xiaowei Xu Guohua +1 位作者 Shi Yongjie Wang Liangquan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期710-719,共10页
Aiming at the noise of helicopter scissors tail-rotor,an advanced numerical method is established by combining computational fluid dynamics(CFD)model with Farassat 1 A(F1 A)formula.In this method,Navier-tokes(N-S)equa... Aiming at the noise of helicopter scissors tail-rotor,an advanced numerical method is established by combining computational fluid dynamics(CFD)model with Farassat 1 A(F1 A)formula.In this method,Navier-tokes(N-S)equations are used as governing equations,and the flow field is solved at quasi-steady and unsteady states in hover and forward fight,respectively,based on two different types of embedded grid systems.A simple and effective solution approach is provided for the generation difficulty of donor cells caused by the close gap among scissors tail-rotor blades.Using the CFD calculation results as input,the thickness noise,loading noise and total noise of tail-rotor are calculated by F1 Aformula.By the method,numerical examples on rotor flowfield and noise are performed and the results are compared with available data.Then,aerodynamic and acoustic characteristics of scissors tail-rotor are emphatically calculated in both hover and forward flight.Furthermore,the research on the effects of blade-tip shape parameters on scissors tail-rotor noise is carried out.Also,the scissors tail-rotor is compared with the conventional tail-rotor,and the results show that in hover,the noise of a scissors tail-rotor is not always the smaller one. 展开更多
关键词 FW-H equation scissors tail rotor thickness noise loading noise HELICOPTER computational fluid dynamics(CFD)
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A STABILIZED CRANK-NICOLSON MIXED FINITE VOLUME ELEMENT FORMULATION FOR THE NON-STATIONARY PARABOLIZED NAVIER-STOKES EQUATIONS
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作者 罗振东 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1055-1066,共12页
A time semi-discrete Crank-Nicolson (CN) formulation with second-order time accuracy for the non-stationary parabolized Navier-Stokes equations is firstly established. And then, a fully discrete stabilized CN mixed ... A time semi-discrete Crank-Nicolson (CN) formulation with second-order time accuracy for the non-stationary parabolized Navier-Stokes equations is firstly established. And then, a fully discrete stabilized CN mixed finite volume element (SCNMFVE) formu- lation based on two local Gaussian integrals and parameter-free with the second-order time accuracy is established directly from the time semi-discrete CN formulation so that it could avoid the discussion for semi-discrete SCNMFVE formulation with respect to spatial wriables and its theoretical analysis becomes very simple. Finally, the error estimates of SCNMFVE solutions are provided. 展开更多
关键词 non-stationary parabolized Navier-Stokes equations stabilized Crank-Nicolson mixed finite volume element formulation error estimate
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A NOTE ON PROBABILISTIC CONTRACTOR COUPLE AND SOLUTIONS FOR A SYSTEM OF NONLINEAR EQUATIONS IN N A MENGER PN-SPACES
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作者 方锦暄 宋桂安 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第7期841-848,共8页
The concept of (Phi, Delta)-type probabilistic contractor couple was introduced which simplifies and weakens the definition of probabilistic contractor couple given by Zhang Shisheng. The existence and uniqueness of t... The concept of (Phi, Delta)-type probabilistic contractor couple was introduced which simplifies and weakens the definition of probabilistic contractor couple given by Zhang Shisheng. The existence and uniqueness of the solutions for a system of nonlinear operator equations with this kind of propabilistic contractor couple in N. A. Menger PN-spaces were studied. The works improve and extend the corresponding results by M. Altman, A. C. Lee, W. J. Padgett et al. 展开更多
关键词 N. A. Menger Pn-space (Phi Delta)-probabilistic contractor couple selective operator nonlinear operator equations
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