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Approximate Generalized Conditional Symmetries for Perturbed Evolution Equations 被引量:3
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作者 ZHANG Shun-Li WANG Yong LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期975-980,共6页
The concept of approximate generalized conditional symmetry (AGCS) for the perturbed evolution equations is introduced, and how to derive approximate conditional invariant solutions to the perturbed equations via th... The concept of approximate generalized conditional symmetry (AGCS) for the perturbed evolution equations is introduced, and how to derive approximate conditional invariant solutions to the perturbed equations via their A GCSs is illustrated with examples. 展开更多
关键词 perturbed evolution equation approximate generalized conditional symmetry approximate con ditional invariant solution
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Approximate homotopy similarity reduction for the generalized Kawahara equation via Lie symmetry method and direct method 被引量:1
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作者 刘希忠 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期28-34,共7页
This paper studies the generalized Kawahara equation in terms of the approximate homotopy symmetry method and the approximate homotopy direct method. Using both methods it obtains the similarity reduction solutions an... This paper studies the generalized Kawahara equation in terms of the approximate homotopy symmetry method and the approximate homotopy direct method. Using both methods it obtains the similarity reduction solutions and similarity reduction equations of different orders, showing that the approximate homotopy direct method yields more general approximate similarity reductions than the approximate homotopy symmetry method. The homotopy series solutions to the generalized Kawahara equation are consequently derived. 展开更多
关键词 approximate homotopy symmetry method approximate homotopy direct method generalized Kawahara equation homotopy series solutions
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The scattering states of the generalized Hulthén potential with an improved new approximate scheme for the centrifugal term 被引量:1
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作者 卫高峰 陈文利 +1 位作者 王红英 李院院 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3663-3669,共7页
This paper finds the approximate analytical scattering state solutions of the arbitrary 1-wave Schrodinger equation for the generalized Hulthen potential by taking an improved new approximate scheme for the centrifuga... This paper finds the approximate analytical scattering state solutions of the arbitrary 1-wave Schrodinger equation for the generalized Hulthen potential by taking an improved new approximate scheme for the centrifugal term. The normalized analytical radial wave functions of the 1-wave SchrSdinger equation for the generalized Hulthen potential are presented and the corresponding calculation formula of phase shifts is derived. Some useful figures are plotted to show the improved accuracy of the obtained results and two special cases for the standard Hulthen potential and Woods-Saxon potential are also studied briefly. 展开更多
关键词 generalized Hulthen potential scattering states approximate analytical solutions
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GENERALIZED RAY APPROXIMATE METHOD TO INVERSE MEDIUM PARAMETERS
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作者 Niu, YQ Du, DS +1 位作者 Ma, XG Huang, WH 《Acta Mechanica Solida Sinica》 SCIE EI 1996年第1期59-65,共7页
In this paper, the inverse problem of the medium parameters in an inhomogeneous medium is studied and a generalized ray approximate form of the total wave field is described. First, the acoustic wave equation derived ... In this paper, the inverse problem of the medium parameters in an inhomogeneous medium is studied and a generalized ray approximate form of the total wave field is described. First, the acoustic wave equation derived from the elastic wave equation is studied, the referential variables and perturbational variables are introduced, and the integral equation of the medium perturbational parameters is obtained. Then from the point of view of the local principles of the wave function in an inhomogeneous medium, a generalized ray approximate form of the total wave field in an inhomogeneous medium is described, and attention is focused on the Fredholm integral equation of the first kind. Finally, the medium parameters in half-plane are inversed. Numerical examples show when the perturbations of the medium parameters are about 0.5, this method can effectively inverse its variation. Apparently, this method is better than the conventional Born weak scattering approximation. 展开更多
关键词 integral equation generalized ray approximation medium parameters function integral transform
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Approximate analytic solutions for a generalized Hirota—Satsuma coupled KdV equation and a coupled mKdV equation
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作者 赵国忠 蔚喜军 +2 位作者 徐云 朱江 吴迪 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期46-54,共9页
This paper applies the variational iteration method to obtain approximate analytic solutions of a generalized Hirota-Satsuma coupled Korteweg-de Vries (KdV) equation and a coupled modified Korteweg-de Vries (mKdV)... This paper applies the variational iteration method to obtain approximate analytic solutions of a generalized Hirota-Satsuma coupled Korteweg-de Vries (KdV) equation and a coupled modified Korteweg-de Vries (mKdV) equation. This method provides a sequence Of functions which converges to the exact solution of the problem and is based on the use of Lagrange multiplier for identification of optimal values of parameters in a functional. Some examples are given to demonstrate the reliability and convenience of the method and comparisons are made with the exact solutions. 展开更多
关键词 approximate analytic solutions generalized Hirota-Satsuma coupled KdV equation coupled mKdV equation variational iteration method
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EPSILON-ALGORITHM AND ETA-ALGORITHM OF GENERALIZED INVERSE FUNCTION-VALUED PAD APPROXIMANTS USING FOR SOLUTION OF INTEGRAL EQUATIONS 被引量:1
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作者 李春景 顾传青 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第2期221-229,共9页
Two efficient recursive algorithms epsilon_algorithm and eta_algorithm are introduced to compute the generalized inverse function_valued Padé approximants. The approximants were used to accelerate the convergenc... Two efficient recursive algorithms epsilon_algorithm and eta_algorithm are introduced to compute the generalized inverse function_valued Padé approximants. The approximants were used to accelerate the convergence of the power series with function_valued coefficients and to estimate characteristic value of the integral equations. Famous Wynn identities of the Pad approximants is also established by means of the connection of two algorithms. 展开更多
关键词 generalized inverse function_valued Padé approximant epsilon_algorithm eta_algorithm integral equations
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A generalized Padé approximation method of solving homoclinic and heteroclinic orbits of strongly nonlinear autonomous oscillators 被引量:1
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作者 李震波 唐驾时 蔡萍 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期78-84,共7页
An intrinsic extension of Pad′e approximation method, called the generalized Pad′e approximation method, is proposed based on the classic Pad′e approximation theorem. According to the proposed method, the numerator... An intrinsic extension of Pad′e approximation method, called the generalized Pad′e approximation method, is proposed based on the classic Pad′e approximation theorem. According to the proposed method, the numerator and denominator of Pad′e approximant are extended from polynomial functions to a series composed of any kind of function, which means that the generalized Pad′e approximant is not limited to some forms, but can be constructed in different forms in solving different problems. Thus, many existing modifications of Pad′e approximation method can be considered to be the special cases of the proposed method. For solving homoclinic and heteroclinic orbits of strongly nonlinear autonomous oscillators, two novel kinds of generalized Pad′e approximants are constructed. Then, some examples are given to show the validity of the present method. To show the accuracy of the method, all solutions obtained in this paper are compared with those of the Runge–Kutta method. 展开更多
关键词 generalized Pad′e approximation method homoclinic and heteroclinic orbits strongly nonlinear oscillators
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Degeneracy Cases of Generalized Inverse Function-Valued Padé Approximation 被引量:1
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作者 潘宝珍 顾传青 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期258-263,共6页
A new generalized inverse function-valued Padé approximation (GIFPA) was defined. Existence condition of GIFPA was given and its uniqueness theorem was proved. All possible degeneracy cases of GIFPA were discusse... A new generalized inverse function-valued Padé approximation (GIFPA) was defined. Existence condition of GIFPA was given and its uniqueness theorem was proved. All possible degeneracy cases of GIFPA were discussed and constructed. An example was given to illustrate its application. 展开更多
关键词 generalized inverse function-valued Padé approximation (GIFPA) degeneracy cases existence and uniqueness.
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Assignment of terahertz vibrational modes of L-glutamine using density functional theory within generalized-gradient approximation 被引量:6
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作者 张寒 张朝晖 +3 位作者 赵小燕 张天尧 燕芳 申江 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期211-218,共8页
The crystal structure of L-glutamine is stabilized by a three-dimensional network of intermolecular hydrogen bonds.We utilize plane-wave density functional theory lattice-dynamics calculations within the generalized-g... The crystal structure of L-glutamine is stabilized by a three-dimensional network of intermolecular hydrogen bonds.We utilize plane-wave density functional theory lattice-dynamics calculations within the generalized-gradient approximation(GGA), Perdew–Burke–Ernzerhof(PBE), PBE for solids(PBEsol), PBE with Wu–Cohen exchange(WC), and dispersion-corrected PBE, to investigate the effect of these intermolecular contacts on the absorption spectra of glutamine in the terahertz frequency range. Among these calculations, the solid-state simulated results obtained using the WC method exhibit a good agreement with the measured absorption spectra, and the absorption features are assigned with the help of WC. This indicates that the vibrational modes of glutamine were related to the combination of intramolecular and intermolecular motions, the intramolecular modes were dominated by rocking or torsion involving functional groups; the intermolecular modes mainly result from the translational motions of individual molecules, and the rocking of the hydrogenbonded functional groups. 展开更多
关键词 terahertz vibrational modes amino acid plane-wave density functional theory generalized-gradient approximation
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Some Algebraic Properties of Generalized Inverse Matrix-Valued Padé Approximation
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《Advances in Manufacturing》 SCIE CAS 2000年第4期275-278,共4页
关键词 MATH approximation PAD Some Algebraic Properties of generalized Inverse Matrix-Valued
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GENERALIZED SIMULTANEOUS CHEBYSHEV APPROXIMATION
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作者 罗祖华 《Analysis in Theory and Applications》 1992年第1期87-96,共10页
In this note,we develop,without assuming the Haar condition,a generalized simultaneous Chebyshev approximation theory which is similar to the classical Chebyshev theory and con- rains it as a special case.Our results ... In this note,we develop,without assuming the Haar condition,a generalized simultaneous Chebyshev approximation theory which is similar to the classical Chebyshev theory and con- rains it as a special case.Our results also contain those in[1]and[3]as a special case,and the two conjectures proposed by C.B.Dunham in[2]are proved to be true in the case of simulta- neous approximation. 展开更多
关键词 IIE generalized SIMULTANEOUS CHEBYSHEV approximATION
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A New Class of Generalized Landau Linear Positive Operator Sequence and Its Properties of Approximation
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作者 陈湛本 石济民 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第1期29-43, ,共15页
In this paper two sequences of generalized Landau linear positive operators are introduced. They can be applied in approximating continuous functions with arbitrary growth order, defined on a finite interval or the wh... In this paper two sequences of generalized Landau linear positive operators are introduced. They can be applied in approximating continuous functions with arbitrary growth order, defined on a finite interval or the whole real axis. The properties of approximation are studied and their asymptotic formulae are presented. These results show that their degrees of approximation are the best among existing operator sequences of Landau type, for example, their degrees of approximation for C 2[0, 1] are O(1/n 2) but corresponding degree of ordinary Landau operators are only O(1/n). 展开更多
关键词 generalized Landau linear positive operators degree of approximation asymptotic formula
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Electronic and Optical Properties of TiS2 Determined from Generalized Gradient Approximation Study
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作者 Hamza El-Kouch Larbi El Farh +1 位作者 Jamal Sayah Allal Challioui 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期96-99,共4页
The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient ... The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient approximation as proposed by Perdew et al. is used for the energy exchange-correlation determination. The results show a metallic character of TiS2, and the plots of total and partial densities of states of TiS2 show the metallic character of the bonds and a strong hybridization between the states d of Ti and p of S below the Fermi energy. The optical properties of the material such as real and imaginary parts of dielectric constant (ε(w) = ε1(w) + iε2(w)), refractive index n(w), optical reflectivity R(w), for E / /x and E / /z are performed for the energy range of 0-.14 eV. 展开更多
关键词 TI ab Electronic and Optical Properties of TiS2 Determined from generalized Gradient approximation Study
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APPROXIMATION OF CONTINUOUS FUNCTIONS BY GENERALIZED KARAMATA MEANS
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作者 S.A.SETTU 《Analysis in Theory and Applications》 1994年第1期88-98,共11页
A sufficient condition for the order of approximation of a continuous 2π periodic function with a given majorant for the modulus of continuity by the [F, d_n] means of its Fourier serier to be of Jackson order is obt... A sufficient condition for the order of approximation of a continuous 2π periodic function with a given majorant for the modulus of continuity by the [F, d_n] means of its Fourier serier to be of Jackson order is obtained. This sufficient condition is shown to be not enough for the order of approximation by partial sums of their Fourier series to be of Jackson order. The error estimate is shown to be the best possible. 展开更多
关键词 exp approximATION OF CONTINUOUS FUNCTIONS BY generalized KARAMATA MEANS
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Computation of waves scattered by inhomogeneous velocity gradient using generalized Born approximation
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作者 LIU Bo SUN Jianguo MENG Xiangyu 《Global Geology》 2020年第1期24-31,共8页
The generalized Born approximation is an approximation method that represents the scattering term by the error between the exact Green's function and the approximate Green's function,mainly for the gradient sc... The generalized Born approximation is an approximation method that represents the scattering term by the error between the exact Green's function and the approximate Green's function,mainly for the gradient scattering problem.However,so far,the research on the generalized Born approximation has only stayed in theory,and its implementation techniques are rarely reported.In order to fill this gap,the basic theory of generalized Born approximation is reviewed,and the implementation method of generalized Born approximation is discussed in this paper.In particular,the problem of calculating boundary effect elimination is discussed in detail.Finally,through model trial calculation,the calculation of gradient scattering,by comparing Born approximation and finite difference method,shows that using the generalized Born approximation to calculate gradient scattering achieves higher computational accuracy. 展开更多
关键词 generalized Born approximation gradient scattering implementation technology numerical simulation
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THE GENERALIZED REFLEXIVE SOLUTION FOR A CLASS OF MATRIX EQUATIONS (AX-B,XC=D) 被引量:7
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作者 李范良 胡锡炎 张磊 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期185-193,共9页
In this article, the generalized reflexive solution of matrix equations (AX = B, XC = D) is considered. With special properties of generalized reflexive matrices, the necessary and sufficient conditions for the solv... In this article, the generalized reflexive solution of matrix equations (AX = B, XC = D) is considered. With special properties of generalized reflexive matrices, the necessary and sufficient conditions for the solvability and the general expression of the solution are obtained. Moreover, the related optimal approximation problem to a given matrix over the solution set is solved. 展开更多
关键词 Matrix equations generalized reflexive matrix optimal approximation
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A NEW ITERATIVE METHOD FOR FINDING COMMON SOLUTIONS OF GENERALIZED EQUILIBRIUM PROBLEM,FIXED POINT PROBLEM OF INFINITE k-STRICT PSEUDO-CONTRACTIVE MAPPINGS,AND QUASI-VARIATIONAL INCLUSION PROBLEM 被引量:5
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作者 刘敏 张石生 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期499-519,共21页
In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseu... In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseudo-contractive mappings, and the set of solutions of the variational inclusion problem with multi-valued maximal monotone mappings and inverse-strongly monotone mappings in Hilbert space. Under suitable conditions, some strong convergence theorems are proved. Our results extends the recent results in G.L.Acedo and H.K.Xu [2], Zhang, Lee and Chan [8], Wakahashi and Toyoda [9], Takahashi and Takahashi [I0] and S. S. Chang, H. W. Joseph Lee and C. K. Chan [II], S.Takahashi and W.Takahashi [12]. Moreover, the method of proof adopted in this article is different from those of [4] and [12]. 展开更多
关键词 k-strict pseudo-contractive mappings generalized equilibrium problem vis-cosity approximation method variational inclusion problem multi-valuedmaximal monotone mappings s-inverse-strongly monotone mapping
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Using of the Generalized Special Relativity (GSR) in estimating the proton (nucleon) mass to explain the mass defect 被引量:4
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作者 Mahmoud Hamid Mahmoud Hilo M. D. Abd Allah Khalid Mohammed Haroon 《Natural Science》 2011年第2期141-144,共4页
This paper presents theoretical investigation on explanation of the mass defect estimating a new value for the proton mass inside the nucleus in the presence of the gravitational potential, the work has been done by u... This paper presents theoretical investigation on explanation of the mass defect estimating a new value for the proton mass inside the nucleus in the presence of the gravitational potential, the work has been done by using a new theory called the generalized special relativity (GSR). 展开更多
关键词 generalized MASS DEFECT GSR approximATIONS
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LEVITIN-POYAK WELL-POSEDNESS OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS WITH FUNCTIONAL CONSTRAINTS 被引量:2
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作者 王刚 黄学祥 +1 位作者 张杰 陈光亚 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1400-1412,共13页
In this article, we study Levitin-Polyak type well-posedness for generalized vector equilibrium problems with abstract and functional constraints. Criteria and characterizations for these types of well-posednesses are... In this article, we study Levitin-Polyak type well-posedness for generalized vector equilibrium problems with abstract and functional constraints. Criteria and characterizations for these types of well-posednesses are given. 展开更多
关键词 generalized vector equilibrium problems WELL-POSEDNESS set-valued map approximating solution sequence
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EXPONENTIALLY BOUNDED C-SEMIGROUP AND INTEGRATED SEMIGROUP WITH NONDENSELY DEFINED GENERATORS I: APPROXIMATION: 被引量:5
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作者 郑权 雷岩松 《Acta Mathematica Scientia》 SCIE CSCD 1993年第3期251-260,共10页
In this paper, by Laplace transform version of the Trotter-Kato approximation theorem and the integrated C-semigroup introduced by Myadera, the authors obtained some Trotter-Kato approximation theorems on exponentiall... In this paper, by Laplace transform version of the Trotter-Kato approximation theorem and the integrated C-semigroup introduced by Myadera, the authors obtained some Trotter-Kato approximation theorems on exponentially bounded C-semigroups, where the range of C (and so the domain of the generator) may not be dense. The authors deduced the corresponding results on exponentially bounded integrated semigroups with nondensely generators. The results of this paper extended and perfected the results given by Lizama, Park and Zheng. 展开更多
关键词 approximATION EXPONENTIALLY BOUNDED C-SEMIGROUP AND INTEGRATED SEMIGROUP WITH NONDENSELY DEFINED generATORS I
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