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三维稳态Q-tensor液晶流系统各向异性的Liouville型定理
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作者 胡立立 曹志杰 别群益 《应用数学》 北大核心 2024年第3期629-635,共7页
考虑速度分量的各向异性进行能量估计,得到三维稳态Q-tensor液晶流系统的Liouville型定理,即若u∈L^(q)(R^(3))∩˙H^(1)(R^(3)),u_(i)∈L xi q/q−2 L s xei(R×R^(2))(i=1,2,3),且Q∈H^(2)(R^(3)),其中2/q+1/s≥1/2,1≤s≤∞,2<... 考虑速度分量的各向异性进行能量估计,得到三维稳态Q-tensor液晶流系统的Liouville型定理,即若u∈L^(q)(R^(3))∩˙H^(1)(R^(3)),u_(i)∈L xi q/q−2 L s xei(R×R^(2))(i=1,2,3),且Q∈H^(2)(R^(3)),其中2/q+1/s≥1/2,1≤s≤∞,2<q<∞,则该稳态系统只有平凡解.这个结论推广了已有的结果. 展开更多
关键词 liouville型定理 液晶流 各向异性 Q-tensor
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R_(+)^(N)上不同阶椭圆方程组的Liouville型定理
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作者 赵围围 邵晓翎 +1 位作者 胡昌慧 程之羽 《应用数学》 北大核心 2024年第2期482-488,共7页
本文研究带Navier边值的不同阶椭圆方程组的Liouville型问题.主要结论的证明采用了伸缩变换,双边引理和积分形式的移动平面方法.
关键词 不同阶椭圆方程 liouville型定理 Navier边值
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含有Hénon项的非线性椭圆系统稳定解的Liouville定理
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作者 黄宇鑫 甘怡清 胡良根 《宁波大学学报(理工版)》 CAS 2024年第2期86-95,共10页
本文主要研究含有Hénon项的k-耦合椭圆系统-Δu_(i)=Σ_(j-1)^(k)β_(ij)|χ|^(α)|u_(i)|^(q-1)ui|uj|^(q+1),x∈R^(N)其中k是一个固定的正整数,i=1,2,…,k,q≥1,N≥3,B=(β_(ij))_(i,j=1)^(k)为实对称矩阵.首先使用Pohozaev恒等... 本文主要研究含有Hénon项的k-耦合椭圆系统-Δu_(i)=Σ_(j-1)^(k)β_(ij)|χ|^(α)|u_(i)|^(q-1)ui|uj|^(q+1),x∈R^(N)其中k是一个固定的正整数,i=1,2,…,k,q≥1,N≥3,B=(β_(ij))_(i,j=1)^(k)为实对称矩阵.首先使用Pohozaev恒等式构造单调公式,并发现其等价关系.当矩阵B严格余正时,联合使用Pohozaev恒等式、单调公式和爆缩序列方法证明了(无论是正的还是变号的)稳定解的Liouville定理. 展开更多
关键词 liouville定理 稳定解 POHOZAEV恒等式 单调公式 爆缩序列
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基于Riemann-Liouville分数阶积分Bernstein-Kantorovich算子的逼近性质
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作者 汪洋 程文韬 +1 位作者 刘玉洁 刘磊 《淮北师范大学学报(自然科学版)》 CAS 2024年第1期27-32,共6页
文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐... 文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐进公式。该算子的构建使得在曲线曲面造型方面对于给定的函数将会有更小的近似误差。 展开更多
关键词 BERNSTEIN-KANTOROVICH算子 Riemann-liouville分数阶积分 Peetre’-K泛函 Vorononskaja定理
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:3
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作者 丁协平 《应用数学和力学》 EI CSCD 北大核心 2004年第6期563-571,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 集值映象组 非空交定理 广义矢量平衡问题组 乘积G凸空间
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Equivalence of crossed product of linear categories and generalized Maschke theorem 被引量:1
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作者 鹿道伟 王栓宏 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期258-260,共3页
Some sufficient and necessary conditions are given for the equivalence between two crossed product actions of Hopf algebra H on the same linear category, and the Maschke theorem is generalized. Based on the result of ... Some sufficient and necessary conditions are given for the equivalence between two crossed product actions of Hopf algebra H on the same linear category, and the Maschke theorem is generalized. Based on the result of the crossed product in the classic Hopf algebra theory, first, let A be a k-linear category and H be a Hopf algebra, and the two crossed products A#_σH and A#'_σH are isomorphic under some conditions. Then, let A#_σH be a crossed product category for a finite dimensional and semisimple Hopf algebra H. If V is a left A#σH-module and WC V is a submodule such that W has a complement as a left A-module, then W has a complement as a A#_σH-module. 展开更多
关键词 linear category inner action crossed product generalized Maschke theorem
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Noether's theorems of a fractional Birkhoffian system within Riemann-Liouville derivatives 被引量:17
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作者 周燕 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期281-288,共8页
The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding ... The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding transversality conditions are given. Secondly, from special to general forms, Noether's theorems of a standard Birhoffian system are given, which provide an approach and theoretical basis for the further research on the Noether symmetry of the fractional Birkhoffian system. Thirdly, the invariances of the fractional Pfaffian action under a special one-parameter group of infinitesimal transformations without transforming the time and a general one-parameter group of infinitesimal transformations with transforming the time are studied, respectively, and the corresponding Noether's theorems are established. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 fractional Birkhoffian system Noether's theorem fractional conserved quantity Riemann–liouville fractional derivative
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:4
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作者 DINGXie-ping 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期618-626,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 family of set-valued mapping nonempty intersection theorem system of generalized vector equilibrium problem product G-convex space
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Entropy-variation with resistance in a quantized RLC circuit derived by the generalized Hellmann-Feynman theorem 被引量:2
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作者 范洪义 徐学翔 胡利云 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期83-87,共5页
By virtue of the generalized Hellmann-Feynman theorem for the ensemble average, we obtain the internal energy and average energy consumed by the resistance R in a quantized resistance-inductance-capacitance (RLC) el... By virtue of the generalized Hellmann-Feynman theorem for the ensemble average, we obtain the internal energy and average energy consumed by the resistance R in a quantized resistance-inductance-capacitance (RLC) electric circuit. We also calculate the entropy-variation with R. The relation between entropy and R is also derived. By the use of figures we indeed see that the entropy increases with the increment of R. 展开更多
关键词 ENTROPY RLC circuit generalized Hellmann-Feynman theorem
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Liouville-Type Theorems for Some Integral Systems 被引量:2
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作者 Zhengce Zhang 《Applied Mathematics》 2010年第2期94-100,共7页
In this paper, Liouville-type theorems of nonnegative solutions for some elliptic integral systems are considered. We use a new type of moving plane method introduced by Chen-Li-Ou. Our new ingredient is the use of St... In this paper, Liouville-type theorems of nonnegative solutions for some elliptic integral systems are considered. We use a new type of moving plane method introduced by Chen-Li-Ou. Our new ingredient is the use of Stein-Weiss inequality instead of Maximum Principle. 展开更多
关键词 liouville theorem INTEGRAL System MOVING PLANE Method
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LIOUVILLE TYPE THEOREM FOR THE STATIONARY EQUATIONS OF MAGNETO-HYDRODYNAMICS 被引量:1
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作者 Simon SCHULZ 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期491-497,共7页
We show that any smooth solution(u, H) to the stationary equations of magnetohydrodynamics belonging to both spaces L^6(R^3) and BMO^(-1)(R^3) must be identically zero.This is an extension of previous results, all of ... We show that any smooth solution(u, H) to the stationary equations of magnetohydrodynamics belonging to both spaces L^6(R^3) and BMO^(-1)(R^3) must be identically zero.This is an extension of previous results, all of which systematically required stronger integrability and the additional assumption ▽u, ▽H∈L^2(R^3), i.e., finite Dirichlet integral. 展开更多
关键词 liouville theorem Caccioppoli INEQUALITY NAVIER-STOKES EQUATIONS MHD
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GRADIENT ESTIMATES AND LIOUVILLE THEOREMS FOR LINEAR AND NONLINEAR PARABOLIC EQUATIONS ON RIEMANNIAN MANIFOLDS 被引量:1
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作者 朱晓宝 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期514-526,共13页
In this article, we will derive local elliptic type gradient estimates for positive solutions of linear parabolic equations (△-e/et)u(x,t)+q(x,t)u^p(x,t)=0 and nonlinear parabolic equations (△-e/et)u(x,... In this article, we will derive local elliptic type gradient estimates for positive solutions of linear parabolic equations (△-e/et)u(x,t)+q(x,t)u^p(x,t)=0 and nonlinear parabolic equations (△-e/et)u(x,t)+h(x,t)u^p(x,t)=0(p 〉 1) on Riemannian manifolds.As applications, we obtain some theorems of Liouville type for positive ancient solutions of such equations. Our results generalize that of Souplet-Zhang ([1], Bull. London Math. Soc. 38(2006), 1045-1053) and the author ([2], Nonlinear Anal. 74 (2011), 5141-5146). 展开更多
关键词 Gradient estimate linear parabolic equation nonlinear parabolic equation liouville type theorem
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LIOUVILLE THEOREM FOR CHOQUARD EQUATION WITH FINITE MORSE INDICES 被引量:1
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作者 赵晓军 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期673-680,共8页
In this article, we study the nonexistence of solution with finite Morse index for the following Choquaxd type equation -△u=∫Rn|u(y)|p/|x-y|αdy|u(x)|p-2u(x) in RN,where N≥3,0〈α〈min {4,N}.Suppose tha... In this article, we study the nonexistence of solution with finite Morse index for the following Choquaxd type equation -△u=∫Rn|u(y)|p/|x-y|αdy|u(x)|p-2u(x) in RN,where N≥3,0〈α〈min {4,N}.Suppose that 2 〈 p 〈2N-α/N-2,we will show that this problem does not possess nontrivial solution with finite Morse index. While for p =2N-α/N-2,if i(u) 〈∞, then we have ∫RN∫RN|u(x)|p|u(y)|p dxdy 〈∞ and ∫RN|△u|2 dx=|∫RN∫RN|u(x)|p/|x-y|a dxdy. 展开更多
关键词 liouville type theorem Morse index Choquard equation
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Nonlinear Liouville Theorem in the Quaternionic Heisenberg Group 被引量:1
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作者 YANGQiao-hua ZHUFu-liu 《Wuhan University Journal of Natural Sciences》 CAS 2005年第2期355-357,共3页
This paper deals with the problem of the type triangle open_H f+ f^p =O inquaternionic Heisenberg group, where triangle open_H is the quaternionic Heisenberg Laplacian. Itis proved that, under suitable conditions on p... This paper deals with the problem of the type triangle open_H f+ f^p =O inquaternionic Heisenberg group, where triangle open_H is the quaternionic Heisenberg Laplacian. Itis proved that, under suitable conditions on p and /, the only solution of triangle open_H f+ f^p=O. 展开更多
关键词 quaternionic Heisenberg group sub-Lapla-cian nonlinear liouville theorem
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GENERALIZED BOCHNER'S THEOREM FOR RADIAL FUNCTION 被引量:5
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作者 Wu Zongmin (Fudan University, China) 《Analysis in Theory and Applications》 1997年第3期47-57,共11页
A radial function can be expressed by its generator through The positive definite of the function plays an important rote in the radial basis interpolation. We can naturally use Bochner's Theorem to check if is po... A radial function can be expressed by its generator through The positive definite of the function plays an important rote in the radial basis interpolation. We can naturally use Bochner's Theorem to check if is positive definite. This requires however a n-dhnensiotial Fourier transformation and it is not very easy to calculate. Furthermore in a lot of cases we will use for spaces of various dimensions too, then for every fixed n we need do the Fourier transformation once to check if the function is positive definite in the n-di-mensional space. The completely monotone function:, which is discussed in [4] is positive definite for arbitrary space dimensions. With this technique tve can very easily characterize the positive definite, of a radial function through its generator. Unfortunately there is only a very small subset of radial function which is completely monotone. Thus this criterion excluded a lot of interesting functions such as compactly supported radial function, whcih are very useful in application. Can we find some conditions (as the completely monotone function) only for the \-dimen simial Fourier transform of the generator epto characterize a radial function 9, which is positivedefinite in n-dimensional (fixed n) spacel In this paper we defined a kind of incompletelymonotone function of order a, for a= 0,,1/2 ,1,3/2,(we denote the function class by ICM) ,in this sence a normal positvie function is in ICM a positive monotone decreasing function is inICM and a positive monotone decreasing and convex function is in ICM2- Based on this definition we get a generalized Bochner's Theorem for radial function-. If dimensional Fouriertransform of the generator of a radial function can be written as , then corre-spending radial function (x) is positive definite as a n-variate function iff F is an incomplete-ly monotone function of order a= (n- 1 )/2 (or simply In this way we have characterized the positive definite of the radial function as a n-vari-ate function through its generator in the sense of the Bocher's Theorem. 展开更多
关键词 generalized BOCHNER’S theorem FOR RADIAL FUNCTION very
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Integrating Factors and Conservation Theorems of Lagrangian Equations for Nonconservative Mechanical System in Generalized Classical Mechanics 被引量:2
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作者 QIAO Yong-Fen ZHAO Shu-Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期43-45,共3页
The conservation theorems of the generalized Lagrangian equations for nonconservative mechanical system are studied by using method of integrating factors. Firstly, the differential equations of motion of system are g... The conservation theorems of the generalized Lagrangian equations for nonconservative mechanical system are studied by using method of integrating factors. Firstly, the differential equations of motion of system are given, and the definition of integrating factors is given. Next, the necessary conditions for the existence of the conserved quantity are studied in detail. Finally, the conservation theorem and its inverse for the system are established, and an example is given to illustrate the application of the result. 展开更多
关键词 generalized nonconservative system Lagrangian equation conservation theorem integrating factor
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Generalized Hellmann-Feynman Theorem and Its Applications 被引量:1
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作者 孙鑫 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第12期40-44,共5页
The Hellmann-Feynman (H-F) theorem is generalized from stationary state to dynamical state. The generalized H-F theorem promotes molecular dynamics to go beyond adiabatic approximation and clears confusion in the Eh... The Hellmann-Feynman (H-F) theorem is generalized from stationary state to dynamical state. The generalized H-F theorem promotes molecular dynamics to go beyond adiabatic approximation and clears confusion in the Ehrenfest dynamics. 展开更多
关键词 is on in generalized Hellmann-Feynman theorem and Its Applications that for be of
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SATURATION THEOREMS FOR GENERALIZED BERNSTEIN POLYNOMIALS 被引量:1
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作者 Laiyi Zhu Qiu Lin 《Analysis in Theory and Applications》 2009年第3期242-253,共12页
In the present paper, we give the explicit formula of the principal part of ∑k=0^n({k}q-[n]qx)^sxk ∏m=0^n-k-1(1-q^mx) with respect to [n]q for any integer s and q ∈ (0, 1]. And, using the expressions, we obtai... In the present paper, we give the explicit formula of the principal part of ∑k=0^n({k}q-[n]qx)^sxk ∏m=0^n-k-1(1-q^mx) with respect to [n]q for any integer s and q ∈ (0, 1]. And, using the expressions, we obtain saturation theorems for Bn (f , qn,x) approximating to f(x) ∈ C[O, 1], 0 〈 qn ≤ 1, qn → 1. 展开更多
关键词 generalized Bernstein polynomial saturation theorem
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A LIOUVILLE THEOREM FOR STATIONARY INCOMPRESSIBLE FLUIDS OF VON MISES TYPE
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作者 Martin FUCHS Jan MüLLER 《Acta Mathematica Scientia》 SCIE CSCD 2019年第1期1-10,共10页
We consider entire solutions u of the equations describing the stationary flow of a generalized Newtonian fluid in 2 D concentrating on the question, if a Liouville-type result holds in the sense that the boundedness ... We consider entire solutions u of the equations describing the stationary flow of a generalized Newtonian fluid in 2 D concentrating on the question, if a Liouville-type result holds in the sense that the boundedness of u implies its constancy. A positive answer is true for p-fluids in the case p > 1(including the classical Navier-Stokes system for the choice p = 2), and recently we established this Liouville property for the Prandtl-Eyring fluid model,for which the dissipative potential has nearly linear growth. Here we finally discuss the case of perfectly plastic fluids whose flow is governed by a von Mises-type stress-strain relation formally corresponding to the case p = 1. It turns out that, for dissipative potentials of linear growth, the condition of μ-ellipticity with exponent μ < 2 is sufficient for proving the Liouville theorem. 展开更多
关键词 generalized NEWTONIAN FLUIDS perfectly plastic FLUIDS von MISES flow liouville theorem
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GENERALIZED RECIPROCAL THEOREMS AND THEIR APPLICATIONS
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作者 FU Bao-lian(付宝连) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第2期203-210,共8页
Generalized reciprocal theorems of non-coupled and coupled systems, which are valid for two deformed bodies with different constitutive relations are established by generalizing the idea of Betti's reciprocal theo... Generalized reciprocal theorems of non-coupled and coupled systems, which are valid for two deformed bodies with different constitutive relations are established by generalizing the idea of Betti's reciprocal theorem. When the constitutive relations of the two deformed bodies are all alike and linear elastic the generalized reciprocal theorem of non-coupled systems just becomes Betti's. Meanwhile the generalized reciprocal theorems are applied to simulate calculations in elasticity. 展开更多
关键词 reciprocal theorem generalized reciprocal theorem non-coupled system coupled system
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