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Some Symmetry Results for the A-Laplacian Equation via the Moving Planes Method
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作者 Zhongbo Fang Anna Wang 《Advances in Pure Mathematics》 2012年第6期363-366,共4页
In this paper, we are concerned with a positive solution of the non-homogeneous A-Laplacian equation in an open bounded connected domain. We use moving planes method to prove that the domain is a ball and the solution... In this paper, we are concerned with a positive solution of the non-homogeneous A-Laplacian equation in an open bounded connected domain. We use moving planes method to prove that the domain is a ball and the solution is radially symmetric. 展开更多
关键词 symmetry A-Laplacian MOVING planeS METHOD Overdetermined BOUNDARY Value Problem
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A Refinement of Extracting Approximate Symmetry Planes Based on Least Square
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作者 Jun Mao Hiroyuki Shioya 《Journal of Computer and Communications》 2014年第4期188-195,共8页
Extracting approximate symmetry planes is a challenge due to the difficulty of accurately measuring numerical values. Introducing the approximate symmetry planes of a 3D point set, this paper presents a new method by ... Extracting approximate symmetry planes is a challenge due to the difficulty of accurately measuring numerical values. Introducing the approximate symmetry planes of a 3D point set, this paper presents a new method by gathering normal vectors of potential of the planes, clustering the high probability ones, and then testing and verifying the planes. An experiment showed that the method is effective, robust and universal for extracting the complete approximate planes of symmetry of a random 3D point set. 展开更多
关键词 APPROXIMATE symmetry plane 3D Point Set Least SQUARES
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Hawking Radiation from Plane Symmetric Black Hole Covariant Anomaly
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作者 ZENG Xiao-Xiong HAN Yi-Wen YANG Shu-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期187-189,共3页
Based on the covariant anomaly cancellation method, which is believed to be more refined than the initial approach of Robinson and Wilczek, we discuss Hawking radiation from the plane symmetric black hole. The result ... Based on the covariant anomaly cancellation method, which is believed to be more refined than the initial approach of Robinson and Wilczek, we discuss Hawking radiation from the plane symmetric black hole. The result shows that Hawking radiation from the non-spherical symmetric black holes also can be derived from the viewpoint of anomaly. 展开更多
关键词 Hawking radiation covariant anomaly plane symmetry black hole
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Non-static plane symmetric inflationary Universe in scalar tensor theory
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作者 Rangavajhala Venkateswarlu Janjeti Satish Kakarlapati Pavan Kumar 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第6期636-642,共7页
Non-static plane symmetric cosmological solutions are presented in the presence of cosmic strings in the scalar-tensor theory of gravitation formulated by Sen & Dunn. It is shown that string cosmological models repre... Non-static plane symmetric cosmological solutions are presented in the presence of cosmic strings in the scalar-tensor theory of gravitation formulated by Sen & Dunn. It is shown that string cosmological models representing geometric strings (ρ = λ) and massive strings (ρ +λ = 0) do exist in this theory. Further, it is found that the Takabayasi string, i.e. ρ= (1 +ζ)λ, does not exist. Some physical and geometrical features of these models are discussed. 展开更多
关键词 string fields -- inflation -- plane symmetry -- acceleration of particles-- gravitation
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THE RADIAL SYMMETRY OF POSITIVE SOLUTIONS FOR SEMILINEAR PROBLEMS INVOLVING WEIGHTED FRACTIONAL LAPLACIANS
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作者 王英 邱妍静 尹青苹 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1020-1035,共16页
This paper deals with the radial symmetry of positive solutions to the nonlocal problem(-Δ)_(γ)~su=b(x)f(u)in B_(1){0},u=h in R~N B_(1),where b:B_1→R is locally Holder continuous,radially symmetric and decreasing i... This paper deals with the radial symmetry of positive solutions to the nonlocal problem(-Δ)_(γ)~su=b(x)f(u)in B_(1){0},u=h in R~N B_(1),where b:B_1→R is locally Holder continuous,radially symmetric and decreasing in the|x|direction,F:R→R is a Lipschitz function,h:B_1→R is radially symmetric,decreasing with respect to|x|in R^(N)/B_(1),B_(1) is the unit ball centered at the origin,and(-Δ)_γ~s is the weighted fractional Laplacian with s∈(0,1),γ∈[0,2s)defined by(-△)^(s)_(γ)u(x)=CN,slimδ→0+∫R^(N)/B_(δ)(x)u(x)-u(y)/|x-y|N+2s|y|^(r)dy.We consider the radial symmetry of isolated singular positive solutions to the nonlocal problem in whole space(-Δ)_(γ)^(s)u(x)=b(x)f(u)in R^(N)\{0},under suitable additional assumptions on b and f.Our symmetry results are derived by the method of moving planes,where the main difficulty comes from the weighted fractional Laplacian.Our results could be applied to get a sharp asymptotic for semilinear problems with the fractional Hardy operators(-Δ)^(s)u+μ/(|x|^(2s))u=b(x)f(u)in B_(1)\{0},u=h in R^(N)\B_(1),under suitable additional assumptions on b,f and h. 展开更多
关键词 radial symmetry fractional Laplacian method of moving planes
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SYMMETRY OF POSITIVE SOLUTIONS FOR THE FRACTIONAL HARTREE EQUATION 被引量:1
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作者 Xiangqing Liu 《Acta Mathematica Scientia》 SCIE CSCD 2019年第6期1508-1516,共9页
In this paper, by using the method of moving planes, we are concerned with the symmetry and monotonicity of positive solutions for the fractional Hartree equation.
关键词 the FRACTIONAL HARTREE equation positive solutions RADIAL symmetry MONOTONICITY the method of moving plane
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On Cyclically Symmetric Crack Problems 被引量:1
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作者 Lu Jianke 《Wuhan University Journal of Natural Sciences》 CAS 1997年第2期6-12,共7页
The first fundamental problems in the infinite plane with cracks and boundary values cyclically symmetric are considered. They are reduced to singular integral equations on a single crack, which would considerably sim... The first fundamental problems in the infinite plane with cracks and boundary values cyclically symmetric are considered. They are reduced to singular integral equations on a single crack, which would considerably simplify the process of method of solution for such problems. Some special cases are illustrated. 展开更多
关键词 basic region of cyclic symmetry cyclic constant Kolosov functions plane crack problems singular integral equations
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NONEXISTENCE AND SYMMETRY OF SOLUTIONS TO SOME FRACTIONAL LAPLACIAN EQUATIONS IN THE UPPER HALF SPACE
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作者 郭艳艳 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期836-851,共16页
In this article, we consider the fractional Laplacian equation {(-△)α/2u=k(x)f(u),x∈Rn+, u=0, x Rn+, where 0 〈α 〈 2,En+:= {x = (x1,x2,… ,xn)|xn〉 0}. When K is strictly decreasing with respect to ... In this article, we consider the fractional Laplacian equation {(-△)α/2u=k(x)f(u),x∈Rn+, u=0, x Rn+, where 0 〈α 〈 2,En+:= {x = (x1,x2,… ,xn)|xn〉 0}. When K is strictly decreasing with respect to |x'|, the symmetry of positive solutions is proved, where x' = (x1, x2,…, xn-1) ∈Rn- 1. When K is strictly increasing with respect to xn or only depend on xn, the nonexistence of positive solutions is obtained. 展开更多
关键词 Fractional Laplacian method of moving planes radial symmetry NONEXISTENCE
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ALTERNATIVE DESCRIPTION OF THE SHEAR PLANE OF THE R-PHASE
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作者 Q.B. Yang and J.A. Wert (Dept. of Physics, Xiangtan University, Xiangtan 411105, China)(Dept. of Materials Science & Engineering, University of Virginia, Charlottesville, VA 22903-4402, USA) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第5期313-317,共5页
A high density of {110} shear planes has been observed in the R-phase (Al5CuLi3)following phase transformation from the AlCuLi icosahedral Phase. The Present paper shows that the atomic arrangement in the vicinity of ... A high density of {110} shear planes has been observed in the R-phase (Al5CuLi3)following phase transformation from the AlCuLi icosahedral Phase. The Present paper shows that the atomic arrangement in the vicinity of the shear planes can be described as a two-dimensional periodic array of atom clusters with 5-fold symmetry. This result is obtained by projecting along the [1. 618...01] direction of the atomic positions from four adjacent lattice planes that cross the shear plane. The projection reveals that the shear plane consists of pentagonal arrangements of double triacontahedra,each pentagon incorporating 606 atoms. The calculated diffraction pattern from the pentagon has approximate 10-fold symmetry characteristic of a quasicrystal. 展开更多
关键词 shear plane R-phase symmetry double triacontahedra
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Ermakov System and Plane Curve Motions in Affine Geometries
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作者 QUChang-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期201-204,共4页
It is shown that the Pinney equation, Ermakov systems, and their higher-order generalizations describeself-similar solutions of plane curve motions in centro-affine and affine geometries.
关键词 Pinney equation Ermakov system motion of plane curve affine geometry symmetry group
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Some Steiner Symmetry Results in Overdetermined Boundary Value Problem
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作者 Zhongbo Fang Anna Wang 《Advances in Pure Mathematics》 2011年第6期340-344,共5页
In this paper, we use the moving planes method to prove that the domain Ω and the solution u are Steiner symmetric if u is a positive solution of the overdetermined boundary value problem in Ω.
关键词 STEINER symmetry MOVING planeS Method Overdetermined BOUNDARY Value Problem
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Group—Invariant Solutions in Plane Curve Motions
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作者 QUChang-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4期401-404,共4页
Group-invariant solutions to certain plane curve motions in Euclidean and centro-affine geometries areobtained. The behavior of some solutions is also presented.
关键词 motion of plane curves centro-affine geometry symmetry group spiral wave solution
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Symmetry and monotonicity of positive solutions to Schr?dinger systems with fractional p-Laplacians
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作者 MA Ling-wei ZHANG Zhen-qiu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第1期52-72,共21页
In this paper,we first establish narrow region principle and decay at infinity theorems to extend the direct method of moving planes for general fractional p-Laplacian systems.By virtue of this method,we investigate t... In this paper,we first establish narrow region principle and decay at infinity theorems to extend the direct method of moving planes for general fractional p-Laplacian systems.By virtue of this method,we investigate the qualitative properties of positive solutions for the following Schrodinger system with fractional p-Laplacian{(-△)^(s)_(p)u+au^(p-1)=f(u,v),(-△)^(t)_(p)v+bv(p-1)=g(u,v),where 0<s,t<1 and 2<p<∞.We obtain the radial symmetry in the unit ball or the whole space R^(N)(N≥2),the monotonicity in the parabolic domain and the nonexistence on the half space for positive solutions to the above system under some suitable conditions on f and g,respectively. 展开更多
关键词 fractional p-Laplacian Schr?dinger systems direct method of moving planes radial symmetry MONOTONICITY NONEXISTENCE
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基于六阶波像差理论的非球面大孔径折反射成像系统像差优化方法
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作者 曹一青 沈志娟 吕丽军 《量子电子学报》 CAS CSCD 北大核心 2024年第1期67-77,共11页
大孔径折反射成像系统被广泛应用于机器人导航和安全监控等领域。首先分析了超大视场光学系统六阶波像差理论应用于非球面光学系统的像差计算方法,随后基于该六阶波像差理论,构建了非球面大孔径折反射成像系统像差优化评价目标函数,并... 大孔径折反射成像系统被广泛应用于机器人导航和安全监控等领域。首先分析了超大视场光学系统六阶波像差理论应用于非球面光学系统的像差计算方法,随后基于该六阶波像差理论,构建了非球面大孔径折反射成像系统像差优化评价目标函数,并给出了求解这种包含多个光学参量的目标函数的优化算法,得到优化后的系统结构参数。最后,应用所提方法设计了一款工作波段为400~700 nm、最大视场角为120°、 F数为2.6且成像质量较好的光学系统。设计案例的结果表明所提出方法是有效的,为非球面大孔径折反射成像系统像差优化提供了一种有效手段。 展开更多
关键词 几何光学 像差优化 非球面 大孔径 平面对称
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Radial solution of the Logarithmic Laplacian system
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作者 ZHANG Li-hong NIE Xiao-feng +1 位作者 WANG Guo-tao Bashir Ahmad 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期114-124,共11页
The paper generalizes the direct method of moving planes to the Logarithmic Laplacian system.Firstly,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at infinity.Then,the ... The paper generalizes the direct method of moving planes to the Logarithmic Laplacian system.Firstly,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at infinity.Then,the radial symmetry of the solution of the Logarithmic Laplacian system is obtained. 展开更多
关键词 the Logarithmic Laplacian system radial symmetry the direct method of moving planes
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分数阶p-拉普拉斯抛物方程解的单调性和对称性
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作者 黄洪鸿 钟延生 《福建师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期83-89,共7页
讨论有界域上分数阶p-拉普拉斯抛物方程,应用移动平面法,得到了该方程有界正解关于分变量x_(1)∈(-∞,0]单调递增,进而证明其关于超平面T_(0)■{x∈R^(n)|x_(1)=0}对称。
关键词 移动平面法 分数阶p-拉普拉斯 对称性 单调性
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混合局部-非局部椭圆方程奇异解的单调性和对称性
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作者 代吉永芷 王逸如 黄水波 《数学物理学报(A辑)》 CSCD 北大核心 2024年第2期453-464,共12页
该文运用移动平面法研究了一类混合局部-非局部半线性椭圆方程奇异解的单调性和对称性.
关键词 混合局部-非局部 椭圆方程 对称性 单调性 移动平面法
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巧用数学定义探究平面镜成像
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作者 裴会明 权亮 《物理实验》 2024年第5期54-57,共4页
从实验方法和实验器材2方面对探究平面镜成像实验进行改进.改变实验方法,利用轴对称定义,简化了传统实验流程,减小了实验误差;改变实验器材,利用磁性材料,解决了平面镜与底座难以垂直的问题以及物点和像点的精准描画问题.改进后的实验... 从实验方法和实验器材2方面对探究平面镜成像实验进行改进.改变实验方法,利用轴对称定义,简化了传统实验流程,减小了实验误差;改变实验器材,利用磁性材料,解决了平面镜与底座难以垂直的问题以及物点和像点的精准描画问题.改进后的实验装置设计合理、操作简便,适合用于演示实验教学. 展开更多
关键词 平面镜成像 轴对称 磁性材料 精准定位
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一类分数阶Laplace方程解的径向对称性研究
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作者 李升萍 周长亮 《江西科学》 2024年第1期1-6,共6页
通过直接移动平面法研究了一类具有以下形式的分数阶Laplace方程,(-Δ)^(α/2) u(x)=|x|^(β)u^(p)(x)+|x|^(γ)u^(q)(x),x∈R^(n),0<α<2,n≥3。得到了其在全空间及不同约束条件下方程正解的径向对称性。
关键词 分数阶Laplace方程 移动平面法 径向对称性
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一种用于逆向工程的对称平面重建方法 被引量:4
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作者 金涛 许跃敏 童水光 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2002年第6期702-706,共5页
在对称实物测量造型中,基于对称面进行模型重建可以减少测量数据量、精确重建对称特征和保证实物的对称性.由此提出了一种用于实物测量造型的对称基准平面重建方法.首先选择一组对称特征,然后将测量数据点投影在一初始平面上并用折线连... 在对称实物测量造型中,基于对称面进行模型重建可以减少测量数据量、精确重建对称特征和保证实物的对称性.由此提出了一种用于实物测量造型的对称基准平面重建方法.首先选择一组对称特征,然后将测量数据点投影在一初始平面上并用折线连结,旋转初始平面使两条折线重合,可以得到一个与对称平面平行的平面.接着再移动平行平面,使对称特征到它的距离相等,这时的位置平面即为所求的对称平面.此方法已在逆向工程数据前处理系统中实现,并应用于摩托车外形塑件的逆向工程. 展开更多
关键词 对称平面重建方法 逆向工程 对称面 对称特征 模型重建 实物测量造型 机械产品 CAD
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