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基于张量的图象边缘检测及滤波 被引量:3
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作者 王晓明 顾晓东 刘健 《中国图象图形学报(A辑)》 CSCD 北大核心 2002年第8期780-782,共3页
边缘检测是数字图象处理中一种重要的处理手段 ,目前普遍采用的方法是基于直角坐标系下的 L aplacian算子 ,取其零交叉位置来检测 .而现实中 ,往往可见到许多曲面上的图象 ,比如柱面贴图 ,球面贴图 ,动态景物的数字化效果以及三维医学图... 边缘检测是数字图象处理中一种重要的处理手段 ,目前普遍采用的方法是基于直角坐标系下的 L aplacian算子 ,取其零交叉位置来检测 .而现实中 ,往往可见到许多曲面上的图象 ,比如柱面贴图 ,球面贴图 ,动态景物的数字化效果以及三维医学图象 ,结合深度信息采用基于微分几何曲线坐标系下的算子进行图象边缘检测及滤波是一种新的尝试 .从结果可以看到 ,处理效果明显优于普通的方法 . 展开更多
关键词 曲线坐标系 laplacian算子 边缘检测 扩散方程 图象滤波 数字图象处理 计算机视觉 张量
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曲面混合网格优化算法的研究 被引量:3
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作者 徐勇 翟建军 +1 位作者 陈文亮 张胜 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2004年第2期76-79,共4页
提出一种基于Laplacian方程的曲面混合网格优化算法 ,该算法首先对曲面边界进行预处理 ,然后对基于内部结点的网格单元进行调整 ,根据所要求的网格尺寸和精度 ,采用Laplacian及优化光顺方法进行网格优化 .结果表明 ,该算法可以保证在满... 提出一种基于Laplacian方程的曲面混合网格优化算法 ,该算法首先对曲面边界进行预处理 ,然后对基于内部结点的网格单元进行调整 ,根据所要求的网格尺寸和精度 ,采用Laplacian及优化光顺方法进行网格优化 .结果表明 ,该算法可以保证在满足指定精度要求的条件下 ,得到更合理的曲面混合网格 。 展开更多
关键词 三角形网格 四边形网格 网格优化 laplacian方程
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On the Cauchy Problem of Evolution p-Laplacian Equation with Nonlinear Gradient Term 被引量:7
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作者 Mingyu CHEN Junning ZHAO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2009年第1期1-16,共16页
The authors study the existence of solution to p-Laplacian equation with nonlinear forcing term under optimal assumptions on the initial data, which are assumed to be measures. The existence of local solution is obtai... The authors study the existence of solution to p-Laplacian equation with nonlinear forcing term under optimal assumptions on the initial data, which are assumed to be measures. The existence of local solution is obtained. 展开更多
关键词 p-laplacian equation Nonlinear gradient term Measures initial data Local solution
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Life-Spans and Blow-Up Rates for aρ-Laplacian Parabolic Equation with General Source
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作者 LONG Qunfei 《Journal of Partial Differential Equations》 CSCD 2024年第2期187-197,共11页
This article investigates the blow-up results for the initial boundary value problem to the quasi-linear parabolic equation with p-Laplacian■where p≥2 and the function f(u)satisfies■for some positive constantsα,β... This article investigates the blow-up results for the initial boundary value problem to the quasi-linear parabolic equation with p-Laplacian■where p≥2 and the function f(u)satisfies■for some positive constantsα,β,γwith 0<■,which has been studied under the initial condition Jp(u0)<0.This paper generalizes the above results on the following aspects:a new blow-up condition is given,which holds for all p>2;a new blow-up condition is given,which holds for p=2;some new lifespans and upper blow-up rates are given under certain conditions. 展开更多
关键词 P-laplacian parabolic equation blow-ups life-spans blow-up rates
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Caputo型分数阶微分系统正解的唯一性
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作者 徐紫钰 吴克晴 《广西师范大学学报(自然科学版)》 CAS 北大核心 2023年第6期92-104,共13页
考虑一类非线性p-Laplacian分数阶微分方程耦合系统多点边值问题,其中非线性函数包含Caputo分数阶导数,其边界条件包含非线性积分项。基于和算子的广义不动点定理及分数阶微积分算子的性质,分析该耦合系统的唯一正解;借助相应算子方程... 考虑一类非线性p-Laplacian分数阶微分方程耦合系统多点边值问题,其中非线性函数包含Caputo分数阶导数,其边界条件包含非线性积分项。基于和算子的广义不动点定理及分数阶微积分算子的性质,分析该耦合系统的唯一正解;借助相应算子方程推导出唯一正解的存在性;通过数值算例对主要结果进行检验分析。 展开更多
关键词 正解 分数阶导数 算子方程 P-laplacian 唯一性
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有限元在闸基渗流计算中的应用 被引量:4
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作者 宋春发 《水利科技与经济》 2005年第2期75-76,92,共3页
 建立闸基渗流数学模型,确定渗流场域和单元体,给出工程实例。
关键词 闸基渗流 渗流场 工程实例 有限元 计算 单元
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A priori estimates and blow-up behavior for solutions of-QNu- Veu in bounded domain in R^N 被引量:2
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作者 XIE Ru Long GONG Hua Jun 《Science China Mathematics》 SCIE CSCD 2016年第3期479-492,共14页
Let Q_N be an N-anisotropic Laplacian operator, which contains the ordinary Laplacian operator,N-Laplacian operator and the anisotropic Laplacian operator. We firstly obtain the properties of Q_N, which contain the we... Let Q_N be an N-anisotropic Laplacian operator, which contains the ordinary Laplacian operator,N-Laplacian operator and the anisotropic Laplacian operator. We firstly obtain the properties of Q_N, which contain the weak maximal principle, the comparison principle and the mean value property. Then a priori estimates and blow-up analysis for solutions of-Q_(N^u) = Ve^u in bounded domain in R^N, N≥2 are established.Finally, the blow-up behavior of the only singular point is also considered. 展开更多
关键词 blow-up behavior N-anisotropic laplacian N-anisotropic Liouville equation
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Stochastic 3D Leray-α model with fractional dissipation
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作者 Shihu Li Wei Liu Yingchao Xie 《Science China Mathematics》 SCIE CSCD 2023年第11期2589-2614,共26页
In this paper,we establish the global well-posedness of the stochastic 3D Leray-αmodel with general fractional dissipation driven by multiplicative noise.This model is the stochastic 3D Navier-Stokes equations regula... In this paper,we establish the global well-posedness of the stochastic 3D Leray-αmodel with general fractional dissipation driven by multiplicative noise.This model is the stochastic 3D Navier-Stokes equations regularized through a smoothing kernel of orderθ1 in the nonlinear term and theθ2-fractional Laplacian.In the case ofθ1≥0 andθ2>0 withθ1+θ2≥5/4,we prove the global existence and uniqueness of strong solutions.The main results not only cover many existing works in the deterministic cases,but also generalize some known results of stochastic models such as the stochastic hyperviscous Navier-Stokes equations and classical stochastic3D Leray-αmodel as the special cases. 展开更多
关键词 stochastic Leray-Q model fractional laplacian stochastic Navier-Stokes equation WELL-POSEDNESS
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Global Existence and Finite Time Blow-up for the m-Laplacian Parabolic Problem
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作者 Yue PANG Vicentiu D.RADULESCU Run Zhang XU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2023年第8期1497-1524,共28页
In this paper,we consider an initial boundary value problem of m-Laplacian parabolic equation arising in various physical models.We tackle this problem at three different initial energy levels.For the sub-critical ini... In this paper,we consider an initial boundary value problem of m-Laplacian parabolic equation arising in various physical models.We tackle this problem at three different initial energy levels.For the sub-critical initial energy,we obtain the blow-up result and estimate the lower and upper bounds of the blow-up time.For the critical initial energy,we show the global existence,asymptotic behavior,finite time blow-up and the lower bound of the blow-up time.For the sup-critical initial energy,we prove the finite time blow-up and estimate the lower and upper bounds of the blow-up time. 展开更多
关键词 m-laplacian parabolic equation BLOW-UP blow-up time global existence
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SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
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作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-laplacian equation boundary blow-up sub-supersolution method EXISTENCE nonexistence and estimates sufficient and necessary conditions
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Kirchhoff-Type Problem with Mixed Boundary Condition in a Variable Exponent Sobolev
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作者 Junichi Aramaki 《Communications in Mathematical Research》 CSCD 2023年第4期539-574,共36页
.In this paper,we consider a mixed boundary value problem for the stationary Kirchhoff-type equation containing p(-)-Laplacian.More precisely,we are concerned with the problem with the Dirichlet condition on a part of... .In this paper,we consider a mixed boundary value problem for the stationary Kirchhoff-type equation containing p(-)-Laplacian.More precisely,we are concerned with the problem with the Dirichlet condition on a part of the boundary and the Steklov boundary condition on an another part of the boundary.We show the existence of at least one,two or infinitely many non-trivial weak solutions according to hypotheses on given functions. 展开更多
关键词 Kirchhoff-type problem mixed boundary value problem p(-)-laplacian type equation weak solutions
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Viscosity Solutions to a Parabolic Inhomogeneous Equation Associated with Infinity Laplacian
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作者 Fang LIU Xiao Ping YANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2015年第2期255-271,共17页
We obtain the existence and uniqueness results of viscosity solutions to the initial and boundary value problem for a nonlinear degenerate and singular parabolic inhomogeneous equation of the form ut-△ ∞N u=f, wher... We obtain the existence and uniqueness results of viscosity solutions to the initial and boundary value problem for a nonlinear degenerate and singular parabolic inhomogeneous equation of the form ut-△ ∞N u=f, where An denotes the so-called normalized infinity Laplacian given by △∞ Nu=1/|Du|2〈D2uDu,Du〉. 展开更多
关键词 Parabolic equation infinity laplacian viscosity solution inhomogeneous equation comparison principle EXISTENCE
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有限元在闸基渗流计算中的应用 被引量:2
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作者 宋春发 《安徽水利水电职业技术学院学报》 2005年第1期20-22,39,共4页
建立闸基渗流数学模型,确定渗流场域和单元体,给出工程实例。
关键词 闸基渗流 渗流场 工程实例 有限元 计算 单元
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最低次混合有限元方法的最优L^∞误差估计
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作者 陈焕祯 《应用数学学报》 CSCD 北大核心 1998年第4期609-617,共9页
本文对拉普拉斯方程的最低次混合元方法提出了构造混合元空间的充分条件,并建立了新的插值算子.据此得到了混合元解,伴随向量函数及其散度的最优L∞误差估计.
关键词 拉普拉斯方程 最低次混合元 误差估计 有限元
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关于自然边界小波元刚度矩阵的条件数 被引量:2
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作者 陈文胜 张永虎 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第5期12-16,共5页
应用EQuak 小波方法和自然边界元方法于单位圆内Laplace 方程的Neumann 边值问题得到了自然边界元刚度矩阵的条件数为O( N) ,其中N
关键词 LAPLACE方程 小波 刚度矩阵 条件数 自然边界元
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带有临界型非线性项的强阻尼波动方程的整体吸引子 被引量:2
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作者 张庆华 李刚 《应用数学学报》 CSCD 北大核心 2017年第2期192-203,共12页
本文研究一类带有临界型非线性项的强阻尼波动方程.当指数1/2<θ<1时,利用能量泛函的性质,我们证明了由方程导出的C_0半群T(t)的紧性和耗散性,以及整体吸引子的存在性.当θ=1时,利用磨光与逼近,我们研究了磨光半群T_v(t)随t→∞... 本文研究一类带有临界型非线性项的强阻尼波动方程.当指数1/2<θ<1时,利用能量泛函的性质,我们证明了由方程导出的C_0半群T(t)的紧性和耗散性,以及整体吸引子的存在性.当θ=1时,利用磨光与逼近,我们研究了磨光半群T_v(t)随t→∞时的一致渐近行为,以及它们在任意有界区间上强收敛到T(t)的一致性,并把T(t)的整体吸引子表示为磨光半群T_v(t)整体吸引子的上半极限. 展开更多
关键词 负拉普拉斯算子 强阻尼 波动方程 临界型非线性项 能量泛函 整体吸引子
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拟线性非齐次椭圆方程正解的存在性
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作者 刘英 《淮阴师范学院学报(自然科学版)》 CAS 2010年第4期291-294,共4页
讨论了一类拟线性非齐次椭圆方程正解的存在性.在非线性项不满足(A.R)条件的情况下,利用山路引理得到了方程至少存在两个正解.
关键词 椭圆方程 laplacian方程 正解 (A.R)条件 (ps)列
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POSITIVE SOLUTIONS TO HYBRID SCHR?DINGER EQUATION WITH NORMAL AND FRACTIONAL LAPLACIANS
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作者 Xiaoqing Wen Lina Wang Hongwei Yin 《Annals of Applied Mathematics》 2015年第4期446-451,共6页
In this paper, we study the hybrid Schrodinger equation involving normal and fractional Laplace operator, and obtain the existence of the solutions to this class of the hybrid partial differential equation. Our main a... In this paper, we study the hybrid Schrodinger equation involving normal and fractional Laplace operator, and obtain the existence of the solutions to this class of the hybrid partial differential equation. Our main argument is variational methods. 展开更多
关键词 Schrodinger equation variational methods fractional laplacian
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Existence of Viscosity Solutions to a Parabolic Inhomogeneous Equation Associated with Infinity Laplacian
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作者 Fang Liu 《Journal of Applied Mathematics and Physics》 2015年第5期488-495,共8页
In this paper, we obtain the existence result of viscosity solutions to the initial and boundary value problem for a nonlinear degenerate parabolic inhomogeneous equation of the form , where denotes infinity Laplacian... In this paper, we obtain the existence result of viscosity solutions to the initial and boundary value problem for a nonlinear degenerate parabolic inhomogeneous equation of the form , where denotes infinity Laplacian given by . 展开更多
关键词 INFINITY laplacian VISCOSITY Solution INHOMOGENEOUS equation
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The Heat Equation for the Dirichlet Fractional Laplacian with Negative Potentials:Existence and Blow-up of Nonnegative Solutions
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作者 Ali BEN AMOR Tarek KENZIZI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2017年第7期981-995,共15页
We establish conditions ensuring either existence or blow-up of nonnegative solutions for the heat equation generated by the Dirichlet fractional Laplacian perturbed by negative potentials on bounded sets. The elabora... We establish conditions ensuring either existence or blow-up of nonnegative solutions for the heat equation generated by the Dirichlet fractional Laplacian perturbed by negative potentials on bounded sets. The elaborated theory is supplied by some examples. 展开更多
关键词 Fractional laplacian heat equation Dirichlet form BLOW-UP
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