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一种同时反演纵波速度和泊松比的方法 被引量:18
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作者 姜秀娣 刘洋 +1 位作者 魏修成 黄捍东 《地球物理学进展》 CSCD 北大核心 2005年第2期314-318,共5页
本文提出一种角度部分叠加资料同时反演纵波速度和泊松比的方法.以角度部分叠加资料为基础,利用地震波振幅随入射角变化与弹性参数间的数学关系,基于非线性最优化理论,通过将最小平方问题转化为大型带状矩阵的求解问题,采用测井约束逐... 本文提出一种角度部分叠加资料同时反演纵波速度和泊松比的方法.以角度部分叠加资料为基础,利用地震波振幅随入射角变化与弹性参数间的数学关系,基于非线性最优化理论,通过将最小平方问题转化为大型带状矩阵的求解问题,采用测井约束逐道外推技术依次求得该角度剖面每个点的纵波和泊松比值.通过由每个角度叠加剖面反演得到的相应角度范围的纵波速度和泊松比剖面的对比分析,进一步得到地震波垂直入射时的纵波速度和泊松比,为地震资料的岩性及含气性解释提供丰富的参数信息. 展开更多
关键词 纵波速度 泊松比 非线性反演 海色矩阵 气层识别
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由路段交通量推算OD矩阵的一种有效方法及其应用 被引量:5
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作者 易昆南 李志纯 《运筹与管理》 CSCD 2002年第5期65-70,共6页
针对现有OD矩阵估计方法的不足 ,本文讨论了一种新的有效的估计方法 ,它包括一个路段流量的预处理过程 ,以消除路段观测流量的不相容 ,然后经过流量加载和卸载两个逆过程 ,进行反复迭代 ,最终得到再现路段交通量的OD矩阵 ,文中例证了该... 针对现有OD矩阵估计方法的不足 ,本文讨论了一种新的有效的估计方法 ,它包括一个路段流量的预处理过程 ,以消除路段观测流量的不相容 ,然后经过流量加载和卸载两个逆过程 ,进行反复迭代 ,最终得到再现路段交通量的OD矩阵 ,文中例证了该方法的有效性。 展开更多
关键词 交通量 OD矩阵 既约路网 poisson分布 交通管理
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电各向异性介质中泊松方程的具体形式 被引量:8
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作者 李文略 《泉州师范学院学报》 2015年第2期93-96,共4页
泊松方程是研究电各向异性介质静电场的核心方程.文章从泊松方程并矢表达式出发,应用张量分析的矩阵方法,推导出电各向异性介质中泊松方程在球坐标系和柱坐标下的具体形式,即A1+A2+A3+A4=-ρ和B1+B2+B3+B4=-ρ.并得出介电常数张量ε→... 泊松方程是研究电各向异性介质静电场的核心方程.文章从泊松方程并矢表达式出发,应用张量分析的矩阵方法,推导出电各向异性介质中泊松方程在球坐标系和柱坐标下的具体形式,即A1+A2+A3+A4=-ρ和B1+B2+B3+B4=-ρ.并得出介电常数张量ε→→具有坐标系下的不变性,这有助于加深对电各向导性介质的介电属性的了解. 展开更多
关键词 电各向异性介质 泊松方程 张量 矩阵
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有限元并行计算的MPI程序设计 被引量:4
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作者 雒战平 刘之行 《西安交通大学学报》 EI CAS CSCD 北大核心 2004年第8期873-876,共4页
以Poisson方程边值问题的求解为背景,实现了有限元并行计算的MPI程序设计.通过生成一种特殊结构的刚度矩阵,并在此基础上,设计了一套有效的并行计算策略,使计算的并行性得到很好的开拓,实现了包括刚度矩阵的生成、刚度矩阵的三角分解以... 以Poisson方程边值问题的求解为背景,实现了有限元并行计算的MPI程序设计.通过生成一种特殊结构的刚度矩阵,并在此基础上,设计了一套有效的并行计算策略,使计算的并行性得到很好的开拓,实现了包括刚度矩阵的生成、刚度矩阵的三角分解以及解三角方程组的并行执行.程序在国家高性能计算中心(西安)的曙光3000上进行了数值试验,结果表明,随着开辟进程数目的增多,加速比变得比较理想,当进程数目为30时,表明该进程数目在最优进程值附近.在60台处理器(进程)上计算18万个节点的大规模问题时,共耗时176 96415s. 展开更多
关键词 并行计算 分布式存储 数据结构 有限元方法 MPI编程
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Local MFS Matrix Decomposition Algorithms for Elliptic BVPs in Annuli
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作者 C.S.Chen Andreas Karageorghis Min Lei 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE CSCD 2024年第1期93-120,共28页
We apply the local method of fundamental solutions(LMFS)to boundary value problems(BVPs)for the Laplace and homogeneous biharmonic equations in annuli.By appropriately choosing the collocation points,the LMFS discreti... We apply the local method of fundamental solutions(LMFS)to boundary value problems(BVPs)for the Laplace and homogeneous biharmonic equations in annuli.By appropriately choosing the collocation points,the LMFS discretization yields sparse block circulant system matrices.As a result,matrix decomposition algorithms(MDAs)and fast Fourier transforms(FFTs)can be used for the solution of the systems resulting in considerable savings in both computational time and storage requirements.The accuracy of the method and its ability to solve large scale problems are demonstrated by applying it to several numerical experiments. 展开更多
关键词 Local method of fundamental solutions poisson equation biharmonic equation matrix decomposition algorithms fast Fourier transforms
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Poisson Matrices on 3-Manifolds and Their Applications to 3-CPM Manifolds 被引量:1
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作者 Hong Jun LI Science School. Xi’an Jiaotong University, Xi’an 710049, P. R. China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2001年第4期697-714,共18页
In this paper, the existence of a global tangent frame on every oriented and connected smooth 3-manifold will be used to develop a global frame method in 3-dimensional geometry and topology. Corresponding to each glob... In this paper, the existence of a global tangent frame on every oriented and connected smooth 3-manifold will be used to develop a global frame method in 3-dimensional geometry and topology. Corresponding to each global tangent frame, we define a Poisson matrix on the 3-manifold. And using it as an initial date. we give an explicit expression of all the curvatures for some Riemannian metric. The method is well applied to 3-manifolds with constant Poisson matrix. Such 3-manifolds are essentially the homogeneous spaces of 3-dimensional Lie groups. 展开更多
关键词 Global frames poisson matrix CURVATURE 3-CPM manifolds Homogeneous spaces
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基于马尔科夫过程的卫生装备配置研究 被引量:2
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作者 郭立军 张晓峰 +1 位作者 陶学强 王兴永 《医疗卫生装备》 CAS 2017年第3期21-24,共4页
目的:通过伤员伤势转换分析和卫生装备随机服务过程分析,解决考虑伤员伤势分布随机性和动态性条件下的卫生装备配置问题。方法:通过分析伤员状态转换过程,利用泊松随机过程和马尔科夫链构建救治机构伤员队列变化模型,分析救治机构卫生... 目的:通过伤员伤势转换分析和卫生装备随机服务过程分析,解决考虑伤员伤势分布随机性和动态性条件下的卫生装备配置问题。方法:通过分析伤员状态转换过程,利用泊松随机过程和马尔科夫链构建救治机构伤员队列变化模型,分析救治机构卫生装备随机服务过程,规划服务规则,通过专家调研获取状态转移参数,建立伤势自然转移参数和救治后伤员伤势更新向量,通过模拟工具求解卫生装备配置问题。结果:以野战医疗所急救台为分析对象,通过实例数据和模拟计算,求解出急救台最优配置,急救台配置求解结果与当前普遍实行的配置接近。结论:基于马尔科夫链过程对卫生装备配置进行求解,能够反映伤势变化和救治队列的波动性,求解结果较为可靠,求解方法具有较高的通用性和实用性,可以为卫生装备配置和优化等研究提供必要的方法支撑。 展开更多
关键词 马尔科夫链 泊松分布 转移矩阵 卫生装备配置 急救
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基于Log-sum惩罚的Poisson噪声下矩阵恢复算法 被引量:1
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作者 高萌萌 韩国栋 曹文飞 《工程数学学报》 CSCD 北大核心 2019年第5期489-503,共15页
在工程应用中,例如智能交通系统、数据挖掘以及距离测量等,大部分矩阵恢复模型均基于矩阵秩函数的凸松弛矩阵核范数而提出,并取得显著性的恢复效果.但是压缩感知的有关研究表明,凸松弛函数在信号恢复问题上有诸多局限性.因而,本文采用... 在工程应用中,例如智能交通系统、数据挖掘以及距离测量等,大部分矩阵恢复模型均基于矩阵秩函数的凸松弛矩阵核范数而提出,并取得显著性的恢复效果.但是压缩感知的有关研究表明,凸松弛函数在信号恢复问题上有诸多局限性.因而,本文采用非凸松弛函数来解决 Poisson噪声污染的矩阵恢复问题.具体来说,本文首先引入一个 Log-sum非凸函数正则的恢复模型;然后,我们为此模型设计一个高效的求解算法并分析了其收敛性质.模拟和实际数据的实验结果表明,本文提出的方法相比于现有方法具有良好的恢复性能. 展开更多
关键词 矩阵恢复 非凸松弛 Log-sum函数 poisson噪声
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Factorization of the Toda Hierarchy and Poisson Structure for Symplectic Maps
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作者 曾云波 《Tsinghua Science and Technology》 SCIE EI CAS 1997年第3期81-88,共8页
It is shown that each lattice equation in the Toda hierarchy can be factored by an integrable symplectic map and a finite dimensional integrable Hamiltonian system via higher order constraint relating the potential ... It is shown that each lattice equation in the Toda hierarchy can be factored by an integrable symplectic map and a finite dimensional integrable Hamiltonian system via higher order constraint relating the potential and square eigenfunctions. The classical Poisson structure and r matrix for the constrained flows are presented. 展开更多
关键词 FACTORIZATION r matrix classical poisson structure integrable symplectic map higher order constraint
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The r-matrix for constrained flows
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作者 曾云波 《Chinese Science Bulletin》 SCIE EI CAS 1996年第9期705-708,共4页
The classical r-matrix and Poisson structure play an important role in our studying ofintegrable systems, since they contain underlying property of the system. Recently, inter-est has developed in the study of dynamic... The classical r-matrix and Poisson structure play an important role in our studying ofintegrable systems, since they contain underlying property of the system. Recently, inter-est has developed in the study of dynamical r-matrix structure, which depends also on thedynamical variables, and associated generalized Yang-Baxter equations. However, 展开更多
关键词 R-matrix poisson STRUCTURE CONSTRAINED flow.
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Generalization of the Exact Solution of 1D Poisson Equation with Robin Boundary Conditions, Using the Finite Difference Method
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作者 Serigne Bira Gueye Kharouna Talla Cheikh Mbow 《Journal of Electromagnetic Analysis and Applications》 2014年第12期372-381,共10页
A new and innovative method for solving the 1D Poisson Equation is presented, using the finite differences method, with Robin Boundary conditions. The exact formula of the inverse of the discretization matrix is deter... A new and innovative method for solving the 1D Poisson Equation is presented, using the finite differences method, with Robin Boundary conditions. The exact formula of the inverse of the discretization matrix is determined. This is the first time that this famous matrix is inverted explicitly, without using the right hand side. Thus, the solution is determined in a direct, very accurate (O(h2)), and very fast (O(N)) manner. This new approach treats all cases of boundary conditions: Dirichlet, Neumann, and mixed. Therefore, it can serve as a reference for solving the Poisson equation in one dimension. 展开更多
关键词 Robin BOUNDARY poisson EQUATION matrix INVERSION
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Squeezed Coherent States in Non-Unitary Approach and Relation to Sub- and Super-Poissonian Statistics
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2017年第12期706-757,共52页
After developing the concept of displaced squeezed vacuum states in the non-unitary approach and establishing the connection to the unitary approach we calculate their quasiprobabilities and expectation values in gene... After developing the concept of displaced squeezed vacuum states in the non-unitary approach and establishing the connection to the unitary approach we calculate their quasiprobabilities and expectation values in general form. Then we consider the displacement of the squeezed vacuum states and calculate their photon statistics and their quasiprobabilities. The expectation values of the displaced states are related to the expectation values of the undisplaced states and are calculated for some simplest cases which are sufficient to discuss their categorization as sub-Poissonian and super-Poissonian statistics. A large set of these states do not belong to sub- or to super-Poissonian states but are also not Poissonian states. We illustrate in examples their photon distributions. This shows that the notions of sub- and of super-Poissonian statistics and their use for the definition of nonclassicality of states are problematic. In Appendix A we present the most important relations for SU (1,1) treatment of squeezing and the disentanglement of their operators. Some initial members of sequences of expectation values for squeezed vacuum states are collected in Appendix E. 展开更多
关键词 SU (1 1) Group of SQUEEZING and Rotation WIGNER Quasiprobability Unitary Approach to SQUEEZING NONCLASSICAL STATES Uncertainty matrix Distance of STATES Jacobi Ultraspherical LEGENDRE and Hermite Polynomials poisson STATISTICS
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Covariances of Linear Stochastic Differential Equations for Analyzing Computer Networks
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作者 樊华 山秀明 +1 位作者 袁坚 任勇 《Tsinghua Science and Technology》 SCIE EI CAS 2011年第3期264-271,共8页
Analyses of dynamic systems with random oscillations need to calculate the system covariance matrix, but this is not easy even in the linear case if the random term is not a Gaussian white noise. A universal method is... Analyses of dynamic systems with random oscillations need to calculate the system covariance matrix, but this is not easy even in the linear case if the random term is not a Gaussian white noise. A universal method is developed here to handle both Gaussian and compound Poisson white noise. The quadratic variations are analyzed to transform the problem into a Lyapunov matrix differential equation. Explicit formulas are then derived by vectorization. These formulas are applied to a simple model of flows and queuing in a computer network. A stability analysis of the mean value illustrates the effects of oscillations in a real system. The relationships between the oscillations and the parameters are clearly presented to improve designs of real systems. 展开更多
关键词 covariance matrix stochastic differential equation (SDE) compound poisson white noise transmission control protocol (TCP) flow
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Empirical Likelihood Statistical Inference for Compound Poisson Vector Processes under Infinite Covariance Matrix
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作者 程从华 《Journal of Donghua University(English Edition)》 CAS 2023年第1期122-126,共5页
The paper discusses the statistical inference problem of the compound Poisson vector process(CPVP)in the domain of attraction of normal law but with infinite covariance matrix.The empirical likelihood(EL)method to con... The paper discusses the statistical inference problem of the compound Poisson vector process(CPVP)in the domain of attraction of normal law but with infinite covariance matrix.The empirical likelihood(EL)method to construct confidence regions for the mean vector has been proposed.It is a generalization from the finite second-order moments to the infinite second-order moments in the domain of attraction of normal law.The log-empirical likelihood ratio statistic for the average number of the CPVP converges to F distribution in distribution when the population is in the domain of attraction of normal law but has infinite covariance matrix.Some simulation results are proposed to illustrate the method of the paper. 展开更多
关键词 compound poisson vector process(CPVP) infinite covariance matrix domain of attraction of normal law empirical likelihood(EL)
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Local RBF Algorithms for Elliptic Boundary Value Problems in Annular Domains 被引量:1
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作者 C.S.Chen Andreas Karageorghis 《Communications in Computational Physics》 SCIE 2019年第1期41-67,共27页
A local radial basis function method(LRBF)is applied for the solution of boundary value problems in annular domains governed by the Poisson equation,the inhomogeneous biharmonic equation and the inhomogeneous Cauchy-N... A local radial basis function method(LRBF)is applied for the solution of boundary value problems in annular domains governed by the Poisson equation,the inhomogeneous biharmonic equation and the inhomogeneous Cauchy-Navier equations of elasticity.By appropriately choosing the collocation points we obtain linear systems in which the coefficient matrices possess block sparse circulant structures and which can be solved efficiently using matrix decomposition algorithms(MDAs)and fast Fourier transforms(FFTs).The MDAs used are appropriately modified to take into account the sparsity of the arrays involved in the discretization.The leave-one-out cross validation(LOOCV)algorithm is employed to obtain a suitable value for the shape parameter in the radial basis functions(RBFs)used.The selection of the nearest centres for each local influence domain is carried out using a modification of the kdtree algorithm.In several numerical experiments,it is demonstrated that the proposed algorithm is both accurate and capable of solving large scale problems. 展开更多
关键词 Radial basis functions Kansa method poisson equation biharmonic equation Cauchy-Navier equations of elasticity matrix decomposition algorithms fast Fourier transforms
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利用Block-Pulse函数求解分数阶泊松方程数值解
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作者 赵绚 朱帅 +1 位作者 朱世昕 杨泽民 《数学的实践与认识》 2023年第4期231-237,共7页
借助于二维Block-Pulse函数求解分数阶泊松方程的数值解,并讨论了Dirichlet边界条件,方法是基于Block-Pulse函数的定义及性质,并结合相应的分数阶微分算子矩阵将原问题转化为含有未知变量的代数方程组,进而离散未知变量,求得原问题的数... 借助于二维Block-Pulse函数求解分数阶泊松方程的数值解,并讨论了Dirichlet边界条件,方法是基于Block-Pulse函数的定义及性质,并结合相应的分数阶微分算子矩阵将原问题转化为含有未知变量的代数方程组,进而离散未知变量,求得原问题的数值解.而且还对所提方法进行了误差分析,最后给出的数值算例也验证了所提算法的有效性及可行性. 展开更多
关键词 二维Block-Pulse函数 泊松方程 数值解 算子矩阵 分数阶
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r-Matrix Structure for a Restricted Flow with Bargmann Constraint
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作者 CHEN Jin-Bing GENG Xian-Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期393-395,共3页
This paper deals with the integrability of a finite-dimensional Hamiltonian system linked with the generalized coupled KdV hierarchy. For this purpose the associated Lax representation is presented after an elementary... This paper deals with the integrability of a finite-dimensional Hamiltonian system linked with the generalized coupled KdV hierarchy. For this purpose the associated Lax representation is presented after an elementary calculation. It is shown that the Lax representation enjoys a dynamical r-matrix formula instead of a classical one in the Poisson bracket on R2N. Consequently the resulting system is proved to be completely integrable in view of its r-matrix structure. 展开更多
关键词 poisson bracket Lax representation R-matrix Liouville integrability
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一个3×3谱问题产生的约束系统的动力r-矩阵
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作者 李灵晓 苏婷 《应用数学》 CSCD 北大核心 2008年第3期443-448,共6页
给出一个3×3谱问题产生的Harry-Dym型方程族的约束系统的Lax表示,动力r-矩阵及Poisson结构,并给出3N个守恒积分.从而利用一般r-矩阵理论证明了该约束系统在Liouville意义下的完全可积性.
关键词 约束系统 LAX表示 R-矩阵 poisson结构
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求解Poisson方程改进的交替方向隐式迭代格式
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作者 葛志昊 刘富豪 《工程数学学报》 CSCD 北大核心 2020年第1期67-74,共8页
本文以Poisson方程为例,在不对节点进行重新排列的前提下,通过求解较低维数的矩阵方程,对交替方向隐式迭代格式进行了改进,降低了程序实现难度.以Gauss消去法为例,对改进的交替方向隐式迭代格式的计算量进行估计,发现改进的交替方向隐... 本文以Poisson方程为例,在不对节点进行重新排列的前提下,通过求解较低维数的矩阵方程,对交替方向隐式迭代格式进行了改进,降低了程序实现难度.以Gauss消去法为例,对改进的交替方向隐式迭代格式的计算量进行估计,发现改进的交替方向隐式迭代格式大大减少了计算量,并进一步证明了改进的交替方向隐式迭代格式与经典的交替方向隐式迭代格式的等价性.数值算例验证了改进的交替方向隐式迭代格式与经典的交替方向隐式迭代格式的等价性和改进的交替方向隐式迭代格式在计算量等方面的优越性. 展开更多
关键词 poisson方程 交替方向隐式迭代格式 矩阵方程
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3-流形上的Poisson矩阵及其应用
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作者 李洪军 《数学学报(中文版)》 SCIE CSCD 北大核心 2004年第2期403-412,共10页
本文利用可定向3-流形切丛的平凡性,在3维几何上建立了一种整体标架法.对于3-流形上任一整体切标架,定义了一个Poisson矩阵,并给出:Poisson矩阵在标架改变时的变化规律.以Poisson矩阵为原始数据,计算了相应Riemannian度量各种曲率的具... 本文利用可定向3-流形切丛的平凡性,在3维几何上建立了一种整体标架法.对于3-流形上任一整体切标架,定义了一个Poisson矩阵,并给出:Poisson矩阵在标架改变时的变化规律.以Poisson矩阵为原始数据,计算了相应Riemannian度量各种曲率的具体表达式.对于具有常值Poisson矩阵的一类3-流形,这个方法被用来讨论它们的拓扑结构.它们基本上都是3维李群在其离散子群左平移作用下的商空间. 展开更多
关键词 整体标架 poisson矩阵 曲率 齐性空间
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