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Majorana's stellar representation for the quantum geometric tensor of symmetric states
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作者 Xingyu Zhang Jiancheng Pei +1 位作者 Libin Fu Xiaoguang Wang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2022年第6期31-38,共8页
Majorana's stellar representation provides an intuitive picture in which quantum states in highdimensional Hilbert space can be observed using the trajectory of Majorana stars.We consider the Majorana's stella... Majorana's stellar representation provides an intuitive picture in which quantum states in highdimensional Hilbert space can be observed using the trajectory of Majorana stars.We consider the Majorana's stellar representation of the quantum geometric tensor for a spin state up to spin-3/2.The real and imaginary parts of the quantum geometric tensor,corresponding to the quantum metric tensor and Berry curvature,are therefore obtained in terms of the Majorana stars.Moreover,we work out the expressions of quantum geometric tensor for arbitrary spin in some important cases.Our results will benefit the comprehension of the quantum geometric tensor and provide interesting relations between the quantum geometric tensor and Majorana's stars. 展开更多
关键词 quantum geometric tensor Berry curvature quantum metric tensor Majorana's stellar representation
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Gauge Invariance, the Quantum Metric Tensor and the Quantum Fidelity
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作者 J. Alvarez-Jiménez Jose David Vergara 《Journal of Modern Physics》 2016年第13期1627-1634,共9页
The quantum metric tensor was introduced for defining the distance in the parameter space of a system. However, it is also useful for other purposes, like predicting quantum phase transitions. Due to the physical info... The quantum metric tensor was introduced for defining the distance in the parameter space of a system. However, it is also useful for other purposes, like predicting quantum phase transitions. Due to the physical information this tensor provides, its gauge independence sounds reasonable. Moreover, its original construction was made by looking for this gauge independence. The aim of this paper, however, is to prove that the quantum metric tensor does depend on the gauge. In addition, a real gauge invariant quantum metric tensor is introduced. A related concept is the quantum fidelity, which is also shown to depend on the gauge in this paper. The gauge dependences are explicitly shown by computing the quantum metric tensor and the quantum fidelity of the Landau problem in different gauges. Then, a real gauge independent metric tensor is proposed and computed for the same Landau problem. Since the gauge dependences have not been observed before, the results of this paper might lead to a new study of topics that are believed to be completely understood. 展开更多
关键词 Landau problem Quantum metric tensor Gauge Dependence Quantum Fidelity
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The Small Deformation Strain Tensor as a Fundamental Metric Tensor
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作者 Angel Fierros Palacios 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第1期35-47,共13页
In the general theory of relativity, the fundamental metric tensor plays a special role, which has its physical basis in the peculiar aspects of gravitation. The fundamental property of gravitational fields provides t... In the general theory of relativity, the fundamental metric tensor plays a special role, which has its physical basis in the peculiar aspects of gravitation. The fundamental property of gravitational fields provides the possibility of establishing an analogy between the motion in a gravitational field and the motion in any external field considered as a noninertial system of reference. Thus, the properties of the motion in a noninertial frame are the same as those in an inertial system in the presence of a gravitational field. In other words, a noninertial frame of reference is equivalent to a certain gravitational field. This is known as the principle of equivalence. From the mathematical viewpoint, the same special role can be played by the small deformation strain tensor, which describes the geometrical properties of any region deformed because of the effect of some external agent. It can be proved that, from that tensor, all the mathematical structures needed in the general theory of relativity can be constructed. 展开更多
关键词 The SMALL DEFORMATION STRAIN tensor The FUNDAMENTAL metric tensor
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Restricted Gröbner Basis Theory for Normalization of Indexed Differential Riemann Metric Tensor Polynomials
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作者 LIU Jiang WANG Tao +3 位作者 HOU Pingjing NI Feng ZHU Kun ZHANG Leyi 《Journal of Systems Science & Complexity》 2025年第3期1370-1387,共18页
Riemman metric tensor(Rmt)plays a significant role in deducing basic formulas and equations arising in differential geometry and(pseudo-)Riemannian manifolds.It is a fundamental and challenging problem to determine th... Riemman metric tensor(Rmt)plays a significant role in deducing basic formulas and equations arising in differential geometry and(pseudo-)Riemannian manifolds.It is a fundamental and challenging problem to determine the equivalence of indexed differential Rmt polynomials.This paper solves the problem by extending Gröbner basis theory and the previous work on the computational theory for indexed differentials.L-expansion of an indexed differential Rmt polynomial is defined.Then a decomposed form of the Gröbner basis of defining syzygies of the polynomial ring is presented,based on a partition of elementary indexed monomials.Meanwhile,the upper bound of the dummy index numbers of sim-monomials of the elements in each disjoint elementary indexed monomial subset is found.Finally,a DST-fundamental restricted ring is constructed,and the canonical form of a polynomial is confirmed to be the normal form with respect to the Gröbner basis in the DST-fundamental restricted ring. 展开更多
关键词 Canonical form Einstein summation convention Gröbner basis Riemann metric tensor
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Recovery of Immersions from Their Metric Tensors and Nonlinear Korn Inequalities:A Brief Survey
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作者 Philippe G.CIARLET Cristinel MARDARE Sorin MARDARE 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2017年第1期253-280,共28页
The authors discuss the existence and uniqueness up to isometries of Enof immersions φ : Ω  R^n→ E^n with prescribed metric tensor field(g ij) : Ω→ S^n>, and discuss the continuity of the mapping(gij) →φ d... The authors discuss the existence and uniqueness up to isometries of Enof immersions φ : Ω  R^n→ E^n with prescribed metric tensor field(g ij) : Ω→ S^n>, and discuss the continuity of the mapping(gij) →φ defined in this fashion with respect to various topologies. In particular, the case where the function spaces have little regularity is considered. How, in some cases, the continuity of the mapping(gij) →φ can be obtained by means of nonlinear Korn inequalities is shown. 展开更多
关键词 Isometric immersions Nonlinear Korn inequalities metric tensor
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On Laguerre Isopararmetric Hypersurfaces in R^7 被引量:3
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作者 JI Xiu HU Chuan-feng 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第4期486-500,共15页
Let x : M → R n be an umbilical free hypersurface with non-zero principal curvatures, then x is associated with a Laguerre metric g, a Laguerre tensor L, a Laguerre form C, a Laguerre second fundamental form B, which... Let x : M → R n be an umbilical free hypersurface with non-zero principal curvatures, then x is associated with a Laguerre metric g, a Laguerre tensor L, a Laguerre form C, a Laguerre second fundamental form B, which are invariants of x under Laguerre transformation group. A classical theorem of Laguerre geometry states that M(n > 3) is characterized by g and B up to Laguerre equivalence. A Laguerre isopararmetric hypersurface is defined by satisfying the conditions that C = 0 and all the eigenvalues of B with respect to g are constant. It is easy to see that all Laguerre isopararmetric hypersurfaces are Dupin hypersurfaces. In this paper, we established a complete classification for all Laguerre isopararmetric hypersurfaces with three distinct principal curvatures in R7. 展开更多
关键词 laguerre metric laguerre form laguerre tensor laguerre second fundamental form laguerre isopararmetric hypersurface
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Note on Energy-Momentum Tensor for General Mixed Tensor-Spinor Fields
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作者 ZHANG Hong-Bao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期1007-1010,共4页
This note provides an explicit proof of the equivalence of Belinfante's energy-momentum tensor and metric energy-momentum tensor for general mixed tensor-spinor fields.
关键词 Belinfante's energy-momentum tensor metric energy-momentum tensor general mixed tensorspinor fields
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DEFORMING METRICS WITH POSITIVE CURVATURE BY A FULLY NONLINEAR FLOW
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作者 岳赟 盛为民 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期159-171,共13页
By studying a fully nonlinear flow deforming conformal metrics on a compact and connected manifold, we prove the long time existence and the exponential convergence of the solutions of the flow for any initial metric ... By studying a fully nonlinear flow deforming conformal metrics on a compact and connected manifold, we prove the long time existence and the exponential convergence of the solutions of the flow for any initial metric g0 with the Schouten tensor Ag0 ∈ Γk. 展开更多
关键词 Fully nonlinear flow conformal metrics Schouten tensor
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Plane Symmetric Solutions to the Nonlinear Spinor Field Equations in General Relativity Theory 被引量:5
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作者 A. Adomou Jonas Edou Siaka Massou 《Journal of Modern Physics》 2019年第10期1222-1234,共13页
We have obtained exact static plane-symmetric solutions to the spinor field equations with nonlinear terms which are arbitrary functions of invariant , taking into account their own gravitational field. It is shown th... We have obtained exact static plane-symmetric solutions to the spinor field equations with nonlinear terms which are arbitrary functions of invariant , taking into account their own gravitational field. It is shown that the initial set of the Einstein and spinor field equations with a power-law nonlinearity have regular solutions with a localized energy density of the spinor field only if m=0 (m is the mass parameter in the spinor field equations). Equations with power and polynomial nonlinearities are studied in detail. In this case, a soliton-like configuration has negative energy. We have also obtained exact static plane-symmetric solutions to the above spinor field equations in flat space-time. It is proved that in this case soliton-like solutions are absent. 展开更多
关键词 LAGRANGIAN Static Plane-Symmetric metric Field EQUATIONS ENERGY-MOMENTUM tensor Charge Density Current Vector SOLITON-LIKE Solution
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Orbits of Material Bodies in Complex TOUGMA’s Metric
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作者 Jean Luc Wendkouni Tougma 《Open Journal of Applied Sciences》 2023年第8期1310-1318,共9页
Einstein’s General relativity theory and Quantum physics are the main pillars for explaining most modern physics. Obtaining these theories relation between them remains a theoretical physics main question. In the las... Einstein’s General relativity theory and Quantum physics are the main pillars for explaining most modern physics. Obtaining these theories relation between them remains a theoretical physics main question. In the last most decades, works are leading to new physical ideas and mathematical tools broad range. In recent years TOUGMA’s equation is established and solved, and one of these solutions, mostly a real solution is studied in our last article. In this work, complex TOUGMA’s metric is studied, such as the physics concepts implied by this metric, mainly material bodies geodesics orbits. We studied the fact material bodies’ orbits and their limits. This study of the underlying principles and various phenomena in universe are interconnected logic leading to new technologies development such as news engines and telecommunication networks. The applications of this study are exceptionally wide such as Astrophysics, cosmology, Quantum gravity, Quantum Mechanics and Multiverse. Mostly this study allows us to know the behaviors of matter in the quantum relativity universe. Universe. 展开更多
关键词 Ricci tensor TOUGMA’s Complex metric Quantum Relativity
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Study of Complex TOUGMA’s Metric
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作者 Jean Luc Wendkouni Tougma 《Open Journal of Applied Sciences》 2023年第7期1005-1011,共7页
General relativity of Einstein’s theory and Quantum physics theory are excellent pillars that explain much modern physics. Understanding the relation between these theories is still a theoretical physics central open... General relativity of Einstein’s theory and Quantum physics theory are excellent pillars that explain much modern physics. Understanding the relation between these theories is still a theoretical physics central open question. Over last several decades, works in this direction have led to new physical ideas and mathematical tools broad range. In recent years TOUGMA’s equation is established and solved, one of its solutions such as a real solution is studied in our last article. In this paper, complex TOUGMA’s metric is studied, particularly the physics concepts that this metric implies such as light geodesic and metric’s impacts at r = 0. The first time, we studied the fact of r = 0 and its limits, secondly, we consider a zero length light geodesic is a geodesic and ended by studying it mathematically. These underlying principles study, those various phenomena in universe are interconnected logic leading to develop new technologies for example: news engines, telecommunication networks. This study’s applications are exceptionally wide such as Astrophysics, cosmology, Quantum gravity, Quantum Mechanics, Multiverse. Mostly this study lets us to know the quantum relativity universe behaviors. 展开更多
关键词 Complex metric of TOUGMA Quantum Relativity Ricci tensor
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New Way to Calculate Ricci Tensor and Ricci Scalar
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作者 Abed El Karim S. Abou Layla 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第3期850-867,共18页
In the theory of general relativity, the finding of the Einstein Field Equation happens in a complex mathematical operation, a process we don’t need any more. Through a new theory in vector analysis, we’ll see that ... In the theory of general relativity, the finding of the Einstein Field Equation happens in a complex mathematical operation, a process we don’t need any more. Through a new theory in vector analysis, we’ll see that we can calculate the components of the Ricci tensor, Ricci scalar, and Einstein Field Equation directly in an easy way without the need to use general relativity theory hypotheses, principles, and symbols. Formulating the general relativity theory through another theory will make it easier to understand this relativity theory and will help combining it with electromagnetic theory and quantum mechanics easily. 展开更多
关键词 General Relativity RICCI tensor RICCI SCALAR EINSTEIN Field Equation Stress-Energy tensor Robertson-Walker metric SCHWARZSCHILD metric
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A Classification of 3-dimensional Paracontact Metric Manifolds with φl=lφ
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作者 Quanxiang PAN Ximin LIU 《Journal of Mathematical Research with Applications》 CSCD 2018年第5期509-522,共14页
Let M;be a 3-dimensional paracontact metric manifold. Firstly, a classification of M;satisfying φQ = Qφ is given. Secondly, manifold M;satisfying φl = lφ and having η-parallel Ricci tensor or cyclic η-parallel R... Let M;be a 3-dimensional paracontact metric manifold. Firstly, a classification of M;satisfying φQ = Qφ is given. Secondly, manifold M;satisfying φl = lφ and having η-parallel Ricci tensor or cyclic η-parallel Ricci tensor is studied. 展开更多
关键词 paracontact metric manifold para-Sasakian manifold η-parallel Ricci tensor cyclic η-parallel Ricci tensor
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Nonlinear Spinor Field Equations in Gravitational Theory: Spherical Symmetric Soliton-Like Solutions 被引量:2
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作者 V. Adanhounme A. Adomou +1 位作者 F. P. Codo M. N. Hounkonnou 《Journal of Modern Physics》 2012年第9期935-942,共8页
This paper deals with an extension of a previous work [Gravitation & Cosmology, Vol. 4, 1998, pp 107-113] to exact spherical symmetric solutions to the spinor field equations with nonlinear terms which are arbitra... This paper deals with an extension of a previous work [Gravitation & Cosmology, Vol. 4, 1998, pp 107-113] to exact spherical symmetric solutions to the spinor field equations with nonlinear terms which are arbitrary functions of S=ψψ, taking into account their own gravitational field. Equations with power and polynomial nonlinearities are studied in detail. It is shown that the initial set of the Einstein and spinor field equations with a power nonlinearity has regular solutions with spinor field localized energy and charge densities. The total energy and charge are finite. Besides, exact solutions, including soliton-like solutions, to the spinor field equations are also obtained in flat space-time. 展开更多
关键词 Lagrangian Static SPHERICAL SYMmetric metric Field EQUATIONS EINSTEIN EQUATIONS Dirac Equation ENERGY-MOMENTUM tensor Charge Density Current Vector SOLITON-LIKE Solution
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面向弥散张量图像的鲁棒可逆水印算法
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作者 李丹丹 李智 +1 位作者 郑龙 张丽 《计算机工程》 北大核心 2025年第5期279-287,共9页
弥散张量成像(DTI)是一种常用的核磁共振成像技术,为了对弥散张量图像进行版权保护,同时保证弥散张量数据的完整性,提出一种基于黎曼度量的两阶段鲁棒可逆水印算法。为了避免常规欧几里得运算在张量空间中的误差,通过对数-欧几里得变换... 弥散张量成像(DTI)是一种常用的核磁共振成像技术,为了对弥散张量图像进行版权保护,同时保证弥散张量数据的完整性,提出一种基于黎曼度量的两阶段鲁棒可逆水印算法。为了避免常规欧几里得运算在张量空间中的误差,通过对数-欧几里得变换,将弥散张量从流形空间映射到对数-欧几里得空间,利用深度学习模型提取弥散张量图像的特征并嵌入水印信息。然后,结合可逆水印算法,在嵌入鲁棒水印后恢复出高质量的弥散张量图像。实验结果表明,该算法能够抵御裁剪、旋转、高斯噪声等攻击,且算法恢复出的弥散张量误差不超过2×10^(-8),峰值信噪比(PSNR)相较于VSTNet算法提高了21%。 展开更多
关键词 鲁棒水印 可逆水印 弥散张量图像 黎曼度量 深度学习
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基于黎曼度量的复杂参数曲面有限元网格生成方法 被引量:20
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作者 关振群 单菊林 顾元宪 《计算机学报》 EI CSCD 北大核心 2006年第10期1823-1833,共11页
给出了三维空间的黎曼度量和曲面自身的黎曼度量相结合的三维复杂参数曲面自适应网格生成的改进波前推进算法.详细阐述了曲面参数域上任意一点的黎曼度量的计算和插值方法;采用可细化的栅格作为背景网格,在降低了程序实现的难度的同时... 给出了三维空间的黎曼度量和曲面自身的黎曼度量相结合的三维复杂参数曲面自适应网格生成的改进波前推进算法.详细阐述了曲面参数域上任意一点的黎曼度量的计算和插值方法;采用可细化的栅格作为背景网格,在降低了程序实现的难度的同时提高了网格生成的速度;提出按层推进和按最短边推进相结合的方法,在保证边界网格质量的同时,提高曲面内部网格的质量.三维自适应黎曼度量的引入,提高了算法剖分复杂曲面的自适应性.算例表明,该算法对复杂曲面能够生成高质量的网格,而且整个算法具有很好的时间特性和可靠性. 展开更多
关键词 曲面网格生成 黎曼度量 映射法 波前推进算法 有限元
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张量值图像插值方法综述 被引量:4
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作者 邵宇 刘莹 孙富春 《中国图象图形学报》 CSCD 北大核心 2012年第10期1197-1205,共9页
在图像处理和计算机视觉的许多任务中,经常需要对图像进行插值从而得到像素点之间的信息。标量值图像的插值方法已经得到充分的发展,但张量值图像的插值方法还没有深刻的发展和认识。通过对比较零散的张量值图像插值方法的研究现状进行... 在图像处理和计算机视觉的许多任务中,经常需要对图像进行插值从而得到像素点之间的信息。标量值图像的插值方法已经得到充分的发展,但张量值图像的插值方法还没有深刻的发展和认识。通过对比较零散的张量值图像插值方法的研究现状进行了系统综述,从数学理论框架的角度出发,将现有的张量值图像插值方法进行全面分析和分类,指出欧氏理论框架计算张量会带来的问题,梳理从欧氏框架到黎曼度量框架的研究脉络,并比较了张量值图像插值方法的评价指标。最后,给出了张量值图像插值方法未来研究方向的建议。 展开更多
关键词 张量值图像 插值方法 黎曼度量框架 张量分量
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采用GPS观测值进行三维形变分析的构想 被引量:3
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作者 刘序俨 梁全强 +1 位作者 黄声明 丁学仁 《大地测量与地球动力学》 CSCD 北大核心 2006年第1期92-96,共5页
在已知地表度量张量的基础上,给出了根据测站的GPS复测值计算地表形变张量、主方向、线应变、面应变、高斯曲率与平均曲率的有关公式,并着重对地表的内蕴与外蕴形变概念作了阐述,最后指出利用地表内蕴与外蕴形变量能较好地描述地表的三... 在已知地表度量张量的基础上,给出了根据测站的GPS复测值计算地表形变张量、主方向、线应变、面应变、高斯曲率与平均曲率的有关公式,并着重对地表的内蕴与外蕴形变概念作了阐述,最后指出利用地表内蕴与外蕴形变量能较好地描述地表的三维形变。 展开更多
关键词 GPS观测值 度量张量 内蕴与外蕴形变 三维形变 分析流程
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Beltrami流及其在图像去噪中的应用 被引量:3
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作者 王泽龙 朱炬波 《国防科技大学学报》 EI CAS CSCD 北大核心 2012年第5期137-141,共5页
偏微分方程是图像处理主要的方法之一,一般通过其对应的变分模型给出方程的意义,并依此设计优化原偏微分方程以取得最佳的处理效果。针对图像去噪问题,基于经典的Beltrami几何流方法提出了图像流形上一种新的度量张量模型,具有该度量模... 偏微分方程是图像处理主要的方法之一,一般通过其对应的变分模型给出方程的意义,并依此设计优化原偏微分方程以取得最佳的处理效果。针对图像去噪问题,基于经典的Beltrami几何流方法提出了图像流形上一种新的度量张量模型,具有该度量模型的Beltrami流具有清晰的几何意义,并依此提出了该度量模型中参数的优化选择方法。同时,该模型为经典的偏微分方程去噪方法提供了统一框架,且参数的优化选择使得Beltrami流在平滑噪声与边缘保持方面取得了良好的平衡。实验表明该方法提高了图像去噪效果,尤其是对于边缘丰富的图像效果更加明显。 展开更多
关键词 Beltrami流 度量张量 图像去噪 边缘增强 相关增强
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Fast Texture Segmentation Based on Semi-Local Region Descriptor and Active Contour 被引量:10
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作者 Nawal Houhou Jean-Philippe Thiran Xavier Bresson 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第4期445-468,共24页
In this paper, we present an efficient approach for unsupervised segmentation of natural and textural images based on the extraction of image features and a fast active contour segmentation model. We address the probl... In this paper, we present an efficient approach for unsupervised segmentation of natural and textural images based on the extraction of image features and a fast active contour segmentation model. We address the problem of textures where neither the gray-level information nor the boundary information is adequate for object extraction. This is often the case of natural images composed of both homogeneous and textured regions. Because these images cannot be in general directly processed by the gray-level information, we propose a new texture descriptor which intrinsically defines the geometry of textures using semi-local image information and tools from differential geometry. Then, we use the popular Kullback-Leibler distance to design an active contour model which distinguishes the background and textures of interest. The existence of a minimizing solution to the proposed segmentation model is proven. Finally, a texture segmentation algorithm based on the Split-Bregrnan method is introduced to extract meaningful objects in a fast way. Promising synthetic and real-world results for gray-scale and color images are presented. 展开更多
关键词 Semi-local image information Beltrami framework metric tensor active contour Kullback-Leibler distance split-Bregman method.
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