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Seismic data reconstruction based on low dimensional manifold model 被引量:1
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作者 Nan-Ying Lan Fan-Chang Zhang Xing-Yao Yin 《Petroleum Science》 SCIE CAS CSCD 2022年第2期518-533,共16页
Seismic data reconstruction is an essential and yet fundamental step in seismic data processing workflow,which is of profound significance to improve migration imaging quality,multiple suppression effect,and seismic i... Seismic data reconstruction is an essential and yet fundamental step in seismic data processing workflow,which is of profound significance to improve migration imaging quality,multiple suppression effect,and seismic inversion accuracy.Regularization methods play a central role in solving the underdetermined inverse problem of seismic data reconstruction.In this paper,a novel regularization approach is proposed,the low dimensional manifold model(LDMM),for reconstructing the missing seismic data.Our work relies on the fact that seismic patches always occupy a low dimensional manifold.Specifically,we exploit the dimension of the seismic patches manifold as a regularization term in the reconstruction problem,and reconstruct the missing seismic data by enforcing low dimensionality on this manifold.The crucial procedure of the proposed method is to solve the dimension of the patches manifold.Toward this,we adopt an efficient dimensionality calculation method based on low-rank approximation,which provides a reliable safeguard to enforce the constraints in the reconstruction process.Numerical experiments performed on synthetic and field seismic data demonstrate that,compared with the curvelet-based sparsity-promoting L1-norm minimization method and the multichannel singular spectrum analysis method,the proposed method obtains state-of-the-art reconstruction results. 展开更多
关键词 Seismic data reconstruction Low dimensional manifold model REGULARIZATION Low-rank approximation
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Principal Manifolds and Nonlinear Dimensionality Reduction via Tangent Space Alignment 被引量:73
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作者 张振跃 查宏远 《Journal of Shanghai University(English Edition)》 CAS 2004年第4期406-424,共19页
We present a new algorithm for manifold learning and nonlinear dimensionality reduction. Based on a set of unorganized data points sampled with noise from a parameterized manifold, the local geometry of the manifold i... We present a new algorithm for manifold learning and nonlinear dimensionality reduction. Based on a set of unorganized data points sampled with noise from a parameterized manifold, the local geometry of the manifold is learned by constructing an approximation for the tangent space at each point, and those tangent spaces are then aligned to give the global coordinates of the data points with respect to the underlying manifold. We also present an error analysis of our algorithm showing that reconstruction errors can be quite small in some cases. We illustrate our algorithm using curves and surfaces both in 2D/3D Euclidean spaces and higher dimensional Euclidean spaces. We also address several theoretical and algorithmic issues for further research and improvements. 展开更多
关键词 nonlinear dimensionality reduction principal manifold tangent space subspace alignment singular value decomposition.
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Retractions of One Dimensional Manifold 被引量:2
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作者 A. E. El-Ahmady Nashwa Salem Awyd Al-Hazmi 《Applied Mathematics》 2012年第10期1135-1143,共9页
Our aim in the present article is to introduce and study types of retraction of one dimensional manifold. New types of geodesics in one dimensional manifold are presented. The deformation retracts of one dimensional m... Our aim in the present article is to introduce and study types of retraction of one dimensional manifold. New types of geodesics in one dimensional manifold are presented. The deformation retracts of one dimensional manifold into itself and onto geodesics is deduced. Also, the isometric and topological folding in each case and the relation between the deformations retracts after and before folding has been obtained. New types of conditional folding are described. 展开更多
关键词 RETRACTIONS Deformation Retracts FOLDING One dimensionAL manifold
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THEORETICAL STUDY OF THREE-DIMENSIONAL NUMERICAL MANIFOLD METHOD
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作者 骆少明 张湘伟 +1 位作者 吕文阁 姜东茹 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第9期1126-1131,共6页
The three-dimensional numerical manifold method(NMM) is studied on the basis of two-dimensional numerical manifold method. The three-dimensional cover displacement function is studied. The mechanical analysis and Ha... The three-dimensional numerical manifold method(NMM) is studied on the basis of two-dimensional numerical manifold method. The three-dimensional cover displacement function is studied. The mechanical analysis and Hammer integral method of three-dimensional numerical manifold method are put forward. The stiffness matrix of three-dimensional manifold element is derived and the dissection rules are given. The theoretical system and the numerical realizing method of three-dimensional numerical manifold method are systematically studied. As an example, the cantilever with load on the end is calculated, and the results show that the precision and efficiency are agreeable. 展开更多
关键词 numerical manifold method three-dimensional analysis finite cover
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Semi-Supervised Dimensionality Reduction of Hyperspectral Image Based on Sparse Multi-Manifold Learning
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作者 Hong Huang Fulin Luo +1 位作者 Zezhong Ma Hailiang Feng 《Journal of Computer and Communications》 2015年第11期33-39,共7页
In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploit... In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploits both the labeled and unlabeled data to adaptively find neighbors of each sample from the same manifold by using an optimization program based on sparse representation, and naturally gives relative importance to the labeled ones through a graph-based methodology. Then it tries to extract discriminative features on each manifold such that the data points in the same manifold become closer. The effectiveness of the proposed multi-manifold learning algorithm is demonstrated and compared through experiments on a real hyperspectral images. 展开更多
关键词 HYPERSPECTRAL IMAGE Classification dimensionality Reduction Multiple manifoldS Structure SPARSE REPRESENTATION SEMI-SUPERVISED Learning
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HOLOMORPHIC MANIFOLDS ON LOCALLY CONVEX SPACES
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作者 Tsoy-Wo Ma 《Analysis in Theory and Applications》 2005年第4期339-358,共20页
Based on locally compact perturbations of the identity map similar to the Fredholm structures on real Banach manifolds, complex manifolds with inverse mapping theorem as part of the defintion are proposed. Standard to... Based on locally compact perturbations of the identity map similar to the Fredholm structures on real Banach manifolds, complex manifolds with inverse mapping theorem as part of the defintion are proposed. Standard topics including holomorphic maps, morphisms, derivatives, tangent bundles, product manifolds and submanifolds are presented. Although this framework is elementary, it lays the necessary foundation for all subsequent developments. 展开更多
关键词 Holomorphic manifolds infinite dimensional manifolds complex manifolds
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Implementation of Manifold Learning Algorithm Isometric Mapping
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作者 Huan Yang Haiming Li 《Journal of Computer and Communications》 2019年第12期11-19,共9页
In dealing with high-dimensional data, such as the global climate model, facial data analysis, human gene distribution and so on, the problem of dimensionality reduction is often encountered, that is, to find the low ... In dealing with high-dimensional data, such as the global climate model, facial data analysis, human gene distribution and so on, the problem of dimensionality reduction is often encountered, that is, to find the low dimensional structure hidden in high-dimensional data. Nonlinear dimensionality reduction facilitates the discovery of the intrinsic structure and relevance of the data and can make the high-dimensional data visible in the low dimension. The isometric mapping algorithm (Isomap) is an important algorithm for nonlinear dimensionality reduction, which originates from the traditional dimensionality reduction algorithm MDS. The MDS algorithm is based on maintaining the distance between the samples in the original space and the distance between the samples in the lower dimensional space;the distance used here is Euclidean distance, and the Isomap algorithm discards the Euclidean distance, and calculates the shortest path between samples by Floyd algorithm to approximate the geodesic distance along the manifold surface. Compared with the previous nonlinear dimensionality reduction algorithm, the Isomap algorithm can effectively compute a global optimal solution, and it can ensure that the data manifold converges to the real structure asymptotically. 展开更多
关键词 manifold NONLINEAR dimensionality REDUCTION ISOMAP ALGORITHM MDS ALGORITHM
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APPROXIMATE INERTIAL MANIFOLDS FOR THE SYSTEM OF THE J-J EQUATIONS
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作者 蔡日增 徐振源 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第4期341-349,共9页
In this paper foe Liapunov functionals has been constructed.the decay property of the high dimensional modes of the J-J equations in the Josephson junctions is obtained,and thus the approxtmate inertial manifolds are... In this paper foe Liapunov functionals has been constructed.the decay property of the high dimensional modes of the J-J equations in the Josephson junctions is obtained,and thus the approxtmate inertial manifolds are given. 展开更多
关键词 approximate inertial manifolds infinite dimensional dynamical Systems
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On Kirichenko Tensors of Nearly-Khlerian Manifolds
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作者 Mihail B.BANARU 《四川理工学院学报(自然科学版)》 CAS 2012年第4期1-5,共5页
A short description of structural and virtual Kirichenko tensors that form a complete system of first-order differential-geometrical invariants of an arbitrary almost Hermitian structure is given.A characterization of... A short description of structural and virtual Kirichenko tensors that form a complete system of first-order differential-geometrical invariants of an arbitrary almost Hermitian structure is given.A characterization of nearly-Khlerian structures in terms of Kirichenko tensors is also given. 展开更多
关键词 Kirichenko tensors Ricci tensor nearly-Khlerian manifold almost Hermitian manifold six-dimensional submanifolds of Cayley algebra
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Clustering Analysis of Stocks of CSI 300 Index Based on Manifold Learning
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作者 Ruiling Liu Hengjin Cai Cheng Luo 《Journal of Intelligent Learning Systems and Applications》 2012年第2期120-126,共7页
As an effective way in finding the underlying parameters of a high-dimension space, manifold learning is popular in nonlinear dimensionality reduction which makes high-dimensional data easily to be observed and analyz... As an effective way in finding the underlying parameters of a high-dimension space, manifold learning is popular in nonlinear dimensionality reduction which makes high-dimensional data easily to be observed and analyzed. In this paper, Isomap, one of the most famous manifold learning algorithms, is applied to process closing prices of stocks of CSI 300 index from September 2009 to October 2011. Results indicate that Isomap algorithm not only reduces dimensionality of stock data successfully, but also classifies most stocks according to their trends efficiently. 展开更多
关键词 manifold Learning ISOMAP Nonlinear dimensionality Reduction STOCK CLUSTERING
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The Boundary Layer Equations and a Dimensional Split Method for Navier-Stokes Equations in Exterior Domain of a Spheroid and Ellipsoid
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作者 Jian Su Hongzhou Fan +2 位作者 Weibing Feng Hao Chen Kaitai Li 《International Journal of Modern Nonlinear Theory and Application》 2015年第1期48-87,共40页
In this paper, the boundary layer equations (abbreviation BLE) for exterior flow around an obstacle are established using semi-geodesic coordinate system (S-coordinate) based on the curved two dimensional surface of t... In this paper, the boundary layer equations (abbreviation BLE) for exterior flow around an obstacle are established using semi-geodesic coordinate system (S-coordinate) based on the curved two dimensional surface of the obstacle. BLE are nonlinear partial differential equations on unknown normal viscous stress tensor and pressure on the obstacle and the existence of solution of BLE is proved. In addition a dimensional split method for dimensional three Navier-Stokes equations is established by applying several 2D-3C partial differential equations on two dimensional manifolds to approach 3D Navier-Stokes equations. The examples for the exterior flow around spheroid and ellipsoid are presents here. 展开更多
关键词 Boundary Layer EQUATIONS dimensionAL SPLIT METHOD Navier-Stokes EQUATIONS dimensionAL Two manifold
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WAVELET APPROXIMATE INERTIAL MANIFOLD AND NUMERICAL SOLUTION OF BURGERS' EQUATION
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作者 田立新 许伯强 刘曾荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第10期1140-1152,共13页
The existence of approximate inertial manifold Using wavelet to Burgers' equation, and numerical solution under multiresolution analysis with the low modes were studied. It is shown that the Burgers' equation ... The existence of approximate inertial manifold Using wavelet to Burgers' equation, and numerical solution under multiresolution analysis with the low modes were studied. It is shown that the Burgers' equation has a good localization property of the numerical solution distinguishably. 展开更多
关键词 WAVELET wavelet approximate inertial manifold (WAIM) wavelet Galerkin solution infinite dimensional dynamic system
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基于空间光谱联合的LPP算法
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作者 邹彦艳 田年年 《吉林大学学报(信息科学版)》 CAS 2024年第3期550-558,共9页
针对原始的流形学习算法仅利用其光谱特征而没有利用空间信息的问题,提出了基于监督的空谱联合的局部保持投影算法(SS-LPP:Spatial-Spectral Locality Preserving Projections)。该算法首先使用加权均值滤波算法对数据集进行滤波,将空... 针对原始的流形学习算法仅利用其光谱特征而没有利用空间信息的问题,提出了基于监督的空谱联合的局部保持投影算法(SS-LPP:Spatial-Spectral Locality Preserving Projections)。该算法首先使用加权均值滤波算法对数据集进行滤波,将空间信息与光谱信息进行融合并消除噪点的干扰,增加同类数据的相关性。然后利用标签集构造类内图和类间图,并通过其可有效提取鉴别特征和改善分类性能。在Salinas和PaviaU数据集上对该算法的有效性进行验证。实验结果表明,该算法能有效提取数据特征,并提高分类的准确性。 展开更多
关键词 流形学习 降维 高光谱遥感影像 特征提取
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结合双流形映射的不完备多标签学习
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作者 许智磊 黄睿 《计算机工程》 CAS CSCD 北大核心 2024年第4期104-112,共9页
在多标签学习中,有效利用标签相关性可以提高分类性能。然而,由于人工标注标签的主观性和实际应用中标签语义的相似性,通常只能观察到不完备的标签空间,导致标签相关性的估计不准确,使得算法性能下降。针对该问题,提出一种结合双流形映... 在多标签学习中,有效利用标签相关性可以提高分类性能。然而,由于人工标注标签的主观性和实际应用中标签语义的相似性,通常只能观察到不完备的标签空间,导致标签相关性的估计不准确,使得算法性能下降。针对该问题,提出一种结合双流形映射的不完备多标签学习(ML-DMM)算法。构造两种流形映射,一种是保留实例数据空间局部结构信息的特征流形映射,另一种是基于迭代学习得到的标签相关性的标签流形映射。首先通过拉普拉斯映射构造数据的低维流形,然后通过回归系数矩阵和标签相关性矩阵将初始特征空间和初始标签空间分别映射到该低维流形上,形成一种双流形映射结构来提升算法性能,最后利用迭代学习得到的回归系数矩阵进行多标签分类。在8个多标签数据集及3种标签缺失率情况下的对比实验结果表明,ML-DMM算法性能优于其他针对缺失标签的多标签分类算法。 展开更多
关键词 多标签学习 缺失标签 标签相关性 低维流形 双流形映射
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大型LNG船集管区平台结构参数化设计与计算分析
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作者 刘金鑫 陈鹏 +4 位作者 张鼎 张海瑛 邱伟强 刘晨霄 施海天 《舰船科学技术》 北大核心 2024年第12期60-63,共4页
为实现对大型LNG船集管区平台的高效与高质量设计,提出一种集管区平台的三维参数化设计方法,通过CATIA V6软件二次开发和知识工程模板,快速搭建平台的有限元模型和实体模型,并实现工程图出图;同时提出一种对大型LNG船集管区平台的加载方... 为实现对大型LNG船集管区平台的高效与高质量设计,提出一种集管区平台的三维参数化设计方法,通过CATIA V6软件二次开发和知识工程模板,快速搭建平台的有限元模型和实体模型,并实现工程图出图;同时提出一种对大型LNG船集管区平台的加载方式,利用有限元数值仿真技术对平台的强度进行计算校核。研究表明,采用该参数化设计方法较常规设计周期缩短了8天,提高了设计精度,加载方式可有效模拟平台的受力情况,为今后同类LNG集管区平台的设计提供一定参考。 展开更多
关键词 LNG船集管区平台 CATIA V6 三维参数化设计 知识工程 强度计算
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基于多尺度一维卷积神经网络的弯管冲蚀损伤智能检测方法
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作者 陈传智 李宁 +2 位作者 王畅 陈家梁 罗锦达 《科学技术与工程》 北大核心 2024年第5期1893-1899,共7页
针对高压管汇损伤需要提高检测效率和准确率的问题,提出一种基于多尺度一维卷积神经网络(multi-scale one-dimensional convolutional neural network,MS-1DCNN)的弯管冲蚀损伤智能检测新方法,即用多尺度卷积层代替传统的单一尺度卷积... 针对高压管汇损伤需要提高检测效率和准确率的问题,提出一种基于多尺度一维卷积神经网络(multi-scale one-dimensional convolutional neural network,MS-1DCNN)的弯管冲蚀损伤智能检测新方法,即用多尺度卷积层代替传统的单一尺度卷积层。在MS-1DCNN模型中,把通过模拟实验所得弯管冲蚀损伤原始时域信号作为多尺度一维卷积神经网络的输入,这样能解决传统方法依赖人工提取特征和专家知识的问题;然后,通过多尺度卷积层和池化层的交替连接对输入信号进行特征提取;最后,经由输出层输出弯管冲蚀损伤分类结果。模型试验结果表明:基于MS-1DCNN弯管冲蚀损伤检测方法可以有效检测出弯管冲蚀损伤,且平均检测准确率达到99.18%。研究可为高压管汇冲蚀损伤智能检测提供一种新思路。 展开更多
关键词 高压管汇 冲蚀损伤 一维卷积神经网络 多尺度 智能检测
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俯仰翼型流体动力学系统的稀疏建模与预测
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作者 王子豪 张桂勇 孙铁志 《力学学报》 EI CAS CSCD 北大核心 2024年第9期2533-2543,共11页
重点探讨了在低雷诺数和大攻角条件下,俯仰翼型复杂流体流动的非线性动力学特性.研究通过整合多个相互关联的变量,利用主成分分析(principal component analysis,PCA)和等距特征映射(isometric mapping,ISOMAP)降维技术,成功实现了对高... 重点探讨了在低雷诺数和大攻角条件下,俯仰翼型复杂流体流动的非线性动力学特性.研究通过整合多个相互关联的变量,利用主成分分析(principal component analysis,PCA)和等距特征映射(isometric mapping,ISOMAP)降维技术,成功实现了对高维流场数据的低维表达.其中,特别强调了ISOMAP在描述非线性流场特征方面的卓越性能,该算法具有更强的灵活性,能够有效处理高度非线性系统的复杂结构.在此基础上,研究进一步引入最小绝对收缩和选择算子(least absolute shrinkage and selection operator,LASSO)模型,构建了流场的常微分控制方程.这一模型通过自动检测和筛选非线性项,显著简化了流场的描述,提高了对多变量复杂关系的理解.最后,研究采用5(4)显式龙格-库塔方法,实现了对多变量非线性流体动力学的高精度快速预测.这项研究框架不仅突破了传统单一变量分析的局限性,还通过整合多维信息,全面揭示了流场的复杂特性.引入流形学习和稀疏建模等先进技术,展示了在高维非线性动力系统中的全面建模与精确预测的潜力.这一研究为应用科学和工程领域提供了重要的理论方法学进展,为深入理解和预测复杂流场中的非线性动态行为开辟了新的路径.这不仅为相关科学研究提供了强有力的工具,也为工程应用中的流体动力学问题提供了有效的解决方案. 展开更多
关键词 非线性 流形学习 低维流形 稀疏建模 流体动力学
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粒子群算法优化的广义回归神经网络求解流形学习样本外点问题
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作者 黄红兵 《乐山师范学院学报》 2024年第4期1-7,共7页
目前流形学习已成功应用于降维和数据可视化领域,但在监督分类中的应用效果并不理想,解决好样本外点问题对其应用效果至关重要。基于此,采用粒子群算法优化广义回归神经网络计算测试样本的低维嵌入,获得的结果可直接用于分类。借助粒子... 目前流形学习已成功应用于降维和数据可视化领域,但在监督分类中的应用效果并不理想,解决好样本外点问题对其应用效果至关重要。基于此,采用粒子群算法优化广义回归神经网络计算测试样本的低维嵌入,获得的结果可直接用于分类。借助粒子群算法的全局搜索能力对处理样本外点问题具有较好的预测性能;在使用糖尿病、虹膜和声呐三个公开数据集的实验中,粒子群算法优化广义回归神经网络的分类总体精度分别为77.63%、100%和88.89%,优于其他8种分类方法,表明该算法可行、有效;同时,该算法能显著降低数据复杂度,提高了预测、模式分类和机器学习的准确性。 展开更多
关键词 粒子群算法 广义回归神经网络 流形学习 数据降维 样本外点问题
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流形切割及有限元网格覆盖下的三维流形单元生成 被引量:18
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作者 李海枫 张国新 +1 位作者 石根华 彭校初 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2010年第4期731-742,共12页
三维流形单元生成和接触搜索算法问题是制约三维数值流形方法发展的瓶颈问题。系统详细地研究三维流形单元的生成方法,在前人工作基础上,采用三维有限元网格生成技术生成数学网格;通过块体数据结构、块体识别算法等方面的改进,将三维块... 三维流形单元生成和接触搜索算法问题是制约三维数值流形方法发展的瓶颈问题。系统详细地研究三维流形单元的生成方法,在前人工作基础上,采用三维有限元网格生成技术生成数学网格;通过块体数据结构、块体识别算法等方面的改进,将三维块体切割技术发展成流形切割技术,来解决流形块体生成问题;将石根华博士在二维NMM程序中采用的物理覆盖系统编码算法,扩展成三维流形编码算法,进而实现三维流形单元的生成。并在此基础上开发三维流形切割程序3D_MC.f90,可以实现四面体及六面体网格覆盖下任意形状三维流形单元的生成。通过几个例子可以看出,三维流形切割程序生成的流形块体形态、流形单元的节点与单元编码等均满足三维流形单元定义要求,从流形切割角度来看,说明此算法是正确的。 展开更多
关键词 数值分析 数值流形方法 三维流形单元 流形切割
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散乱数据点的增量快速曲面重建算法 被引量:70
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作者 王青 王融清 +1 位作者 鲍虎军 彭群生 《软件学报》 EI CSCD 北大核心 2000年第9期1221-1227,共7页
给出了一个新的散乱数据的曲面重建算法 .算法充分利用邻近点集反映出的局部拓扑和几何信息 ,基于二维 Delaunay三角剖分技术快速地实现每个数据点的局部拓扑重建 ,然后通过自动矫正局部数据点的非法连接关系 ,以增量扩张的方式把局部... 给出了一个新的散乱数据的曲面重建算法 .算法充分利用邻近点集反映出的局部拓扑和几何信息 ,基于二维 Delaunay三角剖分技术快速地实现每个数据点的局部拓扑重建 ,然后通过自动矫正局部数据点的非法连接关系 ,以增量扩张的方式把局部三角网拼接成一张标准的整体二维流形网格 .该算法在重建过程中能自动进行洞的检测 ,判断出散乱数据所蕴涵的开或闭的拓扑结构 .实验结果表明 ,该算法高效、稳定 ,可以快速地直接重构出任意拓扑结构的二维流形三角形网格 . 展开更多
关键词 曲面重建 散乱数据点 几何造型 CAD
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