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切空间的相关文献在1981年到2022年内共计95篇,主要集中在自动化技术、计算机技术、数学、中国文学 等领域,其中期刊论文72篇、会议论文1篇、专利文献671801篇;相关期刊62种,包括大庆社会科学、现代商业银行、中国科技奖励等; 相关会议1种,包括2005年中国智能自动化会议(ICAC'2005)等;切空间的相关文献由157位作者贡献,包括高小方、梁吉业、于雪莲等。

切空间—发文量

期刊论文>

论文:72 占比:0.01%

会议论文>

论文:1 占比:0.00%

专利文献>

论文:671801 占比:99.99%

总计:671874篇

切空间—发文趋势图

切空间

-研究学者

  • 高小方
  • 梁吉业
  • 于雪莲
  • 周云
  • 孙雯
  • 李跃明
  • 洪留荣
  • 葛方振
  • 马争鸣
  • F·思科内博格
  • 期刊论文
  • 会议论文
  • 专利文献

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    • 高小方; 刘杰飞; 梁吉业
    • 摘要: 流形学习已经成为机器学习与数据挖掘领域的一个重要的研究课题.经典的流形学习算法总假设所研究的高维数据存在于同一个单流形上,然而现实世界中的数据往往位于不同的流形且交叉重叠.当前的流形学习算法并不能有效应用于这种高维多流形数据.基于MPPCA模型提出一种面向相交多流形数据的识别算法D-MPPCA.该算法首先通过动态邻域算法计算出每个样本点的近邻关系和切空间,然后通过MPPCA模型将相交多流形数据分解成若干"不相交块",最后通过切空间扩展分解和识别多流形数据.实验结果表明,该算法能有效地应用于人工数据和实际的高维图像数据,相较于其他算法极大的提高了子流形识别精度.
    • 摘要: 对于喜欢自然科学的孩子,宇宙就是一个充满了神秘和未知的世界,似乎承载着他们对于自然的无限想象。“宇”指的是一切空间,包括东南西北中一切地点,是无边无际的;“宙”指一切时间,包括过去、现在、未来,是无始无终的。
    • 刘树勇; 位秀雷; 方远; 杨庆超
    • 摘要: 针对Lyapunov指数计算过程中,邻近点对演化难以有效刻画混沌轨道在相空间不同方向的动态特性问题,本文研究了混沌重构相空间中映射矩阵的构造方法,推导了混沌振动实测时间序列重构相空间中Lyapunov特征指数演化矩阵算法表达式,分析了轨道演化过程中切空间级联矩阵对参考点邻域的拉伸折叠作用,揭示其特征向量方向是邻域变形的方向、奇异值大小对应特征方向上邻域拉伸和压缩的大小.构造了包含映射值域和定义域的增广矩阵,通过微扰法分析了计算过程的误差.计算结果表明,应用重构演化矩阵算法能够有效提取混沌时间序列最大Lyapunov指数.设计了非线性混沌振动实验装置,证实了该方法的有效性.%The reconstruction map matrix of chaotic phase space is studied since the dynamical characteristics of the chaotic orbit at different directions are discovered by the nearest orbit ineffectively, and the formulation of Lyapunov exponent based on evolution matrices in reconstructed phase space is derived. It explains that in the process of orbit e-volution, the stretch and fold of the neighbor is the rotation operation of the cascade matrices and the fluctuation of the singular value of the reconstructed tangent space matrices. The SVD matrix of the reconstructed tangent space plays important role on the system dynamical behavior characteristic. The eigenvector direction is the deformation di-rection of the neighbor, and the stretch extent corresponds to the eigenvalue. The augmented matrix including range and definition domains is constructed, and the computation error is analyzed with perturbation. Numerical results show that the presented algorithm is useful to extract the maximal Lyapunov exponent of the chaotic time series. The experi-mental rig is designed and the Lyapunov exponent of the measured signal is computed with the method effectively.
    • 刘薇; 陈雷霆
    • 摘要: 微分同胚是一种光滑可逆的变换,在MRI图像配准中可以保证图像形变后的拓扑结构保持不变,同时避免出现不合理的物理现象.为了在空间变换中获得更合理的同胚映射,高维空间中数据的非线性结构被考虑,基于流形学习方法提出一种自适应切空间的MRI图像配准算法.首先,把MRI数据构造成对称正定(SPD)的协方差矩阵,然后形成李群;接着,利用样本点邻域的局部切空间来表示李群的几何结构的非线性;接下来,在流形上用自适应邻域选择的方法形成的线性子空间去逼近局部切空间,提高切空间的局部线性化程度,从而最大限度地保留流形的局部非线性结构,得到最优的同胚映射.仿真数据和临床数据的实验结果显示,与传统的非参数微分同胚配准算法相比,该算法在高维稠密形变场上获得更高的拓扑保持度,最终提高图像配准精度.%The diffeomorphism is a differential transformation with smooth and invertible properties,which leading to topology preservation between anatomic individuals while avoiding physically implausible phenomena during MRI image registration.In order to yield a more plausible diffeomorphism for spatial transformation,nonlinear structure of high-dimensional data was considered,and an MRI image registration using manifold learning based on adaptive tangent space was put forward.Firstly,Symmetric Positive Definite (SPD) covariance matrices were constructed by voxels from an MRI image,then to form a Lie group manifold.Secondly,tangent space on the Lie group was used to locally approximate nonlinear structure of the Lie group manifold.Thirdly,the local linear approximation was adaptively optimized by selecting appropriate neighborhoods for each sample voxel,therefore the linearization degree of tangent space was improved,the local nonlinearization structure of manifold was highly preserved,and the best optimal diffeomorphism could be obtained.Numerical comparative experiments were conducted on both synthetic data and clinical data.Experimental results show that compared with the existing algorithm,the proposed algorithm obtains a higher degree of topology preservation on a dense high-dimensional deformation field,and finally improves the registration accuracy.
    • 高小方; 刘杰飞
    • 摘要: 流形学习是机器学习与数据挖掘领域的一个重要研究方向.其经典算法总是假设高维数据批量存在于单一流形,且不能有效处理增量式出现的高维多流形数据.针对等维独立多流形提出一种增量学习算法IMM-ISOMAP.首先在对新样本增量地更新动态邻域时,仅修改关键路径,避免重新计算全部邻域关系,以提高算法整体效率.然后通过扩展切空间的方法将新样本依次划分到各子流形,实现新样本的增量式分类算法.最后对各子流形计算低维嵌入并进行合并.实验结果表明,该算法可以有效地应用于人造多流形数据和实际得多流形图像数据.%Manifold learning is an important research issne in the fields of machine learning and data mining.The classical algorithms always assume that the high dimensional batched data exist in a single manifold,and can not effectively deal with the high dimensional multi-manifold data.We propose an incremental learning algorithm IMM-ISOMAP for equal dimension independent multi-manifolds.The algorithm computes the dynamic neighborhood of the new sample,and then divides the new samples into sub-manifolds by extending the tangent space.Finally it realizes the classification of the new samples and calculates the final low dimensional embedding.The experimental results show that the proposed algorithm can be effectively applied to artificial data and real image data.
    • 苏丹; 刘恒兴
    • 摘要: 本文研究了光滑映射芽在RN作用下的轨道切空间的问题.利用乘积积分理论的方法,获得了光滑映射芽关于右等价群的一类子群RN的无限决定性的结果,推广了光滑映射芽是RN-有限决定的结果.%In this paper, the tangent space to the orbit of smooth map-germs under the action of RN is investigated. By produce integral theory, the infinite determinacy of smooth map-germs relative to a subgroup RN of right equivalent group is obtained, and the necessary and sufficient conditions for a smooth map-germ to be finitely RN-determined are extended.
    • 孙雯; 洪留荣; 葛方振
    • 摘要: Aiming at the problem of perspective distortion of image , a new method based on the new line detec-tion algorithm and the improved perspective transformation method is proposed to correct distorted image . Through the new line detection algorithm-TSAP, we can get the boundary line and the vertex position , so as to realize the linear detection .Using the improved control point policy to determine control point and perspective transformation formula , we can correct and normalize the distorted images .MATLAB simulation results show that the proposed method is of low computation , high accuracy and high fault tolerance .%针对图像的透视畸变问题,提出一种新的直线检测算法和改进的透视变换方法相结合的方法,实现对畸变图像的校正.通过新的直线检测算法—TSAP,得到边界直线和顶点位置,从而实现直线探测.使用改进的控制点策略确定控制点,利用透视变换公式,实现对畸变图像的校正和归一化.MATLAB仿真实验结果表明,该方法计算量小,精度高,容错性高.
    • 孙雯; 洪留荣; 葛方振
    • 摘要: In order to realize the rapid detection of the edge beeline of the solar panel,we propose a new pro⁃jection method based on tangent space,which can detect the edge line of the solar panel.We can get the edge information by the pretreatment,then transform the edge feature to the tangent plane representation.In tangent space,line is expressed as a horizontal line,and the angle of the horizontal line is the same as the straight line.The points on the horizontal line aggregates,resulting in a peak point after the angle projection. The peak point represents a beeline.So we realize the positioning of the edge beeline of the solar panel.The method is fast,anti noise ability is strong,and the accuracy can reach 97%.%为实现对太阳能电池板边缘直线的快速检测,文章提出基于切空间的角度投影方法。对太阳能电池板进行预处理,得到边缘信息,将其边缘特征进行切平面表示。在切平面内,直线表示成一条水平线,且该水平线的角度为直线的偏转角度。对切空间特征进行角度方向投影之后,该水平线上的点大量聚集,产生一个峰值点,该峰值点对应于原始直线。由此实现了对太阳能电池板边缘直线的定位。实验表明该方法速度快,抗噪能力强,精确度可达到97%。
    • 孙雯; 洪留荣; 葛方振
    • 摘要: 为实现对太阳能电池板边缘直线的快速检测,文章提出基于切空间的角度投影方法。对太阳能电池板进行预处理,得到边缘信息,将其边缘特征进行切平面表示。在切平面内,直线表示成一条水平线,且该水平线的角度为直线的偏转角度。对切空间特征进行角度方向投影之后,该水平线上的点大量聚集,产生一个峰值点,该峰值点对应于原始直线。由此实现了对太阳能电池板边缘直线的定位。实验表明该方法速度快,抗噪能力强,精确度可达到97%。
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