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Generalized regular points of a C^1 map between Banach spaces
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作者 史平 马吉溥 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期148-150,共3页
Let f be a C^1 map between two Banach spaces E and F. It has been proved that the concept of generalized regular points of f, which is a generalization of the notion of regular points of f, has some crucial applicatio... Let f be a C^1 map between two Banach spaces E and F. It has been proved that the concept of generalized regular points of f, which is a generalization of the notion of regular points of f, has some crucial applications in nonlinearity and global analysis. We characterize the generalized regular points of f using the three integer-valued (or infinite) indices M(x0), Mc(x0) and Mr(x0) at x0 ∈ E generated by f and by analyzing generalized inverses of bounded linear operators on Banach spaces, that is, iff '(x0) has a generalized inverse in the Banach space B(E, F) of all bounded linear operators on E into F and at least one of the indices M(x0), Mc(x0) and Mr(x0) is finite, then xo is a generalized regular point off if and only if the multi-index (M(x), Me(x), Mr(x)) is continuous at X0. 展开更多
关键词 Banach space bounded linear operator generalized inverse index generalized regular point semi- Fredholm mao
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A remark on regular points of Ricci limit spaces 被引量:1
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作者 Lina CHEN 《Frontiers of Mathematics in China》 SCIE CSCD 2016年第1期21-26,共6页
Let Y be a Gromov-Hausdorff limit of complete Riemannian nmanifolds with Ricci curvature bounded from below. A point in Y is called k-regular, if its tangent is unique and is isometric to a k-dimensional Euclidean spa... Let Y be a Gromov-Hausdorff limit of complete Riemannian nmanifolds with Ricci curvature bounded from below. A point in Y is called k-regular, if its tangent is unique and is isometric to a k-dimensional Euclidean space. By Cheeger-Colding and Colding-Naber, there is k 〉 0 such that the set of all k-regular point :Rk has a full renormalized measure. An open problem is if Rl = 0 for all l 〈 k? The main result in this paper asserts that if R1 ≠ 0, then Y is a one-dimensional topological manifold. Our result improves Honda's result that under the assumption that 1 ≤ dimH(Y) 〈 2. 展开更多
关键词 Ricci curvature regular point Gromov-Hausdorff limit
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Regular-Singular Crossings on Nonlinear Systems with Turning Point
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作者 Zhang Hanlin (Beijing Polytechnic University) Zhang Heping (Beijing Electric Power College) 《Advances in Manufacturing》 SCIE CAS 1998年第3期21-23,共3页
We consider in this paper the boundary value problems of nonlinear systems the form εY″=F(t,Y,Y′,ε), -1<t<1, Y(-1,ε)=A(ε), Y(1,ε)=B(ε). Supoosing some or all of the components of F , that is, ... We consider in this paper the boundary value problems of nonlinear systems the form εY″=F(t,Y,Y′,ε), -1<t<1, Y(-1,ε)=A(ε), Y(1,ε)=B(ε). Supoosing some or all of the components of F , that is, f i satisfy 2 f y′ 2 i t =0 =0, we say that F possesses a generalized turning point at t =0. Our goal is to give sufficient conditions for the existence of solution of the problems and to study the asymptotic behavior of the solution when F possesses a generalized turning point at t =0. We mainly discuss regular singular crossings. 展开更多
关键词 turning point regular singular crossing differential inequality
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FIXED POINTS OF A PAIR OF ASYMPTOTICALLY REGULAR MAPPINGS 被引量:1
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作者 B. K. Sharma B. S. Thakur(School of Studies in Mathematics.Pt. Ravishankar Shukla University. Raipur-492010 India)(Received Nov. 20. 1996. Communicated by Ding Xieping) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第8期771-778,共8页
In this paper some theorems on fixed points of pair of asymptotically regularmappings in p-uniformly convex Banach space are proved For these mappings somefixed point theorems in a Hilbert space.in Lp spaces in Hardy ... In this paper some theorems on fixed points of pair of asymptotically regularmappings in p-uniformly convex Banach space are proved For these mappings somefixed point theorems in a Hilbert space.in Lp spaces in Hardy spaces Hp and in Sobolev spaces Hpk for 1<P<+∞ and K>0 are also established.Thus resultsof Gornicki Kruppel and others are extended. 展开更多
关键词 asymptotically regular mappings p-uniformly convex Banach space asymptotic center fixed points
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HAMILTON-JACOBI EQUATIONS FOR A REGULAR CONTROLLED HAMILTONIAN SYSTEM AND ITS REDUCED SYSTEMS 被引量:1
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作者 王红 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期855-906,共52页
In this paper,we give the geometric constraint conditions of a canonical symplectic form and regular reduced symplectic forms for the dynamical vector fields of a regular controlled Hamiltonian(RCH)system and its regu... In this paper,we give the geometric constraint conditions of a canonical symplectic form and regular reduced symplectic forms for the dynamical vector fields of a regular controlled Hamiltonian(RCH)system and its regular reduced systems,which are called the Type I and Type II Hamilton-Jacobi equations.First,we prove two types of Hamilton-Jacobi theorems for an RCH system on the cotangent bundle of a configuration manifold by using the canonical symplectic form and its dynamical vector field.Second,we generalize the above results for a regular reducible RCH system with symmetry and a momentum map,and derive precisely two types of Hamilton-Jacobi equations for the regular point reduced RCH system and the regular orbit reduced RCH system.Third,we prove that the RCH-equivalence for the RCH system,and the RpCH-equivalence and RoCH-equivalence for the regular reducible RCH systems with symmetries,leave the solutions of corresponding Hamilton-Jacobi equations invariant.Finally,as an application of the theoretical results,we show the Type I and Type II Hamilton-Jacobi equations for the Rp-reduced controlled rigid body-rotor system and the Rp-reduced controlled heavy top-rotor system on the generalizations of the rotation group SO(3)and the Euclidean group SE(3),respectively.This work reveals the deeply internal relationships of the geometrical structures of phase spaces,the dynamical vector fields and the controls of the RCH system. 展开更多
关键词 regular controlled Hamiltonian system Hamilton-Jacobi equation regular point reduction regular orbit reduction RCH-equivalence
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一种增密3D高斯的室内实景三维重建方法
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作者 黄道红 刘春玲 石磊 《计算机应用研究》 北大核心 2026年第2期626-632,共7页
针对复杂室内场景中经典三维重建方法存在细节表征不足、边缘模糊、混叠伪影等问题,提出一种基于三维高斯溅射(3DGS)的复杂室内场景三维重建算法。首先提出前置点云增密网络对运动结构恢复的稀疏点云进行增密补全,构建高分辨率的增强3D... 针对复杂室内场景中经典三维重建方法存在细节表征不足、边缘模糊、混叠伪影等问题,提出一种基于三维高斯溅射(3DGS)的复杂室内场景三维重建算法。首先提出前置点云增密网络对运动结构恢复的稀疏点云进行增密补全,构建高分辨率的增强3D高斯辐射场,提高对复杂场景细节部分的表征精度;随后引入场景的深度信息,设计了深度正则化损失函数,利用深度代价信息关联场景中不同深度的物体,解决结构尺度模糊问题;结合自适应密度控制策略动态优化辐射场参数,提高重建模型的精度和视觉效果。在tanks and temples和Mip-NeRF360数据集上的实验表明,该方法与传统3DGS相比,重建视图峰值信噪比分别提升了7.26%和5.03%,结构性相似和学习感知图像块相似度等指标均有改善,有效解决了三维数字图像重建中存在的精度不足和模糊混叠等问题,为室内设计、导航及数字化城市建设提供了技术支持。 展开更多
关键词 三维重建 三维高斯溅射 点云增密 深度正则化 自适应密度控制
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正规半距离空间中的Geraghty不动点定理
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作者 王鹏 贺飞 《纯粹数学与应用数学》 2026年第1期113-120,共8页
半距离空间是一类非常广泛的空间框架,本文在正规半距离空间建立Geraghty型压缩不动点定理.作为推论,可以推出距离空间和b-距离空间中的Geraghty不动点定理.
关键词 距离空间 b-距离空间 正规半距离空间 Geraghty不动点定理
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带有移动边界的热传导反问题有限点法
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作者 高佳兴 张永富 《内蒙古民族大学学报(自然科学版)》 2026年第1期75-82,共8页
对带有移动边界的非齐次热传导方程反问题进行研究,利用一种基于动态节点布置策略的无网格有限点法求解该问题。当带有噪声数据时,求解源项为不适定问题,结合磨光正则化方法,对方程的源项以及精确解进行同时反演。通过数值算例验证,文... 对带有移动边界的非齐次热传导方程反问题进行研究,利用一种基于动态节点布置策略的无网格有限点法求解该问题。当带有噪声数据时,求解源项为不适定问题,结合磨光正则化方法,对方程的源项以及精确解进行同时反演。通过数值算例验证,文中所用方法对于求解此类带有移动边界的热传导方程反问题是稳定有效的。 展开更多
关键词 热传导反问题 有限点法 移动边界 磨光正则化方法
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Chebyshev谱法求解正则长波方程
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作者 罗妍 宋灵宇 《新疆师范大学学报(自然科学版)》 2026年第1期83-90,共8页
正则长波方程是最重要的非线性偏微分方程之一。文章提出求解正则长波方程的Chebyshev谱法,采用Chebyshev-GaussLobatto配点,利用Chebyshev多项式构造导数矩阵,将一维和二维的正则长波方程近似为常微分方程,证明了正则长波方程的离散Che... 正则长波方程是最重要的非线性偏微分方程之一。文章提出求解正则长波方程的Chebyshev谱法,采用Chebyshev-GaussLobatto配点,利用Chebyshev多项式构造导数矩阵,将一维和二维的正则长波方程近似为常微分方程,证明了正则长波方程的离散Chebyshev谱法的误差估计,采用高阶ODE求解器进行求解。将该方法得到的数值结果与精确解进行比较,验证了方法的有效性,与其他方法相比,本研究的数据结果具有较高的精确度。 展开更多
关键词 正则长波方程 Chebyshev谱法 Chebyshev-Gauss-Lobatto点 CHEBYSHEV多项式
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Robust elastic impedance inversion using L1-norm misfit function and constraint regularization 被引量:1
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作者 潘新朋 张广智 +3 位作者 宋佳杰 张佳佳 王保丽 印兴耀 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期227-235,共9页
The classical elastic impedance (EI) inversion method, however, is based on the L2-norm misfit function and considerably sensitive to outliers, assuming the noise of the seismic data to be the Guassian-distribution.... The classical elastic impedance (EI) inversion method, however, is based on the L2-norm misfit function and considerably sensitive to outliers, assuming the noise of the seismic data to be the Guassian-distribution. So we have developed a more robust elastic impedance inversion based on the Ll-norm misfit function, and the noise is assumed to be non-Gaussian. Meanwhile, some regularization methods including the sparse constraint regularization and elastic impedance point constraint regularization are incorporated to improve the ill-posed characteristics of the seismic inversion problem. Firstly, we create the Ll-norm misfit objective function of pre-stack inversion problem based on the Bayesian scheme within the sparse constraint regularization and elastic impedance point constraint regularization. And then, we obtain more robust elastic impedances of different angles which are less sensitive to outliers in seismic data by using the IRLS strategy. Finally, we extract the P-wave and S-wave velocity and density by using the more stable parameter extraction method. Tests on synthetic data show that the P-wave and S-wave velocity and density parameters are still estimated reasonable with moderate noise. A test on the real data set shows that compared to the results of the classical elastic impedance inversion method, the estimated results using the proposed method can get better lateral continuity and more distinct show of the gas, verifying the feasibility and stability of the method. 展开更多
关键词 elastic impedance (EI) inversion Ll-norm misfit function sparse constraint regularization elastic impedance point constraint regularization IRLS strategy
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A Fixed Point Method for Convex Systems
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作者 Morteza Kimiaei Farzad Rahpeymaii 《Applied Mathematics》 2012年第10期1327-1333,共7页
We present a new fixed point technique to solve a system of convex equations in several variables. Our approach is based on two powerful algorithmic ideas: operator-splitting and steepest descent direction. The quadra... We present a new fixed point technique to solve a system of convex equations in several variables. Our approach is based on two powerful algorithmic ideas: operator-splitting and steepest descent direction. The quadratic convergence of the proposed approach is established under some reasonable conditions. Preliminary numerical results are also reported. 展开更多
关键词 CONVEX EQUATIONS Least SQUARES -regularization Problems Fixed point Quadratically CONVERGENCE
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ON THE EXISTENCE OF COMMON FIXED POINTS FOR A PAIR OF LIPSCHITZIAN MAPPINGS IN BANACH SPACES
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作者 曾六川 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第3期344-354,共11页
The existence of common fixed points for a pair of Lipschitzian mappings in Banach spaces is proved. By using this result, some common fixed point theorems are also established for these mappings in Hilbert spaces, in... The existence of common fixed points for a pair of Lipschitzian mappings in Banach spaces is proved. By using this result, some common fixed point theorems are also established for these mappings in Hilbert spaces, in L p spaces, in Hardy spaces H p, and in Sobolev spaces H r,p , for 1<p<+∞ and r≥0. 展开更多
关键词 asymptotic regularity common fixed point Lipschitzian mapping p- uniformly convex Banach space weak ω-limit set
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Accelerated RHSS Iteration Method for Stabilized Saddle-Point Problems
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作者 Zhenghui Song Pingping Zhang 《Journal of Applied Mathematics and Physics》 2022年第4期1019-1027,共9页
For stabilized saddle-point problems, we apply the two iteration parameters idea for regularized Hermitian and skew-Hermitian splitting (RHSS) method and establish accelerated RHSS (ARHSS) iteration method. Theoretica... For stabilized saddle-point problems, we apply the two iteration parameters idea for regularized Hermitian and skew-Hermitian splitting (RHSS) method and establish accelerated RHSS (ARHSS) iteration method. Theoretical analysis shows that the ARHSS method converges unconditionally to the unique solution of the saddle point problem. Finally, we use a numerical example to confirm the effectiveness of the method. 展开更多
关键词 Stabilized Saddle-point Problems regularized Hermitian and Skew-Hermitian Splitting Iteration Parameters Convergence Property
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Delight and Frustration with Number “Seven” in Plane Geometry and the Regular Heptagon
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作者 A. Wünsche 《Advances in Pure Mathematics》 2021年第1期63-100,共38页
As starting point for patterns with seven-fold symmetry, we investigate the basic possibility to construct the regular heptagon by bicompasses and ruler. To cover the whole plane with elements of sevenfold symmetry is... As starting point for patterns with seven-fold symmetry, we investigate the basic possibility to construct the regular heptagon by bicompasses and ruler. To cover the whole plane with elements of sevenfold symmetry is only possible by overlaps and (or) gaps between the building stones. Resecting small parts of overlaps and filling gaps between the heptagons, one may come to simple parqueting with only a few kinds of basic tiles related to sevenfold symmetry. This is appropriate for parqueting with a center of seven-fold symmetry that is illustrated by figures. Choosing from the basic patterns with sevenfold symmetry small parts as elementary stripes or elementary cells, one may form by their discrete translation in one or two different directions periodic bordures or tessellation of the whole plane but the sevenfold point-group symmetry of the whole plane is then lost and there remains only such symmetry in small neighborhoods around one or more centers. From periodic tiling, we make the transition to aperiodic tiling of the plane. This is analogous to Penrose tiling which is mostly demonstrated with basic elements of fivefold symmetry and we show that this is also possible with elements of sevenfold symmetry. The two possible regular star-heptagons and a semi-regular star-heptagon play here a basic role. 展开更多
关键词 Bicompasses and Ruler Construction regular Heptagon regular and Semi-regular Star-Heptagons point-Group Symmetry C7 and C7v Parqueting Tiling Tessellation Penrose Tiles Symmetry and Antisymmetry Magnetic and Non-Magnetic Classes Time Inversion Color Groups
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Symmetric Reduction of a Regular Controlled Lagrangian System with a Momentum Map
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作者 Hong WANG 《Chinese Annals of Mathematics,Series B》 2026年第1期71-100,共30页
this paper,the author first defines a regular controlled Lagrangian(RCL for short)system on a symplectic fiber bundle,establishing a good expression of the dynamical vector field of an RCL system.This dynamical vector... this paper,the author first defines a regular controlled Lagrangian(RCL for short)system on a symplectic fiber bundle,establishing a good expression of the dynamical vector field of an RCL system.This dynamical vector field synthesizes the Euler-Lagrange vector field and its changes under the actions of the external force and the control.Moreover,the author describes the RCL-equivalence,the RpCL-equivalence,and the RoCL-equivalence,proving regular point and regular orbit reduction theorems for the RCL system and the regular Lagrangian system with symmetry and a momentum map.Finally,as an application the author considers the regular point reducible RCL systems on a generalization of Lie group. 展开更多
关键词 regular controlled Lagrangian system Legendre transformation RCLequivalence Momentum map regular point reduction regular orbit reduction
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由截尾α-稳定过程驱动的种群系统的遍历性
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作者 张振中 顾笑凡 +2 位作者 童俊波 赵馨 李新平 《华东师范大学学报(自然科学版)》 北大核心 2025年第6期1-13,共13页
为了研究生物种群在复杂环境中的动态行为,考虑了一个由截尾α-稳定过程驱动的n维种群模型.首先,建立了一个纯跳情形下的Khasminskii判别定理;其次,讨论了该系统的正则点;最后,给出了此类纯跳系统遍历性的一个判别准则.
关键词 平稳分布 正则点 截尾α-稳定过程
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“平急两用”理念下城市地震应急物资储备点选址研究 被引量:2
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作者 陈瑞琪 刘刚 +2 位作者 张博骞 马东辉 王威 《武汉理工大学学报(信息与管理工程版)》 2025年第2期133-140,共8页
为响应城市建设“存量优先”的政策导向,推动“平急两用”设施建设,提升震后应急物资供给的运行效率,首先,建立应急物资需求点紧迫度评估指标体系,采用熵权-TOPSIS综合评估应急物资需求点的紧迫度并进行分级,为“平急两用”理念下设施... 为响应城市建设“存量优先”的政策导向,推动“平急两用”设施建设,提升震后应急物资供给的运行效率,首先,建立应急物资需求点紧迫度评估指标体系,采用熵权-TOPSIS综合评估应急物资需求点的紧迫度并进行分级,为“平急两用”理念下设施选址提供准确的需求紧迫度评估基础。其次,将“平急两用”理念融入候选点筛选和选址优化模型中,构建“平急两用”理念下的城市地震应急物资储备点多目标优化选址模型,并采用快速非支配排序遗传算法NSGA-Ⅱ求解。最后,以华东某城市地震应急物资储备点的优化选址为例进行分析。结果表明,优化后的应急物资储备点的总成本相较于仅追求覆盖率的情况共优化了582.250~8 540.333万元,同时优化选址方案保障了震后应急物资供给的时效性、公平性和经济性,可为“平急两用”理念下公共基础设施的选址布局提供规划决策支撑。 展开更多
关键词 地震应急物资储备点 “平急两用” 优化选址 应急需求紧迫度 遗传算法
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一种顾及几何约束的机载LiDAR点云建筑物轮廓线提取方法 被引量:1
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作者 石义煌 蔡湛 《测绘科学技术学报》 2025年第1期68-73,共6页
建筑物是城市区域的主要地物之一。建筑物轮廓线的有效提取对于建筑物三维建模十分重要。机载激光雷达技术是近年来较为新颖的直接获取地表信息的手段,用其生成的点云数据可直接提取建筑物轮廓线。针对点云数据提取轮廓线中阈值半径不... 建筑物是城市区域的主要地物之一。建筑物轮廓线的有效提取对于建筑物三维建模十分重要。机载激光雷达技术是近年来较为新颖的直接获取地表信息的手段,用其生成的点云数据可直接提取建筑物轮廓线。针对点云数据提取轮廓线中阈值半径不易控制的问题,提出一种直接从机载激光雷达点云数据提取建筑物轮廓线的方法。首先,进行建筑物轮廓点提取,利用三角函数和斜率来获取初始轮廓点;然后采用多项式和最小二乘原理对轮廓线进行拟合;接着进行轮廓线规则化和轮廓线扩展;最后计算角点。根据实验结果得到的角点中误差可知,该方法能够准确地从点云数据中提取完整的建筑物轮廓线。 展开更多
关键词 机载激光雷达 轮廓点提取 轮廓线拟合 轮廓线规则化 几何约束
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基于数据挖掘探析穴位贴敷治疗化疗相关性恶心呕吐选穴规律
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作者 宋红梅 张金花 《智慧健康》 2025年第24期1-4,共4页
目的探讨穴位贴敷治疗化疗相关性恶心呕吐(CINV)的选穴规律。方法系统检索CNKI、VIP、WanFang和SinoMed数据库,筛选65篇文献建立处方数据库,运用聚类分析和关联规则挖掘技术进行数据挖掘。结果纳入55条有效处方,涉及23个腧穴,总频次184... 目的探讨穴位贴敷治疗化疗相关性恶心呕吐(CINV)的选穴规律。方法系统检索CNKI、VIP、WanFang和SinoMed数据库,筛选65篇文献建立处方数据库,运用聚类分析和关联规则挖掘技术进行数据挖掘。结果纳入55条有效处方,涉及23个腧穴,总频次184次。高频穴位(≥5次)包括足三里、内关、中脘等7穴,76.3%分布于任脉。腧穴归经以任脉(34.8%)、足阳明胃经(21.7%)为主。特定穴中五输穴占比最高(43.5%)。关联规则挖掘显示中脘-神阙为核心配伍组合。结论穴位贴敷治疗CINV以任脉及胃经腧穴为主,通过和胃降逆、补益胃气实现疗效,可为临床选穴提供参考依据。 展开更多
关键词 化疗相关性恶心呕吐 数据挖掘 穴位贴敷 选穴规律
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基于少测点噪声数据重构问题的改进GappyPOD算法
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作者 韩佳洁 苑清扬 +3 位作者 张博 赵鑫 兰天 李郁 《应用科学学报》 北大核心 2025年第5期740-756,共17页
基于数据驱动的GappyPOD(GP)算法是一种解决流动、传热等物理现象中反问题的方法,然而实际数据通常因受到多种噪声污染而影响了GappyPOD算法的精度。伯格斯方程含有流动和传热方程的部分重要形态,以此构建数据库,并对高斯噪声和无规则... 基于数据驱动的GappyPOD(GP)算法是一种解决流动、传热等物理现象中反问题的方法,然而实际数据通常因受到多种噪声污染而影响了GappyPOD算法的精度。伯格斯方程含有流动和传热方程的部分重要形态,以此构建数据库,并对高斯噪声和无规则噪声下,基于普通最小二乘法(ordinary leastsquares,OLS)、加权最小二乘法(weightedleast squares,WLS)、总体最小二乘法(total leastsquares,TLS)及L1正则化的GappyPOD算法的重构精度与稳定性展开研究。研究结果表明,GappyPOD算法可以在仅利用少量残缺数据条件下对一维伯格斯方程实现较高精度的重构;与GP-OLS相比,GP-WLS、GP-TLS和GP-L1的均方根误差显著降低,最大误差明显减小,相关系数更接近于1;在噪声条件下,GP-WLS重构均方根误差比GP-OLS减小到原来的1/27,提高了重构精度;GP-TLS重构均方根误差和最大误差均为最小,分别是0.0141和0.0130,数据矩阵和观测向量均存在噪声时的重构性能最好;GP-L1重构的相关系数接近1,提高了算法趋势预测能力,且从添加噪声前后来看,其重构能力变化程度不大,说明GP-L1算法对于异常值和噪声具有较强的抗干扰能力,提高了模型的鲁棒性能。 展开更多
关键词 GappyPOD算法 最小二乘法 正则化 有限测点 噪声处理
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