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Kernel Function-Based Primal-Dual Interior-Point Methods for Symmetric Cones Optimization
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作者 ZHAO Dequan ZHANG Mingwang 《Wuhan University Journal of Natural Sciences》 CAS 2014年第6期461-468,共8页
In this paper, we present a large-update primal-dual interior-point method for symmetric cone optimization(SCO) based on a new kernel function, which determines both search directions and the proximity measure betwe... In this paper, we present a large-update primal-dual interior-point method for symmetric cone optimization(SCO) based on a new kernel function, which determines both search directions and the proximity measure between the iterate and the center path. The kernel function is neither a self-regular function nor the usual logarithmic kernel function. Besides, by using Euclidean Jordan algebraic techniques, we achieve the favorable iteration complexity O( √r(1/2)(log r)^2 log(r/ ε)), which is as good as the convex quadratic semi-definite optimization analogue. 展开更多
关键词 symmetric cones optimization Kernel function Interior-point method polynomial complexity
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Coupling Magneto-Electro-Elastic node-based smoothed radial point interpolation method for free vibration and transient analysis of Functionally Graded Magneto-Electro-Elastic structures 被引量:2
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作者 Liming ZHOU Shuhui REN +2 位作者 Bin NIE Guikai GUO Xiangyang CUI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第1期227-243,共17页
A Coupling Magneto-Electro-Elastic(MEE)Node-based Smoothed Radial Point Interpolation Method(CM-NS-RPIM)was proposed to solve the free vibration and transient responses of Functionally Graded Magneto-Electro-Elastic(F... A Coupling Magneto-Electro-Elastic(MEE)Node-based Smoothed Radial Point Interpolation Method(CM-NS-RPIM)was proposed to solve the free vibration and transient responses of Functionally Graded Magneto-Electro-Elastic(FGMEE)structures.By introducing the modified Newmark method,the displacement,electrical potential and magnetic potential of the structures under transient mechanical loading were obtained.Based on G space theory and the weakened weak(W2)formulation,the equations of the multi-physics coupling problems were derived.Using triangular background elements,the free vibration and transient responses of three numerical examples were studied.Results proved that CM-NS-RPIM performed better than the standard FEM by reducing the overly-stiff of structures.Moreover,CM-NS-RPIM could reduce the number of nodes while guaranteeing the accuracy.Besides,triangular elements could be generated automatically even for complex geometries.Therefore,the effectiveness and validity of CM-NS-RPIM were demonstrated,which were valuable for the design of intelligence devices,such as energy harvesters and sensors. 展开更多
关键词 COUPLING MAGNETO-ELECTRO-ELASTIC node-based smoothed radial point interpolation method functionally Graded MAGNETO-ELECTRO-ELASTIC Gradient smoothing technique Rayleigh damping Transient responses
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IMPROVED HOMOTOPY ITERATION METHOD AND APPLIED TO THE NINE-POINT PATH SYNTHESIS PROBLEM FOR FOUR-BAR LINKAGES 被引量:1
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作者 Zhang Jian Chen Yong (School of Mechanical Engineering, Southwest Jiaotong University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第1期10-16,共7页
A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast a... A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast and efficiently comparing to the original homotopy iteration method. Numerical examples for the ninepoint path synthesis of four-bar linkages show the advantages and efficiency of the improved homotopy iteration method. 展开更多
关键词 Homotopy function Homotopy iteration method Nine-point path synthesis Four-bar linkage
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Polynomial-time interior-point algorithm based on a local self-concordant finite barrier function
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作者 金正静 白延琴 《Journal of Shanghai University(English Edition)》 CAS 2009年第4期333-339,共7页
The choice of self-concordant functions is the key to efficient algorithms for linear and quadratic convex optimizations, which provide a method with polynomial-time iterations to solve linear and quadratic convex opt... The choice of self-concordant functions is the key to efficient algorithms for linear and quadratic convex optimizations, which provide a method with polynomial-time iterations to solve linear and quadratic convex optimization problems. The parameters of a self-concordant barrier function can be used to compute the complexity bound of the proposed algorithm. In this paper, it is proved that the finite barrier function is a local self-concordant barrier function. By deriving the local values of parameters of this barrier function, the desired complexity bound of an interior-point algorithm based on this local self-concordant function for linear optimization problem is obtained. The bound matches the best known bound for small-update methods. 展开更多
关键词 linear optimization self-concordant function finite barrier interior-point methods polynomial-time complexity
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Interior-point algorithm based on general kernel function for monotone linear complementarity problem
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作者 刘勇 白延琴 《Journal of Shanghai University(English Edition)》 CAS 2009年第2期95-101,共7页
A polynomial interior-point algorithm is presented for monotone linear complementarity problem (MLCP) based on a class of kernel functions with the general barrier term, which are called general kernel functions. Un... A polynomial interior-point algorithm is presented for monotone linear complementarity problem (MLCP) based on a class of kernel functions with the general barrier term, which are called general kernel functions. Under the mild conditions for the barrier term, the complexity bound of algorithm in terms of such kernel function and its derivatives is obtained. The approach is actually an extension of the existing work which only used the specific kernel functions for the MLCP. 展开更多
关键词 monotone linear complementarity problem (MLCP) interior-point method kernel function polynomial complexity
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Interior-Point Algorithm for Linear Optimization Based on a New Kernel Function 被引量:2
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作者 CHEN Donghai ZHANG Mingwang LI Weihua 《Wuhan University Journal of Natural Sciences》 CAS 2012年第1期12-18,共7页
In this paper, we design a primal-dual interior-point algorithm for linear optimization. Search directions and proximity function are proposed based on a new kernel function which includes neither growth term nor barr... In this paper, we design a primal-dual interior-point algorithm for linear optimization. Search directions and proximity function are proposed based on a new kernel function which includes neither growth term nor barrier term. Iteration bounds both for large-and small-update methods are derived, namely, O(nlog(n/c)) and O(√nlog(n/ε)). This new kernel function has simple algebraic expression and the proximity function has not been used before. Analogous to the classical logarithmic kernel function, our complexity analysis is easier than the other pri- mal-dual interior-point methods based on logarithmic barrier functions and recent kernel functions. 展开更多
关键词 linear optimization interior-point algorithms pri- mal-dual methods kernel function polynomial complexity
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A New Full-NT-Step Infeasible Interior-Point Algorithm for SDP Based on a Specific Kernel Function
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作者 Samir Bouali Samir Kabbaj 《Applied Mathematics》 2012年第9期1014-1022,共9页
In this paper, we propose a new infeasible interior-point algorithm with full NesterovTodd (NT) steps for semidefinite programming (SDP). The main iteration consists of a feasibility step and several centrality steps.... In this paper, we propose a new infeasible interior-point algorithm with full NesterovTodd (NT) steps for semidefinite programming (SDP). The main iteration consists of a feasibility step and several centrality steps. We used a specific kernel function to induce the feasibility step. The analysis is more simplified. The iteration bound coincides with the currently best known bound for infeasible interior-point methods. 展开更多
关键词 SEMIDEFINITE Programming Full Nesterov-Todd STEPS Infeasible INTERIOR-point methods POLYNOMIAL Complexity KERNEL functions
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A Radial Basis Function Method with Improved Accuracy for Fourth Order Boundary Value Problems
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作者 Scott A. Sarra Derek Musgrave +1 位作者 Marcus Stone Joseph I. Powell 《Journal of Applied Mathematics and Physics》 2024年第7期2559-2573,共15页
Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with... Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with Radial Basis Function methods. The method is used to solve fourth order boundary value problems. The use and location of ghost points are examined in order to enforce the extra boundary conditions that are necessary to make a fourth-order problem well posed. The use of ghost points versus solving an overdetermined linear system via least squares is studied. For a general fourth-order boundary value problem, the recommended approach is to either use one of two novel sets of ghost centers introduced here or else to use a least squares approach. When using either ghost centers or least squares, the random variable shape parameter strategy results in significantly better accuracy than when a constant shape parameter is used. 展开更多
关键词 Numerical Partial Differential Equations Boundary Value Problems Radial Basis function methods Ghost points Variable Shape Parameter Least Squares
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A Modified Full-NT-Step Infeasible Interior-Point Algorithm for SDP Based on a Specific Kernel Function
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作者 Yadan Wang Hongwei Liu Zexian Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第2期41-47,共7页
This paper proposes a new full Nesterov-Todd(NT) step infeasible interior-point algorithm for semidefinite programming. Our algorithm uses a specific kernel function, which is adopted by Liu and Sun, to deduce the fea... This paper proposes a new full Nesterov-Todd(NT) step infeasible interior-point algorithm for semidefinite programming. Our algorithm uses a specific kernel function, which is adopted by Liu and Sun, to deduce the feasibility step. By using the step, it is remarkable that in each iteration of the algorithm it needs only one full-NT step, and can obtain an iterate approximate to the central path. Moreover, it is proved that the iterative bound corresponds with the known optimal one for semidefinite optimization problems. 展开更多
关键词 SEMIDEFINITE programming infeasible INTERIOR-point methods full Nesterov-Todd STEPS KERNEL functions POLYNOMIAL complexity
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振荡乘子算子有界性及其卷积核表示
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作者 蒋博宇 汝少雷 《应用数学》 北大核心 2026年第1期90-97,共8页
本文研究振荡乘子算子在L^(p)空间上的有界性结论,作为波算子的推广得到了一个算子的H^(1)有界性(对于卷积算子H^(1)到L^(1)有界等价于H^(1)上的有界性),然后得到一簇算子及其对应的L^(p)有界性.当振荡指数固定时,我们得到了乘子算子的... 本文研究振荡乘子算子在L^(p)空间上的有界性结论,作为波算子的推广得到了一个算子的H^(1)有界性(对于卷积算子H^(1)到L^(1)有界等价于H^(1)上的有界性),然后得到一簇算子及其对应的L^(p)有界性.当振荡指数固定时,我们得到了乘子算子的卷积核函数,这在推导必要性条件的时候有较重要价值. 展开更多
关键词 振荡乘子算子 BESSEL函数 鞍点近似法
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The Aggregate Homotopy Method for Constrained Sequential Max-min Problems 被引量:1
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作者 于波 刘国新 +1 位作者 冯果忱 李勇 《Northeastern Mathematical Journal》 CSCD 2003年第4期287-290,共4页
关键词 nonsmooth programming aggregate function interior point method homotopy method
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RANDOM APPROXIMATION OF AN ADDITIVE FUNCTIONAL EQUATION OF m-APPOLLONIUS TYPE 被引量:2
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作者 Hassan Azadi Kenary 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1813-1825,共13页
In this paper,using the fixed-point and direct methods,we prove the HyersUlam stability of the following m-Appolonius type functional equation:∑mi=1 f(z-xi)=mf(z-1/m2∑mi=1xi)-1/m∑1≤i〈j≤mf(xi+xj),where m ... In this paper,using the fixed-point and direct methods,we prove the HyersUlam stability of the following m-Appolonius type functional equation:∑mi=1 f(z-xi)=mf(z-1/m2∑mi=1xi)-1/m∑1≤i〈j≤mf(xi+xj),where m is a natural number greater than 1,in random normed spaces. 更多还原 展开更多
关键词 Hyers-Ulam stability additive functional equation random normed space fixed point method
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Penalized interior point approach for constrained nonlinear programming 被引量:1
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作者 陆文婷 姚奕荣 张连生 《Journal of Shanghai University(English Edition)》 CAS 2009年第3期248-254,共7页
A penalized interior point approach for constrained nonlinear programming is examined in this work. To overcome the difficulty of initialization for the interior point method, a problem equivalent to the primal proble... A penalized interior point approach for constrained nonlinear programming is examined in this work. To overcome the difficulty of initialization for the interior point method, a problem equivalent to the primal problem via incorporating an auxiliary variable is constructed. A combined approach of logarithm barrier and quadratic penalty function is proposed to solve the problem. Based on Newton's method, the global convergence of interior point and line search algorithm is proven. Only a finite number of iterations is required to reach an approximate optimal solution. Numerical tests are given to show the effectiveness of the method. 展开更多
关键词 nonlinear programming interior point method barrier penalty function global convergence
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General Solution and Stability of Quattuordecic Functional Equation in Quasi β-Normed Spaces
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作者 K. Ravi J. M. Rassias +1 位作者 S. Pinelas S. Suresh 《Advances in Pure Mathematics》 2016年第12期921-941,共21页
In this paper, we introduce the following quattuordecic functional equation f(x+7y)-14f(x+6y)+91f(x+5y)-364f(x+4y)+1001f(x+3y)-2002f(x+2y)+3003f(x+y)-3432f(x)+3003f(x-y)-2002f(x-2y)+1001f(x-3y)-364f(x-4y)+91f(x-5y)-14... In this paper, we introduce the following quattuordecic functional equation f(x+7y)-14f(x+6y)+91f(x+5y)-364f(x+4y)+1001f(x+3y)-2002f(x+2y)+3003f(x+y)-3432f(x)+3003f(x-y)-2002f(x-2y)+1001f(x-3y)-364f(x-4y)+91f(x-5y)-14f(x-6y)+f(x-7y)=14!f(y), investigate the general solution and prove the stability of this quattuordecic functional equation in quasi &beta;-normed spaces by using the fixed point method. 展开更多
关键词 Quattuordecic functional Equation Fixed point method Hyers-Ulam Rassias Stability Quasi-β-Normed Space
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Orthogonal Stability of Mixed Additive-Quadratic Jensen Type Functional Equation in Multi-Banach Spaces
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作者 Xiuzhong Yang Lidan Chang Guofen Liu 《Advances in Pure Mathematics》 2015年第6期325-332,共8页
In this paper, we prove the Hyers-Ulam stability of the following mixed additive-quadratic Jensen type functional equation:
关键词 Hyers-Ulam STABILITY Additive-Quadratic Jensen TYPE functional Equation Multi-Banach Spaces Fixed point method
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约束优化问题外点罚函数法的几何解释
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作者 雍龙泉 李清华 《高师理科学刊》 2025年第8期66-70,共5页
针对一般约束优化问题,采用外点罚函数法进行求解,通过三个例子展示了外点罚函数法的迭代过程,即从可行域的外部逐渐逼近原问题的最优解。
关键词 约束优化问题 外点罚函数法 迭代过程 几何解释
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铁路软件研发项目费用初步评估模型与指标体系构建研究
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作者 张烁 吕彦昕 +3 位作者 张泽锡 秦秋莉 李杰 刁逢湜 《铁道运输与经济》 北大核心 2025年第9期154-162,共9页
为了提升铁路信息化管理水平,响应全面预算管理和节支降耗的要求,铁路行业领域迫切需要一个更准确、科学、合理的铁路软件研发项目费用初步评估方法。通过挖掘铁路软件的特征,对比分析常用软件研发成本估算方法的优缺点及其在铁路软件... 为了提升铁路信息化管理水平,响应全面预算管理和节支降耗的要求,铁路行业领域迫切需要一个更准确、科学、合理的铁路软件研发项目费用初步评估方法。通过挖掘铁路软件的特征,对比分析常用软件研发成本估算方法的优缺点及其在铁路软件评估方面的适用性,选定以功能点法为基础的国家标准度量规范中的估算流程为核心评估逻辑,研究规模校准、成本估算2部分的关键影响因素,构建规模校准调整因子以及成本估算调整因子指标体系并结合行业基准数据进行指标量化测算,从而得到一个适用于铁路软件研发项目初评的全新评估模型。本研究对于优化铁路信息化立项项目的成本绩效、提高铁路信息化项目经费初步评估的科学性和有效性、确保资金预算与业务发展相匹配具有一定的探索价值和实践意义。 展开更多
关键词 铁路信息化 软件研发费用评估 指标体系 NESMA 软件规模估算 功能点法
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基于改进暗通道先验和ADMM优化的图像盲复原
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作者 赵小强 王涛 宋昭漾 《传感技术学报》 北大核心 2025年第8期1406-1414,共9页
针对运动退化图像中存在较大噪声时,暗通道先验无法准确估计点扩散函数和在最大后验框架下采用梯度先验约束难以求得最优解的问题,提出一种基于改进暗通道先验和ADMM优化的运动退化图像盲复原算法。首先,根据分数阶具备非线性保留低频... 针对运动退化图像中存在较大噪声时,暗通道先验无法准确估计点扩散函数和在最大后验框架下采用梯度先验约束难以求得最优解的问题,提出一种基于改进暗通道先验和ADMM优化的运动退化图像盲复原算法。首先,根据分数阶具备非线性保留低频成分和抑制噪声的特点,使其对暗通道先验进行改进;然后通过改进的暗通道先验构造出点扩散函数估算模型并采用半二次方分裂方法解决其非凸问题;在对点扩散函数进行复原时,采用由粗到细的多尺度交替迭代优化框架,使得迭代出的最大尺度点扩散函数更加精确;最后建立导数空间总变分模型,利用交替方向乘子法(ADMM)对其进行优化,从而达到在导数空间总变分模型之下可以收敛到最优解、复原出更多图像细节的目的。实验结果表明:所提算法可以有效降低图像中的噪声、伪影和振铃现象,使得复原出的图像更加清晰、具有更多的图像细节。 展开更多
关键词 图像处理 运动退化图像盲复原 暗通道先验 点扩散函数 多尺度 交替方向乘子法
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基于罚函数-高斯牛顿法的冗余采摘机器人逆解方法
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作者 林桂潮 曾文勇 +3 位作者 徐垚 傅文平 黄旭熙 朱立学 《农业机械学报》 北大核心 2025年第9期355-362,共8页
7自由度冗余采摘机器人灵巧度高,可在非结构化果园进行避障作业,而传统逆运动学数值解法未约束关节运动范围,常导致逆解失效。本文提出一种基于高斯牛顿法和外点罚函数法的冗余采摘机器人逆运动学解法。设计一种由1自由度平移导轨和6自... 7自由度冗余采摘机器人灵巧度高,可在非结构化果园进行避障作业,而传统逆运动学数值解法未约束关节运动范围,常导致逆解失效。本文提出一种基于高斯牛顿法和外点罚函数法的冗余采摘机器人逆运动学解法。设计一种由1自由度平移导轨和6自由度串联机械臂组成的采摘机器人;采用改进的DH参数法描述机器人各连杆几何参数和位置关系,建立机器人正运动学模型,确立其工作空间;以机器人末端位姿与目标位姿之间的欧氏距离作为目标函数,使用外点罚函数法构造关节约束项以避免机器人在运动中超程,应用机器人雅可比矩阵和高斯牛顿法优化目标函数,建立机器人关节角度与目标位姿之间的非线性映射关系。仿真试验结果表明,当位置误差小于10^(-7)mm和姿态误差小于10^(-7)rad时,本文方法逆解成功率为99.8%,比高斯牛顿法高29.8个百分点;平均运算时间为37.1 ms,比高斯牛顿法减少40%。田间试验结果表明,本文逆解方法在末端执行器宽度、前后、高度方向上定位误差(平均值±标准差)分别为(2.6±1.4)mm、(-5.7±6.9)mm、(2.4±2.8)mm,果梗夹持成功率为77.0%。本文方法逆解成功率和实时性高,误差较小,可为7自由度冗余采摘机器人应用提供技术参考。 展开更多
关键词 七自由度采摘机器人 逆运动学 高斯牛顿法 外点罚函数法
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三维人体特征点自动提取的研究与应用 被引量:1
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作者 姚怡 毛玥 +1 位作者 蒙冉菊 金子敏 《丝绸》 北大核心 2025年第2期75-81,共7页
人体特征点准确快速地提取是三维人体尺寸测量、三维人体建模、体型分类等的基础,文章综述了三维人体特征点提取的重要性与困难,以及几何形状分析法、函数法、模板法这三种主要提取方法的原理、特点和应用现状。几何形状分析法计算较为... 人体特征点准确快速地提取是三维人体尺寸测量、三维人体建模、体型分类等的基础,文章综述了三维人体特征点提取的重要性与困难,以及几何形状分析法、函数法、模板法这三种主要提取方法的原理、特点和应用现状。几何形状分析法计算较为简单,但受体型差异影响较大;函数法方法简单,但拟合精度较低;模板法精度较高但计算量大,且模型库构建成本高。最后,指出了三维人体特征点自动提取的研究应重点突破特征点提取过程中由体型差异、姿态变化等因素带来的难点,开发具备更高鲁棒性、适用性强的自动化算法,以实现更精确、快速的三维人体特征点自动提取。 展开更多
关键词 三维人体 特征点自动提取 几何形状分析法 函数法 模板法
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