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矩阵的奇异值分解在最小二乘法问题上的新应用 被引量:2
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作者 邓亮章 《南昌教育学院学报》 2010年第11期43-43,45,共2页
本文从矩阵的奇异值分解在齐次方程组的最小二乘解法问题上的应用和矩阵的奇异值分解在带约束方程组的最小二乘解法问题上的应用两个方面,探讨了矩阵的奇异值分解在最小二乘法问题上的新应用。
关键词 矩阵 奇异值分解 最小二乘法问题 新应用
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在操作交流中学习在实际情境中解决——人教版二年级上册“用乘法解决问题”教学设计
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作者 林瑜 《福建教育》 2003年第08A期40-41,共2页
关键词 教学情境 人教版 二年级 上册 “用乘法解决问题 教学设计 小学 数学教学 教学目标 学具操作
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让学生体验身边的数学——《用乘法两步计算解决问题》教学片断与评析
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作者 李桂玲 马青山 《湖北教育》 2006年第4期42-43,共2页
让孩子们主动用数学的眼光去观察、审视现实生活中的相关信息.尝试从数学的角度运用所学知识和方法寻找解决实际问题的策略,从而真正成为学习的主体,这已经成为我们的共识。以上教学片断在这方面为我们提供了很好的范例。教师以学生... 让孩子们主动用数学的眼光去观察、审视现实生活中的相关信息.尝试从数学的角度运用所学知识和方法寻找解决实际问题的策略,从而真正成为学习的主体,这已经成为我们的共识。以上教学片断在这方面为我们提供了很好的范例。教师以学生熟悉和喜爱的学校大课间活动为素材,引出数学问题,学生在解决这些问题的过程中, 展开更多
关键词 教学片断 小学 数学教学 课间活动 《用乘法两步计算解决问题 评析
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学会自主“用数学”——《运用乘法知识解决生活中简单的实际问题》教学案例与评析
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作者 肖凤英 《湖北教育》 2004年第13期98-99,共2页
本案例是人教版义务教育课程标准实验教科书《数学》二年级上册第59~60页的教学内容。
关键词 人教版 二年级 上册 《运用乘法知识解决生活中简单的实际问题 教学案例 评析 小学 数学
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将军饮马与最小二乘法——谈数形结合的思想方法
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作者 邢富冲 《中央民族大学学报(自然科学版)》 2007年第4期310-313,共4页
本文介绍体现数形结合思想方法重要性的两个十分精彩的例子.
关键词 数学思想方法 数形结合 将军饮马问题 最小二乘法问题
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一种改进微小卫星伪码测距信噪比的有效方法
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作者 郁发新 金仲和 《传感技术学报》 EI CAS CSCD 北大核心 2006年第3期869-871,877,共4页
微小卫星上的星载测控应答机最基本的功能是接收、解调并转发地面战发来的伪码测距信号,供地面站测距。微小卫星体积小、重量轻、功耗低的特点导致测控应答机工作功率较低和天线增益较小,测距伪码往往淹没在嘈杂的噪声中。严重影响后续... 微小卫星上的星载测控应答机最基本的功能是接收、解调并转发地面战发来的伪码测距信号,供地面站测距。微小卫星体积小、重量轻、功耗低的特点导致测控应答机工作功率较低和天线增益较小,测距伪码往往淹没在嘈杂的噪声中。严重影响后续信号同步信号提取、解调和检测,降低测距精度,甚至导致无法测距。传统基于功率谱带宽的滤波器只能起到一定程度提高信噪比的作用,本文提出基于最小二乘法问题的最小范数准则进行波形拟合的多项式滤波器方法,能够进一步显著提高信噪比,解决强干扰下伪码信号提取的问题。 展开更多
关键词 伪码测距 多项式滤波器 最小二乘法问题
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双对称线性矩阵方程的最佳逼近解(英文) 被引量:1
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作者 林宏程 《数学杂志》 CSCD 北大核心 2011年第2期233-244,共12页
本文讨论了Wang和Chang的双线性矩阵方程(A^T XA,B^T XB)=(C,D)对称解的一致性条件.利用Hilbert空间的投影定理、商奇异值分解及其通解表达式和典型相关分解(CCD)的有效工具,获得了关于这个矩形方阵对的最小二乘问题的明确的解析表达式... 本文讨论了Wang和Chang的双线性矩阵方程(A^T XA,B^T XB)=(C,D)对称解的一致性条件.利用Hilbert空间的投影定理、商奇异值分解及其通解表达式和典型相关分解(CCD)的有效工具,获得了关于这个矩形方阵对的最小二乘问题的明确的解析表达式反对称(或最小Frobenius范数反对称解作为特例)最佳逼近解. 展开更多
关键词 线性矩阵方程 最小二乘法问题 最佳逼近解 典型相关分析分解(CCD) 商奇异值分解(QSVD)
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矩阵代数上的可乘映射 被引量:3
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作者 安桂梅 侯晋川 《山西师范大学学报(自然科学版)》 2002年第1期1-4,共4页
本文得到矩阵代数上可乘映射的一个结构定理 .在此基础上 ,给出矩阵代数上保秩一、保谱半径、保数值半径、保半正定性、保自伴性。
关键词 可乘映射 谱半径 正规矩阵 矩阵代数 乘法保持问题 数值半径
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结构化教学的实践价值与可能 被引量:2
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作者 郑美玲 《福建教育》 2019年第22期40-42,48,共4页
结构化教学是根据知识形成规律和学生的认知发展规律,沟通其元素间的联系,将其转化为学生认知结构的教学方法。列维的'结构主义'、皮亚杰的'认知结构理论'、布鲁纳的'学科基本结构'、奥苏贝尔的'有意义学... 结构化教学是根据知识形成规律和学生的认知发展规律,沟通其元素间的联系,将其转化为学生认知结构的教学方法。列维的'结构主义'、皮亚杰的'认知结构理论'、布鲁纳的'学科基本结构'、奥苏贝尔的'有意义学习理论'都是结构化教学的理论依据。我国最早进行此研究的是北京师范大学冯忠良教授。他于1961年开始'结构化—定向化教学'实验。而影响较大的是华东师范大学叶澜教授的'新基础教育'研究,她总结了'教结构''用结构''长程两段'等策略。 展开更多
关键词 结构化教学 主题图 乘法问题 计量单位 知识抽象化
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应用学本教学理论 创新小学数学课堂 被引量:2
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作者 贾志会 《中国农村教育》 2020年第8期111-111,113,共2页
龚雄飞提出的学本教学理念,符合当代素质教育教学目标的科学教学理念,在小学阶段的数学教学中,基于学本理念对传统数学教学模式进行革新与改良,可以有效的帮助小学学生在数学课堂中,提高数学学习效率,在新课程教学改革的不断推进下,小... 龚雄飞提出的学本教学理念,符合当代素质教育教学目标的科学教学理念,在小学阶段的数学教学中,基于学本理念对传统数学教学模式进行革新与改良,可以有效的帮助小学学生在数学课堂中,提高数学学习效率,在新课程教学改革的不断推进下,小学数学教师应该对传统数学教学模式做好教学反思工作,要有终身学习意识,不断地吸收科学的教学理念,提高自身教育思想觉悟,以此推动小学数学教学模式的创新与发展。 展开更多
关键词 小学数学课堂 数学教学模式 乘法问题 小学数学教师 终身学习意识 教学理念 长方体 小数除法 小数乘法
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分数在教科书中的不同意义(下) 被引量:1
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作者 林碧珍 《小学教学(数学版)》 2019年第5期4-7,共4页
(上接第4期第8页)(三)分数是两数相除的结果(商)。分数是两数相除的结果,如3÷4=3/4,这是分数的第三种意义。至此,3/4有三种解释:(1)根据部分-整体关系,将3/4解读为4等份中的3份,题目情境可以为'1条巧克力有4块,弟弟吃了3块。... (上接第4期第8页)(三)分数是两数相除的结果(商)。分数是两数相除的结果,如3÷4=3/4,这是分数的第三种意义。至此,3/4有三种解释:(1)根据部分-整体关系,将3/4解读为4等份中的3份,题目情境可以为'1条巧克力有4块,弟弟吃了3块。弟弟吃了几条巧克力';(2)根据分数是单位分量的累加,将3/4解读为3个1/4. 展开更多
关键词 乘法问题 小学教材 巧克力 线段图
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Accelerated Matrix Recovery via Random Projection Based on Inexact Augmented Lagrange Multiplier Method 被引量:4
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作者 王萍 张楚涵 +1 位作者 蔡思佳 李林昊 《Transactions of Tianjin University》 EI CAS 2013年第4期293-299,共7页
In this paper, a unified matrix recovery model was proposed for diverse corrupted matrices. Resulting from the separable structure of the proposed model, the convex optimization problem can be solved efficiently by ad... In this paper, a unified matrix recovery model was proposed for diverse corrupted matrices. Resulting from the separable structure of the proposed model, the convex optimization problem can be solved efficiently by adopting an inexact augmented Lagrange multiplier (IALM) method. Additionally, a random projection accelerated technique (IALM+RP) was adopted to improve the success rate. From the preliminary numerical comparisons, it was indicated that for the standard robust principal component analysis (PCA) problem, IALM+RP was at least two to six times faster than IALM with an insignificant reduction in accuracy; and for the outlier pursuit (OP) problem, IALM+RP was at least 6.9 times faster, even up to 8.3 times faster when the size of matrix was 2 000×2 000. 展开更多
关键词 matrix recovery random projection robust principal component analysis matrix completion outlier pursuit inexact augmented Lagrange multiplier method
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Frictional contact algorithm study on the numerical simulation of large deformations in deep soft rock tunnels 被引量:5
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作者 GUO Hongyun CHEN Xin +2 位作者 HE Manchao XI Shouzhong TANG Juzhen 《Mining Science and Technology》 EI CAS 2010年第4期524-529,共6页
There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method... There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method to tackle the nonlinear eontact and large deformation problem in A Software on Large Deformation Analysis for Soft Rock Engineering at Great Depth was presented. In the software, based on Lagrange multiplier method and Coulomb friction law, kinematic constraints on contact boundaries were introduced in functional function, and the finite element equations was established for two incremental large deformation analyses models, polar decomposition model and additive decomposition model. For every incremental loading step, by searching for the contact points in the potential contact interfaces (the excavation boundaries), the Lagrange multipliers, i.e., contact forces are cal- culated iteratively by Gauss-Seidel method, and justified through satisfy the inequalities of static constraint on contact boundaries. With the software, large deformation and frictional contact of a transport roadway were analyzed numerically by the two models. The numerical examples demonstrated the efficiency of the method used in the software. 展开更多
关键词 deep softrock engineering large deformation frictional contact Lagrange multiplier method FEM
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Power Allocation for Energy Harvesting in Wireless Body Area Networks 被引量:1
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作者 Xiaolan Liu Fengye Hu +2 位作者 Meiqi Shao Dan Sui Gengxin He 《China Communications》 SCIE CSCD 2017年第6期22-31,共10页
Wireless Body Area Networks(WBANs) are expected to achieve high reliable communications among a large number of sensors.The outage probability can be used to measure the reliability of the WBAN.In this paper,we optimi... Wireless Body Area Networks(WBANs) are expected to achieve high reliable communications among a large number of sensors.The outage probability can be used to measure the reliability of the WBAN.In this paper,we optimize the outage probability with the harvested energy as constraints.Firstly,the optimal transmit power of the sensor is obtained while considering a single link between an access point(AP) located on the waist and a sensor attached on the wrist over the Rayleigh fading channel.Secondly,an optimization problem is formed to minimize the outage probability.Finally,we convert the non-convex optimization problem into convex solved by the Lagrange multiplier method.Simulations show that the optimization problem is solvable.The outage probability is optimized by performing power allocation at the sensor.And our proposed algorithm achieves minimizing the outage probability when the sensor uses energy harvesting.We also demonstrate that the average outage probability is reduced with the increase of the harvested energy. 展开更多
关键词 wireless body area networks(WBANs) outage probability energy harvesting RELIABILITY
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ON THE MULTIPLICATIVE INVERSE EIGENVALUE PROBLEMS
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作者 张玉海 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2003年第1期31-42,共12页
We present new sufficient conditions on the solvability and numericalmethods for the following multiplicative inverse eigenvalue problem: Given an n × nreal matrix A and n real numbers λ1 , λ2 , . . . ,λn, fin... We present new sufficient conditions on the solvability and numericalmethods for the following multiplicative inverse eigenvalue problem: Given an n × nreal matrix A and n real numbers λ1 , λ2 , . . . ,λn, find n real numbers c1 , c2 , . . . , cn suchthat the matrix diag(c1, c2,..., cn)A has eigenvalues λ1, λ2,..., λn. 展开更多
关键词 线性代数 矩阵 乘法反转特征值问题 数值方法
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Diagrams Produced by Secondary Students in Multiplicative Comparison Word Problems 被引量:1
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《Journal of Mathematics and System Science》 2014年第2期83-92,共10页
We investigated the use of diagrams in multiplicative comparison word problems. The diagrams have been considered as one of the effective heuristic strategies or solving math problems. However, how students use during... We investigated the use of diagrams in multiplicative comparison word problems. The diagrams have been considered as one of the effective heuristic strategies or solving math problems. However, how students use during their school and the degree development that shows in their performance when applied to specific fields of knowledge is a task to be elucidated. We place our study in the school stage in which it makes the transition from arithmetic to algebra and arithmetic problems we focus on in the underlying multiplicative comparison scheme. In this paper, we analyzed the responses of high school students to the translation of multiplicative comparison word problems to representation graphs. We have used the responses of 12 -14 year old students (freshman year of secondary school) to represent multiplicative comparison word problems to identify and categorize the students responses, which allowed us identify categories for each type of representation and hypothesize priority order and subordination between the categories. Results show that students are not familiar with building diagrams that integrate existing relations in word problems. Most of the students do not use all the quantitative information contained in the word problem, therefore draw diagrams referring to the subject or context of the problem without relating to the data in it. We describe in detail the quantitative diagram types produced by these students. We have identified four kinds of quantitative diagrams that the students used to represent the multiplicative comparison problems with inconsistent statements, and these diagrams correspond to the four strategies for tackling the construction of the diagram. 展开更多
关键词 REPRESENTATIONS DIAGRAMS multiplicative comparison word problems.
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A NEW SOLUTION MODEL OF NONLINEAR DYNAMIC LEAST SQUARE ADJUSTMENT
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作者 陶华学 郭金运 《Journal of Coal Science & Engineering(China)》 2000年第2期47-51,共5页
The nonlinear least square adjustment is a head object studied in technology fields. The paper studies on the non derivative solution to the nonlinear dynamic least square adjustment and puts forward a new algorithm m... The nonlinear least square adjustment is a head object studied in technology fields. The paper studies on the non derivative solution to the nonlinear dynamic least square adjustment and puts forward a new algorithm model and its solution model. The method has little calculation load and is simple. This opens up a theoretical method to solve the linear dynamic least square adjustment. 展开更多
关键词 nonlinear least square dynamic adjustment non derivative analytic method
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基于动态规划的迭代算法设计方法 被引量:6
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作者 贺毅朝 张新禄 宋建民 《数学的实践与认识》 北大核心 2016年第6期173-180,共8页
为了基于动态规划法设计求约束最优化问题(COPs)最优解的迭代算法,在避免使用"标记函数"和递归算法的前提下提出了两种求解模式,给出了设计求COPs最优解的迭代算法一般方法,并利用两个典型优化问题-最长公共子序列问题和矩阵... 为了基于动态规划法设计求约束最优化问题(COPs)最优解的迭代算法,在避免使用"标记函数"和递归算法的前提下提出了两种求解模式,给出了设计求COPs最优解的迭代算法一般方法,并利用两个典型优化问题-最长公共子序列问题和矩阵链乘法问题,阐明了如何利用两种求解模式设计求COPs最优解的简捷迭代算法. 展开更多
关键词 动态规划 最优性原理 最长公共子序列问题 矩阵链乘法问题
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再谈《这样列式说得通》
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作者 贺春华 《中小学数学(小学版)》 2004年第1期41-42,共2页
关键词 小学 数学 乘法问题 算式 解法
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Properties and Iterative Methods for the Lasso and Its Variants 被引量:6
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作者 Hong-Kun XU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第3期501-518,共18页
The lasso of Tibshirani (1996) is a least-squares problem regularized by the l1 norm. Due to the sparseness promoting property of the l1 norm, the lasso has been received much attention in recent years. In this pape... The lasso of Tibshirani (1996) is a least-squares problem regularized by the l1 norm. Due to the sparseness promoting property of the l1 norm, the lasso has been received much attention in recent years. In this paper some basic properties of the lasso and two variants of it are exploited. Moreover, the proximal method and its variants such as the relaxed proximal algorithm and a dual method for solving the lasso by iterative algorithms are presented. 展开更多
关键词 Lasso Elastic net Smooth-lasso l1 regulaxization SPARSITY Proximalmethod Dual method Projection THRESHOLDING
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