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USING FREDHOLM INTEGRAL EQUATION OF THE SECOND KINDTO SOLVE THE VERTICAL VIBRATION OF ELASTICPLATE ON AN ELASTIC HALF SPACE
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作者 金波 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第2期157-162,共6页
The dual integral equations of vertical forced vibration of elastic plate on an elastic half space subject to harmonic uniform distribution loading are established according to the mixed boundary-value condition. By a... The dual integral equations of vertical forced vibration of elastic plate on an elastic half space subject to harmonic uniform distribution loading are established according to the mixed boundary-value condition. By applying Abel transformation the dual integral equations are reduced to Fredholm integral equation of the second kind which is solved numerically. 展开更多
关键词 elastic half space elastic plate dynamic response Fredholm integral equation of the second kind
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The Successive Approximation Method for Solving Nonlinear Fredholm Integral Equation of the Second Kind Using Maple
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作者 Dalal Adnan Maturi 《Advances in Pure Mathematics》 2019年第10期832-843,共12页
In this paper, we will use the successive approximation method for solving Fredholm integral equation of the second kind using Maple18. By means of this method, an algorithm is successfully established for solving the... In this paper, we will use the successive approximation method for solving Fredholm integral equation of the second kind using Maple18. By means of this method, an algorithm is successfully established for solving the non-linear Fredholm integral equation of the second kind. Finally, several examples are presented to illustrate the application of the algorithm and results appear that this method is very effective and convenient to solve these equations. 展开更多
关键词 NONLINEAR FREDHOLM INTEGRAL Equation of the second kind Successive Approximation Method Maple18
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CRITICAL DAMPING OF THE SECOND-ORDERPENDULUM-LIKE SYSTEMS
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作者 李鑫滨 黄永念 +1 位作者 杨莹 黄琳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第1期7-16,共10页
First,the properties of solutions of a typical second-order pendulum-like system with a specified nonlinear function were discussed.Then the case with a general form of nonlinearity is considered and its global proper... First,the properties of solutions of a typical second-order pendulum-like system with a specified nonlinear function were discussed.Then the case with a general form of nonlinearity is considered and its global properties were studied by using the qualitative theory of differential equations.As a result,sufficient conditions for estimating the critical damp are established,which improves the work by Leonov et al. 展开更多
关键词 pendulum-like system lagrange stability gradient-like behavior limit cycles of the second kind
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Theoretical and Experimental Studies of the Effect of Inclined Scraper on Removal of Raw Cotton from Mesh Surface 被引量:3
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作者 Muradov Rustam Muradovich Karimov Abdusamat Ismonovich Mardanov Botir Mardanovich 《World Journal of Mechanics》 2014年第12期371-377,共7页
The present manuscript deals with theoretical and experimental studies of the effect of inclined scraper on removal raw cotton from mesh surface. The mathematical model of the problem and theoretical studies of the mo... The present manuscript deals with theoretical and experimental studies of the effect of inclined scraper on removal raw cotton from mesh surface. The mathematical model of the problem and theoretical studies of the motion of cotton mass on plane of scraper is derived taking into account material point by accomplishing plane motion in the mesh surface. Graphs of the experiment shows that performance of scraper inclined to the radius of the disk by the value α=30° to the surface mesh β=110°, optimally allows to reduce the formation of technological defects of raw cotton. The presence of zero-pressure portion on the mesh surface of separator may provide complete removal of cotton from its surface and to eliminate grid clogging. 展开更多
关键词 Cotton AIR SCRAPER SHAFT SEPARATOR Radial and ANGULAR AIR Speed lagrange equations of the second kind Trajectory
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Numerical Algorithms for Solving One Type of Singular Integro-Differential Equation Containing Derivatives of the Time Delay States 被引量:1
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作者 Shihchung Chiang Terry L. Herdman 《Applied Mathematics》 2015年第8期1294-1301,共8页
This study presents numerical algorithms for solving a class of equations that partly consists of derivatives of the unknown state at previous certain times, as well as an integro-differential term containing a weakly... This study presents numerical algorithms for solving a class of equations that partly consists of derivatives of the unknown state at previous certain times, as well as an integro-differential term containing a weakly singular kernel. These equations are types of integro-differential equation of the second kind and were originally obtained from an aeroelasticity problem. One of the main contributions of this study is to propose numerical algorithms that do not involve transforming the original equation into the corresponding Volterra equation, but still enable the numerical solution of the original equation to be determined. The feasibility of the proposed numerical algorithm is demonstrated by applying examples in measuring the maximum errors with exact solutions at every computed nodes and calculating the corresponding numerical rates of convergence thereafter. 展开更多
关键词 Integro-Differential Equation of the second kind WEAKLY SINGULAR KERNEL Numerical Algorithms Rates of Convergence
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The Second-Order Differential Equation System with the Feedback Controls for Solving Convex Programming
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作者 Xingxu Chen Li Wang +1 位作者 Juhe Sun Yanhong Yuan 《Open Journal of Applied Sciences》 2022年第6期977-989,共13页
In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent opera... In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent operator equations for the convex programming problems under the certain conditions are obtained. Then a second-order differential equation system with the feedback controls is constructed on the basis of operator equation. We prove that any accumulation point of the trajectory of the second-order differential equation system with the feedback controls is a solution to the convex programming problem. In the end, two examples using this differential equation system are solved. The numerical results are reported to verify the effectiveness of the second-order differential equation system with the feedback controls for solving the convex programming problem. 展开更多
关键词 Convex Programming lagrange Function Projection Operator second-Order Differential Equation
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PRECONDITIONED CONJUGATE GRADIENT METHODS FOR INTEGRAL EQUATIONS OF THE SECOND KIND DEFINED ON THE HALF-LINE
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作者 Chan, RH Lin, FR 《Journal of Computational Mathematics》 SCIE CSCD 1996年第3期223-236,共14页
We consider solving integral equations of the second kind defined on the half-line [0, infinity) by the preconditioned conjugate gradient method. Convergence is known to be slow due to the non-compactness of the assoc... We consider solving integral equations of the second kind defined on the half-line [0, infinity) by the preconditioned conjugate gradient method. Convergence is known to be slow due to the non-compactness of the associated integral operator. In this paper, we construct two different circulant integral operators to be used as preconditioners for the method to speed up its convergence rate. We prove that if the given integral operator is close to a convolution-type integral operator, then the preconditioned systems will have spectrum clustered around 1 and hence the preconditioned conjugate gradient method will converge superlinearly. Numerical examples are given to illustrate the fast convergence. 展开更多
关键词 MATH Cr PRECONDITIONED CONJUGATE GRADIENT METHODS FOR INTEGRAL equations of the second kind DEFINED ON the HALF-LINE PRO III
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基于Hamilton体系的Lagrange方程盒式倾转旋翼无人机建模 被引量:1
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作者 吴翰 王正平 +1 位作者 周洲 王睿 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2020年第12期2320-2328,共9页
针对倾转旋翼飞行器动态倾转过程中动力学建模问题进行了研究。首先,从多体动力学出发,以某盒式倾转旋翼无人机为算例,将该无人机假设成由机翼、机体、涵道风扇、倾转旋翼等组成的多刚体系统。其次,通过不同刚体质心间的位移约束,建立... 针对倾转旋翼飞行器动态倾转过程中动力学建模问题进行了研究。首先,从多体动力学出发,以某盒式倾转旋翼无人机为算例,将该无人机假设成由机翼、机体、涵道风扇、倾转旋翼等组成的多刚体系统。其次,通过不同刚体质心间的位移约束,建立该无人机系统的非保守力和力矩矩阵,以及动能、势能、余虚功和逆势能模型。最后,分别基于Hamilton体系下的Lagrange方程和第二类Lagrange方程推导并建立了该盒式倾转旋翼无人机的动力学模型。仿真结果表明:两类Lagrange方程所建动力学模型的仿真结果与实验数据一致,验证了所提建模方法的合理性;在倾转旋翼转速不变的情况下,倾转过程所用时间越长,无人机掉高越少,轨迹越光滑,但输入能量越多,具体倾转过程的设计要根据实际输入能量、倾转时间等需求进行确定。 展开更多
关键词 倾转旋翼飞行器 盒式翼布局 Hamilton体系下lagrange方程 第二类lagrange方程 多体动力学
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第二类勒让德函数的重规格化及其优化
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作者 张捍卫 杨永勤 +1 位作者 李晓玲 张华 《测绘学报》 EI CSCD 北大核心 2024年第7期1298-1307,共10页
椭球谐函数级数展开是地球重力场椭球谐建模的基础。然而,处理椭球谐函数级数的主要困难在于计算第二类勒让德函数。而Jekeli的重规格化方法简化了这一计算过程。本文在Jekeli重规格化的基础上,详细推导了两种基于高斯超几何函数变换的... 椭球谐函数级数展开是地球重力场椭球谐建模的基础。然而,处理椭球谐函数级数的主要困难在于计算第二类勒让德函数。而Jekeli的重规格化方法简化了这一计算过程。本文在Jekeli重规格化的基础上,详细推导了两种基于高斯超几何函数变换的优化递归方法,同时利用这两种优化递归的方法计算了第二类勒让德函数,并将其展开到二阶导数。通过数值计算,证明了优化递归方法可以有效加快收敛,缩短计算时间,并且适用阶数更高,这使得椭球谐函数级数在实际应用中更加方便、可行。 展开更多
关键词 第二类勒让德函数 缔合勒让德微分方程 重规格化 高斯超几何函数
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非线性非自治非保守阻尼系统的第二类Lagrange方程 被引量:1
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作者 田红亮 朱大林 《三峡大学学报(自然科学版)》 CAS 2006年第5期435-439,共5页
基于非自治有阻尼系统推导了第二类Lagrange方程,使用虚功原理,给出了广义力的求解方法,广义力由广义保守力、广义耗散力、除广义保守力和广义耗散力以外的对应于广义坐标的广义力这3部分组成.利用第二类Lagrange方程推导了一级倒立摆... 基于非自治有阻尼系统推导了第二类Lagrange方程,使用虚功原理,给出了广义力的求解方法,广义力由广义保守力、广义耗散力、除广义保守力和广义耗散力以外的对应于广义坐标的广义力这3部分组成.利用第二类Lagrange方程推导了一级倒立摆非保守有阻尼系统的运动微分方程和状态空间模型.用数值分析软件Matlab 6.5对状态空间模型进行了线性二次调节器最优控制. 展开更多
关键词 第二类lagrange方程 广义独立坐标 虚功 线性二次调节器
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Karhunen-Loeve展开在Abaqus中的实现
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作者 胡烨之 张雅琪 《计算机辅助工程》 2024年第2期44-49,60,共7页
基于数值分析理论,提出一种Karhunen-Loeve展开的数值算法,采用Python和Fortran混合编码的方式将其内嵌至Abaqus的计算内核中,分析程序编制的关键要素并开展误差分析。结果表明:编制的程序可行,随机场展开合理,数值算法精度较高,特征值... 基于数值分析理论,提出一种Karhunen-Loeve展开的数值算法,采用Python和Fortran混合编码的方式将其内嵌至Abaqus的计算内核中,分析程序编制的关键要素并开展误差分析。结果表明:编制的程序可行,随机场展开合理,数值算法精度较高,特征值、特征函数以及协方差函数的计算结果与理论解一致。 展开更多
关键词 随机场 ABAQUS Karhunen-Loeve展开 协方差函数 第二类Fredholm积分
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第二类Fredholm模糊积分方程的模糊数值解
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作者 刘雪铃 黄静 +1 位作者 冯依虎 崔钰晗 《滨州学院学报》 2024年第2期46-51,共6页
研究了一类模糊集意义下的第二类Fredholm模糊积分方程的数值解。采用残余幂级数法得到第二类Fredholm模糊积分方程的k级截断级数解,将第二类Fredholm模糊积分方程的数值解用泰勒光滑公式展开,并通过代数方程组求解出相关系数。最后,结... 研究了一类模糊集意义下的第二类Fredholm模糊积分方程的数值解。采用残余幂级数法得到第二类Fredholm模糊积分方程的k级截断级数解,将第二类Fredholm模糊积分方程的数值解用泰勒光滑公式展开,并通过代数方程组求解出相关系数。最后,结合数值算例证明了残余幂级数方法的稳定性和收敛性。 展开更多
关键词 第二类Fredholm模糊积分方程 残余幂级数法 模糊微分方程 数值解 模糊函数
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Lagrange插值多项式平均算子的逼近
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作者 姜功建 《河北机电学院学报》 1991年第4期57-62,共6页
本文引入以第二类 Chebyshev 多项式 U_n(x)的零点为基点的 Lagrange 插值多项式平均算子 F_n(f,x),研究用 F_n(f,x)逼近连续函数 f(x)的阶。
关键词 多项式 朗曼插值 平均算子 逼近
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Infinite Sequence Soliton-Like Exact Solutions of (2 + 1)-Dimensional Breaking Soliton Equation 被引量:17
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作者 Taogetusang Sirendaoerji 李姝敏 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第6期949-954,共6页
寻求新无限的顺序象 soliton 一样非线性的进化方程的准确答案(旧姓) 由在辅助方程方法上开发建设和机械化的二个特征,秒种椭圆形的方程高度被学习并且新类型答案和 B ? cklund 转变被获得。( 2+1 )然后,维的碎 soliton 方程作为一个... 寻求新无限的顺序象 soliton 一样非线性的进化方程的准确答案(旧姓) 由在辅助方程方法上开发建设和机械化的二个特征,秒种椭圆形的方程高度被学习并且新类型答案和 B ? cklund 转变被获得。( 2+1 )然后,维的碎 soliton 方程作为一个例子和它的无限的顺序被选象soliton一样准确解决方案在符号的计算系统 Mathematica 的帮助下被构造,它包括无限的顺序 Jacobi 椭圆形的类型的光滑的象soliton一样解决方案, Jacobi 椭圆形的类型的无限的顺序协议 soliton 解决方案和指数的函数类型和三角形的功能的无限的顺序山峰 soliton 解决方案打字。 展开更多
关键词 破裂孤子方程 无限序列 精确解 Mathematica BACKLUND变换 Jacobi 非线性演化方程 符号计算系统
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MULTILEVEL AUGMENTATION METHODS FOR SOLVING OPERATOR EQUATIONS 被引量:4
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作者 陈仲英 巫斌 许跃生 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第1期31-55,共25页
We introduce multilevel augmentation methods for solving operator equations based on direct sum decompositions of the range space of the operator and the solution space of the operator equation and a matrix splitting ... We introduce multilevel augmentation methods for solving operator equations based on direct sum decompositions of the range space of the operator and the solution space of the operator equation and a matrix splitting scheme. We establish a general setting for the analysis of these methods, showing that the methods yield approximate solutions of the same convergence order as the best approximation from the subspace. These augmentation methods allow us to develop fast, accurate and stable nonconventional numerical algorithms for solving operator equations. In particular, for second kind equations, special splitting techniques are proposed to develop such algorithms. These algorithms are then applied to solve the linear systems resulting from matrix compression schemes using wavelet-like functions for solving Fredholm integral equations of the second kind. For this special case, a complete analysis for computational complexity and convergence order is presented. Numerical examples are included to demonstrate the efficiency and accuracy of the methods. In these examples we use the proposed augmentation method to solve large scale linear systems resulting from the recently developed wavelet Galerkin methods and fast collocation methods applied to integral equations of the secondkind. Our numerical results confirm that this augmentation method is particularly efficient for solving large scale linear systems induced from wavelet compression schemes. 展开更多
关键词 多级增加法 算符方程 计算方法 线性系统 积分方程
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Fast Solvers of Fredholm Optimal Control Problems
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作者 Mario Annunziato Alfio Borzi 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2010年第4期431-448,共18页
The formulation of optimal control problems governed by Fredholm integral equations of second kind and an efficient computational framework for solving these control problems is presented. Existence and uniqueness of ... The formulation of optimal control problems governed by Fredholm integral equations of second kind and an efficient computational framework for solving these control problems is presented. Existence and uniqueness of optimal solutions is proved.A collective Gauss-Seidel scheme and a multigrid scheme are discussed. Optimal computational performance of these iterative schemes is proved by local Fourier analysis and demonstrated by results of numerical experiments. 展开更多
关键词 CONTROL PROBLEMS CONTROL PROBLEMS FREDHOLM integral equations EXISTENCE and UNIQUENESS optimal solutions FOURIER analysis performance framework results kind
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ASYMPTOTIC ERROR EXPANSION FOR THE NYSTROM METHOD OF NONLINEAR VOLTERRA INTEGRAL EQUATION OF THE SECOND KIND
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作者 Han Guo-qiang (Dept. Of Comp, Science, South China University of Science and Technology, Guangzhou, China) 《Journal of Computational Mathematics》 SCIE CSCD 1994年第1期31-35,共5页
While the numerical solution of one-dimensional Volterra integral equations of the second kind with regular kernels is well understood, there exist no systematic studies of asymptotic error expansion for the approxima... While the numerical solution of one-dimensional Volterra integral equations of the second kind with regular kernels is well understood, there exist no systematic studies of asymptotic error expansion for the approximate solution. In this paper,we analyse the Nystrom solution of one-dimensional nonlinear Volterra integral equation of the second kind and show that approkimate solution admits an asymptotic error expansion in even powers of the step-size h, beginning with a term in h2. So that the Richardson's extrapolation can be done. This will increase the accuracy of numerical solution greatly. 展开更多
关键词 ASYMPTOTIC ERROR EXPANSION FOR the NYSTROM METHOD of NONLINEAR VOLTERRA INTEGRAL EQUATION of the second kind
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用无穷矩阵方程求解第二类Stirling数表示的自然数幂和 被引量:1
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作者 唐军强 艾英 《高师理科学刊》 2023年第1期20-23,共4页
讨论了4个用第二类Stirling数表示的自然数的幂和公式.利用升阶乘和降阶乘的定义式,得到关于各阶幂和的递推关系,用求解无穷矩阵方程的方法给出用第二类Stirling数表示的幂和公式,并证明了它们之间的等价性.
关键词 无穷矩阵方程 自然数 幂和 第一类STIRLING数 第二类STIRLING数
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Volterra型积分微分方程Chebyshev谱配置法求解
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作者 方春华 黄超兰 王建雨 《大连理工大学学报》 CAS CSCD 北大核心 2023年第2期215-220,共6页
采用Chebyshev谱配置法求解Volterra型积分微分方程.首先将积分微分方程改写成等价的第二类Volterra积分方程组,再取Clenshaw-Curtis点为配置点,然后利用Clenshaw-Curtis求积法则离散方程中积分项得到配置方程组,最后给出在L∞范数空间... 采用Chebyshev谱配置法求解Volterra型积分微分方程.首先将积分微分方程改写成等价的第二类Volterra积分方程组,再取Clenshaw-Curtis点为配置点,然后利用Clenshaw-Curtis求积法则离散方程中积分项得到配置方程组,最后给出在L∞范数空间下的误差分析,并用数值实例验证理论分析的结果.该方法既有谱精度,程序又易实现. 展开更多
关键词 VOLTERRA型积分微分方程 第二类Volterra积分方程组 Chebyshev谱配置法 Clenshaw-Curtis求积 谱精度
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基于CFD/CSD弱耦合方法的后掠尖旋翼气弹响应分析
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作者 韩伟 肖中云 +1 位作者 郭永恒 雷永强 《机械设计与制造》 北大核心 2023年第4期114-117,共4页
准确计算旋翼的气弹响应,对于旋翼的设计与振动控制具有重要的意义。传统的旋翼气动模型通常采用简单的叶素理论、自由尾迹方法,导致气动力计算精度较差。这里的CFD计算采用非定常重叠动网格计算方法,通过直接求解Navier-Stokes方程的... 准确计算旋翼的气弹响应,对于旋翼的设计与振动控制具有重要的意义。传统的旋翼气动模型通常采用简单的叶素理论、自由尾迹方法,导致气动力计算精度较差。这里的CFD计算采用非定常重叠动网格计算方法,通过直接求解Navier-Stokes方程的方法获得尾迹,旋翼的流场网格采用多重动网格方法生成。CSD计算采用有限体积梁单元建立桨叶的有限体积梁模型,边界条件采用第一类拉格朗日乘子法进行考虑。流固耦合交界面的气动力计算结果通过插值和积分映射到CSD模型上,在此基础上进行旋翼的气弹响应分析。 展开更多
关键词 CFD/CSD NAVIER-STOKES方程 有限体积梁单元 第一类拉格朗日乘子法
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