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Multiquadric方法在中尺度气象资料客观分析中的应用 被引量:8
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作者 何斌 黄渊 陈亮 《高原气象》 CSCD 北大核心 2014年第1期171-178,共8页
利用浙江省中尺度自动站的温度资料,引入已广泛应用于测绘、地球物理、地图绘制等领域的Multiquadric插值法,并与目前气象领域内采用较多的Cressman方法进行比较,分析两者在不同站点分布和数量下对实况场的逼近程度,并对Multiquadric中... 利用浙江省中尺度自动站的温度资料,引入已广泛应用于测绘、地球物理、地图绘制等领域的Multiquadric插值法,并与目前气象领域内采用较多的Cressman方法进行比较,分析两者在不同站点分布和数量下对实况场的逼近程度,并对Multiquadric中的自由设定参数进行讨论。结果表明,总体而言,Multiquadric方法的均方根误差小于Cressman方法。当站点数为100时,两者差异达0.3℃;当站点数>1000时,Multiquadric方法相对Cressman的改进已经<1%,两者差异非常小。在站点数较少或是站点间隔较大的情况下,Cressman方法较易产生虚假中心,而Multiquadric方法则更加接近实况。Multiquadric平滑参数λ可以被认为是一种低通滤波器,它将高频波滤去,留下较大尺度的系统,同时冷暖空气温度中心的强度随着平滑强度的增加也逐渐减弱。Multiquadric参数c存在一个上限值,当c大于或小于该值时,客观分析结果表现出不同的敏感度。 展开更多
关键词 multiquadric方法 客观分析 中尺度自动站 Cressman方法
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用Multiquadric方法实现医学图像的弹性配准 被引量:4
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作者 张煜 江贵平 +3 位作者 李树祥 刘哲星 谢小棉 陈武凡 《第一军医大学学报》 CSCD 北大核心 2002年第7期584-587,共4页
目的 改进医学图像弹性配准的精确度和配准方法的稳定性,并简化配准操作。方法 利用Multiquadric插值方法的可平滑性质,将其与一种半自动标记点选择方法结合,建立一种新配准方法。结果 运用此方法进行医学图像的弹性配准,实现了标准... 目的 改进医学图像弹性配准的精确度和配准方法的稳定性,并简化配准操作。方法 利用Multiquadric插值方法的可平滑性质,将其与一种半自动标记点选择方法结合,建立一种新配准方法。结果 运用此方法进行医学图像的弹性配准,实现了标准图像与变形图像的快速、准确配准。结论 我们建立的配准方法是一种准确、简便和稳定的方法。 展开更多
关键词 影像处理 弹性配准 multiquadric方法 医学图像
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一种新的Multiquadric拟插值 被引量:4
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作者 陈荣华 韩旭里 吴宗敏 《工程图学学报》 CSCD 北大核心 2010年第3期117-121,共5页
Multiquadric(MQ)是由Hardy提出来的一种径向基函数,至今它已在大地测量学、微分方程数值解等许多方面得到了应用。目前已知的multiquadric拟插值有4种,即,Beatson和Powell的LA、LB和LC以及Wu和Schaback的LD,其中,LB是常数再生的,LC和L... Multiquadric(MQ)是由Hardy提出来的一种径向基函数,至今它已在大地测量学、微分方程数值解等许多方面得到了应用。目前已知的multiquadric拟插值有4种,即,Beatson和Powell的LA、LB和LC以及Wu和Schaback的LD,其中,LB是常数再生的,LC和LD是线性再生的。该文首先给出形如LD的拟插值线性再生时其基函数应具有的性质,然后构造了一种具有线性再生性和保单调性的multiquadric拟插值,并对其逼近误差进行了理论分析。最后,通过两个实例进行数值实验,从算例的结果来看,该拟插值具有良好的逼近精度。 展开更多
关键词 计算数学 数值逼近 数值分析 multiquadric(MQ)拟插值 线性再生 保单调
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空间分数阶扩散方程的Multiquadric拟插值解法 被引量:4
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作者 王自强 曹俊英 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2015年第3期358-363,共6页
基于拟插值算子对空间分数阶扩散方程构造了一个新的数值格式.首先在散落点上用三次Multiquadric(MQ)函数的平移构造了一个拟插值算子,分析了此拟插值算子的再生性、保形性和对分数阶导数的收敛性,最后利用上述拟插值算子并结合时间差... 基于拟插值算子对空间分数阶扩散方程构造了一个新的数值格式.首先在散落点上用三次Multiquadric(MQ)函数的平移构造了一个拟插值算子,分析了此拟插值算子的再生性、保形性和对分数阶导数的收敛性,最后利用上述拟插值算子并结合时间差分格式构造了空间分数阶扩散方程的计算格式.收敛性分析显示:当时间方向用Crank-Nicolson格式时,精度为O(Δt2+h4-α),当时间方向用向后Euler格式时,精度为O(Δt+h4-α),其中Δt为时间步长,h为空间步长.数值结果表明MQ拟插值方法是构造数值格式的一个有效工具. 展开更多
关键词 multiquadric拟插值 分数阶扩散方程 保形性 逼近性分析
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非矩形定义域上的散乱数据曲面重建的Multiquadric基函数拟合法 被引量:2
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作者 李卫国 陈文亮 蔡喁 《计算机工程与应用》 CSCD 北大核心 2001年第23期78-80,共3页
传统的Multiquadric基函数拟合散乱数据方法,只能用于定义域呈矩形拓扑的散乱数据集上,而逆向工程中通常遇到的是非矩形定义域上的散乱数据集,因此不能用传统方法。文章提出一种新的Multiquadric基函数拟合非矩形定义域上的散乱数据集... 传统的Multiquadric基函数拟合散乱数据方法,只能用于定义域呈矩形拓扑的散乱数据集上,而逆向工程中通常遇到的是非矩形定义域上的散乱数据集,因此不能用传统方法。文章提出一种新的Multiquadric基函数拟合非矩形定义域上的散乱数据集。该方法首先找到一个与该散乱数据集所在曲面拓扑等价的参数曲面,通过将散乱数据点(xi,yi,zi)一一映射到此参数曲面,反求出其对应参数(ui,vi),由于(ui,vi)∈犤0,1犦×犤0,1犦,从而将非矩形定义域上的Multiquadric基函数拟合方法转化为传统的方法。将Multiquadric曲面与B-样条曲面进行了比较,指出了Multiquadric曲面优于B-样条曲面之处。 展开更多
关键词 multiquadric基函数 散乱数据 曲面重建 逆向工程 非矩形定义域 计算机辅助设计
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A numerical method for one-dimensional nonlinear sine-Gordon equation using multiquadric quasi-interpolation 被引量:5
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作者 马利敏 吴宗敏 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3099-3103,共5页
In this paper, we use a univariate multiquadric quasi-interpolation scheme to solve the one-dimensional nonlinear sine-Gordon equation that is related to many physical phenomena. We obtain a numerical scheme by using ... In this paper, we use a univariate multiquadric quasi-interpolation scheme to solve the one-dimensional nonlinear sine-Gordon equation that is related to many physical phenomena. We obtain a numerical scheme by using the derivative of the quasi-interpolation to approximate the spatial derivative and a difference scheme to approximate the temporal derivative. The advantage of the obtained scheme is that the algorithm is very simple so that it is very easy to implement. The results of numerical experiments are presented and compared with analytical solutions to confirm the good accuracy of the presented scheme. 展开更多
关键词 QUASI-INTERPOLATION Hardy multiquadric (MQ) interpolation methods sine-Gordon equations scattered data approximation meshless method
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Improved geologic surface approximation using a multiquadric method with additional constraints 被引量:2
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作者 SONG Xianfeng RUI Xiaoping +1 位作者 JU Yiwen YANG Yongguo 《Mining Science and Technology》 EI CAS 2010年第4期600-606,共7页
Geologic surface approximation is profoundly affected by the presence, density and location of scattered geologic input data. Many studies have recognized the importance of utilizing varied sources of information when... Geologic surface approximation is profoundly affected by the presence, density and location of scattered geologic input data. Many studies have recognized the importance of utilizing varied sources of information when reconstructing a surface. This paper presents an improved geologic surface approximation method using a multiquadric function and borehole data. Additional information, i.e., inequality elevation and dip-strikes data extracted from outcrops or mining faces, is introduced in the form of physical constraints that control local changes in the estimated surface. Commonly accepted hypothesis states that geologic surfaces can be approximated to any desired degree of exactness by the summation of regular, mathematically defined, surfaces: in particular displaced quadric forms. The coefficients of the multiquadric functions are traditionally found by a least squares method. The addition of physical constraints in this work makes such an approach into a non-deterministic polynomial time problem. Hence we propose an objective function that represents the quality of the estimated surface and that includes the additional constraints by incorporation of a penalty function. Maximizing the smoothness of the estimated surface and its fitness to the additional constraints then allows the coefficients of the multiquadric function to be obtained by iterative methods. This method was implemented and demonstrated using data collected from the 81'st coal mining area of the Huaibei Coal Group. 展开更多
关键词 geologic surface spatial interpolation multiquadric function exterior penalty function physical constraints
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Multiquadric Radial Basis Function Approximation Scheme for Solution of Total Variation Based Multiplicative Noise Removal Model 被引量:1
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作者 Mushtaq Ahmad Khan Ahmed BAltamimi +4 位作者 Zawar Hussain Khan Khurram Shehzad Khattak Sahib Khan Asmat Ullah Murtaza Ali 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期55-88,共34页
This article introduces a fastmeshless algorithm for the numerical solution nonlinear partial differential equations(PDE)by Radial Basis Functions(RBFs)approximation connected with the Total Variation(TV)-basedminimiz... This article introduces a fastmeshless algorithm for the numerical solution nonlinear partial differential equations(PDE)by Radial Basis Functions(RBFs)approximation connected with the Total Variation(TV)-basedminimization functional and to show its application to image denoising containing multiplicative noise.These capabilities used within the proposed algorithm have not only the quality of image denoising,edge preservation but also the property of minimization of staircase effect which results in blocky effects in the images.It is worth mentioning that the recommended method can be easily employed for nonlinear problems due to the lack of dependence on a mesh or integration procedure.The numerical investigations and corresponding examples prove the effectiveness of the recommended algorithm regarding the robustness and visual improvement as well as peak-signal-to-noise ratio(PSNR),signal-to-noise ratio(SNR),and structural similarity index(SSIM)corresponded to the current conventional TV-based schemes. 展开更多
关键词 Denoised image multiplicative and speckle noises total variation(TV)filter Euler-Lagrange restoration equation multiquadric radial basis functions meshless and mesh-based schemes
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The Application of Multiquadric Function Fitting to Borehole Strain Time Series Data Processing 被引量:1
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作者 Peng Zhao Zhang Lei +1 位作者 Chen Zhiyao Lv Pingji 《Earthquake Research in China》 CSCD 2017年第2期239-246,共8页
Based on the existing continuous borehole strain observation,the multiquadric function fitting method was used to deal with time series data. The impact of difference kernel function parameters was discussed to obtain... Based on the existing continuous borehole strain observation,the multiquadric function fitting method was used to deal with time series data. The impact of difference kernel function parameters was discussed to obtain a valuable fitting result,from which the physical connotation of the original data and its possible applications were analyzed.Meanwhile,a brief comparison was made between the results of multiquadric function fitting and polynomial fitting. 展开更多
关键词 multiquadric function fitting Kernel function Borehole strain time series
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Generator,multiquadric generator,quasi-interpolation and multiquadric quasi-interpolation
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作者 WU Zong-min MA Li-min 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第4期390-400,共11页
The aim of this survey paper is to propose a new concept "generator". In fact, generator is a single function that can generate the basis as well as the whole function space. It is a more fundamental concept than ba... The aim of this survey paper is to propose a new concept "generator". In fact, generator is a single function that can generate the basis as well as the whole function space. It is a more fundamental concept than basis. Various properties of generator are also discussed. Moreover, a special generator named multiquadric function is introduced. Based on the multiquadric generator, the multiquadric quasi-interpolation scheme is constructed, and furthermore, the properties of this kind of quasi-interpolation are discussed to show its better capacity and stability in approximating the high order derivatives. 展开更多
关键词 GENERATOR function representation approximation numerical differentiation multiquadric quasi-interpolation
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Undersea Buried Pipeline Reconstruction Based on the Level Set and Inverse Multiquadric Regularization Method
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作者 SHANG Wenjing XUE Wei +2 位作者 XU Yidong MAKAROV Sergey B LI Yingsong 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第1期101-112,共12页
The electric inversion technique reconstructs the subsurface medium distribution from acquired data.On the basis of electric inversion,objects buried under the earth or seabed,such as pipelines and unexploded ordnance... The electric inversion technique reconstructs the subsurface medium distribution from acquired data.On the basis of electric inversion,objects buried under the earth or seabed,such as pipelines and unexploded ordnance,are detected and located in a contactless manner.However,the process of accurately reconstructing the shape of the target object is challenging because electric inversion is a nonlinear and ill-posed problem.In this work,we present an inverse multiquadric(IMQ)regularization method based on the level set function for reconstructing buried pipelines.In the case of locating underwater objects,the unknown inversion area is split into two parts,the background and the pipeline with known conductivity.The geometry of the pipeline is represented based on the level set function for achieving a noiseless inversion image.To obtain a binary image,the IMQ is used as the regularization term,which‘pushes’the level set function away from 0.We also provide an appropriate method to select the bandwidth and regularization parameters for the IMQ regularization term,resulting in reconstructed images with sharp edges.The simulation results and analysis show that the proposed method performs better than classical inversion methods. 展开更多
关键词 inverse problems level set function inverse multiquadric regularization method buried pipeline
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THE SHAPE PRESERVING AND HIGHACCURACYAPPROXIMATIONWITHMULTIQUADRIC
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《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第2期217-224,共8页
THESHAPEPRESERVINGANDHIGHACCURACYAPPROXIMATIONWITHMULTIQUADRIC*WUZONGMINANDLIUJIANPINAbstract.Thispaperdiscu... THESHAPEPRESERVINGANDHIGHACCURACYAPPROXIMATIONWITHMULTIQUADRIC*WUZONGMINANDLIUJIANPINAbstract.Thispaperdiscussesthesuficientc... 展开更多
关键词 multiquadric 保型高精度逼近 数值逼近理论 充分条件 拟插值
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A Comprehensive Price Prediction System Based on Inverse Multiquadrics Radial Basis Function for Portfolio Selection
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作者 Mengmeng Zheng 《Applied Mathematics》 2021年第12期1189-1209,共21页
Price prediction plays a crucial role in portfolio selection (PS). However, most price prediction strategies only make a single prediction and do not have efficient mechanisms to make a comprehensive price prediction.... Price prediction plays a crucial role in portfolio selection (PS). However, most price prediction strategies only make a single prediction and do not have efficient mechanisms to make a comprehensive price prediction. Here, we propose a comprehensive price prediction (CPP) system based on inverse multiquadrics (IMQ) radial basis function. First, the novel radial basis function (RBF) system based on IMQ function rather than traditional Gaussian (GA) function is proposed and centers on multiple price prediction strategies, aiming at improving the efficiency and robustness of price prediction. Under the novel RBF system, we then create a portfolio update strategy based on kernel and trace operator. To assess the system performance, extensive experiments are performed based on 4 data sets from different real-world financial markets. Interestingly, the experimental results reveal that the novel RBF system effectively realizes the integration of different strategies and CPP system outperforms other systems in investing performance and risk control, even considering a certain degree of transaction costs. Besides, CPP can calculate quickly, making it applicable for large-scale and time-limited financial market. 展开更多
关键词 Comprehensive Price Prediction Portfolio Selection (PS) Inverse multiquadrics (IMQ) Radial Basis Function
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Two to Six Dimensional Numerical Solutions to the Poisson Eigenvalue Partial Differential Equation Using Generalized Multiquadrics
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作者 Edward J.Kansa Pavel Holobvorodko 《American Journal of Computational Mathematics》 2025年第2期165-173,共9页
We solve numerically an eigenvalue elliptic partial differential equation(PDE)ranging from two to six dimensions using the generalized multiquadric(GMQ)radial basis functions(RBFs).Two discretization methods are em-pl... We solve numerically an eigenvalue elliptic partial differential equation(PDE)ranging from two to six dimensions using the generalized multiquadric(GMQ)radial basis functions(RBFs).Two discretization methods are em-ployed.The first method is similar to the classic mesh-based discretization method requiring n centers per dimension or a total ndpoints.The second method is based upon n randomly generated points in dℜrequiring far fewer data centers than the classic mesh method.Instead of having a crisp boundary,we form a“fuzzy”boundary.Using the analytic or numerical in-verse interior and boundary operators,we find the local and global minima and maxima to cull discretization points.We also find that the GMQ-RBF“flatness”can be controlled by increasing the GMQ exponential,β.We per-form a search to find the smallest root mean squared error(RMSE)by varying the exponent,the maximum,the minimum range of the GMQ shape parame-ter,and boundary influence,with the exponential having the most influence.Because the GMQ-RBFs are essentially nonlinear,it follows that the starting point of the simple search influences the end result.The optimal algorithm for high dimensional PDEs is still the subject of much research and may wait for the common place availability of massively parallel quantum computers for even higher dimensional PDEs and integral equations(IEs). 展开更多
关键词 Arbitrary Precision Arithmetic Elliptic Partial Differential Equations multiquadric Radial Basis Functions Solutions in Two-To-Six-Dimensional Space Uniformly Meshed and Fuzzy Boundaries Randomly Generated Points
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高精度积分值型MQ拟插值
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作者 张俊妮 彭兴璇 邵烁童 《应用数学进展》 2025年第5期540-553,共14页
本文针对积分值条件下的拟插值问题,提出了一种基于Multiquadric (MQ)函数的新型高精度数值逼近方法。作为一类条件正定径向基函数,MQ函数凭借其指数级收敛特性在拟插值理论中具有重要的应用价值。现有的MQ拟插值方法主要基于函数值,在... 本文针对积分值条件下的拟插值问题,提出了一种基于Multiquadric (MQ)函数的新型高精度数值逼近方法。作为一类条件正定径向基函数,MQ函数凭借其指数级收敛特性在拟插值理论中具有重要的应用价值。现有的MQ拟插值方法主要基于函数值,在实际应用中,函数信息经常以连续区间上的积分值形式呈现,本文重点解决仅知积分值条件下的构造问题。具体地,首先基于积分值的线性组合实现对节点处函数值及二阶导数值的逼近,进而结合利用函数值与二阶导数信息的拟插值方法,构造出新型的高精度积分值型MQ拟插值算子并推导了相应的误差估计表达式。数值实验结果表明,该方法有较好的逼近效果且其数值收敛阶与理论分析是吻合的,验证了所提算法的有效性。This paper proposes a novel high-precision numerical approximation method for quasi-interpolation problems under integral value conditions, utilizing Multiquadric (MQ) functions. As a class of conditionally positive definite radial basis functions, MQ functions hold significant application value in quasi-interpolation theory due to their exponential convergence properties. Existing MQ quasi-interpolation methods primarily rely on function values;however, in practical scenarios, functional information is often presented in the form of integral values over continuous intervals. This work focuses on addressing the construction of quasi-interpolation operators under the condition of known integral values. Specifically, we first approximate the function values and second-order derivative values at nodes through linear combinations of integral values. Subsequently, by integrating a quasi-interpolation framework that incorporates both function values and second-order derivative information, a novel high-precision integral-value-based MQ quasi-interpolation operator is constructed, accompanied by derived error estimation formulas. Numerical experiments demonstrate the favorable approximation performance of the proposed method, with the numerical convergence order aligning well with theoretical analyses, thereby validating the effectiveness of the algorithm. 展开更多
关键词 拟插值 multiquadric (MQ)函数 积分值 误差估计
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Multiquadric拟插值对高阶导数逼近的稳定性分析 谨以此文致《中国科学》创刊六十周年 被引量:1
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作者 马利敏 吴宗敏 《中国科学:数学》 CSCD 北大核心 2010年第12期1197-1204,共8页
基于样本数据来数值模拟函数的高阶导数是数值逼近中遇到的一类重要而且基本的问题,差商方法是数值微分的传统方法.但是在实际问题的求解中,它表现出强烈的不稳定性.在实际应用中,由于差商计算的不稳定性,它仅能用来模拟函数的低阶导数... 基于样本数据来数值模拟函数的高阶导数是数值逼近中遇到的一类重要而且基本的问题,差商方法是数值微分的传统方法.但是在实际问题的求解中,它表现出强烈的不稳定性.在实际应用中,由于差商计算的不稳定性,它仅能用来模拟函数的低阶导数.为了更好地模拟函数的高阶导数,本文利用multiquadric拟插值提出了一种新的方法.并将multiquadric拟插值方法模拟函数导数的稳定性与传统差商方法所得结果进行了对比.数值例子很好地验证了本文的理论.从理论论证和数值例子比较来看,multiquadric拟插值方法比差商方法更为稳定.这个性质也表明,基于散乱甚至有干扰的数据,在逼近函数的高阶导数时,multiquadric拟插值方法是一个有效的工具. 展开更多
关键词 径向基函数(RBFs) Hardy’s multiquadric(MQ) 拟插值 差商方法 白噪声 期望 方差
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Stability of multiquadric quasi-interpolation to approximate high order derivatives 被引量:5
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作者 MA LiMin 1,2 & WU ZongMin 1,1 Shanghai Key Laboratory for Contemporary Applied Mathematics,School of Mathematical Sciences,Fudan University,Shanghai 200433,China 2 Department of Information and Computer Science,Zhejiang Gongshang University,Hangzhou 310018,China 《Science China Mathematics》 SCIE 2010年第4期985-992,共8页
Numerical simulation of the high order derivatives based on the sampling data is an important and basic problem in numerical approximation,especially for solving the differential equations numerically.The classical me... Numerical simulation of the high order derivatives based on the sampling data is an important and basic problem in numerical approximation,especially for solving the differential equations numerically.The classical method is the divided difference method.However,it has been shown strongly unstable in practice.Actually,it can only be used to simulate the lower order derivatives in applications.To simulate the high order derivatives,this paper suggests a new method using multiquadric quasi-interpolation.The stability of the multiquadric quasi-interpolation method is compared with the classical divided difference method.Moreover,some numerical examples are presented to confirm the theoretical results.Both theoretical results and numerical examples show that the multiquadric quasi-interpolation method is much stabler than the divided difference method.This property shows that multiquadric quasi-interpolation method is an efficient tool to construct an approximation of high order derivatives based on scattered sampling data even with noise. 展开更多
关键词 numerical differential radial basis functions (RBFs) Hardy’s multiquadric (MQ) quasiinterpolation divided difference method white noise EXPECTATION variance
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A MULTIVARIATE MULTIQUADRIC QUASI-INTERPOLATION WITH QUADRIC REPRODUCTION 被引量:3
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作者 Renzhong Feng Xun Zhou 《Journal of Computational Mathematics》 SCIE CSCD 2012年第3期311-323,共13页
In this paper, by using multivariate divided differences to approximate the partial derivative and superposition, we extend the multivariate quasi-interpolation scheme based on dimension-splitting technique which can ... In this paper, by using multivariate divided differences to approximate the partial derivative and superposition, we extend the multivariate quasi-interpolation scheme based on dimension-splitting technique which can reproduce linear polynomials to the scheme quadric polynomials. Furthermore, we give the approximation error of the modified scheme. Our multivariate multiquadric quasi-interpolation scheme only requires information of lo- cation points but not that of the derivatives of approximated function. Finally, numerical experiments demonstrate that the approximation rate of our scheme is significantly im- proved which is consistent with the theoretical results. 展开更多
关键词 QUASI-INTERPOLATION multiquadric functions Polynomial reproduction :Pn-exact A-discretization of :Da Approximation error.
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Applying Multiquadric Quasi-Interpolation to Solve KdV Equation 被引量:1
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作者 Min Lu XIAO Ren Hong WANG Chun Gang ZHU 《Journal of Mathematical Research and Exposition》 CSCD 2011年第2期191-201,共11页
Quasi-interpolation is very useful in the study of approximation theory and its applications,since it can yield solutions directly without the need to solve any linear system of equations.Based on the good performance... Quasi-interpolation is very useful in the study of approximation theory and its applications,since it can yield solutions directly without the need to solve any linear system of equations.Based on the good performance,Chen and Wu presented a kind of multiquadric (MQ) quasi-interpolation,which is generalized from the L D operator,and used it to solve hyperbolic conservation laws and Burgers’ equation.In this paper,a numerical scheme is presented based on Chen and Wu’s method for solving the Korteweg-de Vries (KdV) equation.The presented scheme is obtained by using the second-order central divided difference of the spatial derivative to approximate the third-order spatial derivative,and the forward divided difference to approximate the temporal derivative,where the spatial derivative is approximated by the derivative of the generalized L D quasi-interpolation operator.The algorithm is very simple and easy to implement and the numerical experiments show that it is feasible and valid. 展开更多
关键词 KdV equation multiquadric(MQ) quasi-interpolation numerical solution
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一种新的积分值型MQ拟插值算子
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作者 常雪 彭兴璇 《应用数学进展》 2024年第9期4144-4151,共8页
Multiquadric (MQ)函数作为径向基函数的一种,其作为核函数可逼近任何光滑函数,被广泛应用在拟插值的研究中,现有的MQ拟插值大部分都是以离散函数值为已知条件,而在实际应用中,积分值作为已知条件也比较常见,为了让MQ拟插值得到更广泛... Multiquadric (MQ)函数作为径向基函数的一种,其作为核函数可逼近任何光滑函数,被广泛应用在拟插值的研究中,现有的MQ拟插值大部分都是以离散函数值为已知条件,而在实际应用中,积分值作为已知条件也比较常见,为了让MQ拟插值得到更广泛的应用,本文提出了一种新的基于积分值的MQ拟插值算子。首先利用连续区间上积分值的线性组合来对节点处的导数值进行逼近,然后根据已有的MQ拟插值进一步得到新的积分值型MQ拟插值算子,并给出了误差估计。最后通过数值实验展示了本文构造的积分值型MQ拟插值算子的逼近效果,说明了该方法的可行性和有效性。As a kind of radial basis function, Multiquadric (MQ) function, as a kernel function, can approximate any smooth function, and is widely used in the research of quasi-interpolation. Most of the existing MQ quasi-interpolation is based on the known condition of the discrete function value, and in practical applications, the integral value is also a common-known condition. In order to make MQ quasi-interpolation more widely used, a new MQ quasi-interpolation operator based on integral value is proposed in this paper. First, the derivative value at the node is approximated by the linear combination of integral values on the continuous interval, and then a new integral value MQ quasi-interpolation operator is obtained according to the existing MQ quasi-interpolation, and the error estimate is given. Finally, the approximation effect of the integral-valued MQ quasi-interpolation operator constructed in this paper is demonstrated by numerical experiments, and the feasibility and effectiveness of the proposed method are demonstrated. 展开更多
关键词 multiquadric函数 积分值 拟插值 误差估计
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