Journal of Scientific Computing最新文献

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Sine Transform Based Preconditioning for an Inverse Source Problem of Time-Space Fractional Diffusion Equations 基于正弦变换的时空分形扩散方程反源问题预处理
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-25 DOI: 10.1007/s10915-024-02634-x
Hong-Kui Pang, Hai-Hua Qin, Shuai Ni
{"title":"Sine Transform Based Preconditioning for an Inverse Source Problem of Time-Space Fractional Diffusion Equations","authors":"Hong-Kui Pang, Hai-Hua Qin, Shuai Ni","doi":"10.1007/s10915-024-02634-x","DOIUrl":"https://doi.org/10.1007/s10915-024-02634-x","url":null,"abstract":"<p>We investigate an inverse problem with quasi-boundary value regularization for reconstructing a source term of time-space fractional diffusion equations from the final observation. A sine transform based preconditioning technique is developed for the linear system which arises from the finite difference discretization of the regularized problem. By making use of the special structure, the proposed preconditioner can be inverted efficiently by the fast sine transform and fast Fourier transform. Theoretically, we show that the preconditioned matrix can be written as the sum of two matrices. The eigenvalues of one matrix are located within a rectangular domain which is uniformly bounded away from zero. Moreover, the boundaries of the domain are independent of grid numbers, regularization parameter, and the noise level. The other matrix has rank less than twice the number of spatial grids but is independent of the number of temporal grids. Numerical experiments are performed to verify the effectiveness of the proposed preconditioner.</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"54 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141776665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Unbalanced Optimal Transport and Maximum Mean Discrepancies: Interconnections and Rapid Evaluation 非平衡最优传输和最大均值差异:相互联系与快速评估
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-24 DOI: 10.1007/s10915-024-02586-2
Rajmadan Lakshmanan, Alois Pichler
{"title":"Unbalanced Optimal Transport and Maximum Mean Discrepancies: Interconnections and Rapid Evaluation","authors":"Rajmadan Lakshmanan, Alois Pichler","doi":"10.1007/s10915-024-02586-2","DOIUrl":"https://doi.org/10.1007/s10915-024-02586-2","url":null,"abstract":"<p>This contribution presents substantial computational advancements to compare measures even with varying masses. Specifically, we utilize the nonequispaced fast Fourier transform to accelerate the radial kernel convolution in unbalanced optimal transport approximation, built upon the Sinkhorn algorithm. We also present accelerated schemes for maximum mean discrepancies involving kernels. Our approaches reduce the arithmetic operations needed to compute distances from <span>({{mathcal {O}}}left( n^{2}right) )</span> to <span>({{{mathcal {O}}}}left( n log n right) )</span>, opening the door to handle large and high-dimensional datasets efficiently. Furthermore, we establish robust connections between transportation problems, encompassing Wasserstein distance and unbalanced optimal transport, and maximum mean discrepancies. This empowers practitioners with compelling rationale to opt for adaptable distances.\u0000</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"22 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141776716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Correction of a High-Order Numerical Method for Approximating Time-Fractional Wave Equation 修正用于逼近时分数波方程的高阶数值方法
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-22 DOI: 10.1007/s10915-024-02625-y
M. Ramezani, R. Mokhtari, Y. Yan
{"title":"Correction of a High-Order Numerical Method for Approximating Time-Fractional Wave Equation","authors":"M. Ramezani, R. Mokhtari, Y. Yan","doi":"10.1007/s10915-024-02625-y","DOIUrl":"https://doi.org/10.1007/s10915-024-02625-y","url":null,"abstract":"<p>A high-order time discretization scheme to approximate the time-fractional wave equation with the Caputo fractional derivative of order <span>(alpha in (1, 2))</span> is studied. We establish a high-order formula for approximating the Caputo fractional derivative of order <span>(alpha in (1, 2))</span>. Based on this approximation, we propose a novel numerical method to solve the time-fractional wave equation. Remarkably, this method corrects only one starting step and demonstrates second-order convergence in both homogeneous and inhomogeneous cases, regardless of whether the data is smooth or nonsmooth. We also analyze the stability region associated with the proposed numerical method. Some numerical examples are given to elucidate the convergence analysis.\u0000</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"36 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141738114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Structure-Preserving Algorithm and Its Error Estimate for the Relativistic Charged-Particle Dynamics Under the Strong Magnetic Field 强磁场下相对论带电粒子动力学的结构保持算法及其误差估计
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-22 DOI: 10.1007/s10915-024-02618-x
Ruili Zhang, Tong Liu, Bin Wang, Jian Liu, Yifa Tang
{"title":"Structure-Preserving Algorithm and Its Error Estimate for the Relativistic Charged-Particle Dynamics Under the Strong Magnetic Field","authors":"Ruili Zhang, Tong Liu, Bin Wang, Jian Liu, Yifa Tang","doi":"10.1007/s10915-024-02618-x","DOIUrl":"https://doi.org/10.1007/s10915-024-02618-x","url":null,"abstract":"<p>This paper investigates the numerical algorithm and its error estimates for the dynamics of relativistic charged particles under a strong maximal ordering scaling magnetic field. To maintain the fundamental principles of relativistic dynamics, including energy conservation, volume preservation, and the Lorentz invariant property, we construct a structure-preserving algorithm using the splitting scheme. This algorithm ensures the preservation of volume, energy, and the Lorentz invariant property (VELPA) exactly. Specifically, we establish an uniform and optimal error bound in both 4-position and 4-velocity for VELPA. Numerical experiments are also presented to demonstrate the advantages of VELPA in both uniform error estimate and conservation of energy, compared to the implicit Euler method and traditional energy-preserving AVF method.</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"152 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141738112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Block Diagonalization of Block Circulant Quaternion Matrices and the Fast Calculation for T-Product of Quaternion Tensors 块环四元数矩阵的块对角化和四元张量 T 积的快速计算
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-21 DOI: 10.1007/s10915-024-02623-0
Meng-Meng Zheng, Guyan Ni
{"title":"Block Diagonalization of Block Circulant Quaternion Matrices and the Fast Calculation for T-Product of Quaternion Tensors","authors":"Meng-Meng Zheng, Guyan Ni","doi":"10.1007/s10915-024-02623-0","DOIUrl":"https://doi.org/10.1007/s10915-024-02623-0","url":null,"abstract":"<p>With quaternion matrices and quaternion tensors being gradually used in the color image and color video processing, the block diagonalization of block circulant quaternion matrices has become a key issue in the establishment of T-product based methods for quaternion tensors. Out of this consideration, we aim at establishing a fast calculation approach for the block diagonalization of block circulant quaternion matrices with the help of the fast Fourier transform (FFT). We first show that the discrete Fourier matrix <span>(mathbf {F_p})</span> cannot diagonalize <span>(ptimes p)</span> circulant quaternion matrices, nor can the unitary quaternion matrices <span>(mathbf {F_p}textbf{j})</span> and <span>(mathbf {F_p}(1+textbf{j})/sqrt{2})</span> with <span>(textbf{j})</span> being an imaginary unit of quaternion algebra. Then we prove that the unitary octonion matrix <span>(mathbf {F_p}textbf{p})</span> with <span>(textbf{p}=textbf{l},textbf{il})</span> or <span>((textbf{l}+textbf{il})/sqrt{2})</span> (<span>(textbf{l}, textbf{il})</span> being imaginary units of octonion algebra) can diagonalize a circulant quaternion matrix of size <span>(ptimes p)</span>, which further means that a block circulant quaternion matrix of size <span>(mptimes np)</span> can be block diagonalized at the cost of <span>(O(mnplog p))</span> via the FFT. As one of applications, we give a fast algorithm to speed up the calculation of the T-product between <span>(mtimes ntimes p)</span> and <span>(ntimes stimes p)</span> third-order quaternion tensors via FFTs, whose computational magnitude is almost 1/<i>p</i> of the original one. As another application, we propose an effective compression strategy for third-order quaternion tensors with a certain low-rankness. Simulations on the color image and color video compression demonstrate that our compression strategy with no QSVD involved, can achieve higher quality compression in terms of PSNR values at much less time costs, compared with the QSVD-based methods.</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"23 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141738109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On the Solution Existence for Collocation Discretizations of Time-Fractional Subdiffusion Equations 论时间-分数子扩散方程对位离散化的解存在性
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-18 DOI: 10.1007/s10915-024-02619-w
Sebastian Franz, Natalia Kopteva
{"title":"On the Solution Existence for Collocation Discretizations of Time-Fractional Subdiffusion Equations","authors":"Sebastian Franz, Natalia Kopteva","doi":"10.1007/s10915-024-02619-w","DOIUrl":"https://doi.org/10.1007/s10915-024-02619-w","url":null,"abstract":"<p>Time-fractional parabolic equations with a Caputo time derivative of order <span>(alpha in (0,1))</span> are discretized in time using continuous collocation methods. For such discretizations, we give sufficient conditions for existence and uniqueness of their solutions. Two approaches are explored: the Lax–Milgram Theorem and the eigenfunction expansion. The resulting sufficient conditions, which involve certain <span>(mtimes m)</span> matrices (where <i>m</i> is the order of the collocation scheme), are verified both analytically, for all <span>(mge 1)</span> and all sets of collocation points, and computationally, for all <span>( mle 20)</span>. The semilinear case is also addressed.\u0000</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"29 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141745966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Structure-Preserving Semi-implicit IMEX Finite Volume Scheme for Ideal Magnetohydrodynamics at all Mach and Alfvén Numbers 所有马赫数和阿尔弗文数下理想磁流体力学的保结构半隐式 IMEX 有限体积方案
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-17 DOI: 10.1007/s10915-024-02606-1
Walter Boscheri, Andrea Thomann
{"title":"A Structure-Preserving Semi-implicit IMEX Finite Volume Scheme for Ideal Magnetohydrodynamics at all Mach and Alfvén Numbers","authors":"Walter Boscheri, Andrea Thomann","doi":"10.1007/s10915-024-02606-1","DOIUrl":"https://doi.org/10.1007/s10915-024-02606-1","url":null,"abstract":"<p>We present a divergence-free semi-implicit finite volume scheme for the simulation of the ideal magnetohydrodynamics (MHD) equations which is stable for large time steps controlled by the local transport speed at all Mach and Alfvén numbers. An operator splitting technique allows to treat the convective terms explicitly while the hydrodynamic pressure and the magnetic field contributions are integrated implicitly, yielding two decoupled linear implicit systems. The linearity of the implicit part is achieved by means of a semi-implicit time linearization. This structure is favorable as second-order accuracy in time can be achieved relying on the class of semi-implicit IMplicit–EXplicit Runge–Kutta (IMEX-RK) methods. In space, implicit cell-centered finite difference operators are designed to discretely preserve the divergence-free property of the magnetic field on three-dimensional Cartesian meshes. The new scheme is also particularly well suited for low Mach number flows and for the incompressible limit of the MHD equations, since no explicit numerical dissipation is added to the implicit contribution and the time step is scale independent. Likewise, highly magnetized flows can benefit from the implicit treatment of the magnetic fluxes, hence improving the computational efficiency of the novel method. The convective terms undergo a shock-capturing second order finite volume discretization to guarantee the effectiveness of the proposed method even for high Mach number flows. The new scheme is benchmarked against a series of test cases for the ideal MHD equations addressing different acoustic and Alfvén Mach number regimes where the performance and the stability of the new scheme is assessed.</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"2012 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141719073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Mass-Conservative Reduced-Order Algorithm in Solving Optimal Control of Convection-Diffusion Equation 解决对流扩散方程优化控制的质量守恒降序算法
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-14 DOI: 10.1007/s10915-024-02620-3
Junpeng Song, Qiuqin Wu, Yi Shi
{"title":"A Mass-Conservative Reduced-Order Algorithm in Solving Optimal Control of Convection-Diffusion Equation","authors":"Junpeng Song, Qiuqin Wu, Yi Shi","doi":"10.1007/s10915-024-02620-3","DOIUrl":"https://doi.org/10.1007/s10915-024-02620-3","url":null,"abstract":"<p>This paper introduces a novel approach, the mass-conservative reduced-order characteristic finite element (MCROCFE) method, designed for optimal control problem governed by convection-diffusion equation. The study delves into scenarios where the original state equation exhibits mass-conservation, yet the velocity field is non-divergence-free. The key points of emphasis are: (1) The method effectively addresses convection-dominated diffusion systems through the application of the characteristic technique; (2) Its efficiency is underscored by leveraging the proper orthogonal decomposition (POD) technique, significantly reducing the scale of solving algebraic equation systems; (3) The proposed scheme, based on the mass-conservative characteristic finite element (MCCFE) method framework and the classical POD technique with a slight adjustment to reduce-order space, maintains mass-conservation for the state variable. A priori error estimates are derived for the mass-conservative reduced-order scheme. Theoretical results are validated through numerical comparisons with the MCCFE method, emphasizing the mass-conservation, accuracy and efficiency of the MCROCFE method.</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"108 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141609467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Preconditioned MINRES Method for Block Lower Triangular Toeplitz Systems 块下三角托普利兹系统的预处理 MINRES 方法
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-13 DOI: 10.1007/s10915-024-02611-4
Congcong Li, Xuelei Lin, Sean Hon, Shu-Lin Wu
{"title":"A Preconditioned MINRES Method for Block Lower Triangular Toeplitz Systems","authors":"Congcong Li, Xuelei Lin, Sean Hon, Shu-Lin Wu","doi":"10.1007/s10915-024-02611-4","DOIUrl":"https://doi.org/10.1007/s10915-024-02611-4","url":null,"abstract":"<p>In this study, a novel preconditioner based on the absolute-value block <span>(alpha )</span>-circulant matrix approximation is developed, specifically designed for nonsymmetric dense block lower triangular Toeplitz (BLTT) systems that emerge from the numerical discretization of evolutionary equations. Our preconditioner is constructed by taking an absolute-value of a block <span>(alpha )</span>-circulant matrix approximation to the BLTT matrix. To apply our preconditioner, the original BLTT linear system is converted into a symmetric form by applying a time-reversing permutation transformation. Then, with our preconditioner, the preconditioned minimal residual method (MINRES) solver is employed to solve the symmetrized linear system. With properly chosen <span>(alpha )</span>, the eigenvalues of the preconditioned matrix are proven to be clustered around <span>(pm 1)</span> without any significant outliers. With the clustered spectrum, we show that the preconditioned MINRES solver for the preconditioned system has a convergence rate independent of system size. The efficacy of the proposed preconditioner is corroborated by our numerical experiments, which reveal that it attains optimal convergence.</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"23 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141614425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Stability Analysis and Error Estimate of the Explicit Single-Step Time-Marching Discontinuous Galerkin Methods with Stage-Dependent Numerical Flux Parameters for a Linear Hyperbolic Equation in One Dimension 一维线性双曲方程的显式单步时间行进非连续伽勒金方法与阶段性数值通量参数的稳定性分析和误差估计
IF 2.5 2区 数学
Journal of Scientific Computing Pub Date : 2024-07-13 DOI: 10.1007/s10915-024-02621-2
Yuan Xu, Chi-Wang Shu, Qiang Zhang
{"title":"Stability Analysis and Error Estimate of the Explicit Single-Step Time-Marching Discontinuous Galerkin Methods with Stage-Dependent Numerical Flux Parameters for a Linear Hyperbolic Equation in One Dimension","authors":"Yuan Xu, Chi-Wang Shu, Qiang Zhang","doi":"10.1007/s10915-024-02621-2","DOIUrl":"https://doi.org/10.1007/s10915-024-02621-2","url":null,"abstract":"<p>In this paper, we present the <span>(hbox {L}^2)</span>-norm stability analysis and error estimate for the explicit single-step time-marching discontinuous Galerkin (DG) methods with stage-dependent numerical flux parameters, when solving a linear constant-coefficient hyperbolic equation in one dimension. Two well-known examples of this method include the Runge–Kutta DG method with the downwind treatment for the negative time marching coefficients, as well as the Lax–Wendroff DG method with arbitrary numerical flux parameters to deal with the auxiliary variables. The stability analysis framework is an extension and an application of the matrix transferring process based on the temporal differences of stage solutions, and a new concept, named as the averaged numerical flux parameter, is proposed to reveal the essential upwind mechanism in the fully discrete status. Distinguished from the traditional analysis, we have to present a novel way to obtain the optimal error estimate in both space and time. The main tool is a series of space–time approximation functions for a given spatial function, which preserve the local structure of the fully discrete schemes and the balance of exact evolution under the control of the partial differential equation. Finally some numerical experiments are given to validate the theoretical results proposed in this paper.</p>","PeriodicalId":50055,"journal":{"name":"Journal of Scientific Computing","volume":"36 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141614426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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