{"title":"Hybrid meshless method for solving inhomogeneous polyharmonic equations","authors":"C.S. Chen , Andreas Karageorghis , Q.G. Liu","doi":"10.1016/j.camwa.2025.07.023","DOIUrl":"10.1016/j.camwa.2025.07.023","url":null,"abstract":"<div><div>We employ the method of particular solutions in the numerical solution of boundary value problems for inhomogeneous polyharmonic equations in two and three dimensions. An approximate particular solution of the governing partial differential equation is calculated using the radial basis function collocation method while the resulting homogeneous problems are solved using the method of fundamental solutions. The results of several numerical experiments demonstrate the efficacy of the proposed approach.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"196 ","pages":"Pages 218-232"},"PeriodicalIF":2.9,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679046","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}
{"title":"U-shaped factorized Fourier neural operator for solving partial differential equations","authors":"Hui Liu, Peizhi Zhao, Tao Song","doi":"10.1016/j.camwa.2025.07.013","DOIUrl":"10.1016/j.camwa.2025.07.013","url":null,"abstract":"<div><div>In this study, we proposed a U-shaped Factorized Fourier neural operator (U-FFNO) by introducing the U-shaped architecture idea and skip connection method of U-Net and improving the F-FNO operator layer using a Gaussian low-pass filter. The Factorized Fourier neural operator (F-FNO) introduces a dimensional decomposition method to learn the nonlinear mapping from parameter space to solution space to solve a series of partial differential equations (PDEs). However, due to the existence of truncation coefficients, some high-frequency information will be lost in the process of learning the nonlinear mapping, resulting in an increase in the error when learning the solution space. The proposed U-FFNO can learn this part of the information before the high-frequency information is lost, and enhances the learning ability of low-frequency information. We conduct experiments on several challenging partial differential equations in regular grids and structured grids to demonstrate the excellent accuracy of U-FFNO. U-FFNO is a learning-based method for simulating partial differential equations. As a neural operator, it also has the characteristics of discretization invariance and still performs well in super-resolution prediction tasks.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"196 ","pages":"Pages 233-245"},"PeriodicalIF":2.9,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686862","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}
Jiangong Pan , Wei Wan , Chenlong Bao , Zuoqiang Shi
{"title":"Solving unbalanced optimal transport on point cloud by tangent radial basis function method","authors":"Jiangong Pan , Wei Wan , Chenlong Bao , Zuoqiang Shi","doi":"10.1016/j.camwa.2025.07.015","DOIUrl":"10.1016/j.camwa.2025.07.015","url":null,"abstract":"<div><div>In this paper, we solve unbalanced optimal transport (UOT) problem on surfaces represented by point clouds. Based on alternating direction method of multipliers algorithm, the original UOT problem can be solved by an iteration consists of three steps. The key ingredient is to solve a Poisson equation on point cloud which is solved by tangent radial basis function (TRBF) method. The proposed TRBF method requires only the point cloud and normal vectors to discretize the Poisson equation which simplify the computation significantly. Numerical experiments conducted on point clouds with varying geometry and topology demonstrate the effectiveness of the proposed method.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"195 ","pages":"Pages 161-176"},"PeriodicalIF":2.9,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679259","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}
{"title":"A novel numerical method for solving a two-dimensional variable-order time fractional advection-diffusion problem","authors":"Saurabh Kumar , Vikas Gupta , Ajay Kumar","doi":"10.1016/j.camwa.2025.07.025","DOIUrl":"10.1016/j.camwa.2025.07.025","url":null,"abstract":"<div><div>The convection-diffusion equation describes the transport of physical quantities such as particles, energy, and pollutants by incorporating both diffusion and convection phenomena. In this study, a numerical method is proposed to approximate solutions to the two-dimensional variable-order time fractional advection-diffusion equation (VO-TFADE). The method combines Taylor's functions and two-dimensional Laguerre polynomials to approximate the temporal and spatial components. Caputo's fractional derivative definition is applied, with the fractional derivatives being approximated using an operational matrix of differentiation. The problem is then transformed into a system of algebraic equations. Additionally, the error bound for the proposed method is provided. Numerical examples validate the accuracy and efficiency of the approach.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"195 ","pages":"Pages 177-190"},"PeriodicalIF":2.9,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679258","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}
{"title":"Analysis of H1 penalized fictitious domain method for parabolic problems","authors":"Swapnil Kale , Debasish Pradhan , Sarvesh Kumar","doi":"10.1016/j.camwa.2025.07.009","DOIUrl":"10.1016/j.camwa.2025.07.009","url":null,"abstract":"<div><div>This work focuses on establishing optimal <em>a priori</em> error estimates and stability analysis for <span><math><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span> penalized fictitious domain method for parabolic problems defined over curved complex domains. We embed the given complicated domain Ω into a larger rectangular domain R and extend the governing equation to a rectangular domain R by employing penalty parameter <em>ϵ</em> in the fictitious part <span><math><mi>R</mi><mo>﹨</mo><mi>Ω</mi></math></span>. Considering the inherent characteristic of the <span><math><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span> penalty, in the variational formulation, we impose the <span><math><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span> penalty only on the elliptic part and evince that the solution of the new penalized problem converges to the original solution. In order to obtain a numerical solution to the penalized problem, for spatial discretization, we utilize linear-finite elements on structured triangular mesh irrespective of the shape of the domain, and an Euler backward scheme is employed for the discretization of time space. Convergence analysis and discrete stability estimates are derived for semi and fully-discrete schemes. Moreover, numerical experiments are accomplished to validate the theoretical convergence rate and examine the computational efficiency of the proposed method.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"196 ","pages":"Pages 183-200"},"PeriodicalIF":2.9,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679087","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}
{"title":"Spatiotemporal dynamics deduced by nonlocal delay competition in a diffusive Lotka-Volterra population model","authors":"Xiaosong Tang , Jiaxin Shen , Xinchang Wang , Zhaoyun Zeng , Jingwen Zhu","doi":"10.1016/j.camwa.2025.07.008","DOIUrl":"10.1016/j.camwa.2025.07.008","url":null,"abstract":"<div><div>In this article, under the influence of nonlocal delay competition, we are devoted to investigating spatiotemporal dynamics of a diffusive Lotka-Volterra population model. According to the different values of some parameters, the original model may be changed into Lotka-Volterra predator-prey model, cooperative population model, or competition population model. Then, through the characteristic equation analysis, we find that nonlocal delay competition can deduce the presence of Turing-Hopf bifurcation when the original model is Lotka-Volterra cooperative population model or competition population model. However, when the original model is Lotka-Volterra predator-prey model, nonlocal delay competition cannot deduce the presence of Turing-Hopf bifurcation, but delay can deduce stability switches and the presence of Hopf bifurcation. Moreover, in the known literatures, to our knowledge, reaction-diffusion model with nonlocal delay competition has been investigated more rarely, which implies that our results in this paper are new. Finally, by presenting some numerical calculations and simulations, we obtain the rich results of stable spatially homogeneous periodic solutions, spatially steady state solutions, spatially inhomogeneous periodic solutions and stability switches deduced by delay.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"196 ","pages":"Pages 172-182"},"PeriodicalIF":2.9,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679086","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}
{"title":"Physics-constrained deep kernel learning for inverse problems with noisy data","authors":"Zhenjie Tang, Li He","doi":"10.1016/j.camwa.2025.07.022","DOIUrl":"10.1016/j.camwa.2025.07.022","url":null,"abstract":"<div><div>We propose a novel physics-constrained deep kernel learning (PCDKL) to estimate physical parameters and learn forward solutions for problems described by partial differential equations (PDEs) and noisy data. In this framework, a Gaussian Process (GP) with a deep kernel is constructed to model the forward solution. The posterior function samples from the GP serve as surrogates for the PDE solution. These GP posterior samples are constrained by two likelihoods: one to fit the noisy observations and the other to enforce conformity with the governing equation. To efficiently and effectively infer the deep kernel and physical parameters, we develop a stochastic estimation algorithm based on the evidence lower bound (ELBO), which serves as a posterior regularization objective function. The effectiveness of the proposed PCDKL is demonstrated through a systematic comparison with a Bayesian physics-informed neural network (B-PINN), a state-of-the-art method for solving inverse problems in PDEs with noisy observations. Our experiments show that PCDKL not only achieves forward solutions with informative uncertainty estimates comparable to B-PINN, but also yields accurate estimates of physical parameters. These results suggest that PCDKL has significant potential for uncertainty quantification in forward solutions and accurate physical parameter estimation, making it valuable for practical applications.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"196 ","pages":"Pages 135-150"},"PeriodicalIF":2.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144670241","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}
Cai Mingchao , Li Jingzhi , Li Ziliang , Liu Qiang
{"title":"An efficient iterative decoupling method for thermo-poroelasticity based on a four-field formulation","authors":"Cai Mingchao , Li Jingzhi , Li Ziliang , Liu Qiang","doi":"10.1016/j.camwa.2025.07.021","DOIUrl":"10.1016/j.camwa.2025.07.021","url":null,"abstract":"<div><div>This paper studies the thermo-poroelasticity model. By introducing an intermediate variable, we transform the original three-field model into a four-field model. Building upon this four-field model, we present both a coupled finite element method and a decoupled iterative finite element method. We prove the stability and optimal convergence of the coupled finite element method. Furthermore, we establish the convergence of the decoupled iterative method. This paper focuses primarily on analyzing the iterative decoupled algorithm. It demonstrates that the algorithm's convergence does not require any additional assumptions about physical parameters or stabilization parameters. Numerical results are provided to demonstrate the effectiveness and theoretical validity of these new methods.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"195 ","pages":"Pages 139-160"},"PeriodicalIF":2.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144671079","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}
{"title":"A family of even-order edge-oriented nonconforming finite elements in 2D with efficient locally conservative flux reconstruction","authors":"Gwanghyun Jo , Hyeokjoo Park","doi":"10.1016/j.camwa.2025.07.024","DOIUrl":"10.1016/j.camwa.2025.07.024","url":null,"abstract":"<div><div>In this paper, we propose a new family of edge-oriented even-order nonconforming finite elements in 2D. The proposed element has fewer degrees of freedom compared to the existing edge-oriented nonconforming elements, and preserves some attractive properties of the Crouzeix-Raviart element, such as the optimal approximation capability and the inf-sup stability. We also present an efficient <span><math><mi>H</mi><mo>(</mo><mi>div</mi><mo>)</mo></math></span>-conforming flux reconstruction for the finite element discretization by the proposed element, which is possible due to its edge-oriented degrees of freedom.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"196 ","pages":"Pages 127-134"},"PeriodicalIF":2.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144672318","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}
{"title":"Vertex-centered control-volume mimetic finite difference methods","authors":"Rainer Helmig , Martin Schneider , Ivan Yotov","doi":"10.1016/j.camwa.2025.07.018","DOIUrl":"10.1016/j.camwa.2025.07.018","url":null,"abstract":"<div><div>We develop a new class of vertex-centered control-volume mimetic finite difference methods on polytopal meshes for second order elliptic equations. The schemes are based on a mixed velocity-pressure formulation. The pressure is constant on dual mesh control-volumes constructed around the primary mesh vertices. The normal velocity is constant on the faces of the control-volumes, resulting in local mass conservation over the control-volumes. We consider both symmetric velocity integration rules constructed over the control-volumes, as well as non-symmetric quadrature rules constructed over sub-volumes obtained by the intersection of primary and dual elements. The latter choice allows for explicit gradient construction and local multipoint flux elimination within the primary elements, resulting in a positive definite vertex-centered pressure system. On simplicial, quadrilateral or hexahedral meshes, these local flux methods are closely related, and in some cases equivalent, to the classical vertex-centered control-volume finite element methods based on piecewise polynomial finite element basis functions for the pressure. The mimetic finite difference framework is utilized to analyze the well posedness and accuracy of the proposed methods. We establish first order convergence for the pressure and the velocity in the discrete mimetic norms, as well as second order pressure superconvergence in the case of symmetric quadrature rules. A series of numerical experiments illustrates the convergence properties of the methods on problems with varying degree of anisotropy, heterogeneity, and grid complexity in two and three dimensions.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"196 ","pages":"Pages 104-126"},"PeriodicalIF":2.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144672322","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}