Applied Numerical Mathematics最新文献_第10页

The weak Galerkin finite element method for Stokes interface problems with curved interface 具有弯曲界面的Stokes界面问题的弱Galerkin有限元法

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.10.004

Lin Yang, Qilong Zhai, Ran Zhang

引用次数: 0

Penalty hyperparameter optimization with diversity measure for nonnegative low-rank approximation 非负低秩逼近的带有分集度量的惩罚超参数优化

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.10.002

Nicoletta Del Buono , Flavia Esposito , Laura Selicato , Rafał Zdunek

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引用次数: 0

An inverse problem of determining the parameters in diffusion equations by using fractional physics-informed neural networks 利用分数阶物理信息神经网络确定扩散方程参数的反问题

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.10.016

M. Srati , A. Oulmelk , L. Afraites , A. Hadri , M.A. Zaky , A. Aldraiweesh , A.S. Hendy

{"title":"An inverse problem of determining the parameters in diffusion equations by using fractional physics-informed neural networks","authors":"M. Srati , A. Oulmelk , L. Afraites , A. Hadri , M.A. Zaky , A. Aldraiweesh , A.S. Hendy","doi":"10.1016/j.apnum.2024.10.016","DOIUrl":"10.1016/j.apnum.2024.10.016","url":null,"abstract":"<div><div>In this study, we address an inverse problem in nonlinear time-fractional diffusion equations using a deep neural network. The challenge arises from the equation's nonlinear behavior, the involvement of time-based fractional Caputo derivatives, and the need to estimate parameters influenced by space or the solution of the fractional PDE. Our solution involves a fractional physics-informed neural network (FPINN). Initially, we use FPINN to solve a straightforward problem. Then, we apply FPINN to the inverse problem of estimating parameter and model non-linearity. For the inverse problem, we enhance our method by including the mean square error of final observations in the FPINN's cost function. This adjustment helps effectively in tackling the unique challenges of the time-fractional diffusion equation. Numerical tests involving regular and singular examples demonstrate the effectiveness of the physics-informed neural network approach in accurately recovering parameters. We reinforce this finding through a numerical comparison with alternative methods such as the alternating direction multiplier method (ADMM), the gradient descent, and the DeepONets (deep operator networks) method.</div></div>","PeriodicalId":8199,"journal":{"name":"Applied Numerical Mathematics","volume":"208 ","pages":"Pages 189-213"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141227","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

Two efficient iteration methods for solving the absolute value equations 求解绝对值方程的两种有效迭代方法

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.10.009

Xiaohui Yu , Qingbiao Wu

引用次数: 0

Regularisation and iterated regularisation of Hamiltonian systems of the second quasi-Painlevé equation 二阶拟painlevevl方程哈密顿系统的正则化与迭代正则化

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.10.012

Galina Filipuk

引用次数: 0

Orthogonal designs for computer experiments constructed from sequences with zero autocorrelation 由零自相关序列构建的计算机实验正交设计

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2023.09.010

Omar A. Alhelali , S.D. Georgiou , C. Koukouvinos , S. Stylianou

引用次数: 0

A new class of symplectic methods for stochastic Hamiltonian systems 随机哈密顿系统的新一类交映法

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.01.021

Cristina Anton

引用次数: 0

Krylov subspace methods for large multidimensional eigenvalue computation 用于大型多维特征值计算的克雷洛夫子空间方法

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.01.017

Anas El Hachimi , Khalide Jbilou , Ahmed Ratnani

引用次数: 0

Extrapolated splitting methods for multilinear PageRank computations 多线性PageRank计算的外推拆分方法

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2023.11.019

Maryam Boubekraoui

引用次数: 0

Implicit EXP-RBF techniques for modeling unsaturated flow through soils with water uptake by plant roots 隐式EXP-RBF技术模拟植物根系吸收土壤中的非饱和流动

IF 2.2 2区数学

Applied Numerical Mathematics Pub Date : 2025-02-01 DOI: 10.1016/j.apnum.2024.10.003

Mohamed Boujoudar , Abdelaziz Beljadid , Ahmed Taik

{"title":"Implicit EXP-RBF techniques for modeling unsaturated flow through soils with water uptake by plant roots","authors":"Mohamed Boujoudar , Abdelaziz Beljadid , Ahmed Taik","doi":"10.1016/j.apnum.2024.10.003","DOIUrl":"10.1016/j.apnum.2024.10.003","url":null,"abstract":"<div><div>Modeling unsaturated flow through soils with water uptake by plant root has many applications in agriculture and water resources management. In this study, our aim is to develop efficient numerical techniques for solving the Richards equation with a sink term due to plant root water uptake. The Feddes model is used for water absorption by plant roots, and the van-Genuchten model is employed for capillary pressure. We introduce a numerical approach that combines the localized exponential radial basis function (EXP-RBF) method for space and the second-order backward differentiation formula (BDF2) for temporal discretization. The localized RBF methods eliminate the need for mesh generation and avoid ill-conditioning problems. This approach yields a sparse matrix for the global system, optimizing memory usage and computational time. The proposed implicit EXP-RBF techniques have advantages in terms of accuracy and computational efficiency thanks to the use of BDF2 and the localized RBF method. Modified Picards iteration method for the mixed form of the Richards equation is employed to linearize the system. Various numerical experiments are conducted to validate the proposed numerical model of infiltration with plant root water absorption. The obtained results conclusively demonstrate the effectiveness of the proposed numerical model in accurately predicting soil moisture dynamics under water uptake by plant roots. The proposed numerical techniques can be incorporated in the numerical models where unsaturated flows and water uptake by plant roots are involved such as in hydrology, agriculture, and water management.</div></div>","PeriodicalId":8199,"journal":{"name":"Applied Numerical Mathematics","volume":"208 ","pages":"Pages 79-97"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097230","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