Computers & Mathematics with Applications最新文献_第8页

Artificial Neural Network-Based Parameter Estimation in Lattice Boltzmann Simulations of MHD Nanofluid Natural Convection with Oscillating Wall Temperature 基于人工神经网络的MHD纳米流体自然对流振荡壁温晶格Boltzmann模拟参数估计

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-03-01 Epub Date: 2025-12-27 DOI: 10.1016/j.camwa.2025.12.020

C Venkata Lakshmi , Anuradha Aravapalli , K Venkatadri , Hakan F. Öztop

{"title":"Artificial Neural Network-Based Parameter Estimation in Lattice Boltzmann Simulations of MHD Nanofluid Natural Convection with Oscillating Wall Temperature","authors":"C Venkata Lakshmi , Anuradha Aravapalli , K Venkatadri , Hakan F. Öztop","doi":"10.1016/j.camwa.2025.12.020","DOIUrl":"10.1016/j.camwa.2025.12.020","url":null,"abstract":"<div><div>This study investigates magnetohydrodynamic natural convection of nanofluids in a square cavity subjected to sinusoidally varying thermal boundary conditions along the bottom wall. Understanding such flows is important for applications in thermal management, energy systems, and materials processing. The problem is solved using the lattice Boltzmann method coupled with an artificial neural network model to accelerate prediction of heat transfer responses. A comprehensive parametric analysis is performed for Rayleigh numbers up to <span><math><msup><mrow><mn>10</mn></mrow><mn>6</mn></msup></math></span>, Hartmann numbers up to 40, nanoparticle concentrations up to 4%, and a range of thermal wavelength parameters. The results show that the oscillatory thermal boundary significantly modifies flow structures and heat transfer characteristics: for example, at <span><math><mrow><mi>R</mi><mi>a</mi><mo>=</mo><msup><mrow><mn>10</mn></mrow><mn>6</mn></msup></mrow></math></span> and τ=0.5, the average Nusselt number is enhanced by nearly 28% compared with uniform heating, while strong magnetic damping (Ha=40) reduces it by about 35%. The neural network model reproduces LBM results with prediction errors below 2%, offering rapid estimation of Nusselt numbers across the studied parameter space. The novelty of this work lies in combining a high-fidelity lattice Boltzmann solver with data-driven prediction to study magnetically controlled nanofluid convection under oscillatory heating, an area not previously addressed in the literature. These findings provide new insights into the manipulation of convective transport in multiphysics thermal systems.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"205 ","pages":"Pages 40-62"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145842450","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

Strong convergence analysis of time discretization for stochastic nonlinear diffusion-wave equations driven by fractional Brownian motion 分数阶布朗运动驱动随机非线性扩散波方程时间离散化的强收敛性分析

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-03-01 Epub Date: 2026-01-17 DOI: 10.1016/j.camwa.2026.01.011

Xing Liu , Yumeng Yang

引用次数: 0

A novel evolutionary model using the Caputo time-fractional derivative and noise estimator for image denoising and contrast enhancement 一种基于卡普托时间分数阶导数和噪声估计的图像去噪和对比度增强的进化模型

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2026-01-24 DOI: 10.1016/j.camwa.2026.01.006

Anouar Ben-Loghfyry , Abderrahim Charkaoui , Anass Bouchriti , Nour Eddine Alaa

{"title":"A novel evolutionary model using the Caputo time-fractional derivative and noise estimator for image denoising and contrast enhancement","authors":"Anouar Ben-Loghfyry , Abderrahim Charkaoui , Anass Bouchriti , Nour Eddine Alaa","doi":"10.1016/j.camwa.2026.01.006","DOIUrl":"10.1016/j.camwa.2026.01.006","url":null,"abstract":"<div><div>This paper proposes a novel fractional nonlinear parabolic model based on <em>Caputo</em> time-fractional derivative, designed to enhance the classical Perona-Malik model for image denoising and contrast improvement. A regularized diffusion mechanism is incorporated to control the diffusion rate and direction locally. The well-posedness of the model is analyzed, and two main existence results for weak solutions are established. The first, under a bounded reaction term, is proved using Schauder’s fixed-point theorem; the second, involving a nonlinear and weakly regular source term, ensures the existence of a weak SOLA solution via approximation techniques and new technical estimates. Numerical experiments on grayscale and MRI images validate the robustness and efficiency of the proposed model under various noise levels. The results show superior denoising and enhancement performance compared to state-of-the-art methods, preserving natural appearance and minimizing artifacts. This confirms the model’s potential for high-precision image restoration applications.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"204 ","pages":"Pages 305-346"},"PeriodicalIF":2.5,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037729","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 parameter-free approach for 3D staggered Lagrangian hydrodynamics 三维交错拉格朗日流体力学的无参数方法

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2026-01-20 DOI: 10.1016/j.camwa.2026.01.002

Xihua Xu , Xuan Zhou

引用次数: 0

Macroscopic reconstruction of the lattice Boltzmann model for incompressible flows 不可压缩流晶格玻尔兹曼模型的宏观重建

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2025-12-16 DOI: 10.1016/j.camwa.2025.12.001

Jinhua Lu , Nikolaus A. Adams

{"title":"Macroscopic reconstruction of the lattice Boltzmann model for incompressible flows","authors":"Jinhua Lu , Nikolaus A. Adams","doi":"10.1016/j.camwa.2025.12.001","DOIUrl":"10.1016/j.camwa.2025.12.001","url":null,"abstract":"<div><div>The present work proposes a general framework that combines the good numerical stability of the lattice Boltzmann model for incompressible flows (LBM-IF) and the flexibility of finite difference/volume methods in using nonuniform meshes and removing higher-order deviation terms. By adopting the second-order non-equilibrium moment as fundamental variables and neglecting higher-order non-equilibrium moments, to approximately increase entropy in the collision process, the non-equilibrium-moment-based macroscopic equations of LBM-IF are derived. Numerical investigations demonstrate that discretized equations can achieve even better numerical stability than the single-relaxation-time LBM-IF. It is concluded that the good numerical stability of LBM-IF can be roughly interpreted as the entropy increase of the collision step and the diffusion process of the streaming step. However, the discretized non-equilibrium-moments-based macroscopic equations are found to have significant numerical errors at a fixed Reynolds number and very small kinematic viscosities. By combining the non-equilibrium-moments-based and equilibrium-moments-based macroscopic equations, the paper proposes a hybrid model that achieves good numerical stability and accuracy for both small and large kinematic viscosities, even for inviscid flow. The deviation term in the recovered momentum equation of LBM-IF can be easily removed in the hybrid model. Compared with LBM-IF, finite difference/volume solvers based on the hybrid model exhibit better numerical stability and accuracy, as well as superior efficiency in simulations using nonuniform meshes.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"204 ","pages":"Pages 24-51"},"PeriodicalIF":2.5,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145784756","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

An alternating approach for reconstructing the initial value and source term in a time-fractional diffusion-wave equation 一种交替重建时间分数扩散波方程初值和源项的方法

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2026-01-10 DOI: 10.1016/j.camwa.2026.01.004

Yun Zhang , Xiaoli Feng , Xiongbin Yan

引用次数: 0

Hygro-thermo-mechanical-electro coupling inhomogeneous isogeometric analysis of functionally graded piezoelectric structures under hygrothermal environment 湿热环境下功能梯度压电结构的水热机电耦合非均匀等几何分析

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2025-12-22 DOI: 10.1016/j.camwa.2025.12.002

Zhong Zhang, Bo Cui, Pengxu Chen, Liming Zhou, Yue Wu

{"title":"Hygro-thermo-mechanical-electro coupling inhomogeneous isogeometric analysis of functionally graded piezoelectric structures under hygrothermal environment","authors":"Zhong Zhang, Bo Cui, Pengxu Chen, Liming Zhou, Yue Wu","doi":"10.1016/j.camwa.2025.12.002","DOIUrl":"10.1016/j.camwa.2025.12.002","url":null,"abstract":"<div><div>The functionally graded piezoelectric structure (FGPS) is one of the core structures for the design and development of new intelligent components, and has excellent piezoelectric effect and gradient distribution characteristics. Since FGPS has a complex structure and often operates in complex environments, it is essential to propose an efficient algorithm for solving the multi-physics coupling problem of FGPS. Based on the structural characteristics of FGPS, this study introduces NURBS basis functions, proposes hygro-thermo-mechanical-electro coupling inhomogeneous isogeometric analysis (HTMEI-IGA) combining the constitutive equations and boundary conditions of FGPS, and derives the control equations and motion equations of HTMEI-IGA. The free vibration, transient response and harmonic response of FGPS in the hygrothermal field are solved using the subspace iteration method and the Newmark method. The convergence and accuracy of HTMEI-IGA are verified through multiple numerical examples. The influence of exponential factors, moisture and thermal on the FGPS structure is also studied, providing a new means for design and development of FGPS.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"204 ","pages":"Pages 71-96"},"PeriodicalIF":2.5,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145813853","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

Nonconforming finite element method and reduced order algorithm for poroelasticity problem 孔隙弹性问题的非协调有限元法及降阶算法

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2026-01-01 DOI: 10.1016/j.camwa.2025.12.022

Xue Wang , Hongxing Rui , Xiaozhe Hu

引用次数: 0

Unconditionally energy-stable and accurate schemes based on hyperbolic tangent scalar auxiliary variable approach for gradient flows 基于双曲正切标量辅助变量方法的梯度流无条件能量稳定精确格式

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2026-01-14 DOI: 10.1016/j.camwa.2025.12.031

Haihong Zhou , Huan Zhang , Xiaomin Pan

{"title":"Unconditionally energy-stable and accurate schemes based on hyperbolic tangent scalar auxiliary variable approach for gradient flows","authors":"Haihong Zhou , Huan Zhang , Xiaomin Pan","doi":"10.1016/j.camwa.2025.12.031","DOIUrl":"10.1016/j.camwa.2025.12.031","url":null,"abstract":"<div><div>In this paper, we extend the selection of auxiliary variables by proposing a hyperbolic tangent scalar auxiliary variable (tanh-SAV) approach for solving gradient flows. The proposed tanh-SAV schemes introduce an auxiliary variable based on the hyperbolic tangent function, providing a well-defined formulation that enables the construction of decoupled, linear, and efficient numerical schemes. We demonstrate the construction of first-order, second-order, and higher-order unconditionally energy-stable schemes, utilizing either the Crank–Nicolson method or a <em>k</em>-step backward differentiation formula for time discretization. Only one constant-coefficient equation needs to be solved per time step, and we prove that all resulting tanh-SAV schemes are uniquely solvable at each time level. Furthermore, the theoretical analysis demonstrates the discrete energy stability of the proposed numerical schemes and proves the positivity property of the auxiliary variable. For the tanh-SAV/BDF<em>k</em> schemes (<span><math><mrow><mi>k</mi><mo>=</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>,</mo><mn>4</mn></mrow></math></span>) combined with a Fourier pseudo-spectral spatial discretization, we further establish fully discrete optimal-order error estimates. In addition, we provide numerical simulations of one- and two-dimensional Cahn–Hilliard, Allen–Cahn, and phase-field crystal models. The results demonstrate that, consistent with the theoretical analysis, the proposed schemes preserve the positivity of the auxiliary variable, maintain excellent stability, and achieve the desired temporal accuracy.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"204 ","pages":"Pages 263-282"},"PeriodicalIF":2.5,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977942","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

Image restoration strategy stimulated level set model for segmenting images with strongly disturbance information 图像恢复策略刺激水平集模型对具有强干扰信息的图像进行分割

IF 2.5 2区数学

Computers & Mathematics with Applications Pub Date : 2026-02-15 Epub Date: 2025-12-24 DOI: 10.1016/j.camwa.2025.11.023

Yanjun Ren , Dong Li , Liming Tang

{"title":"Image restoration strategy stimulated level set model for segmenting images with strongly disturbance information","authors":"Yanjun Ren , Dong Li , Liming Tang","doi":"10.1016/j.camwa.2025.11.023","DOIUrl":"10.1016/j.camwa.2025.11.023","url":null,"abstract":"<div><div>In order to solve the problems of pixel misclassification, boundary leakage and unstable segmentation model encountered by the traditional level set method when dealing with images with strong disturbance information, this paper introduces a new energy functional based on a global-like global fitting term and a variational denoising term into variational level set framework, which not only significantly improves the segmentation of severe intensity inhomogeneous images and effectively realizes the denoising and deblurring process of images. Specifically, we utilize fitting term constructed with global and global-like information to reduce the sensitivity of the traditional level set method to intensity inhomogeneity. At the same time, we introduce a bounded Hessian variational restoration term to effectively suppressing the undesirable effects of strong noise, staircase artifacts, and blurring on segmentation. Moreover, a new edge indicator function was designed to enhance the model’s robustness to weak boundaries of the images. Experimental results on classical datasets demonstrate that our model exhibits significant advantages in noise suppression and edge preservation compared to existing state-of-the-art level set methods. The robustness and scalability of the model make it suitable for a wide range of image segmentation scenarios.</div></div>","PeriodicalId":55218,"journal":{"name":"Computers & Mathematics with Applications","volume":"204 ","pages":"Pages 123-139"},"PeriodicalIF":2.5,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145822950","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