Mathematics and Computers in Simulation最新文献_第8页

Matrix projective combination synchronization of time-delayed chaotic system and its application in image encryption

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-14 DOI: 10.1016/j.matcom.2025.01.004

Jyotsna Kumari Bharti , K. Murugesan , P. Balasubramaniam

{"title":"Matrix projective combination synchronization of time-delayed chaotic system and its application in image encryption","authors":"Jyotsna Kumari Bharti , K. Murugesan , P. Balasubramaniam","doi":"10.1016/j.matcom.2025.01.004","DOIUrl":"10.1016/j.matcom.2025.01.004","url":null,"abstract":"<div><div>External disturbance, uncertainty and time delay are basic ideas of nonlinear systems that are highly related to the control and synchronization of nonlinear systems. This paper introduces a novel approach for achieving synchronization in non-identical chaotic systems in the presence of model uncertainty, external disturbances and time delay. The proposed method utilizes a matrix projective combination synchronization strategy, demonstrating its efficacy in scenarios both with and without time delay. Notably, the application of this strategy has proven to be valuable and efficient, particularly in the domain of encrypting images. This work proceeds by combining two drive systems and one response system using Lyapunov stability theory and a suitable active control technique. Numerical examples are taken to verify the effectiveness of the proposed method and numerical simulations have been performed to demonstrate that the theoretical results are completely consistent with the graphical results. A significant idea for encryption and decryption algorithms is that the secure transmission of images using affine encryption. In affine encryption algorithm, the key is based on the solution of synchronized chaotic delayed disturbed systems and the birth date and birth time of the sender and receiver. The proposed encryption and decryption algorithms have been applied to plain images. Their effectiveness has been validated through key security metrics. Additionally, a comparative analysis with previously published methods demonstrates the robustness and efficiency of the approach.</div></div>","PeriodicalId":49856,"journal":{"name":"Mathematics and Computers in Simulation","volume":"232 ","pages":"Pages 311-345"},"PeriodicalIF":4.4,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143367927","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

Regularization methods for solving a time-fractional diffusion inverse source problem

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-12 DOI: 10.1016/j.matcom.2025.01.002

Hanghang Wu , Hongqi Yang

引用次数: 0

Inverse scattering transform for the coupled Lakshmanan–Porsezian–Daniel equations with non-zero boundary conditions in optical fiber communications

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-11 DOI: 10.1016/j.matcom.2025.01.008

Peng-Fei Han , Ru-Suo Ye , Yi Zhang

引用次数: 0

State Dependent Riccati for dynamic boundary control to optimize irrigation in Richards’ equation framework

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-11 DOI: 10.1016/j.matcom.2024.12.020

Alessandro Alla , Marco Berardi , Luca Saluzzi

引用次数: 0

A novel fractional-order neutral-type two-delayed neural network: Stability, bifurcation, and numerical solution

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-10 DOI: 10.1016/j.matcom.2025.01.001

Pushpendra Kumar , Tae H. Lee , Vedat Suat Erturk

引用次数: 0

Turing patterns in an intraguild predator–prey model

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-08 DOI: 10.1016/j.matcom.2024.12.022

M.F. Carfora , F. Iovanna , I. Torcicollo

引用次数: 0

An adaptive mesh refinement method considering control errors for pseudospectral discretization

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-08 DOI: 10.1016/j.matcom.2025.01.005

Hesong Li , Zhaoting Li , Hongbo Zhang , Yi Wang

{"title":"An adaptive mesh refinement method considering control errors for pseudospectral discretization","authors":"Hesong Li , Zhaoting Li , Hongbo Zhang , Yi Wang","doi":"10.1016/j.matcom.2025.01.005","DOIUrl":"10.1016/j.matcom.2025.01.005","url":null,"abstract":"<div><div>This paper presents an adaptive mesh refinement method that considers control errors for solving pseudospectral optimal control problems. Firstly, a method for estimating errors in both states and controls is presented. Based on the estimation results, an adaptive mesh refinement method is subsequently devised. This method increases and reduces the number of collocation points in accordance with a theoretical convergence rate that incorporates both state and control errors. Furthermore, in addition to dividing intervals resulting from a large number of collocation points, new intervals are also generated when control errors exceed tolerance. As a result, the mesh density near the point with the largest control error is effectively increased, thereby improving the discretization accuracy. The effectiveness of the method is illustrated through three numerical examples, and its performance is evaluated in comparison to other adaptive mesh refinement methods. The numerical results demonstrate that the proposed method exhibits superior performance in terms of capturing the nonsmooth and discontinuous changes and achieving an accurate solution, while requiring fewer iterations.</div></div>","PeriodicalId":49856,"journal":{"name":"Mathematics and Computers in Simulation","volume":"232 ","pages":"Pages 140-159"},"PeriodicalIF":4.4,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143268913","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

Dynamics of a within-host HIV/SARS-CoV-2 co-infection model with two intracellular delays

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-04 DOI: 10.1016/j.matcom.2024.12.027

Youssra Hajri, Saida Amine

{"title":"Dynamics of a within-host HIV/SARS-CoV-2 co-infection model with two intracellular delays","authors":"Youssra Hajri, Saida Amine","doi":"10.1016/j.matcom.2024.12.027","DOIUrl":"10.1016/j.matcom.2024.12.027","url":null,"abstract":"<div><div>This paper presents a delayed within-host model to investigate the intricate dynamics of HIV/SARS-CoV-2 co-infection. The analysis establishes the existence of unique positive and bounded solutions under specified initial conditions. The healthy, the single HIV infection, the single SARS-CoV-2 infection and the HIV/SARS-CoV-2 co-infection steady states, are computed contingent upon threshold parameters <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>H</mi></mrow></msub></math></span>, <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>C</mi></mrow></msub></math></span>, and <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>H</mi><mi>C</mi></mrow></msub></math></span>. Through rigorous examination of characteristic equations, the local stability of pivotal steady states-namely, the healthy state and the HIV/SARS-CoV-2 co-infection state is elucidated, alongside the identification of Hopf bifurcations using delays as bifurcation parameters. Intriguingly, theoretical analyses reveal that delays exert no discernible influence on the stability of the healthy state, whereas they may destabilize the HIV/SARS-CoV-2 co-infection state under specific conditions. Moreover, employing appropriate Lyapunov functions confirms the global asymptotic stability of all steady states. Complementary numerical simulations are conducted to augment theoretical insights and delineate the nuanced impact of each time delay, albeit without explicit Hopf bifurcation simulations.</div></div>","PeriodicalId":49856,"journal":{"name":"Mathematics and Computers in Simulation","volume":"232 ","pages":"Pages 160-191"},"PeriodicalIF":4.4,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143268914","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

Solving higher-order nonlocal boundary value problems with high precision by the fixed quasi Newton methods

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-04 DOI: 10.1016/j.matcom.2024.12.024

Chein-Shan Liu , Yung-Wei Chen , Jian-Hung Shen , Yen-Shen Chang

{"title":"Solving higher-order nonlocal boundary value problems with high precision by the fixed quasi Newton methods","authors":"Chein-Shan Liu , Yung-Wei Chen , Jian-Hung Shen , Yen-Shen Chang","doi":"10.1016/j.matcom.2024.12.024","DOIUrl":"10.1016/j.matcom.2024.12.024","url":null,"abstract":"<div><div>The paper presents a numerical solution of a higher-order nonlocal and nonlinear boundary value problem (NNBVP); it exhibits triple nonlinearities: nonlinear ordinary differential equation (ODE), nonlinear local boundary values and nonlinear integral boundary conditions (BCs). We consider one nonlocal, two nonlocal and three nonlocal BCs. New variables are incorporated, whose values at right-end present the integral parts in the specified nonlocal BCs. For an extremely precise solution of NNBVP, it is crucial to acquire highly accurate initial values of independent variables by solving target equations very accurately. Because of the implicit form of the target equations, they are solved by a fixed quasi-Newton method (FQNM) without calculating the differentials, which together with the shooting technique would offer nearly exact initial values. Higher-order numerical examples are examined to assure that the proposed methods are efficient to achieve some highly accurate solutions with 14- and 15-digit precisions, whose computational costs are very saving as reflected in the small number of iterations. The computed order of convergence (<em>COC</em>) reveals that the iterative methods converge faster than linear convergence. The novelty lies on the introduction of new variables to present the nonlocal boundary conditions, and develop FQNM to solve the target equations. The difficult part of nonlinear and nonlocal BC is simply transformed to find an ended value of the new variable governed by an ODE. When the constant iteration matrix is properly established, the numerical examples of NNBVP reveal that FQNM is convergent fast and is not sensitive to the initial guesses of unknown initial values.</div></div>","PeriodicalId":49856,"journal":{"name":"Mathematics and Computers in Simulation","volume":"232 ","pages":"Pages 211-226"},"PeriodicalIF":4.4,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143268912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Global dynamics in the lateral oscillation model of pedestrian walking on a vibrating surface

IF 4.4 2区数学

Mathematics and Computers in Simulation Pub Date : 2025-01-04 DOI: 10.1016/j.matcom.2024.12.026

Sengen Hu, Liangqiang Zhou

{"title":"Global dynamics in the lateral oscillation model of pedestrian walking on a vibrating surface","authors":"Sengen Hu, Liangqiang Zhou","doi":"10.1016/j.matcom.2024.12.026","DOIUrl":"10.1016/j.matcom.2024.12.026","url":null,"abstract":"<div><div>This paper studies the lateral oscillations of pedestrian walking on a vibrating ground with a known motion, which can be modeled by a hybrid Rayleigh–van der Pol–Duffing oscillator with quintic nonlinearity and dual parametric excitations. The focus of the work is on the global dynamics of the oscillator, including chaos and subharmonic bifurcations. It reveals that the system can be subdivided into three categories in the undisturbed case: single well, double hump, and triple well. Specifically, the exact solutions for homoclinic, heteroclinic and subharmonic orbits in triple-well case are obtained analytically. The Melnikov method is employed to investigate the chaotic phenomena resulting from different orbits. Compared to a single self-excited oscillator, this hybrid oscillator exhibits higher sensitivity to external excitation and strong nonlinear terms. By adjusting the system parameters, the peak value of the chaos threshold can be controlled to avoid the occurrence of chaos. Based on the subharmonic Melnikov method, the subharmonic bifurcations of the system are examined and the extreme case is discussed. Some nonlinear phenomena are discovered. The system only exhibits chaotic behavior when there is a strong resonance, that is, when there is an integer-order subharmonic bifurcation. Furthermore, we find the pathways to chaos though subharmonic bifurcations encompass two distinct mechanisms: odd and even finite bifurcation sequences. The numerical simulation serves to verify the findings of the preceding analysis, while simultaneously elucidating a number of additional dynamic phenomena, including multi-stable state motion, bursting oscillations, and the coexistence of attractors.</div></div>","PeriodicalId":49856,"journal":{"name":"Mathematics and Computers in Simulation","volume":"232 ","pages":"Pages 427-453"},"PeriodicalIF":4.4,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143269203","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