{"title":"Conservation laws of mean field games equations","authors":"Roman Kozlov","doi":"10.1016/j.cnsns.2025.108796","DOIUrl":"10.1016/j.cnsns.2025.108796","url":null,"abstract":"<div><div>Mean field games equations are examined for conservation laws. The system of mean field games equations consists of two partial differential equations: the Hamilton–Jacobi–Bellman equation for the value function and the forward Kolmogorov equation for the probability density. For separable Hamiltonians, this system has a variational structure, i.e., the equations of the system are Euler–Lagrange equations for some Lagrangian functions. Therefore, one can use the Noether theorem to derive the conservation laws using variational and divergence symmetries. In order to find such symmetries, we find symmetries of the PDE system and select variational and divergence ones. The paper considers separable, state-independent Hamiltonians in one-dimensional state space. It examines the most general form of the mean field games system for symmetries and conservation laws and identifies particular cases of the system which lead to additional symmetries and conservation laws.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108796"},"PeriodicalIF":3.4,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143806831","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":"On computation of Darboux polynomials for full Toda lattice","authors":"A.V. Tsiganov","doi":"10.1016/j.cnsns.2025.108815","DOIUrl":"10.1016/j.cnsns.2025.108815","url":null,"abstract":"<div><div>One of the oldest methods for computing invariants of ordinary differential equations is tested using the full Toda lattice model. We show that the standard method of undetermined coefficients and modern symbolic algebra tools together with sufficient computing power allow to compute Darboux invariants without any additional information.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108815"},"PeriodicalIF":3.4,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791655","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":"Abnormal dynamics in cascading models for time-weighted path optimization","authors":"Jianwei Wang, Yiyang Qian, Huize Hu","doi":"10.1016/j.cnsns.2025.108823","DOIUrl":"10.1016/j.cnsns.2025.108823","url":null,"abstract":"<div><div>In real traffic networks, route choice preferences tend to prioritize the shortest travel time over the shortest distance. To address this, we propose a cascading failure model that incorporates time dynamics. By introducing the BPR function, our model quantifies edge transmission time, identifies time-optimal paths, and distributes loads proportionally based on edge time weights. Three parameters are introduced to redefine cascading dynamics and evaluate network robustness.Simulations on both artificial and real-world networks reveal several key findings: First, increasing node weights leads to an uneven load distribution, thereby weakening the network’s robustness. Second, the network exhibits both the “capacity paradox” and the “expansion paradox.” The capacity paradox indicates that increasing the capacity of edges can actually reduce network robustness. In networks with loop structures, enlarging edge capacities redirects traffic to critical edges, creating bottlenecks that amplify cascading failures. Similarly, the expansion paradox shows that increasing maximum capacity can destabilize the network by concentrating loads on key edges, which, if overloaded, can trigger widespread failures. These findings challenge the conventional assumptions that enhancing capacity universally improves robustness. Instead, our results emphasize the importance of balancing topological design and load distribution.For practical networks, strategies such as diversifying travel routes and limiting the load on hub nodes prove to be more effective than simply increasing capacity. This work advances cascading failure modeling by integrating time dynamics and provides actionable insights for improving infrastructure resilience.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108823"},"PeriodicalIF":3.4,"publicationDate":"2025-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791652","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}
Binghao OuYang , Yong Wang , Xingxing Ju , Weichuang Yu
{"title":"Neurodynamic optimization algorithm for split equality problems and application to sparse signal recovery","authors":"Binghao OuYang , Yong Wang , Xingxing Ju , Weichuang Yu","doi":"10.1016/j.cnsns.2025.108822","DOIUrl":"10.1016/j.cnsns.2025.108822","url":null,"abstract":"<div><div>In this paper, we propose a fixed-time neurodynamic optimization algorithm with time-varying coefficients (TFxND) for solving split equality problems. Under bounded linear regularity condition, we prove that the proposed neurodynamic algorithm converges to a solution of the split equality problem in fixed-time, which is independent of the initial states. In addition, the proposed TFxND is applied to solve the sparse signal recovery and sparse image reconstruction. The effectiveness and superiority of the proposed approach are illustrated through numerical experiments, which compare it favorably against other methods. Specifically, compared with the existing state-of-the-art sparse image reconstruction algorithm with fixed-time convergence, our proposed method achieves a 2.94 times speedup while maintaining equivalent reconstruction quality.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108822"},"PeriodicalIF":3.4,"publicationDate":"2025-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791653","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":"An efficient numerical scheme for two-dimensional nonlinear time fractional Schrödinger equation","authors":"Jun Ma , Tao Sun , Hu Chen","doi":"10.1016/j.cnsns.2025.108824","DOIUrl":"10.1016/j.cnsns.2025.108824","url":null,"abstract":"<div><div>In this paper, a linearized fully discrete scheme is proposed to solve the two-dimensional nonlinear time fractional Schrödinger equation with weakly singular solutions, which is constructed by using L1 scheme for Caputo fractional derivative, backward formula for the approximation of nonlinear term and five-point difference scheme in space. We rigorously prove the unconditional stability and pointwise-in-time convergence of the fully discrete scheme, which does not require any restriction on the grid ratio. Numerical results are presented to verify the accuracy of the theoretical analysis.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108824"},"PeriodicalIF":3.4,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783194","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":"LRBF-Based energy-conserving time splitting schemes for the 2D Maxwell equations","authors":"Rong Gao , Jialin Hong , Linghua Kong , Qi Wu","doi":"10.1016/j.cnsns.2025.108813","DOIUrl":"10.1016/j.cnsns.2025.108813","url":null,"abstract":"<div><div>In this paper, several energy-conserving numerical schemes are constructed for solving the two-dimensional Maxwell equations. Initially, the original problem is decomposed into two one-dimensional subproblems using operator splitting techniques. Subsequently, for spatial discretization, we employ the local radial basis function (LRBF) method, while for temporal discretization, three different splitting composition methods are selected, including the Lie-Trotter method, the Strang method, and the three-stage fourth-order splitting method. Through an analysis of the structural characteristics of the spatial differential matrices generated by the LRBF method, the unconditional stability and energy conservation properties of the fully discretized schemes are further proved. Numerical experiments validate the temporal convergence accuracy of the three numerical schemes and the preservation of their relevant properties.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108813"},"PeriodicalIF":3.4,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791654","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 hybrid kernel-free boundary integral method with operator learning for solving parametric partial differential equations in irregular domains","authors":"Shuo Ling , Liwei Tan , Wenjun Ying","doi":"10.1016/j.cnsns.2025.108816","DOIUrl":"10.1016/j.cnsns.2025.108816","url":null,"abstract":"<div><div>The Kernel-Free Boundary Integral (KFBI) method presents an iterative solution to boundary integral equations arising from elliptic partial differential equations (PDEs). This method effectively addresses elliptic PDEs on irregular domains, including the modified Helmholtz, Stokes, and elasticity equations. The rapid evolution of neural networks and deep learning has invigorated the exploration of numerical PDEs. An increasing interest is observed in deep learning approaches that seamlessly integrate mathematical principles for investigating numerical PDEs. We propose a hybrid KFBI method, integrating the foundational principles of the KFBI method with the capabilities of deep learning. This approach, within the framework of boundary integral method, designs a network to approximate the solution operator for the corresponding integral equations by mapping the parameters, inhomogeneous terms and boundary information of PDEs to the boundary density functions, which can be regarded as solution of the integral equations. The models are trained using data generated by the Cartesian grid-based KFBI algorithm, exhibiting robust generalization capabilities. It accurately predicts density functions across diverse boundary conditions and parameters within the same class of equations. Experimental results demonstrate that the trained models can directly infer the boundary density function with satisfactory precision, obviating the need for iterative steps in solving boundary integral equations. Furthermore, applying the inference results of the models as initial values for iterations is also reasonable; this approach can retain the inherent second-order accuracy of the KFBI method while accelerating the traditional KFBI approach by reducing about 50% iterations across a range of problems.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108816"},"PeriodicalIF":3.4,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143821183","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 parameter-robust and decoupled discretization scheme for nonlinear Biot’s model in poroelasticity","authors":"Linshuang He , Xi Li , Minfu Feng","doi":"10.1016/j.cnsns.2025.108798","DOIUrl":"10.1016/j.cnsns.2025.108798","url":null,"abstract":"<div><div>We present a new robust and decoupled scheme for Biot’s model with displacement-dependent nonlinear permeability. The scheme combines a low-order H(div)-conforming element pair <span><math><mrow><msub><mrow><mi>P</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>⊕</mo><msub><mrow><mi>RT</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>−</mo><msub><mrow><mi>P</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span> approximation with a first-order semi-explicit time discretization. Two stabilization terms are incorporated into the modified conforming-like formulation to achieve the scheme’s stability. One term penalizes the nonconformity of the H(div)-conforming component, and the other stabilizes pressure oscillations. The constructed scheme sequentially solves the displacement and pressure, which naturally linearizes the nonlinear terms without additional internal iterations, thus enhancing the computational efficiency. We improve the weak coupling condition and then prove optimal convergence in space and time under this condition. Meanwhile, our scheme provides robust solutions that do not suffer from volumetric locking as the Lamé coefficient tends to infinity and spurious pressure oscillations as the constrained specific storage coefficient and the permeability or time step go to zero. Finally, we verify these theoretical results with several numerical examples of nonlinear displacement–permeability relationships.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108798"},"PeriodicalIF":3.4,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143786227","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":"Accelerated subgradient extragradient methods with increasing self-adaptive step size for variational inequalities","authors":"Zhongbing Xie , Min Li","doi":"10.1016/j.cnsns.2025.108794","DOIUrl":"10.1016/j.cnsns.2025.108794","url":null,"abstract":"<div><div>The main purpose of this paper is to propose and analyze two accelerated subgradient extragradient methods with increasing self-adaptive step size for solving pseudomonotone variational inequality problems in Hilbert spaces. Under some appropriate conditions imposed on the parameters, we combine the inertial subgradient extragradient method with viscosity and Mann-type iterative methods, respectively, and obtain two new algorithms and their corresponding strong convergence theorems. Different from the classical subgradient extragradient method, we introduce new parameters to control the step size, which can effectively improve the convergence process. Finally, the performance of the proposed algorithms is compared with existing related algorithms through several numerical experiments.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108794"},"PeriodicalIF":3.4,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143820255","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}
Zixiang Zhao , Liang Zhang , Shuyi Yang , Ning Zhao , Yongchao Liu
{"title":"Dual-triggered scheme for adaptive neural control of MIMO nonlinear switched systems against sensor and actuator attacks","authors":"Zixiang Zhao , Liang Zhang , Shuyi Yang , Ning Zhao , Yongchao Liu","doi":"10.1016/j.cnsns.2025.108811","DOIUrl":"10.1016/j.cnsns.2025.108811","url":null,"abstract":"<div><div>A dual-triggered adaptive neural control scheme for a class of multiple-input multiple-output (MIMO) switched nonlinear cyber–physical systems under dual-channel deception attack is proposed in this paper. The dual-triggered mechanism for both sensor-to-controller and controller-to-actuator channels within the traditional backstepping framework is designed to effectively reduce the communication and computational burdens, while ensuring the Zeno behavior is avoided. In addition, deception attacks on sensors and actuators are addressed by the designed event-triggered virtual controller and adaptive neural event-triggered controller. The results indicate that the signals of the overall closed-loop system can be bounded by using the developed dual-triggered adaptive neural control scheme. Finally, numerical and practical engineering examples are provided to validate the effectiveness of the scheme.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"147 ","pages":"Article 108811"},"PeriodicalIF":3.4,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143807454","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}