{"title":"Noniterative localized exponential time differencing methods for hyperbolic conservation laws","authors":"Cao-Kha Doan, Phuoc-Toan Huynh, Thi-Thao-Phuong Hoang","doi":"10.1007/s10444-025-10240-0","DOIUrl":"10.1007/s10444-025-10240-0","url":null,"abstract":"<div><p>The paper is concerned with efficient time discretization methods based on exponential integrators for scalar hyperbolic conservation laws. The model problem is first discretized in space by the discontinuous Galerkin method, resulting in a system of nonlinear ordinary differential equations. To solve such a system, exponential time differencing of order 2 (ETDRK2) is employed with Jacobian linearization at each time step. The scheme is fully explicit and relies on the computation of matrix exponential vector products. To accelerate such computation, we further construct a noniterative, nonoverlapping domain decomposition algorithm, namely localized ETDRK2, which loosely decouples the system at each time step via suitable interface conditions. Temporal error analysis of the proposed global and localized ETDRK2 schemes is rigorously proved; moreover, the schemes are shown to be conservative under periodic boundary conditions. Numerical results for the Burgers’ equation in one and two dimensions (with moving shocks) are presented to verify the theoretical results and illustrate the performance of the global and localized ETDRK2 methods where large time step sizes can be used without affecting numerical stability.</p></div>","PeriodicalId":50869,"journal":{"name":"Advances in Computational Mathematics","volume":"51 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nonlinear Schrödinger equations of general form and their exact solutions","authors":"Nikolay A. Kudryashov , Andrei D. Polyanin","doi":"10.1016/j.aml.2025.109622","DOIUrl":"10.1016/j.aml.2025.109622","url":null,"abstract":"<div><div>The wide class of nonlinear Schrödinger equation of the general form is studied. These nonlinear partial differential equations, depending on arbitrary functions, are not integrable by the inverse scattering transform but have exact solutions. The approach is proposed that makes it possible to find nonlinear Schrodinger equations of the general form that have exact solutions. This approach is that the solutions of nonlinear Schrödinger equations are expressed in a special way through the solutions of auxiliary nonlinear ordinary differential equations of the second order. In this case, one constraint is imposed on three arbitrary functions that determine the class of nonlinear partial differential equations under consideration. A number of new nonlinear Schrödinger equations are presented, which admit generalized traveling wave solutions expressed in terms of elementary and elliptic functions. The described new approach and exact solutions can be used as test problems intended to assess the accuracy of numerical and approximate analytical methods for solving complex nonlinear partial differential equations of mathematical physics.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"170 ","pages":"Article 109622"},"PeriodicalIF":2.9,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147120","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":"Symmetric and exterior squares of hook representations","authors":"Szabolcs Mészáros , János Wolosz","doi":"10.1016/j.jpaa.2025.108003","DOIUrl":"10.1016/j.jpaa.2025.108003","url":null,"abstract":"<div><div>We determine the multiplicities of irreducible summands in the symmetric and the exterior squares of hook representations of symmetric groups over a field of characteristic zero.</div></div>","PeriodicalId":54770,"journal":{"name":"Journal of Pure and Applied Algebra","volume":"229 8","pages":"Article 108003"},"PeriodicalIF":0.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144167249","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":"Characterization of the OU matrix of a braid diagram","authors":"Ayaka Shimizu , Yoshiro Yaguchi","doi":"10.1016/j.topol.2025.109440","DOIUrl":"10.1016/j.topol.2025.109440","url":null,"abstract":"<div><div>The OU matrix of a braid diagram is a square matrix that represents the number of over/under crossings of each pair of strands. In this paper, the OU matrix of a pure braid diagram is characterized for up to 5 strands. As an application, the crossing matrix of a positive pure braid is also characterized for up to 5 strands. Moreover, a standard form of the OU matrix is given and characterized for general braids of up to 5 strands.</div></div>","PeriodicalId":51201,"journal":{"name":"Topology and its Applications","volume":"373 ","pages":"Article 109440"},"PeriodicalIF":0.6,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Some observations regarding the stationary Buckley–Leverett equation","authors":"G.M. Coclite , K.H. Karlsen , N.H. Risebro","doi":"10.1016/j.aml.2025.109621","DOIUrl":"10.1016/j.aml.2025.109621","url":null,"abstract":"<div><div>The basic hyperbolic–elliptic black-oil model describes oil–water displacement in a porous medium. Given its mathematical complexity, there is a need for particular simple solutions for validation of numerical methods. We present a class of stationary solutions, which are easy to compute, and in many cases are given by explicit formulae. These solutions are constructed by a nonlinear coupling of two linear equations, an elliptic pressure equation and a hyperbolic saturation equation.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"170 ","pages":"Article 109621"},"PeriodicalIF":2.9,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170614","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":"Weak-strong uniqueness for a specific class of cross-diffusion models with volume filling","authors":"Ling Liu","doi":"10.1016/j.jmaa.2025.129727","DOIUrl":"10.1016/j.jmaa.2025.129727","url":null,"abstract":"<div><div>The weak-strong uniqueness for solutions to a special class of parabolic cross-diffusion systems with volume filling in a bounded domain with no-flux boundary conditions is proved. The diffusion matrix is neither symmetric nor positive definite, but the system possesses a formal gradient-flow or entropy structure. It is shown that any weak solution coincides with a “strong” solution with the same initial data, as long as the “strong” solution exists. The proof is mainly based on the use of the relative entropy modified by small parameters <em>ε</em> and <em>δ</em>, combined with some analytical techniques.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":"551 2","pages":"Article 129727"},"PeriodicalIF":1.2,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of an HIV/AIDS Model with sexual transmission and travel in a patchy environment.","authors":"Juping Zhang, Xueyan Ma, Zhen Jin","doi":"10.1007/s00285-025-02226-9","DOIUrl":"https://doi.org/10.1007/s00285-025-02226-9","url":null,"abstract":"<p><p>In this paper, a multi-patch HIV/AIDS epidemic model with heterosexual transmission is formulated to investigate the impact of travel among patches. It is a system of <math><mrow><mn>6</mn> <msup><mi>n</mi> <mn>2</mn></msup> </mrow> </math> ordinary differential equations describes HIV/AIDS spread in an environment divided into n patches. We derive the basic reproduction number <math><msub><mi>R</mi> <mn>0</mn></msub> </math> . Lower and upper bounds on <math><msub><mi>R</mi> <mn>0</mn></msub> </math> are given. We prove that if <math> <mrow><msub><mi>R</mi> <mn>0</mn></msub> <mo><</mo> <mn>1</mn></mrow> </math> , the disease-free equilibrium is locally asymptotically stable, and if <math> <mrow><msub><mi>R</mi> <mn>0</mn></msub> <mo>></mo> <mn>1</mn></mrow> </math> , there is at least an endemic equilibrium. We apply the model to three patches in which the disease spreads in a patch and dies out in the other two patches when there is no travel between them. We considered three types of connection between three patches: full connection(FC), i.e., <math><mrow><mn>1</mn> <mo>⇔</mo> <mn>2</mn> <mo>⇔</mo> <mn>3</mn> <mo>⇔</mo> <mn>1</mn></mrow> </math> , circular connection(CC), i.e., <math><mrow><mn>1</mn> <mo>↔</mo> <mn>2</mn> <mo>↔</mo> <mn>3</mn> <mo>↔</mo> <mn>1</mn></mrow> </math> and bidirectional connection(BC), i.e., <math><mrow><mn>1</mn> <mo>⇔</mo> <mn>2</mn> <mo>⇔</mo> <mn>3</mn></mrow> </math> . We set different travel and return rates to study the impact of travel on the spread of HIV/AIDS. Numerical simulations confirm the theoretical results and indicate that travel may increase or decrease the spread of HIV/AIDS, i.e. HIV/AIDS may become endemic or die out in three patches when travel occurs, and three types of connection may have different impacts on disease transmission.</p>","PeriodicalId":50148,"journal":{"name":"Journal of Mathematical Biology","volume":"91 1","pages":"2"},"PeriodicalIF":2.2,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144163599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Finite-time stabilization of a class of unbounded parabolic bilinear systems in Hilbert space","authors":"Younes Amaliki, Mohamed Ouzahra","doi":"10.1016/j.jmaa.2025.129720","DOIUrl":"10.1016/j.jmaa.2025.129720","url":null,"abstract":"<div><div>This paper investigates the finite-time stabilization of a class of unbounded bilinear systems in Hilbert spaces. Our methodology involves decomposing the original system into two interconnected subsystems: one that either inherently possesses finite-time stability or lacks it regardless of the feedback control applied, and another for which an appropriate feedback control must be designed to ensure the desired stability properties. By employing the theory of maximal monotone operators and Lyapunov-based methods, we establish sufficient conditions for finite-time stability without assuming the coercivity of the control operator. Applications are presented for heat and biharmonic heat equations, demonstrating the practical relevance of the results. This work extends existing frameworks and provides a broader theoretical foundation for the study of unbounded bilinear systems.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":"551 2","pages":"Article 129720"},"PeriodicalIF":1.2,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A class of time-dependent mixed quasi-variational–hemivariational inequality problems: solvability and applications","authors":"Chang Wang , Yi-bin Xiao , Dong-ling Cai","doi":"10.1016/j.cnsns.2025.108966","DOIUrl":"10.1016/j.cnsns.2025.108966","url":null,"abstract":"<div><div>In this paper, we explore a class of time-dependent mixed quasi-variational-hemivariational inequality problems (TMQVHVI), which are characterized by the dependence of their constraint set on the solutions. We prove a solvability result for TMQVHVI by using a static mixed quasi-variational–hemivariational inequality and a measurable selection lemma. And, moreover, the boundedness and closedness of solution set to TMQVHVI are established. Ultimately, we demonstrate the applicability of the obtained results to a frictional contact model with elastic material and an Oseen model of a generalized incompressible Newtonian fluid, in which the existence of their weak solutions are derived accordingly.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"150 ","pages":"Article 108966"},"PeriodicalIF":3.4,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168098","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":"Bifurcations induced by nonlocal spatial memory versus nonlocal perception.","authors":"Yujia Wang, Yongli Song, Hao Wang","doi":"10.1007/s00285-025-02234-9","DOIUrl":"https://doi.org/10.1007/s00285-025-02234-9","url":null,"abstract":"<p><p>Spatial memory and perception are two key mechanisms driving animal movement's decisions. In this paper, we formulate a reaction-diffusion model incorporating nonlocal spatial memory and nonlocal perception with both kernels characterized by a top-hat function. To understand the impact of species' memory and instantaneous perception on their movement, we investigate how memory-induced diffusion coefficient, perceptual strength, memory delay, and perceptual scale affect the stability and spatiotemporal dynamics of positive steady states. For spatial memory versus perception, we sketch bifurcation curves in the planes of memory delay and perception scale. When memory and perception are weak, the positive constant steady state remains locally asymptotically stable, indicating minimal impact on stability. A larger perception scale preserves stability, whereas a smaller one can induce instability through bifurcations. Specifically, when both the memory-induced diffusion coefficient and perceptual strength are large and share the same sign (or differ in sign), the system undergoes Turing bifurcation to produce spatially nonhomogeneous steady states (or spatially nonhomogeneous periodic solutions via Hopf bifurcation with increased memory delay). When one of these two parameters is large and the other is small, the stability boundary of the positive constant steady state may be governed by Turing bifurcation or a combination of Turing and Hopf bifurcations, potentially leading to higher codimension bifurcations such as Turing-Hopf and Hopf-Hopf bifurcations.</p>","PeriodicalId":50148,"journal":{"name":"Journal of Mathematical Biology","volume":"91 1","pages":"3"},"PeriodicalIF":2.2,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144163603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}