首页 > 最新文献

Applied Mathematics Letters最新文献

英文 中文
Most probable escape paths in perturbed kinetic Langevin systems 摄动朗格万系统中最可能的逃逸路径
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-10-09 DOI: 10.1016/j.aml.2025.109782
Ying Chao , Jinqiao Duan , Pingyuan Wei
We investigate the exit problem from the domain of attraction of a stable state in kinetic Langevin systems with nongradient perturbations. Using Freidlin–Wentzell large deviation theory, we analyze the most probable escape paths and, through a Hamiltonian formulation combined with Melnikov theory, establish conditions under which the optimal escape path persists as a heteroclinic orbit in the perturbed system. Our results demonstrate that, in the presence of nongradient perturbations, the most probable escape path differs from the time-reversed heteroclinic orbit at leading order in the intensity of the autonomous perturbation. These theoretical findings are corroborated by a numerical example.
研究了具有非梯度扰动的动力学朗之万系统稳态吸引域的出口问题。利用Freidlin-Wentzell大偏差理论,分析了最可能的逃逸路径,并结合Melnikov理论建立了最优逃逸路径在扰动系统中以异斜轨道存在的条件。我们的结果表明,在非梯度扰动存在的情况下,最可能的逃逸路径在自主扰动的强度上不同于时间反转的异斜轨道。这些理论结果得到了数值算例的证实。
{"title":"Most probable escape paths in perturbed kinetic Langevin systems","authors":"Ying Chao ,&nbsp;Jinqiao Duan ,&nbsp;Pingyuan Wei","doi":"10.1016/j.aml.2025.109782","DOIUrl":"10.1016/j.aml.2025.109782","url":null,"abstract":"<div><div>We investigate the exit problem from the domain of attraction of a stable state in kinetic Langevin systems with nongradient perturbations. Using Freidlin–Wentzell large deviation theory, we analyze the most probable escape paths and, through a Hamiltonian formulation combined with Melnikov theory, establish conditions under which the optimal escape path persists as a heteroclinic orbit in the perturbed system. Our results demonstrate that, in the presence of nongradient perturbations, the most probable escape path differs from the time-reversed heteroclinic orbit at leading order in the intensity of the autonomous perturbation. These theoretical findings are corroborated by a numerical example.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109782"},"PeriodicalIF":2.8,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268035","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
Spatiotemporal patterns driven by the nonlocal advection and delay 非局域平流和延迟驱动的时空格局
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-10-08 DOI: 10.1016/j.aml.2025.109783
Yuanyuan Xu, Shuyang Xue
In this paper, we investigate the spatiotemporal dynamics in the nonlocal advection–diffusion equation with delay. The nonlocal advection is characterized by the top-hat kernel and time delay measures the delay phenomenon in the reaction term. The joint effect of the nonlocal advection and delay on the stability of the steady state and spatiotemporal dynamics is investigated. The conditions for the occurrence of Turing bifurcation and Turing–Hopf bifurcation are determined. Our results show that the large perception range can stabilize the steady state, but a small perception range is more likely to make the system unstable, and negative feedback of delay is more easy to make system produce complex patterns. It has also been shown that spatially inhomogeneous oscillatory patterns are triggered by the joint interaction of nonlocal advection and delay, which can not occur only for one factor.
本文研究了具有时滞的非局部平流扩散方程的时空动力学问题。非局部平流以顶帽核为特征,时间延迟度量反应项的延迟现象。研究了非局部平流和延迟对稳态稳定性和时空动力学的共同影响。确定了图灵分岔和图灵-霍普夫分岔发生的条件。我们的研究结果表明,较大的感知范围可以稳定系统的稳态,而较小的感知范围更容易使系统不稳定,并且延迟的负反馈更容易使系统产生复杂的模式。研究还表明,空间非均匀振荡模式是由非局部平流和延迟的共同作用引发的,而不是单一因素引起的。
{"title":"Spatiotemporal patterns driven by the nonlocal advection and delay","authors":"Yuanyuan Xu,&nbsp;Shuyang Xue","doi":"10.1016/j.aml.2025.109783","DOIUrl":"10.1016/j.aml.2025.109783","url":null,"abstract":"<div><div>In this paper, we investigate the spatiotemporal dynamics in the nonlocal advection–diffusion equation with delay. The nonlocal advection is characterized by the top-hat kernel and time delay measures the delay phenomenon in the reaction term. The joint effect of the nonlocal advection and delay on the stability of the steady state and spatiotemporal dynamics is investigated. The conditions for the occurrence of Turing bifurcation and Turing–Hopf bifurcation are determined. Our results show that the large perception range can stabilize the steady state, but a small perception range is more likely to make the system unstable, and negative feedback of delay is more easy to make system produce complex patterns. It has also been shown that spatially inhomogeneous oscillatory patterns are triggered by the joint interaction of nonlocal advection and delay, which can not occur only for one factor.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109783"},"PeriodicalIF":2.8,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267359","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
Numerical simulation of heat transfer and flow characteristics of Walter’s-B fluid over an inclined plate in a semi-infinite magnetic field 半无限磁场下斜板上Walter 's-B流体传热及流动特性的数值模拟
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-10-05 DOI: 10.1016/j.aml.2025.109781
Lin Liu , Baoting Su , Hongqing Song , Libo Feng
As a mathematical tool for addressing problems in unbounded domains, the absorbing boundary conditions derived by artificial boundary method are widely used in various scientific fields. This study mainly investigates the hydrodynamic behavior of Walter’s-B fluid over an inclined plate. Considering the effects of chemical reactions as well as the heat absorption/generation, the governing model is derived. By employing the z-transform, the governing Eqs. defined in an unbounded domain are transformed into a computationally tractable finite domain, for which the finite difference method is applied. Numerical simulations are conducted to analyze the influence of various dimensionless parameters. Finally, a quantitative physical analysis is performed to evaluate the impact of these parameters on the concentration profile, temperature distribution, and velocity field.
人工边界法导出的吸收边界条件作为解决无界领域问题的数学工具,广泛应用于各个科学领域。本文主要研究了斜板上Walter 's-B流体的水动力行为。考虑化学反应和热吸收/产热的影响,推导了控制模型。通过使用z变换,控制方程。将定义在无界域中的问题转化为计算可处理的有限域,并应用有限差分法对其进行求解。通过数值模拟分析了各种无量纲参数的影响。最后,进行了定量的物理分析,以评估这些参数对浓度分布、温度分布和速度场的影响。
{"title":"Numerical simulation of heat transfer and flow characteristics of Walter’s-B fluid over an inclined plate in a semi-infinite magnetic field","authors":"Lin Liu ,&nbsp;Baoting Su ,&nbsp;Hongqing Song ,&nbsp;Libo Feng","doi":"10.1016/j.aml.2025.109781","DOIUrl":"10.1016/j.aml.2025.109781","url":null,"abstract":"<div><div>As a mathematical tool for addressing problems in unbounded domains, the absorbing boundary conditions derived by artificial boundary method are widely used in various scientific fields. This study mainly investigates the hydrodynamic behavior of Walter’s-B fluid over an inclined plate. Considering the effects of chemical reactions as well as the heat absorption/generation, the governing model is derived. By employing the <span><math><mi>z</mi></math></span>-transform, the governing Eqs. defined in an unbounded domain are transformed into a computationally tractable finite domain, for which the finite difference method is applied. Numerical simulations are conducted to analyze the influence of various dimensionless parameters. Finally, a quantitative physical analysis is performed to evaluate the impact of these parameters on the concentration profile, temperature distribution, and velocity field.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109781"},"PeriodicalIF":2.8,"publicationDate":"2025-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145320418","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
Energy-stable port-Hamiltonian systems 能量稳定的港口-哈密顿系统
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-10-04 DOI: 10.1016/j.aml.2025.109784
Patrick Buchfink , Silke Glas , Hans Zwart
We combine energy-stable and port-Hamiltonian (pH) systems to obtain energy-stable port-Hamiltonian (es-pH) systems. The idea is to extend the known energy-stable systems with an input–output port, which results in a pH formulation. One advantage of the new es-pH formulation is that it naturally preserves its es-pH structure throughout discretization (in space and time) and model reduction.
我们结合能量稳定和端口-哈密顿(pH)系统得到能量稳定的端口-哈密顿(es-pH)系统。这个想法是用一个输入输出端口扩展已知的能量稳定系统,从而得到一个pH公式。新的es-pH公式的一个优点是它在整个离散化(在空间和时间上)和模型简化过程中自然地保留了es-pH结构。
{"title":"Energy-stable port-Hamiltonian systems","authors":"Patrick Buchfink ,&nbsp;Silke Glas ,&nbsp;Hans Zwart","doi":"10.1016/j.aml.2025.109784","DOIUrl":"10.1016/j.aml.2025.109784","url":null,"abstract":"<div><div>We combine energy-stable and port-Hamiltonian (<span>pH</span>) systems to obtain <em>energy-stable port-Hamiltonian (<span>es-pH</span>) systems</em>. The idea is to extend the known energy-stable systems with an input–output port, which results in a <span>pH</span> formulation. One advantage of the new <span>es-pH</span> formulation is that it naturally preserves its <span>es-pH</span> structure throughout discretization (in space and time) and model reduction.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109784"},"PeriodicalIF":2.8,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267360","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
Tipping time in a stochastic phosphorus dynamics model 随机磷动力学模型的倾倒时间
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-10-03 DOI: 10.1016/j.aml.2025.109779
Anji Yang , Tingting Yu , Tonghua Zhang
Abrupt transitions between oligotrophic and eutrophic states have been observed in shallow lakes, yet the mechanisms underlying these transitions remain poorly understood. To investigate the evolution of a lake from an oligotrophic state to a eutrophic state and to determine the tipping time associated with this transition, we propose a probabilistic framework that characterizes the maximum likelihood transition path between the two states. We derive analytical expressions and numerical methods to calculate the maximum likelihood trajectories. Subsequently, we utilize the maximal likelihood trajectory to ascertain tipping times for the most probable transitions from oligotrophic to eutrophic states. Our findings indicate that increasing environmental stochasticity is associated with reduced tipping times, thereby promoting the eutrophication of lakes. Furthermore, tipping time serves as an effective metric for assessing the stability of the oligotrophic state; we posit that a shorter tipping time correlates with greater instability within the oligotrophic state.
在浅湖中观察到贫营养和富营养状态之间的突变,但这些转变背后的机制仍然知之甚少。为了研究湖泊从贫营养状态到富营养状态的演变,并确定与此过渡相关的临界点时间,我们提出了一个概率框架,该框架表征了两种状态之间的最大似然过渡路径。我们推导了计算最大似然轨迹的解析表达式和数值方法。随后,我们利用最大似然轨迹来确定从贫营养状态到富营养状态最可能转变的引爆时间。我们的研究结果表明,环境随机性的增加与倾倒时间的减少有关,从而促进湖泊的富营养化。此外,倾倒时间可以作为评估少营养状态稳定性的有效指标;我们假设,在少营养状态下,更短的引爆时间与更大的不稳定性相关。
{"title":"Tipping time in a stochastic phosphorus dynamics model","authors":"Anji Yang ,&nbsp;Tingting Yu ,&nbsp;Tonghua Zhang","doi":"10.1016/j.aml.2025.109779","DOIUrl":"10.1016/j.aml.2025.109779","url":null,"abstract":"<div><div>Abrupt transitions between oligotrophic and eutrophic states have been observed in shallow lakes, yet the mechanisms underlying these transitions remain poorly understood. To investigate the evolution of a lake from an oligotrophic state to a eutrophic state and to determine the tipping time associated with this transition, we propose a probabilistic framework that characterizes the maximum likelihood transition path between the two states. We derive analytical expressions and numerical methods to calculate the maximum likelihood trajectories. Subsequently, we utilize the maximal likelihood trajectory to ascertain tipping times for the most probable transitions from oligotrophic to eutrophic states. Our findings indicate that increasing environmental stochasticity is associated with reduced tipping times, thereby promoting the eutrophication of lakes. Furthermore, tipping time serves as an effective metric for assessing the stability of the oligotrophic state; we posit that a shorter tipping time correlates with greater instability within the oligotrophic state.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109779"},"PeriodicalIF":2.8,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145229518","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
Multiple-direction conjugate gradient method via Gram–Schmidt A-orthogonalization with applications to nonlinear system identification Gram-Schmidt a -正交多方向共轭梯度法在非线性系统辨识中的应用
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-10-01 DOI: 10.1016/j.aml.2025.109780
Yawen Mao , Chen Xu , Jiahe Yu , Feng Ding
This letter proposes a multiple-direction conjugate gradient (MD-CG) iterative algorithm accelerated by Gram–Schmidt A-orthogonalization for parameter estimation in nonlinear NARMAX systems. Unlike the traditional CG algorithm that updates along a single conjugate direction per iteration, the MD-CG algorithm generates p mutually A-orthogonal search directions through a modified Gram–Schmidt process, and the convergence speed increases with increasing p. Theoretical analysis shows that the convergence speed of the MD-CG algorithm can reach pth power acceleration of the CG algorithm under ideal conditions, and is especially suitable for large-scale systems. A simulation example is provided to verify the superiority of the proposed algorithm in terms of parameter estimation speed and accuracy.
本文提出了一种由Gram-Schmidt a -正交化加速的多方向共轭梯度(MD-CG)迭代算法,用于非线性NARMAX系统的参数估计。与传统CG算法每次迭代沿单一共轭方向更新不同,MD-CG算法通过改进的Gram-Schmidt过程生成p个相互a正交的搜索方向,并且收敛速度随着p的增加而增加。理论分析表明,MD-CG算法的收敛速度在理想条件下可以达到CG算法的p次幂加速度,特别适用于大型系统。仿真实例验证了该算法在参数估计速度和精度方面的优越性。
{"title":"Multiple-direction conjugate gradient method via Gram–Schmidt A-orthogonalization with applications to nonlinear system identification","authors":"Yawen Mao ,&nbsp;Chen Xu ,&nbsp;Jiahe Yu ,&nbsp;Feng Ding","doi":"10.1016/j.aml.2025.109780","DOIUrl":"10.1016/j.aml.2025.109780","url":null,"abstract":"<div><div>This letter proposes a multiple-direction conjugate gradient (MD-CG) iterative algorithm accelerated by Gram–Schmidt <span><math><mi>A</mi></math></span>-orthogonalization for parameter estimation in nonlinear NARMAX systems. Unlike the traditional CG algorithm that updates along a single conjugate direction per iteration, the MD-CG algorithm generates <span><math><mi>p</mi></math></span> mutually <span><math><mi>A</mi></math></span>-orthogonal search directions through a modified Gram–Schmidt process, and the convergence speed increases with increasing <span><math><mi>p</mi></math></span>. Theoretical analysis shows that the convergence speed of the MD-CG algorithm can reach <span><math><mi>p</mi></math></span>th power acceleration of the CG algorithm under ideal conditions, and is especially suitable for large-scale systems. A simulation example is provided to verify the superiority of the proposed algorithm in terms of parameter estimation speed and accuracy.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109780"},"PeriodicalIF":2.8,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268033","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
The stability of Runge–Kutta spectral volume methods for 1-D linear hyperbolic equations with constant coefficients 一维常系数线性双曲型方程龙格-库塔谱体积法的稳定性
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-09-30 DOI: 10.1016/j.aml.2025.109776
Di Lei, Huiyan Li, Jing Niu
This paper focuses on proving the stability of the Runge–Kutta spectral volume (RKSV) scheme for solving one-dimensional equations, with a specific analysis of the Radau spectral volume (RRSV) and Gauss–Legendre spectral volume (LSV) schemes. By comparing the similarities and discrepancies between the Runge–Kutta spectral volume (RKSV) and Runge–Kutta discontinuous Galerkin (RKDG) schemes, we transform the stability analysis of the RKSV scheme into that of the RKDG scheme-an approach that already possesses a well-established theoretical analysis basis. Our key findings reveal two critical results: first, the Runge–Kutta Radau spectral volume (RKRRSV) scheme is entirely equivalent to the RKDG scheme; second, under the framework of a newly defined norm, the Runge–Kutta Gauss–Legendre spectral volume (RKLSV) scheme yields stability results identical to those of the RKDG scheme. Furthermore, numerical experiments are conducted to validate both the stability and optimal convergence properties of the RKSV scheme, providing empirical support for its theoretical conclusions.
本文重点证明了龙格-库塔光谱体积(RKSV)格式求解一维方程的稳定性,具体分析了Radau光谱体积(RRSV)和Gauss-Legendre光谱体积(LSV)格式。通过比较龙格-库塔谱体积(RKSV)和龙格-库塔不连续Galerkin (RKDG)格式的异同点,将RKSV格式的稳定性分析转化为RKDG格式的稳定性分析,这种方法已经有了完善的理论分析基础。我们的主要发现揭示了两个关键结果:第一,Runge-Kutta Radau光谱体积(RKRRSV)格式与RKDG格式完全等效;其次,在新定义范数的框架下,Runge-Kutta Gauss-Legendre谱体积(RKLSV)格式得到与RKDG格式相同的稳定性结果。通过数值实验验证了RKSV格式的稳定性和最优收敛性,为其理论结论提供了经验支持。
{"title":"The stability of Runge–Kutta spectral volume methods for 1-D linear hyperbolic equations with constant coefficients","authors":"Di Lei,&nbsp;Huiyan Li,&nbsp;Jing Niu","doi":"10.1016/j.aml.2025.109776","DOIUrl":"10.1016/j.aml.2025.109776","url":null,"abstract":"<div><div>This paper focuses on proving the stability of the Runge–Kutta spectral volume (RKSV) scheme for solving one-dimensional equations, with a specific analysis of the Radau spectral volume (RRSV) and Gauss–Legendre spectral volume (LSV) schemes. By comparing the similarities and discrepancies between the Runge–Kutta spectral volume (RKSV) and Runge–Kutta discontinuous Galerkin (RKDG) schemes, we transform the stability analysis of the RKSV scheme into that of the RKDG scheme-an approach that already possesses a well-established theoretical analysis basis. Our key findings reveal two critical results: first, the Runge–Kutta Radau spectral volume (RKRRSV) scheme is entirely equivalent to the RKDG scheme; second, under the framework of a newly defined norm, the Runge–Kutta Gauss–Legendre spectral volume (RKLSV) scheme yields stability results identical to those of the RKDG scheme. Furthermore, numerical experiments are conducted to validate both the stability and optimal convergence properties of the RKSV scheme, providing empirical support for its theoretical conclusions.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109776"},"PeriodicalIF":2.8,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220890","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
Compact Darboux transformation and multi-pole magnetic waves within a higher-order Heisenberg ferromagnetic model 高阶海森堡铁磁模型中的紧致达布变换和多极电磁波
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-09-30 DOI: 10.1016/j.aml.2025.109777
Xi-Hu Wu , Run-Fa Zhang
Spin waves, as charge-free collective excitations of electron spins, are fundamental to the development of energy-efficient spintronic devices and wave-based computing. This Letter investigates a higher-order Heisenberg ferromagnetic model characterizing the dynamics of the magnetic vector in isotropic ferromagnetism. We construct a direct N-fold Darboux transformation (DT) and a generalized N-fold DT in the compact determinant forms, which enhance the efficiency of obtaining rogue wave, multiple, multi-pole and mixed solutions for the nonlinear systems within the Heisenberg ferromagnetic hierarchy. Those results also help provide a mathematical framework for exploring complex spin wave interactions in ferromagnetic materials.
自旋波作为电子自旋的无电荷集体激发,是发展高能效自旋电子器件和基于波的计算的基础。本文研究了表征各向同性铁磁中磁矢量动力学的高阶海森堡铁磁模型。构造了紧致行列式形式的直接n次达布变换(DT)和广义n次达布变换(DT),提高了求解Heisenberg铁磁体系非线性系统的异常波解、多解、多极解和混合解的效率。这些结果也有助于为探索铁磁材料中复杂的自旋波相互作用提供一个数学框架。
{"title":"Compact Darboux transformation and multi-pole magnetic waves within a higher-order Heisenberg ferromagnetic model","authors":"Xi-Hu Wu ,&nbsp;Run-Fa Zhang","doi":"10.1016/j.aml.2025.109777","DOIUrl":"10.1016/j.aml.2025.109777","url":null,"abstract":"<div><div>Spin waves, as charge-free collective excitations of electron spins, are fundamental to the development of energy-efficient spintronic devices and wave-based computing. This Letter investigates a higher-order Heisenberg ferromagnetic model characterizing the dynamics of the magnetic vector in isotropic ferromagnetism. We construct a direct <span><math><mi>N</mi></math></span>-fold Darboux transformation (DT) and a generalized <span><math><mi>N</mi></math></span>-fold DT in the compact determinant forms, which enhance the efficiency of obtaining rogue wave, multiple, multi-pole and mixed solutions for the nonlinear systems within the Heisenberg ferromagnetic hierarchy. Those results also help provide a mathematical framework for exploring complex spin wave interactions in ferromagnetic materials.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109777"},"PeriodicalIF":2.8,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220889","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
Multiplicity and asymptotic behavior of solutions for a degenerate Kirchhoff type problem 一类退化Kirchhoff型问题解的多重性和渐近性
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-09-30 DOI: 10.1016/j.aml.2025.109775
Xin Zhang , Lin Li , Jijiang Sun
In this paper, we study the following degenerate Kirchhoff-type problem abΩ|u|2dxΔu=f(x,u),xΩ,u=0,xΩ,where ΩRN(N=1,2,3) is a bounded smooth domain, a,b>0 are constants, and fC(Ω×R,R). Using genus theory, symmetric mountain pass lemma and cut-off technique, we prove the existence of infinitely many solutions for an odd nonlinearity f(x,u). Depending on whether f is superlinear or sublinear at the origin, we show that the corresponding solution sequence either has energies concentrating at the critical level a2/(4b) or converges to zero in the H01 norm.
本文研究以下简并kirchhoff型问题- a−b∫Ω|∇u|2dxΔu=f(x,u),x∈Ω,u=0,x∈∂Ω,其中Ω∧RN(N=1,2,3)是有界光滑域,a,b>;0是常数,f∈C(Ω×R,R)。利用格理论、对称山口引理和截止技术,证明了一类奇非线性函数f(x,u)的无穷多个解的存在性。根据f在原点是超线性还是次线性,我们证明了相应的解序列要么能量集中在临界能级a2/(4b),要么在H01范数收敛到零。
{"title":"Multiplicity and asymptotic behavior of solutions for a degenerate Kirchhoff type problem","authors":"Xin Zhang ,&nbsp;Lin Li ,&nbsp;Jijiang Sun","doi":"10.1016/j.aml.2025.109775","DOIUrl":"10.1016/j.aml.2025.109775","url":null,"abstract":"<div><div>In this paper, we study the following degenerate Kirchhoff-type problem <span><span><span><math><mfenced><mrow><mtable><mtr><mtd></mtd><mtd><mo>−</mo><mfenced><mrow><mi>a</mi><mo>−</mo><mi>b</mi><msub><mrow><mo>∫</mo></mrow><mrow><mi>Ω</mi></mrow></msub><msup><mrow><mrow><mo>|</mo><mo>∇</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mn>2</mn></mrow></msup><mi>d</mi><mi>x</mi></mrow></mfenced><mi>Δ</mi><mi>u</mi><mo>=</mo><mi>f</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>u</mi><mo>)</mo></mrow><mo>,</mo><mspace></mspace><mi>x</mi><mo>∈</mo><mi>Ω</mi><mo>,</mo></mtd></mtr><mtr><mtd></mtd><mtd><mi>u</mi><mo>=</mo><mn>0</mn><mo>,</mo><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mspace></mspace><mi>x</mi><mo>∈</mo><mi>∂</mi><mi>Ω</mi><mo>,</mo></mtd></mtr></mtable></mrow></mfenced></math></span></span></span>where <span><math><mrow><mi>Ω</mi><mo>⊂</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>N</mi></mrow></msup><mrow><mo>(</mo><mi>N</mi><mo>=</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>)</mo></mrow></mrow></math></span> is a bounded smooth domain, <span><math><mrow><mi>a</mi><mo>,</mo><mi>b</mi><mo>&gt;</mo><mn>0</mn></mrow></math></span> are constants, and <span><math><mrow><mi>f</mi><mo>∈</mo><mi>C</mi><mrow><mo>(</mo><mi>Ω</mi><mo>×</mo><mi>R</mi><mo>,</mo><mi>R</mi><mo>)</mo></mrow></mrow></math></span>. Using genus theory, symmetric mountain pass lemma and cut-off technique, we prove the existence of infinitely many solutions for an odd nonlinearity <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>u</mi><mo>)</mo></mrow></mrow></math></span>. Depending on whether <span><math><mi>f</mi></math></span> is superlinear or sublinear at the origin, we show that the corresponding solution sequence either has energies concentrating at the critical level <span><math><mrow><msup><mrow><mi>a</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>/</mo><mrow><mo>(</mo><mn>4</mn><mi>b</mi><mo>)</mo></mrow></mrow></math></span> or converges to zero in the <span><math><msubsup><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow><mrow><mn>1</mn></mrow></msubsup></math></span> norm.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109775"},"PeriodicalIF":2.8,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268034","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
Multiple normalized solutions for non-autonomous Kirchhoff equations with mass-subcritical nonlinearity in R3 具有质量亚临界非线性的非自治Kirchhoff方程的多重归一化解
IF 2.8 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2025-09-30 DOI: 10.1016/j.aml.2025.109778
Rui Wang , Juntao Sun , Sofiane Khoutir , Han-Su Zhang
In this paper, we are concerned with the multiplicity of normalized solutions for a class of Kirchhoff equations with the nonlinearity h(ɛx)|u|p2u in R3, where ɛ>0 and 4p<14/3. We explore the relationship between the number of solutions and the shape of the weight function h.
本文研究了一类在R3中具有非线性的Kirchhoff方程的归一化解的多重性,其中,λ >;0和4≤p<;14/3。我们探讨了解的数目和权函数h的形状之间的关系。
{"title":"Multiple normalized solutions for non-autonomous Kirchhoff equations with mass-subcritical nonlinearity in R3","authors":"Rui Wang ,&nbsp;Juntao Sun ,&nbsp;Sofiane Khoutir ,&nbsp;Han-Su Zhang","doi":"10.1016/j.aml.2025.109778","DOIUrl":"10.1016/j.aml.2025.109778","url":null,"abstract":"<div><div>In this paper, we are concerned with the multiplicity of normalized solutions for a class of Kirchhoff equations with the nonlinearity <span><math><mrow><mi>h</mi><mrow><mo>(</mo><mi>ɛ</mi><mi>x</mi><mo>)</mo></mrow><msup><mrow><mrow><mo>|</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mi>p</mi><mo>−</mo><mn>2</mn></mrow></msup><mi>u</mi></mrow></math></span> in <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span>, where <span><math><mrow><mi>ɛ</mi><mo>&gt;</mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mn>4</mn><mo>≤</mo><mi>p</mi><mo>&lt;</mo><mn>14</mn><mo>/</mo><mn>3</mn></mrow></math></span>. We explore the relationship between the number of solutions and the shape of the weight function <span><math><mi>h</mi></math></span>.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"173 ","pages":"Article 109778"},"PeriodicalIF":2.8,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220885","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
期刊
Applied Mathematics Letters
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1