Studies in Applied Mathematics最新文献

Asymptotic Expansions Relating to the Distribution of the Product of Correlated Normal Random Variables 有关相关正态随机变量积分布的渐近展开式

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-11 DOI: 10.1111/sapm.70070

Robert E. Gaunt, Zixin Ye

引用次数: 0

Quasilinear Differential Constraints for Parabolic Systems of Jordan-Block Type Jordan-Block型抛物型系统的拟线性微分约束

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-10 DOI: 10.1111/sapm.70072

Alessandra Rizzo, Pierandrea Vergallo

引用次数: 0

The Dimension of the Disguised Toric Locus of a Reaction Network 反应网络伪装环面轨迹的维数

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-10 DOI: 10.1111/sapm.70071

Gheorghe Craciun, Abhishek Deshpande, Jiaxin Jin

{"title":"The Dimension of the Disguised Toric Locus of a Reaction Network","authors":"Gheorghe Craciun, Abhishek Deshpande, Jiaxin Jin","doi":"10.1111/sapm.70071","DOIUrl":"https://doi.org/10.1111/sapm.70071","url":null,"abstract":"<div>\u0000 \u0000 Mathematical models of reaction networks are ubiquitous in applications, especially in chemistry, biochemistry, chemical engineering, ecology, and population dynamics. Under the standard assumption of mass-action kinetics, reaction networks give rise to general dynamical systems with polynomial right-hand side. These depend on many parameters that are difficult to estimate and can give rise to complex dynamics, including multistability, oscillations, and chaos. On the other hand, a special class of reaction systems called complex-balanced systems are known to exhibit remarkably stable dynamics; in particular, they have unique positive fixed points and no oscillations or chaotic dynamics. One difficulty, when trying to take advantage of the remarkable properties of complex-balanced systems, is that the set of parameters where a network satisfies complex balance may have positive codimension and therefore zero measure. To remedy this we are studying disguised complex balanced systems (also known as disguised toric systems), which may fail to be complex balanced with respect to an original reaction network <math>\u0000 <semantics>\u0000 <mi>G</mi>\u0000 <annotation>$G$</annotation>\u0000 </semantics></math>, but are actually complex balanced with respect to some other network <math>\u0000 <semantics>\u0000 <msup>\u0000 <mi>G</mi>\u0000 <mo>′</mo>\u0000 </msup>\u0000 <annotation>$G^{prime }$</annotation>\u0000 </semantics></math>, and therefore enjoy all the stability properties of complex-balanced systems. This notion is especially useful when the set of parameter values for which the network <math>\u0000 <semantics>\u0000 <mi>G</mi>\u0000 <annotation>$G$</annotation>\u0000 </semantics></math> gives rise to disguised toric systems (i.e., the disguised toric locus of <math>\u0000 <semantics>\u0000 <mi>G</mi>\u0000 <annotation>$G$</annotation>\u0000 </semantics></math>) has codimension zero. Our primary focus is to compute the exact dimension (and therefore the codimension) of this locus. We illustrate the use of our results by applying them to Thomas-type and circadian clock models.</div>","PeriodicalId":51174,"journal":{"name":"Studies in Applied Mathematics","volume":"154 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144244566","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

Improved Gevrey-1 Estimates of Formal Series Expansions of Center Manifolds 中心流形形式级数展开的改进Gevrey-1估计

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-04 DOI: 10.1111/sapm.70063

Kristian Uldall Kristiansen

{"title":"Improved Gevrey-1 Estimates of Formal Series Expansions of Center Manifolds","authors":"Kristian Uldall Kristiansen","doi":"10.1111/sapm.70063","DOIUrl":"https://doi.org/10.1111/sapm.70063","url":null,"abstract":"In this paper, we show that the coefficients <math>\u0000 <semantics>\u0000 <msub>\u0000 <mi>ϕ</mi>\u0000 <mi>n</mi>\u0000 </msub>\u0000 <annotation>$phi _n$</annotation>\u0000 </semantics></math> of the formal series expansions <math>\u0000 <semantics>\u0000 <mrow>\u0000 <msubsup>\u0000 <mo>∑</mo>\u0000 <mrow>\u0000 <mi>n</mi>\u0000 <mo>=</mo>\u0000 <mn>1</mn>\u0000 </mrow>\u0000 <mi>∞</mi>\u0000 </msubsup>\u0000 <msub>\u0000 <mi>ϕ</mi>\u0000 <mi>n</mi>\u0000 </msub>\u0000 <msup>\u0000 <mi>x</mi>\u0000 <mi>n</mi>\u0000 </msup>\u0000 <mo>∈</mo>\u0000 <mi>x</mi>\u0000 <mi>C</mi>\u0000 <mrow>\u0000 <mo>[</mo>\u0000 <mrow>\u0000 <mo>[</mo>\u0000 <mi>x</mi>\u0000 <mo>]</mo>\u0000 </mrow>\u0000 <mo>]</mo>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation>$sum _{n=1}^infty phi _n x^nin xmathbb {C}[[x]]$</annotation>\u0000 </semantics></math> of center manifolds of planar analytic saddle-nodes grow like <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Γ</mi>\u0000 <mo>(</mo>\u0000 <mi>n</mi>\u0000 <mo>+</mo>\u0000 <mi>a</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$Gamma (n+a)$</annotation>\u0000 </semantics></math> (after rescaling <math>\u0000 <semantics>\u0000 <mi>x</mi>\u0000 <annotation>$x$</annotation>\u0000 </semantics></math>) as <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>n</mi>\u0000 <mo>→</mo>\u0000 <mi>∞</mi>\u0000 </mrow>\u0000 <annotation>$nrightarrow infty$</annotation>\u0000 </semantics></math>. Here, the quantity <math>\u0000 <semantics>\u0000 <mi>a</mi>\u0000 <annotation>$a$</annotation>\u0000 </semantics></math> is the formal analytic invariant associated with the saddle-node (following the work of Martinet and Ramis). This growth property of <math>\u0000 <semantics>\u0000 <msub>\u0000 <mi>ϕ</mi>\u0000 <mi>n</mi>\u0000 </msub>\u0000 <annotation>$phi _n$</annotation>\u0000 </semantics></math>, which ","PeriodicalId":51174,"journal":{"name":"Studies in Applied Mathematics","volume":"154 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/sapm.70063","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144206338","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

Using Multidelay Discrete Delay Differential Equations to Accurately Simulate Models With Distributed Delays 用多延迟离散延迟微分方程精确模拟具有分布延迟的模型

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-04 DOI: 10.1111/sapm.70069

Tyler Cassidy

{"title":"Using Multidelay Discrete Delay Differential Equations to Accurately Simulate Models With Distributed Delays","authors":"Tyler Cassidy","doi":"10.1111/sapm.70069","DOIUrl":"https://doi.org/10.1111/sapm.70069","url":null,"abstract":"Delayed processes are ubiquitous throughout biology. These delays may arise through maturation processes or as the result of complex multistep networks, and mathematical models with distributed delays are increasingly used to capture the heterogeneity present in these delayed processes. Typically, these distributed delay differential equations are simulated by discretizing the distributed delay and using existing tools for the resulting multidelay delay differential equations or by using an equivalent representation under additional assumptions on the delayed process. Here, we use the existing framework of functional continuous Runge–Kutta methods to confirm the convergence of this common approach. Our analysis formalizes the intuition that the least accurate numerical method dominates the error. We give a number of examples to illustrate the predicted convergence, derive a new class of equivalences between distributed delay and discrete delay differential equations, and give conditions for the existence of breaking points in the distributed delay differential equation. Finally, our work shows how recently reported multidelay complexity collapse arises naturally from the convergence of equations with multiple discrete delays to equations with distributed delays, offering insight into the dynamics of the Mackey–Glass equation.","PeriodicalId":51174,"journal":{"name":"Studies in Applied Mathematics","volume":"154 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/sapm.70069","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144206340","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 of Predator–Prey Systems With Antipredation Strategy in Open Advective Environments 开放平流环境中具有反捕食策略的捕食-食饵系统的全局动力学

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-04 DOI: 10.1111/sapm.70068

Zhongyuan Sun, Weihua Jiang

{"title":"Global Dynamics of Predator–Prey Systems With Antipredation Strategy in Open Advective Environments","authors":"Zhongyuan Sun, Weihua Jiang","doi":"10.1111/sapm.70068","DOIUrl":"https://doi.org/10.1111/sapm.70068","url":null,"abstract":"<div>\u0000 \u0000 We analyze reaction–diffusion–advection systems with Danckwerts boundary conditions describing the interactions of prey and specialist/generalist predators in open advective environments, in which the cost and benefit of antipredation responses are considered. The existence and stability of semitrivial steady states and positive ones are established via the monotonicity of principal eigenvalues with respect to parameters, priori estimates, and other techniques. Specially, for the specialist predator–prey system, the stability of positive steady states near the semitrivial steady state is proved by the bifurcation and spectral analysis, and we apply the global bifurcation theory to obtain a global bifurcation branch which connects to the positive steady state without fear effect. For the generalist predator–prey system, we establish the global stability of a unique positive steady state by constructing a spatial Lyapunov function. Compared with the case of no fear effect, the results show that antipredation strategy mainly influences the coexistence of both species, and the outcomes for specialist and generalist predators are significantly different. Under small advection rates, high antipredation level can prevent the invasion of specialist predators, while lead to the persistence of generalist predators alone.</div>","PeriodicalId":51174,"journal":{"name":"Studies in Applied Mathematics","volume":"154 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144206339","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

Issue Information-TOC 问题Information-TOC

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-04 DOI: 10.1111/sapm.70073

引用次数: 0

N $N$ -Soliton Matrix mKdV Solutions: Some Special Solutions Revisited N$ N$ -孤子矩阵mKdV解：一些特殊解的再探讨

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-06-04 DOI: 10.1111/sapm.70061

Sandra Carillo, Mauro Lo Schiavo, Cornelia Schiebold

{"title":"N\u0000 $N$\u0000 -Soliton Matrix mKdV Solutions: Some Special Solutions Revisited","authors":"Sandra Carillo, Mauro Lo Schiavo, Cornelia Schiebold","doi":"10.1111/sapm.70061","DOIUrl":"https://doi.org/10.1111/sapm.70061","url":null,"abstract":"In this article, a general solution formula is derived for the <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>d</mi>\u0000 <mo>×</mo>\u0000 <mi>d</mi>\u0000 </mrow>\u0000 <annotation>${sf d}times {sf d}$</annotation>\u0000 </semantics></math>-matrix modified Korteweg–de Vries equation. Then, a solution class corresponding to special parameter choices is examined in detail. Roughly, this class can be described as <math>\u0000 <semantics>\u0000 <mi>N</mi>\u0000 <annotation>$N$</annotation>\u0000 </semantics></math>-solitons (in the sense of Goncharenko) with common phase matrix. It turns out that such a solution even takes values in a commutative subalgebra of the <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>d</mi>\u0000 <mo>×</mo>\u0000 <mi>d</mi>\u0000 </mrow>\u0000 <annotation>${sf d}times {sf d}$</annotation>\u0000 </semantics></math>-matrices. We arrive at a rich picture of possibilities for generalized 1-solitons and at visual patterns of <math>\u0000 <semantics>\u0000 <mi>N</mi>\u0000 <annotation>$N$</annotation>\u0000 </semantics></math>-solitons which combine nonlinear with linear features. The impact of the phase matrix is visualized in computer plots.","PeriodicalId":51174,"journal":{"name":"Studies in Applied Mathematics","volume":"154 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/sapm.70061","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144206341","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

Analyticity and Stable Computation of Dirichlet–Neumann Operators for Laplace's Equation Under Quasiperiodic Boundary Conditions in Two and Three Dimensions 二维和三维拟周期边界条件下拉普拉斯方程Dirichlet-Neumann算子的解析性和稳定计算

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-05-28 DOI: 10.1111/sapm.70059

David P. Nicholls, Jon Wilkening, Xinyu Zhao

{"title":"Analyticity and Stable Computation of Dirichlet–Neumann Operators for Laplace's Equation Under Quasiperiodic Boundary Conditions in Two and Three Dimensions","authors":"David P. Nicholls, Jon Wilkening, Xinyu Zhao","doi":"10.1111/sapm.70059","DOIUrl":"https://doi.org/10.1111/sapm.70059","url":null,"abstract":"Dirichlet–Neumann operators (DNOs) are important to the formulation, analysis, and simulation of many crucial models found in engineering and the sciences. For instance, these operators permit moving-boundary problems, such as the classical water wave problem (free-surface ideal fluid flow under the influence of gravity and capillarity), to be restated in terms of interfacial quantities, which not only eliminates the boundary tracking problem, but also reduces the problem's dimension. While these DNOs have been the object of much recent study regarding their numerical simulation and rigorous analysis, they have yet to be examined in the setting of laterally quasiperiodic boundary conditions. The purpose of this contribution is to begin this investigation with a particular focus on the more realistic simulation of two- and three-dimensional free-surface water waves. Here, we not only carefully define the DNO with respect to these boundary conditions for Laplace's equation, but we also show the rigorous analyticity of these operators with respect to sufficiently smooth boundary perturbations. These theoretical developments suggest a novel algorithm for the stable and high-order simulation of the DNO, which we implement and extensively test.","PeriodicalId":51174,"journal":{"name":"Studies in Applied Mathematics","volume":"154 5","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/sapm.70059","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144148446","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

Zero-Mach Limit of the Viscous Compressible Magnetohydrodynamic Flows Inside a Perfectly Conducting Wall for All Time 完全导电壁内粘性可压缩磁流体力学流动的零马赫极限

IF 2.6 2区数学

Studies in Applied Mathematics Pub Date : 2025-05-26 DOI: 10.1111/sapm.70066

Qiangchang Ju, Zilai Li, Jianjun Xu

引用次数: 0