SIAM Journal on Applied Mathematics最新文献_第6页

On Long Waves and Solitons in Particle Lattices with Forces of Infinite Range 论具有无限范围力的粒子晶格中的长波和孤子

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-05-03 DOI: 10.1137/23m1607209

Benjamin Ingimarson, Robert L. Pego

引用次数: 0

Stoichiometry-Dependent Fear Effect in a Food Chain Model 食物链模型中依赖化学计量的恐惧效应

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-05-02 DOI: 10.1137/23m1581613

Tianxu Wang, Hao Wang

引用次数: 0

Multistability for Nematic Liquid Crystals in Cuboids with Degenerate Planar Boundary Conditions 具有退化平面边界条件的立方体中向列液晶的多稳定性

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-04-26 DOI: 10.1137/23m1604606

Baoming Shi, Yucen Han, Apala Majumdar, Lei Zhang

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引用次数: 0

Multiplicity of Endemic Equilibria for a Diffusive SIS Epidemic Model with Mass-Action 具有大规模行动的扩散性 SIS 流行病模型的地方性均衡的多重性

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-04-16 DOI: 10.1137/23m1613888

Keoni Castellano, Rachidi B. Salako

引用次数: 0

Moving Singularities of the Forced Fisher–KPP Equation: An Asymptotic Approach 强迫费希尔-KPP方程的移动奇点：渐近方法

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-04-15 DOI: 10.1137/23m1552905

Markus Kaczvinszki, Stefan Braun

{"title":"Moving Singularities of the Forced Fisher–KPP Equation: An Asymptotic Approach","authors":"Markus Kaczvinszki, Stefan Braun","doi":"10.1137/23m1552905","DOIUrl":"https://doi.org/10.1137/23m1552905","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 710-731, April 2024. <br/> Abstract. The creation of hairpin or lambda vortices, typical for the early stages of the laminar-turbulent transition process in various boundary layer flows, in some sense may be associated with blow-up solutions of the Fisher–Kolmogorov–Petrovsky–Piskunov equation. In contrast to the usual applications of this nonlinear evolution equation of the reaction-diffusion type, the solution quantity in the present context needs to stay neither bounded nor positive. We focus on the solution behavior beyond a finite-time point blow-up event, which consists of two moving singularities (representing the cores of the vortex legs) propagating in opposite directions, and their initial motion is determined with the method of matched asymptotic expansions. After resolving subtleties concerning the transition between logarithmic and algebraic expansion terms regarding asymptotic layers, we find that the internal singularity structure resembles a combination of second- and first-order poles in the form of a singular traveling wave with a time-dependent speed imprinted through the characteristics of the preceding blow-up event.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593502","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}

引用次数: 0

Stability for Inverse Source Problems of the Stochastic Helmholtz Equation with a White Noise 带有白噪声的随机亥姆霍兹方程反源问题的稳定性

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-04-11 DOI: 10.1137/23m1586331

Peijun Li, Ying Liang

引用次数: 0

Constitutive Relations for Granular Flow That Include the Three Flow Regimes of Chialvo et al. 包括 Chialvo 等人的三种流动状态在内的粒状流构成关系

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-04-09 DOI: 10.1137/23m1578097

David G. Schaeffer, Yuhao Hu

引用次数: 0

A Geometric Analysis of the SIRS Model with Secondary Infections 二次感染 SIRS 模型的几何分析

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-04-09 DOI: 10.1137/23m1565632

Panagiotis Kaklamanos, Andrea Pugliese, Mattia Sensi, Sara Sottile

引用次数: 0

Dynamics and Bifurcations in a Nondegenerate Homogeneous Diffusive SIR Rabies Model 非生成同质扩散 SIR 狂犬病模型中的动力学和分岔现象

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-04-09 DOI: 10.1137/23m159055x

Gaoyang She, Fengqi Yi

{"title":"Dynamics and Bifurcations in a Nondegenerate Homogeneous Diffusive SIR Rabies Model","authors":"Gaoyang She, Fengqi Yi","doi":"10.1137/23m159055x","DOIUrl":"https://doi.org/10.1137/23m159055x","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 632-660, April 2024. <br/> Abstract. In this paper, we are interested in the spatiotemporal pattern formations and bifurcations for a nondegenerate reaction-diffusion rabies SIR model which was used to explain the epidemiological patterns observed in Europe. First, by using the iteration methods, we are able to show the global existence and boundedness of in-time solutions of the parabolic system. Second, for the ODEs, we analytically prove the phenomena observed by Anderson et al. [Nature, 289 (1981), pp. 765–771]: if the carrying capacity [math] is smaller than some positive [math], then rabies eventually dies out; if [math] is larger than [math], then the rabies prevails. Moreover, if [math] for some positive [math], then the endemic equilibrium solution is (locally asymptotically) stable, while it is unstable if [math]. In particular, at [math], the loss of the stability of the endemic equilibrium leads to a Hopf bifurcation. Finally, for the PDEs, we derive sufficient conditions on the diffusion rates so that under these conditions, Turing instability of both the endemic equilibrium solution and the Hopf bifurcating spatially homogeneous periodic solutions can occur. Once Turing instability of the solution (equilibrium or periodic solution) occurs, it is observed numerically that the system might have new spatiotemporal patterns.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593808","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}

引用次数: 0

Cover Times of Many Diffusive or Subdiffusive Searchers 许多扩散或亚扩散搜索器的覆盖时间

IF 1.9 4区数学

SIAM Journal on Applied Mathematics Pub Date : 2024-03-29 DOI: 10.1137/23m1576645

Hyunjoong Kim, Sean D. Lawley

{"title":"Cover Times of Many Diffusive or Subdiffusive Searchers","authors":"Hyunjoong Kim, Sean D. Lawley","doi":"10.1137/23m1576645","DOIUrl":"https://doi.org/10.1137/23m1576645","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 602-620, April 2024. <br/> Abstract. Cover times measure the speed of exhaustive searches which require the exploration of an entire spatial region(s). Applications include the immune system hunting pathogens, animals collecting food, robotic demining or cleaning, and computer search algorithms. Mathematically, a cover time is the first time a random searcher(s) comes within a specified “detection radius” of every point in the target region (often the entire spatial domain). Due to their many applications and their fundamental probabilistic importance, cover times have been extensively studied in the physics and probability literatures. This prior work has generally studied cover times of a single searcher with a vanishing detection radius or a large target region. This prior work has further claimed that cover times for multiple searchers can be estimated by a simple rescaling of the cover time of a single searcher. In this paper, we study cover times of many diffusive or subdiffusive searchers and show that prior estimates break down as the number of searchers grows. We prove a rather universal formula for all the moments of such cover times in the many searcher limit that depends only on (i) the searcher’s characteristic (sub)diffusivity and (ii) a certain geodesic distance between the searcher starting location(s) and the farthest point in the target. This formula is otherwise independent of the detection radius, space dimension, target size, and domain size. We illustrate our results in several examples and compare them to detailed stochastic simulations.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593465","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}

引用次数: 0