Pub Date : 2024-11-09DOI: 10.1016/j.aml.2024.109365
Zhongli Liu , Hongjiong Tian
In this paper, we propose high asymptotic order numerical methods for solving highly oscillatory second order ODEs with large initial data, where the total energy of the system becomes unbounded as the oscillation frequency grows. The existing asymptotic-numerical solvers are especially designed for the classical energy bounded oscillatory equations, offering no insight into their performance with energy unbounded case. Based on the asymptotic expansion of the solution in the inverse powers of the oscillatory parameter, we propose an asymptotic numerical integrator to solve this class of highly oscillatory ODEs and discuss the computational efficiency for the case of polynomials. One numerical example is given to show the efficiency and accuracy of our proposed asymptotic-numerical solver.
{"title":"High asymptotic order numerical methods for highly oscillatory ODEs with large initial data","authors":"Zhongli Liu , Hongjiong Tian","doi":"10.1016/j.aml.2024.109365","DOIUrl":"10.1016/j.aml.2024.109365","url":null,"abstract":"<div><div>In this paper, we propose high asymptotic order numerical methods for solving highly oscillatory second order ODEs with large initial data, where the total energy of the system becomes unbounded as the oscillation frequency grows. The existing asymptotic-numerical solvers are especially designed for the classical energy bounded oscillatory equations, offering no insight into their performance with energy unbounded case. Based on the asymptotic expansion of the solution in the inverse powers of the oscillatory parameter, we propose an asymptotic numerical integrator to solve this class of highly oscillatory ODEs and discuss the computational efficiency for the case of polynomials. One numerical example is given to show the efficiency and accuracy of our proposed asymptotic-numerical solver.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109365"},"PeriodicalIF":2.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656554","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}
Pub Date : 2024-11-09DOI: 10.1016/j.aml.2024.109364
Félix del Teso , Łukasz Płociniczak
We establish uniform error bounds of the L1 discretization of the Caputo derivative of Hölder continuous functions. The result can be understood as: error = degree of smoothness - order of the derivative. We present an elementary proof and illustrate its optimality with numerical examples.
{"title":"A note on the L1 discretization error for the Caputo derivative in Hölder spaces","authors":"Félix del Teso , Łukasz Płociniczak","doi":"10.1016/j.aml.2024.109364","DOIUrl":"10.1016/j.aml.2024.109364","url":null,"abstract":"<div><div>We establish uniform error bounds of the L1 discretization of the Caputo derivative of Hölder continuous functions. The result can be understood as: <em>error = degree of smoothness - order of the derivative.</em> We present an elementary proof and illustrate its optimality with numerical examples.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109364"},"PeriodicalIF":2.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656783","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}
Pub Date : 2024-11-09DOI: 10.1016/j.aml.2024.109362
Xi-Hu Wu , Yi-Tian Gao
Under investigated in this paper is a Lakshmanan-Porsezian-Daniel equation that describes the nonlinear spin excitations in a (1+1)-dimensional isotropic biquadratic Heisenberg ferromagnetic spin chain with the octupole-dipole interaction or the propagation of the ultrashort pulses in a long-distance and high-speed optical fiber transmission system. Under certain parameter conditions, we simultaneously take the multi-pole phenomena and breather-to-soliton transitions into account, then utilize the second-order generalized Darboux transformation to derive the double-pole anti-dark solitons and graphically illustrate them. Asymptotic analysis is conducted to examine the interaction properties of double-pole anti-dark solitons, including their characteristic lines, amplitudes, phase shifts, slopes and position differences. Unlike the double-pole anti-dark solitons found in the Hirota equation, the ones in this study exhibit a distinct feature: Different soliton components share the same amplitude.
{"title":"Double-pole anti-dark solitons for a Lakshmanan-Porsezian-Daniel equation in an optical fiber or a ferromagnetic spin chain","authors":"Xi-Hu Wu , Yi-Tian Gao","doi":"10.1016/j.aml.2024.109362","DOIUrl":"10.1016/j.aml.2024.109362","url":null,"abstract":"<div><div>Under investigated in this paper is a Lakshmanan-Porsezian-Daniel equation that describes the nonlinear spin excitations in a (1+1)-dimensional isotropic biquadratic Heisenberg ferromagnetic spin chain with the octupole-dipole interaction or the propagation of the ultrashort pulses in a long-distance and high-speed optical fiber transmission system. Under certain parameter conditions, we simultaneously take the multi-pole phenomena and breather-to-soliton transitions into account, then utilize the second-order generalized Darboux transformation to derive the double-pole anti-dark solitons and graphically illustrate them. Asymptotic analysis is conducted to examine the interaction properties of double-pole anti-dark solitons, including their characteristic lines, amplitudes, phase shifts, slopes and position differences. Unlike the double-pole anti-dark solitons found in the Hirota equation, the ones in this study exhibit a distinct feature: Different soliton components share the same amplitude.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109362"},"PeriodicalIF":2.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705965","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}
Pub Date : 2024-11-09DOI: 10.1016/j.aml.2024.109367
Xiaotong Mu, Jinyi Sun
The paper is concerned with the three-dimensional micropolar fluid equations. By using the successive approximation and Littlewood–Paley theory, we prove existence and uniqueness of time-periodic mild solutions of the three-dimensional micropolar fluid equations with external forces in Besov spaces.
{"title":"Time-periodic mild solutions to the three-dimensional micropolar fluid equations","authors":"Xiaotong Mu, Jinyi Sun","doi":"10.1016/j.aml.2024.109367","DOIUrl":"10.1016/j.aml.2024.109367","url":null,"abstract":"<div><div>The paper is concerned with the three-dimensional micropolar fluid equations. By using the successive approximation and Littlewood–Paley theory, we prove existence and uniqueness of time-periodic mild solutions of the three-dimensional micropolar fluid equations with external forces in Besov spaces.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109367"},"PeriodicalIF":2.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656551","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}
Pub Date : 2024-11-09DOI: 10.1016/j.aml.2024.109363
Deqin Qiu , Yongshuai Zhang , Wei Liu
Several novel rational solutions with nonzero boundary condition for the Kundu equation, which is an important physical model, are derived using the technique of generalized Darboux transformation. It is the first time that a systemic analysis has been conducted on such rational solutions for the Kundu equation. For the 1-order rational solutions with nonzero boundary conditions, our findings reveal that three parameters, , , and , which are associated with the effects of self-steepening, self-phase modulation, and quintic nonlinearity in the Kundu equation, can result in four distinct states for case B and five distinct states for case C, all corresponding to rational solutions with nonzero boundary conditions.
利用广义达尔布克斯变换技术,为重要物理模型昆都方程导出了几种具有非零边界条件的新型有理解。这是首次对昆杜方程的此类有理解进行系统分析。对于具有非零边界条件的一阶有理解,我们的研究结果表明,与昆杜方程中的自膨胀、自相位调制和五次非线性效应相关的三个参数 a、b 和 β 可导致情况 B 中的四种不同状态和情况 C 中的五种不同状态,它们都对应于具有非零边界条件的有理解。
{"title":"State transitions for the rational solutions of Kundu equation with non-zero boundary conditions","authors":"Deqin Qiu , Yongshuai Zhang , Wei Liu","doi":"10.1016/j.aml.2024.109363","DOIUrl":"10.1016/j.aml.2024.109363","url":null,"abstract":"<div><div>Several novel rational solutions with nonzero boundary condition for the Kundu equation, which is an important physical model, are derived using the technique of generalized Darboux transformation. It is the first time that a systemic analysis has been conducted on such rational solutions for the Kundu equation. For the 1-order rational solutions with nonzero boundary conditions, our findings reveal that three parameters, <span><math><mi>a</mi></math></span>, <span><math><mi>b</mi></math></span>, and <span><math><mi>β</mi></math></span>, which are associated with the effects of self-steepening, self-phase modulation, and quintic nonlinearity in the Kundu equation, can result in four distinct states for case B and five distinct states for case C, all corresponding to rational solutions with nonzero boundary conditions.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109363"},"PeriodicalIF":2.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656556","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}
Pub Date : 2024-11-09DOI: 10.1016/j.aml.2024.109366
Songbai Guo , Min He , Fuxiang Li
A time-delayed dengue virus transmission model has been developed, which takes into account vaccination failure and the presence of exposed mosquitoes. This model also incorporates the survival probability of infected individuals during the incubation period to provide a clearer understanding of how latency affects the control reproduction number . Furthermore, by employing the Lyapunov functional approach, we establish the global asymptotic stability of equilibria in relation to . The results indicate that the disease-free equilibrium is globally asymptotically stable if and only if , whereas the endemic equilibrium is globally asymptotically stable if and only if .
{"title":"Threshold dynamics of a time-delayed dengue virus infection model incorporating vaccination failure and exposed mosquitoes","authors":"Songbai Guo , Min He , Fuxiang Li","doi":"10.1016/j.aml.2024.109366","DOIUrl":"10.1016/j.aml.2024.109366","url":null,"abstract":"<div><div>A time-delayed dengue virus transmission model has been developed, which takes into account vaccination failure and the presence of exposed mosquitoes. This model also incorporates the survival probability of infected individuals during the incubation period to provide a clearer understanding of how latency affects the control reproduction number <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>. Furthermore, by employing the Lyapunov functional approach, we establish the global asymptotic stability of equilibria in relation to <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>. The results indicate that the disease-free equilibrium <span><math><msup><mrow><mi>T</mi></mrow><mrow><mn>0</mn></mrow></msup></math></span> is globally asymptotically stable if and only if <span><math><mrow><msub><mrow><mi>R</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>≤</mo><mn>1</mn></mrow></math></span>, whereas the endemic equilibrium <span><math><msup><mrow><mi>T</mi></mrow><mrow><mo>∗</mo></mrow></msup></math></span> is globally asymptotically stable if and only if <span><math><mrow><msub><mrow><mi>R</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>></mo><mn>1</mn></mrow></math></span>.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109366"},"PeriodicalIF":2.9,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656553","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}
Pub Date : 2024-11-06DOI: 10.1016/j.aml.2024.109371
Miao Du , Xiaohan Gao
In this paper, we focus on a class of non-autonomous Kirchhoff equations, that is, in , where are constants, is unknown and appears as a Lagrange multiplier, and is a potential function. Under certain assumptions on the potential , the concentration behavior of normalized ground state solutions is analyzed by using variational methods.
本文主要研究一类非自治基尔霍夫方程,即 R3 中的-(a+b∫R3|∇u|2dx)Δu-λu=K(x)|u|p-2u,其中 a、b>0 为常数,λ∈R 为未知数并作为拉格朗日乘数出现,2<p<6,K:R3→R 为势函数。在电势 K 的某些假设条件下,利用变分法分析了归一化基态解的浓度行为。
{"title":"On the mass concentration of normalized ground state solutions for non-autonomous Kirchhoff equations","authors":"Miao Du , Xiaohan Gao","doi":"10.1016/j.aml.2024.109371","DOIUrl":"10.1016/j.aml.2024.109371","url":null,"abstract":"<div><div>In this paper, we focus on a class of non-autonomous Kirchhoff equations, that is, <span><math><mrow><mo>−</mo><mrow><mo>(</mo><mi>a</mi><mo>+</mo><mi>b</mi><msub><mrow><mo>∫</mo></mrow><mrow><msup><mrow><mi>R</mi></mrow><mrow><mn>3</mn></mrow></msup></mrow></msub><msup><mrow><mrow><mo>|</mo><mo>∇</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mn>2</mn></mrow></msup><mspace></mspace><mtext>d</mtext><mi>x</mi><mo>)</mo></mrow><mi>Δ</mi><mi>u</mi><mo>−</mo><mi>λ</mi><mi>u</mi><mo>=</mo><mi>K</mi><mrow><mo>(</mo><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>a</mi><mo>,</mo><mi>b</mi><mo>></mo><mn>0</mn></mrow></math></span> are constants, <span><math><mrow><mi>λ</mi><mo>∈</mo><mi>R</mi></mrow></math></span> is unknown and appears as a Lagrange multiplier, <span><math><mrow><mn>2</mn><mo><</mo><mi>p</mi><mo><</mo><mn>6</mn></mrow></math></span> and <span><math><mrow><mi>K</mi><mo>:</mo><msup><mrow><mi>R</mi></mrow><mrow><mn>3</mn></mrow></msup><mo>→</mo><mi>R</mi></mrow></math></span> is a potential function. Under certain assumptions on the potential <span><math><mi>K</mi></math></span>, the concentration behavior of normalized ground state solutions is analyzed by using variational methods.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109371"},"PeriodicalIF":2.9,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656606","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}
Pub Date : 2024-11-06DOI: 10.1016/j.aml.2024.109372
Hui Huang, Hicham Kouhkouh
A self-interacting dynamics that mimics the standard Consensus-Based Optimization (CBO) model is introduced. This single-particle dynamics is shown to converge to a unique invariant measure that approximates the global minimum of a given function. As an application, its connection to CBO with Personal Best introduced by C. Totzeck and M.-T. Wolfram (Math. Biosci. Eng., 2020) has been established.
本文介绍了一种模仿标准共识优化(CBO)模型的自相互作用动力学。研究表明,这种单粒子动力学会收敛到一个独特的不变度量,该度量近似于给定函数的全局最小值。作为应用,C. Totzeck 和 M.-T. Wolfram 介绍了它与 CBO 与 Personal Best 的联系(Math.Wolfram (Math. Biosci. Eng., 2020)提出的CBO与Personal Best的联系。
{"title":"Self-interacting CBO: Existence, uniqueness, and long-time convergence","authors":"Hui Huang, Hicham Kouhkouh","doi":"10.1016/j.aml.2024.109372","DOIUrl":"10.1016/j.aml.2024.109372","url":null,"abstract":"<div><div>A self-interacting dynamics that mimics the standard Consensus-Based Optimization (CBO) model is introduced. This single-particle dynamics is shown to converge to a unique invariant measure that approximates the global minimum of a given function. As an application, its connection to CBO with Personal Best introduced by C. Totzeck and M.-T. Wolfram (Math. Biosci. Eng., 2020) has been established.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109372"},"PeriodicalIF":2.9,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656607","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}
Pub Date : 2024-11-06DOI: 10.1016/j.aml.2024.109361
Tobias Black
<div><div>In this paper we consider a chemotaxis system with signal consumption and degenerate diffusion of the form <span><span><span><math><mfenced><mrow><mtable><mtr><mtd></mtd><mtd><msub><mrow><mi>u</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mo>∇</mo><mi>⋅</mi><mrow><mo>(</mo><mi>D</mi><mrow><mo>(</mo><mi>u</mi><mo>)</mo></mrow><mo>∇</mo><mi>u</mi><mo>−</mo><mi>u</mi><mi>S</mi><mrow><mo>(</mo><mi>u</mi><mo>)</mo></mrow><mo>∇</mo><mi>v</mi><mo>)</mo></mrow><mo>+</mo><mi>f</mi><mrow><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo></mrow><mo>,</mo><mspace></mspace></mtd></mtr><mtr><mtd></mtd><mtd><msub><mrow><mi>v</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mi>Δ</mi><mi>v</mi><mo>−</mo><mi>u</mi><mi>v</mi><mo>,</mo><mspace></mspace></mtd></mtr><mtr><mtd></mtd></mtr></mtable></mrow></mfenced></math></span></span></span>in a bounded domain <span><math><mrow><mi>Ω</mi><mo>⊂</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>N</mi></mrow></msup></mrow></math></span> with smooth boundary subjected to no-flux and homogeneous Neumann boundary conditions. Herein, the diffusion coefficient <span><math><mrow><mi>D</mi><mo>∈</mo><msup><mrow><mi>C</mi></mrow><mrow><mn>0</mn></mrow></msup><mrow><mo>(</mo><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>)</mo></mrow><mo>∩</mo><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup><mrow><mo>(</mo><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>)</mo></mrow></mrow></math></span> is assumed to satisfy <span><math><mrow><mi>D</mi><mrow><mo>(</mo><mn>0</mn><mo>)</mo></mrow><mo>=</mo><mn>0</mn></mrow></math></span>, <span><math><mrow><mi>D</mi><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mo>></mo><mn>0</mn></mrow></math></span> on <span><math><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow></math></span>, <span><math><mrow><msup><mrow><mi>D</mi></mrow><mrow><mo>′</mo></mrow></msup><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mo>≥</mo><mn>0</mn></mrow></math></span> on <span><math><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow></math></span> and that there are <span><math><mrow><msub><mrow><mi>s</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>></mo><mn>0</mn></mrow></math></span>, <span><math><mrow><mi>p</mi><mo>></mo><mn>1</mn></mrow></math></span> and <span><math><mrow><msub><mrow><mi>C</mi></mrow><mrow><mi>D</mi></mrow></msub><mo>></mo><mn>0</mn></mrow></math></span> such that <span><span><span><math><mrow><mi>s</mi><msup><mrow><mi>D</mi></mrow><mrow><mo>′</mo></mrow></msup><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mo>≤</mo><msub><mrow><mi>C</mi></mrow><mrow><mi>D</mi></mrow></msub><mi>D</mi><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mspace></mspace><mtext>and</mtext><mspace></mspace><msub><mrow><mi>C</mi></mrow><mrow><mi>D</mi></mrow></msub><msup><mrow><mi>s</mi></mrow><mrow><mi>p</mi><mo>−</mo><mn>1</mn></mrow></msup><mo>≤</mo><mi>D</mi><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mspace></mspace><mtext>for</mtext><mi>s<
本文考虑了一个具有信号消耗和退化扩散的趋化系统,其形式为 ut=∇-(D(u)∇u-uS(u)∇v)+f(u,v),vt=Δv-uv,该系统在一个边界光滑的有界域 Ω⊂RN中,受无流体和同质新曼边界条件的约束。这里,假设扩散系数 D∈C0([0,∞))∩C2((0,∞)) 满足 D(0)=0, D(s)>;0 on (0,∞), D′(s)≥0 on (0,∞) and that there are s0>0, p>1 and CD>0 such that sD′(s)≤CDD(s)andCDsp-1≤D(s)fors∈[0,s0].灵敏度函数 S∈C2([0,∞)) 和源项 f∈C1([0,∞)×[0,∞)) 假定为非负。我们证明,对于所有满足 u0≥δ0>0 和 v0⁄≡0 的适当规则初始数据(u0,v0),都存在一个时域经典解,并且--尽管在 0 处存在退行性--该解满足一个扩展性准则,其形式为:Tmax=∞,或 Lim suptTmax‖u(⋅,t)‖L∞(Ω)=∞ 。此外,作为分析的一个副产品,我们证明了在Ω×(0,T)上的经典解在所有 t∈(0,T)条件下服从‖u(⋅,t)‖L∞(Ω)≤Mu,并且从上述初始数据 (u0,v0) 出发,在整个Ω×(0,T)上保持严格的正解性,也就是说,可以找到δu=δu(Ω)=∞。结果表明,在这些具有退化扩散的趋化系统中,在炸毁时间之前不可能形成死核。
{"title":"Absence of dead-core formations in chemotaxis systems with degenerate diffusion","authors":"Tobias Black","doi":"10.1016/j.aml.2024.109361","DOIUrl":"10.1016/j.aml.2024.109361","url":null,"abstract":"<div><div>In this paper we consider a chemotaxis system with signal consumption and degenerate diffusion of the form <span><span><span><math><mfenced><mrow><mtable><mtr><mtd></mtd><mtd><msub><mrow><mi>u</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mo>∇</mo><mi>⋅</mi><mrow><mo>(</mo><mi>D</mi><mrow><mo>(</mo><mi>u</mi><mo>)</mo></mrow><mo>∇</mo><mi>u</mi><mo>−</mo><mi>u</mi><mi>S</mi><mrow><mo>(</mo><mi>u</mi><mo>)</mo></mrow><mo>∇</mo><mi>v</mi><mo>)</mo></mrow><mo>+</mo><mi>f</mi><mrow><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo></mrow><mo>,</mo><mspace></mspace></mtd></mtr><mtr><mtd></mtd><mtd><msub><mrow><mi>v</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mi>Δ</mi><mi>v</mi><mo>−</mo><mi>u</mi><mi>v</mi><mo>,</mo><mspace></mspace></mtd></mtr><mtr><mtd></mtd></mtr></mtable></mrow></mfenced></math></span></span></span>in a bounded domain <span><math><mrow><mi>Ω</mi><mo>⊂</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>N</mi></mrow></msup></mrow></math></span> with smooth boundary subjected to no-flux and homogeneous Neumann boundary conditions. Herein, the diffusion coefficient <span><math><mrow><mi>D</mi><mo>∈</mo><msup><mrow><mi>C</mi></mrow><mrow><mn>0</mn></mrow></msup><mrow><mo>(</mo><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>)</mo></mrow><mo>∩</mo><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup><mrow><mo>(</mo><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>)</mo></mrow></mrow></math></span> is assumed to satisfy <span><math><mrow><mi>D</mi><mrow><mo>(</mo><mn>0</mn><mo>)</mo></mrow><mo>=</mo><mn>0</mn></mrow></math></span>, <span><math><mrow><mi>D</mi><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mo>></mo><mn>0</mn></mrow></math></span> on <span><math><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow></math></span>, <span><math><mrow><msup><mrow><mi>D</mi></mrow><mrow><mo>′</mo></mrow></msup><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mo>≥</mo><mn>0</mn></mrow></math></span> on <span><math><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow></math></span> and that there are <span><math><mrow><msub><mrow><mi>s</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>></mo><mn>0</mn></mrow></math></span>, <span><math><mrow><mi>p</mi><mo>></mo><mn>1</mn></mrow></math></span> and <span><math><mrow><msub><mrow><mi>C</mi></mrow><mrow><mi>D</mi></mrow></msub><mo>></mo><mn>0</mn></mrow></math></span> such that <span><span><span><math><mrow><mi>s</mi><msup><mrow><mi>D</mi></mrow><mrow><mo>′</mo></mrow></msup><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mo>≤</mo><msub><mrow><mi>C</mi></mrow><mrow><mi>D</mi></mrow></msub><mi>D</mi><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mspace></mspace><mtext>and</mtext><mspace></mspace><msub><mrow><mi>C</mi></mrow><mrow><mi>D</mi></mrow></msub><msup><mrow><mi>s</mi></mrow><mrow><mi>p</mi><mo>−</mo><mn>1</mn></mrow></msup><mo>≤</mo><mi>D</mi><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow><mspace></mspace><mtext>for</mtext><mi>s<","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109361"},"PeriodicalIF":2.9,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656552","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}
Pub Date : 2024-11-04DOI: 10.1016/j.aml.2024.109359
Spencer Locke, Dmitry E. Pelinovsky
Babenko’s equation describes traveling water waves in holomorphic coordinates. It has been used in the past to obtain properties of Stokes waves with smooth profiles analytically and numerically. We show in the deep-water limit that properties of Stokes waves with peaked profiles can also be recovered from the same Babenko’s equation. In order to develop the local analysis of singularities, we rewrite Babenko’s equation as a fixed-point problem near the maximal elevation level. As a by-product, our results rule out a corner point singularity in the holomorphic coordinates, which has been obtained in a local version of Babenko’s equation.
{"title":"Peaked Stokes waves as solutions of Babenko’s equation","authors":"Spencer Locke, Dmitry E. Pelinovsky","doi":"10.1016/j.aml.2024.109359","DOIUrl":"10.1016/j.aml.2024.109359","url":null,"abstract":"<div><div>Babenko’s equation describes traveling water waves in holomorphic coordinates. It has been used in the past to obtain properties of Stokes waves with smooth profiles analytically and numerically. We show in the deep-water limit that properties of Stokes waves with peaked profiles can also be recovered from the same Babenko’s equation. In order to develop the local analysis of singularities, we rewrite Babenko’s equation as a fixed-point problem near the maximal elevation level. As a by-product, our results rule out a corner point singularity in the holomorphic coordinates, which has been obtained in a local version of Babenko’s equation.</div></div>","PeriodicalId":55497,"journal":{"name":"Applied Mathematics Letters","volume":"161 ","pages":"Article 109359"},"PeriodicalIF":2.9,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656782","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}