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Existence and uniqueness of time-periodic solutions to the Oberbeck–Boussinesq system Oberbeck-Boussinesq系统时间周期解的存在唯一性
IF 1.8 3区 数学
Nonlinear Analysis-Real World Applications Pub Date : 2025-07-29 DOI: 10.1016/j.nonrwa.2025.104461
Tomoyuki Nakatsuka
{"title":"Existence and uniqueness of time-periodic solutions to the Oberbeck–Boussinesq system","authors":"Tomoyuki Nakatsuka","doi":"10.1016/j.nonrwa.2025.104461","DOIUrl":"10.1016/j.nonrwa.2025.104461","url":null,"abstract":"<div><div>This paper is devoted to the study of the time-periodic problem for the Oberbeck–Boussinesq system in the whole space. Our investigation is based on the reformulation of the time-periodic problem and does not depend on the analysis of the initial value problem. We construct a time-periodic solution with more information on its structure than the solutions in preceding studies. We also prove that our solution, small in an appropriate sense, is unique in the class of solutions having slightly more regularity.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"88 ","pages":"Article 104461"},"PeriodicalIF":1.8,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722113","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}
引用次数: 0
Continuum limit of fourth-order Schrödinger equations on the lattice 晶格上四阶Schrödinger方程的连续统极限
IF 1 2区 数学
Journal of the London Mathematical Society-Second Series Pub Date : 2025-07-29 DOI: 10.1112/jlms.70247
Jiawei Cheng, Bobo Hua
{"title":"Continuum limit of fourth-order Schrödinger equations on the lattice","authors":"Jiawei Cheng,&nbsp;Bobo Hua","doi":"10.1112/jlms.70247","DOIUrl":"https://doi.org/10.1112/jlms.70247","url":null,"abstract":"<p>In this paper, we consider the discrete fourth-order Schrödinger equation on the lattice <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>h</mi>\u0000 <msup>\u0000 <mi>Z</mi>\u0000 <mn>2</mn>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$hmathbb {Z}^2$</annotation>\u0000 </semantics></math>. Uniform Strichartz estimates are established by analyzing frequency localized oscillatory integrals with the method of stationary phase and applying Littlewood–Paley inequalities. As an application, we obtain the precise rate of <span></span><math>\u0000 <semantics>\u0000 <msup>\u0000 <mi>L</mi>\u0000 <mn>2</mn>\u0000 </msup>\u0000 <annotation>$L^2$</annotation>\u0000 </semantics></math> convergence from the solutions of discrete semilinear equations to those of the corresponding equations on the Euclidean plane <span></span><math>\u0000 <semantics>\u0000 <msup>\u0000 <mi>R</mi>\u0000 <mn>2</mn>\u0000 </msup>\u0000 <annotation>$mathbb {R}^2$</annotation>\u0000 </semantics></math> in the continuum limit <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>h</mi>\u0000 <mo>→</mo>\u0000 <mn>0</mn>\u0000 </mrow>\u0000 <annotation>$h rightarrow 0$</annotation>\u0000 </semantics></math>.</p>","PeriodicalId":49989,"journal":{"name":"Journal of the London Mathematical Society-Second Series","volume":"112 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716597","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
Q-points, selective ultrafilters, and idempotents, with an application to choiceless set theory q点,选择性超滤波器,和幂等函数,在无选择集合理论中的应用
IF 1 2区 数学
Journal of the London Mathematical Society-Second Series Pub Date : 2025-07-29 DOI: 10.1112/jlms.70249
David Fernández-Bretón, Jareb Navarro-Castillo, Jesús A. Soria-Rojas
{"title":"Q-points, selective ultrafilters, and idempotents, with an application to choiceless set theory","authors":"David Fernández-Bretón,&nbsp;Jareb Navarro-Castillo,&nbsp;Jesús A. Soria-Rojas","doi":"10.1112/jlms.70249","DOIUrl":"https://doi.org/10.1112/jlms.70249","url":null,"abstract":"&lt;p&gt;We study ultrafilters from the perspective of the algebra in the Čech–Stone compactification of the natural numbers, and idempotent elements therein. The first two results that we prove establish that, if &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;annotation&gt;$p$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; is a Q-point (resp., a selective ultrafilter) and &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;msup&gt;\u0000 &lt;mi&gt;F&lt;/mi&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;/msup&gt;\u0000 &lt;annotation&gt;$mathcal F^p$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; (resp., &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;msup&gt;\u0000 &lt;mi&gt;G&lt;/mi&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;/msup&gt;\u0000 &lt;annotation&gt;$mathcal G^p$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) is the smallest family containing &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;annotation&gt;$p$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and closed under iterated sums (resp., closed under Blass–Frolík sums and Rudin–Keisler images), then &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;msup&gt;\u0000 &lt;mi&gt;F&lt;/mi&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;/msup&gt;\u0000 &lt;annotation&gt;$mathcal F^p$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; (resp., &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;msup&gt;\u0000 &lt;mi&gt;G&lt;/mi&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;/msup&gt;\u0000 &lt;annotation&gt;$mathcal G^p$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) contains no idempotent elements. The second of these results about a selective ultrafilter has the following interesting consequence: assuming a conjecture of Blass, in models of the form &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;L&lt;/mi&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 &lt;mi&gt;R&lt;/mi&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;mo&gt;[&lt;/mo&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;mo&gt;]&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$mathnormal {mathbf {L}(mathbb {R})}[p]$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; where &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;L&lt;/mi&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 &lt;mi&gt;R&lt;/mi&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$mathnormal {mathbf {L}(mathbb {R})}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; is a Solovay model (of &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mi&gt;ZF&lt;/mi&gt;\u0000 &lt;annotation&gt;$mathnormal {mathsf {ZF}}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; without choice) and &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mi&gt;p&lt;/mi&gt;\u0000 &lt;annotation&gt;$p$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; is a selective ultrafilter, there are no idempotent elements. In particular, the theory &lt;sp","PeriodicalId":49989,"journal":{"name":"Journal of the London Mathematical Society-Second Series","volume":"112 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716702","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
Perfect k-matching, k-factor-critical and Aα-spectral radius 完美的k匹配,k因子临界和a α谱半径
IF 1 3区 数学
Discrete Applied Mathematics Pub Date : 2025-07-29 DOI: 10.1016/j.dam.2025.07.020
Mengyuan Niu , Shanshan Zhang , Xiumei Wang
{"title":"Perfect k-matching, k-factor-critical and Aα-spectral radius","authors":"Mengyuan Niu ,&nbsp;Shanshan Zhang ,&nbsp;Xiumei Wang","doi":"10.1016/j.dam.2025.07.020","DOIUrl":"10.1016/j.dam.2025.07.020","url":null,"abstract":"<div><div>A <span><math><mi>k</mi></math></span>-<em>matching</em> of a graph <span><math><mi>G</mi></math></span> is a function <span><math><mi>f</mi></math></span>: <span><math><mrow><mi>E</mi><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>→</mo><mrow><mo>{</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>,</mo><mo>…</mo><mo>,</mo><mi>k</mi><mo>}</mo></mrow></mrow></math></span> satisfying <span><math><mrow><munder><mrow><mo>∑</mo></mrow><mrow><mi>e</mi><mo>∈</mo><mi>∂</mi><mrow><mo>(</mo><mi>v</mi><mo>)</mo></mrow></mrow></munder><mi>f</mi><mrow><mo>(</mo><mi>e</mi><mo>)</mo></mrow><mo>≤</mo><mi>k</mi></mrow></math></span> for any vertex <span><math><mrow><mi>v</mi><mo>∈</mo><mi>V</mi><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span>. A <span><math><mi>k</mi></math></span>-matching of a graph <span><math><mi>G</mi></math></span> is <em>perfect</em> if <span><math><mrow><munder><mrow><mo>∑</mo></mrow><mrow><mi>e</mi><mo>∈</mo><mi>∂</mi><mrow><mo>(</mo><mi>v</mi><mo>)</mo></mrow></mrow></munder><mi>f</mi><mrow><mo>(</mo><mi>e</mi><mo>)</mo></mrow><mo>=</mo><mi>k</mi></mrow></math></span> for every vertex <span><math><mrow><mi>v</mi><mo>∈</mo><mi>V</mi><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span>. A graph <span><math><mi>G</mi></math></span> of order <span><math><mi>n</mi></math></span> is <em>k-factor-critical</em> if the removal of any set of <span><math><mi>k</mi></math></span> vertices of <span><math><mi>G</mi></math></span> results in a graph with a perfect matching. Let <span><math><mrow><mi>A</mi><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span> and <span><math><mrow><mi>D</mi><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span> be the adjacency matrix and the degree diagonal matrix of <span><math><mi>G</mi></math></span>. For <span><math><mrow><mi>α</mi><mo>∈</mo><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow></mrow></math></span>, Nikiforov <span><math><mrow><mo>(</mo><mn>2017</mn><mo>)</mo></mrow></math></span> introduced the <span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span>-matrix of G as follows: <span><math><mrow><msub><mrow><mi>A</mi></mrow><mrow><mi>α</mi></mrow></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>=</mo><mi>α</mi><mi>D</mi><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>+</mo><mrow><mo>(</mo><mn>1</mn><mo>−</mo><mi>α</mi><mo>)</mo></mrow><mi>A</mi><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>.</mo></mrow></math></span> In this paper, according to the <span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span>-spectral radius, we provide two sufficient conditions to ensure that a graph is <span><math><mi>k</mi></math></span>-factor-critical and has a perfect <span><math><mi>k</mi></math></span>-matching, respectively.</div></div>","PeriodicalId":50573,"journal":{"name":"Discrete Applied Mathematics","volume":"376 ","pages":"Pages 384-393"},"PeriodicalIF":1.0,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721096","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}
引用次数: 0
Indivisibility for classes of graphs 图类的不可分性
IF 0.7 3区 数学
Discrete Mathematics Pub Date : 2025-07-29 DOI: 10.1016/j.disc.2025.114703
Vincent Guingona , Felix Nusbaum , Zain Padamsee , Miriam Parnes , Christian Pippin , Ava Zinman
{"title":"Indivisibility for classes of graphs","authors":"Vincent Guingona ,&nbsp;Felix Nusbaum ,&nbsp;Zain Padamsee ,&nbsp;Miriam Parnes ,&nbsp;Christian Pippin ,&nbsp;Ava Zinman","doi":"10.1016/j.disc.2025.114703","DOIUrl":"10.1016/j.disc.2025.114703","url":null,"abstract":"<div><div>We examine indivisibility for classes of graphs. We show that the class of hereditarily <em>α</em>-sparse graphs is indivisible if and only if <span><math><mi>α</mi><mo>&gt;</mo><mn>2</mn></math></span>. Additionally, we show that the following classes of graphs are indivisible: perfect graphs, cographs, and chordal graphs, and the following classes of graphs are not indivisible: threshold graphs, split graphs, and distance-hereditary graphs.</div></div>","PeriodicalId":50572,"journal":{"name":"Discrete Mathematics","volume":"349 2","pages":"Article 114703"},"PeriodicalIF":0.7,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721907","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}
引用次数: 0
On the complexity of p-order cone programs 论p阶锥规划的复杂性
IF 1.8 2区 数学
Journal of Complexity Pub Date : 2025-07-29 DOI: 10.1016/j.jco.2025.101979
Víctor Blanco , Victor Magron , Miguel Martínez-Antón
{"title":"On the complexity of p-order cone programs","authors":"Víctor Blanco ,&nbsp;Victor Magron ,&nbsp;Miguel Martínez-Antón","doi":"10.1016/j.jco.2025.101979","DOIUrl":"10.1016/j.jco.2025.101979","url":null,"abstract":"<div><div>This manuscript explores novel complexity results for the feasibility problem over <em>p</em>-order cones, extending the foundational work of Porkolab and Khachiyan (1997) <span><span>[30]</span></span>. By leveraging the intrinsic structure of <em>p</em>-order cones, we derive refined complexity bounds that surpass those obtained via standard semidefinite programming reformulations. Our analysis not only improves theoretical bounds but also provides practical insights into the computational efficiency of solving such problems. In addition to establishing complexity results, we derive explicit bounds for solutions when the feasibility problem admits one. For infeasible instances, we analyze their discrepancy quantifying the degree of infeasibility. Finally, we examine specific cases of interest, highlighting scenarios where the geometry of <em>p</em>-order cones or problem structure yields further computational simplifications. These findings contribute to both the theoretical understanding and practical tractability of optimization problems involving <em>p</em>-order cones.</div></div>","PeriodicalId":50227,"journal":{"name":"Journal of Complexity","volume":"91 ","pages":"Article 101979"},"PeriodicalIF":1.8,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724397","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
Reverse order law for NDMPI of dual complex matrices and its applications 对偶复矩阵NDMPI的逆序律及其应用
IF 1.1 4区 数学
Linear & Multilinear Algebra Pub Date : 2025-07-29 DOI: 10.1080/03081087.2025.2537965
Tikesh Verma, Amit Kumar, Debasisha Mishra
{"title":"Reverse order law for NDMPI of dual complex matrices and its applications","authors":"Tikesh Verma, Amit Kumar, Debasisha Mishra","doi":"10.1080/03081087.2025.2537965","DOIUrl":"https://doi.org/10.1080/03081087.2025.2537965","url":null,"abstract":"","PeriodicalId":49905,"journal":{"name":"Linear & Multilinear Algebra","volume":"7 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144737009","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
A topological algorithm for the Fourier transform of Stokes data at infinity 无穷远处Stokes数据傅里叶变换的拓扑算法
IF 1 2区 数学
Journal of the London Mathematical Society-Second Series Pub Date : 2025-07-29 DOI: 10.1112/jlms.70253
Jean Douçot, Andreas Hohl
{"title":"A topological algorithm for the Fourier transform of Stokes data at infinity","authors":"Jean Douçot,&nbsp;Andreas Hohl","doi":"10.1112/jlms.70253","DOIUrl":"https://doi.org/10.1112/jlms.70253","url":null,"abstract":"<p>We give a topological description of the behaviour of Stokes matrices under the Fourier transform from infinity to infinity in a large number of cases of one level. This explicit, algorithmic statement is obtained by building on a recent result of T. Mochizuki about the Fourier transform of Stokes data of irregular connections on the Riemann sphere and by using the language of Stokes local systems due to P. Boalch. In particular, this induces explicit isomorphisms between wild character varieties, in a much larger range of examples than those for which such isomorphisms have previously been written down. We conjecture that these isomorphisms are compatible with the quasi-Hamiltonian structure on the wild character varieties.</p>","PeriodicalId":49989,"journal":{"name":"Journal of the London Mathematical Society-Second Series","volume":"112 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1112/jlms.70253","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716703","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
Synergistic effects of feedback regulation and vegetation internal competition on vegetation patterns in semi-arid environments 半干旱环境下反馈调节与植被内部竞争对植被格局的协同效应
IF 5.6 1区 数学
Chaos Solitons & Fractals Pub Date : 2025-07-29 DOI: 10.1016/j.chaos.2025.116912
Feiran Li, Ruizhi Yang, Liqin Liu
{"title":"Synergistic effects of feedback regulation and vegetation internal competition on vegetation patterns in semi-arid environments","authors":"Feiran Li,&nbsp;Ruizhi Yang,&nbsp;Liqin Liu","doi":"10.1016/j.chaos.2025.116912","DOIUrl":"10.1016/j.chaos.2025.116912","url":null,"abstract":"<div><div>Against the backdrop of global aridification, the spatial self-organization of vegetation in semi-arid regions is critical to ecosystem stability. This study employs mathematical modeling to unravel the synergistic effects of soil–water diffusion feedback (<span><math><mi>β</mi></math></span>) and vegetation internal competition (<span><math><mi>σ</mi></math></span>) on pattern formation. Extending the Klausmeier framework, we integrate a cross-diffusion term <span><math><mrow><mi>Δ</mi><mrow><mo>(</mo><mi>w</mi><mo>−</mo><mi>β</mi><mi>n</mi><mo>)</mo></mrow></mrow></math></span> for root-driven soil–water feedback and a density-dependent competition term <span><math><mrow><mn>1</mn><mo>+</mo><mi>σ</mi><msup><mrow><mi>n</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span>. Key findings include: (1) Increasing <span><math><mi>β</mi></math></span> drives sequential transitions from homogeneous states to gap, stripe, and spot patterns, while rising <span><math><mi>σ</mi></math></span> induces reverse transitions, revealing their antagonistic roles in stability; (2) Enhanced precipitation promotes the expansion of discrete spots into continuous stripes, eventually forming gaps under water surplus. Root-mediated water uptake balances short-term facilitation and long-term competition, explaining adaptive responses to resource constraints. Spot patterns act as desertification warnings, whereas stripes offer restoration strategies via high water-use efficiency. By merging cross-diffusion and competition mechanisms, this work proposes a theoretical framework for arid land management, linking mechanistic insights to practical solutions against land degradation.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"199 ","pages":"Article 116912"},"PeriodicalIF":5.6,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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
Hybrid computational and ANN-based analysis of heat transfer and bioconvection in Sutterby nanofluid flow across a stretched surface 基于混合计算和人工神经网络的萨特比纳米流体在拉伸表面的传热和生物对流分析
IF 5.6 1区 数学
Chaos Solitons & Fractals Pub Date : 2025-07-29 DOI: 10.1016/j.chaos.2025.116942
M. Waqas Ashraf , M. Israr Ur Rehman , Zhoushun Zheng , Aamir Hamid , Haitao Qi
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