Chaos Solitons & Fractals最新文献

{"title":"Bursting synchronization and excitability of the bi-membrane neuron-like circuit under electromagnetic stimuli","authors":"Huimin Qi ,&nbsp;Fengjun Li ,&nbsp;Fuqiang Wu ,&nbsp;Xinlei An","doi":"10.1016/j.chaos.2025.117836","DOIUrl":"10.1016/j.chaos.2025.117836","url":null,"abstract":"<div><div>Neuronal circuits involving two capacitors have an essential role in exploring biophysical mechanisms and mimicking brain-inspired devices. Given the dual-capacitor effect in nerve cells, we systematically investigate dynamical characteristics of the bi-membrane neuron-like (BMN) circuit subjected to a constant current source and alternating magnetic stimulus based on a magnetoelectric nonlinear metamaterial (MNM). Different from traditional single-membrane designs, the BMN circuit has a variety of rich structure, supporting more complex biological dynamics for enhanced neuromorphic computation. Through theoretical analysis and numerical simulation, it is found that the BMN circuit with an increased constant current exhibits neuronal excitability associated with a Hopf bifurcation. Based on Helmholtz's law, the energy function of the BMN circuit system is verified. Under the alternating magnetic stimulus, the BMN circuit can reproduce a chaotic bursting pattern by using numerical simulation. Finally, a BMN circuit network model with constant current source and alternating magnetic stimulus is constructed under resistive coupling. Using a master stability function (MSF) method, it is demonstrated that the BMN circuit network with chaotic and chaotic bursting patterns can achieve stable synchronization under suitable coupling parameters, and the regulation mechanism of coupling strength is elucidated. This study enriches the dynamic theory of the BMN circuit, providing a theoretical reference and practical guidance for network synchronization control and neuromorphic device design.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117836"},"PeriodicalIF":5.6,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902632","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}

{"title":"Research on the robustness of multi-layer interdependent networks based on edge-preserving strategies","authors":"Yufeng Xie ,&nbsp;Chang Shu ,&nbsp;Shirong Liu ,&nbsp;Shiwen Sun ,&nbsp;Jing Wang ,&nbsp;Pei Ye ,&nbsp;Yadong Yan","doi":"10.1016/j.chaos.2025.117848","DOIUrl":"10.1016/j.chaos.2025.117848","url":null,"abstract":"<div><div>Previous studies on cascade failures in interdependent networks have primarily focused on nodes. However, in real-world scenarios, interactions between networks are established through connecting edges rather than the nodes themselves, leading to the concept of edge-coupled interdependent networks (EIN). In this paper, we extend the model to multilayer edge-coupled interdependent networks (MEIN) by reinforcing a fraction m of the connecting edges. We analyze the phase transition behavior in these reinforced networks. The reinforcement of a subset of edges is shown to lower the critical threshold and alter the nature of the phase transition from first-order to mixed. Our results demonstrate that strategically enhancing a certain proportion of interconnecting edges can significantly improve the robustness of multilayer edge-coupled interdependent networks.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117848"},"PeriodicalIF":5.6,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145902635","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}

{"title":"A novel binary composite similarity measure with optimistic and pessimistic attitudes for evidence fusion","authors":"Haohao Guo ,&nbsp;Xiaobin Xu ,&nbsp;Leilei Chang ,&nbsp;Haiquan Wang ,&nbsp;Runkai Li ,&nbsp;Wanjie Zhou","doi":"10.1016/j.chaos.2025.117782","DOIUrl":"10.1016/j.chaos.2025.117782","url":null,"abstract":"<div><div>In Dempster-Shafer (DS) evidence theory, the basic probability assignment function (i.e., “evidence” provided by an information source) is used to model uncertain information, and Dempster's combination rule is employed to fuse multiple pieces of evidence to obtain a more reliable comprehensive result for decision-making. However, when there is a high degree of conflict between two pieces of evidence, the fused result may be counter-intuitive, thereby deteriorating decision accuracy. Hence, constructing appropriate similarity measures to quantify the degree of conflict between two pieces of evidence becomes crucial for resolving these counter-intuitive outcomes. Currently, traditional similarity measures (<em>S</em>) are predominantly obtained through a linear transformation of evidence distance (<em>d</em>). For instance, the similarity between two pieces of evidence is calculated as “<em>S</em> = 1-<em>d</em>”. Such simplistic “univariate” linear transformations suffer from limitations like insufficient precision and poor adaptability. Therefore, this paper proposes a novel binary composite evidence similarity measure. In the transformation process, two distinct mapping attitudes of “optimistic” and “pessimistic” are considered, and the corresponding parameters are given to adjust to the change trend of the two attitudes. In addition, we theoretically prove that the proposed binary composite measure satisfies the core properties of similarity measures (non-negativity, symmetry, boundedness, non-degeneracy, positive monotonicity, and extreme conflict). Finally, the proposed measure is compared and analyzed with mainstream similarity measures through multiple representative numerical cases and application cases in specialized fields such as fault diagnosis and target recognition. The experimental results validate the superiority of the proposed measure in terms of measurement accuracy.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117782"},"PeriodicalIF":5.6,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145897334","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}

{"title":"Weighted Hausdorff content and fractional maximal operators on self-similar sets","authors":"Jinjun Li,&nbsp;Fusheng Xiao","doi":"10.1016/j.chaos.2026.117861","DOIUrl":"10.1016/j.chaos.2026.117861","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Let &lt;span&gt;&lt;math&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; be a nontrivial self-similar set satisfying the strong separation condition with Hausdorff dimension &lt;span&gt;&lt;math&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; and let &lt;span&gt;&lt;math&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; be a self-similar measure on &lt;span&gt;&lt;math&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;. We introduce the weighted Hausdorff content &lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt;, the fractional maximal operator &lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt; and the weighted Choquet–Lorentz space &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; on &lt;span&gt;&lt;math&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;. Let &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;δ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;. For &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; we prove that the fractional maximal operator is bounded from &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; to &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;δ&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;. A weak-type estimate is also established at the critical exponent &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; for &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mfrac&gt;&lt;","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117861"},"PeriodicalIF":5.6,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145897477","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}

{"title":"Self-sustaining chaotic characteristics of liquid crystal elastomer pendulum under different linear temperature fields","authors":"Peibao Xu ,&nbsp;Jianhao Zhang ,&nbsp;Kuan Zhou ,&nbsp;Minghao Wang ,&nbsp;Wenfeng Hu","doi":"10.1016/j.chaos.2025.117812","DOIUrl":"10.1016/j.chaos.2025.117812","url":null,"abstract":"<div><div>Self-sustaining chaotic motion systems based on active materials have broad application prospects in fields such as energy harvesting, artificial hearts and medical devices. This paper presents a self-sustaining pendulum system composed of a liquid crystal elastomer fiber and a mass sphere, which exhibits different self-sustaining motion laws under different linear temperature fields. By establishing nonlinear dynamic models of the system, the numerical simulations reveal that under concentric circular linear temperature field, the pendulum can exhibit three self-sustaining motion modes: periodic vibration, periodic swing and chaotic swing. In contrast, only periodic vibration and periodic swing occur under planar and non-concentric linear temperature fields. The research reveals the mechanism of the self-sustaining motion and explains the reasons why different linear temperature fields exhibit different motion laws. This system achieves self-sustaining motion by using the contracting work of liquid crystal elastic fiber to compensate for energy dissipation. And a key distinction is that self-sustaining chaos arises in the pendulum system with position-independent driving, but is absent when the driving is position-dependent. This research achievement not only deepens the understanding of the self-sustaining motion of the pendulum, but also provides new ideas for the development of chaotic robots.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117812"},"PeriodicalIF":5.6,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145881939","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}

{"title":"Moderate intervention paradox in threshold-intensity regulated rock–paper–scissors competition systems","authors":"Yikang Lu ,&nbsp;Wenhao She ,&nbsp;Ryoo Kyung Yang ,&nbsp;Jie Jin ,&nbsp;Yuanni Yang ,&nbsp;Junpyo Park","doi":"10.1016/j.chaos.2025.117855","DOIUrl":"10.1016/j.chaos.2025.117855","url":null,"abstract":"<div><div>The cyclic competition governed by the rock–paper–scissors (RPS) game plays a crucial role in maintaining biodiversity and ecological stability in ecosystems. As an ecological management tool, human intervention often regulates population density to prevent species extinction or overpopulation. However, the synergistic effects of intervention thresholds and intensities on the stability of cyclic competition systems have not been sufficiently studied. In this paper, we extend the classical RPS dynamical framework by introducing a threshold-intensity-based intervention mechanism targeting a single species and construct a three-type nonlinear dynamical model. We systematically analyze the resulting dynamic behavior through linear stability analysis and numerical simulations at the mean-field level. As a result, we find the existence of four types of equilibria, demonstrating that only two- and three-species coexistence can achieve asymptotic stability within specific parameter ranges. While increasing intervention intensity can promote multi-species coexistence, excessive intervention intensity in environments with high competition-reproductive rates can lead to the dominance of a single species. This study reveals the “paradox of moderate intervention.” Interventions can prevent the extinction of target species, but two-way regulation can limit density growth, potentially weakening long-term competitive advantage. Our study provides a theoretical basis for quantifying the relationship between the threshold and intensity of ecological interventions and guides for designing intervention strategies that balance conservation benefits and management costs.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117855"},"PeriodicalIF":5.6,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882009","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}

{"title":"Controlling instabilities, bifurcations and chaos in a thermo-nanofluid porous layer","authors":"Abir Baidya,&nbsp;G.C. Layek","doi":"10.1016/j.chaos.2025.117859","DOIUrl":"10.1016/j.chaos.2025.117859","url":null,"abstract":"<div><div>This study reports controlling the onset of thermal convection and bifurcations of a horizontal nanofluid layer embedded in an isotropic porous medium under gravity subject to heating from below. The inclusion of nanoparticles with clear fluid is considered to maintain a single-phase nanofluid model. First, a linear stability analysis is performed through normal modes and obtain critical Rayleigh number of base fluid, which depends on the physical properties of the materials in the layer and its value increases with increasing the volumes of nanofragments. The principle of exchange of stability holds for the present model. Adopting low-order Galerkin approximations for velocity and temperature fields, we obtain a three dimensional nonlinear system. The linear stability and bifurcations are analyzed. Studies discourse that stationary convection emerges through supercritical pitchfork bifurcation, whereas oscillatory convection takes place via supercritical Hopf bifurcation. The critical value for Hopf bifurcation is non-monotonic with respect to porous medium characteristics. Also, there appears homoclinic bifurcation before Hopf bifurcation. The model exhibits basically two transitional routes to chaos, viz., (i) homoclinic explosion, and (ii) supercritical Hopf bifurcation. The enhancement of linear and weakly nonlinear stability thresholds are obtained. Further, chaotic motion is suppressed by increasing values of nanoparticles volume fractions. The convective mode is suppressed while the conductive mode of heat transfer strengthens resulting in the enhancement of overall heat transfer. In essence, nanofragments serve as passive stabilizer in the system and offer a powerful strategy for mitigating chaos and enhancing stability in heat driven engineering devices.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117859"},"PeriodicalIF":5.6,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894393","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}

{"title":"Self-similarity of continental-scale Twitter communication networks promotes synchronous outbreaks of information spreading","authors":"Xiaowen Hu ,&nbsp;Youhao Zhuo ,&nbsp;Jiao Wu ,&nbsp;Zhengling Wang ,&nbsp;Kesheng Xu ,&nbsp;Muhua Zheng","doi":"10.1016/j.chaos.2025.117856","DOIUrl":"10.1016/j.chaos.2025.117856","url":null,"abstract":"<div><div>Understanding how information spreads across regions to trigger large-scale outbreaks remains a key challenge, particularly regarding the influence of regional network structures on phase transitions. In this study, we analyze global Twitter communication networks and reveal clear statistical self-similarity across continents. We show that such self-similar structures facilitate synchronous outbreaks characterized by a single transition, whereas double continuous transitions arise only under extremely sparse intercontinental connectivity. To reproduce these patterns, we introduce a coupled hyperbolic geometric model, <span><math><msup><mrow><mi>S</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span>–<span><math><msup><mrow><mi>S</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span>, that captures both the self-similarity and spreading dynamics observed in empirical data. We further demonstrate that breaking self-similarity in the degree distribution promotes the emergence of double transitions. An edge-based compartmental theory accurately predicts all simulation results. These findings suggest a unified framework linking network geometry, self-similarity, and the mechanisms underlying secondary outbreaks in real-world information diffusion.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117856"},"PeriodicalIF":5.6,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145881942","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}

{"title":"Multi-operational mode-locked fiber laser enabled by SMS filtering and nonlinear polarization rotation","authors":"Yu-bin Zhang ,&nbsp;Hui-jing Du ,&nbsp;Yu-Can Wang ,&nbsp;Chun-Hang Ge ,&nbsp;Ling Qin ,&nbsp;Jia-Xin Zhang ,&nbsp;Zian Cheak Tiu ,&nbsp;Xing-Wei Li ,&nbsp;Shu-Guang Li ,&nbsp;Jian-She Li","doi":"10.1016/j.chaos.2025.117828","DOIUrl":"10.1016/j.chaos.2025.117828","url":null,"abstract":"<div><div>This work presents a switchable and tunable dual-wavelength mode-locked fiber laser based that integrates a single-mode–multi-mode–single-mode (SMS) filter structure with nonlinear polarization rotation (NPR). The SMS structure serves as the primary the main spectral filtering mechanism, while the NPR effect within the resonator cavity enables switching between dual-wavelength and single-wavelength operation under standard conditions. Furthermore, by adjusting the intracavity birefringence using a multimode fiber polarization controller (MMF-PC), the laser output exhibits three distinct tuning behaviors. Specifically, the single-wavelength bandwidth can be tuned by up to 13.84 nm, the dual-wavelength spacing can be adjusted by 6.78 nm, and the left wavelength can be independently tuned by 3.13 nm while the right wavelength remains fixed. The proposed laser demonstrates excellent flexibility and operational stability, underscoring its strong potential for applications in biomedical photonics, precision measurement, and industrial processing.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117828"},"PeriodicalIF":5.6,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145881938","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}

{"title":"Community-level contagion among diverse financial assets","authors":"An Pham Ngoc Nguyen,&nbsp;Marija Bezbradica,&nbsp;Martin Crane","doi":"10.1016/j.chaos.2025.117858","DOIUrl":"10.1016/j.chaos.2025.117858","url":null,"abstract":"<div><div>As global financial markets become increasingly interconnected, financial contagion has developed into a major influencer of asset price dynamics. Motivated by this context, our study explores financial contagion both within and between asset communities. We contribute to the literature by examining the contagion phenomenon at the community level rather than among individual assets. Our experiments rely on high-frequency data comprising cryptocurrencies, stocks and US ETFs over the 4-year period from April 2019 to May 2023. Using the Louvain community detection algorithm, Vector Autoregression contagion detection model and Tracy–Widom random matrix theory for noise removal from financial assets, we present three main findings. Firstly, while the magnitude of contagion remains relatively stable over time, contagion density (the percentage of asset pairs exhibiting contagion within a financial system) increases. This suggests that market uncertainty is better characterized by the transmission of shocks more broadly than by the strength of any single spillover. Secondly, there is no significant difference between intra- and inter-community contagion, indicating that contagion is a system-wide phenomenon rather than being confined to specific asset groups. Lastly, certain communities themselves, especially those dominated by Information Technology assets, tend to act as major contagion transmitters in the financial network over the examined period, spreading shocks with high densities to many other communities. Our findings suggest that traditional risk management strategies such as portfolio diversification through investing in low-correlated assets or different types of investment vehicle might be insufficient due to widespread contagion.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"205 ","pages":"Article 117858"},"PeriodicalIF":5.6,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882007","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}