Physica D: Nonlinear Phenomena最新文献_第7页

Revisiting amplitude death in the presence of diffusion asymmetry 在扩散不对称的情况下重新审视振幅死亡

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-29 DOI: 10.1016/j.physd.2025.134740

Garima Saxena

引用次数: 0

On the local structure of degenerate Teixeira singularities in 3D Filippov systems 三维Filippov系统退化Teixeira奇点的局部结构

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-29 DOI: 10.1016/j.physd.2025.134735

Oscar A.R. Cespedes , Rony Cristiano , Otávio M.L. Gomide

{"title":"On the local structure of degenerate Teixeira singularities in 3D Filippov systems","authors":"Oscar A.R. Cespedes , Rony Cristiano , Otávio M.L. Gomide","doi":"10.1016/j.physd.2025.134735","DOIUrl":"10.1016/j.physd.2025.134735","url":null,"abstract":"<div><div>The main goal of this paper is to emphasize the richness of the dynamics emanating from degeneracies at the so-called T-singularity in <span><math><mrow><mn>3</mn><mi>D</mi></mrow></math></span> Filippov systems. More specifically, we characterize the local sliding and crossing dynamics around an invisible two-fold singularity in <span><math><mrow><mn>3</mn><mi>D</mi></mrow></math></span> Filippov systems which presents a degeneracy arising from the contact between the tangency fold curves of a system with the switching manifold. In particular, we prove that, when the contact between such curves is 2 or 3 at this point, then it presents a nonsmooth diabolo emanating from it which has one branch or two branches, respectively.</div><div>We also analyze global bifurcations of a family of Filippov systems which presents an invisible two-fold singularity having a cubic contact between the fold curves and we show that there is an invariant surface foliated by crossing heteroclinic orbits between <span><math><mi>T</mi></math></span>-singularities bifurcating from this degenerate singularity. Finally, we show that such kind of scenario appears naturally in applied models of switched electronic circuits and this singularity is realized in an specific model.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"480 ","pages":"Article 134735"},"PeriodicalIF":2.7,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144185097","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

Shielding of breathers for the focusing nonlinear Schrödinger equation 聚焦非线性Schrödinger方程的呼吸器屏蔽

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-29 DOI: 10.1016/j.physd.2025.134744

Gregorio Falqui , Tamara Grava , Christian Puntini

引用次数: 0

Frequency-domain computation of Lyapunov-Perron transformation with detection of quasi-periodic solution bifurcation 拟周期解分岔检测Lyapunov-Perron变换的频域计算

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-29 DOI: 10.1016/j.physd.2025.134765

Yanmao Chen, Jike Liu

{"title":"Frequency-domain computation of Lyapunov-Perron transformation with detection of quasi-periodic solution bifurcation","authors":"Yanmao Chen, Jike Liu","doi":"10.1016/j.physd.2025.134765","DOIUrl":"10.1016/j.physd.2025.134765","url":null,"abstract":"<div><div>Lyapunov-Perron (LP) transformation is well-known as an indispensible technique to reduce a linear quasi-periodic (QP) system, under certain conditions, into a time-invariant one, which we call the reduced system. The reducibility of QP system received a lot of qualitative studies, however quite few research focused on the quantification of the LP transformation itself. The major obstacle probably consists in the calculation of a QP matrix describing the transformation. In this study we will propose a semi-analytical approach, based on frequency-domain analysis, to determine the LP transformation precisely and efficiently. Our approach is divided into two steps. Firstly a constant matrix is determined to represent the reduced system, utilizing the circularly distributed multipliers of the QP system provided by a frequency-domain approach established recently by the authors. With the constant matrix, a linear and solvable QP system governing the transformation matrix is deduced and solved via harmonic balancing, in which the harmonic coefficients are provided by linear algebraic equations. Numerical examples show the semi-analytical results are very accurate for both the constant and the QP matrix, representing the reduced system and the LP transformation, respectively.</div><div>As an application, the proposed approach provides us with a convenient way to detect the bifurcation types of QP responses. For instance, the harmonic components of the QP matrix are analyzed for distinguishing saddle-node and symmetry-breaking bifurcations. For a special example where the QP system cannot be reduced via the routine LP transformation, interestingly, it turns out the system reduction can still be realized via an extended transformation. The harmonic components of the QP matrix in the extended transformation can also identify period-doubling bifurcation. Lastly the proposed approach is shown to be capable of detecting QP Hopf bifurcation, exemplified by a van der Pol-Rossler coupled system.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"481 ","pages":"Article 134765"},"PeriodicalIF":2.7,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144205396","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

Four-equation model for unified prediction of turbulent mixing induced by interfacial instabilities 界面不稳定引起的湍流混合统一预测的四方程模型

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-28 DOI: 10.1016/j.physd.2025.134724

Rui-han Zhao , Han-song Xie , Meng-juan Xiao , Yu-hui Wang , You-sheng Zhang

{"title":"Four-equation model for unified prediction of turbulent mixing induced by interfacial instabilities","authors":"Rui-han Zhao , Han-song Xie , Meng-juan Xiao , Yu-hui Wang , You-sheng Zhang","doi":"10.1016/j.physd.2025.134724","DOIUrl":"10.1016/j.physd.2025.134724","url":null,"abstract":"<div><div>Turbulent mixing induced by interfacial instabilities are generally predicted using the Reynolds-averaged Navier–Stokes (RANS) model in practical applications. Among RANS models, the advanced Besnard–Harlow–Rauenzahn (BHR) series stand out due to its capacity to characterize the mixing state, which is quite important for reaction rate calculation in fusion engineering. However, the present limitation of this model is its inability to unified predict mixing growth rates and profiles across diverse density ratios or types of turbulent mixing scenarios. To overcome these limitations, we extend the methodology in determining turbulence model coefficients to the four-equation framework. The extension concerns a refined four-equation model, particularly in modifying the dissipation term associated with the density-specific volume covariance, thereby greatly improving the model’s performance at high density ratios. Further, new self-similar profiles for various physical quantities are introduced by considering more realistic evolution. This enhancement is shown to yield more plausible predictions. Finally, leveraging the unique traits of the four-equation model, we utilize an ansatz of self-similarity to derive consistent model coefficients ensemble tailored to different turbulent mixing scenarios. With these enhancements, this model realizes unified predictions of mixing width and profiles across classical turbulent mixings and complex mixings, agreeing well with high-fidelity numerical simulations and experimental measurements. Given the model’s descriptive prowess of mixing state characteristics pertinent to engineering challenges, it has significant potential in the precise prediction of fusion reaction rate and assessments of fusion performance.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"480 ","pages":"Article 134724"},"PeriodicalIF":2.7,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178727","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

Long-time dynamics of a parabolic-ODE SIS epidemic model with saturated incidence mechanism 具有饱和发病机制的抛物- ode SIS流行病模型的长时间动力学

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-28 DOI: 10.1016/j.physd.2025.134747

Rui Peng , Rachidi Salako , Yixiang Wu

{"title":"Long-time dynamics of a parabolic-ODE SIS epidemic model with saturated incidence mechanism","authors":"Rui Peng , Rachidi Salako , Yixiang Wu","doi":"10.1016/j.physd.2025.134747","DOIUrl":"10.1016/j.physd.2025.134747","url":null,"abstract":"<div><div>In this paper, we investigate a parabolic-ODE SIS epidemic model with no-flux boundary conditions in a heterogeneous environment. The model incorporates a saturated infection mechanism <span><math><mrow><mi>S</mi><mi>I</mi><mo>/</mo><mrow><mo>(</mo><mi>m</mi><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>+</mo><mi>S</mi><mo>+</mo><mi>I</mi><mo>)</mo></mrow></mrow></math></span> with <span><math><mrow><mi>m</mi><mo>≥</mo><mo>,</mo><mspace></mspace><mo>⁄</mo><mo>≡</mo><mn>0</mn></mrow></math></span>. This study is motivated by disease control strategies, such as quarantine and lockdown, that limit population movement. We examine two scenarios: one where the movement of the susceptible population is restricted, and the other where the movement of the infected population is neglected. We establish the long-term dynamics of the solutions in each scenario. Compared to previous studies that assume the absence of a saturated incidence function (i.e., <span><math><mrow><mi>m</mi><mo>≡</mo><mn>0</mn></mrow></math></span>), our findings highlight the novel and significant interplay between total population size, transmission risk level, and the saturated incidence function in influencing disease persistence, extinction, and spatial distribution. Numerical simulations are performed to validate the theoretical results, and the implications of the results are discussed in the context of disease control and eradication strategies.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"481 ","pages":"Article 134747"},"PeriodicalIF":2.7,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144205649","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

Assessment of anti-jamming capabilities in infrared-guided missile systems 红外制导导弹系统抗干扰能力评估

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-28 DOI: 10.1016/j.physd.2025.134737

Xinyan Li , Sange Li , Zhaoxing Gao

{"title":"Assessment of anti-jamming capabilities in infrared-guided missile systems","authors":"Xinyan Li , Sange Li , Zhaoxing Gao","doi":"10.1016/j.physd.2025.134737","DOIUrl":"10.1016/j.physd.2025.134737","url":null,"abstract":"<div><div>Missiles possess immense destructive power and play a decisive role in determining military strength in conflicts. Existing research predominantly focuses on the guidance system level, evaluating missile anti-jamming performance based on the overall missile system and often using anti-jamming probability as the sole metric. However, this approach lacks systematic investigation into the anti-jamming process. To address this gap, this paper establishes a multi-level evaluation system for infrared guided missile, analyzing the missile overall system, guidance system, seeker, and external environment. By employing the Fuzzy Analytic Hierarchy Process (Fuzzy AHP), weight coefficients for each component are calculated using a fuzzy judgment matrix, enabling a comprehensive evaluation and the construction of a multi-level evaluation index system. Simulation experiments were conducted to validate the model’s effectiveness. Using the Latin Hypercube Sampling (LHS) algorithm, approximately 1,000 scenarios capturing the essential characteristics of missile anti-jamming were generated, reducing computational time by around 80% while maintaining accuracy. Experimental results demonstrated a recognition probability exceeding 85% and average miss distances within acceptable limits. Both static and dynamic validation confirmed the model’s robustness, proving its ability to accurately predict missile anti-jamming performance under various conditions. This study provides a solid foundation for future research and improvements in missile anti-jamming systems.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"481 ","pages":"Article 134737"},"PeriodicalIF":2.7,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194494","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

Topological horseshoe and uniform hyperbolicity of the symplectic coupled Hénon map 辛耦合hsamnon映射的拓扑马蹄形和一致双曲性

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-26 DOI: 10.1016/j.physd.2025.134722

Keisuke Fujioka , Ryota Kogawa , Jizhou Li , Akira Shudo

引用次数: 0

Flow-through problem for a Jeffreys type viscoelastic fluid 杰弗里斯型粘弹性流体的流动问题

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-25 DOI: 10.1016/j.physd.2025.134726

Evgenii S. Baranovskii

引用次数: 0

Group-convolutional extended dynamic mode decomposition 群卷积扩展动态模态分解

IF 2.7 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-05-24 DOI: 10.1016/j.physd.2025.134725

Hans Harder , Feliks Nüske , Friedrich M. Philipp , Manuel Schaller , Karl Worthmann , Sebastian Peitz

{"title":"Group-convolutional extended dynamic mode decomposition","authors":"Hans Harder , Feliks Nüske , Friedrich M. Philipp , Manuel Schaller , Karl Worthmann , Sebastian Peitz","doi":"10.1016/j.physd.2025.134725","DOIUrl":"10.1016/j.physd.2025.134725","url":null,"abstract":"<div><div>This paper explores the integration of symmetries into the Koopman-operator framework for the analysis and efficient learning of equivariant dynamical systems using a group-convolutional approach. Approximating the Koopman operator by finite-dimensional surrogates, e.g., via extended dynamic mode decomposition (EDMD), is challenging for high-dimensional systems due to computational constraints. To tackle this problem with a particular focus on EDMD, we demonstrate – under suitable equivariance assumptions on the system and the observables – that the optimal EDMD matrix is equivariant. That is, its action on states can be described by group convolutions and the generalized Fourier transform. We show that this structural property has many advantages for equivariant systems, in particular, that it allows for data-efficient learning, fast predictions and fast eigenfunction approximations. We conduct numerical experiments on the Kuramoto–Sivashinsky equation and a <span><math><mi>λ</mi></math></span>-<span><math><mi>ω</mi></math></span> spiraling wave system, both nonlinear partial differential equations, providing evidence of the effectiveness of this approach, and highlighting its potential for broader applications in dynamical systems analysis.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"480 ","pages":"Article 134725"},"PeriodicalIF":2.7,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169786","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