数学最新文献

{"title":"Corrigendum and addendum to “Transitive permutation groups where nontrivial elements have at most two fixed points” [J. Pure Appl. Algebra 219(4) (2015) 729–759]","authors":"Paula Hähndel,&nbsp;Rebecca Waldecker","doi":"10.1016/j.jpaa.2025.108006","DOIUrl":"10.1016/j.jpaa.2025.108006","url":null,"abstract":"<div><div>This article revisits earlier work by the second author together with Kay Magaard. We correct several little results and we briefly discuss why, fortunately, the errors hardly affect our main theorems and in particular do not affect the classification of simple groups that act with fixity 2.</div></div>","PeriodicalId":54770,"journal":{"name":"Journal of Pure and Applied Algebra","volume":"229 8","pages":"Article 108006"},"PeriodicalIF":0.7,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144167252","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}

{"title":"Cyclic branched covers of Seifert links and properties related to the \u0000 \u0000 \u0000 A\u0000 D\u0000 E\u0000 \u0000 $ADE$\u0000 link conjecture","authors":"Steven Boyer,&nbsp;Cameron McA. Gordon,&nbsp;Ying Hu","doi":"10.1112/jlms.70178","DOIUrl":"https://doi.org/10.1112/jlms.70178","url":null,"abstract":"<p>In this article, we show that all cyclic branched covers of a Seifert link have left-orderable fundamental groups, and therefore admit co-oriented taut foliations and are not <span></span><math>\u0000 <semantics>\u0000 <mi>L</mi>\u0000 <annotation>$L$</annotation>\u0000 </semantics></math>-spaces, if and only if it is not an <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>A</mi>\u0000 <mi>D</mi>\u0000 <mi>E</mi>\u0000 </mrow>\u0000 <annotation>$ADE$</annotation>\u0000 </semantics></math> link up to orientation. This leads to a proof of the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>A</mi>\u0000 <mi>D</mi>\u0000 <mi>E</mi>\u0000 </mrow>\u0000 <annotation>$ADE$</annotation>\u0000 </semantics></math> link conjecture for Seifert links. When <span></span><math>\u0000 <semantics>\u0000 <mi>L</mi>\u0000 <annotation>$L$</annotation>\u0000 </semantics></math> is an <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>A</mi>\u0000 <mi>D</mi>\u0000 <mi>E</mi>\u0000 </mrow>\u0000 <annotation>$ADE$</annotation>\u0000 </semantics></math> link up to orientation, we determine which of its canonical <span></span><math>\u0000 <semantics>\u0000 <mi>n</mi>\u0000 <annotation>$n$</annotation>\u0000 </semantics></math>-fold cyclic branched covers <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>Σ</mi>\u0000 <mi>n</mi>\u0000 </msub>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mi>L</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation>$Sigma _n(L)$</annotation>\u0000 </semantics></math> have nonleft-orderable fundamental groups. In addition, we give a topological proof of Ishikawa's classification of strongly quasi-positive Seifert links and we determine the Seifert links that are definite, resp., have genus zero, resp. have genus equal to its smooth 4-ball genus, among others. In the last section, we provide a comprehensive survey of the current knowledge and results concerning the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>A</mi>\u0000 <mi>D</mi>\u0000 <mi>E</mi>\u0000 </mrow>\u0000 <annotation>$ADE$</annotation>\u0000 </semantics></math> link conjecture.</p>","PeriodicalId":49989,"journal":{"name":"Journal of the London Mathematical Society-Second Series","volume":"111 6","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1112/jlms.70178","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172003","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}

{"title":"Geometric nonlinear dynamics of a quasi-zero stiffness isolator integrated with an energy harvester: Monostable, perfect zero-linear stiffness, and bistable oscillation modes","authors":"Nasser A. Saeed ,&nbsp;Y.Y. Ellabban ,&nbsp;Lei Hou ,&nbsp;Shun Zhong ,&nbsp;Faisal Z. Duraihem","doi":"10.1016/j.chaos.2025.116633","DOIUrl":"10.1016/j.chaos.2025.116633","url":null,"abstract":"<div><div>Achieving effective vibration isolation across a broad frequency range while simultaneously harvesting energy from vibrations remains a key challenge in engineering systems. This study examines the nonlinear dynamics and vibration isolation performance of an oblique-type spring quasi-zero stiffness (QZS) isolator integrated with a piezoelectric energy harvester. The coupled system is modeled as a strongly nonlinear oscillator linked to a first-order differential equation governing the harvester's response. The QZS isolator's behavior is characterized by two geometric nonlinearity parameters, the stiffness ratio of oblique to vertical springs (<span><math><mi>ρ</mi></math></span>) and the ratio of the oblique spring's maximum horizontal compression to its free length (<span><math><mi>λ</mi></math></span>). Closed-form expressions for <span><math><mi>ρ</mi></math></span> and <span><math><mi>λ</mi></math></span> are derived to determine the conditions for monostable, bistable, and perfect zero-linear stiffness operation. The system's response is analyzed using the harmonic balance method, with bifurcation diagrams illustrating oscillation amplitudes, harvested voltage, and displacement transmissibility under different excitation conditions. Key findings indicate that for <span><math><mi>ρ</mi><mo>&lt;</mo><mi>λ</mi><mo>/</mo><mfenced><mrow><mn>2</mn><mo>−</mo><mn>2</mn><mi>λ</mi></mrow></mfenced></math></span>, the system functions as a monostable QZS isolator, where reducing <span><math><mi>λ</mi></math></span> and/or increasing <span><math><mi>ρ</mi></math></span> suppresses resonant peaks, creating a semi-full-band isolator. When <span><math><mi>ρ</mi><mo>=</mo><mi>λ</mi><mo>/</mo><mfenced><mrow><mn>2</mn><mo>−</mo><mn>2</mn><mi>λ</mi></mrow></mfenced></math></span>, the system achieves full-band vibration isolation with perfect zero-linear stiffness, enhanced by high pre-compression of the oblique springs. For <span><math><mi>ρ</mi><mo>&gt;</mo><mi>λ</mi><mo>/</mo><mfenced><mrow><mn>2</mn><mo>−</mo><mn>2</mn><mi>λ</mi></mrow></mfenced></math></span>, the system transitions to a bistable regime, improving energy harvesting but reducing isolation efficiency. Additionally, the piezoelectric harvester not only facilitates energy conversion but also introduces active damping, effectively mitigating resonant peaks and stabilizing the system under strong base excitations while minimally affecting high-frequency displacement transmissibility. This work provides a comprehensive understanding of the oscillation modes in oblique-type QZS systems and offers design insights for optimizing geometric parameters to achieve full-band or semi-full-band isolation and efficient energy harvesting.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"199 ","pages":"Article 116633"},"PeriodicalIF":5.3,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144166080","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":"On strong odd colorings of graphs","authors":"Yair Caro ,&nbsp;Mirko Petruševski ,&nbsp;Riste Škrekovski ,&nbsp;Zsolt Tuza","doi":"10.1016/j.disc.2025.114601","DOIUrl":"10.1016/j.disc.2025.114601","url":null,"abstract":"<div><div>A strong odd coloring of a simple graph <em>G</em> is a proper coloring of the vertices of <em>G</em> such that for every vertex <em>v</em> and every color <em>c</em>, either <em>c</em> is used an odd number of times in the open neighborhood <span><math><msub><mrow><mi>N</mi></mrow><mrow><mi>G</mi></mrow></msub><mo>(</mo><mi>v</mi><mo>)</mo></math></span> or no neighbor of <em>v</em> is colored by <em>c</em>. The smallest integer <em>k</em> for which <em>G</em> admits a strong odd coloring with <em>k</em> colors is the strong odd chromatic number, <span><math><msub><mrow><mi>χ</mi></mrow><mrow><mi>so</mi></mrow></msub><mo>(</mo><mi>G</mi><mo>)</mo></math></span>. These coloring notion and graph parameter were recently defined in Kwon and Park (<span><span>arXiv:2401.11653</span><svg><path></path></svg></span>). We answer a question raised by the originators concerning the existence of a constant bound for the strong odd chromatic number of all planar graphs. We also consider strong odd colorings of trees, unicyclic graphs, claw-free graphs, and graph products.</div></div>","PeriodicalId":50572,"journal":{"name":"Discrete Mathematics","volume":"348 11","pages":"Article 114601"},"PeriodicalIF":0.7,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170355","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}

{"title":"Effect of malicious cyber-attack on jamming transition in a multi-phase mixed flow model under regular vehicles and connected vehicles environment","authors":"Yi Tang ,&nbsp;Cong Zhai ,&nbsp;Yingping Xiao ,&nbsp;Min Zhai ,&nbsp;Jiyong Zhang","doi":"10.1016/j.chaos.2025.116665","DOIUrl":"10.1016/j.chaos.2025.116665","url":null,"abstract":"<div><div>With the promotion of policies and technological progress, accelerate the advancement of Internet of Vehicles (IOVs) and refine it considerably, and then the real-time communication of vehicle-vehicle, vehicle-infrastructure and vehicle cloud will be realized, which will provide more abundant data for connected vehicles (CVs); however, the large-scale popularization of the vehicle was a drawn-out procedure, and regular vehicles (RVs) and connected vehicles will share road infrastructure within this duration. Aiming at the significant distinctions in exogenous information acquisition mode between the two types of vehicles, and considering that the latter is vulnerable to cyber-attacks from hackers when it plays the advantage of information sharing in an open workshop communication environment. Motivation by this, we extended the optimal velocity car-following model and provided an original mixed-flow model accounting for the malicious cyber-attack effect, moreover, introducing a multi-phase optimal velocity function to describe the discontinuous acceleration phenomenon in real traffic. In the linear stability analysis part, we employ the reductive perturbation approaches to figure out the stability requirement for the new model, which reveals that the permeability of CVs and the intensity of cyber-attacks have a substantial influence on the traffic dynamics, and the number of phases of transition stages highly dependent on the count of the turning points in the optimal velocity function; subsequently, in the nonlinear analysis part, the modified Korteweg-de Vries (mKdV) equation is developed to illustrate the emerge and spatiotemporal progression of traffic jams when stability criteria is not achieved. At last, the above theoretical arguments are supported by the numerical simulation results.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"199 ","pages":"Article 116665"},"PeriodicalIF":5.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144167215","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 memristive neuron with double capacitive variables coupled by Josephson junction","authors":"Binchi Wang ,&nbsp;Guodong Ren ,&nbsp;Jun Ma ,&nbsp;Yitong Guo","doi":"10.1016/j.chaos.2025.116630","DOIUrl":"10.1016/j.chaos.2025.116630","url":null,"abstract":"<div><div>Continuous firing patterns in biological neurons result from time-varying electromagnetic field accompanied by energy exchange between magnetic field and electric field in the cell, which the intracellular ions are diffused and membrane channels are open for ions propagation across the outer and inner cell membranes. Incorporation of memristive terms of the neuron models can describe the effect of electromagnetic induction and even the regulation from external applied physical field. During circuit approach and implement for a neural circuit, capacitors are used to mimic the capacitive properties of the cell membrane, while inductors, nonlinear resistor and constant voltage source are effective to mimic the physical properties of ion channels. This paper proposed a neural circuit composed of two capacitors via Josephson junction connection, and the paralleled branch circuits are connected by using an inductor and a memristor. The absence using of both linear and nonlinear resistors reduces consumption of Joule heat. Energy function for the two kinds of memristive neurons are obtained and proofed, stochastic/coherence resonance is induced under noisy excitation at moderate noise intensity. Stability and bifurcation analysis clarified the main dynamical and physical property of the suggested neural circuits and their equivalent dimensionless models. Finally, an adaptive growth law is suggested to control the membrane parameter and mode transition between firing patterns is discussed in detail. That is, the neural circuit coupled with memristor and Josephson junction is effective to describe the electrical property and dynamical characteristic even without using any resistive components.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116630"},"PeriodicalIF":5.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168290","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":"On a class of exact solutions of the Ishimori equation","authors":"Rustem N. Garifullin,&nbsp;Ismagil T. Habibullin","doi":"10.1016/j.physd.2025.134746","DOIUrl":"10.1016/j.physd.2025.134746","url":null,"abstract":"<div><div>In this paper, a class of particular solutions of the Ishimori equation is found. This equation is known as the spatially two-dimensional version of the Heisenberg equation, which has important applications in the theory of ferromagnets. It is shown that the two-dimensional Toda-type lattice found earlier by Ferapontov, Shabat and Yamilov is a dressing chain for this equation. Using the integrable reductions of the dressing chain, the authors found an essentially new class of solutions to the Ishimori equation.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"480 ","pages":"Article 134746"},"PeriodicalIF":2.7,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144185223","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}

{"title":"Oscillation theory for linear evolution processes","authors":"M.Ap. Silva ,&nbsp;E.M. Bonotto ,&nbsp;M. Federson","doi":"10.1016/j.jde.2025.113464","DOIUrl":"10.1016/j.jde.2025.113464","url":null,"abstract":"<div><div>We introduce the theory of pullback oscillation for linear evolution processes. Necessary and sufficient conditions are presented to obtain pullback oscillation via geometric interpretation of the closed conic hull. Using the theory of generalized ODEs, we apply the main results to a class of abstract ordinary differential equations, as well as to Volterra-Stieltjes-type integral equations.</div></div>","PeriodicalId":15623,"journal":{"name":"Journal of Differential Equations","volume":"440 ","pages":"Article 113464"},"PeriodicalIF":2.4,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169295","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}

{"title":"Structural identifiability of linear-in-parameter parabolic PDEs through auxiliary elliptic operators.","authors":"Yurij Salmaniw, Alexander P Browning","doi":"10.1007/s00285-025-02225-w","DOIUrl":"https://doi.org/10.1007/s00285-025-02225-w","url":null,"abstract":"<p><p>Parameter identifiability is often requisite to the effective application of mathematical models in the interpretation of biological data, however theory applicable to the study of partial differential equations remains limited. We present a new approach to structural identifiability analysis of fully observed parabolic equations that are linear in their parameters. Our approach frames identifiability as an existence and uniqueness problem in a closely related elliptic equation and draws, for homogeneous equations, on the well-known Fredholm alternative to establish unconditional identifiability, and cases where specific choices of initial and boundary conditions lead to non-identifiability. While in some sense pathological, we demonstrate that this loss of structural identifiability has ramifications for practical identifiability; important particularly for spatial problems, where the initial condition is often limited by experimental constraints. For cases with nonlinear reaction terms, uniqueness of solutions to the auxiliary elliptic equation corresponds to identifiability, often leading to unconditional global identifiability under mild assumptions. We present analysis for a suite of simple scalar models with various boundary conditions that include linear (exponential) and nonlinear (logistic) source terms, and a special case of a two-species cell motility model. We conclude by discussing how this new perspective enables well-developed analysis tools to advance the developing theory underlying structural identifiability of partial differential equations.</p>","PeriodicalId":50148,"journal":{"name":"Journal of Mathematical Biology","volume":"91 1","pages":"4"},"PeriodicalIF":2.2,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144175700","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}

{"title":"Steady compressible 3D Euler flows in toroidal volumes without continuous Euclidean isometries","authors":"Naoki Sato ,&nbsp;Michio Yamada","doi":"10.1016/j.physd.2025.134741","DOIUrl":"10.1016/j.physd.2025.134741","url":null,"abstract":"<div><div>We demonstrate the existence of smooth three-dimensional vector fields where the cross product between the vector field and its curl is balanced by the gradient of a smooth function, with toroidal level sets that are not invariant under continuous Euclidean isometries. This finding indicates the existence of steady compressible Euler flows, either influenced by an external potential energy or maintained by a density source in the continuity equation, that are foliated by asymmetric nested toroidal surfaces. Our analysis suggests that the primary obstacle in resolving Grad’s conjecture regarding the existence of nontrivial magnetohydrodynamic equilibria arises from the incompressibility constraint imposed on the magnetic field.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"480 ","pages":"Article 134741"},"PeriodicalIF":2.7,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169732","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}