Pub Date : 2026-01-03DOI: 10.1016/j.nonrwa.2025.104598
Fizay-Noah Lee
We consider the steady state Nernst-Planck system for multiple species with nonequilibrium boundary conditions, describing electrodiffusion of ions or charged particles. We show the existence and regularity of solutions and also establish a sufficient condition for uniqueness.
{"title":"Existence, uniqueness and regularity of nonequilibrium steady states in multispecies ion transport","authors":"Fizay-Noah Lee","doi":"10.1016/j.nonrwa.2025.104598","DOIUrl":"10.1016/j.nonrwa.2025.104598","url":null,"abstract":"<div><div>We consider the steady state Nernst-Planck system for multiple species with nonequilibrium boundary conditions, describing electrodiffusion of ions or charged particles. We show the existence and regularity of solutions and also establish a sufficient condition for uniqueness.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104598"},"PeriodicalIF":1.8,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885260","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}
Pub Date : 2025-12-30DOI: 10.1016/j.nonrwa.2025.104582
Shri Harine P, Ankit Kumar
Classical prey-predator models often assume that the predator’s handling time is constant. However, in real ecosystems, a predator’s handling time can vary due to several biotic and abiotic factors. Based on this, we modified the Holling Type II functional response by incorporating a nonlinear handling time function. Fear in prey can lead to notable population reductions, predominantly through decreased foraging and reproduction. Considering these essential factors, we developed a prey-predator model encompassing temporal dynamics, self-diffusion and cross-diffusion. For the temporal model, we investigated the non-negativity, boundedness, and stability conditions of the existing steady states. Furthermore, bifurcations such as Hopf, transcritical, and Bautin were observed with respect to parameters like the cost of fear and the maximal achievable handling time. Bistability behaviour was observed through the analysis involving these two parameters. Sensitivity analysis was conducted to understand the influence of parameters contributing to the coexistence of prey and predator populations. Stability conditions for both spatiotemporal models (with self and cross-diffusion) were established, highlighting the role of cross-diffusion coefficients in inducing Turing instability and pattern formation. Spatial patterns such as spots and vertically aligned chains were observed. An increase in the maximal achievable handling time was found to support prey occupation in high-density regions, promoting coexistence, whereas excessively high maximal handling time can lead to predator extinction.
{"title":"Modelling spatiotemporal prey-predator interactions incorporating fear effect and variable handling time","authors":"Shri Harine P, Ankit Kumar","doi":"10.1016/j.nonrwa.2025.104582","DOIUrl":"10.1016/j.nonrwa.2025.104582","url":null,"abstract":"<div><div>Classical prey-predator models often assume that the predator’s handling time is constant. However, in real ecosystems, a predator’s handling time can vary due to several biotic and abiotic factors. Based on this, we modified the Holling Type II functional response by incorporating a nonlinear handling time function. Fear in prey can lead to notable population reductions, predominantly through decreased foraging and reproduction. Considering these essential factors, we developed a prey-predator model encompassing temporal dynamics, self-diffusion and cross-diffusion. For the temporal model, we investigated the non-negativity, boundedness, and stability conditions of the existing steady states. Furthermore, bifurcations such as Hopf, transcritical, and Bautin were observed with respect to parameters like the cost of fear and the maximal achievable handling time. Bistability behaviour was observed through the analysis involving these two parameters. Sensitivity analysis was conducted to understand the influence of parameters contributing to the coexistence of prey and predator populations. Stability conditions for both spatiotemporal models (with self and cross-diffusion) were established, highlighting the role of cross-diffusion coefficients in inducing Turing instability and pattern formation. Spatial patterns such as spots and vertically aligned chains were observed. An increase in the maximal achievable handling time was found to support prey occupation in high-density regions, promoting coexistence, whereas excessively high maximal handling time can lead to predator extinction.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104582"},"PeriodicalIF":1.8,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885263","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}
Pub Date : 2025-12-30DOI: 10.1016/j.nonrwa.2025.104587
Samuel Carlos S. Ferreira , Bruno R. Freitas , João Carlos R. Medrado
We analyze a 3D discontinuous piecewise linear dynamical system, , with a plane Σ as its switching manifold, which contains two-fold intersection straight lines. The eigenvalues associated with DX and DY are composed of one real eigenvalue and a pair of complex conjugate eigenvalues. A canonical form is obtained using changes in variables and parameters. Two half-return Poincaré maps are generated from two closing equations derived from exponential matrices, leading to a displacement map Δ. Using the Weierstrass Preparation Theorem, we prove the existence of a subclass within this family that admits at least one large amplitude limit cycle. When the real part of the complex eigenvalues is non-zero, the restriction of Δ to space W, formed by the concatenation of bi-dimensional focal planes associated with the complex eigenvalues, can have up to three positive zeros on W ∩ Σ, corresponding to three large amplitude limit cycles. We provide examples with one, two, and three limit cycles.
{"title":"Limit cycles of 3D piecewise linear systems with concurrent tangent lines","authors":"Samuel Carlos S. Ferreira , Bruno R. Freitas , João Carlos R. Medrado","doi":"10.1016/j.nonrwa.2025.104587","DOIUrl":"10.1016/j.nonrwa.2025.104587","url":null,"abstract":"<div><div>We analyze a 3D discontinuous piecewise linear dynamical system, <span><math><mrow><mi>Z</mi><mo>=</mo><mrow><mo>(</mo><mi>X</mi><mo>,</mo><mi>Y</mi><mo>)</mo></mrow></mrow></math></span>, with a plane Σ as its switching manifold, which contains two-fold intersection straight lines. The eigenvalues associated with <em>DX</em> and <em>DY</em> are composed of one real eigenvalue and a pair of complex conjugate eigenvalues. A canonical form is obtained using changes in variables and parameters. Two half-return Poincaré maps are generated from two closing equations derived from exponential matrices, leading to a displacement map Δ. Using the Weierstrass Preparation Theorem, we prove the existence of a subclass within this family that admits at least one large amplitude limit cycle. When the real part of the complex eigenvalues is non-zero, the restriction of Δ to space <em>W</em>, formed by the concatenation of bi-dimensional focal planes associated with the complex eigenvalues, can have up to three positive zeros on <em>W</em> ∩ Σ, corresponding to three large amplitude limit cycles. We provide examples with one, two, and three limit cycles.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104587"},"PeriodicalIF":1.8,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885261","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}
Pub Date : 2025-12-27DOI: 10.1016/j.nonrwa.2025.104586
Chun-Bo Lian , Bin Ge , Qing-Hai Cao , Qing-Mei Zhou
In the present paper, we study the existence of a radial sign-changing solution to a class of quasilinear double phase problems in . Without assuming the usual strictly increasing condition on , we provide some sufficient conditions under which the above problems have at least one sign-changing radial ground states solution. We generalize the result of Liu and Dai [J. Math. Phys. 61(2020) 091508].
{"title":"Quasilinear double phase problem on the whole space","authors":"Chun-Bo Lian , Bin Ge , Qing-Hai Cao , Qing-Mei Zhou","doi":"10.1016/j.nonrwa.2025.104586","DOIUrl":"10.1016/j.nonrwa.2025.104586","url":null,"abstract":"<div><div>In the present paper, we study the existence of a radial sign-changing solution to a class of quasilinear double phase problems in <span><math><msup><mi>R</mi><mi>N</mi></msup></math></span>. Without assuming the usual strictly increasing condition on <span><math><mfrac><mrow><mi>f</mi><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo></mrow><msup><mrow><mo>|</mo><mi>t</mi><mo>|</mo></mrow><mrow><mi>q</mi><mo>−</mo><mn>1</mn></mrow></msup></mfrac></math></span>, we provide some sufficient conditions under which the above problems have at least one sign-changing radial ground states solution. We generalize the result of Liu and Dai [J. Math. Phys. 61(2020) 091508].</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104586"},"PeriodicalIF":1.8,"publicationDate":"2025-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885262","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}
Pub Date : 2025-12-25DOI: 10.1016/j.nonrwa.2025.104572
Guanghui Wang , Mingying Zhong
The pointwise estimates of the Green’s function for the incompressible Navier–Stokes–Maxwell system with Ohm’s law in 3D are given in this paper. It is shown that the Green’s function consists of the heat kernels, the diffusive waves at low-frequency, the hyperbolic waves at high-frequency with time decaying exponentially, and the singular short waves. In addition, we establish the pointwise estimate of the global solution to the nonlinear incompressible Navier–Stokes–Maxwell system with Ohm’s law based on the Green’s function. To solve the new problem that the nonlinear terms contain the nonlocal operators and which arise from the fluid-electromagnetic decomposition, we develop some new estimates of the nonlocal operators.
{"title":"The pointwise estimates for the incompressible Navier–Stokes–Maxwell system with Ohm’s law","authors":"Guanghui Wang , Mingying Zhong","doi":"10.1016/j.nonrwa.2025.104572","DOIUrl":"10.1016/j.nonrwa.2025.104572","url":null,"abstract":"<div><div>The pointwise estimates of the Green’s function for the incompressible Navier–Stokes–Maxwell system with Ohm’s law in 3D are given in this paper. It is shown that the Green’s function consists of the heat kernels, the diffusive waves at low-frequency, the hyperbolic waves at high-frequency with time decaying exponentially, and the singular short waves. In addition, we establish the pointwise estimate of the global solution to the nonlinear incompressible Navier–Stokes–Maxwell system with Ohm’s law based on the Green’s function. To solve the new problem that the nonlinear terms contain the nonlocal operators <span><math><mrow><mi>∇</mi><mrow><mrow><mi>d</mi></mrow><mi>i</mi><mi>v</mi></mrow><mstyle><mi>Δ</mi></mstyle><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> and <span><math><mrow><mi>∇</mi><mo>×</mo><mi>∇</mi><mo>×</mo><mstyle><mi>Δ</mi></mstyle><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> which arise from the fluid-electromagnetic decomposition, we develop some new estimates of the nonlocal operators.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104572"},"PeriodicalIF":1.8,"publicationDate":"2025-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841570","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}
Pub Date : 2025-12-24DOI: 10.1016/j.nonrwa.2025.104560
Liyan Pang , Xiao Zhang
In this paper, the long time behavior for a two-species Lotka-Volterra reaction-diffusion system with strong competition in a periodic medium is concerned. We prove that under the compactly supported initial values, the solutions of Cauchy problem converge to a pair of diverging pulsating fronts. Further, we obtain a sufficient condition for solutions to converge to 1 with two different speeds to the left and right. Due to the spatial heterogeneity, the pulsating fronts depend on its direction and any pair of rightward and leftward wave speeds be asymmetrical. Therefore, our analysis mainly depends on constructing appropriate super- and subsolutions and using the comparison principle and asymptotic behavior of bistable pulsating fronts.
{"title":"Long time behavior for a Lotka-Volterra competition diffusion system in periodic medium","authors":"Liyan Pang , Xiao Zhang","doi":"10.1016/j.nonrwa.2025.104560","DOIUrl":"10.1016/j.nonrwa.2025.104560","url":null,"abstract":"<div><div>In this paper, the long time behavior for a two-species Lotka-Volterra reaction-diffusion system with strong competition in a periodic medium is concerned. We prove that under the compactly supported initial values, the solutions of Cauchy problem converge to a pair of diverging pulsating fronts. Further, we obtain a sufficient condition for solutions to converge to <strong><em>1</em></strong> with two different speeds to the left and right. Due to the spatial heterogeneity, the pulsating fronts depend on its direction and any pair of rightward and leftward wave speeds be asymmetrical. Therefore, our analysis mainly depends on constructing appropriate super- and subsolutions and using the comparison principle and asymptotic behavior of bistable pulsating fronts.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104560"},"PeriodicalIF":1.8,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841573","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}
Pub Date : 2025-12-24DOI: 10.1016/j.nonrwa.2025.104581
L.F. Gonçalves, A.C.T. Sánchez, D.J. Tonon
In this work, we establish an upper bound for the number of crossing limit cycles in a class of piecewise smooth dynamical systems. The system is formed by a linear rigid center and a rigid center governed by a homogeneous polynomial of even degree n, separated by the straight line . Our results complement the work of [1], which addressed the odd-degree case. Specifically, we prove that if the parameters satisfy , the system admits at most limit cycles. Furthermore, for the specific case , assuming d2 ≠ M2 and , we show that the system has at most one limit cycle, and this upper bound is attained. This study advances the analysis of this family of systems by covering the even-degree case under certain conditions on the affine transformation.
{"title":"Limit cycles on rigid piecewise smooth dynamical systems governed by even polynomials","authors":"L.F. Gonçalves, A.C.T. Sánchez, D.J. Tonon","doi":"10.1016/j.nonrwa.2025.104581","DOIUrl":"10.1016/j.nonrwa.2025.104581","url":null,"abstract":"<div><div>In this work, we establish an upper bound for the number of crossing limit cycles in a class of piecewise smooth dynamical systems. The system is formed by a linear rigid center and a rigid center governed by a homogeneous polynomial of even degree <em>n</em>, separated by the straight line <span><math><mrow><mi>x</mi><mo>=</mo><mn>0</mn></mrow></math></span>. Our results complement the work of [1], which addressed the odd-degree case. Specifically, we prove that if the parameters satisfy <span><math><mrow><msub><mi>d</mi><mn>2</mn></msub><mo>=</mo><msub><mi>M</mi><mn>2</mn></msub></mrow></math></span>, the system admits at most <span><math><mrow><mo>(</mo><mi>n</mi><mo>−</mo><mn>2</mn><mo>)</mo><mo>/</mo><mn>2</mn></mrow></math></span> limit cycles. Furthermore, for the specific case <span><math><mrow><mi>n</mi><mo>=</mo><mn>4</mn></mrow></math></span>, assuming <em>d</em><sub>2</sub> ≠ <em>M</em><sub>2</sub> and <span><math><mrow><msub><mi>d</mi><mn>2</mn></msub><mo>=</mo><mn>0</mn></mrow></math></span>, we show that the system has at most one limit cycle, and this upper bound is attained. This study advances the analysis of this family of systems by covering the even-degree case under certain conditions on the affine transformation.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104581"},"PeriodicalIF":1.8,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841571","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}
Pub Date : 2025-12-24DOI: 10.1016/j.nonrwa.2025.104584
Ifeanyi Sunday Onah
This study develops and analyzes a seasonally forced malaria transmission model that incorporates vaccination, treatment, and the emergence of drug-resistant parasite strains. Using the periodic next-generation approach, we derive the vaccination-adjusted basic reproduction number Rv and establish conditions for the stability of the disease-free periodic solution. When Rv < 1, we show that malaria cannot persist and the disease-free state is globally asymptotically stable. Conversely, for Rv > 1, the infection is uniformly persistent and the system admits at least one positive T-periodic solution. A reduced autonomous version of the model reveals biologically interpretable thresholds for the dominance of either sensitive or resistant strains as well as coexistence scenarios. The model is calibrated using monthly malaria case data from Nigeria (2018–2024). The estimated reproduction number remains consistently above unity, indicating that malaria transmission is sustained under current intervention levels. Numerical simulations confirm these analytical results and illustrate the influence of vaccination coverage and drug resistance on long-term disease dynamics. Our findings highlight the need for strengthened intervention strategies to reduce Rv below one and interrupt sustained transmission.
{"title":"Seasonal dynamics and control of malaria: A non-autonomous model incorporating vaccination and drug resistance","authors":"Ifeanyi Sunday Onah","doi":"10.1016/j.nonrwa.2025.104584","DOIUrl":"10.1016/j.nonrwa.2025.104584","url":null,"abstract":"<div><div>This study develops and analyzes a seasonally forced malaria transmission model that incorporates vaccination, treatment, and the emergence of drug-resistant parasite strains. Using the periodic next-generation approach, we derive the vaccination-adjusted basic reproduction number <em>R<sub>v</sub></em> and establish conditions for the stability of the disease-free periodic solution. When <em>R<sub>v</sub></em> < 1, we show that malaria cannot persist and the disease-free state is globally asymptotically stable. Conversely, for <em>R<sub>v</sub></em> > 1, the infection is uniformly persistent and the system admits at least one positive <em>T</em>-periodic solution. A reduced autonomous version of the model reveals biologically interpretable thresholds for the dominance of either sensitive or resistant strains as well as coexistence scenarios. The model is calibrated using monthly malaria case data from Nigeria (2018–2024). The estimated reproduction number remains consistently above unity, indicating that malaria transmission is sustained under current intervention levels. Numerical simulations confirm these analytical results and illustrate the influence of vaccination coverage and drug resistance on long-term disease dynamics. Our findings highlight the need for strengthened intervention strategies to reduce <em>R<sub>v</sub></em> below one and interrupt sustained transmission.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104584"},"PeriodicalIF":1.8,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841572","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}
Pub Date : 2025-12-24DOI: 10.1016/j.nonrwa.2025.104580
Leander Claes , Michael Winkler
<div><div>In bounded <em>n</em>-dimensional domains with <em>n</em> ≥ 1, this manuscript examines an initial-boundary value problem for the system<span><span><span><math><mtable><mtr><mtd><mrow><mo>{</mo><mtable><mtr><mtd><mrow><msub><mi>u</mi><mrow><mi>t</mi><mi>t</mi></mrow></msub><mo>=</mo><mi>∇</mi><mo>·</mo><mrow><mo>(</mo><mi>γ</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mi>∇</mi><msub><mi>u</mi><mi>t</mi></msub><mo>)</mo></mrow><mo>+</mo><mi>a</mi><mi>∇</mi><mo>·</mo><mrow><mo>(</mo><mi>γ</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mi>∇</mi><mi>u</mi><mo>)</mo></mrow><mo>+</mo><mi>∇</mi><mo>·</mo><mi>f</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mo>,</mo></mrow></mtd></mtr><mtr><mtd><mrow><msub><mstyle><mi>Θ</mi></mstyle><mi>t</mi></msub><mo>=</mo><mi>D</mi><mstyle><mi>Δ</mi></mstyle><mstyle><mi>Θ</mi></mstyle><mo>+</mo><mstyle><mi>Γ</mi></mstyle><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><msup><mrow><mo>|</mo><mi>∇</mi><msub><mi>u</mi><mi>t</mi></msub><mo>|</mo></mrow><mn>2</mn></msup><mo>+</mo><mi>F</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mo>·</mo><mi>∇</mi><msub><mi>u</mi><mi>t</mi></msub><mo>,</mo></mrow></mtd></mtr></mtable></mrow></mtd></mtr></mtable></math></span></span></span>which in the case <span><math><mrow><mi>n</mi><mo>=</mo><mn>1</mn></mrow></math></span> and with <em>γ</em> ≡ Γ as well as <em>f</em> ≡ <em>F</em> reduces to the classical model for the evolution of displacement and temperatures in thermoviscoelasticity. Unlike in previous related studies, the focus here is on situations in which besides <em>f</em> and <em>F</em>, also the core ingredients <em>γ</em> and Γ may depend on the temperature variable Θ. Firstly, a statement on local existence of classical solutions is derived for arbitrary <em>a</em> > 0, <em>D</em> > 0 as well as 0 < <em>γ</em> ∈ <em>C</em><sup>2</sup>([0, ∞)) and 0 ≤ Γ ∈ <em>C</em><sup>1</sup>([0, ∞)), for functions <span><math><mrow><mi>f</mi><mo>∈</mo><msup><mi>C</mi><mn>2</mn></msup><mrow><mo>(</mo><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>;</mo><msup><mi>R</mi><mi>n</mi></msup><mo>)</mo></mrow></mrow></math></span> and <span><math><mrow><mi>F</mi><mo>∈</mo><msup><mi>C</mi><mn>1</mn></msup><mrow><mo>(</mo><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>;</mo><msup><mi>R</mi><mi>n</mi></msup><mo>)</mo></mrow></mrow></math></span> with <span><math><mrow><mi>F</mi><mo>(</mo><mn>0</mn><mo>)</mo><mo>=</mo><mn>0</mn></mrow></math></span>, and for suitably regular initial data of arbitrary size. Secondly, it is seen that under an additional assumption on smallness of <em>a, f</em>′ and <em>F</em>, as well as on the deviation of the initial data from the constant state given by <span><math><mrow><mi>u</mi><mo>=</mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mstyle><mi>Θ</mi></mstyle><mo>=</mo><msub><mstyle><mi>Θ</mi></mstyle><mi>★</mi>
{"title":"Describing smooth small-data solutions to a quasilinear hyperbolic-parabolic system by W1,p energy analysis","authors":"Leander Claes , Michael Winkler","doi":"10.1016/j.nonrwa.2025.104580","DOIUrl":"10.1016/j.nonrwa.2025.104580","url":null,"abstract":"<div><div>In bounded <em>n</em>-dimensional domains with <em>n</em> ≥ 1, this manuscript examines an initial-boundary value problem for the system<span><span><span><math><mtable><mtr><mtd><mrow><mo>{</mo><mtable><mtr><mtd><mrow><msub><mi>u</mi><mrow><mi>t</mi><mi>t</mi></mrow></msub><mo>=</mo><mi>∇</mi><mo>·</mo><mrow><mo>(</mo><mi>γ</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mi>∇</mi><msub><mi>u</mi><mi>t</mi></msub><mo>)</mo></mrow><mo>+</mo><mi>a</mi><mi>∇</mi><mo>·</mo><mrow><mo>(</mo><mi>γ</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mi>∇</mi><mi>u</mi><mo>)</mo></mrow><mo>+</mo><mi>∇</mi><mo>·</mo><mi>f</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mo>,</mo></mrow></mtd></mtr><mtr><mtd><mrow><msub><mstyle><mi>Θ</mi></mstyle><mi>t</mi></msub><mo>=</mo><mi>D</mi><mstyle><mi>Δ</mi></mstyle><mstyle><mi>Θ</mi></mstyle><mo>+</mo><mstyle><mi>Γ</mi></mstyle><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><msup><mrow><mo>|</mo><mi>∇</mi><msub><mi>u</mi><mi>t</mi></msub><mo>|</mo></mrow><mn>2</mn></msup><mo>+</mo><mi>F</mi><mrow><mo>(</mo><mstyle><mi>Θ</mi></mstyle><mo>)</mo></mrow><mo>·</mo><mi>∇</mi><msub><mi>u</mi><mi>t</mi></msub><mo>,</mo></mrow></mtd></mtr></mtable></mrow></mtd></mtr></mtable></math></span></span></span>which in the case <span><math><mrow><mi>n</mi><mo>=</mo><mn>1</mn></mrow></math></span> and with <em>γ</em> ≡ Γ as well as <em>f</em> ≡ <em>F</em> reduces to the classical model for the evolution of displacement and temperatures in thermoviscoelasticity. Unlike in previous related studies, the focus here is on situations in which besides <em>f</em> and <em>F</em>, also the core ingredients <em>γ</em> and Γ may depend on the temperature variable Θ. Firstly, a statement on local existence of classical solutions is derived for arbitrary <em>a</em> > 0, <em>D</em> > 0 as well as 0 < <em>γ</em> ∈ <em>C</em><sup>2</sup>([0, ∞)) and 0 ≤ Γ ∈ <em>C</em><sup>1</sup>([0, ∞)), for functions <span><math><mrow><mi>f</mi><mo>∈</mo><msup><mi>C</mi><mn>2</mn></msup><mrow><mo>(</mo><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>;</mo><msup><mi>R</mi><mi>n</mi></msup><mo>)</mo></mrow></mrow></math></span> and <span><math><mrow><mi>F</mi><mo>∈</mo><msup><mi>C</mi><mn>1</mn></msup><mrow><mo>(</mo><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow><mo>;</mo><msup><mi>R</mi><mi>n</mi></msup><mo>)</mo></mrow></mrow></math></span> with <span><math><mrow><mi>F</mi><mo>(</mo><mn>0</mn><mo>)</mo><mo>=</mo><mn>0</mn></mrow></math></span>, and for suitably regular initial data of arbitrary size. Secondly, it is seen that under an additional assumption on smallness of <em>a, f</em>′ and <em>F</em>, as well as on the deviation of the initial data from the constant state given by <span><math><mrow><mi>u</mi><mo>=</mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mstyle><mi>Θ</mi></mstyle><mo>=</mo><msub><mstyle><mi>Θ</mi></mstyle><mi>★</mi>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104580"},"PeriodicalIF":1.8,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841569","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}
Pub Date : 2025-12-23DOI: 10.1016/j.nonrwa.2025.104573
Rafael Muñoz-Sola
The aim of this paper is to study a model of electromagnetic levitation for a metallic rigid body. The model is constituted by the transient linear model of eddy currents under the hypothesis of axisymmetry, written in terms of a magnetic potential vector, coupled with an ODE which governs the vertical motion of the body. The electromagnetic model is a parabolic-elliptic PDE which parabolicity region is the position occupied by the body, which changes with time. Besides, Lorentz force appears in the RHS of the ODE. Thus, the model exhibits a coupling of geometrical nature. We establish the existence and uniqueness of solution of the coupled problem and we study its maximally defined solution. In particular, we prove that a blow-up of the velocity of the body cannot happen. Our techniques involve: a reformulation of the coupled problem as a causal differential equation, an adaptation of the theory about this kind of equations and a result of locally Lipschitz dependence of the magnetic potential vector with respect to the velocity of the body.
{"title":"Mathematical analysis of a levitation model","authors":"Rafael Muñoz-Sola","doi":"10.1016/j.nonrwa.2025.104573","DOIUrl":"10.1016/j.nonrwa.2025.104573","url":null,"abstract":"<div><div>The aim of this paper is to study a model of electromagnetic levitation for a metallic rigid body. The model is constituted by the transient linear model of eddy currents under the hypothesis of axisymmetry, written in terms of a magnetic potential vector, coupled with an ODE which governs the vertical motion of the body. The electromagnetic model is a parabolic-elliptic PDE which parabolicity region is the position occupied by the body, which changes with time. Besides, Lorentz force appears in the RHS of the ODE. Thus, the model exhibits a coupling of geometrical nature. We establish the existence and uniqueness of solution of the coupled problem and we study its maximally defined solution. In particular, we prove that a blow-up of the velocity of the body cannot happen. Our techniques involve: a reformulation of the coupled problem as a causal differential equation, an adaptation of the theory about this kind of equations and a result of locally Lipschitz dependence of the magnetic potential vector with respect to the velocity of the body.</div></div>","PeriodicalId":49745,"journal":{"name":"Nonlinear Analysis-Real World Applications","volume":"91 ","pages":"Article 104573"},"PeriodicalIF":1.8,"publicationDate":"2025-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841567","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}