SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 215-245, February 2024. Abstract. We develop the steady-state regularized 13-moment equations in the linear regime for rarefied gas dynamics with general collision models. For small Knudsen numbers, the model is accurate up to the super-Burnett order, and the resulting system of moment equations is shown to have a symmetric structure. We also propose Onsager boundary conditions for the moment equations that guarantee the stability of the equations. The validity of our model is verified by benchmark examples for the one-dimensional channel flows.
{"title":"Linear Regularized 13-Moment Equations with Onsager Boundary Conditions for General Gas Molecules","authors":"Zhenning Cai, Manuel Torrilhon, Siyao Yang","doi":"10.1137/23m1556472","DOIUrl":"https://doi.org/10.1137/23m1556472","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 215-245, February 2024. <br/> Abstract. We develop the steady-state regularized 13-moment equations in the linear regime for rarefied gas dynamics with general collision models. For small Knudsen numbers, the model is accurate up to the super-Burnett order, and the resulting system of moment equations is shown to have a symmetric structure. We also propose Onsager boundary conditions for the moment equations that guarantee the stability of the equations. The validity of our model is verified by benchmark examples for the one-dimensional channel flows.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"39 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139668694","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}
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 189-214, February 2024. Abstract. To overcome some limits of classical neuronal models, we propose a Markovian generalization of the classical model based on Jacobi processes by introducing downwards jumps to describe the activity of a single neuron. The statistical analysis of interspike intervals is performed by studying the first passage times of the proposed Markovian Jacobi process with jumps through a constant boundary. In particular, we characterize its Laplace transform, which is expressed in terms of some generalization of hypergeometric functions that we introduce, and deduce a closed-form expression for its expectation. Our approach, which is original in the context of first-passage-time problems, relies on intertwining relations between the semigroups of the classical Jacobi process and its generalization, which have been recently established in [P. Cheridito et al., J. Ec. Polytech. - Math., 8 (2021), pp. 331–378]. A numerical investigation of the firing rate of the considered neuron is performed for some choices of the involved parameters and of the jump distributions.
{"title":"Jacobi Processes with Jumps as Neuronal Models: A First Passage Time Analysis","authors":"Giuseppe D’Onofrio, Pierre Patie, Laura Sacerdote","doi":"10.1137/22m1516877","DOIUrl":"https://doi.org/10.1137/22m1516877","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 189-214, February 2024. <br/> Abstract. To overcome some limits of classical neuronal models, we propose a Markovian generalization of the classical model based on Jacobi processes by introducing downwards jumps to describe the activity of a single neuron. The statistical analysis of interspike intervals is performed by studying the first passage times of the proposed Markovian Jacobi process with jumps through a constant boundary. In particular, we characterize its Laplace transform, which is expressed in terms of some generalization of hypergeometric functions that we introduce, and deduce a closed-form expression for its expectation. Our approach, which is original in the context of first-passage-time problems, relies on intertwining relations between the semigroups of the classical Jacobi process and its generalization, which have been recently established in [P. Cheridito et al., J. Ec. Polytech. - Math., 8 (2021), pp. 331–378]. A numerical investigation of the firing rate of the considered neuron is performed for some choices of the involved parameters and of the jump distributions.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"9 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139668699","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}
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 165-188, February 2024. Abstract. We consider the problem of elastic diffraction tomography, which consists in reconstructing elastic properties (i.e., mass density and elastic Lamé parameters) of a weakly scattering medium from full-field data of scattered waves outside the medium. Elastic diffraction tomography refers to the elastic inverse scattering problem after linearization using a first-order Born approximation. In this paper, we prove the Fourier diffraction theorem, which relates the two-dimensional Fourier transform of scattered waves with the Fourier transform of the scatterer in the three-dimensional spatial Fourier domain. Elastic wave mode separation is performed, which decomposes a wave into five modes. A new two-step inversion process is developed, providing information on the modes first and second on the elastic parameters. Finally, we discuss reconstructions with plane wave excitation experiments for different tomographic setups and with different plane wave excitation frequencies, respectively.
{"title":"An Inversion Scheme for Elastic Diffraction Tomography Based on Mode Separation","authors":"Bochra Mejri, Otmar Scherzer","doi":"10.1137/22m1538909","DOIUrl":"https://doi.org/10.1137/22m1538909","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 165-188, February 2024. <br/> Abstract. We consider the problem of elastic diffraction tomography, which consists in reconstructing elastic properties (i.e., mass density and elastic Lamé parameters) of a weakly scattering medium from full-field data of scattered waves outside the medium. Elastic diffraction tomography refers to the elastic inverse scattering problem after linearization using a first-order Born approximation. In this paper, we prove the Fourier diffraction theorem, which relates the two-dimensional Fourier transform of scattered waves with the Fourier transform of the scatterer in the three-dimensional spatial Fourier domain. Elastic wave mode separation is performed, which decomposes a wave into five modes. A new two-step inversion process is developed, providing information on the modes first and second on the elastic parameters. Finally, we discuss reconstructions with plane wave excitation experiments for different tomographic setups and with different plane wave excitation frequencies, respectively.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"14 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139668564","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}
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 114-138, February 2024. Abstract. The mechanism of seed dispersal mutualism is fundamental to understanding vegetation diversity and its conservation. In this study, we propose a stochastic model that extends the classical framework of seed dispersal mutualism to explore the effects of environmental stochasticity on mutualistic interactions between seed dispersers and plants. We first provide a comprehensive picture of the long-term dynamics of seed dispersal mutualism in deterministic and stochastic environments. We then analyze the relationship between stochasticity and the probability and time that seed dispersal mutualism tips between stable states. Additionally, we evaluate the extinction risk of seed dispersal mutualism for different population values and accordingly assign extinction warning levels to these values. The analysis reveals that the impact of environmental stochasticity on tipping phenomena is scenario-dependent but follows some interpretable trends. The probability (resp., time) of tipping towards the extinction state typically increases (resp., decreases) monotonically with noise intensity, while the probability of tipping towards the coexistence state typically peaks at intermediate noise intensity. Noise in animal populations contributes to tipping toward the coexistence state, whereas noise in plant populations slows down the tipping toward the coexistence state. Noise-induced changes in warning levels of initial population values are most pronounced near the boundaries of the basin of attraction, but sufficiently loud noise (especially for plant populations) may alter the risk far from these boundaries. These findings provide a theoretical explanation for the effect of environmental stochasticity on multistability transitions in seed dispersal mutualism and can be utilized to study the interplay between other population systems and environmental stochasticity.
{"title":"Tipping Points in Seed Dispersal Mutualism Driven by Environmental Stochasticity","authors":"Tao Feng, Zhipeng Qiu, Hao Wang","doi":"10.1137/22m1531579","DOIUrl":"https://doi.org/10.1137/22m1531579","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 114-138, February 2024. <br/> Abstract. The mechanism of seed dispersal mutualism is fundamental to understanding vegetation diversity and its conservation. In this study, we propose a stochastic model that extends the classical framework of seed dispersal mutualism to explore the effects of environmental stochasticity on mutualistic interactions between seed dispersers and plants. We first provide a comprehensive picture of the long-term dynamics of seed dispersal mutualism in deterministic and stochastic environments. We then analyze the relationship between stochasticity and the probability and time that seed dispersal mutualism tips between stable states. Additionally, we evaluate the extinction risk of seed dispersal mutualism for different population values and accordingly assign extinction warning levels to these values. The analysis reveals that the impact of environmental stochasticity on tipping phenomena is scenario-dependent but follows some interpretable trends. The probability (resp., time) of tipping towards the extinction state typically increases (resp., decreases) monotonically with noise intensity, while the probability of tipping towards the coexistence state typically peaks at intermediate noise intensity. Noise in animal populations contributes to tipping toward the coexistence state, whereas noise in plant populations slows down the tipping toward the coexistence state. Noise-induced changes in warning levels of initial population values are most pronounced near the boundaries of the basin of attraction, but sufficiently loud noise (especially for plant populations) may alter the risk far from these boundaries. These findings provide a theoretical explanation for the effect of environmental stochasticity on multistability transitions in seed dispersal mutualism and can be utilized to study the interplay between other population systems and environmental stochasticity.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"14 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139584171","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}
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 139-164, February 2024. Abstract. Starting from a nonlocal version of the Prigogine–Herman traffic model, we derive a natural hierarchy of kinetic discrete-velocity models for traffic flow consisting of systems of quasi-linear hyperbolic equations with relaxation terms. The hyperbolic main part of these models turns out to have several favorable features. In particular, we determine Riemann invariants and prove richness and total linear degeneracy of the hyperbolic systems. Moreover, a physically reasonable invariant domain is obtained for all equations of the hierarchy. Additionally, we investigate the full relaxation system with respect to stability and persistence of periodic (stop-and-go-type) solutions and derive a condition for the appearance of such solutions. Finally, numerical results for various situations are presented, illustrating the analytical findings.
{"title":"A Hierarchy of Kinetic Discrete-Velocity Models for Traffic Flow Derived from a Nonlocal Prigogine–Herman Model","authors":"R. Borsche, A. Klar","doi":"10.1137/23m1583065","DOIUrl":"https://doi.org/10.1137/23m1583065","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 139-164, February 2024. <br/> Abstract. Starting from a nonlocal version of the Prigogine–Herman traffic model, we derive a natural hierarchy of kinetic discrete-velocity models for traffic flow consisting of systems of quasi-linear hyperbolic equations with relaxation terms. The hyperbolic main part of these models turns out to have several favorable features. In particular, we determine Riemann invariants and prove richness and total linear degeneracy of the hyperbolic systems. Moreover, a physically reasonable invariant domain is obtained for all equations of the hierarchy. Additionally, we investigate the full relaxation system with respect to stability and persistence of periodic (stop-and-go-type) solutions and derive a condition for the appearance of such solutions. Finally, numerical results for various situations are presented, illustrating the analytical findings.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"12 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139584175","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}
Isaac Klapper, Daniel B. Szyld, Xinli Yu, Karsten Zengler, Tianyu Zhang, Cristal Zúñiga
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 97-113, February 2024. Abstract. Microbes are able to deploy different strategies in response to, and depending upon, local environmental conditions. In the setting of a microbial community, this property induces a Nash equilibrium problem because access to environmental resources is bounded. If microbes are also distributed in space, then those resources are subject to transport limitations (encoded in a PDE) and so microbial strategies at one location influence resources and, hence, microbial strategies, at another. Here we formulate the resulting PDE-coupled generalized Nash equilibrium problem for a multispecies biofilm community, and propose a domain-decomposition-based method for its solution. An example consisting of a model with two microbial species biofilm with 33 externally transported chemical concentrations is presented.
{"title":"A Domain Decomposition Method for Solution of a PDE-Constrained Generalized Nash Equilibrium Model of Biofilm Community Metabolism","authors":"Isaac Klapper, Daniel B. Szyld, Xinli Yu, Karsten Zengler, Tianyu Zhang, Cristal Zúñiga","doi":"10.1137/22m1511023","DOIUrl":"https://doi.org/10.1137/22m1511023","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 97-113, February 2024. <br/> Abstract. Microbes are able to deploy different strategies in response to, and depending upon, local environmental conditions. In the setting of a microbial community, this property induces a Nash equilibrium problem because access to environmental resources is bounded. If microbes are also distributed in space, then those resources are subject to transport limitations (encoded in a PDE) and so microbial strategies at one location influence resources and, hence, microbial strategies, at another. Here we formulate the resulting PDE-coupled generalized Nash equilibrium problem for a multispecies biofilm community, and propose a domain-decomposition-based method for its solution. An example consisting of a model with two microbial species biofilm with 33 externally transported chemical concentrations is presented.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"230 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139555071","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}
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 75-96, February 2024. Abstract. This article presents a new method to reconstruct slowly varying width defects in two-dimensional waveguides using one-side section measurements at locally resonant frequencies. At these frequencies, locally resonant modes propagate in the waveguide up to a “cut-off” position. In this particular point, the local width of the waveguide can be recovered. Given multifrequency data measured on a section of the waveguide, we perform an efficient layer stripping approach to recover, section by section, the shape variations. It provides an L infinity-stable method to reconstruct the width of a slowly monotonous varying waveguide. We validate this method on numerical data and discuss its limits.
{"title":"Layer Stripping Approach to Reconstruct Shape Variations in Waveguides Using Locally Resonant Frequencies","authors":"Angéle Niclas, Laurent Seppecher","doi":"10.1137/23m1546336","DOIUrl":"https://doi.org/10.1137/23m1546336","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 75-96, February 2024. <br/> Abstract. This article presents a new method to reconstruct slowly varying width defects in two-dimensional waveguides using one-side section measurements at locally resonant frequencies. At these frequencies, locally resonant modes propagate in the waveguide up to a “cut-off” position. In this particular point, the local width of the waveguide can be recovered. Given multifrequency data measured on a section of the waveguide, we perform an efficient layer stripping approach to recover, section by section, the shape variations. It provides an L infinity-stable method to reconstruct the width of a slowly monotonous varying waveguide. We validate this method on numerical data and discuss its limits.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139517709","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}
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 60-74, February 2024. Abstract. Critical Reynolds numbers for the monotone exponential energy stability of Couette and Poiseuille plane flows were obtained by Orr in 1907 [Proc. Roy. Irish Acad. A, 27 (1907), pp. 9–68, 69–138] in a famous paper, and by Joseph in 1966 [J. Fluid Mech., 33 (1966), pp. 617–621], Joseph and Carmi in 1969 [Quart. Appl. Math., 26 (1969), pp. 575–579], and Busse in 1972 [Arch. Ration. Mech. Anal., 47 (1972), pp. 28–35]. All these authors obtained their results applying variational methods to compute the maximum of a functional ratio derived from the Reynolds–Orr energy identity. Orr and Joseph obtained different results; for instance, in the Couette case Orr computed the critical Reynolds value of 44.3 (on spanwise perturbations) and Joseph 20.65 (on streamwise perturbations). Recently in [P. Falsaperla, G. Mulone, and C. Perrone, Eur. J. Mech. B Fluids, 93 (2022), pp. 93–100], the authors conjectured that the search of the maximum should be restricted to a subspace of the space of kinematically admissible perturbations. With this conjecture, the critical nonlinear energy Reynolds number was found among spanwise perturbations (a Squire theorem for nonlinear systems). With a direct proof and an appropriate and original decomposition of the dissipation terms in the Reynolds–Orr identity we show the validity of this conjecture in the space of three-dimensional perturbations.
{"title":"Nonlinear Monotone Energy Stability of Plane Shear Flows: Joseph or Orr Critical Thresholds?","authors":"Giuseppe Mulone","doi":"10.1137/22m1535826","DOIUrl":"https://doi.org/10.1137/22m1535826","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 60-74, February 2024. <br/> Abstract. Critical Reynolds numbers for the monotone exponential energy stability of Couette and Poiseuille plane flows were obtained by Orr in 1907 [Proc. Roy. Irish Acad. A, 27 (1907), pp. 9–68, 69–138] in a famous paper, and by Joseph in 1966 [J. Fluid Mech., 33 (1966), pp. 617–621], Joseph and Carmi in 1969 [Quart. Appl. Math., 26 (1969), pp. 575–579], and Busse in 1972 [Arch. Ration. Mech. Anal., 47 (1972), pp. 28–35]. All these authors obtained their results applying variational methods to compute the maximum of a functional ratio derived from the Reynolds–Orr energy identity. Orr and Joseph obtained different results; for instance, in the Couette case Orr computed the critical Reynolds value of 44.3 (on spanwise perturbations) and Joseph 20.65 (on streamwise perturbations). Recently in [P. Falsaperla, G. Mulone, and C. Perrone, Eur. J. Mech. B Fluids, 93 (2022), pp. 93–100], the authors conjectured that the search of the maximum should be restricted to a subspace of the space of kinematically admissible perturbations. With this conjecture, the critical nonlinear energy Reynolds number was found among spanwise perturbations (a Squire theorem for nonlinear systems). With a direct proof and an appropriate and original decomposition of the dissipation terms in the Reynolds–Orr identity we show the validity of this conjecture in the space of three-dimensional perturbations.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"39 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139499964","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}
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 39-59, February 2024. Abstract. We identify a taxonomic property on the growth functions in the multispecies chemostat model which ensures the coexistence of a subset of species under periodic removal rate. We show that proportions of some powers of the species densities are periodic functions, leading to an infinity of distinct neutrally stable periodic orbits depending on the initial condition. This condition on the species for neutral stability possesses the feature to be independent of the shape of the periodic signal for a given mean value. We also give conditions allowing the coexistence of two distinct subsets of species. Although these conditions are nongeneric, we show in simulations that when these conditions are only approximately satisfied, the behavior of the solutions is close to that of the nongeneric case over a long time interval, justifying the interest of our study.
{"title":"Multiplicity of Neutrally Stable Periodic Orbits with Coexistence in the Chemostat Subject to Periodic Removal Rate","authors":"Thomas Guilmeau, Alain Rapaport","doi":"10.1137/23m1552450","DOIUrl":"https://doi.org/10.1137/23m1552450","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 39-59, February 2024. <br/> Abstract. We identify a taxonomic property on the growth functions in the multispecies chemostat model which ensures the coexistence of a subset of species under periodic removal rate. We show that proportions of some powers of the species densities are periodic functions, leading to an infinity of distinct neutrally stable periodic orbits depending on the initial condition. This condition on the species for neutral stability possesses the feature to be independent of the shape of the periodic signal for a given mean value. We also give conditions allowing the coexistence of two distinct subsets of species. Although these conditions are nongeneric, we show in simulations that when these conditions are only approximately satisfied, the behavior of the solutions is close to that of the nongeneric case over a long time interval, justifying the interest of our study.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"39 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139482962","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}
Michael Fischer, Laura Kanzler, Christian Schmeiser
SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 1-18, February 2024. Abstract. Repulsion between individuals within a finite radius is encountered in numerous applications, including cell exclusion, i.e., avoidance of overlapping cells, bird flocks, or microscopic pedestrian models. We define such individual-based particle dynamics in one spatial dimension with minimal assumptions of the repulsion force [math] as well as their external velocity [math] and prove their characteristic properties. Moreover, we are able to perform a rigorous limit from the microscopic to the macroscopic scale, where we could recover the finite interaction radius as a density threshold. Specific choices for the repulsion force [math] lead to well-known nonlinear diffusion equations on the macroscopic scale, as, e.g., the porous medium equation. At both scaling levels, numerical simulations are presented and compared to underline the analytical results.
{"title":"One-Dimensional Short-Range Nearest-Neighbor Interaction and Its Nonlinear Diffusion Limit","authors":"Michael Fischer, Laura Kanzler, Christian Schmeiser","doi":"10.1137/23m155520x","DOIUrl":"https://doi.org/10.1137/23m155520x","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 1, Page 1-18, February 2024. <br/> Abstract. Repulsion between individuals within a finite radius is encountered in numerous applications, including cell exclusion, i.e., avoidance of overlapping cells, bird flocks, or microscopic pedestrian models. We define such individual-based particle dynamics in one spatial dimension with minimal assumptions of the repulsion force [math] as well as their external velocity [math] and prove their characteristic properties. Moreover, we are able to perform a rigorous limit from the microscopic to the macroscopic scale, where we could recover the finite interaction radius as a density threshold. Specific choices for the repulsion force [math] lead to well-known nonlinear diffusion equations on the macroscopic scale, as, e.g., the porous medium equation. At both scaling levels, numerical simulations are presented and compared to underline the analytical results.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"51 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139459585","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}