Results 41 to 50 of about 3,595 (260)
Asymptotic Profiles of Basic Reproduction Number for Epidemic Spreading in Heterogeneous Environment [PDF]
SIAM Journal on Applied Mathematics, 2020 The effect of diffusion rates on the basic reproduction number of a general compartmental reaction-diffusion epidemic model in a heterogeneous environment is considered. It is shown when the diffusion rates tend to zero, the limit of the basic reproduction number is the maximum value of the local reproduction number on the spatial domain.
Shanshan Chen, Junping Shi
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A Q‐Learning Algorithm to Solve the Two‐Player Zero‐Sum Game Problem for Nonlinear Systems
International Journal of Adaptive Control and Signal Processing, Volume 39, Issue 3, Page 566-581, March 2025.A Q‐learning algorithm to solve the two‐player zero‐sum game problem for nonlinear systems. ABSTRACT This paper deals with the two‐player zero‐sum game problem, which is a bounded L2$$ {L}_2 $$‐gain robust control problem. Finding an analytical solution to the complex Hamilton‐Jacobi‐Issacs (HJI) equation is a challenging task.
Afreen Islam +2 more
wiley +1 more source
A Rumor-Spreading Model with Three Identical Time Delays
MathematicsUnderstanding the effect of time delays on rumor spreading is of special importance to curbing the spread of rumors. This article proposes a rumor-spreading model with three identical time delays: a delay associated with the negative influence of a ...
Chunlong Fu +4 more
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Asymptotic speed of spread and traveling waves for a nonlocalepidemic model
Discrete and Continuous Dynamical Systems - B, 2005 The authors consider the following reaction-diffusion system, which describes the dynamics of a nonlocal epidemic disease: \[ \begin{cases} \partial_t u_1 (t,x) = d\Delta u_1 (t,x) - a_{11}u_1 (t,x) + \int_{\mathbb{R}^n} K(x-y) u_2 (t,y)\,dy, \\ \partial_t u_2 (t,x) = - a_{22}u_2 (t,x) + g(u_1 (t,x)),\\ u_1 (0,x) = \phi_1 (x)\geq 0,\;\;\;u_2 (0,x ...
Xu, Dashun, Zhao, Xiao-Qiang
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Asymptotic-Preserving Neural Networks for multiscale hyperbolic models of epidemic spread
Mathematical Models and Methods in Applied Sciences, 2022 When investigating epidemic dynamics through differential models, the parameters needed to understand the phenomenon and to simulate forecast scenarios require a delicate calibration phase, often made even more challenging by the scarcity and uncertainty of the observed data reported by official sources.
Bertaglia, Giulia +3 more
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Karl Popper and the Mechanisms of Hydrogen Embrittlement
Advanced Engineering Materials, EarlyView.Representation of the beginning of loss of ductility rather than embrittlement. Small concentrations of hydrogen in a diffusible form within iron are well‐established to harm the mechanical integrity of steels. There are theories that attempt to explain the pernicious role of hydrogen.
H. K. D. H. Bhadeshia
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Minimal Wave Speed in an Integrodifference System of Predator-Prey Type
Discrete Dynamics in Nature and Society, 2020 This article studies the minimal wave speed of traveling wave solutions in an integrodifference predator-prey system that does not have the comparison principle. By constructing generalized upper and lower solutions and utilizing the theory of asymptotic
Baoju Sun, Fuzhen Wu
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Soft Mechanical‐Electrical Logic Using Liquid Metal‐Filled 3D‐Printed Architectures
Advanced Engineering Materials, EarlyView.We present 3D‐printed soft mechanical–electrical logic elements that use liquid metal–filled silicone tubes actuated by thermoplastic polyurethane/polylactic acid (TPU/PLA) architectures to produce Boolean operations. Complementary normally open and normally closed unit cells perform repeatable binary transitions and can be combined into more complex ...
Christoph Lehmann +2 more
wiley +1 more source
From Shear to Sound: Mechanics–Acoustics Mapping of TPMS Lattices
Advanced Engineering Materials, EarlyView.Triply periodic minimal surface (TPMS) lattices are mapped across mechanical and acoustic performance, revealing that descriptors validated in compression fail under shear. First‐time comparison with trusses included. A transition from porous to resonance‐driven absorption emerges at 25% density.
Lucía Doyle +3 more
wiley +1 more source
Modelling the biological invasion of Carcinus maenas (the European green crab)
Journal of Biological Dynamics, 2016 This paper proposes a system of integro-difference equations to model the spread of Carcinus maenas, commonly called the European green crab, that causes severe damage to coastal ecosystems. A model with juvenile and adult classes is first studied. Here,
Nathan G. Marculis, Roger Lui
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