Results 81 to 90 of about 278,137 (249)

Hybrid Reaction–Diffusion Epidemic Models: Dynamics and Emergence of Oscillations

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT In this paper, we construct a hybrid epidemic mathematical model based on a reaction–diffusion system of the SIR (susceptible‐infected‐recovered) type. This model integrates the impact of random factors on the transmission rate of infectious diseases, represented by a probabilistic process acting at discrete time steps.
Asmae Tajani, Cristiana J. Silva, Guillaume Cantin   +2 more
wiley   +1 more source

Unbounded quantum graphs with unbounded boundary conditions

, 2012
We consider metric graphs with a uniform lower bound on the edge lengths but no further restrictions. We discuss how to describe every local self-adjoint Laplace operator on such graphs by boundary conditions in the vertices given by projections and self-
Adams, Arens, Berkolaiko, Brüning, Buschmann, Carlson, Carlson, Cheon, Derkach, Everitt, Exner, Harmer, Kostenko, Kostrykin, Kostrykin, Kuchment, Post, Schubert   +17 more
core   +1 more source

Duality for Evolutionary Equations With Applications to Null Controllability

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT We study evolutionary equations in exponentially weighted L2$$ {\mathrm{L}}^2 $$‐spaces as introduced by Picard in 2009. First, for a given evolutionary equation, we explicitly describe the ν$$ \nu $$‐adjoint system, which turns out to describe a system backwards in time. We prove well‐posedness for the ν$$ \nu $$‐adjoint system. We then apply
Andreas Buchinger, Christian Seifert
wiley   +1 more source

Adjoint and self-adjoint differential operators on graphs

Electronic Journal of Differential Equations, 1998
A differential operator on a directed graph with weighted edges is characterized as a system of ordinary differential operators. A class of local operators is introduced to clarify which operators should be considered as defined on the graph.
Robert Carlson
doaj  

Immigration et criminalisation au Canada : état des lieux

Criminologie, 2019
Les intersections entre immigration et criminalisation sont nombreuses. Au Canada, près de 20 ans après l’entrée en vigueur de la Loi sur l’immigration et la protection des réfugiés (LIPR) et à la suite de plusieurs arrêts importants de la Cour suprême ...
David Moffette
doaj   +1 more source

New classes of nonlinearly self-adjoint evolution equations of third- and fifth-order

, 2012
In a recent communication Nail Ibragimov introduced the concept of nonlinearly self-adjoint differential equation [N. H. Ibragimov, Nonlinear self-adjointness and conservation laws, J. Phys. A: Math. Theor., vol. 44, 432002, 8 pp., (2011)].
Bilige, Bruzón, Freire, Freire, Freire, Freire, Gandarias, Gandarias, Gandarias, Gandarias, Gómez, Ibragimov, Ibragimov, Ibragimov, Ibragimov, Ibragimov, Ibragimov, Ibragimov, Ibragimov, Igor Leite Freire, Qu, Reyes, Yang, You, Yu   +24 more
core   +1 more source

Shape Derivatives of the Eigenvalues of the De Rham Complex for Lipschitz Deformations and Variable Coefficients: Part I

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT We study eigenvalue problems for the de Rham complex on varying three‐dimensional domains. Our analysis includes the Helmholtz equation as well as the Maxwell system with mixed boundary conditions and non‐constant coefficients. We provide Hadamard‐type formulas for the shape derivatives under weak regularity assumptions on the domain and its ...
Pier Domenico Lamberti, Dirk Pauly, Michele Zaccaron   +2 more
wiley   +1 more source

Spectral analysis of reaction-diffusion systems via physics-informed neural networks

AIMS Mathematics
Reaction–diffusion systems serve as a powerful mathematical framework for modeling dynamic behaviors and pattern formation, widely used to model physical, chemical, and biological systems, among others.
Burhan Bezekci
doaj   +1 more source

De la sécurité privée à l’armée de destruction massive. La « bande armée » et la criminalité de masse

Criminologie, 2012
Dans cet article, nous nous intéressons à la mobilisation et la participation d’une bande armée – les Scorpions – dans les événements qui se sont produits en ex-Yougoslavie, durant les années 1990.
Samuel Tanner
doaj   +1 more source

Asymptotics for the Spectrum of the Laplacian in Thin Bars with Varying Cross Sections

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT We consider spectral problems for the Laplace operator in 3D rod structures with a small cross section of diameter O(ε)$$ O\left(\varepsilon \right) $$, ε$$ \varepsilon $$ being a positive parameter. The boundary conditions are Dirichlet (Neumann, respectively) on the bases of this structure, and Neumann on the lateral boundary.
Pablo Benavent‐Ocejo, Delfina Gómez, Maria‐Eugenia Pérez‐Martínez   +2 more
wiley   +1 more source