Now showing items 1-20 of 166

    • A basic model for the propagation of ideologies 

      Mata Boschini, Luis Diego; Salas Jiménez, Eduardo; Sánchez Peña, Fabio Ariel (2022-11)
      Ideas and ideologies move the world and are involved in almost every aspect of human life and society. This paper presents a mathematical model for the propagation of two different ideologies in a group of people that could ...
    • A brief survey of Higgs bundles 

      Zúñiga Rojas, Ronald Alberto (2019-06)
      Considering a compact Riemann surface of genus greater or equal than two, a Higgs bundle is a pair composed of a holomorphic bundle over the Riemann surface, joint with an auxiliar vector field, so-called Higgs field. This ...
    • A Geometric Splitting Theorem 

      Rosales Ortega, José (2019)
      Let G = G1...Gl be a connected noncompact semisimple Lie group with Lie algebra g = g_1+g_2+....+ g_l acting topologically transitive on a manifold M. We obtain a geometric splitting of the metric on M that consider ...
    • A mathematical model with nonlinear relapse: conditions for a forward-backward bifurcation 

      Sánchez Peña, Fabio Ariel; Arroyo Esquivel, Jorge; Calvo Alpízar, Juan Gabriel (2023)
      We constructed a Susceptible-Addicted-Reformed model and explored the dynamics of nonlinear relapse in the Reformed population. The transition from susceptible considered at-risk is modeled using a strictly decreasing ...
    • A mixed-primal finite element approximation of a sedimentation–consolidation system 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2016)
      This paper is devoted to the mathematical and numerical analysis of a strongly cou- pled flow and transport system typically encountered in continuum-based models of sedimentation–consolidation processes. The model focuses ...
    • A mixed-primal finite element method for the coupling of Brinkman-Darcy flow and nonlinear transport. 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2021-01)
      This paper is devoted to the mathematical and numerical analysis of a model describing the interfacial flow-transport interaction in a porous-fluidic domain. The medium consists of a highly permeable material, where the ...
    • A Multilayer Network Model implementation for COVID-19 

      Calvo Alpízar, Juan Gabriel; Sánchez Peña, Fabio Ariel; Barboza Chinchilla, Luis Alberto; García Puerta, Yury Elena; Vásquez Brenes, Paola Andrea (2021)
      We present a numerical implementation for a multilayer network to model the transmission of Covid-19 or other diseases with a similar transmission mechanism. The model incorporates different contact types between individuals ...
    • A multilayer network model of Covid-19: implications in public health policy in Costa Rica 

      Sánchez Peña, Fabio Ariel; Calvo Alpízar, Juan Gabriel; Mery Valdovinos, Gustavo Andrés; García Puerta, Yury Elena; Vásquez Brenes, Paola Andrea; Barboza Chinchilla, Luis Alberto; Pérez Rosales, María Dolores; Rivas Chaves, Tania (2022-05)
      Successful partnerships between researchers, experts, and public health authorities have been critical to navigate the challenges of the Covid-19 pandemic worldwide. In this collaboration, mathematical models have played ...
    • A nonlinear relapse model with disaggregated contact rates: Analysis of a forward-backward bifurcation 

      Calvo Monge, Jimmy José; Sánchez Peña, Fabio Ariel; Calvo Alpízar, Juan Gabriel; Mena Arias, Darío Alberto (2023-09)
      Throughout the progress of epidemic scenarios, individuals in different health classes are expected to have different average daily contact behavior. This contact heterogeneity has been studied in recent adaptive models ...
    • A nonperturbative form of the spectral action principle in noncommutative geometry 

      Figueroa González, Héctor; Gracia Bondía, José M.; Lizzi, Fedele; Várilly Boyle, Joseph C. (1998-07)
      Using the formalism of superconnections, we show the existence of a bosonic action functional for the standard K-cycle in noncommutative geometry, giving rise, through the spectral action principle, only to the Einstein ...
    • A numerical implementation for the high-order 2D Virtual Element Method in MATLAB 

      Herrera Garro, César; Corrales Barquero, Ricardo; Arroyo Esquivel, Jorge; Calvo Alpízar, Juan Gabriel (2021)
      We present a numerical implementation for the Virtual Element Method that in- corporates high order spaces. We include all the required computations in order to assemble the stiffness and mass matrices, and right hand ...
    • A partial differential equation model with age-structure and nonlinear recidivism: Conditions for a backward bifurcation and a general numerical implementation 

      Sánchez Peña, Fabio Ariel; Calvo Alpízar, Juan Gabriel; Segura Ugalde, Esteban; Feng, Zhilan (2019-12-15)
      We formulate an age-structured three-staged nonlinear partial differential equation model that features nonlinear recidivism to the infected (infectious) class from the temporarily recovered class. Equilibria are computed, ...
    • A posteriori error analysis of a fully-mixed formulation for the Brinkman–Darcy problem 

      Álvarez Guadamuz, Mario Andrés; Gatica Pérez, Gabriel Nibaldo; Ruiz Baier, Ricardo (2017-09-05)
      We develop the a posteriori error analysis for a mixed finite element method applied to the coupling of Brinkman and Darcy equations in 3D, modelling the interaction of viscous and non-viscous flow effects across a given ...
    • A posteriori error analysis of mixed finite element methods for stress-assisted diffusion problems 

      Gatica Pérez, Gabriel Nibaldo; Gómez Vargas, Bryan Andrés; Ruiz Baier, Ricardo (2022)
      We develop the a posteriori error analysis for mixed-primal and fully-mixed finite element methods approximating the stress-assisted diffusion of solutes in elastic materials. The systems are formulated in terms of stress, ...
    • A two-level overlapping Schwarz method for H(curl) in two dimensions with irregular subdomains 

      Calvo Alpízar, Juan Gabriel (2015-10-07)
      A bound is obtained for the condition number of a two-level overlapping Schwarz algorithm for problems posed in H(curl) in two dimensions, where the subdomains are only assumed to be John subdomains. The coarse space is ...
    • A two-patch epidemic model with nonlinear reinfection 

      Calvo Alpízar, Juan Gabriel; Hernádez Alvarado, Alberto José; Porter, Mason A.; Sánchez Peña, Fabio Ariel (2020)
      The propagation of infectious diseases and its impact on individuals play a major role in disease dynamics, and it is important to incorporate population heterogeneity into efforts to study diseases. As a simplistic but ...
    • Adicción a Redes Sociales: Un Modelo Matemático 

      Garro, Valeria; Masís, Juan J.; Alarcón, Greivin J.; Campos, Camilo D.; Castro, Jorge A.; León, Juan M.; Sánchez Peña, Fabio Ariel (2023)
      El artículo presenta un modelo de dinámica social para el estudio de la adicción a las redes sociales, basado en los modelos matemáticos SIR (Susceptibles-Infectados-Recuperados). El modelo considera cinco categorías de ...
    • Algebras of distributions suitable for phase-space quantum mechanics. III. The dual space of the algebra L_b(S) 

      Gracia Bondía, José M.; Várilly Boyle, Joseph C.; Figueroa González, Héctor (1989-09)
      The strong dual space of the topological algebra L_b(S), where S is the Schwartz space of smooth declining functions on R, may be obtained as an inductive limit of projective limits of Hilbert spaces. To that end, we ...
    • Algebras of distributions suitable for phase‐space quantum mechanics. I 

      Gracia Bondía, José M.; Várilly Boyle, Joseph C. (1988-06-04)
      The twisted product of functions on R^2N is extended to a *-algebra of tempered distributions which contains the rapidly decreasing smooth functions, the distributions of compact support, and all polynomials, and moreover ...
    • Algebras of distributions suitable for phase‐space quantum mechanics. II. Topologies on the Moyal algebra 

      Várilly Boyle, Joseph C.; Gracia Bondía, José M. (1988-06-04)
      The topology of the Moyal *-algebra may be defined in three ways: the algebra may be regarded as an operator algebra over the space of smooth declining functions either on the configuration space or on the phase space ...