Listar Matemática por procedencia "UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Matemáticas Puras y Aplicadas (CIMPA)"
Mostrando ítems 1-20 de 79
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A basic model for the propagation of ideologies
(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 BDDC algorithm with deluxe scaling for H(curl) in two dimensions with irregular subdomains
(2015)A bound is obtained for the condition number of a BDDC algorithm for problems posed in H(curl) in two dimensions, where the subdomains are only assumed to be uniform in the sense of Peter Jones. For the primal variable ... -
A mathematical model with nonlinear relapse: conditions for a forward-backward bifurcation
(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 Multilayer Network Model implementation for COVID-19
(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
(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 new coarse space for overlapping Schwarz algorithms for H(curl) problems in three dimensions with irregular subdomains
(2019)A new coarse space for a two-level overlapping Schwarz algorithm is presented for problems posed in three dimensions in the space H(curl, Ω). Previous studies for these methods are very restrictive about the geometry of ... -
A nonlinear relapse model with disaggregated contact rates: Analysis of a forward-backward bifurcation
(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 partial differential equation model with age-structure and nonlinear recidivism: Conditions for a backward bifurcation and a general numerical implementation
(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 two-level overlapping Schwarz method for H(curl) in two dimensions with irregular subdomains
(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
(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 ... -
A two-step estimation procedure for locally stationary ARMA processes with tempered stable innovations
(2023-03)The class of locally stationary processes assumes a time-varying (tv) spectral representation and finite second moment. Different areas have observed phenomena with heavy tail distributions or infinite variance. Using ... -
Adicción a Redes Sociales: Un Modelo Matemático
(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 ... -
An adaptive choice of primal constrains for BDDC domain decomposition algorithms
(2016-12-12)An adaptive choice for primal spaces based on parallel sums is developed for BDDC deluxe methods and elliptic problems in three dimensions. The primal space, which forms the global, coarse part of the domain decomposition ... -
An overlapping preconditioner for 2D virtual problems posed in H(rot) with irregular subdomains
(2022)We present a two-level overlapping Schwarz preconditioner for problems posed in H(rot) in two dimensions, that extends previous methods for Nédélec elements (triangular meshes) to general polygonal partitions (virtual ... -
An overlapping Schwarz method for virtual element discretizations in two dimensions
(2019)A new coarse space for domain decomposition methods is presented for nodal ellipticproblems in two dimensions. The coarse space is derived from the novel virtual elementmethods and therefore can accommodate quite irregular ... -
Analiticity of the Lyapunov exponents of random products of quasi-periodic cocycles
(2021-11-01)We show that the top Lyapunov exponent LE(p) associated with a random product of quasi-periodic cocycles depends real analytically on the transition probabilities p whenever LE(p) is simple. Moreover if the spectrum at ... -
Climate-Driven Statistical Models as Effective Predictors of Local Dengue Incidence in Costa Rica: A Generalized Additive Model and Random Forest Approach
(2019-12)Climate has been an important factor in shaping the distribution and incidence of dengue cases in tropical and subtropical countries. In CostaRica, a tropical country with distinctive micro-climates, dengue has been endemic ... -
Clustering binary data by application of combinatorial optimization heuristics
(2019-08-09)We study clustering methods for binary data, first defining aggregation criteria that measure the compactness of clusters. Five new and original methods are introduced, using neighborhoods and population behavior combinatorial ... -
Clustering via ant colonies: Parameter analysis and improvement of the algorithm
(2020-04-18)An ant colony optimization approach for partitioning a set of objects is proposed. In order to minimize the intra-variance, or within sum-of-squares, of the partitioned classes, we construct ant-like solutions by a ... -
Comparative analysis of dengue versus chikungunya outbreaks in Costa Rica
(2018-06)For decades, dengue virus has been a cause of major public health concern in Costa Rica, due to its landscape and climatic conditions that favor the circumstances in which the vector, Aedes aegypti, thrives. The emergence ...