Articles publicats (Matemàtica): Recent submissions
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Modeling inertia through the interaction with quantum fluctuations
(Elsevier, 2021)The origin of inertia of macroscopic bodies has never been thoroughly elucidated. In this paper we provide a new explanation based on the following assumptions: (i) we can think of any body as being composed by resonant ... 
On the Laplacian spectra of token graphs
(Elsevier, 2021)We study the Laplacian spectrum of token graphs, also called symmetric powers of graphs. The ktoken graph Fk(G) of a graph G is the graph whose vertices are the ksubsets of vertices from G, two of which being adjacent ... 
A New Normal Form for Monodromic Nilpotent Singularities of Planar Vector Fields
(Springer, 2021)In this work, we present a new technique for solving the center problem for nilpotent singularities which consists of determining a new normal form conveniently adapted to study the center problem for this singularity. In ... 
Designing ecommerce supply chains: a stochastic facility–location approach
(Wiley, 201707)eCommerce activity has been increasing during recent years, and this trend is expected to continue in thenear future. eCommerce practices are subject to uncertainty conditions and high variability in customers’demands. ... 
Pirámides indexadas y disimilaridades piramidales
(Institut d'Estadística de Catalunya, 1995)En este trabajo se pretende una formalización de las bases matemáticas sobre las que se amparan los modelos de clasificación y representación piramidal, estableciéndose para ello una relación entre los conceptos de pirámide ... 
Empirical significance test of the goodnessoffit for some pyramidal clustering procedures
(Institut d'Estadística de Catalunya, 1995)Through a series of simulation tests by Monte Carlo methods, some aspects relating to the inference concerning pyramidal trees built by the maximum and minimum methods are considered. In this sense, the quantiles of the ... 
Modelling the SARSCOV2 outbreak: assessing the usefulness of protective measures to reduce the pandemic at population level
(Elsevier, 2021)A new bioinspired computational model was developed for the SARSCoV2 pandemic using the available epidemiological information, highresolution population density data, travel patterns, and the average number of contacts ... 
Distancebased topological polynomials associated with zerodivisor graphs
(Hindawi, 202105)Let R be a commutative ring with nonzero identity and let Z(R) be its set of zero divisors. The zerodivisor graph of R is the graph T(R) with vertex set V(T(R))=Z(R)*, where Z(R)*=Z(R)\{0} , and edge set E(T(R))={{x,y}:x·y=0} ... 
Center problem and νcyclicity of polynomial zeroHopf singularities with nonsingular rotation axis
(Elsevier, 20210602)We consider threedimensional polynomial families of vector fields parameterized by the admissible coefficients having a fixed zeroHopf equilibrium and a nonsingular rotation axis through it. We are interested in the ... 
Some remarks on global analytic planar vector fields possessing an invariant analytic set
(Taylor and Francis, 20210201)We study the problem of determining the canonical form that a planar analytic vector field in all the real plane can have in order to possess a given invariant analytic set. We determine some conditions that guarantee that ... 
Economic assessment of pig meat processing and cutting production by simulation
(Walter de Gruyter, 201904)This paper presents the development and adoption of a discrete event simulation model of a pig meatpacking plant located in Navarre (Spain). The simulation model was developed to represent all the tasks and pig meat cuts ... 
Minimum tree decompositions with a given tree as a factor
(Combinatorial Mathematics Society of Australasia, 2005)A tree decomposition of a graph G is a family of subtrees whose sets of edges partition the set of edges of G. In this paper we are interested in the structure of the trees involved in tree decompositions with the minimum ... 
Modeling of Vaccination and Contact Tracing as Tools to Control the COVID19 Outbreak in Spain
(MDPI, 2021)We developed an agentbased stochastic model, based on P Systems methodology, to decipher the effects of vaccination and contact tracing on the control of COVID19 outbreak at population level under different control ... 
Vanishing set of inverse Jacobi multipliers and attractor/repeller sets
(American Institute of Physics, 20210101)In this paper we study conditions under which the zeroset of the inverse Jacobi multiplier of a smooth vector field contains its attractor/repeller compact sets. The work generalizes previous results focusing on sink ... 
Decompositions of a rectangle into noncongruent rectangles of equal area
(Elsevier, 202106)In this paper, we deal with a simple geometric problem: Is it possible to partition a rectangle into k noncongruent rectangles of equal area? This problem is motivated by the socalled 'Mondrian art problem' that asks a ... 
Highest weak focus order for trigonometric Liénard equations
(Springer, 2020)Given a planar analytic differential equation with a critical point which is a weak focus of order k, it is well known that at most k limit cycles can bifurcate from it. Moreover, in case of analytic Liénard differential ... 
Higher Accuracy of Lung Ultrasound over Chest Xray for Early Diagnosis of COVID19 Pneumonia
(MDPI, 2021)Background: The COVID19 pandemic rapidly strained healthcare systems worldwide. The reference standard for diagnosis is a positive reverse transcription polymerase chain reaction (RTPCR) test, but results are not immediate ... 
Evaluation of Replacement Policies in Sow Farms Using ArenaTM Simulation Software
(Scientific Research Publishing Inc., 2014)This paper presents an application of the simulation of discrete events (SED) using ARENATM in the management of largescale breeding farms. The main objective of the simulation model is to find a policy of replacement, ... 
Prospective Primary School Teachers’ Attitudes towards Probability and its Teaching
(Modestum Publishing Ltd., 2020)Since probability is a new topic at the primary school level in many countries, many primary school teachers may consider themselves not well prepared or may not value the formative role of probability as a topic for their ...