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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 ... 
Deriving quantised inertia using horizonwidths in the uncertainty principle
(Hikari Ltd., 2020)In this paper we show that a model for inertial mass (quantised inertia) can be derived exactly and simply by assuming that the property of inertia is caused by gradients in the energy in the Unruh radiation field seen ... 
New results for the Mondrian art problem
(Elsevier, 2021)The Mondrian problem consists of dissecting a square of side length n ∈ N into noncongruent rectangles with natural length sides such that the difference d(n) between the largest and the smallest areas of the rectangles ... 
Using PRRSVresilient sows improve performance in endemic infected farms with recurrent outbreaks
(MDPI, 2021)The selection of porcine reproductive and respiratory syndrome (PRRS) resilient sows has been proposed as a strategy to control this disease. A discrete eventbased simulation model was developed to mimic the outcome of ... 
Orbital Reversibility of Planar Vector Fields
(MDPI, 2021)In this work we use the normal form theory to establish an algorithm to determine if a planar vector field is orbitally reversible. In previous works only algorithms to determine the reversibility and conjugate reversibility ... 
Directional analysis for point patterns on linear networks
(Wiley, 2020)Statistical analysis of point processes often assumes that the underlying process is isotropic in the sense that its distribution is invariant under rotation. For point processes on ℝ2, some tests based on the K‐ and nearest ... 
Contribuciones al perfeccionamiento del sistema de transporte terrestre en Cuba
(Academia de Ciencias de Cuba, 2020)Introducción. En el sistema de transporte de Cuba se presentan problemas que demandan respuestas adecuadas. Esta investigación en sus inicios estuvo dirigida al transporte de la caña en los centrales azucareros de la ... 
A general method to obtain the spectrum and local spectra of a graph from its regular partitions
(International Linear Algebra Society, 20200712)It is well known that, in general, part of the spectrum of a graph can be obtained from the adjacency matrix of its quotient graph given by a regular partition. In this paper, a method that gives all the spectrum, and also ... 
Modified inertia from extended uncertainty principle(s) and its relation to MoND
(Springer, 2020)In this paper we show that Modified Inertia, i.e., the modification of inertia predicted by some alternative theories of gravity at cosmic scales, can be naturally derived within the framework of the extended uncertainty ... 
Modified inertial mass from information loss
(World Scientific Publishing, 2017)A modification of inertia (called MiHsC or quantized inertia) has been proposed that assumes that inertia is caused by Unruh radiation, and that this radiation is made inhomogeneous in space by either Rindler horizons ... 
Numerical Simulation of NonLinear Models of Reaction—Diffusion for a DGT Sensor
(MDPI, 20200420)In this work, we present a novel strategy for the numerical solution of a coupled system of partial differential equations that describe reaction–diffusion processes of a mixture of metals and ligands that can be absorbed ... 
Notes sobre combinatòria: matemàtica discreta
(Paperkite Editorial, 2002)Aquestes notes pretenen ser una introducció a la Combinatòria Enumerativa, la qual s'ocupa dels problemes de recompte. Els continguts d'aquestes notes estan estructurats en dos capítols, un dedicat als principis, objectes ... 
A Construction for Providing Reusability to Mobile PhoneBased eTickets
(IEEE, 2020)Nowadays, the use of electronic tickets in public transport is a reality. Several mobile phonebased eticket systems have been proposed so far. Even so, very few of them include reusability in the sense that a single ... 
New MooreLike Bounds and Some Optimal Families of Abelian Cayley Mixed Graphs
(20200606)Mixed graphs can be seen as digraphs that have both arcs and edges (or digons, that is, two opposite arcs). In this paper, we consider the case where such graphs are Cayley graphs of abelian groups. Such groups can be ... 
Identifying codes in line digraphs
(Elsevier, 20200521)Given an integer ≥1, a (1, ≤ )identifying code in a digraph is a dominating subset C of vertices such that all distinct subsets of vertices of cardinality at most have distinct closed inneighborhoods within C . In ... 
An improved Moore bound and some new optimal families of mixed Abelian Cayley graphs
(Elsevier, 2020)We consider the case in which mixed graphs (with both directed and undirected edges) are Cayley graphs of Abelian groups. In this case, some Moore bounds were derived for the maximum number of vertices that such graphs can ...