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Analytic integrability of certain resonant saddle
(Elsevier, 2021)We provide sufficient conditions of analytic integrability for a family of planar differential system with a p : −q resonant saddle at the origin. The conditions are then shown to be necessary in several finite dimensional ... 
Center cyclicity for some nilpotent singularities including the Z2equivariant class
(World Scientific Publishing, 20211020)This work concerns with polynomial families of real planar vector fields having a monodromic nilpotent singularity. The families considered are those for which the centers are characterized by the existence of a formal ... 
A computational model approach to assess the effect of climate change on the growth and development of tadpoles
(Elsevier, 2021)All of the environmental conditions in nature act on an organism simultaneously. However, in experimental studies of the factors influencing metamorphosis, each factor needs to be examined individually in order to disentangle ... 
A Digital Cash Paradigm with Valued and NoValued eCoins
(MDPI, 2021)Digital cash is a form of money that is stored digitally. Its main advantage when compared to traditional credit or debit cards is the possibility of carrying out anonymous transactions. Diverse digital cash paradigms have ... 
On dFibonacci digraphs
(Institut Teknologi Bandung (ITB) IndonesiaIndonesian Combinatorial Society (InaCombS)GTA Research Group, University of Newcastle (Australia), 2021)The dFibonacci digraphs F(d, k), introduced here, have the number of vertices following some generalized Fibonaccilike sequences. They can be defined both as digraphs on alphabets and as iterated line digraphs. Here we ... 
Bipartite biregular Moore graphs
(Elsevier, 2021)A bipartite graph G=(V,E) with V=V1 U V2 is biregular if all the vertices of a stable set Vi have the same degree ri for i=1,2. In this paper, we give an improved new Moore bound for an infinite family of such graphs with ... 
Spectra and eigenspaces of arbitrary lifts of graphs
(Springer, 20210923)We describe, in a very explicit way, a method for determining the spectra and bases of all the corresponding eigenspaces of arbitrary lifts of graphs (regular or not). 
Center problem for generic degenerate vector fields
(Elsevier, 2022)We generalize the method of construction of an integrating factor for Abel differential equations, developed in Briskin et al. (1998), for any generic monodromic singularity. Here generic means that the vector field has ... 
Linearizability of planar polynomial Hamiltonian systems
(Elsevier, 2022)Isochronicity and linearizability of twodimensional polynomial Hamiltonian systems are revisited and new results are presented. We give a new computational procedure to obtain the necessary and sufficient conditions for ... 
Stochastic smoothing of point processes for wildlifevehicle collisions on road networks
(Springer, 2021)Wildlifevehicle collisions on road networks represent a natural problem between human populations and the environment, that affects wildlife management and raise a risk to the life and safety of car drivers. We propose ... 
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 ...