Listar MAT_Articles por título
-
Ultrafilters and non-Cantor minimal sets in linearly ordered dynamical systems
Springer Verlag (2008)It is well known that infinite minimal sets for continuous functions on the interval are Cantor sets; that is, compact zero dimensional metrizable sets without isolated points. On the other hand, it was proved in Alcaraz ... -
Uncertainty quantification for random Hamiltonian systems by using polynomial expansions and geometric integrators
Elsevier (2021-07-22)Recent advances in the field of uncertainty quantification are based on achieving suitable functional representations of the solutions to random systems. This aims at improving the performance of Monte Carlo simulation, ... -
Uncertainty quantification for random parabolic equations with nonhomogeneous boundary conditions on a bounded domain via the approximation of the probability density function
John Wiley & Sons, Ltd. (2018-11-14)This paper deals with the randomized heat equation defined on a general bounded interval [L1, L2] and with nonhomogeneous boundary conditions. The solution is a stochastic process that can be related, via changes of variable, ... -
Uncountable products of determined groups need not be determined
Elsevier (2008)If H is a dense subgroup of G, we say that H determines G if their groups of characters are topologically isomorphic when equipped with the compact open topology. If every dense subgroup of G determines G, then we say that ... -
Unitary transformations depending on a small parameter
Royal Society, The (2012)We formulate a unitary perturbation theory for quantum mechanics inspired by the LieDeprit formulation of canonical transformations. The original Hamiltonian is converted into a solvable one by a transformation obtained ... -
Unsupervised classification of children’s bodies using currents
Springer Verlag (2018-06)Object classification according to their shape and size is of key importance in many scientific fields. This work focuses on the case where the size and shape of an object is characterized by a current. A current is a ... -
Use of microperimetry to evaluate hydroxychloroquine and chloroquine retinal toxicity
Elsevier (2013)To check the ability of microperimetry to detect early retinal damage in patients with rheumatism taking hydroxychloroquine (HCQ), chloroquine (CQ), or both, and to describe the microperimetric alterations attributable to ... -
Valoración del grado de resección de los macroadenomas hipofisarios en la resonancia magnética posquirúrgica inmediata
Elsevier (2018)Objetivo Comprobar si es posible determinar el grado de resección de macroadenomas hipofisarios en la resonancia magnética (RM) hipofisaria posquirúrgica inmediata. Material y métodos Se revisaron las RM hipofisarias ... -
Variability of PM10 in industrialized-urban areas. New coefficients to establish significant differences between sampling points
Elsevier (2018-03)One of the main problems that arise in the assessment of air quality in an area is to estimate the number of representative sampling points of each microenvironment within it. We present a new model that reduces the ... -
Variables that affect the environmental performance of small electrical and electronic equipment. Methodology and case study
Elsevier (2018-12)This paper provides a methodology to identify the variables that affect the environmental performance of the life cycle of small electrical and electronic equipment (EEE). Different environmental indicators were contemplated ... -
Volume growth and the Cheeger isoperimetric constant of submanifolds
arXiv.org (2011)We obtain an estimate of the Cheeger isoperimetric constant in terms of the volume growth for a properly immersed submanifold in a Riemannian manifold which possesses at least one pole and sectional curvature bounded from above . -
Volume inequalities for the i-th-convolution bodies
Elsevier (2015-04)We obtain a new extension of Rogers–Shephard inequality providing an upper bound for the volume of the sum of two convex bodies K and L. We also give lower bounds for the volume of the k-th limiting convolution body of two ... -
Wavelet-Based Entropy Measures to Characterize Two-Dimensional Fractional Brownian Fields
MDPI (2020-02-07)The aim of this work was to extend the results of Perez et al. (Physica A (2006), 365 (2), 282–288) to the two-dimensional (2D) fractional Brownian field. In particular, we defined Shannon entropy using the wavelet spectrum ... -
Weight-preserving isomorphisms between spaces of continuous functions: The scalar case
Elsevier (2016-01)Let F be a finite field (or discrete) and let A andBB be vector spaces of F-valued continuous functions defined on locally compact spaces X and Y , respectively. We look at the representation of linear bijections H:A⟶B ... -
Weighted composite likelihood-based tests for space-time separability of covariance functions
Springer US (2010)Testing for separability of space-time covariance functions is of great interest in the analysis of space-time data. In this paper we work in a parametric framework and consider the case when the parameter identifying the ... -
Well posedness for semidiscrete fractional Cauchy problems with finite delay
Elsevier (2017-08)We address the study of well posedness on Lebesgue spaces of sequences for the following fractional semidiscrete model with finite delay ∆ α u ( n ) = Tu ( n ) + β u ( n − τ ) + f ( n ) , n ∈ N , 0 < ... -
When a totally bounded group topology is the Bohr topology of a LCA group
Elsevier (2019-06-01)We look at the Bohr topology of maximally almost periodic groups (MAP, for short). Among other results, we investigate when a Hausdorff precompact abelian group (G; w) is the Bohr re ection of a locally compact abelian ... -
When the ground cover brings guests: is Anaphothrips obscurus a friend or a foe for the biological control of Tetranychus urticae in clementines?
Springer (2017-10)Biological control of Tetranychus urticae Koch (Acari: Tetranychidae), a key pest of clementines, can be improved in this crop with the establishment of a ground cover of Festuca arundinacea Schreber (Poaceae). This cover ... -
Which series are Hilbert series of graded modules over standard multigraded polynomial rings?
Wiley (2020)Consider a polynomial ring 𝑅� with the ℤ𝑛�-grading where the degree of each variableis a standard basis vector. In other words, 𝑅� is the homogeneous coordinate ring ofa product of 𝑛� projective spaces. In this setting, ... -
Written on stone: Engraved European medieval solar eclipses
Cambridge University Press (2019-12)In the context of the European Middle Ages as the period roughly covering from the 5th to the 15th centuries, the astronomical records are rarery found in scientific treatises. At least, not until the 15th century. A few ...