Matemàtiques i Informàtica: Recent submissions
Now showing items 261-280 of 1007
Invariant manifolds of parabolic fixed points (II). Approximations by sums of homogeneous functions.
We study the computation of local approximations of invariant manifolds of parabolic fixed points and parabolic periodic orbits of periodic vector fields. If the dimension of these manifolds is two or greater, in general, ...
Data preparation for artificial intelligence in medical imaging: A comprehensive guide to open-access platforms and tools
The vast amount of data produced by today's medical imaging systems has led medical professionals to turn to novel technologies in order to efficiently handle their data and exploit the rich information present in them. ...
Fat-suppressed breast MRI synthesis for domain adaptation in tumour segmentation
Heterogeneity in dynamic contrast-enhanced breast MRI acquisition protocols hinders the generalization of automatic tumour segmentation tools. While fat-suppressed MRI acquisition is common, some vendors do not provide ...
A theorem on Schauder decompositions of Banach spaces
In this paper we prove that in a Banach space all Schauder decompositions are slirinking iff all Schauder decompositions are boundedly complete.
Extensions of maps defined on many fibres
Let S be a fibred surface. We prove that the existence of morphisms from non countably many fibres to curves implies, up to base change, the existence of a rational map from S to another surface fibred over the same base ...
High Performance Computing pp-distance algorithms to generate X-ray spectra from 3D models
X-ray crystallography is a powerful method that has significantly contributed to our understanding of the biological function of proteins and other molecules. This method relies on the production of crystals that, however, ...
Fourier frames
We solve the problem of Duffin and Schaeffer (1952) of characterizing those sequences of real frequencies which generate Fourier frames. Equivalently, we characterize the sampling sequences for the Paley-Wiener space. The ...
Xiao's conjecture for general fibred surfaces
We prove that the genus $g$, the relative irregularity $q_f$ and the Clifford index $c_f$ of a non-isotrivial fibration $f$ satisfy the inequality $q_f \leq g-c_f$. This gives in particular a proof of Xiao's conjecture for ...
Line search multilevel optimization as computational methods for dense optical flow
We evaluate the performance of different optimization techniques developed in the context of optical flow computation with different variational models. In particular, based on truncated Newton methods (TN) that have been ...
The impact of rare germline variants on human somatic mutation processes
Somatic mutations are an inevitable component of ageing and the most important cause of cancer. The rates and types of somatic mutation vary across individuals, but relatively few inherited influences on mutation processes ...
Encoding equivariant commutativity via operads
We prove a conjecture of Blumberg and Hill regarding the existence of $N_{\infty}$-operads associated to given sequences $\mathcal{F}=\left(\mathcal{F}_n\right)_{n \in \mathbb{N}}$ of families of subgroups of $G \times ...
On the relative value of weak information of supervision for learning generative models: An empirical study
Weakly supervised learning is aimed to learn predictive models from partially supervised data, an easy-to-collect alternative to the costly standard full supervision. During the last decade, the research community has ...
In-vivo Measurement of Wrist Movements During the Dart-Throwing Motion Using Inertial Measurement Units
Background: This study investigates the dart-throwing motion (DTM) by comparing an inertial measurement unit-based system previously validated for basic motion tasks with an optoelectronic motion capture system. The DTM ...
Remarks on Strongly modular jacobian surfaces
In [3] we introduced the concept of strongly modular abelian variety. This note contains some remarks and examples of this kind of varieties, especially for the case of Jacobian surfaces, that complement the results of
Càlculs en xarxes elèctriques
Les xarxes elèctriques subministren als seus usuaris energia elèctrica generada en centrals nuclears, hidroelèctriques, tèrmiques, eòliques... Aquestes xarxes són controlades per les companyies elèctriques mitjancant ...
A unified approach for the multivariate analysis of contingency tables
We present a unified approach to describing and linking several methods for representing categorical data in a contingency table. These methods include: correspondence analysis, Hellinger distance analysis, the log-ratio ...
Interpolation and Sampling Hypersurfaces for the Bargmann-Fock space in higher dimensions
We study those smooth complex hypersurfaces $W$ in $\C ^n$ having the property that all holomorphic functions of finite weighted $L^p$ norm on $W$ extend to entire functions with finite weighted $L^p$ norm. Such hypersurfaces ...
Instanton bundles on the flag variety $F(0,1,2)$
Instanton bundles on $\mathbb{P}^3$ have been at the core of the research in A1gebraic Geometry during the last thirty years. Motivated by the recent extension of their definition to other Fano threefolds of Picard number ...
Mixed dynamics of two-dimensional reversible maps with a symmetric couple of quadratic homoclinic tangencies
We study dynamics and bifurcations of 2-dimensional reversible maps having a symmetric saddle fixed point with an asymmetric pair of nontransversal homoclinic orbits (a symmetric nontransversal homoclinic figure-8). We ...
Polygonal cycles in higher Chow groups of Jacobians
The aim of this paper is to construct non-trivial cycles in the first higher Chow group of the Jacobian of a curve having special torsion points. The basic tool is to compute the analogue of the Griffiths' infinitesimal ...
