Searching Arxiv, refresh for possibly better results.

Results for "Jose-Raul Ruiz-Sarmiento"

total 9698took 0.13s
Automatic Multi-Sensor Extrinsic Calibration for Mobile RobotsJun 11 2019In order to fuse measurements from multiple sensors mounted on a mobile robot, it is needed to express them in a common reference system through their relative spatial transformations. In this paper, we present a method to estimate the full 6DoF extrinsic ... More
A host of traveling waves in a model of three-dimensional water-wave dynamicsNov 20 2001We describe traveling waves in a basic model for three-dimensional water-wave dynamics in the weakly nonlinear long-wave regime. Small solutions that are periodic in the direction of translation (or orthogonal to it) form an infinite-dimensional family. ... More
On manifolds supporting quasi Anosov diffeomorphismsOct 11 2001Let $M$ be an $n$-dimensional manifold supporting a quasi Anosov diffeomorphism. If $n=3$ then either $M={\mathbb T}^3$, in which case the diffeomorphisms is Anosov, or else its fundamental group contains a copy of ${\mathbb Z} ^6$. If $n=4$ then $\Pi_1(M)$ ... More
On the minimum orbital intersection distance computation: a new effective methodJun 21 2018The computation of the Minimum Orbital Intersection Distance (MOID) is an old, but increasingly relevant problem. Fast and precise methods for MOID computation are needed to select potentially hazardous asteroids from a large catalogue. The same applies ... More
Distributed ReliefF based Feature Selection in SparkNov 01 2018Feature selection (FS) is a key research area in the machine learning and data mining fields, removing irrelevant and redundant features usually helps to reduce the effort required to process a dataset while maintaining or even improving the processing ... More
The length of the low-redshift standard rulerJul 18 2016Assuming the existence of standard rulers, standard candles and standard clocks, requiring only the cosmological principle, a metric theory of gravity, a smooth expansion history, and using state-of-the-art observations, we determine the length of the ... More
On power ideals of transversal matroids and their "parking functions"May 18 2018To a vector configuration one can associate a polynomial ideal generated by powers of linear forms, known as a power ideal, which exhibits many combinatorial features of the matroid underlying the configuration. In this note we observe that certain power ... More
Ultra broadband waveveguide coupler using an anisotropic sub-wavelength metamaterialJun 12 2016Jul 29 2016Multimode interference couplers are a fundamental building block in many integrated photonic systems, ranging from high-speed coherent receivers to quantum splitters. However, their basic structure has remained fundamentally unchanged for almost four ... More
Admissible Lichnerowicz coordinates for the Schwarzschild metricSep 10 2001Jan 21 2002Global harmonic coordinates for the complete Schwarzschild metric are found for a more general case than that addressed in a previous work by Quan-Hui Liu. The supplementary constant that appears, in addition to the mass, is related to the stress quadrupole ... More
Fitting and selecting scattering dataNov 30 2017The main purpose of scattering experiments is to unveil the underlying structure of the colliding particles and their interaction. Typically one measures scattering observables (cross sections and polarizations) at discrete angles and energies and mutually ... More
Vector Boson Fusion in the Inert Doublet ModelSep 28 2017Mar 13 2018In this paper we probe inert Higgs doublet model at the LHC using Vector Boson Fusion (VBF) search strategy. We optimize the selection cuts and investigate the parameter space of the model and we show that the VBF search has a better reach when compared ... More
The Unruh effect without thermalityApr 02 2018We show that uniformly accelerated detectors can display genuinely thermal features even if the Kubo-Martin-Schwinger (KMS) condition fails to hold. These features include satisfying thermal detailed balance and having a Planckian response identical to ... More
Distributed Correlation-Based Feature Selection in SparkJan 31 2019CFS (Correlation-Based Feature Selection) is an FS algorithm that has been successfully applied to classification problems in many domains. We describe Distributed CFS (DiCFS) as a completely redesigned, scalable, parallel and distributed version of the ... More
Millimeter Wave Dual-Band Multi-Beam Waveguide Lens-Based AntennaMar 18 2018A multi-beam antenna with a dual band operation in the 28 GHz and 31 GHz millimeter wave band is presented. The antenna has a gain of around 15 dBi in each of the three ports. The spatial footprint of the antenna is 166 mm x 123 mm x 34 mm. A waveguide ... More
Scalar dark matter and fermion coannihilations in the radiative seesaw modelFeb 21 2013Feb 22 2013By extending the Standard Model with three right-handed neutrinos (N_i) and a second Higgs doublet (H_2), odd under a Z_2 symmetry, it is possible to explain non-zero neutrino masses and to account for the dark matter. We consider the case where the dark ... More
Lepton number violation in $B_s$ meson decays induced by an on-shell Majorana neutrinoAug 02 2017Apr 16 2018Lepton-number violation can be induced by the exchange of an on-shell Majorana neutrino $N$ in semileptonic $|\Delta L|=2$ decays of the $B_s$ meson, $B_s^0 \to P^-\pi^-\mu^+ \mu^+$ with $P=K, D_s$. We investigate the production of such a heavy sterile ... More
Exploring GeV-scale Majorana neutrinos in lepton-number-violating $Λ_b^0$ baryon decaysMay 26 2017Aug 01 2017In this work, the lepton-number-violating processes in $|\Delta L|=2$ decays of $\Lambda_b^0$ baryon, $\Lambda_b^0 \to p \pi^+\mu^- \mu^-$ and $\Lambda_b^0 \to \Lambda_c^+ \pi^+\mu^- \mu^-$, are investigated for the first time, via an intermediate on-shell ... More
Integrability of Stochastic Birth-Death processes via Differential Galois TheoryJan 18 2019Stochastic birth-death processes are described as continuous-time Markov processes in models of population dynamics. A system of infinite, coupled ordinary differential equations (the so-called master equation) describes the time-dependence of the probability ... More
Half-integer order Bessel beamsMay 30 2014Feb 21 2015Optical beams are solutions to the paraxial wave equation (PWE). In this work we report a new, to our knowledge, optical beam. We solve the PWE by using the angular spectrum of plane waves theory in circular cylindrical coordinates. This lead us to solutions ... More
Ultra-fast control of magnetic relaxation in a periodically driven Hubbard modelJan 15 2017Oct 23 2017Motivated by cold atom and ultra-fast pump-probe experiments we study the melting of long-range antiferromagnetic order of a perfect N\'eel state in a periodically driven repulsive Hubbard model. The dynamics is calculated for a Bethe lattice in infinite ... More
Superoutburst of WZ Sge-type Dwarf Nova Below the Period Minimum: ASASSN-15poOct 17 2016We report on a superoutburst of a WZ Sge-type dwarf nova (DN), ASASSN-15po. The light curve showed the main superoutburst and multiple rebrightenings. In this outburst, we observed early superhumps and growing (stage A) superhumps with periods of 0.050454(2) ... More
Long-term optical polarization variability and multiwavelength analysis of Blazar Mrk 421Jul 18 2017The results of 8-year R-band photopolarimetric data of blazar Mrk 421 collected from February 2008 to May 2016 are presented, along with extensive multiwavelength observations covering from radio to TeV $\gamma$-rays around the flares observed in May ... More
The kernel of chromatic quasisymmetric functions on graphs and nestohedraMar 23 2018Apr 05 2018We study the chromatic symmetric function on graphs, and show that its kernel is spanned by the modular relations. We generalise this result to the chromatic quasisymmetric function on nestohedra, a family of generalised permutahedra. We use this description ... More
Real Structures on Marked Schottky SpaceMar 14 2017Schottky groups are exactly those Kleinian groups providing the regular lowest planar uniformizations of closed Riemann surfaces and also the ones providing to the interior of a handlebody of a complete hyperbolic structure with injectivity radius bounded ... More
Kalai orientations on matroid polytopesApr 15 2005Let P a polytope and let G(P) be the graph of P. Following Gil Kalai, we say that an acyclic orientation O of G(P) is good if, for every non-empty face F of P, the induced graph G(F) has exactly one sink. Gil Kalai gave a simple way to tell a simple polytope ... More
ESASky : A Science-Driven Discovery Portal for Space-Based Astronomy MissionsNov 26 2018In the era of "big data" and with the advent of web 2.0 technologies, ESASky (http://sky.esa.int) aims at providing a modern and visual way to access astronomical science-ready data products and metadata. The main goal of the application is to simplify ... More
Millimagnitude Optical Photometry for the Transiting Planetary Candidate OGLE-TR-109Apr 12 2006Apr 14 2006We present precise V-band photometry for the low-amplitude transit candidate star OGLE-TR-109. This is an extreme case among the transiting candidates found by the OGLE group because of the early spectral type of the star (F0V), of the low transit amplitude ... More
Electrostatic Performance of InSb, GaSb, Si and Ge p-channel NanowiresApr 25 2017The electrostatic performance of p-type nanowires (NWs) made of InSb and GaSb, with special focus on their gate capacitance behavior, is analyzed and compared to that achieved by traditional semiconductors usually employed for p-MOS such as Si and Ge. ... More
Numerical solution of Mathisson-Papapetrou-Dixon equations for spinning test particles in a Kerr metricDec 04 2017Apr 07 2018In this work we calculate some estimations of the gravitomagnetic clock effect, taking into consideration not only the rotating gravitational field of the central mass, but also the spin of the test particle, obtaining values for $\Delta t=t_{+}-t_{-}=2.5212079035\times10^{-8} ... More
Vardøhus Codes: Polar Codes Based on Castle Curves KernelsJan 21 2019In this paper, we show some applications of algebraic curves to the construction of kernels of polar codes over a discrete memoryless channel which is symmetric w.r.t the field operations. We will also study the minimum distance of the polar codes proposed, ... More
Isotropic systems and the interlace polynomialJun 26 2006Jul 07 2006Through a series of papers in the 1980's, Bouchet introduced isotropic systems and the Tutte-Martin polynomial of an isotropic system. Then, Arratia, Bollob\'as, and Sorkin developed the interlace polynomial of a graph in [ABS00] in response to a DNA ... More
Geometry of $ν$-Tamari lattices in types $A$ and $B$Nov 29 2016Oct 10 2017In this paper, we exploit the combinatorics and geometry of triangulations of products of simplices to derive new results in the context of Catalan combinatorics of $\nu$-Tamari lattices. In our framework, the main role of "Catalan objects" is played ... More
Distance Hereditary Graphs and the Interlace PolynomialApr 04 2006Apr 14 2006The vertex-nullity interlace polynomial of a graph, described by Arratia, Bollob\'as and Sorkin as evolving from questions of DNA sequencing, and extended to a two-variable interlace polynomial by the same authors, evokes many open questions. These include ... More
Dyck path triangulations and extendabilityFeb 20 2014We introduce the Dyck path triangulation of the cartesian product of two simplices $\Delta_{n-1}\times\Delta_{n-1}$. The maximal simplices of this triangulation are given by Dyck paths, and its construction naturally generalizes to produce triangulations ... More
The $ν$-Tamari lattice as the rotation lattice of $ν$-treesMay 09 2018We give a new interpretation of the $\nu$-Tamari lattice of Pr\'eville-Ratelle and Viennot in terms of a rotation lattice of $\nu$-trees. This uncovers the relation with known combinatorial objects such as north-east fillings, tree-like tableaux and subword ... More
Parity binomial edge idealsMar 02 2015Feb 14 2017Parity binomial edge ideals of simple undirected graphs are introduced. Unlike binomial edge ideals, they do not have square-free Gr\"obner bases and are radical if only if the graph is bipartite or the characteristic of the ground field is not two. The ... More
UV/IR mixing and the Goldstone theorem in noncommutative field theoryFeb 01 2002May 27 2002Noncommutative IR singularities and UV/IR mixing in relation with the Goldstone theorem for complex scalar field theory are investigated. The classical model has two coupling constants, $\lambda_1$ and $\lambda_2$, associated to the two noncommutative ... More
High Responsivity and Quantum Efficiency of Graphene / Silicon Photodiodes Achieved by Interdigitating Schottky and Gated RegionsJul 13 2018Graphene / silicon (G/Si) heterostructures have been studied extensively in the past years for applications such as photodiodes, photodetectors and solar cells, with a growing focus on efficiency and performance. Here, a specific contact pattern scheme ... More
Dilaton tadpoles and D-brane interactions in compact spacesJul 19 2002Dec 02 2002We analyse some physical consequences when supersymmetry is broken by a set of D-branes and/or orientifold planes in Type II string theories. Generically, there are global dilaton tadpoles at the disk level when the transverse space is compact. By taking ... More
Insights into the robustness of control point configurations for homography and planar pose estimationMar 08 2018Jan 09 2019In this paper, we investigate the influence of the spatial configuration of a number of $n \geq 4$ control points on the accuracy and robustness of space resection methods, e.g. used by a fiducial marker for pose estimation. We find robust configurations ... More
Dynamic Markers: UAV landing proof of conceptSep 14 2017Jan 09 2019In this paper, we introduce a dynamic fiducial marker which can change its appearance according to the spatiotemporal requirements of the visual perception task of a mobile robot using a camera as the sensor. We present a control scheme to dynamically ... More
Pricing of Warrants with Stock Price Dependent Threshold ConditionsMar 17 2015Warrants with stock price dependent threshold conditions give the right to buy specially issued stocks, if the performance of the stock price satisfies some requirements. Existence of these derivatives changes the price process of the underlying. We show ... More
T35: a small automatic telescope for long-term observing campaignsFeb 18 2010The T35 is a small telescope (14") equipped with a large format CCD camera installed in the Sierra Nevada Observatory (SNO) in Southern Spain. This telescope will be a useful tool for the detecting and studying pulsating stars, particularly, in open clusters. ... More
Millimagnitude Photometry for Transiting Extrasolar Planetary Candidates IV: The Puzzle of the Extremely Red OGLE-TR-82 Primary SolvedJul 09 2007We present precise new V, I, and K-band photometry for the planetary transit candidate star OGLE-TR-82. Good seeing V-band images acquired with VIMOS instrument at ESO VLT allowed us to measure V=20.6+-0.03 mag star in spite of the presence of a brighter ... More
When is hyponormality for 2-variable weighted shifts invariant under powers?Apr 18 2011For 2-variable weighted shifts W_{(\alpha,\beta)}(T_1, T_2) we study the invariance of (joint) k- hyponormality under the action (h,\ell) -> W_{(\alpha,\beta)}^{(h,\ell)}(T_1, T_2):=(T_1^k,T_2^{\ell}) (h,\ell >=1). We show that for every k >= 1 there ... More
Jointly hyponormal pairs of commuting subnormal operators need not be jointly subnormalMay 30 2004We construct three different families of commuting pairs of subnormal operators, jointly hyponormal but not admitting commuting normal extensions. Each such family can be used to answer in the negative a 1988 conjecture of R. Curto, P. Muhly and J. Xia. ... More
A note on Tutte polynomials and Orlik-Solomon algebrasMar 15 2002Jul 30 2003Let A be a (central) arrangement of hyperplanes in a finite dimension complex vector space V. Let M(A) be the dependence matroid determined by A. The Orlik-Solomon algebra OS(M) of a matroid M is the exterior algebra on the points modulo the ideal generated ... More
Arithmeticity of totally geodesic Lie foliations with locally symmetric leavesJan 08 2007R. Zimmer proved that, on a compact manifold, a foliation with a dense leaf, a suitable leafwise Riemannian symmetric metric and a transverse Lie structure has arithmetic holonomy group. In this work we improve such result for totally geodesic foliations ... More
Topological Data Analysis of Single-cell Hi-C Contact MapsDec 04 2018In this article, we show how the recent statistical techniques developed in Topological Data Analysis for the Mapper algorithm can be extended and leveraged to formally define and statistically quantify the presence of topological structures coming from ... More
El Triangulo de Platon y El Factor Gnomonico: Una aplicacion a los oraculos de HerodotoMay 24 2013A modification to the gnomonic factor using the concept of triangle of Plato is presented. With the aid of the platonic gnomonic factor (fgp) as we called it, we find that the oracles mentioned by Herodotus in his History, Dodona in Greece and Ammon in ... More
Diagonal bases in Orlik-Solomon type algebrasJan 18 2002Jul 09 2003To encode an important property of the "no broken circuit bases" of the Orlik-Solomon-Terao algebras, Andras Szenes has introduced a particular type of bases, the so called "diagonal basis". We prove that this definition extends naturally to a large class ... More
A nonlinear discrete-velocity relaxation model for traffic flowOct 17 2017We derive a nonlinear 2-equation discrete-velocity model for traffic flow from a continuous kinetic model. The model converges to scalar Lighthill-Whitham type equations in the relaxation limit for all ranges of traffic data. Moreover, the model has an ... More
Separately Radial and Radial Toeplitz Operators on the Unit Ball and Representation TheorySep 23 2015Jan 26 2016We study Toeplitz operators with separately radial and radial symbols on the weighted Bergman spaces on the unit ball. The unitary equivalence of such operators with multiplication operators on $\ell^2$ spaces was previously obtained by analytic methods ... More
Isometric actions of simple groups and transverse structures: The integrable normal caseMar 09 2010For actions with a dense orbit of a connected noncompact simple Lie group $G$, we obtain some global rigidity results when the actions preserve certain geometric structures. In particular, we prove that for a $G$-action to be equivalent to one on a space ... More
Towards Automatic Global Error Control: Computable Weak Error Expansion for the Tau-Leap MethodApr 17 2010Dec 02 2010This work develops novel error expansions with computable leading order terms for the global weak error in the tau-leap discretization of pure jump processes arising in kinetic Monte Carlo models. Accurate computable a posteriori error approximations ... More
Kinetic layers and coupling conditions for nonlinear scalar equations on networksJan 01 2018We consider a kinetic relaxation model and an associated macroscopic scalar nonlinear hyperbolic equation on a network. Coupling conditions for the macroscopic equations are derived from the kinetic coupling conditions via an asymptotic analysis near ... More
Quadratic Orlik-Solomon algebras of graphic matroidsJun 15 2001Jan 08 2003In this note we introduce a sufficient condition for the Orlik-Solomon algebra associated to a matroid M to be l-adic and we prove that this condition is necessary when M is binary (in particular graphic). Moreover, this result cannot be extended to the ... More
Groebner and diagonal bases in Orlik-Solomon type algebrasJun 11 2001Oct 07 2003The Orlik-Solomon algebra of a matroid M is the quotient of the exterior algebra on the points by the ideal I(M) generated by the boundaries of the circuits of the matroid. There is an isomorphism between the Orlik-Solomon algebra of a complex matroid ... More
On the vanishing ideal of an algebraic toric set and its parameterized linear codesJul 21 2011Sep 16 2011Let K be a finite field and let X be a subset of a projective space, over the field K, which is parameterized by monomials arising from the edges of a clutter. We show some estimates for the degree-complexity, with respect to the revlex order, of the ... More
The second generalized Hamming weight of some evaluation codes arising from a projective torusNov 19 2016May 15 2018In this paper we find the second generalized Hamming weight of some evaluation codes arising from a projective torus, and it allows to compute the second generalized Hamming weight of the codes parameterized by the edges of any complete bipartite graph. ... More
On some consequences of the permutation paradigm for data anonymization: centrality of permutation matrices, universal measures of disclosure risk and information loss, evaluation by dominanceJan 29 2017Recently, the permutation paradigm has been proposed in data anonymization to describe any micro data masking method as permutation, paving the way for performing meaningful analytical comparisons of methods, something that is difficult currently in statistical ... More
Vanishing Ideals Of Affine Sets Parameterized By Odd CyclesOct 31 2017Let K be a finite field. Let X* be a subset of the affine space Kn, which is parameterized by odd cycles. In this paper we give an explicit Gr\"obner basis for the vanishing ideal, I(X*), of X*. We give an explicit formula for the regularity of I(X*) ... More
Geometric construction of D-branes in WZW modelsApr 25 2011Sep 02 2011The geometric description of D-branes in WZW models is pushed forward. Our starting point is a gluing condition\, $J_{+}=FJ_-$ that matches the model's chiral currents at the worldsheet boundary through a linear map $F$ acting on the WZW Lie algebra. ... More
Seiberg--Witten maps for $\boldsymbol{SO(1,3)}$ gauge invariance and deformations of gravityAug 14 2008Dec 12 2008A family of diffeomorphism-invariant Seiberg--Witten deformations of gravity is constructed. In a first step Seiberg--Witten maps for an SO(1,3) gauge symmetry are obtained for constant deformation parameters. This includes maps for the vierbein, the ... More
On the Schrodinger-Poisson-Slater system: behavior of minimizers, radial and nonradial casesApr 19 2009This paper is motivated by the study of a version of the so-called Schrodinger-Poisson-Slater problem: $$ - \Delta u + \omega u + \lambda (u^2 \star \frac{1}{|x|}) u=|u|^{p-2}u,$$ where $u \in H^1(\R^3)$. We are concerned mostly with $p \in (2,3)$. The ... More
A general cipher for individual data anonymizationDec 07 2017Over the years, the literature on individual data anonymization has burgeoned in many directions. Borrowing from several areas of other sciences, the current diversity of concepts, models and tools available contributes to understanding and fostering ... More
A multiplicative masking method for preserving the skewness of the original micro-recordsDec 07 2017Masking methods for the safe dissemination of microdata consist of distorting the original data while preserving a pre-defined set of statistical properties in the microdata. For continuous variables, available methodologies rely essentially on matrix ... More
The minimum distance of parameterized codes on projective toriSep 25 2010Jul 21 2011Let X be a subset of a projective space, over a finite field K, which is parameterized by the monomials arising from the edges of a clutter. Let I(X) be the vanishing ideal of X. It is shown that I(X) is a complete intersection if and only if X is a projective ... More
A note on mixed graphs and matroidsOct 06 2003A mixed graph is a graph with some directed edges and some undirected edges. We introduce the notion of mixed matroids as a generalization of mixed graphs. A mixed matroid can be viewed as an oriented matroid in which the signs over a fixed subset of ... More
The Division Algorithm in Sextic Truncated Moment ProblemsNov 26 2016For a degree 2n finite sequence of real numbers $\beta \equiv \beta^{(2n)}= \{ \beta_{00},\beta_{10}, \beta_{01},\cdots, \beta_{2n,0}, \beta_{2n-1,1},\cdots, \beta_{1,2n-1},\beta_{0,2n} \}$ to have a representing measure $\mu $, it is necessary for the ... More
Local theta lifting of generalized Whittaker models associated to nilpotent orbitsFeb 15 2013Aug 28 2013Let $(G,\tilde{G})$ be a reductive dual pair over a local field ${\Fontauri k}$ of characteristic 0, and denote by $V$ and $\tilde{V}$ the standard modules of $G$ and $\tilde{G}$, respectively. Consider the set $Max Hom(V,\tilde{V})$ of full rank elements ... More
On low-dimensional manifolds with isometric $\widetilde{\mathrm{U}}(p,q)$-actionsMar 04 2015Denote by $\widetilde{\mathrm{U}}(p,q)$ the universal covering group of $\mathrm{U}(p,q)$, the linear group of isometries of the pseudo-Hermitian space $\mathbb{C}^{p,q}$ of signature $p,q$. Let $M$ be a connected analytic complete pseudo-Riemannian manifold ... More
Bayesian Optimization of Composite FunctionsJun 04 2019We consider optimization of composite objective functions, i.e., of the form $f(x)=g(h(x))$, where $h$ is a black-box derivative-free expensive-to-evaluate function with vector-valued outputs, and $g$ is a cheap-to-evaluate real-valued function. While ... More
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. VII: The Seventh Year (2014-2015)Jul 20 2015Continuing the project described by Kato et al. (2009, arXiv:0905.1757), we collected times of superhump maxima for 102 SU UMa-type dwarf novae observed mainly during the 2014-2015 season and characterized these objects. Our project has greatly improved ... More
Propagation phenomena for hyponormal 2-variable weighted shiftsOct 28 2006We study the class of hyponormal 2-variable weighted shifts with two consecutive equal weights in the weight sequence of one of the coordinate operators. We show that under natural assumptions on the coordinate operators, the presence of consecutive equal ... More
Memory effects in measure transport equationsJun 27 2018Apr 15 2019Transport equations with a nonlocal velocity field have been introduced as a continuum model for interacting particle systems arising in physics, chemistry and biology. Fractional time derivatives, given by convolution integrals of the time-derivative ... More
Unbiased diffusion of Brownian particles on disordered correlated potentialsMar 18 2015In this work we study the diffusion of non-interacting overdamped particles, moving on unbiased disordered correlated potentials, subjected to Gaussian white noise. We obtain an exact expression for the diffusion coefficient which allows us to prove that ... More
The Pentagram map on GrassmanniansJul 16 2015In this paper we define a generalization of the pentagram map to a map on twisted polygons in the Grassmannian space Gr(n;mn). We define invariants of Grassmannian twisted polygons under the natural action of SL(nm), invariants that define coordinates ... More
Information geometry and asymptotic geodesics on the space of normal distributionsApr 29 2019The family $\mathcal{N}$ of $n$-variate normal distributions is parameterized by the cone of positive definite symmetric $n\times n$-matrices and the $n$-dimensional real vector space. Equipped with the Fisher information metric, $\mathcal{N}$ becomes ... More
Grow-up for a quasilinear heat equation with a localized reaction in higher dimensionsJan 29 2018We study the behaviour of nonnegative solutions to the quasilinear heat equation with a reaction localized in a ball $$ u_t=\Delta u^m+a(x)u^p, $$ for $m>0$, $0<p\le\max\{1,m\}$, $a(x)=\mathds{1}_{B_L}(x)$, $0<L<\infty$ and $N\ge2$. We study when solutions, ... More
Markov Approximations of Gibbs measures for long-range potentials on 1D latticesJun 25 2013We study one-dimensional lattice systems with pair-wise interactions of infinite range. We show projective convergence of Markov measures to the unique equilibrium state. For this purpose we impose a slightly stronger condition than summability of variations ... More
Mathematical analysis of the spreading of a rumor among different subgroups of spreadersJul 19 2016This paper presents a system of differential equations that describes the spreading of a rumor when it is propagated by different subgroups of spreaders. The system that is developed is a generalization of the model proposed by Daley and Kendall. Finally, ... More
On low-dimensional manifolds with isometric $\mathrm{SO}_0(p,q)$-actionsMar 02 2010Sep 27 2011Let $G$ be a non-compact simple Lie group with Lie algebra $\mathfrak{g}$. Denote with $m(\mathfrak{g})$ the dimension of the smallest non-trivial $\mathfrak{g}$-module with an invariant non-degenerate symmetric bilinear form. For an irreducible finite ... More
Freezing phase transition in a fractal potentialDec 29 2018In this work we propose a simple example of a one-dimensional thermodynamic system where non-interacting particles are allowed to move over the $[0,1]$ interval, which are influenced by a potential with a fractal structure. We prove that the system exhibits ... More
Non-extremal sextic moment problemsNov 26 2016Positive semidefiniteness, recursiveness, and the variety condition of a moment matrix are necessary and sufficient conditions to solve the quadratic and quartic moment problems. Also, positive semidefiniteness, combined with another necessary condition, ... More
Aluthge transforms of 2-variable weighted shiftsJun 11 2017We introduce two natural notions of multivariable Aluthge transforms (toral and spherical), and study their basic properties. In the case of 2-variable weighted shifts, we first prove that the toral Aluthge transform does not preserve (joint) hyponormality, ... More
Spectral pictures of 2-variable weighted shiftsOct 29 2006We study the spectral pictures of (jointly) hyponormal 2-variable weighted shifts with commuting subnormal components. By contrast with all known results in the theory of subnormal single and 2-variable weighted shifts, we show that the Taylor essential ... More
Grow-up for a quasilinear heat equation with a localized reactionJan 29 2018We study the behaviour of global solutions to the quasilinear heat equation with a reaction localized $$ u_t=(u^m)_{xx}+a(x) u^p, $$ $m, p>0$ and $a(x)$ being the characteristic function of an interval. we prove that there exists $p_0=\max\{1,\frac{m+1}2\}$ ... More
Termite: A System for Tunneling Through Heterogeneous DataMar 12 2019Data-driven analysis is important in virtually every modern organization. Yet, most data is underutilized because it remains locked in silos inside of organizations; large organizations have thousands of databases, and billions of files that are not integrated ... More
A time-fractional mean field gameSep 01 2017Jan 22 2018We consider a Mean Field Games model where the dynamics of the agents is subdiffusive. According to the optimal control interpretation of the problem, we get a system involving fractional time-derivatives for the Hamilton-Jacobi-Bellman and the Fokker-Planck ... More
Benchmark cool companions: Ages and abundances for the PZ Tel systemNov 29 2011Jan 26 2012We present new ages and abundance measurements for the pre-main sequence star PZ Tel. PZ Tel was recently found to host a young and low-mass companion. Using FEROS spectra we have measured atomic abundances (e.g. Fe and Li) and chromospheric activity ... More
The ALMA early science view of FUor/EXor objects - V: continuum disc masses and sizesNov 23 2017Low-mass stars build a significant fraction of their total mass during short outbursts of enhanced accretion known as FUor and EXor outbursts. FUor objects are characterized by a sudden brightening of ~5 magnitudes at visible wavelengths within one year ... More
Absolute Determination of the 22Na(p,g) Reaction Rate in NovaeSep 20 2010Feb 04 2011Gamma-ray telescopes in orbit around the Earth are searching for evidence of the elusive radionuclide 22Na produced in novae. Previously published uncertainties in the dominant destructive reaction, 22Na(p,g)23Mg, indicated new measurements in the proton ... More
Influence of Stoichiometry on the Optical and Electrical Properties of Chemical Vapor Deposition Derived MoS$_{2}$Sep 18 2014Ultrathin transition metal dichalcogenides (TMDCs) of Mo and W show great potential for digital electronics and optoelectronic applications. Whereas early studies were limited to mechanically exfoliated flakes, the large-area synthesis of 2D TMDCs has ... More
Imaging the water-snow line during a protostellar outburstJul 13 2016Jul 14 2016A snow-line is the region of a protoplanetary disk at which a major volatile, such as water or carbon monoxide, reaches its condensation temperature. Snow-lines play a crucial role in disk evolution by promoting the rapid growth of ice-covered grains. ... More
Enabling FAIR Research in Earth Science through Research ObjectsSep 27 2018Data-intensive science communities are progressively adopting FAIR practices that enhance the visibility of scientific breakthroughs and enable reuse. At the core of this movement, research objects contain and describe scientific information and resources ... More
Analysis of Muon Events in the DHCALFeb 29 2012Apr 13 2012The Digital Hadron Calorimeter (DHCAL) is a large prototype of an imaging calorimeter using Resistive Plate Chambers (RPCs) as active media. The readout is segmented into 1\times1 cm2 pads, each with a single bit resolution, hence the denomination of ... More
The Signature of a ManifoldAug 10 2005Jun 01 2015Let us consider a compact oriented riemannian manifold M without boundary and of dimension n=4k. The signature of M is defined as the signature of a given quadratic form Q. Two different products could be used to define Q and they render equivalent definitions: ... More
A notion of selective ultrafilter corresponding to topological Ramsey spacesOct 24 2005We introduce the relation of "almost-reduction" in an arbitrary topological Ramsey space R, as a generalization of the relation of "almost-inclusion" on the space of infinite sets of natural numbers (the Ellentuck space). This leads us to a type of ultrafilter ... More
The Fractal Geometry of the Cosmic Web and its FormationOct 04 2018Nov 29 2018The cosmic web structure is studied with the concepts and methods of fractal geometry, employing the adhesion model of cosmological dynamics as a basic reference. The structures of matter clusters and cosmic voids in N-body simulations or the Sloan Digital ... More