Results for "Hildebrando M. Rodrigues"

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An example on Lyapunov stability and linearizationFeb 06 2019The purpose of this paper is to present an example of a C1 (in the Fr\'echet sense) discrete dynamical system in a infinite-dimensional separable Hilbert space for which the origin is an exponentially asymptotically stable fixed point, but such that its ... More
Stability problems in non autonomous linear differential equations in infinite dimensionsJun 11 2019One goal of this paper is to study robustness of stability of nonautonomous linear ordinary differential equations under integrally small perturbations in an infinite dimensional Banach space. Some applications are obtained to the case of rapid oscillatory ... More
Generalized splines in R^n and optimal controlMay 11 2004Jun 14 2005We have found an inconsistency in our previous version of the paper "Generalized splines in R^n and optimal control". We give a new-time-dependent definition of spline curves in R^n which results from solving a non-autonomous linear quadratic optimal ... More
Switched graphs of some strongly regular graphs related to the symplectic graphMay 24 2016Applying a method of Godsil and McKay \cite{GM} to some graphs related to the symplectic graph, a series of new infinite families of strongly regular graphs with parameters $(2^n\pm2^{(n-1)/2},2^{n-1}\pm2^{(n-1)/2},2^{n-2}\pm2^{(n-3)/2},2^{n-2}\pm2^{(n-1)/2})$ ... More
Non-concave utility maximisation on the positive real axis in discrete timeJan 13 2015Apr 22 2015We treat a discrete-time asset allocation problem in an arbitrage-free, generically incomplete financial market, where the investor has a possibly non-concave utility function and wealth is restricted to remain non-negative. Under easily verifiable conditions, ... More
On client interactive behaviour to design peer selection policies for BitTorrent-like protocolsOct 08 2013Peer-to-peer swarming protocols have been proven to be very efficient for content replication over Internet. This fact has certainly motivated proposals to adapt these protocols to meet the requirements of on-demand streaming system. The vast majority ... More
Stability of periodic waves in Hamiltonian PDEs of either long wavelength or small amplitudeOct 11 2017Stability criteria have been derived and investigated in the last decades for many kinds of periodic traveling wave solutions to Hamiltonian PDEs. They turned out to depend in a crucial way on the negative signature of the Hessian matrix of action integrals ... More
Extensor in Geometric AlgebrasJan 31 2005Aug 30 2006This paper, the third in a series of eight introduces some of the basic concepts of the theory of extensors needed for our formulation of the differential geometry of smooth manifolds . Key notions such as the extension and generalization operators of ... More
Multivector Functions of a Multivector VariableDec 17 2002Dec 18 2002In this paper we develop with considerable details a theory of multivector functions of a $p$-vector variable. The concepts of limit, continuity and differentiability are rigorously studied. Several important types of derivatives for these multivector ... More
Geometric and Extensor Algebras and the Differential Geometry of Arbitrary ManifoldsMar 03 2007Nov 29 2007We give in this paper which is the third in a series of four a theory of covariant derivatives of representatives of multivector and extensor fields on an arbitrary open set U of M, based on the geometric and extensor calculus on an arbitrary smooth manifold ... More
Second Order Swarm IntelligenceJun 13 2013An artificial Ant Colony System (ACS) algorithm to solve general-purpose combinatorial Optimization Problems (COP) that extends previous AC models [21] by the inclusion of a negative pheromone, is here described. Several Travelling Salesman Problem (TSP) ... More
Fractional derivatives in Dengue epidemicsAug 08 2011We introduce the use of fractional calculus, i.e., the use of integrals and derivatives of non-integer (arbitrary) order, in epidemiology. The proposed approach is illustrated with an outbreak of dengue disease, which is motivated by the first dengue ... More
Banking risk as an epidemiological model: an optimal control approachJul 11 2017The process of contagiousness spread modelling is well-known in epidemiology. However, the application of spread modelling to banking market is quite recent. In this work, we present a system of ordinary differential equations, simulating data from the ... More
Weighted Alexandrov-Fenchel inequalities in hyperbolic space and a conjecture of Ge, Wang and WuFeb 19 2019Jun 24 2019We consider a conjecture made by Ge, Wang and Wu regarding weighted Alexandrov-Fenchel inequalities for horospherically convex hypersurfaces in hyperbolic space (a bound, for some physically motivated weight function, of the weighted integral of the $k^{\mathrm{th}}$ ... More
Optimal control of a delayed HIV modelAug 21 2017We propose a model for the human immunodeficiency virus type 1 (HIV-1) infection with intracellular delay and prove the local asymptotical stability of the equilibrium points. Then we introduce a control function representing the efficiency of reverse ... More
Navier-Stokes Equation on the RectangleApr 15 2005We study controllability issues for the Navier-Stokes Equation on a two dimensional rectangle with so-called Lions boundary conditions. Rewriting the Equation using a basis of harmonic functions we arrive to an infinite-dimensional system of ODEs. Methods ... More
Homotopy Quantum Field Theories and the Homotopy Cobordism Category in Dimension 1+1May 02 2001Aug 14 2002We define Homotopy quantum field theories (HQFT) as Topological quantum field theories (TQFT) for manifolds endowed with extra structure in the form of a map into some background space X. We also build the category of homotopy cobordisms HCobord(n,X) ... More
Optimal control and numerical software: an overviewJan 28 2014Optimal Control (OC) is the process of determining control and state trajectories for a dynamic system, over a period of time, in order to optimize a given performance index. With the increasing of variables and complexity, OC problems can no longer be ... More
Time Scales and MathematicaNov 17 2009Time scales are a model of time, where the continuous and the discrete time cases are considered and merged into the same framework. In this paper some basic definitions of the time scale calculus are presented. Simultaneously, a package in Mathematica ... More
Sensitivity Analysis in a Dengue Epidemiological ModelJun 30 2013Epidemiological models may give some basic guidelines for public health practitioners, allowing to analyze issues that can influence the strategies to prevent and fight a disease. To be used in decision-making, however, a mathematical model must be carefully ... More
Control of dengue disease: a case study in Cape VerdeJun 30 2010A model for the transmission of dengue disease is presented. It consists of eight mutually-exclusive compartments representing the human and vector dynamics. It also includes a control parameter (adulticide spray) in order to combat the mosquito. The ... More
Dynamics of Dengue epidemics using optimal controlJun 22 2010We present an application of optimal control theory to Dengue epidemics. This epidemiologic disease is an important theme in tropical countries due to the growing number of infected individuals. The dynamic model is described by a set of nonlinear ordinary ... More
Monte Carlo Simulation and Experimental Characterization of a Dual Head Gamma CameraNov 16 2007The GEANT4 Monte Carlo simulation and experimental characterization of the Siemens E.Cam Dual Head gamma camera hosted in the Particular Hospital of Algarve have been done. Imaging tests of thyroid and other phantoms have been made "in situ" and compared ... More
Magnetic Phases and Specific Heat of Ultra-Thin Holmium FilmsMar 14 2014We report model calculations of the magnetic phases of very thin Ho films in the temperature interval between 20K and 132K, and show that slab size, surface effects and magnetic field due to spin ordering may impact significantly the magnetic phase diagram. ... More
Parallelism Structure on a Smooth ManifoldMar 18 2007Using the theory of extensors developed in a previous paper we present a theory of the parallelism structure on arbitrary smooth manifold. Two kinds of Cartan connection operators are introduced and both appear in intrinsic versions (i.e., frame independent) ... More
Short-term synaptic plasticity in the deterministic Tsodyks-Markram model leads to unpredictable network dynamicsSep 30 2013Short-Term Synaptic Plasticity (STSP) strongly affects the neural dynamics of cortical networks. The Tsodyks and Markram (TM) model for STSP accurately accounts for a wide range of physiological responses at different types of cortical synapses. Here, ... More
Holographic Description of Chiral Symmetry Breaking in a Magnetic Field in 2+1 Dimensions with an Improved DilatonNov 09 2018We consider a holographic description of the chiral symmetry breaking in an external magnetic field in $ (2+1) $-dimensional gauge theories from the softwall model using an improved dilaton field profile given by $\Phi(z) = - kz^2 + (k+k_1)z^2\tanh (k_{2}z^2)$. ... More
Finite Temperature behavior of the CPT-even and parity-even electrodynamics of the Standard Model ExtensionJul 10 2009Sep 06 2009In this work, we examine the finite temperature properties of the CPT-even and Lorentz-invariance-violating (LIV) electrodynamics of the standard model extension, represented by the term $W_{\alpha \nu \rho \phi}F^{\alpha \nu}F^{\rho \phi}$. We begin ... More
An Electromagnet-Based Magnetically-Activated Thermal Switch Without Moving PartsMar 28 2018With the ever increasing power dissipation in electrical devices, new thermal management solutions are in high demand to maintain an optimal operating temperature and efficient performance. In particular, recently developed magnetically-activated thermal ... More
Optical observations and cyclops post-shock region modelling of the polar V348 PavSep 02 2019Post-shock regions (PSR) of polar cataclysmic variables produce most of their luminosity and give rise to high circular polarization in optical wavelengths and strong variability on the white dwarf rotation period, which are distinctive features of these ... More
Production of H$_3^+$ via photodissociation of organic molecules in interstellar cloudsDec 14 2006We present experimental results obtained from photoionization and photodissociation processes of abundant interstellar CH$_3$-X type organic molecules like methanol (CH$_3$OH), methylamine (CH$_3$NH$_2$) and acetonitrile (CH$_3$CN) as alternative route ... More
The Wolf-Rayet features and mass-metallicity relation of long-duration gamma-ray burst host galaxiesJan 14 2010Jun 16 2010Aims. We have gathered optical spectra of 8 long-duration GRB host galaxies selected from the archival data of VLT/FORS2. We investigated whether or not Wolf-Rayet (WR) stars can be detected in these GRB host galaxies. We also tried to estimate the physical ... More
BULNER: BUg Localization with word embeddings and NEtwork RegularizationAug 26 2019Bug localization (BL) from the bug report is the strategic activity of the software maintaining process. Because BL is a costly and tedious activity, BL techniques information retrieval-based and machine learning-based could aid software engineers. We ... More
Can noncommutativity affect the whole history of the Universe?Sep 16 2011Feb 11 2016We study a classical, noncommutative (NC), Friedmann-Robertson-Walker cosmological model. The spatial sections may have positive, negative or zero constant curvatures. The matter content is a generic perfect fluid. The initial noncommutativity between ... More
Measurement of the absolute reflectance of polytetrafluoroethylene (PTFE) immersed in liquid xenonDec 23 2016The performance of a detector using liquid xenon (LXe) as a scintillator is strongly dependent on the collection efficiency for xenon scintillation light, which in turn is critically dependent on the reflectance of the surfaces that surround the active ... More
MIRA: A Computational Neuro-Based Cognitive Architecture Applied to Movie Recommender SystemsFeb 25 2019Feb 27 2019The human mind is still an unknown process of neuroscience in many aspects. Nevertheless, for decades the scientific community has proposed computational models that try to simulate their parts, specific applications, or their behavior in different situations. ... More
"Non-renormalization" without supersymmetryNov 03 2006Dec 19 2006The g_{YM} perturbed, non supersymmetric extension of the dual single matrix description of 1/2 BPS states, within the Hilbert space reduction to the oscillator subsector associated with chiral primaries is considered. This matrix model is described in ... More
Strange attractors and non wandering domains near a homoclinic cycle to a bifocusJan 11 2018Jun 06 2018In this paper, we explore the three-dimensional chaotic set near a homoclinic cycle to a hyperbolic bifocus at which the vector field has negative divergence. If the invariant manifolds of the bifocus satisfy a non-degeneracy condition, a sequence of ... More
Asymptotic stability of Oseen vortices for a density-dependent incompressible viscous fluidNov 20 2006In the analysis of the long-time behaviour of two-dimensional incompressible viscous fluids, Oseen vortices play a major role as attractors of any homogeneous solution with integrable initial vorticity. As a first step in the study of the density-dependent ... More
Existence of non-trivial embeddings of Interval Exchange Transformations into Piecewise IsometriesJan 29 2019We prove that almost every interval exchange transformation, with an associated translation surface of genus $g\geq 2$, can be non-trivially and isometrically embedded in a family of piecewise isometries. In particular this proves the existence of invariant ... More
On the Hydrogen Atom via Wigner-Heisenberg AlgebraDec 03 2008Aug 18 2009We extend the usual Kustaanheimo-Stiefel $4D\to 3D$ mapping to study and discuss a constrained super-Wigner oscillator in four dimensions. We show that the physical hydrogen atom is the system that emerges in the bosonic sector of the mapped super 3D ... More
Linear Asymptotic Stability and Modulation Behavior near Periodic Waves of the Korteweg-de Vries EquationJun 19 2017We provide a detailed study of the dynamics obtained by linearizing the Korteweg-de Vries equation about one of its periodic traveling waves, a cnoidal wave. In a suitable sense, linearly analogous to space-modulated stability, we prove global-in-time ... More
Attractors in complex networksSep 10 2017In the framework of the generalized Lotka Volterra model, solutions representing multispecies sequencial competition can be predictable with high probability. In this paper, we show that it occurs because the corresponding "heteroclinic channel" forms ... More
Large-time behavior of solutions to Vlasov-Poisson-Fokker-Planck equations: from evanescent collisions to diffusive limitJun 19 2017Nov 07 2017The present contribution investigates the dynamics generated by the two-dimensional Vlasov-Poisson-Fokker-Planck equation for charged particles in a steady inhomogeneous background of opposite charges. We provide global in time estimates that are uniform ... More
Sequence co-evolution gives 3D contacts and structures of protein complexesMay 05 2014Sep 16 2014Protein-protein interactions are fundamental to many biological processes. Experimental screens have identified tens of thousands of interactions and structural biology has provided detailed functional insight for select 3D protein complexes. An alternative ... More
Galactic Archaeology with CoRoT and APOGEE: Creating mock observations from a chemodynamical modelApr 26 2016In a companion paper, we have presented the combined asteroseismic-spectroscopic dataset obtained from CoRoT lightcurves and APOGEE infra-red spectra for 678 solar-like oscillating red giants in two fields of the Galactic disc (CoRoGEE). We have measured ... More
Rotational deviations and invariant pseudo-foliations for periodic point free torus homeomorphismsApr 16 2017Mar 11 2018This article deals with directional rotational deviations for non-wandering periodic point free homeomorphisms of the 2-torus which are homotopic to the identity. We prove that under mild assumptions, such a homeomorphism exhibits uniformly bounded rotational ... More
Increasing powers in a degenerate parabolic logistic equationJun 26 2012The purpose of this paper is to study the asymptotic behavior of the positive solutions of the problem $$ \partial_t u-\Delta u=a u-b(x) u^p \text{in} \Omega\times \R^+, u(0)=u_0, u(t)|_{\partial \Omega}=0 $$ as $p\to +\infty$, where $\Omega$ is a bounded ... More
Spatio-temporal Dynamics of Foot-and-Mouth Disease Virus in South AmericaMay 05 2015Jun 01 2015Although foot-and-mouth disease virus (FMDV) incidence has decreased in South America over the last years, the pathogen still circulates in the region and the risk of re-emergence in previously FMDV-free areas is a veterinary public health concern. In ... More
On the Two Obstacles Problem in Orlicz-Sobolev Spaces and ApplicationsMar 08 2010We prove the Lewy-Stampacchia inequalities for the two obstacles problem in abstract form for T-monotone operators. As a consequence for a general class of quasi-linear elliptic operators of Ladyzhenskaya-Uraltseva type, including p(x)-Laplacian type ... More
Stabilization to trajectories for parabolic equationsAug 08 2016Aug 24 2016The feedback exponential stabilization to trajectories for semilinear parabolic equations in a given bounded domain is addressed. The controls take values in a finite-dimensional space and are supported in a small region. Both internal and boundary controls ... More
Strong Electronic Interaction and Signatures of Nodal Superconductivity in Zr$_5$Pt$_3$C$_x$Sep 13 2018Jan 08 2019The physical properties of the Zr$_5$Pt$_3$ compound with interstitial carbon in hexagonal D8$_8$-structure was investigated. A set of macroscopic measurements reveal a bulk superconducting at approximately 7 K for Zr$_5$Pt$_3$C$_{0.3}$ close to Zr$_5$Pt$_3$, ... More
Complex Network Tools to Understand the Behavior of Criminality in Urban AreasDec 19 2016Dec 24 2016Complex networks are nowadays employed in several applications. Modeling urban street networks is one of them, and in particular to analyze criminal aspects of a city. Several research groups have focused on such application, but until now, there is a ... More
A biophysical observation model for field potentials of networks of leaky integrate-and-fire neuronsSep 03 2012Nov 21 2012We present a biophysical approach for the coupling of neural network activity as resulting from proper dipole currents of cortical pyramidal neurons to the electric field in extracellular fluid. Starting from a reduced threecompartment model of a single ... More
Coupling continuous neural networks to the electromagnetic field in nervous tissueJun 30 2010Sep 03 2012We present a microscopic approach for the coupling of cortical activity, as resulting from proper dipole currents of pyramidal neurons, to the electromagnetic field in extracellular fluid in presence of diffusion and Ohmic conduction. As a result, neural ... More
tsmp: An R Package for Time Series with Matrix ProfileApr 18 2019This article describes tsmp, an R package that implements the matrix profile concept for time series. The tsmp package is a toolkit that allows all-pairs similarity joins, motif, discords and chains discovery, semantic segmentation, etc. Here we describe ... More
On the explicit feedback stabilisation of 1D linear nonautonomous parabolic equations via oblique projectionsAug 03 2018In recently proposed stabilisation techniques for parabolic equations, a crucial role is played by a suitable sequence of oblique projections in Hilbert spaces, onto the linear span of a suitable set of M actuators, and along the subspace orthogonal to ... More
MLS110213:022733+130617: A new eclipsing polar above the period gapJan 30 2014We present new data that confirm MLS110213:022733+130617 as a new eclipsing polar. Some system properties were estimated.
The LDA-1/2 method applied to atoms and moleculesMay 24 2018The LDA-1/2 method has proven to be a viable approach for calculating band gaps of semiconductors. To address its accuracy for finite systems, we apply LDA-1/2 to atoms and the molecules of the $GW100$ test set. The obtained energies of the highest-occupied ... More
Critical behavior of the isotope yield distributions in the Multifragmentation Regime of Heavy Ion ReactionsJul 27 2010Isotope yields have been analyzed within the framework of a Modified Fisher Model to study the power law yield distribution of isotopes in the multifragmentation regime. Using the ratio of the mass dependent symmetry energy coefficient relative to the ... More
The Isospin Dependence Of The Nuclear Equation Of State Near The Critical PointFeb 09 2010We discuss experimental evidence for a nuclear phase transition driven by the different concentration of neutrons to protons. Different ratios of the neutron to proton concentrations lead to different critical points for the phase transition. This is ... More
On the existence of rotated $D_n$-lattices constructed via Galois extensionsJun 27 2012Nov 01 2012In this paper we construct families of rotated $D_n$-lattices which may be suitable for signal transmission over both Gaussian and Rayleigh fading channels via subfields of cyclotomic fields. These constructions exhibit full diversity and good minimum ... More
Comment on "Generic rotating regular black holes in general relativity coupled to non-linear electrodynamics"Dec 10 2017We show that there is an inconsistency in the class of solutions obtained in Phys. Rev. D {\bf 95}, 084037 (2017). This inconsistency is due to the approximate relation between lagrangian density and its derivative for Non-Linear Electrodynamics. We present ... More
Numerical Evolution of axisymmetric vacuum spacetimes: a code based on the Galerkin methodSep 17 2008Nov 10 2011We present the first numerical code based on the Galerkin and Collocation methods to integrate the field equations of the Bondi problem. The Galerkin method like all spectral methods provide high accuracy with moderate computational effort. Several numerical ... More
Thermodynamic behavior of binary mixtures of hard spheres: Semianalytical solutions on a Husimi lattice built with cubesAug 31 2019We study binary mixtures of hard particles, which exclude up to their $k$th nearest neighbors ($k$NN) on the simple cubic lattice and have activities $z_k$. In the first model analyzed, point particles (0NN) are mixed with 1NN ones. The grand-canonical ... More
Latent Sentiment Detection in Online Social Networks: A Communications-oriented ViewJan 09 2014In this paper, we consider the problem of latent sentiment detection in Online Social Networks such as Twitter. We demonstrate the benefits of using the underlying social network as an Ising prior to perform network aided sentiment detection. We show ... More
Topological entropy for partial actions of the group $\mathbb Z$Sep 20 2015Apr 14 2016In this paper we introduce the definition of entropy for a partial $\mathbb{Z}$-action. We show that the definition of partial entropy is an extension of the definition of topological entropy for a $\mathbb Z$-action. We also prove that the partial topological ... More
Systematic $1/N$ corrections for bosonic and fermionic vector models without auxiliary fieldsMay 10 1996Oct 19 1996In this paper, colorless bilocal fields are employed to study the large $N$ limit of both fermionic and bosonic vector models. The Jacobian associated with the change of variables from the original fields to the bilocals is computed exactly, thereby providing ... More
The Collective Field Theory of a Singular Supersymmetric Matrix ModelOct 03 1994Oct 31 1994The supersymmetric collective field theory with the potential $v'(x)=\omega x-{\eta\over x}$ is studied, motivated by the matrix model proposed by Jevicki and Yoneya to describe two dimensional string theory in a black hole background. Consistency with ... More
On a p-curl system arising in electromagnetismSep 02 2010We prove existence of solution of a $p$-curl type evolutionary system arising in electromagnetism with a power nonlinearity of order $p$, $1<p<\infty$, assuming natural tangential boundary conditions. We consider also the asymptotic behaviour in the power ... More
Bowen-Franks groups as conjugacy invariants for $\mathbb{T}^{n}$ automorphismsMar 15 2003The role of generalized Bowen-Franks groups (BF-groups) as topological conjugacy invariants for $\mathbb{T}^{n}$ automorphisms is studied. Using algebraic number theory, a link is established between equality of BF-groups for different automorphisms ($BF$-equivalence) ... More
Fair Measures for Countable-to-one MapsOct 16 2018In this paper we generalize the recently introduced concept of fair measure (M. Misiurewicz and A. Rodrigues, Counting preimages. Ergod. Th. & Dynam. Sys. 38 (2018), no. 5, 1837 -- 1856). We study transitive countable state Markov shift maps and extend ... More
Blobs in Wolf-Rayet Winds: Random Photometric and Polarimetric VariabilityMar 23 2000Some isolated Wolf-Rayet stars present random variability in their optical flux and polarization. We make the assumption that such variability is caused by the presence of regions of enhanced density, i.e. blobs, in their envelopes. In order to find the ... More
Vacuum Polarization of a Scalar Field in a Rectangular WaveguideNov 14 2001Sep 03 2002An analysis of the one-loop vacuum fluctuations associated with a scalar field confined in the interior of a infinite waveguide of rectangular cross section is presented. We first consider the massless scalar field defined in a four-dimensional Euclidean ... More
Multi-modal Image Processing based on Coupled Dictionary LearningJun 26 2018In real-world scenarios, many data processing problems often involve heterogeneous images associated with different imaging modalities. Since these multimodal images originate from the same phenomenon, it is realistic to assume that they share common ... More
Generalized Paxos Made Byzantine (and Less Complex)Aug 24 2017Oct 19 2017One of the most recent members of the Paxos family of protocols is Generalized Paxos. This variant of Paxos has the characteristic that it departs from the original specification of consensus, allowing for a weaker safety condition where different processes ... More
Representation of Markov chains by random maps: existence and regularity conditionsJul 20 2012Mar 16 2015We systematically investigate the problem of representing Markov chains by families of random maps, and which regularity of these maps can be achieved depending on the properties of the probability measures. Our key idea is to use techniques from optimal ... More
Partial symmetry breaking and heteroclinic tangenciesFeb 21 2013We study some global aspects of the bifurcation of an equivariant family of volume-contracting vector fields on the three-dimensional sphere. When part of the symmetry is broken, the vector fields exhibit Bykov cycles. Close to the symmetry, we investigate ... More
Fine-Grained Energy and Performance Profiling framework for Deep Convolutional Neural NetworksMar 29 2018May 14 2018There is a huge demand for on-device execution of deep learning algorithms on mobile and embedded platforms. These devices present constraints on the application due to limited resources and power. Hence, developing energy-efficient solutions to address ... More
Quantitative recurrence for free semigroup actionsDec 21 2016We consider finitely generated free semigroup actions on a compact metric space and obtain quantitative information on Poincar\'e recurrence, average first return time and hitting frequency for the random orbits induced by the semigroup action. Besides, ... More
Synthesis, characterization and magnetic properties of room-temperature nanofluid ferromagnetic graphiteDec 29 2009We report the chemical synthesis route, structural characterization, and physical properties of nanofluid magnetic graphite (NFMG) obtained from the previously synthesized bulk organic magnetic graphite (MG) by stabilizing the aqueous ferrofluid suspension ... More
Structural, electronic, and optical properties of ZrO2 from ab initio calculationsApr 13 2012Structural, electronic, and optical properties for the cubic, tetragonal, and monoclinic crystalline phases of ZrO2, as derived from it ab initio full-relativistic calculations, are presented. The electronic structure calculations were carried out by ... More
Embedding cosmological inflation, axion dark matter and seesaw mechanism in a 3-3-1 gauge modelDec 05 2016The Peccei-Quinn symmetry is an automatic symmetry of the 3-3-1 gauge models which, consequently are not plagued with the strong CP problem. Nevertheless, the axion that emerges from spontaneous breaking of Peccei-Quinn symmetry cannot be made invisible ... More
Estimation of classrooms occupancy using a multi-layer perceptronFeb 07 2017This paper presents a multi-layer perceptron model for the estimation of classrooms number of occupants from sensed indoor environmental data-relative humidity, air temperature, and carbon dioxide concentration. The modelling datasets were collected from ... More
Neutrinos and Ultra-High-Energy Cosmic-Ray Nuclei from BlazarsNov 06 2017May 18 2018We discuss the production of ultra-high-energy cosmic ray (UHECR) nuclei and neutrinos from blazars. We compute the nuclear cascade in the jet for both BL Lac objects and flat-spectrum radio quasars (FSRQs), and in the ambient radiation zones for FSRQs ... More
Invariant Measures for a Stochastic Fokker-Planck EquationMar 26 2015Jun 18 2017We study the kinetic Fokker-Planck equation perturbed by a stochastic Vlasov force term. When the noise intensity is not too large, we solve the Cauchy Problem in a class of well-localized (in velocity) functions. We also show that, when the noise intensity ... More
Probing the LDA-1/2 method as a starting point for $G_0W_0$ calculationsAug 12 2016Employing the $G_0W_0$ approximation of Hedin's $GW$ approach one can obtain quasi-particle energies of extended systems and molecules with good accuracy. However, for many materials, semi-local exchange-correlation functionals are unsatisfactory starting ... More
Multi-timescale Trajectory Prediction for Abnormal Human Activity DetectionAug 12 2019A classical approach to abnormal activity detection is to learn a representation for normal activities from the training data and then use this learned representation to detect abnormal activities while testing. Typically, the methods based on this approach ... More
On Black Hole Structures in Scalar-Tensor Theories of GravityMar 11 2016We review some properties of black hole structures appearing in gravity with a massless scalar field, with both minimal and nonminimal coupling. The main properties of the resulting cold black holes are described. The study of black holes in scalar-gravity ... More
Scalar-tensor theories with an external scalarMar 25 2015May 23 2016Scalar-tensor (ST) gravity is considered in the case where the scalar is an external field. We show that General Relativity (GR) and usual ST gravity are particular cases of the External Scalar-Tensor (EST) gravity. It is shown with a particular cosmological ... More
Harmonic factorization and reconstruction of the elasticity tensorDec 25 2016Sep 26 2017In this paper, we propose a factorization of a fourth-order harmonic tensor into second-order tensors. We obtain moreover explicit equivariant reconstruction formulas, using second-order covariants, for transverse isotropic and orthotropic harmonic fourth-order ... More
Probabilistic Argumentation. An Equational ApproachMar 18 2015There is a generic way to add any new feature to a system. It involves 1) identifying the basic units which build up the system and 2) introducing the new feature to each of these basic units. In the case where the system is argumentation and the feature ... More
Optimal Portfolio Choice for a Behavioural Investor in Continuous-Time MarketsFeb 03 2012Apr 27 2013The aim of this work consists in the study of the optimal investment strategy for a behavioural investor, whose preference towards risk is described by both a probability distortion and an S-shaped utility function. Within a continuous-time financial ... More
Red giants observed by CoRoT and APOGEE: The evolution of the Milky Way's radial metallicity gradientAug 17 2016Dec 20 2016Using combined asteroseismic and spectroscopic observations of 418 red-giant stars close to the Galactic disc plane (6 kpc $<R_{\rm Gal}\lesssim13$ kpc, $|Z_{\rm Gal}|<0.3$ kpc), we measure the age dependence of the radial metallicity distribution in ... More
Rotated Dn-latticesNov 16 2011Based on algebraic number theory we construct some families of rotated Dn-lattices with full diversity which can be good for signal transmission over both Gaussian and Rayleigh fading channels. Closed-form expressions for the minimum product distance ... More
Construction C*: an inter-level coded version of Construction CSep 19 2017Dec 27 2017Besides all the attention given to lattice constructions, it is common to find some very interesting nonlattice constellations, as Construction C, for example, which also has relevant applications in communication problems (multi-level coding, multi-stage ... More
Nonlinear interaction between electromagnetic and gravitational waves: an appraisalMay 16 2017Wave propagation of field disturbances is ubiquitous. The electromagnetic and gravitational are cousin theories in which the corresponding waves play a relevant role to understand several related physical. It has been established that small electromagnetic ... More
The Milnor Number of Plane Branches With Tame Semigroup of ValuesAug 23 2017The Milnor number of an isolated hypersurface singularity, defined as the codimension $\mu(f)$ of the ideal generated by the partial derivatives of a power series $f$ that represents locally the hypersurface, is an important topological invariant of the ... More
On the instability of some k-essence space-timesAug 24 2019We study the stability properties of static, spherically symmetric configurations in k-essence theories with the Lagrangians of the form $F(X)$, $X \equiv \phi_{,\alpha} \phi^{,\alpha}$. The instability under spherically symmetric perturbations is proved ... More
A novel determination of density, temperature and symmetry energy for nuclear multi-fragmentation through primary fragment yield reconstructionJan 02 2014Feb 17 2014For the first time primary hot isotope distributions are experimentally reconstructed in intermediate heavy ion collisions and used with antisymmetrized molecular dynamics (AMD) calculations to determine density, temperature and symmetry energy coefficient ... More