Results for "Thiago Filipe da Silva"

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Infinitesimal Lipschitz conditions on family of analytic varietiesFeb 08 2019In this work, we extend the concept of the double of an ideal defined in \cite{G2}, to the context of modules. We also obtain the genericity of the infinitesimal Lipschitz condition A for an enlarged class of analytic spaces.
Categorical Aspects of the Double Structure of a ModuleApr 27 2017Sep 28 2017In this work we develop some categorical aspects of the double structure of a module.
Graded identities of block-triangular matricesApr 16 2015Sep 13 2015Let $F$ be an infinite field and $UT(d_1,\dots, d_n)$ be the algebra of upper block-triangular matrices over $F$. In this paper we describe a basis for the $G$-graded polynomial identities of $UT(d_1,\dots, d_n)$, with an elementary grading induced by ... More
Analysis of supervised and semi-supervised GrowCut applied to segmentation of masses in mammography imagesDec 20 2017Breast cancer is already one of the most common form of cancer worldwide. Mammography image analysis is still the most effective diagnostic method to promote the early detection of breast cancer. Accurately segmenting tumors in digital mammography images ... More
Few-Photon Heteorodyne SpectroscopyJan 28 2016Mar 11 2016We perform a high resolution Fourier Transform Spectroscopy of optical sources in the few-photon regime based on the phenomenon of two-photon interference in a beam splitter. From the heterodyne interferogram between test and reference sources it is possible ... More
Linear-Optic Heralded Photon SourceJul 07 2015Nov 22 2015We present a Heralded Photon Source based only on linear optics and weak coherent states. By time-tuning a Hong-Ou-Mandel interferometer fed with frequency-displaced coherent states, the output photons can be synchronously heralded following sub-Poisson ... More
Real and complex integral closure, Lipschitz equisingularity and applications on square matricesFeb 28 2019Recently the authors investigated the Lipschitz triviality of simple germs of matrices. In this work, we improve some previous results and we present an extension of an integral closure result for the real setting. These tools are applied to investigate ... More
Robust path-following control for articulated heavy-duty vehiclesAug 07 2018Path following and lateral stability are crucial issues for autonomous vehicles. Moreover, these problems increase in complexity when handling articulated heavy-duty vehicles due to their poor manoeuvrability, large sizes and mass variation. In addition, ... More
On the Levi-Civita solutions with cosmological constantNov 03 1999The main properties of the Levi-Civita solutions with the cosmological constant are studied. In particular, it is found that some of the solutions need to be extended beyond certain hypersurfaces in order to have geodesically complete spacetimes. Some ... More
Impact of Raman scattered noise from multiple telecom channels on fiber-optic quantum key distribution systemsOct 02 2014In this paper we analyze the impact of the spontaneous Raman scattered noise generated from multiple optical classical channels on a single quantum key distribution channel, all within the telecom C-band. We experimentally measure the noise generated ... More
Role of dimensionality in preferential attachment growth in the Bianconi-Barabási modelApr 28 2017Jul 28 2017Scale-free networks are quite popular nowadays since many systems are well represented by such structures. In order to study these systems, several models were proposed. However, most of them do not take into account the node-to-node Euclidean distance, ... More
A semi-supervised fuzzy GrowCut algorithm to segment and classify regions of interest of mammographic imagesDec 03 2017According to the World Health Organization, breast cancer is the most common form of cancer in women. It is the second leading cause of death among women round the world, becoming the most fatal form of cancer. Mammographic image segmentation is a fundamental ... More
The Bi-Lipschitz Equisingularity of Essentially Isolated Determinantal SingularitiesMay 10 2017Oct 18 2017The bi-Lipschitz geometry is one of the main subjects in the modern approach of Singularity Theory. However, it rises from works of important mathematicians of the last century, especially Zariski. In this work we investigate the Bi-Lipschitz equisingularity ... More
Scaling properties of d-dimensional complex networksOct 03 2018Jan 03 2019The area of networks is very interdisciplinary and exhibits many applications in several fields of science. Nevertheless, there are few studies focusing on geographically located $d$-dimensional networks. In this paper, we study scaling properties of ... More
Inference on Dynamic Models for non-Gaussian Random Fields using INLA: A Homicide Rate Analysis of Brazilian CitiesDec 24 2013Feb 13 2015Robust time series analysis is an important subject in statistical modeling. Models based on Gaussian distribution are sensitive to outliers, which may imply in a significant degradation in estimation performance as well as in prediction accuracy. State-space ... More
High Level Pattern Classification via Tourist Walks in NetworksMay 07 2013Complex networks refer to large-scale graphs with nontrivial connection patterns. The salient and interesting features that the complex network study offer in comparison to graph theory are the emphasis on the dynamical properties of the networks and ... More
Safeguarding Quantum Key Distribution through Detection RandomizationOct 02 2014We propose and experimentally demonstrate a scheme to render the detection apparatus of a Quantum Key Distribution system immune to the main classes of hacking attacks in which the eavesdropper explores the back-door opened by the single-photon detectors. ... More
Dynamical matrix for arbitrary quadratic fermionic bath Hamiltonians and non-Markovian dynamics of one and two qubits in an Ising model environmentJul 08 2015Apr 11 2017We obtain the analytical expression for the Kraus decomposition of the quantum map of an environment modeled by an arbitrary quadratic fermionic Hamiltonian acting on one or two qubits, and derive simple functions to check the non-positivity of the intermediate ... More
Spectral characterization of weak coherent state sources based on two-photon interferenceJul 08 2015We demonstrate a method for characterizing the coherence function of coherent states based on two-photon interference. Two states from frequency mismatched faint laser sources are fed into a Hong-Ou-Mandel interferometer and the interference pattern is ... More
Evolution through time of Pyrrolizidine Alkaloids detection and quantificationDec 23 2013Pyrrolizidine Alkaloids (PAs) are a group of naturally occurring alkaloids that are produced by plants as a defense mechanism against insect herbivores. The analytical methodologies employed for their detection have come a long way since the first analytical ... More
Network-based stochastic competitive learning approach to disambiguation in collaborative networksMar 02 2013Many patterns have been uncovered in complex systems through the application of concepts and methodologies of complex networks. Unfortunately, the validity and accuracy of the unveiled patterns are strongly dependent on the amount of unavoidable noise ... More
Discriminating word senses with tourist walks in complex networksJun 17 2013Patterns of topological arrangement are widely used for both animal and human brains in the learning process. Nevertheless, automatic learning techniques frequently overlook these patterns. In this paper, we apply a learning technique based on the structural ... More
Word sense disambiguation via high order of learning in complex networksFeb 18 2013Complex networks have been employed to model many real systems and as a modeling tool in a myriad of applications. In this paper, we use the framework of complex networks to the problem of supervised classification in the word disambiguation task, which ... More
Inflationary Super-Hubble Waves and the Size of the UniverseApr 03 2013Sep 22 2013The effect of the scalar spectral index on inflationary super-Hubble waves is to amplify/damp large wavelengths according to whether the spectrum is red ($n_{s}<1$) or blue ($n_{s}>1$). As a consequence, the large-scale temperature correlation function ... More
On The Cauchy Problem for the elliptic Zakharov-Schulman system in dimensions 2 and 3Feb 03 2010Jun 23 2011We prove that the Cauchy problem associated to the Zakharov-Schulman system $iu_t+L_1u=uv$, $L_2v=L_3(|u|^2)$ is locally well-posed for given initial data in Sobolev spaces $H^s(R^n)$, $s\geq n/4$, for n =2,3. Here, L_j denote second order operators, ... More
On Equilibrium Prices in Continuous TimeFeb 25 2008We combine general equilibrium theory and theorie generale of stochastic processes to derive structural results about equilibrium state prices.
A solid-state entangled photon pair source with high brightness and indistinguishabilityMar 04 2019The generation of high-quality entangled photon pairs has been being a long-sought goal in modern quantum communication and computation. To date, the most widely-used entangled photon pairs are generated from spontaneous parametric downconversion, a process ... More
On a nonlinear Schrödinger system arising in quadratic mediaMar 30 2017Jul 20 2017We consider the quadratic Schr\"odinger system $$iu_t+\Delta_{\gamma_1}u+\overline{u}v=0$$ $$2iv_t+\Delta_{\gamma_2}v-\beta v+\frac 12 u^2=0,$$ where $t\in\mathbf{R},\,x\in \mathbf{R}^d\times \mathbf{R}$, in dimensions $1\leq d\leq 4$ and for $\gamma_1,\gamma_2>0$, ... More
Electromagnetically Induced Transparency of On-demand Single Photons in a Hybrid Quantum NetworkAug 17 2018Long range quantum communication and quantum information processing require the development of light-matter interfaces for distributed quantum networks. Even though photons are ideal candidates for network links to transfer quantum information, the system ... More
Isoperimetric regions in H^2 between parallel horocyclesJun 22 2009Oct 21 2009In this work we investigate the following isoperimetric problem in the hyperbolic plane: to find the regions of prescribed area with minimal perimeter between two parallel horocycles. We give an explicit and detailed description of all such regions.
Noncommutative Lp-Spaces and Perturbations of KMS StatesJun 09 2018Aug 09 2018We extend the theory of perturbations of KMS states to some class of unbounded perturbations using noncommutative Lp-spaces. We also prove certain stability of the domain of the Modular Operator associated to a ||.||p-continuous state. This allows us ... More
On the Gorensteinization of Schubert Varieties via Boundary DivisorsJul 14 2018We will describe a one-step "Gorensteinization" process for a Schubert variety by blowing-up along its boundary divisor. The local question involves Kazhdan-Lusztig varieties which can be degenerated to affine toric schemes defined using the Stanley-Reisner ... More
Strong laws of large numbers for arrays of row-wise extended negatively dependent random variablesApr 02 2019The main purpose of this paper is to obtain strong laws of large numbers for arrays or weighted sums of random variables under a scenario of dependence. Namely, for triangular arrays $\{X_{n,k}, \, 1 \leqslant k \leqslant n, \, n \geqslant 1 \}$ of row-wise ... More
Spatial patterns of random walkers under evolution of the attractiveness: persistent nodes, degree distribution, and spectral propertiesOct 01 2017In this paper we explore the features of a graph generated by random walkers with nodes that have evolutionary attractiveness and Boltzmann-like transition probabilities that depend both on the euclidean distance between the nodes and on the ratio ($\beta ... More
A Model-Predictive Motion Planner for the IARA Autonomous CarNov 14 2016Nov 09 2017We present the Model-Predictive Motion Planner (MPMP) of the Intelligent Autonomous Robotic Automobile (IARA). IARA is a fully autonomous car that uses a path planner to compute a path from its current position to the desired destination. Using this path, ... More
Nested distance for stagewise-independent processesNov 29 2017We prove that, for two discrete-time stagewise-independent processes with a stagewise metric, the nested distance is equal to the sum of the Wasserstein distances between the marginal distributions of each stage.
Resonance fluorescence of GaAs quantum dots with near-unity photon indistinguishabilityJan 28 2019Photonic quantum technologies call for scalable quantum light sources that can be integrated, while providing the end user with single and entangled photons on-demand. One promising candidate are strain free GaAs/AlGaAs quantum dots obtained by droplet ... More
Map Memorization and Forgetting in the IARA Autonomous CarOct 04 2018In this work, we present a novel strategy for correcting imperfections in occupancy grid maps called map decay. The objective of map decay is to correct invalid occupancy probabilities of map cells that are unobservable by sensors. The strategy was inspired ... More
Lecture Notes on Noncommutative Lp-SpacesMar 06 2018These lecture notes were written during a mini-course on noncommutative Lp-spaces at the Basque Center of Applied Mathematics. It starts presenting the theory of weights and traces in von Neumann algebra, followed by the theory of noncommutative measure. ... More
Ressonant elliptic problems under Cerami conditionMay 11 2012We establish existence and multiplicity of solutions for a elliptic resonant elliptic problem under Dirichlet boundary conditions.
New Identities from a Combinatorial Approach to Generalized Fibonacci and Generalized Lucas NumbersDec 12 2013Sep 04 2016We present here some new identities for generalizations of Fibonacci and Lucas numbers by combinatorially interpreting these numbers in terms of numbers of certain tilings of a $1 \times m$ board. As a consequence, some new interesting identities involving ... More
Almost sure convergence for weighted sums of pairwise PQD random variablesDec 24 2018We obtain Marcinkiewicz-Zygmund strong laws of large numbers for weighted sums of pairwise positively quadrant dependent random variables stochastically dominated by a random variable $X \in \mathscr{L}_{p}$, $1 \leqslant p < 2$. We use our results to ... More
Perturbations of KMS States and Noncommutative Lp-spacesNov 12 2018Mar 20 2019We extend the theory of perturbations of KMS states to a class of unbounded perturbations using noncommutative $L_p$-spaces. We also prove certain stability of the domain of the Modular Operator associated with a ||.||p-continuous state. This allows us ... More
Properties of G-Equivalence of MatricesNov 02 2017The theorem of Hilbert- Burch provides a description of codimension two determinantal varieties and their deformations in terms of their presentation matrices. In this work we use this correspondence to study properties of determinantal varieties, based ... More
Fold-Forms for Four-FoldsSep 22 2009This paper explains an application of Gromov's h-principle to prove the existence, on any orientable 4-manifold, of a folded symplectic form. That is a closed 2-form which is symplectic except on a separating hypersurface where the form singularities ... More
An Alternative Approach for General Covariant Horava-Lifshitz Gravity and Matter CouplingSep 24 2010Feb 14 2011Recently, Horava and Melby-Thompson proposed in arXiv:1007.2410 a nonrelativistic gravity theory with extended gauge symmetry that is free of the spin-0 graviton. We propose a minimal substitution recipe to implement this extended gauge symmetry which ... More
On the convergence of series of moments for row-wise sums of random variablesJan 18 2019Given a triangular array $\left\{X_{n,k}, \, 1 \leqslant k \leqslant n, n \geqslant 1 \right\}$ of random variables satisfying $\mathbb{E} \lvert X_{n,k} \rvert^{p} < \infty$ for some $p \geqslant 1$ and sequences $\{b_{n} \}$, $\{c_{n} \}$ of positive ... More
Continuity of generalized wave maps on the sphereApr 09 2012Jul 25 2012We consider a generalization of wave maps based on the Adkins-Nappi model of nuclear physics. In particular, we show that solutions to this equation remain continuous at the origin, which is a first step towards establishing a regularity theory for this ... More
Asymptotic behavior for a non-autonomous model of neural fields with variable external stimulusDec 28 2017Mar 14 2018In this work we consider a class of nonlocal non-autonomous evolution equations, which generalizes the model of neuronal activity that arises in Amari (1979). Under suitable assumptions on the nonlinearity and on the parameters present in the equation, ... More
Quarkonia measurement in p+p and d+Au collisions at sqrt(s)=200 GeV by PHENIX DetectorJul 27 2009Sep 27 2009We report new quarkonia measurements necessary to understand production mechanisms and cold nuclear matter effects in the yields observed at RHIC energy. Results obtained in p+p collisions collected during the 2006 RHIC Run include J/psi, Psi' and Upsilon ... More
Strict Bott-Samelson Resolutions of Schubert VarietiesFeb 11 2017Jan 02 2018We explore the relationship between two desingularization techniques for Schubert varieties. The Bott-Samelson resolution is the more common of the two, but it fails to encompass many properties that Hironaka resolutions provide, in particular, being ... More
On the spectral properties of real anti-tridiagonal Hankel matricesFeb 19 2019In this paper we express the eigenvalues of real anti-tridiagonal Hankel matrices as the zeros of given rational functions. We still derive eigenvectors for these structured matrices at the expense of prescribed eigenvalues.
A method to identify and characterise binary candidates - a study of CoRoT dataMar 25 2011Mar 31 2011The analysis of the CoRoT space mission data was performed aiming to test a method that selects, among the several light curves observed, the transiting systems that likely host a low-mass star orbiting the main target. The method identifies stellar companions ... More
Multilevel LDPC Lattices with Efficient Encoding and Decoding and a Generalization of Construction D'Dec 21 2017Nov 22 2018Lattice codes are elegant and powerful structures that not only can achieve the capacity of the AWGN channel but are also a key ingredient to many multiterminal schemes that exploit linearity properties. However, constructing lattice codes that can realize ... More
Primeness property for central polynomials of verbally prime P.I. algebrasJul 04 2014Jul 07 2014Let $f$ and $g$ be two noncommutative polynomials in disjoint sets of variables. An algebra $A$ is verbally prime if whenever $f\cdot g$ is an identity for $A$ then either $f$ or $g$ is also an identity. As an analogue of this property Regev proved that ... More
Lyapunov exponents and partial hyperbolicity of chain control sets on flag manifoldsMar 14 2018Nov 03 2018For a right-invariant control system on a flag manifold $\mathbb{F}_{\Theta}$ of a real semisimple Lie group, we relate the $\mathfrak{a}$-Lyapunov exponents to the Lyapunov exponents of the system over regular points. Moreover, we adapt the concept of ... More
On the characterization of the controllability property for linear control systems on nonnilpotent, solvable three-dimensional Lie groupsApr 25 2018Dec 12 2018In this paper we show that a complete characterization of the controllability property for linear control system on three-dimensional solvable nonnilpotent Lie groups is possible by the LARC and the knowledge of the eigenvalues of the derivation associated ... More
Characterization of Spherical and Plane Curves Using Rotation Minimizing FramesJun 06 2017Jun 24 2017In this work we furnish characterizations of spherical and plane curves using rotation minimizing frames. Due to their minimal twist, in many contexts these frames are preferable over the usual Frenet one, such as in motion design, sweep surface modeling, ... More
The geometry of Gauss map and shape operator in simply isotropic and pseudo-isotropic spacesJan 03 2018Mar 19 2019In this work we are interested in the differential geometry of surfaces in simply isotropic $\mathbb{I}^3$ and pseudo-isotropic $\mathbb{I}_{\mathrm{p}}^3$ spaces, which consists in the study of $\mathbb{R}^3$ equipped with a degenerate metric such as ... More
Ferromagnetism in Dilute Magnetic SemiconductorsNov 16 2010We study the ferromagnetism of Ga1-xMnxAs by using a model Hamiltonian, based on an impurity band and the anti-ferromagnetic exchange interaction between the spins of Mn atoms and the charge carriers in the impurity band. Based on the mean field approach ... More
Differential geometry of spherical curves and manifolds with constant sectional curvatureSep 16 2018Oct 30 2018It is known that the so-called rotation minimizing (RM) frames allow for a simple and elegant characterization of geodesic spherical curves in Euclidean, hyperbolic, and spherical spaces through a certain linear equation involving the coefficients that ... More
Exact Effective Action for (1+1 Dimensional) Fermions in an Abelian Background at Finite TemperatureAug 05 1998Aug 10 1998In an effort to further understand the structure of effective actions for fermions in an external gauge background at finite temperature, we study the example of 1+1 dimensional fermions interacting with an arbitrary Abelian gauge field. We evaluate the ... More
Continuity of reachable sets of restricted affine control systemsJun 20 2016In this paper we give a direct proof that for a restricted affine control system on a connected manilfold M, the associated reachable sets up to time t varies continuously with the Haudorff metric.
Analyzing Peer Selection Policies for BitTorrent Multimedia On-Demand Streaming Systems in InternetFeb 10 2014The adaptation of the BitTorrent protocol to multimedia on-demand streaming systems essentially lies on the modification of its two core algorithms, namely the piece and the peer selection policies, respectively. Much more attention has though been given ... More
Photospheric parameters and C abundances in solar-like stars with and without planetsOct 01 2009We have been analyzing a large sample of solar-like stars with and without planets in order to homogeneously measure their photospheric parameters and Carbon abundances. Our sample contains around 200 stars in the solar neighborhood observed with the ... More
Hyperbolic Chain Control Sets on Flag ManifoldsFeb 24 2014In this paper we study the chain control sets of right-invariant control systems on the flag manifolds of a non-compact semisimple Lie group. We prove that each chain control set is partially (skew-) hyperbolic over the associated control flow. Moreover, ... More
Rigidity for critical metrics of the volume functionalJun 22 2017Sep 25 2017Geodesic balls in a simply connected space forms $\mathbb{S}^n$, $\mathbb{R}^{n}$ or $\mathbb{H}^{n}$ are distinguished manifolds for comparison in bounded Riemannian geometry. In this paper we show that they have the maximum possible boundary volume ... More
Invariance entropy for a class of partially hyperbolic setsNov 03 2017May 09 2018Invariance entropy is a measure for the smallest data rate in a noiseless digital channel above which a controller that only receives state information through this channel is able to render a given subset of the state space invariant. In this paper, ... More
Harmonically free group actions and equivariant bifurcation in the Yamabe problemNov 18 2016We study multiplicity of constant scalar curvature metrics in products of a compact closed manifold and a compact manifold with boundary using equivariant bifurcation theory.
Segmented Tau Approximation for a Non-Autonomous Functional Differential Equation of Mixed TypeAug 01 2016Aug 04 2016The segmented formulation of the Tau method is used to numerically solve the non-autonomous forward-backward functional differential equation x'(t) = a(t)x(t) + b(t)x(t-1) + c(t)x(t+1), where x is the unknown function, a, b, and c are known functions. ... More
The control set of a linear control system on the two dimensional solvable Lie groupNov 09 2018In this paper we explicitly calculate the control sets associated with a linear control system on the two dimensional solvable Lie group. We show that a linear control system of such kind admits exactly one control set or infinite control sets depending ... More
On the Optimization of BitTorrent-Like Protocols for Interactive On-Demand Streaming SystemsOct 08 2014This paper proposes two novel optimized BitTorrent-like protocols for interactive multimedia streaming: the Simple Interactive Streaming Protocol (SISP) and the Exclusive Interactive Streaming Protocol (EISP). The former chiefly seeks a trade-off between ... More
Robustness of critical bit rates for practical stabilization of networked control systemsOct 24 2016In this paper we address the question of robustness of critical bit rates for the stabilization of networked control systems over digital communication channels. For a deterministic nonlinear system, the smallest bit rate above which practical stabilization ... More
Moving frames and the characterization of curves that lie on a surfaceJul 19 2016Jul 17 2017In this work we are interested in the characterization of curves that belong to a given surface. To the best of our knowledge, there is no known general solution to this problem. Indeed, a solution is only available for a few examples: planes, spheres, ... More
Invariance Entropy of Hyperbolic Control SetsAug 11 2014In this paper, we improve the known estimates for the invariance entropy of a nonlinear control system. For sets of complete approximate controllability we derive an upper bound in terms of Lyapunov exponents and for uniformly hyperbolic sets we obtain ... More
Differential geometry of invariant surfaces in simply isotropic and pseudo-isotropic spacesSep 28 2018Nov 14 2018We study invariant surfaces generated by one-parameter subgroups of simply and pseudo isotropic rigid motions. Basically, simply and pseudo isotropic geometries are the study of a three-dimensional space equipped with a rank 2 metric of index zero and ... More
On Oda's Strong Factorization ConjectureNov 24 2009The Oda's Strong Factorization Conjecture states that a proper birational map between smooth toric varieties can be decomposed as a sequence of smooth toric blowups followed by a sequence of smooth toric blowdowns. This article describes an algorithm ... More
Characterization of curves that lie on a geodesic sphere or on a totally geodesic hypersurface in a hyperbolic space or in a sphereJul 23 2017Mar 26 2018The consideration of the so-called rotation minimizing frames allows for a simple and elegant characterization of plane and spherical curves in Euclidean space via a linear equation relating the coefficients that dictate the frame motion. In this work, ... More
Galois Groups in the work of Mira FernandesJan 08 2011In connection to a review of the writings on Galois Theory of the Portuguese mathematician Aureliano Mira Fernandes at turn of the XXth century a brief narrative is presented on how the group theory concepts discovered by Galois are connected to previous ... More
Classification of holomorphic foliations of arbitrary codimension on Hopf manifoldsNov 11 2015We classify nonsingular holomorphic distributions of arbitrary codimension on certain Hopf manifolds. We prove that all holomorphic distribution of codimension k on a generic Hopf manifold is induced by a mononial holomorphic k-form.
On Static Manifolds and Related Critical Spaces with cyclic parallel Ricci tensorNov 11 2018The aim of this paper is to classify three dimensional compact Riemannian manifolds $(M^{3},g)$ that admits a non-constant solution to the equation $$-\Delta f g+Hess f-fRic=\mu Ric+\lambda g,$$ for some special constants $(\mu, \lambda)$, under assumption ... More
Las Vergnas Cube Conjecture and reconstruction properties of the cube matroidAug 05 2005Las Vergnas Cube Conjecture states that the cube matroid has exactly one class of orientations. We prove that this conjecture is equivalent to saying that the oriented matroid of the affine dependencies of the n-cube can be reconstructed from the underlying ... More
Rotation minimizing frames and spherical curves in simply isotropic and pseudo-isotropic 3-spacesJul 19 2017Sep 03 2018In this work, we are interested in the differential geometry of curves in the simply isotropic and pseudo-isotropic 3-spaces, which are examples of Cayley-Klein geometries whose absolute figure is given by a plane at infinity and a degenerate quadric. ... More
Surfaces of revolution with prescribed mean and skew curvatures in Lorentz-Minkowski spaceApr 01 2018Apr 11 2018In this work, we investigate the problem of finding surfaces in the Lorentz-Minkowski 3-space with prescribed skew (S) and mean (H) curvatures, which are defined through the discriminant of the characteristic polynomial of the shape operator and its trace, ... More
Self-Driving Cars: A SurveyJan 14 2019We survey research on self-driving cars published in the literature focusing on autonomous cars developed since the DARPA challenges, which are equipped with an autonomy system that can be categorized as SAE level 3 or higher. The architecture of the ... 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
Comment on "Quasinormal modes of Schwarzschild anti de Sitter black holes: Electromagnetic and gravitational perturbations"Oct 14 2015The quasinormal modes of the electromagnetic and gravitational perturbation on Schwarzschild-AdS black hole calculated by Cardoso and Lemos has been revisited. Although the equations of motion are correct some frequencies calculated previously by the ... More
You are What you Eat (and Drink): Identifying Cultural Boundaries by Analyzing Food & Drink Habits in FoursquareApr 03 2014Food and drink are two of the most basic needs of human beings. However, as society evolved, food and drink became also a strong cultural aspect, being able to describe strong differences among people. Traditional methods used to analyze cross-cultural ... More
Copycat CNN: Stealing Knowledge by Persuading Confession with Random Non-Labeled DataJun 14 2018In the past few years, Convolutional Neural Networks (CNNs) have been achieving state-of-the-art performance on a variety of problems. Many companies employ resources and money to generate these models and provide them as an API, therefore it is in their ... More
Gender Matters! Analyzing Global Cultural Gender Preferences for Venues Using Social SensingMar 18 2017Gender differences is a phenomenon around the world actively researched by social scientists. Traditionally, the data used to support such studies is manually obtained, often through surveys with volunteers. However, due to their inherent high costs because ... More
A Fully Attention-Based Information RetrieverOct 22 2018Recurrent neural networks are now the state-of-the-art in natural language processing because they can build rich contextual representations and process texts of arbitrary length. However, recent developments on attention mechanisms have equipped feedforward ... More
Regularized Fuzzy Neural Networks to Aid Effort Forecasting in the Construction and Software DevelopmentDec 04 2018Predicting the time to build software is a very complex task for software engineering managers. There are complex factors that can directly interfere with the productivity of the development team. Factors directly related to the complexity of the system ... More
Fuzzy neural networks to create an expert system for detecting attacks by SQL InjectionJan 09 2019Its constant technological evolution characterizes the contemporary world, and every day the processes, once manual, become computerized. Data are stored in the cyberspace, and as a consequence, one must increase the concern with the security of this ... More
Perturbation of a nonautonomous problem in $\mathbb{R}^n$Nov 22 2011In this paper we prove a stability result about the asymptotic dynamics of a perturbed nonautonomous evolution equation in $\mathbb{R}^n$ governed by a maximal monotone operator.
Extended $Λ$CDM modelSep 20 2018Oct 01 2018In this work we discuss a general approach for the dissipative dark matter considering a nonextensive bulk viscosity and taking into account the role of generalized Friedmann equations. This generalized $\Lambda$CDM model encompasses a flat universe with ... More
A constrained shape optimization problem in Orlicz-Sobolev spacesMay 18 2018In this manuscript we study the following optimization problem: given a bounded and regular domain $\Omega\subset \mathbb{R}^N$ we look for an optimal shape for the "$\mathrm{W}-$vanishing window" on the boundary with prescribed measure over all admissible ... More
SafeGuardPF: Safety Guaranteed Reactive Potential Fields for Mobile Robots in Unknown and Dynamic EnvironmentsSep 22 2016An autonomous navigation with proven collision avoidance in unknown and dynamic environments is still a challenge, particularly when there are moving obstacles. A popular approach to collision avoidance in the face of moving obstacles is based on model ... More
Graded identities of simple real graded division algebrasOct 09 2015Feb 26 2016Let A and B be finite dimensional simple real algebras with division gradings by an abelian group G. In this paper we give necessary and sufficient conditions for the coincidence of the graded identities of A and B. We also prove that every finite dimensional ... More
A general system of differential equations to model first order adaptive algorithmsOct 31 2018First order optimization algorithms play a major role in large scale machine learning. A new class of methods, called adaptive algorithms, were recently introduced to adjust iteratively the learning rate for each coordinate. Despite great practical success ... More
The strong coupling regime of twelve flavors QCDNov 15 2012We summarize the results recently reported in Ref.[1] [A. Deuzeman, M.P. Lombardo, T. Nunes da Silva and E. Pallante,"The bulk transition of QCD with twelve flavors and the role of improvement"] for the SU(3) gauge theory with Nf=12 fundamental flavors, ... More