Results for "Pedro F. Ramírez"

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Rotating black holes in the FI-gauged $N=2$, $D=4$ $\overline{\mathbb{C}\text{P}}^n$ modelFeb 08 2019We construct supersymmetric black holes with rotation or NUT charge for the $\overline{\mathbb{C}\text{P}}^n$- and the $\text{t}^3$ model of $N=2$, $D=4$ $\text{U}(1)$ FI-gauged supergravity. The solutions preserve 2 real supercharges, which are doubled ... More
Populating Low-Spin States in Radioactive Nuclei to Measure Magnetic Moments Using the Transient Field TechniqueJan 13 2016The experimental study of magnetic moments for nuclear states near the ground state, $I \ge 2$, provides a powerful tool to test nuclear structure models. The study of magnetic moments in nuclei far away from the stability line is the next frontier in ... More
Asymptotic direction for random walks in mixing random environmentsOct 16 2016We prove that every random walk in a uniformly elliptic random environment satisfying the cone mixing condition and a non-effective polynomial ballisticity condition with high enough degree has an asymptotic direction.
New examples of ballistic RWRE in the low disorder regimeAug 04 2018We give a new criterion for ballistic behavior of random walks in random environments which are low disorder perturbations of the simple symmetric random walk on $\mathbb{Z}^d$, for $d\geq 2$. This extends the results established by Sznitman in 2003 and, ... More
Asymptotic directions in random walks in random environment revisitedFeb 06 2009Recently Simenhaus proved that for any elliptic random walk in random environment, transience in the neighborhood of a given direction is equivalent to the a.s. existence of a deterministic asymptotic direction and to transience in any direction in the ... More
A proof of Sznitman's conjecture about ballistic RWRESep 06 2018Oct 08 2018We consider a random walk in a uniformly elliptic i.i.d. random environment in $\mathbb Z^d$ for $d\ge 2$. It is believed that whenever the random walk is transient in a given direction it is necessarily ballistic. In order to quantify the gap which would ... More
On extreme faces of projective point configurationsOct 05 2018In this paper we investigate a problem concerning configurations of points obtained through permissible projective transformations. We investigate the maximum number of vertices and facets of the polytope formed by taking the convex hull of such configurations. ... More
On Ramsey numbers of complete graphs with dropped starsOct 14 2013Mar 31 2016Let $r(G,H)$ be the smallest integer $N$ such that for any $2$-coloring (say, red and blue) of the edges of $K\_n$, $n\geqslant N$, there is either a red copy of $G$ or a blue copy of $H$. Let $K\_n-K\_{1,s}$ be the complete graph on $n$ vertices from ... More
Adaptive Market Efficiency of Agricultural Commodity Futures ContractsDec 27 2014Mar 31 2015In this paper we investigate the adaptive market efficiency of the agricultural commodity futures market, using a sample of eight futures contracts. Using a battery of nonlinear tests, we uncover the nonlinear serial dependence in the returns series. ... More
Quench dynamics and defects formation in the Ising chain in a transverse magnetic fieldDec 31 2018We study analytically and numerically quench dynamics and defects formation in the quantum Ising model in the presence of a time-dependent transverse magnetic field. We generalize the Landau-Ziner formula to the case of non-adiabatic evolution of the ... More
Sharp ellipticity conditions for ballistic behavior of random walks in random environmentOct 23 2013Feb 05 2016We sharpen ellipticity criteria for random walks in i.i.d. random environments introduced by Campos and Ram\'{\i}rez which ensure ballistic behavior. Furthermore, we construct new examples of random environments for which the walk satisfies the polynomial ... More
Codimension two and three Kneser TransversalsJan 04 2016Sep 27 2016Let $k,d,\lambda \geqslant 1$ be integers with $d\geqslant \lambda $ and let $X\subset\mathbb{R}^{d}$ be a finite set. A $(d-\lambda)$-plane $L$ transversal to the convex hull of all $k$-sets of $X$ is called Kneser transversal. If in addition $L$ contains ... More
Möbius function of semigroup posets through Hilbert seriesApr 23 2014Mar 31 2016In this paper, we investigate the M{\"o}bius function $\mu\_{\mathcal{S}}$ associated to a (locally finite) poset arising from a semigroup $\mathcal{S}$ of $\mathbb{Z}^m$. We introduce and develop a new approach to study $\mu\_{\mathcal{S}}$ by using ... More
On tachyon and sub-quantum phantom cosmologiesAug 30 2004This paper deals with dark and phantom energy in the tachyon and sub-quantum models for dark energy. We obtain that the simplest condition for such a regime to occur in these scenarios is that the scalar field be Wick rotated to imaginary values which ... More
Dark energy without dark energyAug 29 2006It is proposed that the current acceleration of the universe is not originated by the existence of a mysterious dark energy fluid nor by the action of extra terms in the gravity Lagrangian, but just from the sub-quantum potential associated with the CMB ... More
Some notes on the Big TripJul 20 2006The big trip is a cosmological process thought to occur in the future by which the entire universe would be engulfed inside a gigantic wormhole and might travel through it along space and time. In this paper we discuss different arguments that have been ... More
Tensorial perturbations in the bulk of inflating brane worldsAug 21 2003In this paper we consider the stability of some inflating brane-world models in quantum cosmology. It is shown that whereas the singular model based on the construction of inflating branes from Euclidean five-dimensional anti-de Sitter space is unstable ... More
Non-Abelian bubbles in microstate geometriesAug 03 2016Sep 05 2016We find the first smooth microstate geometries with non-Abelian fields. The solutions constitute an extension of the BPS three-charge smooth microstates. These consist in general families of regular supersymmetric solutions with non-trivial topology, ... More
Transition from the annealed to the quenched asymptotics for a random walk on random obstaclesJan 07 2005Feb 28 2006In this work we study a natural transition mechanism describing the passage from a quenched (almost sure) regime to an annealed (in average) one, for a symmetric simple random walk on random obstacles on sites having an identical and independent law. ... More
A $(p,q)$-Analogue of Poly-Euler Polynomials and Some Related PolynomialsApr 13 2016In the present article, we introduce a $(p,q)$-analogue of the poly-Euler polynomials and numbers by using the $(p,q)$-polylogarithm function. These new sequences are generalizations of the poly-Euler numbers and polynomials. We give several combinatorial ... More
Stable limit laws and structure of the scaling function for reaction-diffusion in random environmentJun 20 2017We prove the emergence of stable fluctuations for reaction-diffusion in random environment with Weibull tails. This completes our work around the quenched to annealed transition phenomenon in this context of reaction diffusion. In [9], we had already ... More
Dipolariton formation in quantum dot molecules strongly coupled to optical resonatorsSep 18 2016In this theoretical work, we study a double quantum dot interacting strongly with a microcavity, while undergoing resonant tunneling. Effects of interdot tunneling on the light-matter hybridized states are determined, and tunability of their brightness ... More
Velocity estimates for symmetric random walks at low ballistic disorderJan 23 2017We derive asymptotic estimates for the velocity of random walks in random environments which are perturbations of the simple symmetric random walk but have a small local drift in a given direction. Our estimates complement previous results presented by ... More
Equilibration of Concentrated Hard Sphere FluidsNov 17 2010Mar 31 2011We report a systematic molecular dynamics study of the isochoric equilibration of hard-sphere fluids in their metastable regime close to the glass transition. The thermalization process starts with the system prepared in a non-equilibrium state with the ... More
Scene Grammars, Factor Graphs, and Belief PropagationJun 03 2016We consider a class of probabilistic grammars for generating scenes with multiple objects. Probabilistic scene grammars capture relationships between objects using compositional rules that provide important contextual cues for inference with ambiguous ... More
One Thousand and One BubblesSep 12 2017Oct 03 2017We propose a novel strategy that permits the construction of completely general five-dimensional microstate geometries on a Gibbons-Hawking space. Our scheme is based on two steps. First, we rewrite the bubble equations as a system of linear equations ... More
First-principles Predictor of the Location of Ergodic-Non-ergodic TransitionsDec 13 2007This letter presents a remarkably simple approach to the first-principles determination of the ergodic-non-ergodic transition in monodisperse colloidal suspensions. It consists of an equation for the long-time asymptotic value $\gamma$ of the mean squared ... More
Phantom thermodynamicsJul 20 2004This paper deals with the thermodynamic properties of a phantom field in a flat Friedmann-Robertson-Walker universe. General expressions for the temperature and entropy of a general dark-energy field with equation of state $p=\omega\rho$ are derived from ... More
Stable equivariant abelianization, its properties, and applicationsApr 01 2008Oct 13 2016Let $G$ be a finite group. For a based $G$-space $X$ and a Mackey functor $M$, a topological Mackey functor $X\widetilde\otimes M$ is constructed, which will be called the stable equivariant abelianization of $X$ with coefficients in $M$. When $X$ is ... More
Bigraded Equivariant Cohomology of Real QuadricsMay 28 2006We give a complete description of the bigraded Bredon cohomology ring of smooth projective real quadrics, with coefficients in the constant Mackey functor $ \mathbf{Z} $. These invariants are closely related to the integral motivic cohomology ring, which ... More
Thermal radiation from Lorentzian traversable wormholesJul 23 2009In this paper we show that, analogously to as it occurs for black holes, there exist three well-defined laws for Lorentzian wormhole thermodynamics and that these laws are related with a thermal phantom-like radiation process coming from the wormhole ... More
Wormholes in the accelerating universeApr 13 2007We discuss different arguments that have been raised against the viability of the big trip process, reaching the conclusions that this process can actually occur by accretion of phantom energy onto the wormholes and that it is stable and might occur in ... More
Accelerating Hilbert-Einstein universe without dynamic dark energySep 10 2006By using an unmodified Einstein gravity theory it is shown that all of the speeding-up effects taking place in the current universe are entirely due to the quantum effects associated with the background radiation or to the combination of such effects ... More
Integral Deligne Cohomology for Real VarietiesOct 13 2008We develop an integral version of Deligne cohomology for smooth proper real varieties. For this purpose the role played by singular cohomology in the complex case has to be replaced by ordinary bigraded G-equivariant cohomology, where G=Gal(C/R). This ... More
How Anisotropic is our Universe?May 20 1996Large-scale cosmic microwave background anisotropies in homogeneous, globally anisotropic cosmologies are investigated. We perform a statistical analysis in which the four-year data from the Cosmic Background Explorer satellite is searched for the specific ... More
Quantum Spherical Spins with Local SymmetryOct 30 2014Feb 12 2015We construct a quantum system of spherical spins with a continuous local symmetry. The model is exactly soluble in the thermodynamic limit and exhibits a number of interesting properties. We show that the local symmetry is spontaneously broken at finite ... More
Four-derivative interactions in asymptotically safe gravitySep 17 2009We summarize recent progress in understanding the role of higher-derivative terms in the asymptotic safety scenario of gravity. Extending previous computations based on the functional renormalization group approach by including a Weyl-squared term in ... More
Implications of $D^0-\overline{D^0}$ on the rare top quark decays $t\to uγ$ and $t\to ug$Jun 03 2009The recently observed mass difference of the $D^0-\overline{D^0}$ mixing is used to predict the branching ratios of the rare top quark decays $t\to u\gamma$ and $t\to ug$ in a model independent way using the effective Lagrangian approach. It is found ... More
The $Z_H \to γH$ decay in the Littlest Higgs ModelJan 20 2015Sep 27 2015We present the calculation of the $Z_H \to \gamma H$ decay in the context of the Littlest Higgs model at one-loop level. Our calculations include the contributions of fermions, scalars and gauge bosons in accordance with the most recent experimental constraints ... More
Higgs mediated lepton flavor violating tau decays $τ\to μγ$ and $τ\to μγγ$ in effective theoriesApr 16 2008The size of the branching ratios for the $\tau \to \mu \gamma$ and $\tau \to \mu \gamma \gamma$ decays induced by a lepton flavor violating Higgs interaction $H\tau \mu$ is studied in the frame of effective field theories. The best constraint on the $H\tau ... More
Effective Lagrangian description of Higgs mediated flavor violating electromagnetic transitions: implications on lepton flavor violationMay 28 2009Higgs mediated flavor violating electromagnetic interactions, induced at the one--loop level by a nondiagonal $Hf_if_j$ vertex, with $f_i$ and $f_j$ charged leptons or quarks, are studied within the context of a completely general effective Yukawa sector ... More
Lax Equations, Singularities and Riemann-Hilbert ProblemsOct 14 2010The existence of singularities of the solution for a class of Lax equations is investigated using a development of the fac- torization method first proposed by Semenov-Tian-Shansky and Reymann [11], [9]. It is shown that the existence of a singularity ... More
Evolution Strategies in Optimization ProblemsSep 07 2007Evolution Strategies are inspired in biology and part of a larger research field known as Evolutionary Algorithms. Those strategies perform a random search in the space of admissible functions, aiming to optimize some given objective function. We show ... More
Heavy neutral pseudoscalar decays into gauge bosons in the Littlest Higgs ModelMar 23 2017We study two-body decays of a new neutral pseudoscalar into gauge bosons within the context of the Littlest Higgs model. Concretely, the $\Phi^P \to WW, VV, gg$ processes induced at the one-loop level, with $V=\gamma, Z$, are considered. Since the branching ... More
Central Limit Theorem for the Excited Random Walk in dimension $d \geq 2$May 04 2007Jun 06 2007We prove that a law of large numbers and a central limit theorem hold for the excited random walk model in every dimension $d \geq 2$.
Khintchine's Theorem with random fractionsAug 09 2017Dec 17 2018We prove versions of Khintchine's Theorem (1924) for approximations by rational numbers whose numerators lie in randomly chosen sets of integers, and we explore the extent to which the monotonicity assumption can be removed. Roughly speaking, we show ... More
Astronomical bounds on future big freeze singularityMay 28 2007Recently it was found that dark energy in the form of phantom generalized Chaplygin gas may lead to a new form of the cosmic doomsday, the big freeze singularity. Like the big rip singularity, the big freeze singularity would also take place at a finite ... More
Cytoskeletal turnover and Myosin contractility drive cell autonomous oscillations in a model of Drosophila Dorsal ClosureFeb 21 2014Mar 13 2014Oscillatory behaviour in force-generating systems is a pervasive phenomenon in cell biology. In this work, we investigate how oscillations in the actomyosin cytoskeleton drive cell shape changes during the process of Dorsal Closure, a morphogenetic event ... More
Non-Abelian black holes in string theoryApr 04 2017Dec 14 2017We study a family of 5-dimensional non-Abelian black holes that can be obtained by adding an instanton field to the well-known D1D5W Abelian black holes. Naively, the non-Abelian fields seem to contribute to the black-hole entropy but not to the mass ... More
Neutrino oscillations from warped flavor symmetry: predictions for long baseline experiments T2K, NOvA and DUNEOct 19 2016Here we study the pattern of neutrino oscillations emerging from a previously proposed warped model construction incorporating $\Delta(27)$ flavor symmetry. In addition to a complete description of fermion masses, the model predicts the lepton mixing ... More
Probing atmospheric mixing and leptonic CP violation in current and future long baseline oscillation experimentsFeb 10 2017Sep 26 2017We perform realistic simulations of the current and future long baseline experiments such as T2K, NO$\nu$A, DUNE and T2HK in order to determine their ultimate potential in probing neutrino oscillation parameters. We quantify the potential of these experiments ... More
Local Conjugacy of Irreducible Hyperbolic Toral AutomorphismsNov 17 2016This paper is dedicated to the conjugacy problem in $GL(n,\Z)$ and its connection with algebraic number theory. This connection may be summed up in the Latimer-MacDuffee-Taussky Theorem, which, in a very broad sense, identifies the conjugacy relation ... More
Automorphisms for skew PBW extensions and skew quantum polynomial ringsNov 19 2013In this work we study the automorphisms of skew $PBW$ extensions and skew quantum polynomials. We use Artamonov's works as reference for getting the principal results about automorphisms for generic skew $PBW$ extensions and generic skew quantum polynomials. ... More
An MDL framework for sparse coding and dictionary learningOct 11 2011The power of sparse signal modeling with learned over-complete dictionaries has been demonstrated in a variety of applications and fields, from signal processing to statistical inference and machine learning. However, the statistical properties of these ... More
Incomplete Generalized Fibonacci and Lucas PolynomialsAug 19 2013In this paper, we define the incomplete h(x)-Fibonacci and h(x)-Lucas polynomials, we study recurrence relations and some properties of these polynomials
Khintchine types of translated coordinate hyperplanesMay 28 2014Jan 14 2015There has been great interest in developing a theory of "Khintchine types" for manifolds embedded in Euclidean space, and considerable progress has been made for curved manifolds. We treat the case of translates of coordinate hyperplanes, decidedly flat ... More
On the multipliers at fixed points of self-maps of the projective planeFeb 09 2019Feb 15 2019This paper deals with holomorphic self-maps of the complex projective plane and the algebraic relations among the eigenvalues of the derivatives at the fixed points. These eigenvalues are constrained by certain index theorems such as the holomorphic Lefschetz ... More
Multifield Dynamics in Higgs-otic InflationMay 01 2015In Higgs-otic inflation a complex neutral scalar combination of the $h^0$ and $H^0$ MSSM Higgs fields plays the role of inflaton in a chaotic fashion. The potential is protected from large trans-Planckian corrections at large inflaton if the system is ... More
Connectivity-Enforcing Hough Transform for the Robust Extraction of Line SegmentsSep 16 2011Global voting schemes based on the Hough transform (HT) have been widely used to robustly detect lines in images. However, since the votes do not take line connectivity into account, these methods do not deal well with cluttered images. In opposition, ... More
Maximizing compression efficiency through block rotationNov 16 2014The Discrete Cosine Transform (DCT) is widely used in lossy image and video compression schemes, e.g., JPEG and MPEG. In this paper, we show that the compression efficiency of the DCT is dependent on the edge directions within a block. In particular, ... More
Resolving the atmospheric octant by an improved measurement of the reactor angleMar 09 2017Jun 28 2017Taking into account the current global information on neutrino oscillation parameters we forecast the capabilities of future long baseline experiments such as DUNE and T2HK in settling the atmospheric octant puzzle. We find that a good measurement of ... More
A gravitating Yang-Mills instantonApr 03 2017Apr 26 2017We present an asymptotically flat, spherically symmetric, static, globally regular and horizonless solution of SU$(2)$-gauged $\mathcal{N}=1,d=5$ supergravity. The SU$(2)$ gauge field is that of the BPST instanton. We argue that this solution, analogous ... More
Various aspects of differential equations having a complete set of independent first integralsJun 13 2011In this paper we study the differential equations in $D\subseteq \R^{2N}$ having a complete set of independent first integrals. In particular we study the case when the first integrals are \[f_\nu=(Ax_\nu+By_\nu)^2+\displaystyle\sum_{j=1}^{N}\dfrac{(x_\nu ... More
Magnetic operations: a little fuzzy physics?Jun 10 2010Dec 20 2010We examine the behaviour of charged particles in homogeneous, constant and/or oscillating magnetic fields in the non-relativistic approximation. A special role of the geometric center of the particle trajectory is elucidated. In quantum case it becomes ... More
An Introduction to Inversion in an EllipseSep 25 2013In this paper we study the inversion in an ellipse and some properties, which generalizes the classical inversion with respect to a circle. We also study the inversion in an ellipse of lines, ellipses and other curves. Finally, we generalize the Pappus ... More
Low-rank data modeling via the Minimum Description Length principleSep 28 2011Robust low-rank matrix estimation is a topic of increasing interest, with promising applications in a variety of fields, from computer vision to data mining and recommender systems. Recent theoretical results establish the ability of such data models ... More
Sparse coding and dictionary learning based on the MDL principleOct 22 2010The power of sparse signal coding with learned dictionaries has been demonstrated in a variety of applications and fields, from signal processing to statistical inference and machine learning. However, the statistical properties of these models, such ... More
The Pascal Rhombus and the Generalized Grand Motzkin PathsNov 14 2015May 04 2016In the present article, we find a closed expression for the entries of the Pascal rhombus. Moreover, we show a relation between the entries of the Pascal rhombus and a family of generalized grand Motzkin paths.
Refining the partition for multifold conic optimization problemsApr 02 2018In this paper we give a unified treatment to different definitions of complementarity partition for a primal-dual pair of linear conic optimization problem.
On Convolved Generalized Fibonacci and Lucas PolynomialsAug 17 2013We define the convolved h(x)-Fibonacci polynomials as an extension of the classical convolved Fibonacci numbers. Then we give some combinatorial formulas involving the h(x)-Fibonacci and h(x)-Lucas polynomials. Moreover we obtain the convolved h(x)-Fibonacci ... More
Isotropic extensions of the vacuum solutions in general relativityJul 22 2011Oct 29 2011In this work, we obtain isotropic extensions of the usual spherically symmetric vacuum geometries in general relativity. Exact and perturbative solutions are derived. The classes of geometries obtained include black holes in compact and noncompact universes, ... More
N=2 Einstein-Yang-Mills' static two-center solutionsOct 15 2014Oct 24 2014We construct bona fide one- and two-center supersymmetric solutions to N=2, d=4 supergravity coupled to SU(2) non-Abelian vector multiplets. The solutions describe black holes and global monopoles alone or in equilibrium with each other and exhibit non-Abelian ... More
Competing interactions and the Lifshitz-type Nonlinear Sigma ModelMay 16 2013Aug 01 2013We establish the equivalence between the continuum limit of the quantum spherical model with competing interactions, which is relevant to the investigation of Lifshitz points, and the O(N) nonlinear sigma model with the addition of higher order spatial ... More
Stochastic Quantization of the Spherical Model and SupersymmetryNov 21 2012Sep 20 2013We use the stochastic quantization method to construct a supersymmetric version of the quantum spherical model. This is based on the equivalence between the Brownian motion described by a Langevin equation and the supersymmetric quantum mechanics, which ... More
Nature of short high amplitude pulses in a periodic dissipative laminate metamaterialJun 02 2015We study the evolution of high amplitude stress pulses in periodic dissipative laminates taking into account the nonlinear constitutive equations of the components and their dissipative behavior. Aluminum and Tungsten laminate was taken as an example ... More
RedThreads: An Interface for Application-level Fault Detection/Correction through Adaptive Redundant MultithreadingOct 06 2016In the presence of accelerated fault rates, which are projected to be the norm on future exascale systems, it will become increasingly difficult for high-performance computing (HPC) applications to accomplish useful computation. Due to the fault-oblivious ... More
The small black hole illusionAug 30 2018Small black holes in string theory are characterized by a classically singular horizon with vanishing Bekenstein-Hawking entropy. It has been argued that higher-curvature corrections resolve the horizon and that the associated Wald entropy is in agreement ... More
$α'$-corrected black holes in String TheoryMar 05 2018May 11 2018We consider the well-known solution of the Heterotic Superstring effective action to zeroth order in $\alpha'$ that describes the intersection of a fundamental string with momentum and a solitonic 5-brane and which gives a 3-charge, static, extremal, ... More
An Information Theoretic Feature Selection Framework for Big Data under Apache SparkOct 13 2016With the advent of extremely high dimensional datasets, dimensionality reduction techniques are becoming mandatory. Among many techniques, feature selection has been growing in interest as an important tool to identify relevant features on huge datasets ... More
Ultra-recursive sequencesFeb 05 2019We study a new type of sequences whose elements are defined in terms of the position, sign and magnitude of another element of the sequence. The name ultra-recursive comes from the fact that these sequences possess terms that are generated adding either ... More
On the multipliers at fixed points of self-maps of the projective planeFeb 09 2019This paper deals with holomorphic self-maps of the complex projective plane and the algebraic relations among the eigenvalues of the derivatives at the fixed points. These eigenvalues are constrained by certain index theorems such as the holomorphic Lefschetz ... More
A characterization of bad approximabilityJul 03 2017Jan 22 2018We show that badly approximable vectors are exactly those that cannot, for any inhomogeneous parameter, be inhomogeneously approximated at every monotone divergent rate. This implies in particular that Kurzweil's Theorem cannot be restricted to any points ... More
A Rule-Based Approach For Aligning Japanese-Spanish Sentences From A Comparable CorporaNov 19 2012The performance of a Statistical Machine Translation System (SMT) system is proportionally directed to the quality and length of the parallel corpus it uses. However for some pair of languages there is a considerable lack of them. The long term goal is ... More
A $q$-analogue of the Biperiodic Fibonacci SequenceJan 23 2015The Fibonacci sequence has been generalized in many ways. One of them is defined by the relation $t_n=at_{n-1}+t_{n-2}$ if $n$ is even, $t_n=bt_{n-1}+t_{n-2}$ if $n$ is odd, with initial values $t_0=0$ and $t_1=1$, where $a$ and $b$ are positive integers. ... More
Applications in Enumerative Combinatorics of Infinite Weighted Automata and GraphsOct 09 2013Dec 25 2013In this paper we studied infinite weighted automata and a general methodology to solve a wide variety of classical lattice path counting problems in an uniform way. This counting problems are related to Dyck paths, Motzkin paths and some generalizations. ... More
D-ADMM: A Communication-Efficient Distributed Algorithm For Separable OptimizationFeb 13 2012Apr 22 2013We propose a distributed algorithm, named Distributed Alternating Direction Method of Multipliers (D-ADMM), for solving separable optimization problems in networks of interconnected nodes or agents. In a separable optimization problem there is a private ... More
Recurrence to shrinking targets on typical self-affine fractalsSep 26 2014Oct 19 2015We explore the problem of finding the Hausdorff dimension of the set of points that recur to shrinking targets on a self-affine fractal. To be exact, we study the dimension of a certain related symbolic recurrence set. In many cases this set is equivalent ... More
Magnetic fields and differential rotation on the pre-main sequence III: The early-G star HD 106506Feb 17 2011We present photometry and spectropolarimetry of the pre-main sequence star HD 106506. A photometric rotational period of ~1.416 +/- 0.133 days has been derived using observations at Mount Kent Observatory (MKO). Spectropolarimetric data taken at the 3.9-m ... More
The Mid-Infrared Colors of the ISM and Extended Sources at the Galactic CenterApr 28 2008A mid-infrared (3.6-8 um) survey of the Galactic Center has been carried out with the IRAC instrument on the Spitzer Space Telescope. This survey covers the central 2x1.4 degree (~280x200 pc) of the Galaxy. At 3.6 and 4.5 um the emission is dominated ... More
A Discrete Algorithm to the Calculus of VariationsMar 03 2010A numerical study of an algorithm proposed by Gusein Guseinov, which determines approximations to the optimal solution of problems of calculus of variations using two discretizations and correspondent Euler-Lagrange equations, is investigated. The results ... More
A non-classical class of variational problemsNov 02 2009We study a new non-classical class of variational problems that is motivated by some recent research on the non-linear revenue problem in the field of economics. This class of problem can be set up as a maximising problem in the Calculus of Variations ... More
On the Möbius function of the locally finite poset associated with a numerical semigroupSep 10 2012Mar 31 2016Let $S$ be a numerical semigroup and let $\left(\mathbb{Z},\leqslant\_S\right)$ be the (locally finite) poset induced by $S$ on the set of integers $\mathbb{Z}$ defined by $x \leqslant\_S y$ if and only if $y-x\in S$ for all integers $x$ and $y$. In this ... More
Large scale evaluation of differences between network-based and pairwise sequence-alignment-based methods of dendrogram reconstructionSep 26 2017Dendrograms are a way to represent evolutionary relationships between organisms. Nowadays, these are inferred based on the comparison of genes or protein sequences by taking into account their differences and similarities. The genetic material of choice ... More
struc2vec: Learning Node Representations from Structural IdentityApr 11 2017Jul 03 2017Structural identity is a concept of symmetry in which network nodes are identified according to the network structure and their relationship to other nodes. Structural identity has been studied in theory and practice over the past decades, but only recently ... More
Logarithmic Wind Profile: A Stability Wind Shear TermMay 20 2014A stability wind shear term of logarithmic wind profile based on the terms of turbulent kinetic energy equation is proposed. The fraction influenced by thermal stratification is considered in the shear production term. This thermally affected shear is ... More
Cornering the revamped BMV model with neutrino oscillation dataAug 10 2017Using the latest global determination of neutrino oscillation parameters from~\cite{deSalas:2017kay} we examine the status of the simplest revamped version of the BMV (Babu-Ma-Valle) model, proposed in~\cite{Morisi:2013qna}. The model predicts a striking ... More
An Approach to Static Performance Guarantees for Programs with Run-time ChecksApr 06 2018Instrumenting programs for performing run-time checking of properties, such as regular shapes, is a common and useful technique that helps programmers detect incorrect program behaviors. This is specially true in dynamic languages such as Prolog. However, ... More
Improving Community Detection by Mining Social InteractionsOct 03 2018Oct 05 2018Social relationships can be divided into different classes based on the regularity with which they occur and the similarity among them. Thus, rare and somewhat similar relationships are random and cause noise in a social network, thus hiding the actual ... More
Group Mobility: Detection, Tracking and CharacterizationDec 15 2015In the era of mobile computing, understanding human mobility patterns is crucial in order to better design protocols and applications. Many studies focus on different aspects of human mobility such as people's points of interests, routes, traffic, individual ... More
Shadows of Kerr black holes with scalar hairAug 31 2015Nov 07 2015Using backwards ray tracing, we study the shadows of Kerr black holes with scalar hair (KBHsSH). KBHsSH interpolate continuously between Kerr BHs and boson stars (BSs), so we start by investigating the lensing of light due to BSs. Moving from the weak ... More