Results for "Vlad Niculae"

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Sparse Sequence-to-Sequence ModelsMay 14 2019Sequence-to-sequence models are a powerful workhorse of NLP. Most variants employ a softmax transformation in both their attention mechanism and output layer, leading to dense alignments and strictly positive output probabilities. This density is wasteful, ... More
Towards Dynamic Computation Graphs via Sparse Latent StructureSep 03 2018Deep NLP models benefit from underlying structures in the data---e.g., parse trees---typically extracted using off-the-shelf parsers. Recent attempts to jointly learn the latent structure encounter a tradeoff: either make factorization assumptions that ... More
Winning Arguments: Interaction Dynamics and Persuasion Strategies in Good-faith Online DiscussionsFeb 02 2016Feb 06 2016Changing someone's opinion is arguably one of the most important challenges of social interaction. The underlying process proves difficult to study: it is hard to know how someone's opinions are formed and whether and how someone's views shift. Fortunately, ... More
A Regularized Framework for Sparse and Structured Neural AttentionMay 22 2017Feb 23 2019Modern neural networks are often augmented with an attention mechanism, which tells the network where to focus within the input. We propose in this paper a new framework for sparse and structured attention, building upon a smoothed max operator. We show ... More
Conversational Markers of Constructive DiscussionsApr 25 2016Group discussions are essential for organizing every aspect of modern life, from faculty meetings to senate debates, from grant review panels to papal conclaves. While costly in terms of time and organization effort, group discussions are commonly seen ... More
Argument Mining with Structured SVMs and RNNsApr 23 2017We propose a novel factor graph model for argument mining, designed for settings in which the argumentative relations in a document do not necessarily form a tree structure. (This is the case in over 20% of the web comments dataset we release.) Our model ... More
Learning with Fenchel-Young LossesJan 08 2019Over the past decades, numerous loss functions have been been proposed for a variety of supervised learning tasks, including regression, classification, ranking, and more generally structured prediction. Understanding the core principles and theoretical ... More
SparseMAP: Differentiable Sparse Structured InferenceFeb 12 2018Jun 20 2018Structured prediction requires searching over a combinatorial number of structures. To tackle it, we introduce SparseMAP: a new method for sparse structured inference, and its natural loss function. SparseMAP automatically selects only a few global structures: ... More
Learning Classifiers with Fenchel-Young Losses: Generalized Entropies, Margins, and AlgorithmsMay 24 2018Feb 22 2019This paper studies Fenchel-Young losses, a generic way to construct convex loss functions from a regularization function. We analyze their properties in depth, showing that they unify many well-known loss functions and allow to create useful new ones ... More
Multi-output Polynomial Networks and Factorization MachinesMay 22 2017Nov 04 2017Factorization machines and polynomial networks are supervised polynomial models based on an efficient low-rank decomposition. We extend these models to the multi-output setting, i.e., for learning vector-valued functions, with application to multi-class ... More
Linguistic Harbingers of Betrayal: A Case Study on an Online Strategy GameJun 15 2015Interpersonal relations are fickle, with close friendships often dissolving into enmity. In this work, we explore linguistic cues that presage such transitions by studying dyadic interactions in an online strategy game where players form alliances and ... More
QUOTUS: The Structure of Political Media Coverage as Revealed by Quoting PatternsApr 06 2015Given the extremely large pool of events and stories available, media outlets need to focus on a subset of issues and aspects to convey to their audience. Outlets are often accused of exhibiting a systematic bias in this selection process, with different ... More
An Infinitesimal $p$-adic Multiplicative Manin-Mumford ConjectureJul 05 2016Our results concern analytic functions on the open unit $p$-adic poly-disc in $\mathbb{C}^n_p$ centered at the multiplicative unit and we prove that such functions only vanish at finitely many $n$-tuples of roots of unity $(\zeta_1-1,\ldots,\zeta_n-1)$ ... More
Lower bounds for the density of locally elliptic Itô processesFeb 28 2007We give lower bounds for the density $p_T(x,y)$ of the law of $X_t$, the solution of $dX_t=\sigma (X_t) dB_t+b(X_t) dt,X_0=x,$ under the following local ellipticity hypothesis: there exists a deterministic differentiable curve $x_t, 0\leq t\leq T$, such ... More
Trajectory trapping and the evolution of drift turbulence beyond the quasilinear stageSep 10 2012Test modes on turbulent magnetized plasmas are studied taking into account the ion trapping that characterizes the E x B drift in the background turbulence. We show that trappyng provides the physical mechanism for the formation of large scale potential ... More
A finiteness result for $p$-adic families of Bianchi modular formsFeb 08 2019We study $p$-adic families of cohomological automorphic forms for ${\mathrm{GL}}(2)$ over imaginary quadratic fields and prove that families interpolating a Zariski-dense set of classical cuspidal automorphic forms only occur under very restrictive conditions. ... More
An Infinitesimal $p$-adic Multiplicative Manin-Mumford ConjectureJul 05 2016Dec 13 2018Our results concern analytic functions on the open unit $p$-adic poly-disc in $\mathbb{C}^n_p$ centered at the multiplicative unit and we prove that such functions only vanish at finitely many $n$-tuples of roots of unity $(\zeta_1-1,\ldots,\zeta_n-1)$ ... More
On Area Comparison and Rigidity Involving the Scalar CurvatureSep 04 2013We prove a splitting theorem for Riemannian n-manifolds with scalar curvature bounded below by a negative constant and containing certain area-minimising hypersurfaces (Theorem 3). Thus we generalise [25,Theorem 3] by Nunes. This splitting result follows ... More
Aging processes in reversible reaction-diffusion systemsApr 11 2008Reversible reaction-diffusion systems display anomalous dynamics characterized by a power-law relaxation toward stationarity. In this paper we study in the aging regime the nonequilibrium dynamical properties of some model systems with reversible reactions. ... More
Almost global existence for the Prandtl boundary layer equationsFeb 15 2015Sep 25 2015We consider the Prandtl boundary layer equations on the half plane, with initial datum that lies in a weighted $H^1$ space with respect to the normal variable, and is real-analytic with respect to the tangential variable. The boundary trace of the horizontal ... More
Geometrical aspects of the interaction between expanding clouds and environmentAug 18 2015This work is intended to be a contribution to the study of the morphology of the rising convective columns, for a better representation of the processes of entrainment and detrainment. We examine technical methods for the description of the interface ... More
Field theoretical prediction of a property of the tropical cycloneOct 10 2013Apr 12 2014The large scale atmospheric vortices (tropical cyclones, tornadoes) are complex physical systems combining thermodynamics and fluid-mechanical processes. The well known tendency of vorticity to self-organization, an universal property of the two-dimensional ... More
Scaling laws for the tropical cyclone derived from the stationary atmospheric vortex equationApr 07 2006Apr 03 2007In a two-dimensional model of the planetary atmosphere the compressible convective flow of vorticity represents a strong nonlinearity able to drive the fluid toward a quasi-coherent vortical pattern. This is similar to the highly organised motion generated ... More
Effects of the resonant magnetic perturbation on turbulent transportDec 02 2015The effects of the resonant magnetic perturbations (RMPs) on the turbulent transport are analyzed in the framework of the test particle approach using a semi-analytical method. The normalized RMP amplitude $P_{b}$ extends on a large range, from the present ... More
Trajectory structures and transportFeb 29 2004The special problem of transport in 2-dimensional divergence-free stochastic velocity fields is studied by developing a statistical approach, the nested subensemble method. The nonlinear process of trapping determined by such fields generates trajectory ... More
Coherent structures in a turbulent environmentFeb 13 2001A systematic method is proposed for the determination of the statistical properties of a field consisting of a coherent structure interacting with turbulent linear waves. The explicit expression of the generating functional of the correlations is obtained, ... More
Integration by parts formula with respect to jump times for stochastic differential equationsApr 19 2010We establish an integration by parts formula based on jumps times in an abstract framework in order to study the regularity of the law for processes solution of stochastic differential equations with jumps.
Defining the Delays of the Asynchronous CircuitsFeb 17 2004We define the delays of a circuit, as well as the properties of determinism, order, time invariance, constancy, symmetry and the serial connection.
Towards a Mathematical Theory of the Delays of the Asynchronous CircuitsFeb 17 2004The inequations of the delays of the asynchronous circuits are written, by making use of pseudo-Boolean differential calculus. We consider these efforts to be a possible starting point in the semi-formalized reconstruction of the digital electrical engineering ... More
Introductory Topics in Distributions over Binary Test FunctionsOct 31 2001We note with B2 the Boole algebra with two elements. We define for the R->B2 functions the limits, the derivatives, the differentiability, the test functions, the integrals. We also define the distributions over the space of these test functions, the ... More
Real Time Models of the Asynchronous Circuits: The Delay TheoryDec 17 2004The chapter from the book introduces the delay theory, whose purpose is the modeling of the asynchronous circuits from digital electrical engineering with ordinary and differential pseudo-boolean equations.
Results of the four-wave kinetic integral computation for spectra of special forms. The case of Zakharov spectraJan 11 2014With the aim to show explicitly the non stationarity of the Zakharov spectra, obtained analytically as the stationary solution of the four-wave kinetic equation for stochastic nonlinear surface gravity waves[1,2], we have calculated directly the proper ... More
Analyticity and Gevrey-class regularity for the second-grade fluid equationsDec 07 2009We address the global persistence of analyticity and Gevrey-class regularity of solutions to the two and three-dimensional visco-elastic second-grade fluid equations. We obtain an explicit novel lower bound on the radius of analyticity of the solutions ... More
Detecting Singleton Review Spammers Using Semantic SimilaritySep 09 2016Online reviews have increasingly become a very important resource for consumers when making purchases. Though it is becoming more and more difficult for people to make well-informed buying decisions without being deceived by fake reviews. Prior works ... More
Topological Entropy and Diffeomorphisms of Surfaces with Wandering DomainsOct 07 2009Let $M$ be a closed surface and $f$ a diffeomorphism of $M$. A diffeomorphism is said to permute a dense collection of domains, if the union of the domains are dense and the iterates of any one domain are mutually disjoint. In this note, we show that ... More
Higher moments of arithmetic functions in short intervals: a geometric perspectiveApr 07 2016Dec 01 2016We study the geometry associated to the distribution of certain arithmetic functions, including the von Mangoldt function and the M\"obius function, in short intervals of polynomials over a finite field $\mathbb{F}_q$. Using the Grothendieck-Lefschetz ... More
Transfer of regularity for Markov semigroupsMay 15 2019We study the regularity of a Markov semigroup $(P_t)_{t>0}$, that is, when $P_t(x,dy)=p_t(x,y)dy$ for a suitable smooth function $p_t(x,y)$. This is done by transferring the regularity from an approximating Markov semigroup sequence $(P^n_t)_{t>0}$, $n\in\mathbb{N}$, ... More
The filamentation of the laser beam as a labyrinth instabilityJun 13 2015At incident powers much higher than the threshold for filamentation a pulse from a high-power laser generates in the transversal plane a complex structure. It consists of randomly meandering stripes defining connected regions where the field intensity ... More
Helicity fluctuation, generation of linking number and effect on resistivityDec 28 2006The energy of the stochastic magnetic field is bounded from below by a topological quantity expressing the degree of linkage of the field lines. When the bound is saturated one can assume that the storage of a certain magnetic energy requires a minimal ... More
Exact vortex solution of the Jacobs-Rebbi equation for ideal fluidsOct 06 2003The Jacobs-Rebbi equation arises in many contexts where vortical motion in two-dimensional ideal media is investigated. Alternatively, it can be derived in the Abelian Higgs field theory. It is considered non-integrable and numerical solutions have been ... More
On the nature of intermittency in weakly dissipative systemsAug 08 2002We propose a new perspective on the intermittency in weakly dissipative systems. It is focused on the elementary (burst-like) event separating states with different properties. This event is seen as a real-space-time manifestation of an instanton connecting ... More
Effect of density changes on tokamak plasma confinementFeb 21 2015Jul 10 2015A change of the particle density (by gas puff, pellets or impurity seeding) during the plasma discharge in tokamak produces a radial current and implicitly a torque and rotation that can modify the state of confinement. After ionization the newly born ... More
Larmor radius effects on impurity transport in turbulent plasmasAug 05 2004Test particle transport determined by the Lorentz force in turbulent magnetized plasmas is studied. The time dependent diffusion coefficient, valid for the whole range of parameters, is obtained by developing the decorrelation trajectory method. The effects ... More
The equations of the ideal latchesApr 05 2008The latches are simple circuits with feedback from the digital electrical engineering. We have included in our work the C element of Muller, the RS latch, the clocked RS latch, the D latch and also circuits containing two interconnected latches: the edge ... More
Asynchronous pseudo-systemsMay 14 2005The paper introduces the concept of asynchronous pseudo-system. Its purpose is to correct/generalize/continue the study of the asynchronous systems (the models of the asynchronous circuits) that has been started in [1], [2].
The equations of the ideal latchesNov 05 2004Nov 08 2004The latches are simple circuits with feedback from the digital electrical engineering. We have included in our work the C element of Muller, the RS latch, the clocked RS latch, the D latch and also circuits containing two interconnected latches: the edge ... More
On the Inertia of the Asynchronous CircuitsFeb 17 2004We present the bounded delays, the absolute inertia and the relative inertia.
Introductory Topics in Binary Set FunctionsOct 31 2001Let X be a non-empty set and U a ring of subsets of X. The countable additive functions U->{0,1} are called measures. The paper gives some definitions (derivable measures, the Lebesgue-Stieltjes measures) and properties of these functions, its purpose ... More
Faster Fair Solution for the Reader-Writer ProblemSep 18 2013A fast fair solution for Reader-Writer Problem is presented.
On the basins of attraction of the regular autonomous asynchronous systemsJun 20 2012Jul 20 2013The Boolean autonomous dynamical systems, also called regular autonomous asynchronous systems are systems whose 'vector field' is a function {\Phi}:{0,1}^{n}{\to}{0,1}^{n} and time is discrete or continuous. While the synchronous systems have their coordinate ... More
An Asynchronous Automata Approach to the Semantics of Temporal LogicOct 31 2001The paper presents the differential equations that characterize an asynchronous automaton and gives their solution x:R->{0,1}x...x{0,1}. Remarks are made on the connection between the continuous time and the discrete time of the approach. The continuous ... More
Universal regular autonomous asynchronous systems: omega-limit sets, invariance and basins of attractionDec 28 2010The asynchronous systems are the non-deterministic real time-binary models of the asynchronous circuits from electrical engineering. Autonomy means that the circuits and their models have no input. Regularity means analogies with the dynamical systems, ... More
Applications of the Differential Calculus in the Study of the Timed Automata: the Inertial Delay BufferOct 31 2001We write the relations that characterize the simpliest timed automaton, the inertial delay buffer, in two versions: the non-deterministic and the deterministic one, by making use of the derivatives of the R->{0,1} functions.
Convex integration and phenomenologies in turbulenceJan 25 2019Apr 05 2019In this review article we discuss a number of recent results concerning wild weak solutions of the incompressible Euler and Navier-Stokes equations. These results build on the groundbreaking works of De Lellis and Sz\'ekelyhidi Jr., who extended Nash's ... More
Binary periodic signals and flowsNov 21 2014The concept of boolean autonomous deterministic regular asynchronous system has its origin in switching theory, the theory of modeling the switching circuits from the digital electrical engineering. The attribute boolean vaguely refers to the Boole algebra ... More
Universal Regular Autonomous Asynchronous Systems: Fixed Points, Equivalencies and Dynamic BifurcationsJun 20 2012Jul 20 2013The asynchronous systems are the non-deterministic models of the asynchronous circuits from the digital electrical engineering. In the autonomous version, such a system is a set of functions x:R{\to}{0,1}^{n} called states (R is the time set). If an asynchronous ... More
Argument Identification in Public Comments from eRulemakingMay 02 2019Administrative agencies in the United States receive millions of comments each year concerning proposed agency actions during the eRulemaking process. These comments represent a diversity of arguments in support and opposition of the proposals. While ... More
Riesz transform and integration by parts formulas for random variablesNov 13 2009Apr 29 2010We use integration by parts formulas to give estimates for the $L^p$ norm of the Riesz transform. This is motivated by the representation formula for conditional expectations of functionals on the Wiener space already given in Malliavin and Thalmaier. ... More
Holder continuity for a drift-diffusion equation with pressureMar 19 2011We address the persistence of H\"older continuity for weak solutions of the linear drift-diffusion equation with nonlocal pressure \[ u_t + b \cdot \grad u - \lap u = \grad p,\qquad \grad\cdot u =0 \] on $[0,\infty) \times \R^{n}$, with $n \geq 2$. The ... More
Total variation distance between stochastic polynomials and invariance principlesMay 15 2017The goal of this paper is to estimate the total variation distance between two general stochastic polynomials. As a consequence one obtains an invariance principle for such polynomials. This generalizes known results concerning the total variation distance ... More
Regularity of probability laws by using an interpolation methodOct 31 2012We study the problem of the existence and regularity of a probability density in an abstract framework based on a "balancing" with approximating absolutely continuous laws. Typically, the absolutely continuous property for the approximating laws can be ... More
Hasq Hash ChainsDec 14 2014This paper describes a particular hash-based records linking chain scheme. This scheme is simple conceptually and easy to implement in software. It allows for a simple and secure way to transfer ownership of digital objects between peers.
Field theoretical formulation of the asymptotic relaxation states of two-dimensional ideal fluidsDec 23 2013Sep 18 2014The ideal incompressible fluid in two dimensions (Euler fluid) evolves at relaxation from turbulent states to highly coherent states of flow. For the case of double spatial periodicity and zero total vorticity it is known that the streamfunction verifies ... More
The role of convective structures in the poloidal and toroidal rotation in tokamakJan 05 2013Jun 19 2013The connection between the poloidal and the toroidal rotation of plasma in tokamak is important for the high confinement regimes, in particular in reactor regime. The sudden onset of closed convection structures in the poloidal section, due to the baroclinic ... More
The asymptotic quasi-stationary states of the two-dimensional magnetically confined plasma and of the planetary atmosphereJan 06 2005Nov 21 2007We derive the differential equation governing the asymptotic quasi-stationary states of the two dimensional plasma immersed in a strong confining magnetic field and of the planetary atmosphere. These two systems are related by the property that there ... More
Fluctuation of the ambipolar equilibrium in magnetic perturbationsJun 18 2002We draw attention on the fast oscillatory deviations from the residual non-ambipolarity in the case where electrons are driven by strong magnetic perturbations.
Multipartite Entanglement Evolution Under Separable OperationsMay 11 2012Nov 07 2012We study how multi-partite entanglement evolves under the paradigm of separable operations, which include the local operations and classical communication (LOCC) as a special case. We prove that the average "decay" of entanglement induced by a separable ... More
Higher moments of arithmetic functions in short intervals: a geometric perspectiveApr 07 2016We study the distribution in short intervals of certain arithmetic functions, including the von Mangoldt function and the M\"obius function, on polynomials over a finite field $\mathbb{F}_q$. Using the Grothendieck-Lefschetz trace formula, we reinterpret ... More
The intersection and the union of the asynchronous systemsOct 20 2006The asynchronous systems $f$ are the models of the asynchronous circuits from digital electrical engineering. They are multi-valued functions that associate to each input $u:\mathbf{R}\to \{0,1\}^{m}$ a set of states $x\in f(u),$ where $x:\mathbf{R}\to ... More
Some first thoughts on the stability of the asynchronous systemsOct 29 2004The (non-initialized, non-deterministic) asynchronous systems (in the input-output sense) are multi-valued functions from m-dimensional signals to sets of n-dimensional signals, the concept being inspired by the modeling of the asynchronous circuits. ... More
Random and quasi-coherent aspects in particle motion and their effects on transport and turbulence evolutionNov 25 2016The quasi-coherent effects in two-dimensional incompressible turbulence are analyzed starting from the test particle trajectories. They can acquire coherent aspects when the stochastic potential has slow time variation and the motion is not strongly perturbed. ... More
Vapor-deposited non-crystalline phase vs ordinary glasses and supercooled liquids: evidence for significant thermodynamic and kinetic differencesOct 31 2014Vapor deposition of molecules on a substrate often results in glassy materials of high kinetic stability and low enthalpy. The extraordinary properties of such glasses are attributed to high rates of surface diffusion during sample deposition, which makes ... More
Enthalpy and high temperature relaxation kinetics of stable vapor-deposited glasses of tolueneJun 18 2014Stable non-crystalline toluene films of micrometer and nanometer thicknesses were grown by vapor deposition at distinct rates and probed by Fast Scanning Calorimetry. Fast scanning calorimetry is shown to be extremely sensitive to the structure of the ... More
The Delay-Insensitivity, the Hazard-Freedom, the Semi-Modularity and the Technical Condition of Good Running of the Discrete Time Asynchronous AutomataOct 31 2001The paper studies some important properties of the asynchronous (=timed) automata: the delay-insensitivity, the hazard-freedom, the semi-modularity and the technical condition of good running. Time is discrete.
Selected Topics in Asynchronous AutomataOct 31 2001The paper is concerned with defining the electrical signals and their models. The delays are discussed, the asynchronous automata - which are the models of the asynchronous circuits - and the examples of the clock generator and of the R-S latch are given. ... More
On the serial connection of the regular asynchronous systemsJun 20 2012The asynchronous systems f are multi-valued functions, representing the non-deterministic models of the asynchronous circuits from the digital electrical engineering. In real time, they map an 'admissible input' function u:R\rightarrow{0,1}^{m} to a set ... More
On the distance between probability density functionsNov 29 2013We give estimates of the distance between the densities of the laws of two functionals $F$ and $G$ on the Wiener space in terms of the Malliavin-Sobolev norm of $F-G.$ We actually consider a more general framework which allows one to treat with similar ... More
An Invariance Principle for Stochastic Series II. Non Gaussian LimitsJul 13 2016We study the convergence in total variation distance for series of the form $$ S_{N}(c,Z)=\sum_{l=1}^{N}\sum_{i_{1}<\cdots<i_{l}}c(i_{1},...,i_{l})Z_{i_{1}}\cdots Z_{i_{l}}, $$ where $Z_{k},k\in {\mathbb{N}}$ are independent centered random variables ... More
Global well-posedness for an advection-diffusion equation arising in magneto-geostrophic dynamicsJul 07 2010Feb 04 2011We use De Giorgi techniques to prove H\"older continuity of weak solutions to a class of drift-diffusion equations, with $L^2$ initial data and divergence free drift velocity that lies in $L_{t}^{\infty}BMO_{x}^{-1}$. We apply this result to prove global ... More
Equivalence of time-domain inverse problems and boundary spectral problemsFeb 22 2002We consider inverse problems for wave, heat and Schr\"odinger-type operators and corresponding spectral problems on domains of ${\bf R}^n$ and compact manifolds. Also, we study inverse problems where coefficients of partial differential operator have ... More
A MHD invariant and the confinement regimes in TokamakDec 15 2015Jul 18 2016Fundamental Lagrangian, frozen-in and topological invariants can be useful to explain systematic connections between plasma parameters. At high plasma temperature the dissipation is small and the robust invariances are manifested. We invoke a frozen-in ... More
Physical aspects of the field-theoretical description of two-dimensional ideal fluidsDec 31 2009The two-dimensional ideal (Euler) fluids can be described by the classical fields of streamfunction, velocity and vorticity and, in an equivalent manner, by a model of discrete point-like vortices interacting in plane by a self-generated long-range potential. ... More
Field theoretical approach to the description of the coherent structures in 2D fluids and plasmasSep 14 2009Jan 26 2010Evolving from turbulent states the 2D fluids and the plasmas reach states characterized by a high degree of order, consisting of few vortices. These asymptotic states represent a small subset in the space of functions and are characterised by properties ... More
Statistical properties of an ensemble of vortices interacting with a turbulent fieldJun 10 2005Sep 22 2005We develop an analytical formalism to determine the statistical properties of a system consisting of an ensemble of vortices with random position in plane interacting with a turbulent field. We calculate the generating functional by path-integral methods. ... More
Describing two-dimensional vortical flows : the typhoon caseMar 18 2005Mar 31 2005We present results of a numerical study of the differential equation governing the stationary states of the two-dimensional planetary atmosphere and magnetized plasma (within the Charney Hasegawa Mima model). The most strinking result is that the equation ... More
Soliton self-modulation of the turbulence amplitude and plasma rotationApr 17 2002May 29 2002The space-uniform amplitude envelope of the Ion Temperature Gradient driven turbulence is unstable to small perturbations and evolves to nonuniform, soliton-like modulated profiles. The induced poloidal asymmetry of the transport fluxes can generate spontaneous ... More
An analogy between optical turbulence and activator-inhibitor dynamicsJul 18 2016The propagation of laser beams through madia with cubic nonlinear polarization is part of a wide range of practical applications. The processes that are involved are at the limit of extreme (cuasi-singular) concentration of intensity and the transversal ... More
A model for the reversal of the toroidal rotation in tokamakFeb 20 2012The transition from toroidal counter- to co- rotation in the core plasma has been observed at L to H transition in several tokamaks. Spontaneous reversal has also been observed in TCV beyond a threshold in the density. We develop a model based on the ... More
Examples of Models of the Asynchronous CircuitsFeb 17 2004We define the delays of a circuit, as well as the properties of determinism, order, time invariance, constancy, symmetry and the serial connection.
Topics in asynchronous systemsSep 13 2004In the paper we define and characterize the asynchronous systems from the point of view of their autonomy, determinism, order, non-anticipation, time invariance, symmetry, stability and other important properties. The study is inspired by the models of ... More
Proceedings Second International Workshop on Algebraic Methods in Model-based Software EngineeringJun 29 2011Over the past years there has been quite a lot of activity in the algebraic community about using algebraic methods for providing support to model-driven software engineering. The aim of this workshop is to gather researchers working on the development ... More
Nonuniqueness of weak solutions to the Navier-Stokes equationSep 28 2017Oct 11 2018For initial datum of finite kinetic energy, Leray has proven in 1934 that there exists at least one global in time finite energy weak solution of the 3D Navier-Stokes equations. In this paper we prove that weak solutions of the 3D Navier-Stokes equations ... More
Defining the symmetry of the universal semi-regular autonomous asynchronous systemsJun 20 2012Jul 20 2013The regular autonomous asynchronous systems are the non-deterministic Boolean dynamical systems and universality means the greatest in the sense of the inclusion. The paper gives four definitions of symmetry of these systems in a slightly more general ... More
The dependence on the initial states and the transitivity of the regular autonomous asynchronous systemsDec 28 2010The asynchronous systems are non-deterministic real time, binary valued models of the asynchronous circuits from electronics. Autonomy means that there is no input and regularity means analogies with the (real) dynamical systems. We introduce the concepts ... More
The decomposition of the regular asynchronous systems as parallel connection of regular asynchronous systemsJun 20 2012The asynchronous systems are the non-deterministic models of the asynchronous circuits from the digital electrical engineering, where non-determinism is a consequence of the fact that modelling is made in the presence of unknown and variable parameters. ... More
Binary signals: a note on the prime period of a pointDec 22 2012The 'nice' $x:\mathbf{R}\rightarrow\{0,1\}^{n}$ functions from the asynchronous systems theory are called signals. The periodicity of a point of the orbit of the signal x is defined and we give a note on the existence of the prime period.
Argument Identification in Public Comments from eRulemakingMay 02 2019May 14 2019Administrative agencies in the United States receive millions of comments each year concerning proposed agency actions during the eRulemaking process. These comments represent a diversity of arguments in support and opposition of the proposals. While ... More
Rare Events Statistics in Reaction--Diffusion SystemsApr 09 2004Apr 20 2004We develop an efficient method to calculate probabilities of large deviations from the typical behavior (rare events) in reaction--diffusion systems. The method is based on a semiclassical treatment of underlying "quantum" Hamiltonian, encoding the system's ... More
On the analyticity and Gevrey class regularity up to the boundary for the Euler EquationsJul 13 2010We consider the Euler equations in a three-dimensional Gevrey-class bounded domain. Using Lagrangian coordinates we obtain the Gevrey-class persistence of the solution, up to the boundary, with an explicit estimate on the rate of decay of the Gevrey-class ... More
On a transport equation with nonlocal driftAug 05 2014In \cite{CordobaCordobaFontelos05}, C\'ordoba, C\'ordoba, and Fontelos proved that for some initial data, the following nonlocal-drift variant of the 1D Burgers equation does not have global classical solutions \[ \partial_t \theta +u \; \partial_x \theta ... More