Results for "Remi Soummer"

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Apodized Pupil Lyot Coronagraphs for Arbitrary Telescope AperturesDec 09 2004In the context of high dynamic range imaging, this study presents a breakthrough for the understanding of Apodized Pupil Lyot Coronagraphs, making them available for arbitrary aperture shapes. These new solutions find immediate application in current, ... More
High-contrast Imager for Complex Aperture Telescopes (HiCAT): 6. Software Control Infrastructure and CalibrationMar 07 2019High contrast imaging using coronagraphy is one of the main avenues to enable the search for life on extrasolar Earth analogs. The HiCAT testbed aims to demonstrate coronagraphy and wavefront control for segmented on-axis space telescopes as envisioned ... More
New Completeness Methods for Estimating Exoplanet Discoveries by Direct DetectionMar 24 2010We report new methods for evaluating realistic observing programs that search stars for planets by direct imaging, where observations are selected from an optimized star list, and where stars can be observed multiple times. We show how these methods bring ... More
Phase-Retrieval-Based Wavefront Metrology for High Contrast CoronagraphyMar 05 2019We discuss the use of parametric phase-diverse phase retrieval as an in-situ high-fidelity wavefront measurement method to characterize and optimize the transmitted wavefront of a high-contrast coronagraphic instrument. We apply our method to correct ... More
Detection and Characterization of Exoplanets and Disks using Projections on Karhunen-Loeve EigenimagesJul 17 2012We describe a new method to achieve point spread function (PSF) subtractions for high- contrast imaging using Principal Component Analysis (PCA) that is applicable to both point sources or extended objects (disks). Assuming a library of reference PSFs, ... More
Shaped pupil design for the Gemini Planet ImagerMay 11 2009The Gemini Planet Imager (GPI) is an instrument designed for the Gemini South telescope to image young Jupiter-mass planets in the infrared. To achieve the high contrast needed for this, it employs an apodized pupil Lyot coronagraph (APLC) to remove most ... More
Fast computation of Lyot-style coronagraph propagationNov 02 2007We present a new method for numerical propagation through Lyot-style coronagraphs using finite occulting masks. Standard methods for coronagraphic simulations involve Fast Fourier Transforms (FFT) of very large arrays, and computing power is an issue ... More
A generic framework for the development of geospatial processing pipelines on clustersSep 28 2016The amount of remote sensing data available to applications is constantly growing due to the rise of very-high-resolution sensors and short repeat cycle satellites. Consequently, tackling computational complexity in Earth Observation information extraction ... More
Diffusion, localization and dispersion relations on ``small-world'' latticesMar 23 1999The spectral properties of the Laplacian operator on ``small-world'' lattices, that is mixtures of unidimensional chains and random graphs structures are investigated numerically and analytically. A transfer matrix formalism including a self-consistent ... More
Inference with Hamiltonian Sequential Monte Carlo SimulatorsDec 19 2018The paper proposes a new Monte-Carlo simulator combining the advantages of Sequential Monte Carlo simulators and Hamiltonian Monte Carlo simulators. The result is a method that is robust to multimodality and complex shapes to use for inference in presence ... More
Cascade of phase shifts for nonlinear Schrodinger equationsFeb 11 2005We consider a semi-classical nonlinear Schrodinger equation. For initial data causing focusing at one point in the linear case, we study a nonlinearity which is super-critical in terms of asymptotic effects near the caustic. We prove the existence of ... More
Introduction to Phase Transitions in Random Optimization ProblemsApr 19 2007Notes of the lectures delivered in Les Houches during the Summer School on Complex Systems (July 2006).
Une propriete du groupe a 168 elementsMar 24 2003Let an affine space of dimension n over a field k. To each point correponds a section of the linear group G to the affine group. Generally, every section is like this, excpt in the case card(k)=2 and n=3, where G is the group of cardinality 168.
Nonlinear Schrodinger equations with repulsive harmonic potential and applicationsOct 31 2002Mar 14 2003We study the Cauchy problem for Schrodinger equations with repulsive quadratic potential and power-like nonlinearity. The local problem is well-posed in the same space as that used when a confining harmonic potential is involved. For a defocusing nonlinearity, ... More
Differential fields and Geodesic flows II : Geodesic flows of pseudo-Riemannian algebraic varietiesMar 01 2017We define the notion of a smooth pseudo-Riemannian algebraic variety $(X,g)$ over a field $k$ of characteristic $0$, which is an algebraic analogue of the notion of Riemannian manifold and we study, from a model-theoretic perspective, the algebraic differential ... More
Tensorizing maximal correlationsApr 09 2010Dec 30 2010The maximal (or Hilbertian) correlation coefficient between two random variables X and Y, denoted by \{X:Y\}, is the supremum of the |Corr(f(X),g(Y))| for real measurable functions f, g, where "Corr" denotes Pearson's correlation coefficient. It is a ... More
Remarks on nonlinear Schroedinger equations with harmonic potentialNov 24 2001Dec 17 2001Bose-Einstein condensation is usually modeled by nonlinear Schroedinger equations with harmonic potential. We study the Cauchy problem for these equations. We show that the local problem can be treated as in the case with no potential. For the global ... More
Perturbed geodesics on the moduli space of flat connections and Yang-Mills theoryJun 28 2010If we consider the moduli space of flat connections of a non trivial principal SO(3)-bundle over a surface, then we can define a map from the set of perturbed closed geodesics, below a given energy level, into families of perturbed Yang-Mills connections ... More
Optimisation problems and replica symmetry breaking in finite connectivity spin-glassesJul 09 1997Oct 25 1997A formalism capable of handling the first step of hierarchical replica symmetry breaking in finite-connectivity models is introduced. The emerging order parameter is claimed to be a probability distribution over the space of field distributions (or, equivalently ... More
Critical nonlinear Schroedinger equations with and without harmonic potentialDec 21 2001May 15 2002We use a change of variables that turns the critical nonlinear Schroedinger equation into the critical nonlinear Schroedinger equation with isotropic harmonic potential, in any space dimension. This change of variables is isometric on $L^2$, and bijective ... More
Heat flow on the moduli space of flat connections and Yang-Mills theoryAug 02 2010Apr 07 2013It is known that there is a bijection between the perturbed closed geodesics, below a given energy level, on the moduli space of flat connections M and families of perturbed Yang-Mills connections depending on a small parameter. In this paper we study ... More
Some ideas about quantitative convergence of collision models to their mean field limitFeb 04 2009May 06 2009We consider a stochastic $N$-particle model for the spatially homogeneous Boltzmann evolution and prove its convergence to the associated Boltzmann equation when $N\to \infty$. For any time $T>0$ we bound the distance between the empirical measure of ... More
Stable blow-up dynamic for the parabolic-parabolic Patlak-Keller-Segel modelMar 19 2014We consider the parabolic-parabolic two-dimensional Patlak-Keller-Segel problem. We prove the existence of stable blow-up dynamics in finite time in the radial case. We extend in this article the result of [36] for the parabolic-elliptic case.
Future Gravitational Wave Detectors Based on Atom InterferometryNov 29 2016We present the perspective of using atom interferometry for gravitational wave (GW) detection in the mHz to about 10 Hz frequency band. We focus on light-pulse atom interferometers which have been subject to intense developments in the last 25 years. ... More
Stochastic Homogenization of Reflected Diffusion ProcessesDec 20 2007Sep 18 2009We investigate a functional limit theorem (homogenization) for Reflected Stochastic Differential Equations on a half-plane with stationary coefficients when it is necessary to analyze both the effective Brownian motion and the effective local time. We ... More
Stochastic Equivariant Cohomologies and Cyclic CohomologyJul 22 2005We give two stochastic diffeologies on the free loop space which allow us to define stochastic equivariant cohomology theories in the Chen-Souriau sense and to establish a link with cyclic cohomology. With the second one, we can establish a stochastic ... More
Planetary system, star formation, and black hole science with non-redundant masking on space telescopesApr 08 2009Apr 13 2009Non-redundant masking (NRM) is a high contrast, high resolution technique relevant to future space missions concerned with extrasolar planetary system and star formation, as well as general high angular resolution galactic and extragalactic astronomy. ... More
Orbital Motion of HR 8799 b,c, d using Hubble Space Telescope data from 1998: Constraints on Inclination, Eccentricity and StabilityOct 06 2011HR 8799 is currently the only multiple-planet system that has been detected with direct imaging, with four giant planets orbiting at large separations from this young late A star. Orbital motion provides insight into the stability, and possible formation ... More
Low Order Aberrations in Band-Limited Lyot CoronagraphsJul 22 2005We study the way Lyot coronagraphs with unapodized entrance pupils respond to small, low order phase aberrations. This study is applicable to ground-based adaptive optics coronagraphs operating at 90% and higher Strehl ratios, as well as to some space-based ... More
High-contrast imager for complex aperture telescopes (HiCAT): 5. first results with segmented-aperture coronagraph and wavefront controlMar 13 2019Segmented telescopes are a possibility to enable large-aperture space telescopes for the direct imaging and spectroscopy of habitable worlds. However, the complexity of their aperture geometry, due to the central obstruction, support structures and segment ... More
Active Regression by StratificationOct 22 2014We propose a new active learning algorithm for parametric linear regression with random design. We provide finite sample convergence guarantees for general distributions in the misspecified model. This is the first active learner for this setting that ... More
Fast Inference of Interactions in Assemblies of Stochastic Integrate-and-Fire Neurons from Spike RecordingsFeb 25 2011We present two Bayesian procedures to infer the interactions and external currents in an assembly of stochastic integrate-and-fire neurons from the recording of their spiking activity. The first procedure is based on the exact calculation of the most ... More
Theoretical study of collective modes in DNA at ambient temperatureNov 02 1999The instantaneous normal modes corresponding to base pair vibrations (radial modes) and twist angle fluctuations (angular modes) of a DNA molecule model at ambient temperature are theoretically investigated. Due to thermal disorder, normal modes are not ... More
Statistical Mechanics of Torque Induced Denaturation of DNAApr 20 1999Sep 24 1999A unifying theory of the denaturation transition of DNA, driven by temperature T or induced by an external mechanical torque Gamma is presented. Our model couples the hydrogen-bond opening and the untwisting of the helicoidal molecular structure. We show ... More
Scaling limits for symmetric Ito-Levy processes in random mediumDec 19 2008Dec 26 2008We are concerned with scaling limits of the solutions to stochastic differential equations with stationary coefficients driven by Poisson random measures and Brownian motions. We state an annealed convergence theorem, in which the limit exhibits a diffusive ... More
Circuits in random graphs: from local trees to global loopsJul 09 2004We compute the number of circuits and of loops with multiple crossings in random regular graphs. We discuss the importance of this issue for the validity of the cavity approach. On the one side we obtain analytic results for the infinite volume limit ... More
Relaxation and Metastability in the RandomWalkSAT search procedureJan 15 2003Jan 29 2003An analysis of the average properties of a local search resolution procedure for the satisfaction of random Boolean constraints is presented. Depending on the ratio alpha of constraints per variable, resolution takes a time T_res growing linearly (T_res ... More
On the role of quadratic oscillations in nonlinear Schroedinger equations II. The $L^2$-critical caseApr 09 2004Sep 06 2004We consider a nonlinear semi-classical Schroedinger equation for which quadratic oscillations lead to focusing at one point, described by a nonlinear scattering operator. The relevance of the nonlinearity was discussed by R. Carles, C. Fermanian-Kammerer ... More
A Krylov Stability-Corrected Coordinate-Stretching Method to Simulate Wave Propagation in Unbounded DomainsFeb 02 2012Apr 13 2012The Krylov subspace projection approach is a well-established tool for the reduced order modeling of dynamical systems in the time domain. In this paper, we address the main issues obstructing the application of this powerful approach to the time-domain ... More
The Entropy of the K-Satisfiability ProblemMar 02 1996The threshold behaviour of the K-Satisfiability problem is studied in the framework of the statistical mechanics of random diluted systems. We find that at the transition the entropy is finite and hence that the transition itself is due to the abrupt ... More
Robust Model Reduction by $L^1$-norm Minimization and Approximation via Dictionaries: Application to Linear and Nonlinear Hyperbolic ProblemsJun 19 2015We propose a novel model reduction approach for the approximation of non linear hyperbolic equations in the scalar and the system cases. The approach relies on an offline computation of a dictionary of solutions together with an online $L^1$-norm minimization ... More
Reconstructing a Random Potential from its Random WalksApr 19 2007The problem of how many trajectories of a random walker in a potential are needed to reconstruct the values of this potential is studied. We show that this problem can be solved by calculating the probability of survival of an abstract random walker in ... More
Science with Liquid Mirror Telescopes: Season 1996 of NASA Orbital Debris ObservatoryJun 16 1997We present preliminary results of observations made, during the spring of 1996, with the 3-m liquid mirror telescope of the NASA Orbital Debris Observatory. A 20-arcmin-wide strip of sky was observed at latitude of 32deg56 N using 10 narrow-band filters. ... More
Nonlinear Schrodinger equations with Stark potentialFeb 27 2003Apr 28 2003We study the nonlinear Schrodinger equations with a linear potential. A change of variables makes it possible to deduce results concerning finite time blow up and scattering theory from the case with no potential.
Splitting methods for the nonlocal Fowler equationSep 15 2011Aug 09 2012We consider a nonlocal scalar conservation law proposed by Andrew C. Fowler to describe the dynamics of dunes, and we develop a numerical procedure based on splitting methods to approximate its solutions. We begin by proving the convergence of the well-known ... More
Trajectories in phase diagrams, growth processes and computational complexity: how search algorithms solve the 3-Satisfiability problemSep 26 2000Most decision and optimization problems encountered in practice fall into one of two categories with respect to any particular solving method or algorithm: either the problem is solved quickly (easy) or else demands an impractically long computational ... More
Produit de Moyal stochastique sur l'espace de WienerSep 24 2004We propose a stochastic extension of deformation quantization on a Hilbert space. The Moyal product is defined in this context on the space of functionals belonging to all of the Sobolev spaces of the Malliavin calculus.
Stable blow up dynamics for the 1-corotational energy critical harmonic heat flowJun 05 2011We exhibit a stable finite time blow up regime for the 1-corotational energy critical harmonic heat flow from $\Bbb R^2$ into a smooth compact revolution surface of $\Bbb R^3$ which reduces to the semilinear parabolic problem $$\partial_t u -\pa^2_{r} ... More
Energy cascades for NLS on the torusOct 25 2010We consider the nonlinear Schrodinger equation with cubic (focusing or defocusing) nonlinearity on the multidimensional torus. For special small initial data containing only five modes, we exhibit a countable set of time layers in which arbitrarily large ... More
From inherent structures to pure states: some simple remarks and examplesDec 03 1999Feb 16 2000The notions of pure states and inherent structures, i.e. stable configurations against 1-spin flip are discussed. We explain why these different concepts accidentally coincide in mean-field models with infinite connectivity and present an exactly solvable ... More
Learning and generalization theories of large committee--machinesJan 25 1996The study of the distribution of volumes associated to the internal representations of learning examples allows us to derive the critical learning capacity ($\alpha_c=\frac{16}{\pi} \sqrt{\ln K}$) of large committee machines, to verify the stability of ... More
On the stability of critical chemotactic aggregationSep 12 2012We consider the two dimensional parabolic-elliptic Patlak-Keller-Segel model of chemotactic aggregation for radially symmetric initial data. We show the existence of a stable mechanism of singularity formation and obtain a complete description of the ... More
Quantized slow blow up dynamics for the corotational energy critical harmonic heat flowJan 09 2013We consider the energy critical harmonic heat flow from $\Bbb R^2$ into a smooth compact revolution surface of $\Bbb R^3$. For initial data with corotational symmetry, the evolution reduces to the semilinear radially symmetric parabolic problem $$\partial_t ... More
ECN verbose mode: a statistical method for network path congestion estimationOct 23 2009Feb 15 2010This article introduces a simple and effective methodology to determine the level of congestion in a network with an ECN-like marking scheme. The purpose of the ECN bit is to notify TCP sources of an imminent congestion in order to react before losses ... More
Analysis of the computational complexity of solving random satisfiability problems using branch and bound search algorithmsDec 11 2000The computational complexity of solving random 3-Satisfiability (3-SAT) problems is investigated. 3-SAT is a representative example of hard computational tasks; it consists in knowing whether a set of alpha N randomly drawn logical constraints involving ... More
Washing out of the 0-pi transition in Josephson junctionsJul 21 2014We consider a Josephson junction formed by a quantum dot connected to two bulk superconductors in presence of Coulomb interaction and coupling to both an electromagnetic environment and a finite density of electronic quasi-particles. In the limit of large ... More
The expansion of polynomial invariants for $2$-decompositions of generalized graphsAug 23 2016The $2$-decomposition for ribbon graphs was introduced in [Annals of Combinatorics 15 (2011), pp 675-706]. We extend this result to half-edged ribbon graphs and to rank $D$-weakly colored graphs [SIGMA 12 (2016), 030], generalizing therefore the $2$-sums ... More
Tricritical Points in Random Combinatorics: the (2+p)-SAT caseOct 01 1998The (2+p)-Satisfiability (SAT) problem interpolates between different classes of complexity theory and is believed to be of basic interest in understanding the onset of typical case complexity in random combinatorics. In this paper, a tricritical point ... More
A collective phase in resource competition in a highly diverse ecosystemSep 05 2016Organisms shape their own environment, which in turn affects their survival. This feedback becomes especially important for communities containing a large number of species; however, few existing approaches allow studying this regime, except in simulations. ... More
When sound slows down bubblesJan 21 2010Apr 06 2010We present experimental evidence that a bubble moving in a fluid in which a well-chosen acoustic noise is superimposed can be significantly slowed down for moderate acoustic pressures. Through mean velocity measurements, we show that a condition for this ... More
Toward Optimal Stratification for Stratified Monte-Carlo IntegrationMar 12 2013We consider the problem of adaptive stratified sampling for Monte Carlo integration of a noisy function, given a finite budget n of noisy evaluations to the function. We tackle in this paper the problem of adapting to the function at the same time the ... More
Heuristic average-case analysis of the backtrack resolution of random 3-Satisfiability instancesJan 14 2004An analysis of the average-case complexity of solving random 3-Satisfiability (SAT) instances with backtrack algorithms is presented. We first interpret previous rigorous works in a unifying framework based on the statistical physics notions of dynamical ... More
Dictionary Identification - Sparse Matrix-Factorisation via $\ell_1$-MinimisationApr 30 2009Mar 01 2010This article treats the problem of learning a dictionary providing sparse representations for a given signal class, via $\ell_1$-minimisation. The problem can also be seen as factorising a $\ddim \times \nsig$ matrix $Y=(y_1 >... y_\nsig), y_n\in \R^\ddim$ ... More
Focusing of Spherical Nonlinear Pulses in ${\mathbb R}^{1+3}$, III. Sub and Supercritical casesDec 20 2002We study the validity of geometric optics in $L^\infty$ for nonlinear wave equations in three space dimensions whose solutions, pulse like, focus at a point. If the amplitude of the initial data is subcritical, then no nonlinear effect occurs at leading ... More
On a Nonlinear Partial Integro-Differential EquationNov 19 2009Consistently fitting vanilla option surfaces is an important issue when it comes to modelling in finance. Local volatility models introduced by Dupire in 1994 are widely used to price and manage the risks of structured products. However, the inconsistencies ... More
Semiclassical Nonlinear Schrodinger equations with potential and focusing initial dataDec 19 2002Jul 03 2003We study the asymptotic behaviour of solutions to semi-classical nonlinear Schrodinger equations with a potential, for concentrating and oscillating initial data, when the nonlinearity is repulsive and the potential is a polynomial of degree at most two. ... More
Elliptic Yang-Mills Flow TheoryMar 06 2013Dec 05 2013We lay the foundations of a Morse homology on the space of connections on a principal $G$-bundle over a compact manifold $Y$, based on a newly defined gauge-invariant functional $\mathcal J$. While the critical points of $\mathcal J$ correspond to Yang-Mills ... More
Discovery of a low-mass companion inside the debris ring surrounding the F5V star HD206893Dec 01 2016Dec 06 2016Uncovering the ingredients and the architecture of planetary systems is a very active field of research that has fuelled many new theories on giant planet formation, migration, composition, and interaction with the circumstellar environment. We aim at ... More
Apodized Pupil Lyot Coronagraphs for Arbitrary Apertures. IV. Reduced Inner Working Angle and Increased Robustness to Low-Order AberrationsDec 08 2014The Apodized Pupil Lyot Coronagraph (APLC) is a diffraction suppression system installed in the recently deployed instruments Palomar/P1640, Gemini/GPI, and VLT/SPHERE to allow direct imaging and spectroscopy of circumstellar environments. Using a prolate ... More
Introduction to stellar coronagraphyMar 26 2007Oct 06 2008This paper gives a simple and original presentation of various coronagraphs inherited from the Lyot coronagraph. We first present the Lyot and Roddier phase mask coronagraphs and study their properties as a function of the focal mask size. We show that ... More
Electrical-modelling, design and simulation of cumulative radiation effects in semiconductor pixels detectors: prospects and limitsOct 28 2014Nov 19 2014Silicon detectors have gained in popularity since silicon became a widely used micro/nanoelectronic semiconductor material. Silicon detectors are used in particle physics as well as imaging for pixel based detecting systems. Over the past twenty years ... More
Obstructed Telescopes vs Unobstructed Telescopes for Wide Field Survey - A Quantitative AnalysisMar 12 2014Telescopes with unobstructed pupil are known to deliver clean point spread function (PSF) to their focal plane, in contrast to traditional telescopes with obstructed pupil. Recent progress in the manufacturing aspheric surfaces and mounting accuracy favors ... More
The dynamics of proving uncolourability of large random graphs I. Symmetric Colouring HeuristicApr 28 2003We study the dynamics of a backtracking procedure capable of proving uncolourability of graphs, and calculate its average running time T for sparse random graphs, as a function of the average degree c and the number of vertices N. The analysis is carried ... More
Assessment of algorithms for computing moist available potential energyDec 06 2017Atmospheric moist available potential energy (MAPE) has been traditionally defined as the potential energy of a moist atmosphere relative to that of the adiabatically sorted reference state defining a global potential energy minimum. Finding such a reference ... More
Magnetic Field dragging in accretion discsDec 22 2011Accretion discs are composed of ionized gas in motion around a central object. Sometimes, the disc is the source of powerful bipolar jets along its rotation axis. Theoretical models invoke the existence of a bipolar magnetic field crossing the disc and ... More
Characterizing the Atmospheres of the HR8799 Planets with HST/WFC3Aug 10 2015We present results from a Hubble Space Telescope (HST) program characterizing the atmospheres of the outer two planets, in the HR8799 system. The images were taken over 15 orbits in three near-infrared medium-band filters - F098M, F127M and F139M - using ... More
Temporal Evolution of Coronagraphic Dynamic Range, and Constraints on Companions to VegaSep 12 2006The major obstacle to the direct detection of companions to nearby stars is the overwhelming brightness of the host star. Current instruments employing the combination of adaptive optics (AO) and coronagraphy can typically detect objects within 2'' of ... More
WFIRST-AFTA Coronagraphic Operations: Lessons Learned from the Hubble Space Telescope and the James Webb Space TelescopeNov 19 2015The coronagraphic instrument currently proposed for the WFIRST-AFTA mission will be the first example of a space-based coronagraph optimized for extremely high contrasts that are required for the direct imaging of exoplanets reflecting the light of their ... More
Speckle Suppression Through Dual Imaging Polarimetry, and a Ground-Based Image of the HR 4796A Circumstellar DiskJun 16 2009Jun 25 2009We demonstrate the versatility of a dual imaging polarimeter working in tandem with a Lyot coronagraph and Adaptive Optics to suppress the highly static speckle noise pattern--the greatest hindrance to ground-based direct imaging of planets and disks ... More
The Gemini Planet Imager: First LightMar 28 2014The Gemini Planet Imager (GPI) is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph ... More
Comparison of optical observational capabilities for the coming decades: ground versus spaceSep 24 2009Ground-based adaptive optics (AO) in the infrared has made exceptional advances in approaching space-like image quality at higher collecting area. Optical-wavelength applications are now also growing in scope. We therefore provide here a comparison of ... More
A variational description of the ground state structure in random satisfiability problemsJul 22 1999Nov 15 1999A variational approach to finite connectivity spin-glass-like models is developed and applied to describe the structure of optimal solutions in random satisfiability problems. Our variational scheme accurately reproduces the known replica symmetric results ... More
Balancing building and maintenance costs in growing transport networksSep 21 2016Sep 29 2016The costs associated to the length of links impose unavoidable constraints to the growth of natural and artificial transport networks. When future network developments can not be predicted, building and maintenance costs require competing minimization ... More
Stochastic Ratchet Mechanisms for Replacement of Proteins Bound to DNAMay 26 2014Experiments indicate that unbinding rates of proteins from DNA can depend on the concentration of proteins in nearby solution. Here we present a theory of multi-step replacement of DNA-bound proteins by solution-phase proteins. For four different kinetic ... More
Separation of Reliability and Secrecy in Rate-Limited Secret-Key GenerationOct 16 2012May 16 2014For a discrete or a continuous source model, we study the problem of secret-key generation with one round of rate-limited public communication between two legitimate users. Although we do not provide new bounds on the wiretap secret-key (WSK) capacity ... More
GNU Radio Implementation of MALIN: "Multi-Armed bandits Learning for Internet-of-things Networks"Feb 05 2019We implement an IoT network the following way: one gateway, one or several intelligent (i.e., learning) objects, embedding the proposed solution, and a traffic generator that emulates radio interferences from many other objects. Intelligent objects communicate ... More
Under-determined reverberant audio source separation using a full-rank spatial covariance modelDec 01 2009Dec 14 2009This article addresses the modeling of reverberant recording environments in the context of under-determined convolutive blind source separation. We model the contribution of each source to all mixture channels in the time-frequency domain as a zero-mean ... More
Anomalous Low-Field Classical Magnetoresistance in Two DimensionsDec 09 2002The magnetoresistance of classical two-dimensional electrons scattered by randomly distributed impurities is investigated by numerical simulation. At low magnetic fields, we find for the first time a negative magnetoresistance proportional to |B|. This ... More
Higher order Schrodinger and Hartree-Fock equationsMay 21 2013Nov 19 2015The domain of validity of the higher-order Schrodinger equations is analyzed for harmonic-oscillator and Coulomb potentials as typical examples. Then the Cauchy theory for higher-order Hartree-Fock equations with bounded and Coulomb potentials is developed. ... More
On the Connection between Residual Distribution Schemes and Flux ReconstructionJul 03 2018In this short paper, we are considering the connection between the \emph{Residual Distribution Schemes} (RD) and the \emph{Flux Reconstruction} (FR) approach. We demonstrate that flux reconstruction can be recast into the RD framework and vice versa. ... More
Iowa Particle Flow AlgorithmFeb 29 2012The particle detectors at the future linear colliders, like ILD and SiD, use Particle Flow Algorithms (PFA)s to reach higher jet energy resolutions than the classical pure calorimetry. During the past few years, the University of Iowa group developed ... More
Effect of angular opening on the dynamics of relativistic hydro jetsNov 07 2012Context. Relativistic jets emerging from AGN cores transfer energy from the core to their surrounding ISM/IGM. Because jets are observed to have finite opening angles, one needs to quantify the role of conical versus cylindrical jet propagation in this ... More
Recent Belle results from Y(5S) sampleNov 01 2011The large data sample recorded with the Belle detector at the Y(5S) energy provides a unique opportunity to study the poorly-known $\bs$ meson. Two analyses, performed with a data sample representing an integrated luminosity of 121 /fb, are presented: ... More
Bs0 Decays at BelleSep 14 2010Jan 05 2011The large data sample recorded with the Belle detector at the Y(5S) energy provides a unique opportunity to study the poorly-known Bs0 meson. Several analyses, made with a data sample representing an integrated luminosity of 23.6 /fb, are presented. We ... More
Non-convex regularization in remote sensingJun 23 2016In this paper, we study the effect of different regularizers and their implications in high dimensional image classification and sparse linear unmixing. Although kernelization or sparse methods are globally accepted solutions for processing data in high ... More
Neural Text Generation from Structured Data with Application to the Biography DomainMar 24 2016Sep 23 2016This paper introduces a neural model for concept-to-text generation that scales to large, rich domains. We experiment with a new dataset of biographies from Wikipedia that is an order of magnitude larger than existing resources with over 700k samples. ... More
Disjunctive Answer Set Solvers via TemplatesOct 06 2015Answer set programming is a declarative programming paradigm oriented towards difficult combinatorial search problems. A fundamental task in answer set programming is to compute stable models, i.e., solutions of logic programs. Answer set solvers are ... More
A spectral unaveraged algorithm for free electron laser simulationsMay 08 2014Oct 06 2014We propose and discuss a numerical method to model electromagnetic emission from the oscillating relativistic charged particles and its coherent amplification. The developed technique is well suited for free electron laser simulations, but it may also ... More
Theory of spike timing based neural classifiersOct 26 2010We study the computational capacity of a model neuron, the Tempotron, which classifies sequences of spikes by linear-threshold operations. We use statistical mechanics and extreme value theory to derive the capacity of the system in random classification ... More
DC Proximal Newton for Non-Convex Optimization ProblemsJul 02 2015We introduce a novel algorithm for solving learning problems where both the loss function and the regularizer are non-convex but belong to the class of difference of convex (DC) functions. Our contribution is a new general purpose proximal Newton algorithm ... More