Results for "Edward R Dougherty"

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Moments and Root-Mean-Square Error of the Bayesian MMSE Estimator of Classification Error in the Gaussian ModelOct 05 2013Nov 12 2013The most important aspect of any classifier is its error rate, because this quantifies its predictive capacity. Thus, the accuracy of error estimation is critical. Error estimation is problematic in small-sample classifier design because the error must ... More
Optimal Bayesian Transfer LearningJan 02 2018May 25 2018Transfer learning has recently attracted significant research attention, as it simultaneously learns from different source domains, which have plenty of labeled data, and transfers the relevant knowledge to the target domain with limited labeled data ... More
Experimental Design via Generalized Mean Objective Cost of UncertaintyMay 03 2018The mean objective cost of uncertainty (MOCU) quantifies the performance cost of using an operator that is optimal across an uncertainty class of systems as opposed to using an operator that is optimal for a particular system. MOCU-based experimental ... More
Optimal Clustering under UncertaintyJun 02 2018Classical clustering algorithms typically either lack an underlying probability framework to make them predictive or focus on parameter estimation rather than defining and minimizing a notion of error. Recent work addresses these issues by developing ... More
Sequential Experimental Design for Optimal Structural Intervention in Gene Regulatory Networks Based on the Mean Objective Cost of UncertaintyMay 30 2018Scientists are attempting to use models of ever increasing complexity, especially in medicine, where gene-based diseases such as cancer require better modeling of cell regulation. Complex models suffer from uncertainty and experiments are needed to reduce ... More
Scalable optimal Bayesian classification of single-cell trajectories under regulatory model uncertaintyFeb 08 2019Single-cell gene expression measurements offer opportunities in deriving mechanistic understanding of complex diseases, including cancer. However, due to the complex regulatory machinery of the cell, gene regulatory network (GRN) model inference based ... More
Autonomous Efficient Experiment Design for Materials Discovery with Bayesian Model AveragingMar 14 2018Oct 30 2018The accelerated exploration of the materials space in order to identify configurations with optimal properties is an ongoing challenge. Current paradigms are typically centered around the idea of performing this exploration through high-throughput experimentation/computation. ... More
Measuring the Size of the Vela Pulsar's Radio Emission RegionFeb 04 2000We describe measurements of the size of the Vela pulsar via scintillation, using both fits to the distribution of intensity and measurements of the modulation index. We briefly discuss systematic effects other than source size that can affect the distribution, ... More
Translating the Cantor set by a randomMay 22 2012We determine the constructive dimension of points in random translates of the Cantor set. The Cantor set "cancels randomness" in the sense that some of its members, when added to Martin-Lof random reals, identify a point with lower constructive dimension ... More
The VSOP 5 GHz AGN Survey II. Data Calibration and ImagingJul 01 2004The VSOP mission is a Japanese-led project to study radio sources with sub-milliarcsecond angular resolution using an orbiting 8-m telescope, HALCA and global arrays of Earth-based telescopes. Approximately 25% of the observing time has been devoted to ... More
Noise in the Cross-Power Spectrum of the Vela PulsarJul 31 2012Sep 21 2012We compare the noise in interferometric measurements of the Vela pulsar from ground- and space-based antennas with theoretical predictions. The noise depends on both the flux density and the interferometric phase of the source. Because the Vela pulsar ... More
Size of the Vela Pulsar's Emission Region at 18 cm WavelengthJul 31 2012Sep 21 2012We present measurements of the linear diameter of the emission region of the Vela pulsar at observing wavelength lambda=18 cm. We infer the diameter as a function of pulse phase from the distribution of visibility on the Mopra-Tidbinbilla baseline. As ... More
Data management to support reproducible researchFeb 21 2015We describe the current state and future plans for a set of tools for scientific data management (SDM) designed to support scientific transparency and reproducible research. SDM has been in active use at our MRI Center for more than two years. We designed ... More
Iterated Monodromy Groups of Intermediate GrowthAug 05 2012Aug 29 2013We give two new examples of groups of intermediate growth, by a method that was first used by Bux and P\'erez. Our examples are the groups generated by the automata with the kneading sequences 11(0) and 0(011). By results of Nekrashevych, both of these ... More
Spatial First-passage Statistics of Al/Si(111)-(root3 x root3) Step FluctuationsOct 02 2008Spatial step edge fluctuations on a multi-component surface of Al/Si(111)-(root3 x root3) were measured via scanning tunneling microscopy over a temperature range of 720K-1070K, for step lengths of L = 65-160 nm. Even though the time scale of fluctuations ... More
The Large Adaptive Reflector conceptOct 18 2005Cost effective, new antenna technology is required to build the large collecting area being planned for the next generation of radio telescopes. The Large Adaptive Reflector (LAR) is a novel concept being developed in Canada to meet this challenge. A ... More
Action Variable Quantization, Energy Quantization, and Time ParametrizationAug 02 2015Mar 17 2016Additional information in the Hamilton-Jacobi representation of quantum mechanics, not available in the Schr\"odinger representation, renders microstates of $\psi$. This additional information is incorporated into the quantum reduced action, $W$. Jacobi's ... More
Dynamics of transcription-translation networksMay 26 2016A theory for qualitative models of gene regulatory networks has been developed over several decades, generally considering transcription factors to regulate directly the expression of other transcription factors, without any intermediate variables. Here ... More
Nature of the MHD and kinetic scale turbulence in the magnetosheath of Saturn: Cassini observationsNov 24 2016Low frequency turbulence in Saturn's magnetosheath is investigated using in-situ measurements of the Cassini spacecraft. Focus is put on the magnetic energy spectra computed in the frequency range $\sim[10^{-4}, 1]$Hz. A set of 42 time intervals in the ... More
Comments on Bouda and Djama's "Quantum Newton's law"Jun 18 2002Discussion of the differences between the trajectory representation of Floyd and that of Bouda and Djama [Phys. Lett. A 285 (2001) 27, quant-ph/0103071] renders insight: while Floyd's trajectories are related to group velocities, Bouda and Djama's are ... More
Undesired parking spaces and contractible pieces of the noncrossing partition linkJul 20 2017There are two natural simplicial complexes associated to the noncrossing partition lattice: the order complex of the full lattice and the order complex of the lattice with its bounding elements removed. The latter is a complex that we call the noncrossing ... More
Radio emission models of Colliding-Wind Binary SystemsJul 09 2003We present calculations of the spatial and spectral distribution of the radio emission from a wide WR+OB colliding-wind binary system based on high-resolution hydrodynamical simulations and solutions to the radiative transfer equation. We account for ... More
A tidal disruption-like X-ray flare from the quiescent galaxy SDSS J120136.02+300305.5Feb 27 2012SDSS J120136.02+300305.5 was detected in an XMM-Newton slew from June 2010 with a flux 56 times higher than an upper limit from ROSAT, corresponding to Lx~3x10^44 ergs/s. It has the optical spectrum of a quiescent galaxy (z=0.146). Overall the X-ray flux ... More
The Evolution of Distorted Rotating Black Holes I: Methods and TestsDec 22 1994We have developed a new numerical code to study the evolution of distorted, rotating black holes. We discuss the numerical methods and gauge conditions we developed to evolve such spacetimes. The code has been put through a series of tests, and we report ... More
High resolution radio emission from RCW 49/Westerlund 2Jul 24 2013Aug 19 2013RCW49 and its ionizing cluster form an extensive, complex region, widely studied at IR and optical wavelengths. Molonglo 843 MHz and ATCA data at 1.4 and 2.4 GHz showed two shells. Recent high-resolution IR imaging revealed a complex dust structure and ... More
Expanded Very Large ArrayNov 02 2010The Very Large Array is undergoing a major upgrade that will attain an order of magnitude improvement in continuum sensitivity across 1 to 50 GHz with instantaneous bandwidths up to 8 GHz in both polarizations. The new WIDAR correlator provides a highly ... More
Superconformal Field Theory on Threebranes at a Calabi-Yau SingularityJul 10 1998Jul 22 1998Just as parallel threebranes on a smooth manifold are related to string theory on $AdS_5\times {\bf S}^5$, parallel threebranes near a conical singularity are related to string theory on $AdS_5\times X_5$, for a suitable $X_5$. For the example of the ... More
Proton Decay in Intersecting D-brane ModelsApr 08 2003Jun 04 2003We analyze proton decay via dimension six operators in certain GUT-like models derived from Type IIA orientifolds with $D6$-branes. The amplitude is parametrically enhanced by a factor of $\alpha_{GUT}^{-1/3}$ relative to the coresponding result in four-dimensional ... More
AdS/CFT Correspondence and Symmetry BreakingMay 15 1999Jun 03 1999We study, using the dual AdS description, the vacua of field theories where some of the gauge symmetry is broken by expectation values of scalar fields. In such vacua, operators built out of the scalar fields acquire expectation values, and we show how ... More
The Evolution of Distorted Rotating Black Holes III: Initial DataJan 09 1996In this paper we study a new family of black hole initial data sets corresponding to distorted ``Kerr'' black holes with moderate rotation parameters, and distorted Schwarzschild black holes with even- and odd-parity radiation. These data sets build on ... More
The Evolution of Distorted Rotating Black Holes II: Dynamics and AnalysisDec 22 1994We have developed a numerical code to study the evolution of distorted, rotating black holes. This code is used to evolve a new family of black hole initial data sets corresponding to distorted ``Kerr'' holes with a wide range of rotation parameters, ... More
Defining ChaosJan 30 2015Apr 28 2015In this paper we propose, discuss and illustrate a computationally feasible definition of chaos which can be applied very generally to situations that are commonly encountered, including attractors, repellers and non-periodically forced systems. This ... More
How many Turing degrees are there?Jan 28 2000A Borel equivalence relation on a Polish space is said to be countable if all of its equivalence classes are countable. Standard examples of countable Borel equivalence relations (on the space of subsets of the integers) that occur in recursion theory ... More
Discovery of extended radio emission in the young cluster Wd1Jul 29 1998We present 10 micron, ISO-SWS and Australia Telescope Compact Array observations of the region in the cluster Wd1 in Ara centred on the B[e] star Ara C. An ISO-SWS spectrum reveals emission from highly ionised species in the vicinity of the star, suggesting ... More
Orbitally modulated dust formation by the WC7+O5 colliding-wind binary WR140Feb 26 2009We present high-resolution infrared (2--18 micron) images of the archetypal periodic dust-making Wolf-Rayet binary system WR140 (HD 193793) taken between 2001 and 2005, and multi-colour (J -- [19.5]) photometry observed between 1989 and 2001. The images ... More
The Three-mm Ultimate Mopra Milky Way Survey. I. Survey Overview, Initial Data Releases, and First ResultsJul 17 2015We describe a new mm-wave molecular-line mapping survey of the southern Galactic Plane and its first data releases. The Three-mm Ultimate Mopra Milky Way Survey (ThrUMMS) maps a 60{\deg}x2{\deg} sector of our Galaxy's fourth quadrant, using a combination ... More
Calculation of Asymptotic and RMS Kicks Due To Higher Order Modes in the 3.9GHz CavitySep 10 2008FLASH plans to use a "third harmonic" (3.9GHz) superconducting cavity to compensate nonlinear distortions of the longitudinal phase space due to the sinusoidal curvature of the the cavity voltage of the TESLA 1.3GHz cavities. Higher order modes (HOMs) ... More
Evidence for Heterotic/Heterotic DualityJan 09 1996We re-examine the question of heterotic - heterotic string duality in six dimensions and argue that the $E_8\times E_8$ heterotic string, compactified on $K3$ with equal instanton numbers in the two $E_8$'s, has a self-duality that inverts the coupling, ... More
Formation of Multifractal Population Patterns from Reproductive Growth and Local ResettlementFeb 04 2005Jul 25 2005We consider the general character of the spatial distribution of a population that grows through reproduction and subsequent local resettlement of new population members. We present several simple one and two-dimensional point placement models to illustrate ... More
Close companions to Brightest Cluster Galaxies: Support for minor mergers and downsizingJun 07 2012We identify close companions of Brightest Cluster Galaxies (BCGs) for the purpose of quantifying the rate at which these galaxies grow via mergers. By exploiting deep photometric data from the CFHTLS, we probe the number of companions per BCG (Nc) with ... More
Drifting sub-pulses in two newly discovered pulsarsSep 12 2001We have detected the rare phenomenon of stable, drifting sub-pulse behaviour in two pulsars discovered in the recent Swinburne intermediate latitude pulsar survey. The pulsars; PSR J1231-47 and PSR J1919+0134, have approximate periods (P) of 1.873 and ... More
Antimicrobial resistance and use, and rates of hospitalization associated with bacterial infections, including sepsisMar 19 2018While the mechanisms and quantitative details are complex, few analysts would doubt that antibiotic use increases the prevalence of drug-resistant bacterial pathogens among all bacteria causing disease in a population. The causal connection between antibiotic ... More
Ballooning Instability in Polar Caps of Accreting Neutron StarsJan 10 2001We assess the stability of Kruskal-Schwarzschild (magnetic Rayleigh-Taylor) type modes for accreted matter on the surface of a neutron star confined by a strong (>= 1.E12 G) magnetic field. Employing the energy principle to analyze the stability of short-wavelength ... More
Orbital stability of periodic waves in the class of reduced Ostrovsky equationsMar 09 2016Periodic travelling waves are considered in the class of reduced Ostrovsky equations that describe low-frequency internal waves in the presence of rotation. The reduced Ostrovsky equations with either quadratic or cubic nonlinearities can be transformed ... More
Scaling Properties of Paths on GraphsJun 12 2013Let $G$ be a directed graph on finitely many vertices and edges, and assign a positive weight to each edge on $G$. Fix vertices $u$ and $v$ and consider the set of paths that start at $u$ and end at $v$, self-intersecting in any number of places along ... More
Light-cone observations and cosmological models: implications for inhomogeneous models mimicking dark energyNov 19 2009Cosmological observables are used to construct cosmological models. Since cosmological observations are limited to the light cone, a fixed number of observables (even measured to arbitrary accuracy) may not uniquely determine a cosmological model without ... More
Flux Compactifications of String Theory on Twisted ToriMar 14 2005Global aspects of Scherk-Schwarz dimensional reduction are discussed and it is shown that it can usually be viewed as arising from a compactification on the compact space obtained by identifying a (possibly non-compact) group manifold G under a discrete ... More
The "fundamental theorem" for the algebraic K-theory of spaces. III. the nil-termMay 07 2007May 08 2007In this paper we identify the ``nil-terms'' for Waldhausen's algebraic K-theory of spaces functor as the reduced K-theory of a category of equivariant spaces equipped with a homotopically nilpotent endomorphism.
A Gravity Dual of the Chiral AnomalyFeb 08 2002Jun 27 2002We study effects associated with the chiral anomaly for a cascading $SU(N+M)\times SU(N)$ gauge theory using gauge/gravity duality. In the gravity dual the anomaly is a classical feature of the supergravity solution, and the breaking of the U(1) R-symmetry ... More
Thermal Processing of Silicate Dust in the Solar Nebula: Clues from Primitive Chondrite MatricesJan 05 2005The most abundant matrix minerals in chondritic meteorites, hydrated phyllosilicates and ferrous olivine crystals, formed predominantly in asteroids during fluid-assisted metamorphism. We infer that they formed from minerals present in three less altered ... More
Ranks and Kernels of Codes from Generalized Hadamard MatricesJun 30 2015The ranks and kernels of generalized Hadamard matrices are studied. It is proven that any generalized Hadamard matrix $H(q,\lambda)$ over $F_q$, $q>3$, or $q=3$ and $\gcd(3,\lambda)\not =1$, generates a self-orthogonal code. This result puts a natural ... More
Boundary BraidsNov 14 2018The n-strand braid group can be defined as the fundamental group of the configuration space of n unlabeled points in a closed disk based at a configuration where all n points lie in the boundary of the disk. Using this definition, the subset of braids ... More
Properties of Saturn Kilometric Radiation measured within its source regionJan 20 2011On 17 October 2008, the Cassini spacecraft crossed the southern sources of Saturn kilometric radiation (SKR), while flying along high-latitude nightside magnetic field lines. In situ measurements allowed us to characterize for the first time the source ... More
A Neutron Star with a Massive Progenitor in Westerlund 1Sep 14 2005Jan 26 2006We report the discovery of an X-ray pulsar in the young, massive Galactic star cluster Westerlund 1. We detected a coherent signal from the brightest X-ray source in the cluster, CXO J164710.2-455216, during two Chandra observations on 2005 May 22 and ... More
The automorphism group of the doubly-even [72,36,16] code can only be of order 1, 3 or 5Mar 20 2013Mar 25 2013We prove that a putative $[72,36,16]$ code is not the image of linear code over $\ZZ_4$, $\FF_2 + u \FF_2$ or $\FF_2+v\FF_2$, thus proving that the extremal doubly even $[72,36,16]$-binary code cannot have an automorphism group containing a fixed point-free ... More
Granular Matter and the Marginal Rigidity StateMay 17 2001Model experiments are reported on the build-up of granular piles in two dimensions. These show that as the initial density of falling grains is increased, the resulting pile has decreasing final density and its coordination number approaches the low value ... More
The complex circumstellar environment of HD142527Jan 29 2011The recent findings of gas giant planets around young A-type stars suggest that disks surrounding Herbig Ae/Be stars will develop planetary systems. An interesting case is HD142527, for which previous observations revealed a complex circumstellar environment ... More
On homeomorphic product measures on the Cantor setNov 15 2004Nov 10 2005Let mu(r) be the Bernoulli measure on the Cantor space given as the infinite product of two-point measures with weights r and 1-r. It is a long-standing open problem to characterize those r and s such that mu(r) and mu(s) are topologically equivalent ... More
Chiral Rings and Anomalies in Supersymmetric Gauge TheoryNov 18 2002Dec 17 2002Motivated by recent work of Dijkgraaf and Vafa, we study anomalies and the chiral ring structure in a supersymmetric U(N) gauge theory with an adjoint chiral superfield and an arbitrary superpotential. A certain generalization of the Konishi anomaly leads ... More
Kinematic entanglement degradation of fermionic cavity modesOct 31 2011Jan 23 2012We analyse the entanglement and the non-locality of a (1+1)-dimensional massless Dirac field confined to a cavity on a worldtube that consists of inertial and uniformly accelerated segments, for small accelerations but arbitrarily long travel times. The ... More
Time evolution techniques for detectors in relativistic quantum informationDec 10 2012Apr 06 2013The techniques employed to solve the interaction of a detector and a quantum field typically require perturbation methods. We introduce mathematical techniques to solve the time evolution of an arbitrary number of detectors interacting with a quantum ... More
On vertex, edge, and vertex-edge random graphsDec 08 2008Oct 13 2010We consider three classes of random graphs: edge random graphs, vertex random graphs, and vertex-edge random graphs. Edge random graphs are Erdos-Renyi random graphs, vertex random graphs are generalizations of geometric random graphs, and vertex-edge ... More
Solving the Pricing Problem in a Branch-and-Price Algorithm for Graph Coloring using Zero-Suppressed Binary Decision DiagramsJan 22 2014Jul 08 2015Branch-and-price algorithms combine a branch-and-bound search with an exponentially-sized LP formulation that must be solved via column generation. Unfortunately, the standard branching rules used in branch-and-bound for integer programming interfere ... More
Nonlinear Waves in an Experimentally Motivated Ring-shaped Bose-Einstein Condensate SetupJan 13 2019We systematically construct stationary soliton states in a one-component, two-dimensional, repulsive, Gross-Pitaevskii equation with a ring-shaped target-like trap similar to the potential used to confine a Bose-Einstein condensate in a recent experiment ... More
Electron acceleration to relativistic energies at a strong quasi-parallel shock waveJan 08 2013Electrons can be accelerated to ultrarelativistic energies at strong (high-Mach number) collisionless shock waves that form when stellar debris rapidly expands after a supernova. Collisionless shock waves also form in the flow of particles from the Sun ... More
The Orbit and Distance of WR140 - Proceedings of "Stellar Winds in Interaction" 2010Jan 05 2011A campaign of 35 epochs of milli-arcsec resolution VLBA observations of the archetype collidingwind WR+O star binary system WR140 show the wind-collision region (WCR) as a bow-shaped arc of emission that rotates as the highly eccentric orbit progresses. ... More
Long Time Algebraic Relaxation in Chaotic BilliardsOct 28 2002The long time algebraic relaxation process in spatially periodic billiards with infinite horizon is shown to display a self-similar time asymptotic form. This form is identical for a class of such billiards, but can be different in an important special ... More
Comment on "Long Time Evolution of Phase Oscillator Systems" [Chaos 19,023117 (2009), arXiv:0902.2773]May 18 2010Jun 25 2010A previous paper (arXiv:0902.2773, henceforth referred to as I) considered a general class of problems involving the evolution of large systems of globally coupled phase oscillators. It was shown there that, in an appropriate sense, the solutions to these ... More
Thermal diffusion of supersonic solitons in an anharmonic chain of atomsFeb 04 2002Nov 16 2002We study the non-equilibrium diffusion dynamics of supersonic lattice solitons in a classical chain of atoms with nearest-neighbor interactions coupled to a heat bath. As a specific example we choose an interaction with cubic anharmonicity. The coupling ... More
Desynchronization waves and localized instabilities in oscillator arraysApr 07 2004We consider a ring of identical or near identical coupled periodic oscillators in which the connections have randomly heterogeneous strength. We use the master stability function method to determine the possible patterns at the desynchronization transition ... More
Strongly Enhanced Stimulated Brillouin Backscattering in an Electron-Positron PlasmaDec 02 2015Jan 07 2016Stimulated Brillouin backscattering of light is shown to be drastically enhanced in electron-positron plasmas, in contrast to the suppression of stimulated Raman scattering. A generalized theory of three-wave coupling between electromagnetic and plasma ... More
Convectively driven shear and decreased heat fluxAug 20 2014We report on direct numerical simulations of two-dimensional, horizontally periodic Rayleigh-B\'enard convection, focusing on its ability to drive large-scale horizontal flow that is vertically sheared. For the Prandtl numbers ($Pr$) between 1 and 10 ... More
The distance and neutral environment of the massive stellar cluster Westerlund 1Apr 23 2007The goal of this study is to determine a distance to Westerlund 1 independent of the characteristics of the stellar population and to study its neutral environment, using observations of atomic hydrogen. The HI observations are taken from the Southern ... More
High resolution cathodoluminescence hyperspectral imaging of surface features in InGaN/GaN multiple quantum well structuresFeb 09 2011Jul 18 2011InGaN/GaN multiple quantum wells (MQWs) have been studied by using cathodoluminescence hyperspectral imaging with high spatial resolution. Variations in peak emission energies and intensities across trench-like features and V-pits on the surface of the ... More
Approximating the largest eigenvalue of network adjacency matricesMay 31 2007The largest eigenvalue of the adjacency matrix of a network plays an important role in several network processes (e.g., synchronization of oscillators, percolation on directed networks, linear stability of equilibria of network coupled systems, etc.). ... More
Spatial patterns of desynchronization bursts in networksJan 07 2004We adapt a previous model and analysis method (the {\it master stability function}), extensively used for studying the stability of the synchronous state of networks of identical chaotic oscillators, to the case of oscillators that are similar but not ... More
Scale dependence of branching in arterial and bronchial treesApr 29 2005Jul 26 2006Although models of branching in arterial and bronchial trees often predict a dependence of bifurcation parameters on the scale of the bifurcating vessels, direct verifications of this dependence with data are uncommon. We compare measurements of bifurcation ... More
Using Learned Predictions as Feedback to Improve Control and Communication with an Artificial Limb: Preliminary FindingsAug 08 2014Many people suffer from the loss of a limb. Learning to get by without an arm or hand can be very challenging, and existing prostheses do not yet fulfil the needs of individuals with amputations. One promising solution is to provide greater communication ... More
Molecular origin of constant m-values, denatured state collapse, and residue-dependent transition midpoints in globular proteinsApr 16 2009Experiments show that for many two state folders the free energy of the native state DG_ND([C]) changes linearly as the denaturant concentration [C] is varied. The slope, m = d DG_ND([C])/d[C], is nearly constant. The m-value is associated with the difference ... More
Near-Infrared Classification Spectroscopy: J-Band Spectra of Fundamental MK StandardsJan 31 2000We present a catalog of J-band spectra for 88 fundamental MK standard stars observed at a resolving power of R ~ 3000. This contribution serves as a companion atlas to the K-band spectra published by Wallace and Hinkle (1997) and the H-band atlas of Meyer ... More
Fermionic mode entanglement in quantum informationNov 30 2012Feb 25 2013We analyze fermionic modes as fundamental entities for quantum information processing. To this end we construct a density operator formalism on the underlying Fock space and demonstrate how it can be naturally and unambiguously equipped with a notion ... More
Optimal multi-dimensional stochastic harvesting with density-dependent pricesJun 30 2014Jun 26 2015We prove a verification theorem for a class of singular control problems which model optimal harvesting with density-dependent prices or optimal dividend policy with capital-dependent utilities. The result is applied to solve explicitly some examples ... More
Ensemble regional data assimilation using joint statesAug 04 2011We propose a data assimilation scheme that produces the analyses for a global and an embedded limited area model simultaneously, considering forecast information from both models. The purpose of the proposed approach is twofold. First, we expect that ... More
Characterization of Saturn's bow shock: Magnetic field observations of quasi-perpendicular shocksMay 16 2016Collisionless shocks vary drastically from terrestrial to astrophysical regimes resulting in radically different characteristics. This poses two complexities. Firstly, separating the influences of these parameters on physical mechanisms such as energy ... More
The magnetic structure of Saturn's magnetosheathFeb 19 2015A planet's magnetosheath extends from downstream of its bow shock up to the magnetopause where the solar wind flow is deflected around the magnetosphere and the solar wind embedded magnetic field lines are draped. This makes the region an important site ... More
False discovery rate analysis of brain diffusion direction mapsMar 26 2008Diffusion tensor imaging (DTI) is a novel modality of magnetic resonance imaging that allows noninvasive mapping of the brain's white matter. A particular map derived from DTI measurements is a map of water principal diffusion directions, which are proxies ... More
Modelling the radio emission from Cyg OB2 #5: a quadruple system?Nov 30 2009Fifty archival radio observations of the supergiant binary Cyg OB2 #5 using the Very Large Array over 20 years are re-examined to determine the location and character of the previously detected variable radio emission. The radio emission from the system ... More
Constructions of Self-Dual and Formally Self-Dual Codes from Group RingsApr 26 2016We give constructions of self-dual and formally self-dual codes from group rings where the ring is a finite commutative Frobenius ring. We improve the existing construction given in \cite{Hurley1} by showing that one of the conditions given in the theorem ... More
The Flat Beam Experiment at the FNAL PhotoinjectorAug 12 2000A technique for production of an electron beam with a high transverse emittance ratio. a "flat" beam, has been proposed by Brinkmann, Derbenev, and Floettmann.[1] The cathode of an RF-laser gun is immersed in a solenoidal magnetic field; as a result the ... More
Space-VLBI observations of OH maser OH34.26+0.15: low interstellar scatteringJul 26 2000We report on the first space-VLBI observations of the OH34.26+0.15 maser in two main line OH transitions at 1665 and 1667 MHz. The observations involved the space radiotelescope on board the Japanese satellite HALCA and an array of ground radio telescopes. ... More
An empirical approach to interpreting card-sorting dataJan 31 2012Since it was first published 30 years ago, Chi et al.'s seminal paper on expert and novice categorization of introductory problems led to a plethora of follow-up studies within and outside of the area of physics [Chi et al. Cognitive Science 5, 121 - ... More
Cyg OB2 #5: When three stars are just not enoughNov 03 2010Archival observations from the Very Large Array (VLA) at frequencies between 1.4 GHz and 43 GHz of the 6.6-day O6.5-7+O5.5-6 binary Cyg OB2 #5 over 20 years are re-examined. The aim is to determine the location and character of its known variable radio ... More
WR146 - observing the OB-type companionMar 03 2000We present new radio and optical observations of the colliding-wind system WR146 aimed at understanding the nature of the companion to the Wolf-Rayet star and the collision of their winds. The radio observations reveal emission from three components: ... More
A Decomposition of Parking Functions by Undesired SpacesFeb 05 2016There is a well-known bijection between parking functions of a fixed length and maximal chains of the noncrossing partition lattice which we can use to associate to each set of parking functions a poset whose Hasse diagram is the union of the corresponding ... More
A Model-Based Approach to Climate Reconstruction Using Tree-Ring DataOct 09 2015Quantifying long-term historical climate is fundamental to understanding recent climate change. Most instrumentally recorded climate data are only available for the past 200 years, so proxy observations from natural archives are often considered. We describe ... More
Geometric Endoscopy and Mirror SymmetryOct 31 2007Apr 05 2008The geometric Langlands correspondence has been interpreted as the mirror symmetry of the Hitchin fibrations for two dual reductive groups. This mirror symmetry, in turn, reduces to T-duality on the generic Hitchin fibers, which are smooth tori. In this ... More
An Erupting Classical Nova in a Globular Cluster of M87Jan 21 2004Only one certain classical nova eruption has ever been detected inside a globular cluster - nova 1860 A.D. (T Sco) in M80. During a survey of M87 we have detected an erupting star coincident (to within 0.08 pixels) with a globular cluster of that giant ... More
Use of a Virtual Laboratory to plan, execute and analyse Neutron Strain Scanning experimentsOct 20 2002The new generation of dedicated Engineering Strain Scanners at neutron facilities such as ENGIN-X at ISIS and SMARTS at LANSCE offer considerable increases in both the throughput of samples and the density of measurements which are feasible within each ... More
How much of the outgoing radiation can be intercepted by Schwarzschildean black holes?Sep 11 2000The Schwarzschild spacetime is for electromagnetic waves like a nonuniform medium with a varying refraction index. A fraction of an outgoing radiation scatters off the curvature of the geometry and can be intercepted by a gravitational center. The amount ... More
Global solutions of a free boundary problem for selfgravitating scalar fieldsJun 01 1995Apr 12 1996The weak cosmic censorship hypothesis can be understood as a statement that there exists a global Cauchy evolution of a selfgravitating system outside an event horizon. The resulting Cauchy problem has a free null-like inner boundary. We study a selfgravitating ... More