Results for "Kristen Coppin"

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Testing the Evolutionary Link Between SMGs and QSOs: are Submm-Detected QSOs at z~2 `Transition Objects' Between These Two Phases?Feb 02 2009Local spheroids show a relation between their masses and those of the super-massive black holes (SMBH) at their centres, indicating a link between the major phases of spheroid growth and nuclear accretion. These phases may correspond to high-z submillimetre ... More
Enhanced [CII] emission in a z=4.76 submillimetre galaxyApr 27 2011We present the detection of bright [CII] emission in the z=4.76 submillimetre galaxy LESS J033229.4-275619 using the Atacama Pathfinder EXperiment. This represents the highest redshift [CII] detection in a submm selected, star-formation dominated system. ... More
Galaxy pairs in the SDSS - XIII. The connection between enhanced star formation and molecular gas properties in galaxy mergersFeb 06 2018We investigate the connection between star formation and molecular gas properties in galaxy mergers at low redshift (z$\leq$0.06). The study we present is based on IRAM 30-m CO(1-0) observations of 11 galaxies with a close companion selected from the ... More
Testing the Evolutionary Link Between Submillimetre Galaxies and Quasars: CO Observations of QSOs at z~2Jun 03 2008Jul 08 2008We have used the IRAM Plateau de Bure mm interferometer and the UKIRT 1-5 um Imager Spectrometer to test the connection between the major phases of spheroid growth and nuclear accretion by mapping CO emission in nine submm-detected QSOs at z=1.7-2.6 with ... More
Antiderivatives Exist without IntegrationDec 05 2012We present a proof that any continuous function with domain including a closed interval yields an antiderivative of that function on that interval. This is done without the need of any integration comparable to that of Riemann, Cauchy, or Darboux. The ... More
An 850-micron SCUBA map of the Groth Strip and reliable source extractionDec 10 2004We present an 850-micron map and list of candidate sources in a 70 arcmin^2 sub-area of the Groth Strip observed using SCUBA. We initially detect 7 candidate sources with signal-to-noise ratios (SNRs) between 3.0 and 3.5 and 4 candidate sources with SNR ... More
Advection-Dominated Accretion Onto Weakly-Magnetized White DwarfsJul 13 2000The boundary layers of weakly-magnetized white dwarfs (WDs) accreting at rates <=10^16 g/s are radially extended, hot, optically-thin, and they advect some of their internally-dissipated energy (Narayan & Popham 1993). Motivated by this, I construct here ... More
Hydra group doubles are not residually finiteJul 09 2015Jul 30 2015In 2013, Kharlampovich, Myasnikov, and Sapir constructed the first examples of finitely presented residually finite groups with large Dehn functions. Given any recursive function $f$, they produce a finitely presented residually finite group with Dehn ... More
A rank inequality for the knot Floer homology of double branched coversJul 11 2011Apr 29 2013Given a knot K in S^3, let \Sigma(K) be the double branched cover of S^3 over K. We show there is a spectral sequence whose E^1 page is (\hat{HFK}(\Sigma(K), K) \otimes V^{n-1}) \otimes \mathbb Z_2((q)), for V a \mathbb Z_2-vector space of dimension two, ... More
A spectral sequence of the Floer cohomology of symplectomorphisms of trivial polarization classSep 21 2014Jun 17 2016Let $M$ be an exact symplectic manifold equal to a symplectization near infinity and having stably trivializable tangent bundle, and $\phi$ be an exact symplectomorphism of $M$ which, near infinity, is equal to either the identity or the symplectization ... More
Thermo-Resistive Instability of Hot Planetary AtmospheresJun 15 2012The atmospheres of hot Jupiters and other strongly-forced exoplanets are susceptible to a thermal instability in the presence of ohmic dissipation, weak magnetic drag and strong winds. The instability occurs in radiatively-dominated atmospheric regions ... More
Differential Rotation in Weakly-Magnetized Neutron Star AtmospheresFeb 23 2004May 17 2004The atmospheres of weakly-magnetized neutron stars expand hydrostatically and rotate differentially during thermonuclear X-ray bursts. Differential rotation is probably related to the frequency drifts of millisecond burst oscillations exhibited by about ... More
Viscosity Mechanisms in Accretion DisksSep 01 2000The self-sustained turbulence which develops in magnetized accretion disks is suppressed in the weakly-ionized, quiescent disks of close binary stars. Because accretion still proceeds during quiescence, another viscosity mechanism operates in these systems. ... More
An Equivariant Tensor Product on Mackey FunctorsAug 17 2015Aug 03 2017For all subgroups $H$ of a cyclic $p$-group $G$ we define norm functors that build a $G$-Mackey functor from an $H$-Mackey functor. We give an explicit construction of these functors in terms of generators and relations based solely on the intrinsic, ... More
Black Hole Accretion Disks On The EdgeApr 23 2003Jun 20 2003The local axisymmetric stability of hydrodynamical and magnetized, nearly-Keplerian gaseous accretion disks around non-rotating black holes is examined in the vicinity of the classical marginally-stable orbit (at radii ~ R_ms). An approximate Paczynski-Wiita ... More
Probing Distant Massive Black Holes with LISAJan 20 2003Idealized models are used to illustrate the potential of the Laser Interferometer Space Antenna (LISA) as a probe of the largely unknown population of cosmologically-distant Massive Black Holes (MBHs) and as a tool to measure their masses with unprecedented ... More
Climate Stability of Habitable Earth-like PlanetsNov 20 2014The carbon-silicate cycle regulates the atmospheric $CO_2$ content of terrestrial planets on geological timescales through a balance between the rates of $CO_2$ volcanic outgassing and planetary intake from rock weathering. It is thought to act as an ... More
Atmospheric Circulation and Composition of GJ1214bSep 07 2011Nov 30 2011The exoplanet GJ1214b presents an interesting example of compositional degeneracy for low-mass planets. Its atmosphere may be composed of water, super-solar or solar metallicity material. We present atmospheric circulation models of GJ1214b for these ... More
An Equivariant Tensor Product on Mackey FunctorsAug 17 2015Aug 01 2016For all subgroups $H$ of a cyclic $p$-group $G$ we define norm functors that build a $G$-Mackey functor from an $H$-Mackey functor. We give an explicit construction of these functors in terms of generators and relations based solely on the intrinsic, ... More
Localization and the link Floer homology of doubly-periodic knotsJun 26 2012Oct 07 2015A knot \widetilde{K} \subset S^3 is q-periodic if there is a \mathbb Z_q-action preserving \widetilde{K} whose fixed set is an unknot U. The quotient of \widetilde{K} under the action is a second knot K. We construct equivariant Heegaard diagrams for ... More
Water-Trapped WorldsApr 24 2013Jul 08 2013Although tidally-locked habitable planets orbiting nearby M-dwarf stars are among the best astronomical targets to search for extrasolar life, they may also be deficient in volatiles and water. Climate models for this class of planets show atmospheric ... More
Magnetic Scaling Laws for the Atmospheres of Hot Giant ExoplanetsAug 17 2011Nov 12 2011We present scaling laws for advection, radiation, magnetic drag and ohmic dissipation in the atmospheres of hot giant exoplanets. In the limit of weak thermal ionization, ohmic dissipation increases with the planetary equilibrium temperature (T_eq >~ ... More
The Quiescence of Dwarf Novae and X-ray TransientsAug 17 2001Our understanding of the structure and properties of accretion disks in quiescent Dwarf Novae and X-ray Transients is very limited. Observations during quiescence challenge some of the standard Disk Instability Model (DIM) predictions. Our ignorance of ... More
Hot Accretion With Saturated ConductionJul 08 2005Observations of the hot gas surrounding Sgr A* and a few other nearby galactic nuclei imply electron and proton mean free paths comparable to the gas capture radius: hot accretion likely proceeds under weakly-collisional conditions in these systems. As ... More
Black Hole Accretion in Transient X-Ray BinariesNov 25 2001Nov 28 2001Recent work on the modes of accretion onto black holes (BHs) in Soft X-Ray Transients (SXTs) is reviewed, with an emphasis on uncertainties affecting models of accretion during quiescence (inner hot flow, outer thin disk). Various interpretations of the ... More
Evolving hypersurfaces by their inverse null mean curvatureNov 22 2012We introduce a new geometric evolution equation for hypersurfaces in asymptotically flat spacetime initial data sets, that unites the theory of marginally outer trapped surfaces (MOTS) with the study of inverse mean curvature flow in asymptotically flat ... More
Starburst or AGN Dominance in Submillimetre-Luminous Candidate AGN?Jan 20 2010It is widely believed that ultraluminous infrared (IR) galaxies and active galactic nuclei (AGN) activity are triggered by galaxy interactions and merging, with the peak of activity occurring at z~2, where submillimetre galaxies are thousands of times ... More
CO interferometry of gas-rich spiral galaxies in the outskirts of an intermediate redshift clusterFeb 16 2009We present IRAM Plateau de Bure Interferometer 3mm observations of CO(1-0) emission in two 24um-selected starburst galaxies in the outskirts (2-3xR_virial) of the rich cluster Cl0024+16 (z=0.395). The galaxies' inferred far-infrared luminosities place ... More
Taking Census of Massive, Star-Forming Galaxies formed <1 Gyr After the Big BangMar 13 2019Two decades of effort have been poured into both single-dish and interferometric millimeter-wave surveys of the sky to infer the volume density of dusty star-forming galaxies (DSFGs, with SFR>100M$_\odot$ yr$^{-1}$) over cosmic time. Though obscured galaxies ... More
Submillimetre Constraints on Hyper-Extremely Red Objects in the Subaru Deep FieldJul 05 2004We have mapped the submillimetre wavelength continuum emission from the Subaru Deep Field (SDF) at 450 and 850 microns with the Submillimetre Common-User Bolometer Array (SCUBA) detector on the James Clerk Maxwell Telescope (JCMT). The near-IR image of ... More
An ALMA Survey of Submillimeter Galaxies in the Extended Chandra Deep Field South: The Redshift Distribution and Evolution of Submillimeter GalaxiesOct 23 2013Apr 29 2014We present the first photometric redshift distribution for a large unbiased sample of 870um selected submillimeter galaxies (SMGs) with robust identifications based on observations with the Atacama Large Millimeter Array (ALMA). In our analysis we consider ... More
An ALMA Survey of Submillimetre Galaxies in the Extended Chandra Deep Field South: The Far-Infrared Properties of SMGsOct 23 2013Apr 22 2014We exploit ALMA 870um (345GHz) observations of submillimetre sources in the Extended Chandra Deep Field South to investigate the far-infrared properties of high-redshift submillimetre galaxies (SMGs). Using the precisely located 870um ALMA positions of ... More
Strong polarization-induced reduction of addition energies in single-molecule nanojunctionsSep 10 2008We address polarization-induced renormalization of molecular levels in solid-state based single-molecule transistors and focus on an organic conjugate molecule where a surprisingly large reduction of the addition energy has been observed. We have developed ... More
Dynamical Habitability of Known Extrasolar Planetary SystemsSep 30 2002Habitability is usually defined as the requirement for a terrestrial planet's atmosphere to sustain liquid water. This definition can be complemented by the dynamical requirement that other planets in the system do not gravitationally perturb terrestrial ... More
Atmospheric Circulation of Hot Jupiters: A Shallow Three-Dimensional ModelSep 09 2008May 12 2009Remote observing of exoplanetary atmospheres is now possible, offering us access to circulation regimes unlike any of the familiar Solar System cases. Atmospheric circulation models are being developed to study these new regimes but model validations ... More
Radiation-Hydrodynamics of Hot Jupiter AtmospheresOct 07 2009Mar 08 2010Radiative transfer in planetary atmospheres is usually treated in the static limit, i.e., neglecting atmospheric motions. We argue that hot Jupiter atmospheres, with possibly fast (sonic) wind speeds, may require a more strongly coupled treatment, formally ... More
Three Dimensional Modeling of Hot Jupiter Atmospheric FlowsJul 15 2009Mar 26 2010We present a three dimensional hot Jupiter model, extending from 200 bar to 1 mbar, using the Intermediate General Circulation Model from the University of Reading. Our horizontal spectral resolution is T31 (equivalent to a grid of 48x96), with 33 logarithmically ... More
Safe Artificial General Intelligence via Distributed Ledger TechnologyFeb 11 2019Background. Expert observers and artificial intelligence (AI) progression metrics indicate AI will exceed human intelligence within a few decades. Whether general AI that exceeds human capabilities (AGI) will be the single greatest boon in history or ... More
Safe Artificial General Intelligence via Distributed Ledger TechnologyFeb 11 2019Mar 02 2019Background. Expert observers and artificial intelligence (AI) progression metrics indicate AI will exceed human intelligence within a few decades. Whether general AI that exceeds human capabilities (AGI) will be the single greatest boon in history or ... More
Thinking Outside the Pool: Active Training Image Creation for Relative AttributesJan 08 2019Current wisdom suggests more labeled image data is always better, and obtaining labels is the bottleneck. Yet curating a pool of sufficiently diverse and informative images is itself a challenge. In particular, training image curation is problematic for ... More
Eventually linear partially complete resolutions over a local ring with $m^4=0$Dec 03 2012We classify the Hilbert polynomial of a local ring $(R,m)$ satisfying $m^4=0$ which admits an eventually linear doubly-infinite resolution $C$ which is 'partially' complete --- that is, for which the cohomology of $Hom_R(C,R)$ eventually vanishes. As ... More
Generalizations of a Laplacian-Type Equation in the Heisenberg Group and a Class of Grushin-Type SpacesDec 19 2011Beals, Gaveau and Greiner (1996) find the fundamental solution to a 2-Laplace-type equation in a class of sub-Riemannian spaces. This solution is related to the well-known fundamental solution to the p-Laplace equation in Grushin-type spaces (Bieske-Gong, ... More
A note on knot concordance and involutive knot Floer homologyAug 21 2017We prove that if two knots are concordant, their involutive knot Floer complexes satisfy a certain type of stable equivalence.
Atmospheres of Hot Super-EarthsSep 03 2011Nov 12 2011Hot super-Earths likely possess minimal atmospheres established through vapor saturation equilibrium with the ground. We solve the hydrodynamics of these tenuous atmospheres at the surface of Corot-7b, Kepler 10b and 55 Cnc-e, including idealized treatments ... More
On The Dark Side of Quasar EvolutionMay 17 2004Jul 01 2004Recent improved determinations of the mass density rho_BH of supermassive black holes (SMBHs) in the local universe have allowed accurate comparisons of rho_BH with the amount of light received from past quasar activity. These comparisons support the ... More
The Mass Budget of Merging QuasarsMay 17 2004Two spectacular results emerging from recent studies of nearby dead quasars and distant active quasars are (i) the existence of tight relations between the masses of black holes (BHs) and the properties of their host galaxies (spheroid luminosity or velocity ... More
Low-Mass Proto-Planet Migration in T-Tauri Alpha-DisksOct 07 2003Mar 06 2004We present detailed estimates of ''type-I'' migration rates for low-mass proto-planets embedded in steady-state T-Tauri alpha-disks, based on Lindblad torque calculations ignoring feedback on the disk. Differences in migration rates for several plausible ... More
2.5D Visual SoundDec 11 2018Apr 09 2019Binaural audio provides a listener with 3D sound sensation, allowing a rich perceptual experience of the scene. However, binaural recordings are scarcely available and require nontrivial expertise and equipment to obtain. We propose to convert common ... More
Magneto-Rotational Transport in the Early SunJun 14 2006Angular momentum transport must have occurred in the Sun's radiative zone to explain its current solid body rotation. We survey the stability of the early Sun's radiative zone with respect to diffusive rotational instabilities, for a variety of plausible ... More
Activity From Tidal Disruptions in Galactic NucleiOct 05 2001Nov 14 2001The tidal disruption of a star by a supermassive black hole is expected to lead to a short bright flare followed by an extended period of low-level emission. Existing models of the late-time accretion of the stellar debris via a thin disk imply that the ... More
A General Circulation Model for Gaseous Exoplanets with Double-Gray Radiative TransferDec 07 2011We present a new version of our code for modeling the atmospheric circulation on gaseous exoplanets, now employing a "double-gray" radiative transfer scheme, which self-consistently solves for fluxes and heating throughout the atmosphere, including the ... More
Full counting statistics and shot noise of cotunneling in quantum dots and single-molecule transistorsApr 05 2015Jun 03 2015We develop a conceptually simple scheme based on a master-equation approach to evaluate the full-counting statistics (FCS) of elastic and inelastic off-resonant tunneling (cotunneling) in quantum dots (QDs) and molecules. We demonstrate the method by ... More
2.5D Visual SoundDec 11 2018Mar 07 2019Binaural audio provides a listener with 3D sound sensation, allowing a rich perceptual experience of the scene. However, binaural recordings are scarcely available and require nontrivial expertise and equipment to obtain. We propose to convert common ... More
Seeing Invisible Poses: Estimating 3D Body Pose from Egocentric VideoMar 24 2016Understanding the camera wearer's activity is central to egocentric vision, yet one key facet of that activity is inherently invisible to the camera--the wearer's body pose. Prior work focuses on estimating the pose of hands and arms when they come into ... More
Topics in Applied Mathematics and Nonlinear WavesApr 15 2019The selection of topics in this text has formed the core of a one semester course in applied mathematics at the Arctic University of Norway that has been running continuously since the 1970s. The class has, during its existence, drawn participants from ... More
The thermodynamics of lightMay 05 2018These notes introduce some of the basic mathematical and physical tools neccessary for theoretical investigations into the thermodynamics properties of light in cavities. The notes were created while preparing for a project in this area were we noted ... More
Involutive Heegaard Floer homologyJul 01 2015Aug 10 2016Using the conjugation symmetry on Heegaard Floer complexes, we define a three-manifold invariant called involutive Heegaard Floer homology, which is meant to correspond to $\mathbb{Z}_4$-equivariant Seiberg-Witten Floer homology. Further, we obtain two ... More
Probing Gravity with Spacetime SirensAug 31 2007A gravitational observatory such as LISA will detect coalescing pairs of massive black holes, accurately measure their luminosity distance and help identify a host galaxy or an electromagnetic counterpart. If dark energy is a manifestation of modified ... More
On the Cosmological Evolution of the Luminosity Function and the Accretion Rate of QuasarsOct 27 1998Oct 12 1999We consider a class of models for the redshift evolution (between $0\lsim z \lsim 4$) of the observed optical and X-ray quasar luminosity functions (LFs), with the following assumptions: (i) the mass-function of dark matter halos follows the Press-Schechter ... More
Visual Question: Predicting If a Crowd Will Agree on the AnswerAug 29 2016Visual question answering (VQA) systems are emerging from a desire to empower users to ask any natural language question about visual content and receive a valid answer in response. However, close examination of the VQA problem reveals an unavoidable, ... More
Time-Dependent Models for the Afterglows of Massive Black Hole MergersDec 10 2009Mar 17 2010The Laser Interferometer Space Antenna (LISA) will detect gravitational wave signals from coalescing pairs of massive black holes in the total mass range (10^5 - 10^7)/Msol out to cosmological distances. Identifying and monitoring the electromagnetic ... More
A lattice QCD study of generalized gluelumpsSep 06 2013Jan 09 2014Proposals for physics beyond the standard model often include new colored particles at or beyond the scale of electroweak symmetry breaking. Any new particle with a sufficient lifetime will bind with standard model gluons and quarks to form a spectrum ... More
Snap Angle Prediction for 360$^{\circ}$ PanoramasMar 31 2018Aug 12 2018360$^{\circ}$ panoramas are a rich medium, yet notoriously difficult to visualize in the 2D image plane. We explore how intelligent rotations of a spherical image may enable content-aware projection with fewer perceptible distortions. Whereas existing ... More
Theory of light emission from quantum noise in plasmonic contacts: above-threshold emission from higher-order electron-plasmon scatteringDec 02 2014Feb 21 2015We develop a theoretical framework for the description of light emission from plasmonic contacts based on the nonequilibrium Green function formalism. Our theory establishes a fundamental link between the finite-frequency quantum noise and AC conductance ... More
Semantic Jitter: Dense Supervision for Visual Comparisons via Synthetic ImagesDec 19 2016Apr 27 2017Distinguishing subtle differences in attributes is valuable, yet learning to make visual comparisons remains non-trivial. Not only is the number of possible comparisons quadratic in the number of training images, but also access to images adequately spanning ... More
The HiZELS/UKIRT large area survey for bright Lyman-alpha emitters at z~9Nov 25 2009Nov 28 2009We present the largest area survey to date (1.4 deg2) for Lyman-alpha emitters (LAEs) at z~9, as part of the Hi-z Emission Line Survey (HiZELS). The survey, which primarily targets H-alpha emitters at z < 3, uses the Wide Field CAMera on the United Kingdom ... More
Equilibrium probability distribution of a conductive sphere's floating charge in a collisionless, drifting Maxwellian plasmaMay 24 2013Jan 27 2014A dust grain in a plasma has a fluctuating electric charge, and past work concludes that spherical grains in a stationary, collisionless plasma have an essentially Gaussian charge probability distribution. This paper extends that work to flowing plasmas ... More
Ionization, Magneto-rotational, and Gravitational Instabilities in Thin Accretion Disks Around Supermassive Black HolesAug 23 2000Nov 28 2000We consider the combined role of the thermal ionization, magneto-rotational and gravitational instabilities in thin accretion disks around supermassive black holes. We find that in the portions of the disk unstable to the ionization instability, the gas ... More
Discovering Attribute Shades of Meaning with the CrowdMay 15 2015To learn semantic attributes, existing methods typically train one discriminative model for each word in a vocabulary of nameable properties. However, this "one model per word" assumption is problematic: while a word might have a precise linguistic definition, ... More
Null mean curvature flow and outermost MOTSMar 13 2015We study the evolution of hypersurfaces in spacetime initial data sets by their null mean curvature. A theory of weak solutions is developed using the level-set approach. Starting from an arbitrary mean convex, outer untapped hypersurface $\partial\Omega_0$, ... More
Look-ahead before you leap: end-to-end active recognition by forecasting the effect of motionApr 30 2016Aug 05 2016Visual recognition systems mounted on autonomous moving agents face the challenge of unconstrained data, but simultaneously have the opportunity to improve their performance by moving to acquire new views of test data. In this work, we first show how ... More
Explanation-Based AuditingSep 30 2011To comply with emerging privacy laws and regulations, it has become common for applications like electronic health records systems (EHRs) to collect access logs, which record each time a user (e.g., a hospital employee) accesses a piece of sensitive data ... More
An Introduction to Partial Differential EquationsJan 10 2019The field of partial differential equations (PDEs) is vast in size and diversity. The basic reason for this is that essentially all fundamental laws of physics are formulated in terms of PDEs. In addition, approximations to these fundamental laws, that ... More
Existence of Totally Reflexive Modules via Gorenstein HomomorphismsJan 13 2011May 24 2011We define, via Gorenstein homomorphisms, a class of local rings over which there exist non-trivial totally reflexive modules. We also provide a general construction of such rings, which indicates their abundance.
Centralizers of Commuting Elements in Compact Lie GroupsJun 19 2010The moduli space for a flat G-bundle over the two-torus is completely determined by its holonomy representation. When G is compact, connected, and simply connected, we show that the moduli space is homeomorphic to a product of two tori mod the action ... More
A submillimetre galaxy at z=4.76 in the LABOCA survey of the Extended Chandra Deep Field SouthFeb 25 2009We report on the identification of the highest redshift submm-selected source currently known: LESSJ033229.4-275619. This source was detected in the Large Apex BOlometer CAmera (LABOCA) Extended Chandra Deep Field South (ECDFS) Submillimetre Survey (LESS), ... More
Collaborative model of interaction and Unmanned Vehicle Systems' interfaceJun 04 2008The interface for the next generation of Unmanned Vehicle Systems should be an interface with multi-modal displays and input controls. Then, the role of the interface will not be restricted to be a support of the interactions between the ground operator ... More
On the origin of episodic accretion in Dwarf NovaeOct 22 1997We show that dwarf nova disks in quiescence have rather low magnetic Reynolds number, of order 10^3. Numerical simulations of magnetized accretion disks suggest that under these conditions magnetohydrodynamic turbulence and the associated angular momentum ... More
Signatures of adatom effects in the quasiparticle spectrum of Li-doped grapheneApr 17 2019We study the spectral function and quasiparticle scattering in Li-decorated graphene (Li@graphene) with an atomistic $T$-matrix formalism and uncover adatom-induced spectral effects which shed light on experimentally observed ARPES features. From transport ... More
Information, Community, and Action: How Nonprofit Organizations Use Social MediaApr 15 2012The rapid diffusion of "microblogging" services such as Twitter is ushering in a new era of possibilities for organizations to communicate with and engage their core stakeholders and the general public. To enhance understanding of the communicative functions ... More
On the Gröbner complexity of matricesAug 31 2007In this paper we show that if for an integer matrix A the universal Gr\"obner basis of the associated toric ideal \Ideal_A coincides with the Graver basis of A, then the Gr\"obner complexity u(A) and the Graver complexity g(A) of its higher Lawrence liftings ... More
The Origin of Solar Activity in the TachoclineAug 27 2007Solar active regions, produced by the emergence of tubes of strong magnetic field in the photosphere, are restricted to within 35 degrees of the solar equator. The nature of the dynamo processes that create and renew these fields, and are therefore responsible ... More
Predicting Important Objects for Egocentric Video SummarizationMay 18 2015We present a video summarization approach for egocentric or "wearable" camera data. Given hours of video, the proposed method produces a compact storyboard summary of the camera wearer's day. In contrast to traditional keyframe selection techniques, the ... More
Learning Compressible 360° Video IsomersDec 12 2017Standard video encoders developed for conventional narrow field-of-view video are widely applied to 360{\deg} video as well, with reasonable results. However, while this approach commits arbitrarily to a projection of the spherical frames, we observe ... More
On the X-ray Spectra of Anomalous X-ray Pulsars and Soft Gamma RepeatersJan 21 2010We revisit the apparent correlation between soft X-ray band photon index and spin-down rate nudot previously reported for Anomalous X-ray Pulsars (AXPs) and Soft Gamma Repeaters (SGRs) by Marsden & White (2001). Our analysis, improved thanks to new source ... More
Sidekick Policy Learning for Active Visual ExplorationJul 29 2018We consider an active visual exploration scenario, where an agent must intelligently select its camera motions to efficiently reconstruct the full environment from only a limited set of narrow field-of-view glimpses. While the agent has full observability ... More
Click Carving: Segmenting Objects in Video with Point ClicksJul 05 2016We present a novel form of interactive video object segmentation where a few clicks by the user helps the system produce a full spatio-temporal segmentation of the object of interest. Whereas conventional interactive pipelines take the user's initialization ... More
Bias and variance in the social structure of genderMay 13 2017The observation that individuals tend to be friends with people who are similar to themselves, commonly known as homophily, is a prominent and well-studied feature of social networks. Many machine learning methods exploit homophily to predict attributes ... More
Leaving Some Stones Unturned: Dynamic Feature Prioritization for Activity Detection in Streaming VideoApr 01 2016Current approaches for activity recognition often ignore constraints on computational resources: 1) they rely on extensive feature computation to obtain rich descriptors on all frames, and 2) they assume batch-mode access to the entire test video at once. ... More
Model Categories and Simplicial MethodsSep 19 2006Nov 28 2006There are many ways to present model categories, each with a different point of view. Here we'd like to treat model categories as a way to build and control resolutions. This an historical approach, as in his original and spectacular applications of model ... More
Golden Binary Gravitational-Wave Sources: Robust Probes of Strong-Field GravityOct 06 2004Jan 14 2005Space-born gravitational-wave interferometers such as {\it LISA} will detect the gravitational wave (GW) signal from the inspiral, plunge and ringdown phases of massive black hole binary mergers at cosmological distances. From the inspiral waves, we will ... More
The Quiescent Emission Spectrum of Cen X-4 and other X-ray Transients containing Neutron StarsOct 20 2000Apr 17 2001We use the observed optical-UV and X-ray emission spectrum of Cen X-4 during quiescence to constrain models for the accretion flow in this system. We argue that the optical-UV emission is not due to an optically-thick quiescent accretion disk, nor due ... More
Subjects and Their Objects: Localizing Interactees for a Person-Centric View of ImportanceApr 17 2016Understanding images with people often entails understanding their \emph{interactions} with other objects or people. As such, given a novel image, a vision system ought to infer which other objects/people play an important role in a given person's activity. ... More
Molecular Hydrogen in Infrared CirrusJul 25 2005We combine data from our recent FUSE survey of interstellar molecular hydrogen absorption toward 50 high-latitude AGN with COBE-corrected IRAS 100 micron emission maps to study the correlation of infrared cirrus with H2. A plot of the H2 column density ... More
Kernel Transformer Networks for Compact Spherical ConvolutionDec 07 2018Apr 09 2019Ideally, 360{\deg} imagery could inherit the deep convolutional neural networks (CNNs) already trained with great success on perspective projection images. However, existing methods to transfer CNNs from perspective to spherical images introduce significant ... More
Learning Spherical Convolution for Fast Features from 360° ImageryAug 02 2017Dec 07 2018While 360{\deg} cameras offer tremendous new possibilities in vision, graphics, and augmented reality, the spherical images they produce make core feature extraction non-trivial. Convolutional neural networks (CNNs) trained on images from perspective ... More
On the EOS formulation for light scattering. Stability, Singularity and ParallelizationDec 12 2018In this paper we discuss some of the mathematical and numerical issues that have to be addressed when calculating wave scattering using the EOS approach. The discussion is framed in context of light scattering by objects whose optical response can be ... More
Hot Accretion onto White Dwarfs in Quiescent Dwarf NovaeDec 07 2001We present dynamically consistent solutions for hot accretion onto unmagnetized, rotating white dwarfs (WDs) in five quiescent dwarf novae. The measured WD rotation rates (and other system parameters) in RX And, SS Cyg, U Gem, VW Hyi and WZ Sge imply ... More
Correlated Coulomb drag in capacitively coupled quantum-dot structuresJan 04 2016May 04 2016We study theoretically Coulomb drag in capacitively coupled quantum dots (CQDs) -- a biasdriven dot coupled to an unbiased dot where transport is due to Coulomb mediated energy transfer drag. To this end, we introduce a master-equation approach which ... More
Kernel Transformer Networks for Compact Spherical ConvolutionDec 07 2018Ideally, 360{\deg} imagery could inherit the deep convolutional neural networks (CNNs) already trained with great success on perspective projection images. However, existing methods to transfer CNNs from perspective to spherical images introduce significant ... More