Results for "Doug Lisman"

total 432took 0.13s
Maximized ExoEarth Candidate Yields for StarshadesMay 16 2016The design and scale of a future mission to directly image and characterize potentially Earth-like planets will be impacted, to some degree, by the expected yield of such planets. Recent efforts to increase the estimated yields, by creating observation ... More
Homeomorphism of S^1 and FactorizationAug 23 2014For each $n > 0$ there is a one complex parameter family of homeomorphisms of the circle consisting of linear fractional transformations `conjugated by $z \to z^n$'. We show that these families are free of relations, which determines the structure of ... More
On invariant measures for the group of diffeomorphisms of the circleDec 29 1996In a previous paper the author constructed biinvariant measures (possibly having values in a line bundle) for a loop group LK (with compact simply connected K) acting on the formal completion of its complexification LG. One motivation for this was to ... More
Spectrum Results with Kogut-Susskind QuarksOct 04 2001Nov 27 2001I summarize recent developments in spectrum calculations using Kogut-Susskind quarks. Theoretical developments include one-loop computations with improved actions. I present some recent simulation results, mostly from a MILC collaboration project using ... More
Scaling functions for O(4) in three dimensionsJul 31 1996Monte Carlo simulation using a cluster algorithm is used to compute the scaling part of the free energy for a three dimensional O(4) spin model. The results are relevant for analysis of lattice studies of high temperature QCD.
Solving for Root Subgroup Coordinates: The SU(2) CaseSep 19 2015Previously we showed that a loop in a simply connected compact Lie group K has a unique triangular factorization if and only if the loop has a unique root subgroup factorization (relative to a choice of a reduced sequence of simple reflections in the ... More
Rings of $SL_2({\mathbb C})$-Characters and the Kauffman Bracket Skein ModuleApr 20 1996Let $M$ be a compact orientable 3-manifold. The set of characters of $SL_2({\mathbb C})$ representations of the fundamental group of $M$ forms a closed affine algebraic set. We show that its coordinate ring is isomorphic to a specialization of the Kauffman ... More
The radial part of the zero-mode Hamiltonian for sigma models with group target spaceMar 28 2004We use geometric arguments to derive a possible form for the radial part of the ``zero-mode Hamiltonian'' for the two dimensional sigma model with target space S^3, or more generally a compact simply connected Lie group.
An invariant measure for the loop space of a simply connected compact symmetric spaceSep 04 2004Let X denote a simply connected compact Riemannian symmetric space, U the universal covering of the identity component of the group of automorphisms of X, and LU the loop group of U. In this paper we prove the existence (and conjecture the uniqueness) ... More
Asymptotic freedom of general relativity and its possible consequencesMay 24 2000The formation of singularities in certain situations, such as the collapse of massive stars, is one of the unresolved issues in classical general relativity. Although no complete theory of quantum gravity exists it is often suggested that quantum gravity ... More
Complex groups and root subgroup factorizationJul 24 2017Dec 26 2017Root subgroup factorization is a refinement of triangular (or LDU) factorization. For a complex reductive Lie group, and a choice of reduced factorization of the longest Weyl group element, the forward map from root subgroup coordinates to triangular ... More
Invariant measures for unitary forms of Kac-Moody groups, Parts I-IIIOct 09 1995The purpose of this paper is to describe some conjectures and results on the existence and uniqueness of invariant measures on formal completions of Kac-Moody groups and associated homogeneous spaces. Existence is rigorously established in all affine ... More
Glueball SpinDec 15 1999Apr 02 2001The spin of a glueball is usually taken as coming from the spin (and possibly the orbital angular momentum) of its constituent gluons. In light of the difficulties in accounting for the spin of the proton from its constituent quarks, the spin of glueballs ... More
Large Focal Plane Arrays for Future MissionsApr 13 2009We outline the challenges associated with the development and construction of large focal plane arrays for use both on the ground and in space. Using lessons learned from existing JPL-led and ASU/JPL partnership efforts to develop technology for, and ... More
Design of a telescope-occulter system for THEIADec 15 2009The Telescope for Habitable Exoplanets and Interstellar/Intergalactic Astronomy (THEIA) is a mission concept study for a flagship-class telescope-occulter system to search for terrestrial planets and perform general astrophysics with a space-based 4m ... More
Playing Modeling Games in the Science Classroom: The Case for Disciplinary IntegrationJul 18 2016We extend the theory of disciplinary integration of games for science education beyond the virtual world of games, and identify two key themes of a practice-based theoretical commitment to science learning: (1) materiality in the classroom and (2) iterative ... More
Discussion of: A statistical analysis of multiple temperature proxies: Are reconstructions of surface temperatures over the last 1000 years reliable?May 03 2011Discussion of "A statistical analysis of multiple temperature proxies: Are reconstructions of surface temperatures over the last 1000 years reliable?" by B.B. McShane and A.J. Wyner [arXiv:1104.4002]
Large Area Mapping at 850 Microns. V. Analysis of the Clump Distribution in the Orion A South Molecular CloudSep 06 2006We present results from a 2300 arcmin^2 survey of the Orion A molecular cloud at 450 and 850 micron using the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope. The region mapped lies directly south of the OMC1 cloud ... More
Loops in SU(2), Riemann Surfaces, and Factorization, IApr 03 2015Mar 08 2016In previous work we showed that a loop $g\colon S^1 \to {\rm SU}(2)$ has a triangular factorization if and only if the loop $g$ has a root subgroup factorization. In this paper we present generalizations in which the unit disk and its double, the sphere, ... More
MCMC-Based Inference in the Era of Big Data: A Fundamental Analysis of the Convergence Complexity of High-Dimensional ChainsAug 05 2015Aug 27 2015Markov chain Monte Carlo (MCMC) lies at the core of modern Bayesian methodology, much of which would be impossible without it. Thus, the convergence properties of MCMCs have received significant attention, and in particular, proving (geometric) ergodicity ... More
Loops in SL(2,C) and FactorizationJul 03 2017Sep 18 2017In previous work we proved that for a SU(2,C) valued loop having the critical degree of smoothness (one half of a derivative in the L^2 Sobolev sense), the following are equivalent: (1) the Toeplitz and shifted Toeplitz operators associated to the loop ... More
A 3D fast algorithm for computing Lagrangian coherent structures via ridge trackingFeb 23 2012Lagrangian coherent structures (LCS) in fluid flows appear as co-dimension one ridges of the finite time Lyapunov exponent (FTLE) field. In three- dimensions this means two-dimensional ridges. A fast algorithm is presented here to locate and extract such ... More
Observations on the flow structures and transport in a warm-core ring in the Gulf of MexicoSep 17 2013This study presents several new observations from the study of a warm-core ring (WCR) in the Gulf of Mexico based on the ECCO2 global ocean simulation. Using Lagrangian coherent structures (LCS) techniques to investigate this flow reveals a pattern of ... More
Finite models, stability, and Ramsey's theoremAug 29 1996We prove some results on the border of Ramsey theory (finite partition calculus) and model theory. Also a beginning of classification theory of finite models in undertaken.
Werner's Measure on Self-Avoiding Loops and WeldingJan 12 2014Aug 04 2014Werner's conformally invariant family of measures on self-avoiding loops on Riemann surfaces is determined by a single measure $\mu_0$ on self-avoiding loops in ${\mathbb C} \setminus\{0\}$ which surround $0$. Our first major objective is to show that ... More
Improved method for calculating nucleon strangenessNov 24 2010The strange quark content of the nucleon, as well as other matrix elements, can be calculated on the lattice by examining correlations between the nucleon propagator and the quark condensate. The largest contribution to statistical error comes from fluctuations ... More
The strange quark content of the nucleon in 2+1 flavor lattice QCDDec 06 2009The strangeness of the nucleon, <N|ss|N> - <0|ss|0>, is a quantity of interest for interpreting the results of dark matter detection experiments as well as for exploring the structure of the nucleon itself. We present a calculation of this quantity in ... More
Fast Bayesian Lasso for High-Dimensional RegressionSep 12 2015The lasso (Tibshirani, 1996) is an essential tool in modern high-dimensional regression and variable selection. The Bayesian lasso of Park and Casella (2008) interprets the lasso objective function as a posterior under a Laplace prior and proposes a three-step ... More
Tests of Improved Kogut-Susskind Fermion ActionsSep 18 1998Improved Kogut-Susskind quark actions containing repeatedly smeared links are studied to address the issue of flavor symmetry restoration. As a measure of the flavor symmetry restoration the mass spectrum of all the pions is computed. We present results ... More
Loops in noncompact groups and factorizationJan 02 2015May 15 2015In [11] we showed that a loop in a simply connected compact Lie group $\dot{U}$ has a unique Birkhoff (or triangular) factorization if and only if the loop has a unique root subgroup factorization (relative to a choice of a reduced sequence of simple ... More
Homeomorphism of S^1 and FactorizationAug 23 2014Dec 18 2018For each $n > 0$ there is a one complex parameter family of homeomorphisms of the circle consisting of linear fractional transformations `conjugated by $z \to z^n$'. We show that these families are free of relations, which determines the structure of ... More
Testing improved actions for dynamical Kogut-Susskind quarksMay 11 1998We extend tests of "Naik" and "fat link" improvements of the Kogut-Susskind quark action to full QCD simulations, and verify that the improvements previously demonstrated in the quenched approximation apply also to dynamical quark simulations. We extend ... More
Ontology Usage at ZFINDec 09 2010The Zebrafish Model Organism Database (ZFIN) provides a Web resource of zebrafish genomic, genetic, developmental, and phenotypic data. Four different ontologies are currently used to annotate data to the most specific term available facilitating a better ... More
Hybrid configuration content of heavy S-wave mesonsMay 08 2003Sep 05 2003We use the non-relativistic expansion of QCD (NRQCD) on the lattice to study the lowest hybrid configuration contribution to the ground state of heavy S-wave mesons. Using lowest-order lattice NRQCD to create the heavy-quark propagators, we form a basis ... More
Gauging dual symmetryJun 29 2001Jan 10 2003The idea of gauging (i.e. making local) symmetries of a physical system is a central feature of many modern field theories. Usually, one starts with a Lagrangian for some scalar or spinor matter fields, with the Lagrangian being invariant under a global ... More
PAG2ADMG: A Novel Methodology to Enumerate Causal Graph StructuresDec 01 2016Causal graphs, such as directed acyclic graphs (DAGs) and partial ancestral graphs (PAGs), represent causal relationships among variables in a model. Methods exist for learning DAGs and PAGs from data and for converting DAGs to PAGs. However, these methods ... More
Non-compact groups of inner type and factorizationMar 29 2015We investigate Birkhoff (or triangular) factorization and (what we propose to call) root subgroup factorization for elements of a noncompact simple Lie group $G_0$ of inner type. For compact groups root subgroup factorization is related to Bott-Samelson ... More
Spatial pattern and power function deviation in a cellular automata model of an ant populationDec 29 2015A spatially explicit model previously developed to apply to a population of arboreal nesting ants in southern Mexico is explored in detail, including notions of criticality and robust criticality and expected power law adjustment.
Non-equilibration of topological charge and its effectsNov 14 2016In QCD simulations at small lattice spacings, the topological charge Q evolves very slowly and, if this quantity is not properly equilibrated, we could get incorrect results for physical quantities, or incorrect estimates of their errors. We use the known ... More
Homogeneous Poisson structures on symmetric spacesOct 24 2007Jul 03 2008We calculate, in a relatively explicit way, the Hamiltonian systems which arise from the Evens-Lu construction of homogeneous Poisson structures on both compact and noncompact type symmetric spaces. A corollary is that the Hamiltonian system arising in ... More
Exotic smooth structures on 4-manifolds with zero signatureJun 02 2010Jun 06 2010For every integer $k\geq 2$, we construct infinite families of mutually nondiffeomorphic irreducible smooth structures on the topological $4$-manifolds $(2k-1)(S^2\times S^2)$ and $(2k-1)(\CP#\CPb)$, the connected sums of $2k-1$ copies of $S^2\times S^2$ ... More
Exotic smooth structures on $S^2\times S^2$May 19 2010Jul 06 2010We construct an infinite family of mutually non-diffeomorphic irreducible smooth structures on the topological 4-manifold $S^2 \times S^2$.
Homologous Non-isotopic Symplectic Tori in Homotopy Rational Elliptic SurfacesJul 02 2003Let E(1)_K denote the closed 4-manifold that is homotopy equivalent (hence homeomorphic) to the rational elliptic surface E(1) and is obtained by performing Fintushel-Stern knot surgery on E(1) using a knot K in S^3. We construct an infinite family of ... More
Homologous non-isotopic symplectic tori in a K3-surfaceMay 14 2003Jul 14 2003For each member of an infinite family of homology classes in the K3-surface E(2), we construct infinitely many non-isotopic symplectic tori representing this homology class. This family has an infinite subset of primitive classes. We also explain how ... More
Exotic Smooth Structures on Small 4-ManifoldsJan 24 2007Mar 12 2007Let M be either CP^2#3CP^2bar or 3CP^2#5CP^2bar. We construct the first example of a simply-connected symplectic 4-manifold that is homeomorphic but not diffeomorphic to M.
The age-metallicity relationship of the Large Magellanic Cloud field star population from wide-field Washington photometryAug 19 2012We analyze ages and metallicities for some 5.5 million stars distributed throughout the Large Magellanic Cloud (LMC) main body, obtained from CCD Washington CT1 photometry. We produce a comprehensive field star Age-Metallicity Relationship (AMR) from ... More
Ergodicity of Mapping Class Group Actions on Representation Varieties, II. Surfaces with BoundaryAug 25 2000The mapping class group of a compact oriented surface of genus greater than one with boundary acts ergodically on connected components of the representation variety corresponding to a connected compact Lie group, for every choice of conjugacy class boundary ... More
On the Divergence of the Rogers-Ramanujan Continued Fraction on the Unit CircleJul 06 2001Oct 15 2001Let the continued fraction expansion of any irrational number $t \in (0,1)$ be denoted by $[0,a_{1}(t),a_{2}(t),...]$ and let the i-th convergent of this continued fraction expansion be denoted by $c_{i}(t)/d_{i}(t)$. Let \[ S=\{t \in (0,1): a_{i+1}(t) ... More
Multiplicative structure of Kauffman bracket skein module quantizationsFeb 20 1999We describe, for a few small examples, the Kauffman bracket skein algebra of a surface crossed with an interval. If the surface is a punctured torus the result is a quantization of the symmetric algebra in three variables (and an algebra closely related ... More
Ergodicity of Mapping Class Group Actions on Representation Varieties, I. Closed SurfacesJun 13 2000We prove that the mapping class group of a closed surface acts ergodically on connected components of the representation variety corresponding to a connected compact Lie group.
Polynomial Continued FractionsDec 19 2018Continued fractions whose elements are polynomial sequences have been carefully studied mostly in the cases where the degree of the numerator polynomial is less than or equal to two and the degree of the denominator polynomial is less than or equal to ... More
Sobolev Maps into Compact Lie Groups and CurvatureOct 03 2017May 30 2018These are notes on seminal work of Freed, and subsequent developments, on the curvature properties of (Sobolev Lie) groups of maps from a Riemannian manifold into a compact Lie group. We are mainly interested in critical cases which are relevant to quantum ... More
Non-isotopic Symplectic Tori in the Same Homology ClassDec 27 2002For any pair of integers $n\geq 1$ and $q\geq 2$, we construct an infinite family of mutually non-isotopic symplectic tori representing the homology class $q[F]$ of an elliptic surface E(n), where $[F]$ is the homology class of the fiber. We also show ... More
Random walks with badly approximable numbersFeb 27 2001Using the discrepancy metric, we analyze the rate of convergence of a random walk on the circle generated by d rotations, and establish sharp rates that show that badly approximable d-tuples in R^d give rise to walks with the fastest convergence. We use ... More
Symplectic tori in rational elliptic surfacesAug 28 2003Let E(1)_p denote the rational elliptic surface with a single multiple fiber f_p of multiplicity p. We construct an infinite family of homologous non-isotopic symplectic tori representing the primitive class [f_p] in E(1)_p when p>1. As a consequence, ... More
The Kauffman bracket skein module of a twist knot exteriorFeb 06 2004Feb 18 2005We compute the Kauffman bracket skein module of the complement of a twist knot, finding that it is free and infinite dimensional. The basis consists of cables of a two-component link, one component of which is a meridian of the knot. The cabling of the ... More
Exotic Smooth Structures on Small 4-Manifolds with Odd SignaturesJan 29 2007Sep 10 2009Let $M$ be $\CP#2\CPb$, $3\CP#4\CPb$ or $(2n-1)\CP#2n\CPb$ for any integer $n\geq 3$. We construct an irreducible symplectic 4-manifold homeomorphic to $M$ and also an infinite family of pairwise non-diffeomorphic irreducible non-symplectic 4-manifolds ... More
The remote detectability of Earth's biosphere through time and the importance of UV capability for characterizing habitable exoplanetsMar 13 2019Thousands of planets beyond our solar system have been discovered to date, dozens of which are rocky in composition and are orbiting within the circumstellar habitable zone of their host star. The next frontier in life detection beyond our solar system ... More
Smooth and weak synthesis of the anti-diagonal in Fourier algebras of Lie groupsSep 16 2008Let $G$ be a Lie group of dimension $n$, and let $A(G)$ be the Fourier algebra of $G$. We show that the anti-diagonal $\check{\Delta}_G=\{(g,g^{-1})\in G\times G \mid g\in G\}$ is both a set of local smooth synthesis and a set of local weak synthesis ... More
The Chen-Ruan Cohomology Ring of Mirror QuinticOct 12 2002We compute the Chen-Ruan orbifold cohomology ring of the Batyrev mirror orbifold of a smooth quintic hypersurface in 4-dimensional projective space. We identify the obstruction bundle for this example by using the Riemann bilinear relations for periods. ... More
Episodic starbursts in dwarf spheroidal galaxies: a simple modelSep 19 2011Feb 07 2012Dwarf galaxies in the Local Group appear to be stripped of their gas within 270 kpc of the host galaxy. Color-magnitude diagrams of these dwarfs, however, show clear evidence of episodic star formation (\Delta{}t ~ a few Gyr) over cosmic time. We present ... More
Halting planet migration by photoevaporation from the central sourceFeb 04 2003The recent discovery of Jupiter-mass planets orbiting at a few AU from their stars compliments earlier detections of massive planets on very small orbits. The short period orbits strongly suggest that planet migration has occurred, with the likely mechanism ... More
BLC: Private Matrix Factorization Recommenders via Automatic Group LearningSep 18 2015Mar 22 2016We propose a privacy-enhanced matrix factorization recommender that exploits the fact that users can often be grouped together by interest. This allows a form of "hiding in the crowd" privacy. We introduce a novel matrix factorization approach suited ... More
Viscous diffusion and photoevaporation of stellar disksSep 24 2002Sep 26 2002The evolution of a stellar disk under the influence of viscous evolution, photoevaporation from the central source, and photoevaporation by external stars is studied. We take the typical parameters of TTSs and the Trapezium Cluster conditions. The photoionizing ... More
Persistent Homology Transform for Modeling Shapes and SurfacesOct 03 2013Jul 15 2014In this paper we introduce a statistic, the persistent homology transform (PHT), to model surfaces in $\mathbb{R}^3$ and shapes in $\mathbb{R}^2$. This statistic is a collection of persistence diagrams - multiscale topological summaries used extensively ... More
Topological Interpretations of Lattice Gauge Field TheoryOct 01 1997We construct lattice gauge field theory based on a quantum group on a lattice of dimension 1. Innovations include a coalgebra structure on the connections, and an investigation of connections that are not distinguishable by observables. We prove that ... More
The Effect of Tidal Inflation Instability on the Mass and Dynamical Evolution of Extrasolar Planets with Ultra-Short PeriodsMar 17 2003We investigate the possibility of substantial inflation of short-period Jupiter-mass planets, as a result of their internal tidal dissipation associated with the synchronization and circularization of their orbits. We employ the simplest prescription ... More
Washington Photometry of the Globular Cluster System of NGC 4472. II. The Luminosity Function and Spatial StructureNov 18 1997Nov 21 1997We present a comprehensive study of the luminosity function and spatial structure of the globular cluster system of NGC 4472, based on deep wide field Washington CT1 CCD images. The globular cluster luminosity function shows a peak at T1=23.3 +/- 0.1 ... More
The Omega- and the strange quark massSep 20 2004Oct 05 2004Omega- correlators have been calculated on the MILC collaboration's archive of three flavor improved staggered quark lattices. The Omega- is stable under strong interactions (140 MeV below threshold). It provides a valuable consistency check on a combination ... More
Molecular Tracers of Embedded Star Formation in OphiuchusOct 21 2008In this paper we analyze nine SCUBA cores in Ophiuchus using the second-lowest rotational transitions of four molecular species (12CO, 13CO, C18O, and C17O) to search for clues to the evolutionary state and star-formation activity within each core. Specifically, ... More
Globular Clusters as Tracers of Stellar Bimodality in Elliptical Galaxies: The Case of NGC 1399Nov 02 2004Globular cluster systems (GCS) frequently show a bi-modal distribution of the cluster integrated colours. This work explores the arguments to support the idea that the same feature is shared by the diffuse stellar population of the galaxy they are associated ... More
FITS Foreign File Encapsulation ConventionJan 06 2012This document describes a FITS convention developed by the IRAF Group (D. Tody, R. Seaman, and N. Zarate) at the National Optical Astronomical Observatory (NOAO). This convention is implemented by the fgread/fgwrite tasks in the IRAF fitsutil package. ... More
Measurement of hybrid content of heavy quarkonia using lattice NRQCDMar 22 2001Aug 01 2001Using lowest-order lattice NRQCD to create heavy meson propagators and applying the spin-dependent interaction, $c_B^{} \frac{-g}{2m_q}\vec\sigma\cdot\vec{B}$, at varying intermediate time slices, we compute the off-diagonal matrix element of the Hamiltonian ... More
Determining hybrid content of heavy quarkonia using lattice nonrelativistic QCDSep 28 2001Using lowest-order lattice NRQCD to create heavy meson propagators and applying the spin-dependent interaction, $c_B^{} \frac{-g}{2m_q}\vec\sigma\cdot\vec{B}$, at varying intermediate time slices, we compute the off-diagonal matrix element of the Hamiltonian ... More
BLC: Private Matrix Factorization Recommenders via Automatic Group LearningSep 18 2015Feb 27 2017We propose a privacy-enhanced matrix factorization recommender that exploits the fact that users can often be grouped together by interest. This allows a form of "hiding in the crowd" privacy. We introduce a novel matrix factorization approach suited ... More
Induced Spin-Currents in Alkali-FilmsMar 01 2004In sandwiches of FeK and FeCs the conduction electrons in the alkali metals have a large mean free path. The experiments suggest that the specular reflection for spin up and down electrons is different at the interface yielding a spin current in the alkali ... More
Field localization and mass generation in an alternative 5-dimensional brane modelSep 18 2013Jun 11 2015This proceedings is based on a talk given at the APS DPF 2013 on an alternative 5-dimensional brane world model which is related to but has some physically distinct features from the Randall-Sundrum brane world model. The spin dependent localization of ... More
Positive Operator Valued Measures: A General Setting for FramesNov 06 2011This paper presents an overview of close parallels that exist between the theory of positive operator-valued measures (POVMs) associated with a separable Hilbert space and the theory of frames on that space, including its most important generalizations. ... More
Skein HomologyJan 17 1997For each skein module we describe a homology theory which, for any three manifold recovers the skein module at its zero level. The theory measures skein-like relations among skein relations, mimicking Hilbert's theory of syzygies. We work explicit examples ... More
Science with an ngVLA: New Frontiers in Protostellar Multiplicity with the ngVLAOct 15 2018The ngVLA will enable significant advances in our understanding of the formation and evolution of multiple star systems in the protostellar phase, building upon the breakthroughs enabled by the VLA. The high-sensitivity and resolution at 3~mm wavelengths ... More
Variants of fattening and flavor symmetry restorationMar 19 1999We study the effects of different "fat link" actions for Kogut-Susskind quarks on flavor symmetry breaking. Our method is mostly empirical - we compute the pion spectrum with different valence quark actions on common sets of sample lattices. Different ... More
Large Area Mapping at 850 Microns. IV. Analysis of the Clump Distribution in the Orion B South Molecular CloudDec 15 2005We present results from a survey of a 1300 arcmin^2 region of the Orion B South molecular cloud, including NGC 2024, NGC 2023, and the Horsehead Nebula (B33), obtained using the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell ... More
The Large and Small Scale Structures of Dust in the Star-Forming Perseus Molecular CloudFeb 03 2006May 03 2006We present an analysis of ~3.5 square degrees of submillimetre continuum and extinction data of the Perseus molecular cloud. We identify 58 clumps in the submillimetre map and we identify 39 structures (`cores') and 11 associations of structures (`super ... More
IVOA Recommendation: Table Access Protocol Version 1.0Oct 03 2011The table access protocol (TAP) defines a service protocol for accessing general table data, including astronomical catalogs as well as general database tables. Access is provided for both database and table metadata as well as for actual table data. ... More
Text Segmentation Using Exponential ModelsJun 11 1997Jun 13 1997This paper introduces a new statistical approach to partitioning text automatically into coherent segments. Our approach enlists both short-range and long-range language models to help it sniff out likely sites of topic changes in text. To aid its search, ... More
Accelerated Matrix Element Method with Parallel ComputingJul 28 2014Jul 30 2014The matrix element method utilizes ab initio calculations of probability densities as powerful discriminants for processes of interest in experimental particle physics. The method has already been used successfully at previous and current collider experiments. ... More
Generating Hard Satisfiable Formulas by Hiding Solutions DeceptivelyMar 18 2005To test incomplete search algorithms for constraint satisfaction problems such as 3-SAT, we need a source of hard, but satisfiable, benchmark instances. A simple way to do this is to choose a random truth assignment A, and then choose clauses randomly ... More
Using Numerical Simulations to Gain Insight into the Structure of SuperbubblesJan 21 1999Recent high resolution observations of Galactic superbubbles have motivated us to re-examine several classes of superbubble models. We compare three classes of hydrodynamic models (the Kompaneets approximation, the thin shell model, and numerical simulations) ... More
Dynamical Evolution and Ionization Structure of an Expanding Superbubble: Application to W4Dec 15 1998Recent observations have revealed a superbubble associated with the young stellar cluster OCl 352 near the W4 H II region: a void in H I emission (Normandeau, Taylor, and Dewdney), and a bright shell in H alpha emission (Dennison, Topasna, and Simonetti). ... More
Dynamics of Dense Cores in the Perseus Molecular CloudJul 18 2007We survey the kinematics of over one hundred and fifty candidate (and potentially star-forming) dense cores in the Perseus molecular cloud with pointed N2H+(1-0) and simultaneous C18O(2-1) observations. Our detection rate of N2H+ is 62%, rising to 84% ... More
IVOA Simple Image AccessJan 04 2016The Simple Image Access protocol (SIA) provides capabilities for the discovery, description, access, and retrieval of multi-dimensional image datasets, including 2-D images as well as datacubes of three or more dimensions. SIA data discovery is based ... More
Comprehensive Modeling of Electric Vehicles in California Demand Response MarketsApr 07 2018Electric vehicle (EV) is a significant type of distributed energy resources (DERs), that provide flexibilities to grid operators to achieve a myriad of objectives. This paper presents a comprehensive modeling framework of EVs under multiple real-world ... More
High Extinction Ratio Widely Tunable Low-Loss Integrated Si3N4 Third-Order FilterAug 21 2017We demonstrate an integrated continuously tunable third-order ring filter with a measured extinction ratio of 80dB, a 100x improvement over previously demonstrated integrated 3rd or 6th order filters. Using integrated thermal tuning elements, the filter ... More
Understanding the Kauffman bracket skein moduleApr 20 1996The Kauffman bracket skein module $K(M)$ of a 3-manifold $M$ is defined over formal power series in the variable $h$ by letting $A=e^{h/4}$. For a compact oriented surface $F$, it is shown that $K(F \times I)$ is a quantization of the $\g$-characters ... More
Young Star Clusters in the Dwarf Irregular Galaxy, UGC 7636, Interacting with the Giant Elliptical Galaxy NGC 4472Aug 24 1997We present integrated Washington CT1 photometry of 18 bright blue objects discovered in the dwarf galaxy UGC 7636 which is located 5'.5 southeast of the giant elliptical galaxy NGC 4472, the brightest galaxy in the Virgo cluster. Several lines of evidence ... More
The Interplay of Turbulence & Magnetic Fields in Star-Forming Regions: Simulations and ObservationsApr 28 2009We analyze a suite of thin sheet magnetohydrodynamical simulations based on the formulation of Basu, Ciolek, Dapp & Wurster. These simulations allow us to examine the observational consequences to a star-forming region of varying the input level of turbulence ... More
Modelling the effect of gap junctions on tissue-level cardiac electrophysiologyAug 19 2012When modelling tissue-level cardiac electrophysiology, continuum approximations to the discrete cell-level equations are used to maintain computational tractability. One of the most commonly used models is represented by the bidomain equations, the derivation ... More
Homologous Non-isotopic Symplectic Surfaces of Higher GenusJan 31 2006We construct an infinite family of homologous, non-isotopic, symplectic surfaces of any genus greater than one in a certain class of closed, simply connected, symplectic four-manifolds. Our construction is the first example of this phenomenon for surfaces ... More
Parameter estimation for computationally intensive nonlinear regression with an application to climate modelingJan 23 2009Nonlinear regression is a useful statistical tool, relating observed data and a nonlinear function of unknown parameters. When the parameter-dependent nonlinear function is computationally intensive, a straightforward regression analysis by maximum likelihood ... More
Diffusion in supersonic, turbulent, compressible flowsFeb 25 2003We investigate diffusion in supersonic, turbulent, compressible flows. Supersonic turbulence can be characterized as network of interacting shocks. We consider flows with different rms Mach numbers and where energy necessary to maintain dynamical equilibrium ... More