Results for "Pamela Klaassen"

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The Winds from HL TauApr 25 2016Outflowing motions, whether a wind launched from the disk, a jet launched from the protostar, or the entrained molecular outflow, appear to be an ubiquitous feature of star formation. These outwards motions have a number of root causes, and how they manifest ... More
The Ionization of Accretion Flows in High Mass Star Formation: W51e2Apr 03 2008Previous observations show that the hypercompact HII region W51e2 is surrounded by a massive molecular accretion flow centered on the HII region. New observations of the H53alpha radio recombination line made with the VLA at 0.45 arc second angular resolution ... More
Rotationally Symmetric Tilings with Convex Pentagons and HexagonsSep 21 2015Jan 08 2016In contrast to many known results concerning periodic tilings of the Euclidean plane with pentagons, here tilings with rotational symmetry are investigated. A certain class of convex pentagons is introduced. It can be shown that for any given symmetry ... More
The Atacama Large Aperture Submillimeter Telescope (AtLAST)Jul 10 2019The sub-mm sky is a unique window for probing the architecture of the Universe and structures within it. From the discovery of dusty sub-mm galaxies, to the ringed nature of protostellar disks, our understanding of the formation, destruction, and evolution ... More
Evidential Value in ANOVA-Regression Results in Scientific Integrity StudiesMay 18 2014Mar 19 2015Some scientific publications are under suspicion of fabrication of data. Since humans are bad random number generators, there might be some evidential value in favor of fabrication in the statistical results as presented in such papers. In case of ANOVA-Regression ... More
On the global dimension of the endomorphism algebra of a $τ$-tilting moduleSep 18 2018We find a relationship between the global dimension of an algebra $A$ and the global dimension of the endomorphism algebra of a $\tau$-tilting module, when $A$ is of finite global dimension. We show that, in general, the global dimension of the endomorphism ... More
Tracking and vertexing at ATLASJul 20 2007Several algorithms for tracking and for primary and secondary vertex reconstruction have been developed by the ATLAS collaboration following different approaches. This has allowed a thorough cross-check of the performances of the algorithms and of the ... More
Searches for the Higgs boson in Minimal Supersymmetric CP-conserving and CP-violating Standard Model scenarios at LEPMay 12 2005It is important to study extended models containing more than one physical Higgs boson in the spectrum. In particular, Two Higgs Doublet Models (2HDMs) are attractive extensions of the SM, predicting new phenomena with the fewest new parameters. The Higgs ... More
Kostant's weight multiplicity formula and the Fibonacci numbersNov 28 2011It is well known that the dimension of a weight space for a finite dimensional representation of a simple Lie algebra is given by Kostant's weight multiplicity formula. We address the question of how many terms in the alternation contribute to the multiplicity ... More
Are molecular outflows around high-mass stars driven by ionization feedback?Sep 26 2012The formation of massive stars exceeding 10 solar masses usually results in large-scale molecular outflows. Numerical simulations, including ionization, of the formation of such stars show evidence for ionization-driven molecular outflows. We here examine ... More
Morphologies of protostellar outflows: An ALMA viewOct 28 2013The formation of stars is usually accompanied by the launching of protostellar outflows. Observations with the Atacama Large Millimetre/sub-millimetre Array (ALMA) will soon revolutionalise our understanding of the morphologies and kinematics of these ... More
Time-Domain Photometry of Protostars at Far-Infrared and Submillimeter WavelengthsMar 18 2019The majority of the ultimate main-sequence mass of a star is assembled in the protostellar phase, where a forming star is embedded in an infalling envelope and encircled by a protoplanetary disk. Studying mass accretion in protostars is thus a key to ... More
Directly observing continuum emission from self-gravitating spiral wavesFeb 03 2016We use a simple, self-consistent, self-gravitating semi-analytic disc model to conduct an examination of the parameter space in which self-gravitating discs may exist. We then use Monte-Carlo radiative transfer to generate synthetic ALMA images of these ... More
First Generation Heterodyne Instrumentation Concepts for the Atacama Large Aperture Submillimeter TelescopeJul 08 2019(abridged) The Atacama Large Aperture Submillimeter Telescope (AtLAST) project aims to build a 50-m-class submm telescope with $>1^\circ$ field of view, high in the Atacama Desert, providing fast and detailed mapping of the mm/submm sky. It will thus ... More
Semiparametrically Efficient Estimation of Euclidean Parameters under Equality ConstraintsJun 24 2016Assume a (semi)parametrically efficient estimator is given of the Euclidean parameter in a (semi)parametric model. A submodel is obtained by constraining this model in that a continuously differentiable function of the Euclidean parameter vanishes. We ... More
Outflow and Accretion in Massive Star Forming RegionsOct 19 2007In order to distinguish between the various components of massive star forming regions (i.e. infalling, outflowing and rotating gas structures) within our own Galaxy, we require high angular resolution observations which are sensitive to structures on ... More
Outflow and Infall in a Sample of Massive Star Forming RegionsApr 10 2007We present single pointing observations of SiO, HCO$^+$ and H$^{13}$CO$^+$ from the James Clerk Maxwell Telescope towards 23 massive star forming regions previously known to contain molecular outflows and ultracompact HII regions. We detected SiO towards ... More
Semiparametrically Efficient Estimation of Constrained Euclidean ParametersAug 14 2015Consider a quite arbitrary (semi)parametric model with a Euclidean parameter of interest and assume that an asymptotically (semi)parametrically efficient estimator of it is given. If the parameter of interest is known to lie on a general surface (image ... More
The ionised, radical and molecular Milky Way: spectroscopic surveys with the SKADec 17 2014The bandwith, sensitivity and sheer survey speed of the SKA offers unique potential for deep spectroscopic surveys of the Milky Way. Within the frequency bands available to the SKA lie many transitions that trace the ionised, radical and molecular components ... More
Information weighted sampling for detecting rare items in finite populations with a focus on securityOct 22 2013Frequently one has to search within a finite population for a single particular individual or item with a rare characteristic. Whether an item possesses the characteristic can only be determined by close inspection. The availability of additional information ... More
"SZ spectroscopy" in the coming decade: Galaxy cluster cosmology and astrophysics in the submillimeterMar 12 2019Sunyaev-Zeldovich (SZ) effects were first proposed in the 1970s as tools to identify the X-ray emitting hot gas inside massive clusters of galaxies and obtain their velocities relative to the cosmic microwave background (CMB). Yet it is only within the ... More
Using Terminological Knowledge Representation Languages to Manage Linguistic ResourcesMay 14 1996I examine how terminological languages can be used to manage linguistic data during NL research and development. In particular, I consider the lexical semantics task of characterizing semantic verb classes and show how the language can be extended to ... More
Numerical Range and Compressions of the ShiftOct 27 2018The numerical range of a bounded, linear operator on a Hilbert space is a set in $\mathbb{C}$ that encodes important information about the operator. In this survey paper, we first consider numerical ranges of matrices and discuss several connections with ... More
Compressions of the Shift on the Bidisk and their Numerical RangesFeb 17 2017We consider two-variable model spaces associated to rational inner functions $\Theta$ on the bidisk, which always possess canonical $z_2$-invariant subspaces $\mathcal{S}_2.$ A particularly interesting compression of the shift is the compression of multiplication ... More
Collective outflow from a small multiple stellar systemApr 22 2014The formation of high-mass stars is usually accompanied by powerful protostellar outflows. Such high-mass outflows are not simply scaled-up versions of their lower-mass counterparts, since observations suggest that the collimation degree degrades with ... More
A new characterization of the exceptional Lie algebrasMar 13 2014For a simple Lie algebra, over $\mathbb{C}$, we consider the weight which is the sum of all simple roots and denote it $\tilde{\alpha}$. We formally use Kostant's weight multiplicity formula to compute the "dimension" of the zero-weight space. In type ... More
On the adjoint representation of $\mathfrak{sl}_n$ and the Fibonacci numbersJun 07 2011We decompose the adjoint representation of $\mathfrak{sl}_{r+1}=\mathfrak {sl}_{r+1}(\mathbb C)$ by a purely combinatorial approach based on the introduction of a certain subset of the Weyl group called the \emph{Weyl alternation set} associated to a ... More
$\sqrt{n}$-consistent parameter estimation for systems of ordinary differential equations: bypassing numerical integration via smoothingJul 22 2010Jul 26 2012We consider the problem of parameter estimation for a system of ordinary differential equations from noisy observations on a solution of the system. In case the system is nonlinear, as it typically is in practical applications, an analytic solution to ... More
Looking for outflow and infall signatures in high mass star forming regionsDec 05 2011(Context) Many physical parameters change with time in star forming regions. Here we attempt to correlate changes in infall and outflow motions in high mass star forming regions with evolutionary stage using JCMT observations. (Aims) From a sample of ... More
Discrete SpacingsDec 06 2001Consider a string of $n$ positions, i.e. a discrete string of length $n$. Units of length $k$ are placed at random on this string in such a way that they do not overlap, and as often as possible, i.e. until all spacings between neighboring units have ... More
Transformation Models in High-DimensionsDec 20 2017Transformation models are a very important tool for applied statisticians and econometricians. In many applications, the dependent variable is transformed so that homogeneity or normal distribution of the error holds. In this paper, we analyze transformation ... More
Outflow and Infall in a Sample of Massive Star Forming Regions II: Large Scale KinematicsMay 22 2008We present maps of seven sources selected from Klaassen & Wilson (2007a) in SiO (J=8-7) and HCO$^+$ and H$^{13}$CO$^+$ (J=4-3) which were obtained using HARP-B on the James Clerk Maxwell Telescope. We find that four out of our seven sources have infall ... More
Speed and Accuracy of Static Image Discrimination by RatsJul 13 2012When discriminating dynamic noisy sensory signals, human and primate subjects achieve higher accuracy when they take more time to decide, an effect attributed to accumulation of evidence over time to overcome neural noise. We measured the speed and accuracy ... More
Norms of truncated Toeplitz operators and numerical radii of restricted shiftsNov 16 2017May 02 2018This paper gives a new approach to the calculation of the numerical radius of a restricted shift operator by linking it to the norm of a truncated Toeplitz operator (TTO), which can be be calculated by various methods. Further results on the norm of a ... More
Approximation by polynomials and Blaschke products having all zeros on a circleFeb 01 2010We show that a nonvanishing analytic function on a domain in the unit disc can be approximated by (a scalar multiple of) a Blaschke product whose zeros lie on a prescribed circle enclosing the domain. We also give a new proof of the analogous classical ... More
Lattice point visibility on power functionsDec 26 2017It is classically known that the proportion of lattice points visible from the origin via functions of the form $f(x)=nx$ with $n\in \mathbb{Q}$ is $\frac{1}{\zeta(2)}$ where $\zeta(s)$ is the classical Reimann zeta function. Goins, Harris, Kubik and ... More
Norms of truncated Toeplitz operators and numerical radii of restricted shiftsNov 16 2017May 16 2019This paper gives a new approach to the calculation of the numerical radius of a restricted shift operator by linking it to the norm of a truncated Toeplitz operator (TTO), which can be be calculated by various methods. Further results on the norm of a ... More
Uniform Inference in High-Dimensional Gaussian Graphical ModelsAug 30 2018Dec 03 2018Graphical models have become a very popular tool for representing dependencies within a large set of variables and are key for representing causal structures. We provide results for uniform inference on high-dimensional graphical models with the number ... More
A State Space Technique for Wildlife Position Estimation Using Non-Simultaneous Signal Strength MeasurementsMay 28 2018A novel state-space technique is presented to estimate the location and airborne movements of VHF tagged wildlife individuals with fixed VHF arrays. The approach combines a movement model (Ornstein- Uhlenbeck random process in the transverse (horizontal) ... More
Collinear features impair visual detection by ratsFeb 08 2011We measure rats' ability to detect an oriented visual target grating located between two flanking stimuli ("flankers"). Flankers varied in contrast, orientation, angular position, and sign. Rats are impaired at detecting visual targets with collinear ... More
The Ultraviolet Morphology of GalaxiesSep 16 1996Optical band images of distant (z > 0.5) galaxies, such as those of the Hubble Deep Field, record light from the rest-frame vacuum ultraviolet (< 3000 A). Because the appearance of a galaxy is a very strong function of wavelength, and especially so in ... More
A Monte Carlo study on the detection of classical order by disorder in real antiferromagnetic Ising pyrochloresMar 22 2019We use Monte Carlo simulations to evaluate the feasibility of detecting thermal order by disorder in real antiferromagnetic Ising pyrochlores frustrated by a magnetic field applied in the $[110]$ direction. Building on an ideal system with only nearest-neighbour ... More
Speed and accuracy in a visual motion discrimination task as performed by ratsJun 01 2012We find that rats, like primates and humans, perform better on the random dot motion task when they take more time to respond. We provide evidence that this improvement is due to stimulus integration. Rats increase their response latency modestly as a ... More
Nonparametric regression based on discretely sampled curvesApr 28 2016May 26 2017In the context of nonparametric regression, we study conditions under which the consistency (and rates of convergence) of estimators built from discretely sampled curves can be derived from the consistency of estimators based on the unobserved whole trajectories. ... More
Applications of EnvelopesOct 27 2018Intuitively, an envelope of a family of curves is a curve that is tangent to a member of the family at each point. Here we use envelopes of families of circles to study objects from matrix theory and hyperbolic geometry. First we explore relationships ... More
Impacts of real-time data collection on introductory algebra-based physicsSep 18 2007Including real-time data collection technology is a common practice to upgrade physics labs, and the assumption is such technology improves student learning, yet little has been done to demonstrate the effects of technology. Specific activities have been ... More
The Dirichlet Problem on Quadratic SurfacesDec 26 2002We give a fast, exact algorithm for solving Dirichlet problems with polynomial boundary functions on quadratic surfaces in R^n such as ellipsoids, elliptic cylinders, and paraboloids. To produce this algorithm, first we show that every polynomial in R^n ... More
Hard Non-Monotonic Attention for Character-Level TransductionAug 29 2018Character-level string-to-string transduction is an important component of various NLP tasks. The goal is to map an input string to an output string, where the strings may be of different lengths and have characters taken from different alphabets. Recent ... More
Repetition avoidance in products of factorsSep 05 2018Apr 27 2019We consider a variation on a classical avoidance problem from combinatorics on words that has been introduced by Mousavi and Shallit at DLT 2013. Let $\texttt{pexp}_i(w)$ be the supremum of the exponent over the products of $i$ factors of the word $w$. ... More
Sums of squares of the Littlewood-Richardson coefficients and GL(n)-harmonic polynomialsJun 02 2012Apr 22 2013We consider the example from invariant theory concerning the conjugation action of the general linear group on several copies of the $n \times n$ matrices, and examine a symmetric function which stably describes the Hilbert series for the invariant ring ... More
Thin Sequences and Their Role in $H^p$ Theory, Model Spaces, and Uniform AlgebrasDec 19 2013In this paper we revisit some facts about thin interpolating sequences in the unit disc from three perspectives: uniform algebras, model spaces, and $H^p$ spaces. We extend the notion of asymptotic interpolation to $H^p$ spaces, for $1 \leq p \leq \infty$, ... More
The group of invariants of an inner function with finite spectrumMar 30 2011This paper determines the group of continuous invariants corresponding to an inner function $ \Theta $ with finitely many singularities on the unit circle $T$; that is, the continuous mappings $g: T \to T$ such that $\Theta \circ g = \Theta $ on $\T$. ... More
On Collapsing Prefix Normal WordsMay 28 2019Prefix normal words are binary words in which each prefix has at least the same number of $\so$s as any factor of the same length. Firstly introduced by Fici and Lipt\'ak in 2011, the problem of determining the index of the prefix equivalence relation ... More
Numerical ranges of $C_0(N)$ contractionsSep 12 2010Dec 02 2010A conjecture of Halmos proved by Choi and Li states that the closure of the numerical range of a contraction on a Hilbert space is the intersection of the closure of the numerical ranges of all its unitary dilations. We show that for $C_0(N)$ contractions ... More
The $q$-analog of Kostant's partition function and the highest root of the classical Lie algebrasAug 31 2015Sep 18 2015Kostant's partition function counts the number of ways to represent a particular vector (weight) as a nonnegative integral sum of positive roots of a Lie algebra. For a given weight the $q$-analog of Kostant's partition function is a polynomial where ... More
From Glosten-Milgrom to the whole limit order book and applications to financial regulationFeb 27 2019We build an agent-based model for the order book with three types of market participants: informed trader, noise trader and competitive market makers. Using a Glosten-Milgrom like approach, we are able to deduce the whole limit order book (bid-ask spread ... More
Pervasive Algebras and Maximal SubalgebrasMay 05 2010A uniform algebra $A$ on its Shilov boundary $X$ is {\em maximal} if $A$ is not $C(X)$ and there is no uniform algebra properly contained between $A$ and $C(X)$. It is {\em essentially pervasive} if $A$ is dense in $C(F)$ whenever $F$ is a proper closed ... More
Inner functions and operator theoryMar 18 2015This tutorial paper presents a survey of results, both classical and new, linking inner functions and operator theory. Topics discussed include invariant subspaces, universal operators, Hankel and Toeplitz operators, model spaces, truncated Toeplitz operators, ... More
When do discretized data have a good behavior in functional nonparametric regression?Apr 28 2016Oct 06 2016In the context of nonparametric regression, we study condi- tions under which the consistency (and rates of convergence) of estimators built from discretely sampled curves can be derived from the consistency of estimators based on the unobserved whole ... More
From asymptotic properties of general point processes to the ranking of financial agentsJun 12 2019We propose a general non-linear order book model that is built from the individual behaviours of the agents. Our framework encompasses Markovian and Hawkes based models. Under mild assumptions, we prove original results on the ergodicity and diffusivity ... More
Regression calibration to correct correlated errors in outcome and exposureNov 26 2018Measurement error arises through a variety of mechanisms. A rich literature exists on the bias introduced by covariate measurement error and on methods of analysis to address this bias. By comparison, less attention has been given to errors in outcome ... More
The hidden circumgalactic mediumMar 11 2019The cycling of baryons in and out of galaxies is what ultimately drives galaxy formation and evolution. The circumgalactic medium (CGM) represents the interface between the interstellar medium and the cosmic web, hence its properties are directly shaped ... More
Science from an Ultra-Deep, High-Resolution Millimeter-Wave SurveyMar 08 2019Opening up a new window of millimeter-wave observations that span frequency bands in the range of 30 to 500 GHz, survey half the sky, and are both an order of magnitude deeper (about 0.5 uK-arcmin) and of higher-resolution (about 10 arcseconds) than currently ... More
The warm and dense Galaxy - tracing the formation of dense cloud structures out to the Galactic CenterMar 11 2019The past two decades have seen extensive surveys of the far-infrared to submillimeter continuum emission in the plane of our Galaxy. We line out prospects for the coming decade for corresponding molecular and atomic line surveys which are needed to fully ... More
Ionization driven molecular outflow in K3-50AJul 03 2013Whether high mass stars continue to accrete material beyond the formation of an HII region is still an open question. Ionized infall and outflow have been seen in some sources, but their ties to the surrounding molecular gas are not well constrained. ... More
Deep Learning How to Fit an Intravoxel Incoherent Motion Model to Diffusion-Weighted MRIFeb 28 2019Purpose: This prospective clinical study assesses the feasibility of training a deep neural network (DNN) for intravoxel incoherent motion (IVIM) model fitting to diffusion-weighted magnetic resonance imaging (DW-MRI) data and evaluates its performance. ... More
Cloud Disruption via Ionized Feedback: Tracing Pillar Dynamics in VulpeculaMar 24 2014The major physical processes responsible for shaping and sculpting pillars in the clouds surrounding massive stars (i.e. the `Pillars of Creation') are now being robustly incorporated into models quantifying the ionizing radiation from massive stars. ... More
An optical parsec-scale jet from a massive young star in the Large Magellanic CloudJan 24 2018Highly collimated parsec-scale jets, generally linked to the presence of an accretion disk, are a commonly observed phenomenon from revealed low-mass young stellar objects. In the past two decades, only a very few of these objects have been directly (or ... More
Characterizing the Adjacency Matrix of the Skeleton of the Strict Hypergraph of Layered Generalized CrownsOct 19 2014In 1974, Trotter provided a formula to compute the order dimension of the generalized crown $\mathbb{S}^k_n$. In 2014, Garcia and Silva defined a layering of generalized crowns and provided a formula for the order dimension of the $\ell$-layered generalized ... More
Aharonov-Bohm Oscillations in Photoluminescence from Charged Exciton in Quantum TubesAug 08 2007The oscillation of photoluminescence peak energies is observed in InAs quantum tubes depending on the magnetic flux through the tube. The oscillation is shown to be due to the Aharonov-Bohm effect of a charged exciton in a quantum tube. No quadratic shift ... More
Populations of models, Experimental Designs and coverage of parameter space by Latin Hypercube and Orthogonal SamplingFeb 19 2015In this paper we have used simulations to make a conjecture about the coverage of a $t$ dimensional subspace of a $d$ dimensional parameter space of size $n$ when performing $k$ trials of Latin Hypercube sampling. This takes the form $P(k,n,d,t)=1-e^{-k/n^{t-1}}$. ... More
On the classification problem for Poisson Point ProcessesDec 21 2015Jun 30 2016We study the binary classification problem for Poisson point processes, which are allowed to take values in a general metric space. The problem is tackled in two different ways: estimating nonparametricaly the intensity functions of the processes (and ... More
Screened-exchange density functional theory description of the electronic structure and phase stability of the chalcopyrite materials AgInSe$_2$ and AuInSe$_2$Sep 08 2015Mar 25 2016We present a systematic assessment of the structural properties, the electronic density of states, the charge densities, and the phase stabilities of AgInSe$_2$ and AuInSe$_2$ using screened exchange hybrid density functional theory, and compare their ... More
ALMA CO J=6-5 observations of IRAS16293-2422: Shocks and entrainmentDec 07 2012Observations of higher-excited transitions of abundant molecules such as CO are important for determining where energy in the form of shocks is fed back into the parental envelope of forming stars. The nearby prototypical and protobinary low-mass hot ... More
The Possibly Remnant Massive Outflow in G5.89-0.39: I - Observations and Initial MHD SimulationsMar 09 2006We have obtained maps of the large scale outflow associated with the UCHII regionG5.89-0.39 in CO and 13CO (J=3-2), SiO (J=8-7,J=5-4), SO2 (13(2,12)-13(1,13)) and H13CO+(J=4-3). From these maps we have been able to determine the mass (3.3 M_sun), momentum ... More
CO in HI Self-Absorbed Clouds in PerseusJun 27 2005We have observed 12CO J = 2-1 and J = 1-0, and 13CO J = 1-0 emission in two regions of HI Self-Absorption (HISA) in Perseus: a small, isolated HISA feature called the globule and a more extended HISA cloud called the complex. Using both Large Velocity ... More
The SiO outflow from IRAS 17233-3603 at high resolutionDec 18 2014Context: Jets and outflows are key ingredients in the formation of stars across the mass spectrum. In clustered regions, understanding powering sources and outflow components poses a significant problem. Aims: To understand the dynamics in the outflow(s) ... More
Evidential Value in ANOVA Results in Favor of FabricationApr 26 2013Some scientific publications are under suspicion of fabrication of data. Since humans are bad random number generators, there might be some evidential value in favor of fabrication in the statistical results as presented in such papers. In line with Uri ... More
Rotation of the Warm Molecular Gas Surrounding Ultracompact HII RegionsJul 24 2009We present molecular line and 1.4 mm continuum observations towards five massive star forming regions at arcsecond resolution using the Submillimeter Array (SMA). We find that the warm molecular gas surrounding each HII region (as traced by SO_2 and OCS) ... More
Sufficient dimension reduction for ordinal predictorsNov 17 2015The dimension reduction approaches commonly found in applications involving ordinal predictors are either extensions of unsupervised techniques such as principal component analysis or variable selection while modeling the regression under consideration. ... More
Character-Aware Decoder for Translation into Morphologically Rich LanguagesSep 06 2018Mar 28 2019Neural machine translation (NMT) systems operate primarily on words (or subwords), ignoring lower-level patterns of morphology. We present a character-aware decoder designed to capture such patterns when translating into morphologically rich languages. ... More
Computing upper bounds for optimal density of $(t,r)$ broadcasts on the infinite gridDec 01 2017The domination number of a finite graph $G$ with vertex set $V$ is the cardinality of the smallest set $S\subseteq V$ such that for every vertex $v\in V$ either $v\in S$ or $v$ is adjacent to a vertex in $S$. A set $S$ satisfying these conditions is called ... More
The adjoint representation of a Lie algebra and the support of Kostant's weight multiplicity formulaDec 30 2013Even though weight multiplicity formulas, such as Kostant's formula, exist their computational use is extremely cumbersome. In fact, even in cases when the multiplicity is well understood, the number of terms considered in Kostant's formula is factorial ... More
Counting fixed points and two-cycles of the singular map $x \mapsto x^{x^n}$ modulo powers of a primeSep 21 2016The "self-power" map $x \mapsto x^x$ modulo $m$ and its generalized form $x \mapsto x^{x^n}$ modulo $m$ are of considerable interest for both theoretical reasons and for potential applications to cryptography. In this paper, we use $p$-adic methods, primarily ... More
Character-Aware Decoder for Neural Machine TranslationSep 06 2018Sep 11 2018Standard neural machine translation (NMT) systems operate primarily on words, ignoring lower-level patterns of morphology. We present a character-aware decoder for NMT that can simultaneously work with both word-level and subword-level sequences which ... More
Early physics with top quarks at the LHCMay 21 2007May 30 2007The ATLAS and CMS experiments are now in their final installation phase and will be soon ready to study the physics of proton-proton collisions at the Large Hadron Collider. The LHC, by producing 2 $t\bar{t}$ events per second, will provide more than ... More
$τ$-tilting modules over one-point extensions by a projective moduleMay 20 2017Let $A$ be the one point extension of an algebra $B$ by a projective $B$-module. We prove that the extension of a given support $\tau$-tilting $B$-module is a support $\tau$-tilting $A$-module; and, conversely, the restriction of a given support $\tau$-tilting ... More
Reasoning about identifier spaces: How to make Chord correctOct 04 2016The Chord distributed hash table (DHT) is well-known and often used to implement peer-to-peer systems. Chord peers find other peers, and access their data, through a ring-shaped pointer structure in a large identifier space. Despite claims of proven correctness, ... More
Higgs Boson Searches at LEPMay 15 2003The results of the Higgs boson searches performed by the four LEP experiments at centre-of-mass energies between 189 GeV and 209 GeV corresponding to an integrated luminosity of 2461 pb$^{-1}$ are presented here. Searches have been performed for Higgs ... More
k-Spectra of c-Balanced WordsApr 19 2019A word $u$ is a scattered factor of $w$ if $u$ can be obtained from $w$ by deleting some of its letters. That is, there exist the (potentially empty) words $u_1,u_2,..., u_n$, and $v_0,v_1,..,v_n$ such that $u = u_1u_2...u_n$ and $w = v_0u_1v_1u_2v_2...u_nv_n$. ... More
Supervised dimension reduction for ordinal predictorsNov 17 2015Oct 12 2017In applications involving ordinal predictors, common approaches to reduce dimensionality are either extensions of unsupervised techniques such as principal component analysis, or variable selection procedures that rely on modeling the regression function. ... More
Optimal $(t,r)$ Broadcasts On the Infinite GridNov 29 2017Let $G=(V,E)$ be a graph and $t,r$ be positive integers. The signal that a vertex $v$ receives from a tower of signal strength $t$ located at vertex $T$ is defined as $sig(v,T)=max(t-dist(v,T),0)$, where $dist(v,T)$ denotes the distance between the vertices ... More
Orbits of non-elliptic disc automorphismsFeb 19 2010Dec 13 2011Motivated by the Invariant Subspace Problem, we describe explicitly the closed subspace $H^2$ generated by the limit points in the $H^2$ norm of the orbit of a thin Blaschke product $B$ under composition operators $C_\phi$ induced by non-elliptic automorphisms. ... More
When is the $q$-multiplicity of a weight a power of $q$?May 24 2019Berenshtein and Zelevinskii provided an exhaustive list of pairs of weights $(\lambda,\mu)$ of simple Lie algebras $\mathfrak{g}$ (up to Dynkin diagram isomorphism) for which the multiplicity of the weight $\mu$ in the representation of $\mathfrak{g}$ ... More
Local rewiring algorithms to increase clustering and grow a small worldAug 09 2016Aug 10 2016Many real-world networks have high clustering among vertices: vertices that share neighbors are often also directly connected to each other. A network's clustering can be a useful indicator of its connectedness and community structure. Algorithms for ... More
A nonlinear aggregation type classifierSep 04 2015Sep 09 2015We introduce a nonlinear aggregation type classifier for functional data defined on a separable and complete metric space. The new rule is built up from a collection of $M$ arbitrary training classifiers. If the classifiers are consistent, then so is ... More
Character-Aware Decoder for Translation into Morphologically Rich LanguagesSep 06 2018Jun 18 2019Neural machine translation (NMT) systems operate primarily on words (or sub-words), ignoring lower-level patterns of morphology. We present a character-aware decoder designed to capture such patterns when translating into morphologically rich languages. ... More
Sufficient dimension reduction for ordinal predictorsNov 17 2015Oct 06 2016In applications involving ordinal predictors, common approaches to reduce dimensional- ity are either extensions of unsupervised techniques such as principal component analysis, or variable selection procedures that rely on modeling the regression. We ... More
How to Make Chord CorrectFeb 23 2015Oct 06 2015The Chord distributed hash table (DHT) is well-known and frequently used to implement peer-to-peer systems. Chord peers find other peers, and access their data, through a ring-shaped pointer structure in a large identifier space. Despite claims of proven ... More
Chromospheric activity of Southern Stars from the Magellan Planet Search ProgramApr 16 2011I present chromospheric activity measurements of ~ 670 F, G, K and M main sequence stars in the Southern Hemisphere, from ~8000 archival high-resolution echelle spectra taken at Las Campanas Observatory since 2004. These stars were targets from the Old ... More