Results for "Simon J. Lock"
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Supervised multiway factorizationSep 11 2016We describe a probabilistic PARAFAC/CANDECOMP (CP) factorization for multiway (i.e., tensor) data that incorporates auxiliary covariates, SupCP. SupCP generalizes the supervised singular value decomposition (SupSVD) for vector-valued observations, to ... More Bayesian Consensus ClusteringFeb 28 2013The task of clustering a set of objects based on multiple sources of data arises in several modern applications. We propose an integrative statistical model that permits a separate clustering of the objects for each data source. These separate clusterings ... More A smörgåsbord of scalar-flat Kähler ALE surfacesOct 23 2014May 20 2016There are many known examples of scalar-flat K\"ahler ALE surfaces, all of which have group at infinity either cyclic or contained in ${\rm{SU}}(2)$. The main result in this paper shows that for any non-cyclic finite subgroup $\Gamma \subset {\rm{U}}(2)$ ... More Quotient singularities, eta invariants, and self-dual metricsJan 14 2015There are three main components to this article: (i) A formula for the eta invariant of the signature complex for any finite subgroup of ${\rm{SO}}(4)$ acting freely on $S^3$ is given. An application of this is a non-existence result for Ricci-flat ALE ... More Curved traversable wormholes in (3+1)-dimensional spacetimeJun 14 2013Dec 08 2013We present the general method of constructing curved traversable wormholes in (3+1)-d spacetime and proceed to thoroughly discuss the physics of a zero tidal force metric without cross-terms. The (3+1)-d solution is compared with the recently studied ... More Information requirements for enterprise systemsSep 24 2012In this paper, we discuss an approach to system requirements engineering, which is based on using models of the responsibilities assigned to agents in a multi-agency system of systems. The responsibility models serve as a basis for identifying the stakeholders ... More Binding Blocks: building the Universe one nucleus at the timeOct 07 2016We present a new teaching and outreach activity based around the construction of a three-dimensional chart of isotopes using LEGO$^{\copyright}$ bricks. The activity, \emph{Binding Blocks}, demonstrates nuclear and astrophysical processes through a seven-meter ... More Binding Blocks: building the Universe one nucleus at the timeOct 07 2016Oct 18 2016We present a new teaching and outreach activity based around the construction of a three-dimensional chart of isotopes using LEGO$^{\circledR}$ bricks. The activity, \emph{Binding Blocks}, demonstrates nuclear and astrophysical processes through a seven-meter ... More Rerandomization to improve covariate balance in experimentsJul 24 2012Randomized experiments are the "gold standard" for estimating causal effects, yet often in practice, chance imbalances exist in covariate distributions between treatment groups. If covariate data are available before units are exposed to treatments, these ... More An equivalence of scalar curvatures on Hermitian manifoldsMay 11 2015For a Kahler metric, the Riemannian scalar curvature is equal to twice the Chern scalar curvature. The question we address here is whether this equivalence can hold for a non-Kahler Hermitian metric. For such metrics, if they exist, the Chern scalar ... More Charge and orbital order in frustrated Pb3Mn7O15Jan 13 2012Mar 28 2012The candidate magnetoelectric Pb3Mn7O15 has a structure consisting of 1/3 filled Kagome layers linked by ribbons of edge-sharing octahedra in the stacking direction. Previous reports have indicated a complex hexagonal-orthorhombic structural transition ... More Anti-self-dual orbifolds with cyclic quotient singularitiesMay 17 2012An index theorem for the anti-self-dual deformation complex on anti-self-dual orbifolds with cyclic quotient singularities is proved. We present two applications of this theorem. The first is to compute the dimension of the deformation space of the Calderbank-Singer ... More Shared kernel Bayesian screeningNov 01 2013Feb 17 2016This article concerns testing for equality of distribution between groups. We focus on screening variables with shared distributional features such as common support, modes and patterns of skewness. We propose a Bayesian testing method using kernel mixtures, ... More Helicalised fractalsJun 19 2013Feb 14 2015We formulate the helicaliser, which replaces a given smooth curve by another curve that winds around it. In our analysis, we relate this formulation to the geometrical properties of the self-similar circular fractal (the discrete version of the curved ... More On the proportionality of Chern and Riemannian scalar curvaturesSep 01 2015Jun 21 2016On a Kahler manifold there is a clear connection between the complex geometry and underlying Riemannian geometry. In some ways, this can be used to characterize the Kahler condition. While such a link is not so obvious in the non-Kahler setting, one can ... More Classical Control of Large-Scale Quantum ComputersMay 20 2014The accelerated development of quantum technology has reached a pivotal point. Early in 2014, several results were published demonstrating that several experimental technologies are now accurate enough to satisfy the requirements of fault-tolerant, error ... More Two loop Kahler potential in beta-deformed N=4 SYM theoryMay 23 2008Aug 06 2008In N=2 superconformal field theories the Kahler potential is known to be tree level exact. The beta-deformation of N=4 SU(N) SYM reduces the amount of supersymmetry to N=1, allowing for non-trivial, superconformal loop corrections to the Kahler potential. ... More The potential for super-Nyquist asteroseismology with TESSAug 11 2015The perfect 30-min cadence of the full-frame images from the Transiting Exoplanet Survey Satellite (TESS) will impose a hard Nyquist limit of 24 d$^{-1}$ ($\approx 278$ $\mu$Hz). This will be problematic for asteroseismology of stars with oscillation ... More Coevality in Young Eclipsing BinariesApr 29 2017The ages of the components in very short period pre-main sequence (PMS) binaries are essential to an understanding of their formation. We considered a sample of 7 PMS eclipsing binaries (EBs) with ages 1 to 6.3 MY and component masses 0.2 to 1.4 Msun ... More Performing Quantum Computing Experiments in the CloudMay 18 2016Sep 01 2016Quantum computing technology has reached a second renaissance in the past five years. Increased interest from both the private and public sector combined with extraordinary theoretical and experimental progress has solidified this technology as a major ... More Balancing Covariates via Propensity Score WeightingSep 23 2016Covariate balance is crucial for unconfounded descriptive or causal comparisons. However, lack of balance is common in observational studies. This article considers weighting strategies for balancing covariates. We define a general class of weights---the ... More Balancing Covariates via Propensity Score WeightingApr 07 2014Nov 15 2016Covariate balance is crucial for unconfounded descriptive or causal comparisons. However, lack of balance is common in observational studies. This article considers weighting strategies for balancing covariates. We define a general class of weights---the ... More Balancing Covariates via Propensity Score WeightingSep 23 2016Sep 29 2016Covariate balance is crucial for unconfounded descriptive or causal comparisons. However, lack of balance is common in observational studies. This article considers weighting strategies for balancing covariates. We define a general class of weights---the ... More Network Extreme Eigenvalue - from Multimodal to Scale-free NetworkJul 13 2011Dec 22 2011The extreme eigenvalues of adjacency matrices are important indicators on the influences of topological structures to collective dynamical behavior of complex networks. Recent findings on the ensemble averageability of the extreme eigenvalue further authenticate ... More Superdirected Beam of the Surface Spin WaveNov 29 2016Visualized diffraction patterns of the surface spin wave excited by arbitrarily oriented linear transducer in tangentially magnetized ferrite film are investigated experimentally in the plane of ferrite film for the case where the transducer length D ... More D-modules on rigid analytic spaces II: Kashiwara's equivalenceFeb 04 2015We prove that the category of co-admissible D-cap-modules on a smooth rigid analytic space supported on a closed smooth subvariety is naturally equivalent to the category of co-admissible D-cap-modules on the subvariety, and use this result to construct ... More Spatiospectral concentration of vector fields on a sphereJun 13 2013We construct spherical vector bases that are bandlimited and spatially concentrated, or, alternatively, spacelimited and spectrally concentrated, suitable for the analysis and representation of real-valued vector fields on the surface of the unit sphere, ... More Fixed Block Compression Boosting in FM-IndexesApr 19 2011A compressed full-text self-index occupies space close to that of the compressed text and simultaneously allows fast pattern matching and random access to the underlying text. Among the best compressed self-indexes, in theory and in practice, are several ... More Gaia's view of the $λ$ Boo star puzzleDec 05 2016The evolutionary status of the chemically peculiar class of $\lambda$ Boo stars has been intensely debated. It is now agreed that the $\lambda$ Boo phenomenon affects A stars of all ages, from star formation to the terminal age main sequence, but the ... More Spectral Anlysis on Explosive PercolationJan 03 2013We study the spectral properties of the process of explosive percolation. In particular, we explore how the maximum eigenvalue of the adjacency matrix of a network which governs the spreading efficiency evolves as the density of connection increases. ... More Further Wolf-Rayet stars in the starburst cluster Westerlund 1Mar 14 2005Mar 21 2005We present new low and intermediate-resolution spectroscopic observations of the Wolf Rayet (WR) star population in the massive starburst cluster Westerlund 1. Finding charts are presented for five new WRs - four WNL and one WCL - raising the current ... More Scalable Similarity Search for Molecular DescriptorsNov 30 2016Similarity search over chemical compound databases is a fundamental task in the discovery and design of novel drug-like molecules. Such databases often encode molecules as non-negative integer vectors, called molecular descriptors, which represent rich ... More Moebius energy of thick knotsAug 30 2001The Moebius energy of a knot is an energy functional for smooth curves based on an idea of self-repelling. If a knot has a thick tubular neighborhood, we would intuitively expect the energy to be low. In this paper, we give explicit bounds for energy ... More Disentangling Mass and Mixing HierarchiesJun 30 2015Oct 23 2015We present a fully perturbative mechanism that naturally generates mass hierarchies for the Standard Model (SM) fermions in a flavor-blind sector. The dynamics generating the mass hierarchies can therefore be independent from the source of flavor violation, ... More Range Predecessor and Lempel-Ziv ParsingJul 25 2015The Lempel-Ziv parsing of a string (LZ77 for short) is one of the most important and widely-used algorithmic tools in data compression and string processing. We show that the Lempel-Ziv parsing of a string of length $n$ on an alphabet of size $\sigma$ ... More Entanglement of Formation for Gaussian StatesAug 12 2008The entanglement of formation (EOF) is computed for arbitrary two-mode Gaussian states. Apart from a conjecture, our analysis rests on two main ingredients. The first is a four-parameter canonical form we develop for the covariance matrix, one of these ... More Behavioural PrototypesSep 03 2016We sketch a simple language of concurrent objects which explores the design space between type systems and continuous testing. In our language, programs are collections of communicating automata checked automatically for multiparty compatibility. This ... More An introduction to Fault-tolerant Quantum ComputingAug 15 2015In this paper we provide a basic introduction of the core ideas and theories surrounding fault-tolerant quantum computation. These concepts underly the theoretical framework of large-scale quantum computation and communications and are the driving force ... More Searching and Indexing Genomic Databases via KernelizationDec 04 2014The rapid advance of DNA sequencing technologies has yielded databases of thousands of genomes. To search and index these databases effectively, it is important that we take advantage of the similarity between those genomes. Several authors have recently ... More Probing of quantum dissipative chaos by purityMay 22 2013Sep 06 2013In this paper, the purity of quantum states is applied to probe chaotic dissipative dynamics. To achieve this goal, a comparative analysis of regular and chaotic regimes of nonlinear dissipative oscillator (NDO) are performed on the base of excitation ... More Balancing Covariates via Propensity Score WeightingApr 07 2014Jan 27 2015Covariate balance is crucial for an unconfounded descriptive or causal comparison. However, lack of balance is common in observational studies. This article considers weighting strategies for balancing covariates. We define a general class of weights-the ... More Discriminating sample groups with multi-way dataJun 26 2016High-dimensional linear classifiers, such as the support vector machine (SVM) and distance weighted discrimination (DWD), are commonly used in biomedical research to distinguish groups of subjects based on a large number of features. However, their use ... More The Abelian Manna model on two fractal latticesJun 30 2010We analyze the avalanche size distribution of the Abelian Manna model on two different fractal lattices with the same dimension d_g=ln(3)/ln(2), with the aim to probe for scaling behavior and to study the systematic dependence of the critical exponents ... More Crossed products by twisted partial actions and graded algebrasJun 24 2008For a twisted partial action \Theta of a group G on an (associative non-necessarily unital) algebra A over a commutative unital ring k, the crossed product A X_\Theta G is proved to be associative. Given a G-graded k-algebra B = \oplus_{g\in G}\B_g with ... More Vortex Chains in Anisotropic SuperconductorsJul 01 2005High-T_c superconductors in small magnetic fields directed away from the crystal symmetry axes have been found to exhibit inhomogeneous chains of flux lines (vortices), in contrast to the usual regular triangular flux-line lattice. We review the experimental ... More The Clustering of Faint Galaxies and the Evolution of $ξ$(r)May 11 1996The two-point angular correlation function, $\w$, is constructed from a catalog of 13,000 objects in 24 fields distributed over an area of 4 deg$^2$ and complete to a limit of $R = 23.5$. The amplitude and slope of our correlation function on arcminute ... More Extending the Reach of QKD Using RelaysMar 03 2012One of the obstacles to deployment of QKD solutions has been the distance limitation. Solutions using relays have been proposed but these rely on link-by-link key establishment. We present a new technique to extend the distance of a quantum key distribution ... More Mass Dependence of Quantum Energy Inequality BoundsFeb 21 2007In a recent paper [J. Math. Phys. 47 082303 (2006)], Quantum Energy Inequalities were used to place simple geometrical bounds on the energy densities of quantum fields in Minkowskian spacetime regions. Here, we refine this analysis for massive fields, ... More Spherical Slepian functions and the polar gap in geodesyMar 11 2006The estimation of potential fields such as the gravitational or magnetic potential at the surface of a spherical planet from noisy observations taken at an altitude over an incomplete portion of the globe is a classic example of an ill-posed inverse problem. ... More Local and Distributed Quantum ComputationMay 23 2016Experimental groups are now fabricating quantum processors powerful enough to execute small instances of quantum algorithms and definitively demonstrate quantum error correction that extends the lifetime of quantum data, adding urgency to architectural ... More Operator-sum Representation for Bosonic Gaussian ChannelsDec 20 2010Operator-sum or Kraus representations for single-mode Bosonic Gaussian channels are developed, and several of their consequences explored. Kraus operators are employed to bring out the manner in which the unphysical matrix transposition map when accompanied ... More Gorenstein rings call the tuneJul 16 2004Hochster's Monomial Conjecture and Canonical Element Conjecture date back some thirty resp. twenty years. They concern all noetherian commutative local rings, and were proved by their originator right away in equal characteristic. Thanks to recent important ... More A bridge to lower overhead quantum computationSep 04 2012Apr 09 2013Two primary challenges stand in the way of practical large-scale quantum computation, namely achieving sufficiently low error rate quantum gates and implementing interesting quantum algorithms with a physically reasonable number of qubits. In this work ... More Systemization of Pluggable Transports for Censorship ResistanceDec 23 2014Jul 29 2016An increasing number of countries implement Internet censorship at different scales and for a variety of reasons. In particular, the link between the censored client and entry point to the uncensored network is a frequent target of censorship due to the ... More Diphotons from an Electroweak Triplet-SingletMar 29 2016The neutral component of a real pseudoscalar electroweak (EW) triplet can produce a diphoton excess at 750 GeV, if it is somewhat mixed with an EW singlet pseudoscalar. This triplet-singlet mixing allows for greater freedom in the diboson branching ratios ... More String Inference from the LCP ArrayJun 14 2016The suffix array is often augmented with the longest common prefix (LCP) array which is, in essence, a representation of the suffix tree shape. We consider the problem of inferring a string from an LCP array, i.e., determining whether a given array of ... More