Results for "Thomas Meier"

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The Complexity of Reasoning for Fragments of Autoepistemic LogicJun 01 2010Autoepistemic logic extends propositional logic by the modal operator L. A formula that is preceded by an L is said to be "believed". The logic was introduced by Moore 1985 for modeling an ideally rational agent's behavior and reasoning about his own ... More
The Complexity of Monotone Hybrid Logics over Linear Frames and the Natural NumbersApr 05 2012Jun 12 2012Hybrid logic with binders is an expressive specification language. Its satisfiability problem is undecidable in general. If frames are restricted to N or general linear orders, then satisfiability is known to be decidable, but of non-elementary complexity. ... More
Generalized Satisfiability for the Description Logic ALCMar 04 2011The standard reasoning problem, concept satisfiability, in the basic description logic ALC is PSPACE-complete, and it is EXPTIME-complete in the presence of unrestricted axioms. Several fragments of ALC, notably logics in the FL, EL, and DL-Lite families, ... More
The Complexity of Satisfiability for Sub-Boolean Fragments of ALCJan 24 2010Mar 29 2010The standard reasoning problem, concept satisfiability, in the basic description logic ALC is PSPACE-complete, and it is EXPTIME-complete in the presence of unrestricted axioms. Several fragments of ALC, notably logics in the FL, EL, and DL-Lite family, ... More
Macro pose based non-invasive thermal comfort perception for energy efficiencyNov 12 2018Dec 20 2018Individual thermal comfort perception gives important feedback signals for energy efficient control of smart buildings. However, there is no effective method to measure real-time thermal comfort status of individual occupant until now. For overcoming ... More
Topological modular forms with level structure: decompositions and dualityJun 18 2018Topological modular forms with level structure were introduced in full generality by Hill and Lawson. We will show that these decompose additively in many cases into a few simple pieces and give an application to equivariant $TMF$. Furthermore, we show ... More
Finitely additive beliefs and universal type spacesFeb 28 2006The probabilistic type spaces in the sense of Harsanyi [Management Sci. 14 (1967/68) 159--182, 320--334, 486--502] are the prevalent models used to describe interactive uncertainty. In this paper we examine the existence of a universal type space when ... More
Thermodynamics and Spin Tunneling Dynamics in Ferric Wheels with Excess SpinJul 02 2001We study theoretically the thermodynamic properties and spin dynamics of a class of magnetic rings closely related to ferric wheels, antiferromagnetic ring systems, in which one of the Fe (III) ions has been replaced by a dopant ion to create an excess ... More
A Probabilistic Representation for Dynamic Movement PrimitivesDec 18 2016Dynamic Movement Primitives have successfully been used to realize imitation learning, trial-and-error learning, reinforce- ment learning, movement recognition and segmentation and control. Because of this they have become a popular represen- tation for ... More
An Alternative Between Non-unique and Negative Yamabe Solutions to the Conformal Formulation of the Einstein Constraint EquationsJun 05 2013The conformal method has been effective for parametrizing solutions to the Einstein constraint equations on closed 3-manifolds. However, it is still not well-understood; for example, existence of solutions to the conformal equations for zero or negative ... More
Generalized Solutions to Semilinear Elliptic PDE with Applications to the Lichnerowicz EquationDec 01 2011Mar 18 2013In this article we investigate the existence of a solution to a semilinear, elliptic, partial differential equation with distributional coefficients and data. The problem we consider is a generalization of the Lichnerowicz equation that one encounters ... More
Fibrancy of Partial Model CategoriesAug 12 2014We investigate fibrancy conditions in the Thomason model structure on the category of small categories. In particular, we show that the category of weak equivalences of a partial model category is fibrant. Furthermore, we describe connections to calculi ... More
Analysis of a three flavor neutrino oscillation fit to recent Super-Kamiokande dataOct 07 1999Nov 03 1999We have analyzed the most recent available Super-Kamiokande data in a three flavor neutrino oscillation model. We have here neglected possible matter effects and performed a fit to atmospheric and solar Super-Kamiokande data. We have investigated a large ... More
The Association of Jet Production with Geometrically Thick Accretion Flows and Black Hole RotationOct 12 2000A model is presented in which the strongest radio-emitting jet outflows are produced in black hole systems when the accretion is a geometrically thick ($H/R \sim 1$) inflow ({\it e.g.}, ADAF, CDAF) {\em and} if the black hole is rotating. For galactic ... More
Grand Unification of AGN and the Accretion and Spin ParadigmsAug 26 1999While attempts to unify certain classes of AGN using orientation and environmental effects have been successful, it is widely recognized that intrinsic properties of the accreting black hole system also must play a role in determining the appearance of ... More
Sticking behavior and transformation of tin droplets on silicon wafers and multilayer-coated mirrorsAug 11 2019Silicon wafer and multilayer-coated mirror samples were exposed to impact of drops of molten tin to examine the adhesion behavior and cleaning possibilities. The sticking of tin droplets to horizontal substrates was examined for different surface conditions ... More
Smoothing $\ell_1$-penalized estimators for high-dimensional time-course dataDec 11 2007When a series of (related) linear models has to be estimated it is often appropriate to combine the different data-sets to construct more efficient estimators. We use $\ell_1$-penalized estimators like the Lasso or the Adaptive Lasso which can simultaneously ... More
Neuromorphic Learning towards Nano Second PrecisionSep 17 2013Sep 18 2013Temporal coding is one approach to representing information in spiking neural networks. An example of its application is the location of sounds by barn owls that requires especially precise temporal coding. Dependent upon the azimuthal angle, the arrival ... More
The Complexity of Propositional ImplicationNov 06 2008Aug 12 2009The question whether a set of formulae G implies a formula f is fundamental. The present paper studies the complexity of the above implication problem for propositional formulae that are built from a systematically restricted set of Boolean connectives. ... More
Chapter 34 - Every Moment Counts: Synchrophasors for Distribution Networks with Variable ResourcesAug 08 2014Historically, with mostly radial power distribution and one-way power flow, it was only necessary to evaluate the envelope of design conditions, e.g., peak loads or fault currents, rather than continually observe the operating state. But the growth of ... More
Improving Resolution of Solid State NMR in Dense Molecular HydrogenAug 03 2019Recent advancements in radio-frequency resonator designs have led to the implementation of nuclear magnetic resonance in diamond anvil cells (DACs) at pressures well above 100 GPa. However, a relatively low resolution and the absence of decoupling sequences ... More
Dynamics of short time--scale energy relaxation of optical excitations due to electron--electron scattering in the presence of arbitrary disorderNov 11 2002Apr 11 2003A non--equilibrium occupation distribution relaxes towards the Fermi--Dirac distribution due to electron--electron scattering even in finite Fermi systems. The dynamic evolution of this thermalization process assumed to result from an optical excitation ... More
The Complexity of Reasoning for Fragments of Default LogicAug 28 2008Aug 23 2010Default logic was introduced by Reiter in 1980. In 1992, Gottlob classified the complexity of the extension existence problem for propositional default logic as $\SigmaPtwo$-complete, and the complexity of the credulous and skeptical reasoning problem ... More
On the Parameterized Complexity of Default Logic and Autoepistemic LogicOct 04 2011Oct 06 2011We investigate the application of Courcelle's Theorem and the logspace version of Elberfeld etal. in the context of the implication problem for propositional sets of formulae, the extension existence problem for default logic, as well as the expansion ... More
Observation of Nuclear Quantum Effects and Hydrogen Bond Symmetrisation in High Pressure IceMar 19 2018Hydrogen bond symmetrisations in H-bonded systems triggered by pressure induced nuclear quantum effects (NQEs) is a long-known concept1 but experimental evidences in high-pressure ices have remained elusive with conventional methods2,3. Theoretical works ... More
Neuromorphic Hardware learns to learnMar 15 2019Mar 18 2019Hyperparameters and learning algorithms for neuromorphic hardware are usually chosen by hand. In contrast, the hyperparameters and learning algorithms of networks of neurons in the brain, which they aim to emulate, have been optimized through extensive ... More
SIMMUNE, a tool for simulating and analyzing immune system behaviorMar 28 1999We present a new approach to the simulation and analysis of immune system behavior. The simulations that can be done with our software package called SIMMUNE are based on immunological data that describe the behavior of immune system agents (cells, molecules) ... More
The Complexity of Satisfiability for Fragments of Hybrid Logic -- Part IJun 08 2009The satisfiability problem of hybrid logics with the downarrow binder is known to be undecidable. This initiated a research program on decidable and tractable fragments. In this paper, we investigate the effect of restricting the propositional part of ... More
NMR close to Mega-Bar PressuresMar 14 2018The past 15 years have seen an astonishing increase in Nuclear Magnetic Resonance (NMR) sensitivity and accessible pressure range in high-pressure NMR experiments, owing to a series of new developments of NMR spectroscopy applied to the diamond anvil ... More
Model Checking CTL is Almost Always Inherently SequentialMar 25 2011Nov 15 2011The model checking problem for CTL is known to be P-complete (Clarke, Emerson, and Sistla (1986), see Schnoebelen (2002)). We consider fragments of CTL obtained by restricting the use of temporal modalities or the use of negations---restrictions already ... More
Anisotropic Excitons and their Contributions to Shift Current Transients in Bulk GaAsAug 28 2017Shift current transient are obtained for near band gap excitation of bulk GaAs by numerical solutions of the semiconductor Bloch equations in a basis obtained from a 14 band k.p model of the band structure. This approach provides a transparent description ... More
Local Gaussian RegressionFeb 04 2014Locally weighted regression was created as a nonparametric learning method that is computationally efficient, can learn from very large amounts of data and add data incrementally. An interesting feature of locally weighted regression is that it can work ... More
Wireless Interference Identification with Convolutional Neural NetworksMar 02 2017The steadily growing use of license-free frequency bands requires reliable coexistence management for deterministic medium utilization. For interference mitigation, proper wireless interference identification (WII) is essential. In this work we propose ... More
Orbit equivalence of graphs and isomorphism of graph groupoidsOct 31 2016Jan 24 2017We show that the groupoids of two directed graphs are isomorphic if and only if the two graphs are orbit equivalent by an orbit equivalence that preserves isolated eventually periodic points. We also give a complete description of the (topological) isolated ... More
Uniform trace formulae for SU(2) and SO(3) symmetry breakingJul 30 1998Nov 09 1998We develop uniform approximations for the trace formula for non-integrable systems in which SU(2) symmetry is broken by a non-linear term of the Hamiltonian. As specific examples, we investigate H\'enon-Heiles type potentials. Our formalism can also be ... More
Combinatorial conditions that imply word-hyperbolicity for 3-manifoldsJan 07 2003Thurston conjectured that a closed triangulated 3-manifold in which every edge has degree 5 or 6, and no two edges of degree 5 lie in a common 2-cell, has word-hyperbolic fundamental group. We establish Thurston's conjecture by proving that such a manifold ... More
A tale of clusters: No resolvable periodicity in the terrestrial impact cratering recordJan 31 2017Rampino & Caldeira (2015) carry out a circular spectral analysis (CSA) of the terrestrial impact cratering record over the past 260 million years (Ma), and suggest a ~26 Ma periodicity of impact events. For some of the impacts in that analysis, new accurate ... More
A Whitehead theorem for periodic homotopy groupsNov 09 2018We show that $v_n$-periodic homotopy groups detect homotopy equivalences between simply-connected finite CW-complexes.
Elementary solution to the time-independent quantum navigation problemSep 23 2014A quantum navigation problem concerns the identification of a time-optimal Hamiltonian that realises a required quantum process or task, under the influence of a prevailing `background' Hamiltonian that cannot be manipulated. When the task is to transform ... More
Approximating Real-Time Recurrent Learning with Random Kronecker FactorsMay 28 2018Dec 05 2018Despite all the impressive advances of recurrent neural networks, sequential data is still in need of better modelling. Truncated backpropagation through time (TBPTT), the learning algorithm most widely used in practice, suffers from the truncation bias, ... More
Is a 4-bit synaptic weight resolution enough? - Constraints on enabling spike-timing dependent plasticity in neuromorphic hardwareJan 30 2012Nov 28 2014Large-scale neuromorphic hardware systems typically bear the trade-off between detail level and required chip resources. Especially when implementing spike-timing-dependent plasticity, reduction in resources leads to limitations as compared to floating ... More
Optically induced coherent intra-band dynamics in disordered semiconductorsNov 21 2001On the basis of a tight-binding model for a strongly disordered semiconductor with correlated conduction- and valence band disorder a new coherent dynamical intra-band effect is analyzed. For systems that are excited by two, specially designed ultrashort ... More
Microscopic modeling of photoluminescence of strongly disordered semiconductorsMay 09 2005Feb 07 2006A microscopic theory for the luminescence of ordered semiconductors is modified to describe photoluminescence of strongly disordered semiconductors. The approach includes both diagonal disorder and the many-body Coulomb interaction. As a case study, the ... More
Generalized Seismic Phase Detection with Deep LearningMay 03 2018Jan 11 2019To optimally monitor earthquake-generating processes, seismologists have sought to lower detection sensitivities ever since instrumental seismic networks were started about a century ago. Recently, it has become possible to search continuous waveform ... More
Propagation of Coulomb-correlated electron-hole pairs in semiconductors with correlated and anticorrelated disorderFeb 28 2000Local ultrafast optical excitation of electron-hole pairs in disordered semiconductors provides the possibility to observe experimentally interaction-assisted propagation of correlated quantum particles in a disordered environment. In addition to the ... More
Magnetic Flux Tailoring through Lenz Lenses in Toroidal Diamond Indenter Cells: A New Pathway to High Pressure Nuclear Magnetic ResonanceMay 24 2017A new pathway to nuclear magnetic resonance spectroscopy in high pressure diamond anvil cells is introduced, using inductively coupled broadband passive electro-magnetic lenses to locally amplify the magnetic flux at the isolated sample, leading to an ... More
Signatures of Many-Particle Correlations in Two-Dimensional Fourier-Transform Spectra of Semiconductor NanostructuresFeb 05 2007On the basis of a microscopic theory, the signatures of many-particle correlations in Two-Dimensional Fourier-Transform Spectra (2D-FTS) of semiconductor nanostructures are identified and compared to experimental data. Spectra in the photon energy range ... More
Dynamics of Coulomb-correlated electron-hole pairs in disordered semiconductor nanowiresNov 23 2001The dynamics of optically generated electron-hole pairs is investigated in a disordered semiconductor nanowire. The particle pairs are generated by short laser pulses and their dynamics is followed using the Heisenberg equation of motion. Is is shown ... More
The effect of heterogeneity on decorrelation mechanisms in spiking neural networks: a neuromorphic-hardware studyNov 28 2014Jun 09 2016High-level brain function such as memory, classification or reasoning can be realized by means of recurrent networks of simplified model neurons. Analog neuromorphic hardware constitutes a fast and energy efficient substrate for the implementation of ... More
Joule heating in nanowiresDec 20 2010Aug 30 2011We study the effect of Joule heating from electric currents flowing through ferromagnetic nanowires on the temperature of the nanowires and on the temperature of the substrate on which the nanowires are grown. The spatial current density distribution, ... More
Interacting electrons in a one-dimensional random array of scatterers - A Quantum Dynamics and Monte-Carlo studyMar 28 2002The quantum dynamics of an ensemble of interacting electrons in an array of random scatterers is treated using a new numerical approach for the calculation of average values of quantum operators and time correlation functions in the Wigner representation. ... More
PhaseLink: A Deep Learning Approach to Seismic Phase AssociationSep 08 2018Jan 10 2019Seismic phase association is a fundamental task in seismology that pertains to linking together phase detections on different sensors that originate from a common earthquake. It is widely employed to detect earthquakes on permanent and temporary seismic ... More
Generalized Complexity of ALC SubsumptionMay 03 2012The subsumption problem with respect to terminologies in the description logic ALC is EXPTIME-complete. We investigate the computational complexity of fragments of this problem by means of allowed Boolean operators. Hereto we make use of the notion of ... More
Topological modular forms with level structure: decompositions and dualityJun 18 2018Jul 11 2019Topological modular forms with level structure were introduced in full generality by Hill and Lawson. We will show that these decompose additively in many cases into a few simple pieces and give an application to equivariant $TMF$. Furthermore, we show ... More
Vector Bundles on the Moduli Stack of Elliptic CurvesJul 31 2013Apr 20 2015We study vector bundles on the moduli stack of elliptic curves over a local ring R. If R is a field or a discrete valuation ring of (residue) characteristic not 2 or 3, all these vector bundles are sums of line bundles. For R the 3-local integers, we ... More
Predicting GradesAug 16 2015Mar 18 2016To increase efficacy in traditional classroom courses as well as in Massive Open Online Courses (MOOCs), automated systems supporting the instructor are needed. One important problem is to automatically detect students that are going to do poorly in a ... More
Connectivity at Infinity for the Braid Group of a Complete Bipartite GraphAug 01 2019The graph braid group of a complete bipartite graph is the fundamental group of a configuration space of points on the graph, which is a CAT(0) cube complex. We combine an analysis of the topology of links of vertices in this complex, the description ... More
High-dimensional additive modelingJun 25 2008Nov 18 2009We propose a new sparsity-smoothness penalty for high-dimensional generalized additive models. The combination of sparsity and smoothness is crucial for mathematical theory as well as performance for finite-sample data. We present a computationally efficient ... More
Distinguishing topologically and smoothly doubly slice knotsJan 06 2014Nov 03 2014We construct an infinite family of smoothly slice knots that we prove are topologically doubly slice. Using the correction terms coming from Heegaard Floer homology, we show that none of these knots is smoothly doubly slice. We use these knots to show ... More
Spectral Sequences in String TopologyJan 27 2010Aug 08 2015In this paper, we investigate the behaviour of the Serre spectral sequence with respect to the algebraic structures of string topology in generalized homology theories, specificially with the Chas-Sullivan product and the corresponding coproduct and module ... More
Tunneling induced electron transfer between separated protonsOct 18 2017We study electron transfer between two separated nuclei using local control theory. By conditioning the algorithm in a symmetric system formed by two protons, one can favored slow transfer processes, where tunneling is the main mechanism, achieving transfer ... More
Least angle and $\ell_1$ penalized regression: A reviewFeb 07 2008May 21 2008Least Angle Regression is a promising technique for variable selection applications, offering a nice alternative to stepwise regression. It provides an explanation for the similar behavior of LASSO ($\ell_1$-penalized regression) and forward stagewise ... More
Co-universal algebras associated to product systems, and gauge-invariant uniqueness theoremsJun 26 2009Sep 26 2009Let X be a product system over a quasi-lattice ordered group. Under mild hypotheses, we associate to X a C*-algebra which is co-universal for injective Nica covariant Toeplitz representations of X which preserve the gauge coaction. Under appropriate amenability ... More
(Topological) modular forms with level structures: decompositions and dualitySep 29 2016The present article studies decompositions of vector bundles on the moduli stack of elliptic curves that are pushforwards of vector bundles on moduli of elliptic curves with level structure. These imply decomposition results for rings of modular forms ... More
Magnetically-Dominated Accretion Flows (MDAFs) and Jet Production in the Low/Hard STateApr 22 2005In this paper I propose that the inner part of a black hole accretion inflow ($< 100 r_{g}$) may enter a magnetically-dominated, magnetosphere-like phase in which the strong, well-ordered fields play a more important role than weak, turbulent fields. ... More
Small Seifert fibered surgery on hyperbolic pretzel knotsOct 29 2012Jul 23 2013We complete the classification of hyperbolic pretzel knots admitting Seifert fibered surgeries. This is the final step in understanding all exceptional surgeries on hyperbolic pretzel knots. We also present results toward similar classifications for non-pretzel ... More
Fibration Categories are Fibrant Relative CategoriesMar 06 2015Apr 20 2015A relative category is a category with a chosen class of weak equivalences. Barwick and Kan produced a model structure on the category of all relative categories, which is Quillen equivalent to the Joyal model structure on simplicial sets and the Rezk ... More
(Topological) modular forms with level structures: decompositions and dualitySep 29 2016Feb 20 2017The present article studies decompositions of vector bundles on the moduli stack of elliptic curves that are pushforwards of vector bundles on moduli of elliptic curves with level structure. These imply decomposition results for rings of modular forms ... More
Microscopic analysis of the coherent optical generation and the decay of charge and spin currents in semiconductor heterostructuresFeb 23 2005The coherent optical injection and temporal decay of spin and charge currents in semiconductor heterostructures is described microscopically, including excitonic effects, carrier LO-phonon and carrier-carrier scattering, as well as nonperturbative light-field-induced ... More
Geometrically exact beam elements and smooth contact schemes for the modeling of fiber-based materials and structuresNov 19 2016Recently, the authors have proposed a novel all-angle beam contact (ABC) formulation that combines the advantages of existing point and line contact models in a variationally consistent manner. However, the ABC formulation has so far only been applied ... More
A Computational Model for Molecular Interactions Between Curved Slender Fibers Undergoing Large 3D Deformations With a Focus on Electrostatic, van der Waals and Repulsive Steric ForcesJul 30 2019Jul 31 2019This contribution proposes the first 3D beam-to-beam interaction model for molecular interactions between curved slender fibers undergoing large deformations. While the general model is not restricted to a specific beam formulation, in the present work ... More
Investigation of the Peeling and Pull-off Behavior of Adhesive Elastic Fibers via a Novel Computational Beam Interaction ModelJul 30 2019Jul 31 2019This article studies the fundamental problem of separating two adhesive elastic fibers based on numerical simulation employing a recently developed finite element model for molecular interactions between curved slender fibers. Specifically, it covers ... More
Object Recognition with Multi-Scale Pyramidal Pooling NetworksJul 07 2012We present a Multi-Scale Pyramidal Pooling Network, featuring a novel pyramidal pooling layer at multiple scales and a novel encoding layer. Thanks to the former the network does not require all images of a given classification task to be of equal size. ... More
Physics Performance with the CMS Pixel DetectorDec 17 2014A large fraction of the results produced by the LHC experiments during the first run were made possible by precision vertexing detectors. The all-silicon tracking detector of the CMS experiment uses a pixel detector to do vertexing. This conference report ... More
First Alignment of the Complete CMS TrackerMar 12 2010This conference proceeding presents the first results of the full CMS Tracker alignment based on several million reconstructed tracks from the cosmic data taken during the commissioning runs with the detector in its final position and magnetic field present. ... More
A note on cabled slice knots and reducible surgeriesJul 16 2015We consider the question of when a slice knot admits a reducible Dehn surgery. By analyzing the correction terms associated to such a surgery, we show that slice knots cannot admit surgeries with more than two summands. We also give a necessary Heegaard ... More
High spatial coherence in multiphoton-photoemitted electron beamsNov 15 2018Nanometer-sharp metallic tips are known to be excellent electron emitters. They are used in highest-resolution electron microscopes in cold field emission mode to generate the most coherent electron beam in continuous-wave operation. For time-resolved ... More
A hit-and-run Giant Impact scenarioJul 22 2012The formation of the Moon from the debris of a slow and grazing giant impact of a Mars-sized impactor on the proto-Earth (Cameron & Ward 1976, Canup & Asphaug 2001) is widely accepted today. We present an alternative scenario with a hit-and-run collision ... More
Learning Sensor Feedback Models from Demonstrations via Phase-Modulated Neural NetworksOct 24 2017Mar 15 2018In order to robustly execute a task under environmental uncertainty, a robot needs to be able to reactively adapt to changes arising in its environment. The environment changes are usually reflected in deviation from expected sensory traces. These deviations ... More
Learning Feedback Terms for Reactive Planning and ControlOct 11 2016Mar 03 2017With the advancement of robotics, machine learning, and machine perception, increasingly more robots will enter human environments to assist with daily tasks. However, dynamically-changing human environments requires reactive motion plans. Reactivity ... More
Resource Allocation for a Wireless Coexistence Management System Based on Reinforcement LearningMay 24 2018In industrial environments, an increasing amount of wireless devices are used, which utilize license-free bands. As a consequence of these mutual interferences of wireless systems might decrease the state of coexistence. Therefore, a central coexistence ... More
Step size of the rotary proton motor in single FoF1-ATP synthase from a thermoalkaliphilic bacterium by DCO-ALEX FRETFeb 05 2012Thermophilic enzymes can operate at higher temperatures but show reduced activities at room temperature. They are in general more stable during preparation and, accordingly, are considered to be more rigid in structure. Crystallization is often easier ... More
An Artificial Intelligence-Based System for Nutrient Intake Assessment of Hospitalised PatientsJun 07 2019Regular nutrient intake monitoring in hospitalised patients plays a critical role in reducing the risk of disease-related malnutrition (DRM). Although several methods to estimate nutrient intake have been developed, there is still a clear demand for a ... More
Characterization of Disorder in Semiconductors via Single-Photon InterferometryNov 15 2006The method of angular photonic correlations of spontaneous emission is introduced as an experimental, purely optical scheme to characterize disorder in semiconductor nanostructures. The theoretical expression for the angular correlations is derived and ... More
An Artificial Intelligence-Based System for Nutrient Intake Assessment of Hospitalised PatientsJun 07 2019Jun 12 2019Regular nutrient intake monitoring in hospitalised patients plays a critical role in reducing the risk of disease-related malnutrition (DRM). Although several methods to estimate nutrient intake have been developed, there is still a clear demand for a ... More
Spin dynamics and coherent tunnelling in the molecular magnetic rings Fe_6 and Fe_8Sep 11 2001Apr 16 2002We present detailed calculations of low-energy spin dynamics in the ``ferric wheel'' systems Na:Fe_6 and Cs:Fe_8 in a magnetic field. We compute by exact diagonalisation the low-energy spectra and matrix elements for total-spin and N'eel-vector components, ... More
Non-CMC solutions of the Einstein constraint equations on asymptotically Euclidean manifoldsDec 02 2013In this note we prove two existence theorems for the Einstein constraint equations on asymptotically Euclidean manifolds. The first is for arbitrary mean curvature functions with restrictions on the size of the transverse-traceless data and the non-gravitational ... More
Bremsstrahlung Pair Production In Relativistic Heavy Ion CollisionJul 14 1997We calculate production of electron- and muon-pairs by the bremsstrahlung process in hadron collisions and compare it with the dominant two-photon process. Results for the total cross section are given for proton-proton and heavy-ion collisions at energies ... More
Two-dimensional imaging of the spin-orbit effective magnetic fieldDec 07 2007We report on spatially resolved measurements of the spin-orbit effective magnetic field in a GaAs/InGaAs quantum-well. Biased gate electrodes lead to an electric-field distribution in which the quantum-well electrons move according to the local orientation ... More
Fragile entanglement statisticsMay 07 2015Aug 25 2015If X and Y are independent, Y and Z are independent, and so are X and Z, one might be tempted to conclude that X, Y, and Z are independent. But it has long been known in classical probability theory that, intuitive as it may seem, this is not true in ... More
Quantum splinesJun 12 2012Sep 04 2012A quantum spline is a smooth curve parameterised by time in the space of unitary transformations, whose associated orbit on the space of pure states traverses a designated set of quantum states at designated times, such that the trace norm of the time ... More
Enumeration in Incremental FPT-TimeApr 20 2018Aug 27 2018In this paper, we study the relationship of parametrised enumeration complexity classes defined by Creignou et al. (MFCS 2013). Specifically, we introduce two hierarchies (IncFPTa and CapIncFPTa) of enumeration complexity classes for incremental fpt-time ... More
Additive decompositions for rings of modular formsOct 10 2017Feb 02 2018We study rings of integral modular forms for congruence subgroups as modules over the ring of integral modular forms for the full modular group. In many cases these modules are free or decompose at least into well-understood pieces. We apply this to characterize ... More
CHerenkov detectors In mine PitS (CHIPS) Letter of Intent to FNALJul 23 2013Sep 23 2013This Letter of Intent outlines a proposal to build a large, yet cost-effective, 100 kton fiducial mass water Cherenkov detector that will initially run in the NuMI beam line. The CHIPS detector (CHerenkov detector In Mine PitS) will be deployed in a flooded ... More
On the quantifier-free dynamic complexity of ReachabilityJun 13 2013Jan 28 2015The dynamic complexity of the reachability query is studied in the dynamic complexity framework of Patnaik and Immerman, restricted to quantifier-free update formulas. It is shown that, with this restriction, the reachability query cannot be dynamically ... More
An optimization principle for the computation of MHD equilibria in the solar coronaDec 21 2006AIMS: We develop an optimization principle for computing stationary MHD equilibria. METHODS: Our code for the self-consistent computation of the coronal magnetic fields and the coronal plasma uses non-force-free MHD equilibria. Previous versions of the ... More
Two-Variable Logic with Two Order RelationsOct 07 2011Mar 03 2012It is shown that the finite satisfiability problem for two-variable logic over structures with one total preorder relation, its induced successor relation, one linear order relation and some further unary relations is EXPSPACE-complete. Actually, EXPSPACE-completeness ... More
Causes and Explanations in the Structural-Model Approach: Tractable CasesDec 12 2012In this paper, we continue our research on the algorithmic aspects of Halpern and Pearl's causes and explanations in the structural-model approach. To this end, we present new characterizations of weak causes for certain classes of causal models, which ... More
On the boundedness of an iteration involving points on the hypersphereJan 11 2010Oct 05 2010For a finite set of points $X$ on the unit hypersphere in $\mathbb{R}^d$ we consider the iteration $u_{i+1}=u_i+\chi_i$, where $\chi_i$ is the point of $X$ farthest from $u_i$. Restricting to the case where the origin is contained in the convex hull of ... More
Transient photon echoes from donor-bound excitons in ZnO epitaxial layersFeb 16 2017The coherent optical response from 140~nm and 65~nm thick ZnO epitaxial layers is studied using transient four-wave-mixing spectroscopy with picosecond temporal resolution. Resonant excitation of neutral donor-bound excitons results in two-pulse and three-pulse ... More