Results for "Rasmus Ischebeck"

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Adaptive and Safe Bayesian Optimization in High Dimensions via One-Dimensional SubspacesFeb 08 2019May 28 2019Bayesian optimization is known to be difficult to scale to high dimensions, because the acquisition step requires solving a non-convex optimization problem in the same search space. In order to scale the method and keep its benefits, we propose an algorithm ... More
Adaptive and Safe Bayesian Optimization in High Dimensions via One-Dimensional SubspacesFeb 08 2019Bayesian optimization is known to be difficult to scale to high dimensions, because the acquisition step requires solving a non-convex optimization problem in the same search space. In order to scale the method and keep its benefits, we propose an algorithm ... More
CoveringLSH: Locality-sensitive Hashing without False NegativesJul 12 2015Jan 07 2016We consider a new construction of locality-sensitive hash functions for Hamming space that is \emph{covering} in the sense that is it guaranteed to produce a collision for every pair of vectors within a given radius $r$. The construction is \emph{efficient} ... More
Homotopy-theoretic E-theory and n-orderFeb 27 2013May 13 2013The bootstrap category in E-theory for C*-algebras over a finite space X is embedded into the homotopy category of certain diagrams of K-module spectra. Therefore it has infinite n-order for every n. The same holds for the bootstrap category in G-equivariant ... More
Compressed Matrix MultiplicationAug 05 2011Nov 28 2011Motivated by the problems of computing sample covariance matrices, and of transforming a collection of vectors to a basis where they are sparse, we present a simple algorithm that computes an approximation of the product of two n-by-n real matrices A ... More
Signatures of long-lived colored sparticlesSep 28 2009In this paper an updated Geant4 simulation toolkit is presented describing the interactions in matter of heavy hadrons containing long-lived squarks and gluinos. Generic signatures are derived that are applicable at the Large Hadron Collider, and the ... More
Exploring the Galaxy using space probesJan 09 2007Apr 23 2007This paper investigates the possible use of space probes to explore the Milky Way, as a means both of finding life elsewhere in the Galaxy and as finding an answer to the Fermi paradox. I simulate exploration of the Galaxy by first examining how long ... More
Cuntz Splice invariance for purely infinite graph algebrasOct 22 2015Nov 30 2015We show that the Cuntz Splice preserves the stable isomorphism class of a purely infinite graph C*-algebra with finitely many ideals.
Bibliometric author evaluation through linear regression on the coauthor networkApr 13 2015The rising trend of coauthored academic works obscures the credit assignment that is the basis for decisions of funding and career advancements. In this paper, a simple model based on the assumption of an unvarying "author ability" is introduced. With ... More
The mapping class group orbit of a multicurveFeb 21 2008Mar 16 2009Given a set equipped with a transitive action of a group, we define the notion of an almost invariant coloring of the set. We consider the mapping class group orbit of a multicurve on a compact surface, and prove that in the case of genus at least two, ... More
Extensions of Cuntz-Krieger algebrasNov 30 2015We show that a C*-algebra "looking like" a Cuntz-Krieger algebra is a Cuntz-Krieger algebra. This implies that, in an appropriate sense, the class of Cuntz-Krieger algebras is closed under extensions of real rank zero.
Kirchberg X-algebras with real rank zero and intermediate cancellationJan 28 2013Nov 04 2013A universal coefficient theorem is proved for C*-algebras over an arbitrary finite T_0-space X which have vanishing boundary maps. Under bootstrap assumptions, this leads to a complete classification of unital/stable real-rank-zero Kirchberg X-algebras ... More
Projective dimension in filtrated K-theoryOct 17 2012Jan 11 2013Under mild assumptions, we characterise modules with projective resolutions of length n in the target category of filtrated K-theory over a finite topological space in terms of two conditions involving certain Tor-groups. We show that the filtrated K-theory ... More
A computation of H^1(Γ, H_1(Σ))Feb 23 2011Let \Sigma = \Sigma _{g,1} be a compact surface of genus g at least 3 with one boundary component, \Gamma its mapping class group and M = H_1(\Sigma , Z) the first integral homology of \Sigma . Using that \Gamma is generated by the Dehn twists in a collection ... More
Hierarchical incompleteness results for arithmetically definable fragments of arithmeticMar 05 2018There has been a recent interest in hierarchical generalisations of classic incompleteness results. This paper provides evidence that such generalisations are readibly obtainable from suitably hierarchical versions of the principles used in the original ... More
A Review of the Holographic Relation between Linearized Gravity and the First Law of Entanglement EntropyNov 29 2017This thesis reviews the conjectured holographic relation between entanglement and gravity due to Mark van Raamsdonk and collaborators. It is accounted how the linearized Einstein equations both with and without matter in a d+1-dimensional AdS background ... More
Non-advective rate of curved step advance on smooth crystal face under steady-state conditionsJan 13 2009Apr 02 2014For low to moderate supersaturations, crystals grow by lateral build-up of new layers. The edges of the layers are known as "steps". We consider the rate of step advance on a flat crystal face under the influence of bulk diffusion in the complete absence ... More
Classification of certain continuous fields of Kirchberg algebrasAug 09 2013Dec 19 2013We show that the K-theory cosheaf is a complete invariant for separable continuous fields with vanishing boundary maps over a finite-dimensional compact metrizable topological space whose fibers are stable Kirchberg algebras with rational K-theory groups ... More
A New Data Layout For Set Intersection on GPUsFeb 04 2011Set intersection is the core in a variety of problems, e.g. frequent itemset mining and sparse boolean matrix multiplication. It is well-known that large speed gains can, for some computational problems, be obtained by using a graphics processing unit ... More
Opportunities in Machine Learning for Particle AcceleratorsNov 07 2018Machine learning (ML) is a subfield of artificial intelligence. The term applies broadly to a collection of computational algorithms and techniques that train systems from raw data rather than a priori models. ML techniques are now technologically mature ... More
Better size estimation for sparse matrix productsJun 21 2010Feb 22 2011We consider the problem of doing fast and reliable estimation of the number of non-zero entries in a sparse boolean matrix product. This problem has applications in databases and computer algebra. Let n denote the total number of non-zero entries in the ... More
Energy efficiency studies for dual-grating dielectric laser-driven acceleratorsDec 13 2017Dielectric laser-driven accelerators (DLAs) can provide high accelerating gradients in the GV/m range due to their having higher breakdown thresholds than metals, which opens the way for the miniaturization of the next generation of particle accelerator ... More
Generation and Measurement of Sub-Micrometer Relativistic Electron BeamsApr 11 2018The generation of low-emittance electron beams has received significant interest in recent years. Driven by the requirements of X-ray free electron lasers, the emittance of photocathode injectors has been reduced significantly, with a corresponding increase ... More
Error-prone polymerase activity causes multinucleotide mutations in humansDec 05 2013Apr 29 2014About 2% of human genetic polymorphisms have been hypothesized to arise via multinucleotide mutations (MNMs), complex events that generate SNPs at multiple sites in a single generation. MNMs have the potential to accelerate the pace at which single genes ... More
Validating a physics-based back-of-the-envelope climate model with state-of-the-art dataJan 07 2013Mar 04 2013An old conceptual physics-based back-of-the-envelope model for greenhouse effect is revisited and validated against state-of-the-art reanalyses. Untraditional diagnostics show a physically consistent picture, for which the state of earth's climate is ... More
Vertical partitioning of relational OLTP databases using integer programmingNov 09 2009Feb 16 2010A way to optimize performance of relational row store databases is to reduce the row widths by vertically partitioning tables into table fractions in order to minimize the number of irrelevant columns/attributes read by each transaction. This paper considers ... More
Diffusion, Influence and Best-Response Dynamics in Networks: An Action Model ApproachAug 04 2017Threshold models and their dynamics may be used to model the spread of `behaviors' in social networks. Regarding such from a modal logical perspective, it is shown how standard update mechanisms may be emulated using action models -- graphs encoding agents' ... More
Correlations and fluctuations of the gauge topology at finite temperaturesMar 07 2017Instanton-dyons are topological solitons -- solutions of Yang-Mills equations -- which appear at non-trivial expectation value of $A_0$ at nonzero temperatures. Using the ensembles of those, generated in our previous work, for 2-color and 2-flavor QCD, ... More
Injective envelopes and the intersection propertyApr 10 2017Sep 13 2017We consider the center of Hamana's equivariant injective envelope of a unital $C^*$-algebra equipped with an action of a discrete group. We show that the center of the equivariant injective envelope always contains a $^*$-algebraic copy of the equivariant ... More
Generating k-independent variables in constant timeAug 09 2014The generation of pseudorandom elements over finite fields is fundamental to the time, space and randomness complexity of randomized algorithms and data structures. We consider the problem of generating $k$-independent random values over a finite field ... More
Association Rule Mining using Maximum EntropyJan 09 2015Recommendations based on behavioral data may be faced with ambiguous statistical evidence. We consider the case of association rules, relevant e.g.~for query and product recommendations. For example: Suppose that a customer belongs to categories A and ... More
Comment on "Calculation of microcanonical entropy differences from configurational averages"Mar 25 2013May 06 2013We introduce a simple improvement on the method to calculate equilibrium entropy differences between classical energy levels proposed by Davis (S. Davis, Phys. Rev. E, 050101, 2011). We demonstrate that the modification is superior to the original whenever ... More
A parametric study of the meso-scale modelling of concrete subjected to cyclic compressionNov 08 2008The present parametric study deals with the meso-scale modelling of concrete subjected to cyclic compression, which exhibits hysteresis loops during unloading and reloading. Concrete is idealised as a two-dimensional three-phase composite made of aggregates, ... More
Discovery of the progenitor of the type Ia supernova 2007onFeb 14 2008Type Ia supernovae are exploding stars that are used to measure the accelerated expansion of the Universe and are responsible for most of the iron ever produced. Although there is general agreement that the exploding star is a white dwarf in a binary ... More
Range-efficient consistent sampling and locality-sensitive hashing for polygonsJan 19 2017Sep 22 2017Locality-sensitive hashing (LSH) is a fundamental technique for similarity search and similarity estimation in high-dimensional spaces. The basic idea is that similar objects should produce hash collisions with probability significantly larger than objects ... More
Picasso: A Modular Framework for Visualizing the Learning Process of Neural Network Image ClassifiersMay 16 2017Sep 11 2017Picasso is a free open-source (Eclipse Public License) web application written in Python for rendering standard visualizations useful for analyzing convolutional neural networks. Picasso ships with occlusion maps and saliency maps, two visualizations ... More
On the tail behavior of a class of multivariate conditionally heteroskedastic processesJan 18 2017Dec 05 2017Conditions for geometric ergodicity of multivariate autoregressive conditional heteroskedasticity (ARCH) processes, with the so-called BEKK (Baba, Engle, Kraft, and Kroner) parametrization, are considered. We show for a class of BEKK-ARCH processes that ... More
Consistent Subset SamplingApr 18 2014Consistent sampling is a technique for specifying, in small space, a subset $S$ of a potentially large universe $U$ such that the elements in $S$ satisfy a suitably chosen sampling condition. Given a subset $\mathcal{I}\subseteq U$ it should be possible ... More
Gaussian-Charge Polarizable Interaction Potential for Carbon DioxideAug 23 2010Oct 23 2010A number of simple pair interaction potentials of the carbon dioxide molecule are investigated and found to underestimate the magnitude of the second virial coefficient in the temperature interval 220 K to 448 K by up to 20%. Also the third virial coefficient ... More
Succinct Data Structures for Retrieval and Approximate MembershipMar 26 2008The retrieval problem is the problem of associating data with keys in a set. Formally, the data structure must store a function f: U ->{0,1}^r that has specified values on the elements of a given set S, a subset of U, |S|=n, but may have any value on ... More
Verifiable Light-Weight Monitoring for Certificate Transparency LogsNov 10 2017Oct 28 2018Trust in publicly verifiable Certificate Transparency (CT) logs is reduced through cryptography, gossip, auditing, and monitoring. The role of a monitor is to observe each and every log entry, looking for suspicious certificates that interest the entity ... More
One-parameter continuous fields of Kirchberg algebras with rational K-theoryJun 07 2013Nov 04 2013We show that separable continuous fields over the unit interval whose fibers are stable Kirchberg algebras that satisfy the universal coefficient theorem in KK-theory and have rational K-theory groups are classified up to isomorphism by filtrated K-theory. ... More
Numerical Valuation of Derivatives in High-Dimensional Settings via PDE ExpansionsSep 10 2012Oct 03 2013In this article, we propose a new numerical approach to high-dimensional partial differential equations (PDEs) arising in the valuation of exotic derivative securities. The proposed method is extended from Reisinger and Wittum (2007) and uses principal ... More
A study of the population of LMXBs in the bulge of M31Oct 21 2006Mar 21 2007The purpose of this study is to explore the population of X-ray point sources in the bulge of M31, with the primary goal to contrast properties of various subpopulations, such as persistent and transient sources, primordial LMXBs and dynamically formed ... More
Classical interactions of the instanton-dyons with antidyonsAug 27 2014Apr 29 2016Instanton-dyons, also known as instanton-monopoles or instanton-quarks, are topological constituents of the instantons at nonzero temperature and nonzero expectation value of $A_4$. While the interaction between instanton-dyons has been calculated to ... More
On Finding Similar Items in a Stream of TransactionsOct 12 2010While there has been a lot of work on finding frequent itemsets in transaction data streams, none of these solve the problem of finding similar pairs according to standard similarity measures. This paper is a first attempt at dealing with this, arguably ... More
On Finding Frequent Patterns in Event SequencesOct 12 2010Given a directed acyclic graph with labeled vertices, we consider the problem of finding the most common label sequences ("traces") among all paths in the graph (of some maximum length m). Since the number of paths can be huge, we propose novel algorithms ... More
Instanton-dyon Ensemble with two Dynamical Quarks: the Chiral Symmetry BreakingNov 06 2015Apr 29 2016This is the second paper of the series aimed at understanding the ensemble of instanton-dyons, now with two flavors of light dynamical quarks. The partition function is appended by the fermionic factor, $(det T)^{N_f}$ and Dirac eigenvalue spectra at ... More
The scenario-based generalization of radiation therapy marginsOct 09 2015We give a scenario-based treatment plan optimization formulation that is equivalent to planning with geometric margins if the scenario doses are calculated using the static dose cloud approximation. If the scenario doses are instead calculated more accurately, ... More
Interacting Ensemble of the Instanton-dyons and Deconfinement Phase Transition in the SU(2) Gauge TheoryApr 13 2015Instanton-dyons, also known as instanton-monopoles or instanton-quarks, are topological constituents of the instantons at nonzero temperature and holonomy. We perform numerical simulations of the ensemble of interacting dyons for the SU(2) pure gauge ... More
Joint Coordinated Precoding and Discrete Rate Selection in Multicell MIMO NetworksApr 19 2016Many practical wireless communications systems select their transmit rate from a finite set of modulation and coding schemes, which correspond to a set of discrete rates. In this paper, we therefore formulate a joint coordinated precoding and discrete ... More
A more general method to classify up to equivariant KK-equivalenceMay 26 2014Nov 30 2015Using a homological invariant together with an obstruction class in a certain Ext^2-group, we may classify objects in triangulated categories that have projective resolutions of length two. This invariant gives strong classification results for actions ... More
Universal coefficient theorems for C*-algebras over finite topological spacesJan 29 2011Apr 07 2011We determine the class of finite T_0-spaces allowing for a universal coefficient theorem computing equivariant KK-theory by filtrated K-theory.
Necessary and sufficient conditions for Pareto efficiency in robust multiobjective optimizationAug 21 2013Nov 27 2014We provide necessary and sufficient conditions for robust efficiency to multiobjective optimization problems with uncertain objectives. These conditions state that a solution is robust efficient (under minimization) if it is optimal to a strongly increasing ... More
Note on the physical basis of spatially resolved thermodynamic functionsApr 25 2016The spatial resolution of thermodynamic functions, exemplified by the entropy, is discussed. A physical definition of the spatial resolution based on a spatial analogy of the partial molar entropy is advocated. It is shown that neither the grid cell theory ... More
Error analysis of truncated expansion solutions to high-dimensional parabolic PDEsMay 18 2015Nov 07 2016We study an expansion method for high-dimensional parabolic PDEs which constructs accurate approximate solutions by decomposition into solutions to lower-dimensional PDEs, and which is particularly effective if there are a low number of dominant principal ... More
Instanton-dyon Ensembles III: Exotic Quark FlavorsMay 24 2016Jun 15 2016"Exotic quarks" in the title refers to a modification of quark periodicity condition on the thermal circle by introduction of some phases -- known also as "flavor holonomies" -- different quark flavors. These phases provide a valuable tool, to be used ... More
Simple Multi-Party Set ReconciliationNov 08 2013Apr 22 2015As users migrate information to cloud storage, many distributed cloud-based services use multiple loosely consistent replicas of user information to avoid the high overhead of more tightly coupled synchronization. Periodically, the information must be ... More
Modification of the Gay-Berne potential for improved accuracy and speedMay 07 2012May 27 2012A modification of the Gay-Berne potential is proposed which is about 10% to 20% more speed efficient (that is, the original potential runs 15% to 25% slower, depending on architecture) and statistically more accurate in reproducing the energy of interaction ... More
New Evidence of an Enhanced Greenhouse EffectJun 24 2011The state of earth's climate is constrained by well-known physical principles such as energy balance and the conservation of energy. Increased greenhouse gas concentrations affect the atmospheric optical depth, and physical consistency implies that changes ... More
The dynamical formation of LMXBs in dense stellar environments: globular clusters and the inner bulge of M31Feb 21 2007Sep 21 2007The radial distribution of luminous L_X>10^{36} erg/s X-ray point sources in the bulge of M31 is investigated using archival Chandra observations. We find a significant increase of the specific frequency of X-ray sources, per unit stellar mass, within ... More
On Finding Frequent Patterns in Directed Acyclic GraphsMay 03 2010Given a directed acyclic graph with labeled vertices, we consider the problem of finding the most common label sequences ("traces") among all paths in the graph (of some maximum length m). Since the number of paths can be huge, we propose novel algorithms ... More
Hardness Results for Structured Linear SystemsMay 08 2017Sep 24 2017We show that if the nearly-linear time solvers for Laplacian matrices and their generalizations can be extended to solve just slightly larger families of linear systems, then they can be used to quickly solve all systems of linear equations over the reals. ... More
SMSSVD - SubMatrix Selection Singular Value DecompositionOct 23 2017High throughput biomedical measurements normally capture multiple overlaid biologically relevant signals and often also signals representing different types of technical artefacts like e.g. batch effects. Signal identification and decomposition are accordingly ... More
Error analysis of truncated expansion solutions to high-dimensional parabolic PDEsMay 18 2015Apr 22 2016We study an expansion method for high-dimensional parabolic PDEs which guarantees accurate approximate solutions in polynomial complexity in the dimension and which is particularly effective if there are a low number of dominant principal components. ... More
Hadronic Correlation Functions in the Random Instanton-dyon EnsembleMay 12 2017Jun 08 2017It is known since 1980's that the instanton-induced 't Hooft effective Lagrangian not only can solve the so called $U(1)a$ problem, by making the $\eta'$ meson heavy etc, but it can also lead to chiral symmetry breaking. In 1990's it was demonstrated ... More
A Matrix Chernoff Bound for Strongly Rayleigh Distributions and Spectral Sparsifiers from a few Random Spanning TreesOct 19 2018Strongly Rayleigh distributions are a class of negatively dependent distributions of binary-valued random variables [Borcea, Branden, Liggett JAMS 09]. Recently, these distributions have played a crucial role in the analysis of algorithms for fundamental ... More
Approximate Gaussian Elimination for Laplacians: Fast, Sparse, and SimpleMay 08 2016We show how to perform sparse approximate Gaussian elimination for Laplacian matrices. We present a simple, nearly linear time algorithm that approximates a Laplacian by a matrix with a sparse Cholesky factorization, the version of Gaussian elimination ... More
Bibliometric author evaluation through linear regression on the coauthor networkApr 13 2015Feb 06 2017The rising trend of coauthored academic works obscures the credit assignment that is the basis for decisions of funding and career advancements. In this paper, a simple model based on the assumption of an unvarying "author ability" is introduced. With ... More
Set Similarity Search Beyond MinHashDec 22 2016Apr 18 2017We consider the problem of approximate set similarity search under Braun-Blanquet similarity $B(\mathbf{x}, \mathbf{y}) = |\mathbf{x} \cap \mathbf{y}| / \max(|\mathbf{x}|, |\mathbf{y}|)$. The $(b_2, b_2)$-approximate Braun-Blanquet similarity search problem ... More
DEMoS ManifestoDec 11 2016This is a manifesto for DEMoS, which is a Distributed Embedded Modular System, but also a manifesto addressing the need for more inter-/cross-disciplinary mastery of working knowledge related to installing this class of systems in the real world. There ... More
Some recent developments in statistics for spatial point patternsSep 04 2016This paper reviews developments in statistics for spatial point processes obtained within roughly the last decade. These developments include new classes of spatial point process models such as determinantal point processes, models incorporating both ... More
Scalability and Total Recall with Fast CoveringLSHFeb 08 2016Aug 19 2016Locality-sensitive hashing (LSH) has emerged as the dominant algorithmic technique for similarity search with strong performance guarantees in high-dimensional spaces. A drawback of traditional LSH schemes is that they may have \emph{false negatives}, ... More
Necessary and sufficient conditions for Pareto efficiency in robust multiobjective optimizationAug 21 2013May 29 2017We provide necessary and sufficient conditions for robust efficiency (in the sense of Ehrgott et al. (2014)) to multiobjective optimization problems that depend on uncertain parameters. These conditions state that a solution is robust efficient (under ... More
Perturbation method to calculate the density of statesJul 16 2012Dec 19 2012Monte Carlo switching moves ("perturbations") are defined between two or more classical Hamiltonians sharing a common ground-state energy. The ratio of the density of states (DOS) of one system to that of another is related to the ensemble averages of ... More
On the Physical Cluster of Nucleation Theory: Generalized Hill ClusterNov 12 2011The physical cluster originally conceived by Hill (J. Chem. Phys, 23, 617) is generalized for the case $N > 2$ in a novel way. Contrary to Hill's pairwise generalization, this definition assures that all constituent molecules of the cluster have insufficient ... More
Finding Associations and Computing Similarity via Biased Pair SamplingOct 01 2009Feb 17 2010This version is ***superseded*** by a full version that can be found at http://www.itu.dk/people/pagh/papers/mining-jour.pdf, which contains stronger theoretical results and fixes a mistake in the reporting of experiments. Abstract: Sampling-based methods ... More
An Updated Description of Heavy-Hadron Interactions in Geant-4Aug 13 2009Sep 01 2009Exotic stable massive particles (SMP) are proposed in a number of scenarios of physics beyond the Standard Model. It is important that LHC experiments are able both to detect and extract the quantum numbers of any SMP with masses around the TeV scale. ... More
The Input/Output Complexity of Sparse Matrix MultiplicationMar 14 2014We consider the problem of multiplying sparse matrices (over a semiring) where the number of non-zero entries is larger than main memory. In the classical paper of Hong and Kung (STOC '81) it was shown that to compute a product of dense $U \times U$ matrices, ... More
The Input/Output Complexity of Triangle EnumerationDec 03 2013Mar 22 2014We consider the well-known problem of enumerating all triangles of an undirected graph. Our focus is on determining the input/output (I/O) complexity of this problem. Let $E$ be the number of edges, $M<E$ the size of internal memory, and $B$ the block ... More
Microscopic Spectral Density of the Wilson Dirac Operator for One FlavorOct 26 2011We consider the effect of a non-zero lattice spacing on the low-energy effective theory of Wilson fermions with one flavor. Analytical results are given for both the chiral condensate and the microscopic spectral density of the Wilson Dirac operator. ... More
Interactions of Coloured Heavy Stable Particles in MatterDec 13 2006In this paper we present a physics model for the interactions of stable heavy hadrons containing a heavy parton with matter. The model presented is a natural continuation of the work started in hep-ex/0404001. However, changes and generalisations have ... More
Realtime Tomography of Gas-Jets with a Wollaston InterferometerNov 07 2017Feb 23 2018A tomographic gas-density diagnostic using a single-beam Wollaston interferometer able to characterise non-symmetric density distributions in gas jets is presented. A real-time tomographic algorithm is able to reconstruct three dimensional density distributions. ... More
The Value 1 Problem Under Finite-memory Strategies for Concurrent Mean-payoff GamesSep 23 2014Oct 01 2014We consider concurrent mean-payoff games, a very well-studied class of two-player (player 1 vs player 2) zero-sum games on finite-state graphs where every transition is assigned a reward between 0 and 1, and the payoff function is the long-run average ... More
Thresholds for Extreme OrientabilityFeb 06 2012Feb 15 2012Multiple-choice load balancing has been a topic of intense study since the seminal paper of Azar, Broder, Karlin, and Upfal. Questions in this area can be phrased in terms of orientations of a graph, or more generally a k-uniform random hypergraph. A ... More
Characterization of the tail behavior of a class of BEKK processes: A stochastic recurrence equation approachFeb 22 2019We provide new, mild conditions for strict stationarity and ergodicity of a class of BEKK processes. By exploiting that the processes can be represented as multivariate stochastic recurrence equations, we characterize the tail behavior of the associated ... More
Nonnegative PARAFAC2: a flexible coupling approachFeb 14 2018Modeling variability in tensor decomposition methods is one of the challenges of source separation. One possible solution to account for variations from one data set to another, jointly analysed, is to resort to the PARAFAC2 model. However, so far imposing ... More
Denotational semantics of recursive types in synthetic guarded domain theoryMay 01 2018May 02 2018Just like any other branch of mathematics, denotational semantics of programming languages should be formalised in type theory, but adapting traditional domain theoretic semantics, as originally formulated in classical set theory to type theory has proven ... More
Convergence, Continuity and Recurrence in Dynamic Epistemic LogicSep 01 2017The paper analyzes dynamic epistemic logic from a topological perspective. The main contribution consists of a framework in which dynamic epistemic logic satisfies the requirements for being a topological dynamical system thus interfacing discrete dynamic ... More
The first cohomology of the mapping class group with coefficients in algebraic functions on the SL(2, C) moduli spaceFeb 29 2008Consider a compact surface of genus at least two. We prove that the first cohomology group of the mapping class group with coefficients in the space of algebraic functions on the SL(2, C) moduli space vanishes.
Chaotic flavor evolution in an interacting neutrino gasApr 15 2014Neutrino-neutrino refraction can lead to non-periodic flavor oscillations in dense neutrino gases, and it has been hypothesized that some solutions are chaotic in nature. This is of particular interest in the case of neutrino emission from core-collapse ... More
I/O-Efficient Data Structures for Colored Range and Prefix ReportingApr 15 2011Motivated by information retrieval applications, we consider the one-dimensional colored range reporting problem in rank space. The goal is to build a static data structure for sets C_1,...,C_m \subseteq {1,...,sigma} that supports queries of the kind: ... More
Reliable Reception of Wireless Metering Data with Protocol CodingMay 21 2013Stationary collectors reading wireless, battery powered smart meters, often operate in harsh channel conditions to cut network installation cost to a minimum, challenging the individual link to each meter. The desired performance measure is reliable reception ... More
Colorful Triangle Counting and a MapReduce ImplementationMar 31 2011In this note we introduce a new randomized algorithm for counting triangles in graphs. We show that under mild conditions, the estimate of our algorithm is strongly concentrated around the true number of triangles. Specifically, if $p \geq \max{(\frac{\Delta ... More
Turing Completeness of Finite, Epistemic ProgramsJun 21 2017In this note, we show the class of finite, epistemic programs to be Turing complete. Epistemic programs is a widely used update mechanism used in epistemic logic, where it such are a special type of action models: One which does not contain postconditions. ... More
The maximum theoretical performance of unconcentrated solar photovoltaic and thermoelectric generator systemsSep 18 2017Nov 14 2017The maximum efficiency for photovoltaic (PV) and thermoelectric generator (TEG) systems without concentration is investigated. Both a combined system where the TEG is mounted directly on the back of the PV and a tandem system where the incoming sunlight ... More
Linear usage of stateMar 06 2014Mar 30 2014We investigate the phenomenon that "every monad is a linear state monad". We do this by studying a fully-complete state-passing translation from an impure call-by-value language to a new linear type theory: the enriched call-by-value calculus. The results ... More
Strategy complexity of finite-horizon Markov decision processes and simple stochastic gamesSep 17 2012Markov decision processes (MDPs) and simple stochastic games (SSGs) provide a rich mathematical framework to study many important problems related to probabilistic systems. MDPs and SSGs with finite-horizon objectives, where the goal is to maximize the ... More
Relational Parametricity for Computational EffectsJun 30 2009Aug 09 2009According to Strachey, a polymorphic program is parametric if it applies a uniform algorithm independently of the type instantiations at which it is applied. The notion of relational parametricity, introduced by Reynolds, is one possible mathematical ... More
Bisimulation as path type for guarded recursive typesOct 31 2018In type theory, coinductive types are used to represent processes, and are thus crucial for the formal verification of non-terminating reactive programs in proof assistants based on type theory, such as Coq and Agda. Currently, programming and reasoning ... More