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Understanding Model Counting for beta-acyclic CNF-formulas
We extend the knowledge about so-called structural restrictions of $\mathrm{\#SAT}$ by giving a polynomial time algorithm for $\beta$-acyclic $\mathrm{\#SAT}$. In contrast to previous algorithms inExpand
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Constant-Delay Enumeration for Nondeterministic Document Spanners
We consider the information extraction approach known as document spanners, and study the problem of efficiently computing the results of the extraction from an input document, where the extractionExpand
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Knowledge Compilation Meets Communication Complexity
Choosing a language for knowledge representation and reasoning involves a trade-off between two competing desiderata: succinctness (the encoding should be small) and tractability (the language shouldExpand
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Lower bounds on the mim-width of some graph classes
  • S. Mengel
  • Mathematics, Computer Science
  • Discret. Appl. Math.
  • 4 August 2016
Abstract mim-width is a recent graph width measure that has seen applications in graph algorithms and problems related to propositional satisfiability. In this paper, we show linear lower bounds forExpand
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NIR Spectroscopy of the Most Massive Open Cluster in the Galaxy: Westerlund 1
Using ISAAC/VLT, we have obtained individual spectra of all NIR-bright stars in the central 2'x2' of the cluster Westerlund 1 (Wd 1) with a resolution of R~9000 at a central wavelength of 2.30Expand
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A Trichotomy in the Complexity of Counting Answers to Conjunctive Queries
Conjunctive queries are basic and heavily studied database queries; in relational algebra, they are the select-project-join queries. In this article, we study the fundamental problem of counting,Expand
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QBF as an Alternative to Courcelle's Theorem
We propose reductions to quantified Boolean formulas (QBF) as a new approach to showing fixed-parameter linear algorithms for problems parameterized by treewidth. We demonstrate the feasibility ofExpand
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A Circuit-Based Approach to Efficient Enumeration
We study the problem of enumerating the satisfying valuations of a circuit while bounding the delay, i.e., the time needed to compute each successive valuation. We focus on the class of structuredExpand
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Structural Tractability of Counting of Solutions to Conjunctive Queries
We explore the complexity of counting solutions to conjunctive queries, a basic class of queries from database theory. We introduce a parameter, called the quantified star size of a query ϕ, whichExpand
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Enumeration on Trees under Relabelings
We study how to evaluate MSO queries with free variables on trees, within the framework of enumeration algorithms. Previous work has shown how to enumerate answers with linear-time preprocessingExpand
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