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Guarded Open Answer Set Programming [chapter]

Stijn Heymans, Davy Van Nieuwenborgh, Dirk Vermeir
2005 Lecture Notes in Computer Science  
Open answer set programming (OASP) is an extension of answer set programming where one may ground a program with an arbitrary superset of the program's constants.  ...  We define a fixed point logic (FPL) extension of Clark's completion such that open answer sets correspond to models of FPL formulas and identify a syntactic subclass of programs, called (loosely) guarded  ...  (loosely) guarded OASP was shown to be 2-EXPTIME-complete.  ... 
doi:10.1007/11546207_8 fatcat:piqji2myz5anvhlzgcjxxawmvy

Open Answer Set Programming with Guarded Programs [article]

Stijn Heymans, Davy Van Nieuwenborgh, Dirk Vermeir
2007 arXiv   pre-print
Open answer set programming (OASP) is an extension of answer set programming where one may ground a program with an arbitrary superset of the program's constants.  ...  We define a fixed point logic (FPL) extension of Clark's completion such that open answer sets correspond to models of FPL formulas and identify a syntactic subclass of programs, called (loosely) guarded  ...  OPEN ANSWER SET PROGRAMMING WITH GUARDED GENERALIZED PRO-GRAMS As we did in Section 4 for programs, we introduce in this section a notion of guardedness such that the FPL translation of guarded gPs falls  ... 
arXiv:cs/0603025v2 fatcat:3cvl4xjk6bhxhgjcaeijzkqvgu

Open answer set programming with guarded programs

Stijn Heymans, Davy Van Nieuwenborgh, Dirk Vermeir
2008 ACM Transactions on Computational Logic  
Open answer set programming (OASP) is an extension of answer set programming where one may ground a program with an arbitrary superset of the program's constants.  ...  We define a fixed point logic (FPL) extension of Clark's completion such that open answer sets correspond to models of FPL formulas and identify a syntactic subclass of programs, called (loosely) guarded  ...  OPEN ANSWER SET PROGRAMMING WITH GUARDED GENERALIZED PRO-GRAMS As we did in Section 4 for programs, we introduce in this section a notion of guardedness such that the FPL translation of guarded gPs falls  ... 
doi:10.1145/1380572.1380575 fatcat:4czeusi3pjh6jlxga3k4fjrjje

Guarded Open Answer Set Programming with Generalized Literals [chapter]

Stijn Heymans, Davy Van Nieuwenborgh, Dirk Vermeir
2006 Lecture Notes in Computer Science  
We extend the open answer set semantics for programs with generalized literals.  ...  Finally, we discuss ω-restricted logic programs under an open answer set semantics.  ...  An open interpretation (U, M ) of P is an open answer set of P iff (U, M ) is an open answer set of P f . Proposition 5 . 5 Let P be a fully guarded p-EP.  ... 
doi:10.1007/11663881_11 fatcat:prjsvmhkgzeg3ivelze5zag4hy

Guarded Hybrid Knowledge Bases [article]

Stijn Heymans, Jos de Bruijn, Livia Predoiu, Cristina Feier, Davy Van Nieuwenborgh
2007 arXiv   pre-print
Decidability of satisfiability checking of g-hybrid knowledge bases is shown for the particular DL DLRO, which is close to OWL DL, by a reduction to guarded programs under the open answer set semantics  ...  G-hybrid knowledge bases enable an integration of Description Logics and Logic Programming where, unlike in other approaches, variables in the rules of a guarded program do not need to appear in positive  ...  We show several computational properties by a reduction to guarded open answer set programming (?; ?). References Open answer set programming (OASP) (?; ?)  ... 
arXiv:0711.2155v1 fatcat:vteqertlzbhpzmfjb32wdl5muu

Guarded hybrid knowledge bases

STIJN HEYMANS, JOS DE BRUIJN, LIVIA PREDOIU, CRISTINA FEIER, DAVY VAN NIEWENBORGH
2008 Theory and Practice of Logic Programming  
answer set semantics.  ...  Decidability of satisfiability checking of g-hybrid knowledge bases is shown for the particular DL$\mathcal{DLRO}^{\-{le}}$, which is close to OWL DL, by a reduction to guarded programs under the open  ...  An open answer set of P is an open interpretation (U, M ) of P with M an answer set of P U .  ... 
doi:10.1017/s1471068407003201 fatcat:2gyemstkvbaj5okdifr4lynwe4

Queries with guarded negation

Vince Bárány, Balder ten Cate, Martin Otto
2012 Proceedings of the VLDB Endowment  
computationally well behaved, in terms of testing query containment, query evaluation, open-world query answering, and boundedness.  ...  Inspired by recent results in finite model theory, we consider a restricted form of negation, guarded negation.  ...  In each of these settings, open world query answering is an extensively researched problem.  ... 
doi:10.14778/2350229.2350250 fatcat:aripunuyezfhrpdaslsci3lspu

Queries with Guarded Negation (full version) [article]

Vince Barany, Balder ten Cate, Martin Otto
2012 arXiv   pre-print
computationally well behaved, in terms of testing query containment, query evaluation, open-world query answering, and boundedness.  ...  Inspired by recent results in finite model theory, we consider a restricted form of negation, guarded negation.  ...  In each of these settings, open world query answering is an extensively researched problem.  ... 
arXiv:1203.0077v1 fatcat:bdcauk25nffedhieb74vtalnrq

Provenance Circuits for Trees and Treelike Instances [chapter]

Antoine Amarilli, Pierre Bourhis, Pierre Senellart
2015 Lecture Notes in Computer Science  
" answer that is the input to a Datalog program.  ...  The set of answers of a UCQ Q[x] over I is its extension.  ... 
doi:10.1007/978-3-662-47666-6_5 fatcat:dpatpbav7fgblnbvfsx6dbr6k4

Guards, Failure, and Partiality: Dijkstra's Guarded-Command Language Formulated Topologically [chapter]

David A. Schmidt
2015 Lecture Notes in Computer Science  
The results refine existing work, give a sound semantics of guards, failure, and divergence for non-flat storage domains, and reveal the important role that general topology plays in program correctness  ...  Existing treatments of Dijkstra's guarded-command language treat divergence and failure as equivalent, even though Dijkstra clearly states they are not.  ...  A function f : IR → IR is topologically continuous when it maps arguments "close together" (sharing many open sets) to answers "close together" (sharing equally many open sets), e.g., area(r) = πr 2 is  ... 
doi:10.1007/978-3-319-27810-0_13 fatcat:kwxmwiq56bfiheww34izrd2vkm

Web Question Answering with Neurosymbolic Program Synthesis [article]

Qiaochu Chen, Aaron Lamoreaux, Xinyu Wang, Greg Durrett, Osbert Bastani, Isil Dillig
2021 arXiv   pre-print
Our experiments show that WebQA significantly outperforms existing tools such as state-of-the-art question answering models and wrapper induction systems.  ...  In this paper, we propose a new technique based on program synthesis for extracting information from webpages.  ...  In particular, a branch program ∈ is a pair ( , ) consisting of a guard and an extractor, and we represent a set of branch programs as a mapping from guards to a set of extractors .  ... 
arXiv:2104.07162v1 fatcat:giptivbcordm7k2cnvisxipbtu

The Impact of Disjunction on Reasoning under Existential Rules: Research Summary [article]

Michael Morak
2014 arXiv   pre-print
For guarded theories with disjunction, we obtain a strong 2EXP lower bound in the combined complexity, even for very restricted formalisms like fixed sets of (disjunctive) inclusion dependencies.  ...  namely guarded, sticky and weakly-acyclic Datalog+/- theories.  ...  Open Issues and Expected Achievements In addition to the published results, we would like to find answers to the following questions: What is the complexity of query answering under sets of 1. guarded-based  ... 
arXiv:1405.5109v1 fatcat:4al4oxnkenb7pe3q64zqgtfet4

Some Model Theory of Guarded Negation [article]

Vince Barany, Michael Benedikt, Balder ten Cate
2020 arXiv   pre-print
The Guarded Negation Fragment (GNFO) is a fragment of first-order logic that contains all positive existential formulas, can express the first-order translations of basic modal logic and of many description  ...  Our results include effective preservation theorems for GNFO, effective Craig Interpolation and Beth Definability results, and the ability to express the certain answers of queries with respect to a large  ...  We will need to require answer-guardedness in some of our results involving open formulas. 2 Most results about GNFO sentences trivially generalize to answerguarded GNFO formulas.  ... 
arXiv:2005.06299v2 fatcat:awujhhdh6bgrrgs3xu3v7igz4u

Query-directed adaptive heap cloning for optimizing compilers

Yulei Sui, Yue Li, Jingling Xue
2013 Proceedings of the 2013 IEEE/ACM International Symposium on Code Generation and Optimization (CGO)  
positively at iteration k = i may now be answered more precisely.  ...  In contrast, k-callsite-sensitive heap cloning can be faster but less precise for some programs.  ...  This work has opened up some new research opportunities.  ... 
doi:10.1109/cgo.2013.6494978 dblp:conf/cgo/SuiLX13 fatcat:kignyd3pkzfalecmtoq7ep5z3q

Well-founded semantics for extended datalog and ontological reasoning

André Hernich, Clemens Kupke, Thomas Lukasiewicz, Georg Gottlob
2013 Proceedings of the 32nd symposium on Principles of database systems - PODS '13  
set semantics, and coincides with the canonical model in case of stratified normal programs.  ...  We prove that for guarded Datalog ± with negation under the standard WFS, answering normal Boolean conjunctive queries is decidable, and we provide precise complexity results for this problem, namely,  ...  A guarded (normal) Datalog ± program is a finite set of guarded (N)TGDs.  ... 
doi:10.1145/2463664.2465229 dblp:conf/pods/HernichKLG13 fatcat:t7rioz4oobgj3i5pptex7aegpq
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