Commit 51610398 authored by Pietro Abate's avatar Pietro Abate
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[r2006-01-04 14:41:40 by beppe] Empty log message

Original author: beppe
Date: 2006-01-04 14:41:40+00:00
parent c9ac9697
<li>
<paper file="http://www.grappa.univ-lille3.fr/twiki/pub/Private/IovkaBoneva/BonevaTalbot-ModelChecking.pdf">
<title>On Complexity of Model-Checking for the TQL Logic</title>
<author>Iovka Boneva</author>
<author>Jean-Marc Talbot</author>
<comment>3rd IFIP International Conference on Theoretical Computer Science.</comment>
<abstract><p>In this paper we study the complexity of the model-checking problem for the tree logic introduced as the basis for the query language TQL [Cardelli, Ghelli 01: Query Language Based on the Ambient Logic]. We define two distinct fragments of this logic: TL containing only spatial connectives and TLe containing spatial connectives and quantification. We show that the combined complexity of TL is PSPACE-hard. We also study data complexity of model-checking and show that it is linear for TL, hard for all levels of the polynomial hierarchy for TLe and PSPACE-hard for the full logic. Finally we devise a polynomial space model-checking algorithm showing this way that the model-checking problem for the TQL logic is PSPACE-complete.</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.ps.uni-sb.de/Papers/abstracts/mini.html">
<title>Minimizing Tree Automata for Unranked Trees</title>
<author>Wim Martens</author>
<paper file="http://www.grappa.univ-lille3.fr/~terlutte/recherche/biRFSA.ps">
<author>Joachim Niehren</author>
<title>BiRFSA languages and minimal NFAs</title>
<comment>10th International Symposium on Database Programming Languages. Submitted.</comment>
<author>Michel Latteux</author>
<abstract><p>Automata for unranked trees form a foundation for XML schemas,
querying and pattern languages. We study the problem of efficiently
minimizing such automata. We start with the unranked tree automata
(UTAs) that are standard in database theory, assuming bottom-up
determinism and that horizontal recursion is represented by
deterministic finite automata. We show that minimal
UTAs in that class are not unique and that minimization
is NP-hard. We then study more recent automata classes that do allow for
polynomial time minimization. Among those, we show that bottom-up
deterministic stepwise tree automata yield the most succinct
representations.
</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.ps.uni-sb.de/Papers/paper_info.php?label=n-ary-query">
<title>N-ary Queries by Tree Automata </title>
<author>Joachim Niehren</author>
<author>Laurent Planque</author>
<author>Jean-Marc Talbot</author>
<author>Sophie Tison</author>
<comment>A previous version has been presented at the 19th International Workshop on Unification.</comment>
<abstract><p>N-ary queries in trees select sets of n-tuples of nodes. We propose and investigate representation formalisms for n-ary queries by tree automata, both for ranked and unranked trees. We show that existential run-based queries capture MSO in the \nary case as well as universal run-based queries. We then investigate queries by unambiguous tree automata that are relevant for query induction. We characterize queries by unambiguous automata by a natural fragment of MSO, show how to decide whether regular queries are definable in that fragment, and how to answer them efficiently in linear time. </p></abstract>
</paper>
</li>
<li>
<paper file="https://www.ps.uni-sb.de/Papers/abstracts/lambdafut.html">
<title>A Concurrent Lambda Calculus with Futures</title>
<author>Joachim Niehren </author>
<author> Jan Schwinghammer </author>
<author> Gert Smolka</author>
<comment>5th International Workshop on Frontiers in Combining Systems.</comment>
<abstract><p>
We introduce a new concurrent lambda calculus with futures,
lambda(fut), to model the operational semantics of Alice, a
concurrent extension of ML. lambda(fut) is a minimalist
extension of the call-by-value lambda-calculus that yields
the full expressiveness to define, combine, and implement
a variety of standard concurrency constructs such as channels,
semaphores, and ports. We present a linear type system for
lambda(fut) by which the safety of such definitions
and their combinations can be proved:
Well-typed implementations cannot be corrupted in any well-typed context.
</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.ps.uni-sb.de/Papers/abstracts/wellnested-cu.bib">
<title>Well-nested Context Unification</title>
<author>Jordi Levy </author>
<author> Joachim Niehren </author>
<author>Yves Roos</author>
<author> Mateu Villaret</author>
<author>Alain Terlutte</author>
<comment>20th International Conference on Automated Deduction.</comment>
<comment></comment>
<abstract><p>
Context unification (CU) is the famous open problem of
solving context equations for trees. We distinguish
a new decidable fragment of CU - well-nested CU -
and present a new unification algorithm that solves
well-nested context equations in non-deterministic
polynomial time. We show that minimal
well-nested solutions of context equations can be
composed from the material present in the equation.
This surprising property is highly wishful when
modeling natural language ellipsis in CU.
</p></abstract>
<abstract></abstract>
</paper>
</li>
......@@ -132,7 +29,7 @@
<author>Yves Roos</author>
<comment>Workshop on Logical Aspects and Applications of Integrity Constraints.</comment>
<comment>DEXA Workshop on Logical Aspects and Applications of Integrity Constraints.</comment>
<abstract><p>In this paper, we study semistructured data and indexes preserving
inclusion constraints.
......@@ -155,6 +52,21 @@ compare the different ways of using the 1-index to index a set of data.</p></abs
</paper>
</li>
<li>
<paper file="http://www.grappa.univ-lille3.fr/twiki/pub/Private/IovkaBoneva/BonevaTalbot-ModelChecking.pdf">
<title>On Complexity of Model-Checking for the TQL Logic</title>
<author>Iovka Boneva</author>
<author>Jean-Marc Talbot</author>
<comment>3rd IFIP International Conference on Theoretical Computer Science.</comment>
<abstract><p>In this paper we study the complexity of the model-checking problem for the tree logic introduced as the basis for the query language TQL [Cardelli, Ghelli 01: Query Language Based on the Ambient Logic]. We define two distinct fragments of this logic: TL containing only spatial connectives and TLe containing spatial connectives and quantification. We show that the combined complexity of TL is PSPACE-hard. We also study data complexity of model-checking and show that it is linear for TL, hard for all levels of the polynomial hierarchy for TLe and PSPACE-hard for the full logic. Finally we devise a polynomial space model-checking algorithm showing this way that the model-checking problem for the TQL logic is PSPACE-complete.</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.lifl.fr/~debarbie/DOC/ExtractionAndImplicationOfPathConstraints.pdf">
......@@ -211,6 +123,44 @@ regular constraints. </p></abstract>
</paper>
</li>
<li>
<paper file="http://www.lifl.fr/~yroos/stc/acta.pdf">
<title>Monotone AC-Tree Automata</title>
<author>Hitoshi Ohsaki</author>
<author>Jean-Marc Talbot</author>
<author>Sophie Tison</author>
<author>Yves Roos</author>
<comment>12th International Conference on Logic for Programming Artificial Intelligence and Reasoning.</comment>
<abstract><p>This paper considers several questions about
monotone AC-tree automata,
a class of equational tree automata
whose transition rules correspond to
rules in Kuroda normal form of context-sensitive grammars.
Whereas it has been proved that this class has a decision procedure
to determine if, given a monotone AC-tree automaton, it accepts
no terms,
other important decidability or complexity results have not been
well-investigated
yet. In the paper, it is proved that the membership problem for
monotone AC-tree automata is PSPACE-complete.
The expressiveness of monotone AC-tree automata is also studied:
precisely, it is proved that the family of AC-regular tree
languages is strictly subsumed in that of AC-monotone tree
languages. The proof technique used in obtaining the above
result yields the answers to two different questions, specifically
that the family of monotone AC-tree languages is not
closed under complementation, and that the inclusion problem
for monotone AC-tree automata is undecidable.</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.lifl.fr/~boneva/papers/lics2005.pdf">
......@@ -295,9 +245,38 @@ This work is a step towards resolving long-standing open problems of the decidab
</li>
<li>
<paper file="https://www.ps.uni-sb.de/Papers/abstracts/cut.html">
<paper file="https://www.ps.uni-sb.de/Papers/abstracts/lambdafut.html">
<title>A Concurrent Lambda Calculus with Futures</title>
<title>Interactive Learning of Node Selection Queries in Tree Structured Documents</title>
<author>Joachim Niehren </author>
<author> Jan Schwinghammer </author>
<author> Gert Smolka</author>
<comment>5th International Workshop on Frontiers in Combining Systems.</comment>
<abstract><p>
We introduce a new concurrent lambda calculus with futures,
lambda(fut), to model the operational semantics of Alice, a
concurrent extension of ML. lambda(fut) is a minimalist
extension of the call-by-value lambda-calculus that yields
the full expressiveness to define, combine, and implement
a variety of standard concurrency constructs such as channels,
semaphores, and ports. We present a linear type system for
lambda(fut) by which the safety of such definitions
and their combinations can be proved:
Well-typed implementations cannot be corrupted in any well-typed context.
</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.ps.uni-sb.de/Papers/abstracts/cut.html">
<title>Interactive Learning of Node Selecting Tree Transducer</title>
<author>Julien Carme </author>
......@@ -307,19 +286,103 @@ This work is a step towards resolving long-standing open problems of the decidab
<author> Joachim Niehren</author>
<comment>IJCAI Workshop on Grammatical Inference.</comment>
<comment>ML.</comment>
<abstract><p>We present a new learning process for Web information
extraction, that is visually interactive. Web documents are
considered as trees in which wrappers select sets of nodes.
We start from a recent algorithm that induces node selection
queries in trees by
methods of grammatical inference. We then show how to turn this
algorithm into our visually interactive learning process, using
intelligent tree pruning heuristics. Experiments on realistic Web
documents confirm excellent quality with very few user
interactions -- annotations and corrections -- during wrapper induction.
</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.ps.uni-sb.de/Papers/abstracts/wellnested-cu.bib">
<title>Well-nested Context Unification</title>
<author>Jordi Levy </author>
<author> Joachim Niehren </author>
<author> Mateu Villaret</author>
<comment>20th International Conference on Automated Deduction.</comment>
<abstract><p>
We present a new learning process for Web information
extraction, that is visually interactive. Web documents are
considered as trees in which wrappers select sets of nodes.
We start from a recent algorithm that induces node selection
queries in trees by
methods of grammatical inference. We then show how to turn this
algorithm into our visually interactive learning process, using
intelligent tree pruning heuristics. Experiments on realistic Web
documents confirm excellent quality with very few user
interactions -- annotations and corrections -- during wrapper induction.
Context unification (CU) is the famous open problem of
solving context equations for trees. We distinguish
a new decidable fragment of CU - well-nested CU -
and present a new unification algorithm that solves
well-nested context equations in non-deterministic
polynomial time. We show that minimal
well-nested solutions of context equations can be
composed from the material present in the equation.
This surprising property is highly wishful when
modeling natural language ellipsis in CU.
</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.ps.uni-sb.de/Papers/paper_info.php?label=n-ary-query">
<title>N-ary Queries by Tree Automata </title>
<author>Joachim Niehren</author>
<author>Laurent Planque</author>
<author>Jean-Marc Talbot</author>
<author>Sophie Tison</author>
<comment>10th International Symposium on Database Programming Languages.</comment>
<abstract><p>We investigate n-ary node selection queries in trees
by successful runs of tree automata. We show
that run-based n-ary queries capture MSO, contribute
algorithms for enumerating answers of n-ary queries,
and study the complexity of the problem. We investigate
the subclass of run-based n-ary queries by unambiguous
tree automata.
Keywords: XML, databases, information extraction, logic, automata,
types, pattern.
</p></abstract>
</paper>
</li>
<li>
<paper file="http://www.ps.uni-sb.de/Papers/abstracts/mini.html">
<title>Minimizing Tree Automata for Unranked Trees</title>
<author>Wim Martens</author>
<author>Joachim Niehren</author>
<comment>10th International Symposium on Database Programming Languages.</comment>
<abstract><p>Automata for unranked trees form a foundation for XML schemas,
querying and pattern languages. We study the problem of efficiently
minimizing such automata. We start with the unranked tree automata
(UTAs) that are standard in database theory, assuming bottom-up
determinism and that horizontal recursion is represented by
deterministic finite automata. We show that minimal
UTAs in that class are not unique and that minimization
is NP-hard. We then study more recent automata classes that do allow for
polynomial time minimization. Among those, we show that bottom-up
deterministic stepwise tree automata yield the most succinct
representations.
</p></abstract>
</paper>
......
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