29 Search Results for "Wijsen, Jef"

Volume

LIPIcs, Volume 90

24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

TIME 2017, October 16-18, 2017, Mons, Belgium

Editors: Sven Schewe, Thomas Schneider, and Jef Wijsen

Document
DOI: 10.4230/LIPIcs.ICDT.2023.23
Consistent Query Answering for Primary Keys and Conjunctive Queries with Counting

Authors: Aziz Amezian El Khalfioui and Jef Wijsen

Published in: LIPIcs, Volume 255, 26th International Conference on Database Theory (ICDT 2023)

Abstract
The problem of consistent query answering for primary keys and self-join-free conjunctive queries has been intensively studied in recent years and is by now well understood. In this paper, we study an extension of this problem with counting. The queries we consider count how many times each value occurs in a designated (possibly composite) column of an answer to a full conjunctive query. In a setting of database repairs, we adopt the semantics of [Arenas et al., ICDT 2001] which computes tight lower and upper bounds on these counts, where the bounds are taken over all repairs. Ariel Fuxman defined in his PhD thesis a syntactic class of queries, called Cforest, for which this computation can be done by executing two first-order queries (one for lower bounds, and one for upper bounds) followed by simple counting steps. We use the term "parsimonious counting" for this computation. A natural question is whether Cforest contains all self-join-free conjunctive queries that admit parsimonious counting. We answer this question negatively. We define a new syntactic class of queries, called Cparsimony, and prove that it contains all (and only) self-join-free conjunctive queries that admit parsimonious counting.
Cite as

Aziz Amezian El Khalfioui and Jef Wijsen. Consistent Query Answering for Primary Keys and Conjunctive Queries with Counting. In 26th International Conference on Database Theory (ICDT 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 255, pp. 23:1-23:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)

Copy BibTex To Clipboard

@InProceedings{amezianelkhalfioui_et_al:LIPIcs.ICDT.2023.23,
  author =	{Amezian El Khalfioui, Aziz and Wijsen, Jef},
  title =	{{Consistent Query Answering for Primary Keys and Conjunctive Queries with Counting}},
  booktitle =	{26th International Conference on Database Theory (ICDT 2023)},
  pages =	{23:1--23:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-270-9},
  ISSN =	{1868-8969},
  year =	{2023},
  volume =	{255},
  editor =	{Geerts, Floris and Vandevoort, Brecht},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.ICDT.2023.23},
  URN =		{urn:nbn:de:0030-drops-177659},
  doi =		{10.4230/LIPIcs.ICDT.2023.23},
  annote =	{Keywords: Consistent query answering, primary key, conjunctive query, aggregation, counting}
}
Document
DOI: 10.4230/LIPIcs.ICDT.2019.23
Consistent Query Answering for Primary Keys in Logspace

Authors: Paraschos Koutris and Jef Wijsen

Published in: LIPIcs, Volume 127, 22nd International Conference on Database Theory (ICDT 2019)

Abstract
We study the complexity of consistent query answering on databases that may violate primary key constraints. A repair of such a database is any consistent database that can be obtained by deleting a minimal set of tuples. For every Boolean query q, CERTAINTY(q) is the problem that takes a database as input and asks whether q evaluates to true on every repair. In [Koutris and Wijsen, ACM TODS, 2017], the authors show that for every self-join-free Boolean conjunctive query q, the problem CERTAINTY(q) is either in P or coNP-complete, and it is decidable which of the two cases applies. In this paper, we sharpen this result by showing that for every self-join-free Boolean conjunctive query q, the problem CERTAINTY(q) is either expressible in symmetric stratified Datalog (with some aggregation operator) or coNP-complete. Since symmetric stratified Datalog is in L, we thus obtain a complexity-theoretic dichotomy between L and coNP-complete. Another new finding of practical importance is that CERTAINTY(q) is on the logspace side of the dichotomy for queries q where all join conditions express foreign-to-primary key matches, which is undoubtedly the most common type of join condition.
Cite as

Paraschos Koutris and Jef Wijsen. Consistent Query Answering for Primary Keys in Logspace. In 22nd International Conference on Database Theory (ICDT 2019). Leibniz International Proceedings in Informatics (LIPIcs), Volume 127, pp. 23:1-23:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2019)

Copy BibTex To Clipboard

@InProceedings{koutris_et_al:LIPIcs.ICDT.2019.23,
  author =	{Koutris, Paraschos and Wijsen, Jef},
  title =	{{Consistent Query Answering for Primary Keys in Logspace}},
  booktitle =	{22nd International Conference on Database Theory (ICDT 2019)},
  pages =	{23:1--23:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-101-6},
  ISSN =	{1868-8969},
  year =	{2019},
  volume =	{127},
  editor =	{Barcelo, Pablo and Calautti, Marco},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.ICDT.2019.23},
  URN =		{urn:nbn:de:0030-drops-103252},
  doi =		{10.4230/LIPIcs.ICDT.2019.23},
  annote =	{Keywords: conjunctive queries, consistent query answering, Datalog, primary keys}
}
Document
Complete Volume
DOI: 10.4230/LIPIcs.TIME.2017
LIPIcs, Volume 90, TIME'17, Complete Volume

Authors: Sven Schewe, Thomas Schneider, and Jef Wijsen

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
LIPIcs, Volume 90, TIME'17, Complete Volume
Cite as

24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@Proceedings{schewe_et_al:LIPIcs.TIME.2017,
  title =	{{LIPIcs, Volume 90, TIME'17, Complete Volume}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017},
  URN =		{urn:nbn:de:0030-drops-80233},
  doi =		{10.4230/LIPIcs.TIME.2017},
  annote =	{Keywords: Distributed Systems, Design Tools and Techniques, Software/Program Verification, Security and Protection, Models of Computation, Specifying and Verifying and Reasoning about Programs, Mathematical Logic, \lbrackNumerical Linear Algebra\rbrack Linear Systems, Graph Theory}
}
Document
Front Matter
DOI: 10.4230/LIPIcs.TIME.2017.0
Front Matter, Table of Contents, Preface, Organization, List of Authors

Authors: Sven Schewe, Thomas Schneider, and Jef Wijsen

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
Front Matter, Table of Contents, Preface, Organization, List of Authors
Cite as

24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 0:i-0:xiv, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{schewe_et_al:LIPIcs.TIME.2017.0,
  author =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  title =	{{Front Matter, Table of Contents, Preface, Organization, List of Authors}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{0:i--0:xiv},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.0},
  URN =		{urn:nbn:de:0030-drops-79117},
  doi =		{10.4230/LIPIcs.TIME.2017.0},
  annote =	{Keywords: Front Matter, Table of Contents, Preface, Organization, List of Authors}
}
Document
Invited Talk
DOI: 10.4230/LIPIcs.TIME.2017.1
Ontology-Mediated Query Answering over Temporal Data: A Survey (Invited Talk)

Authors: Alessandro Artale, Roman Kontchakov, Alisa Kovtunova, Vladislav Ryzhikov, Frank Wolter, and Michael Zakharyaschev

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
We discuss the use of various temporal knowledge representation formalisms for ontology-mediated query answering over temporal data. In particular, we analyse ontology and query languages based on the linear temporal logic LTL, the multi-dimensional Halpern-Shoham interval temporal logic HS_n, as well as the metric temporal logic MTL. Our main focus is on the data complexity of answering temporal ontology-mediated queries and their rewritability into standard first-order and datalog queries.
Cite as

Alessandro Artale, Roman Kontchakov, Alisa Kovtunova, Vladislav Ryzhikov, Frank Wolter, and Michael Zakharyaschev. Ontology-Mediated Query Answering over Temporal Data: A Survey (Invited Talk). In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 1:1-1:37, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{artale_et_al:LIPIcs.TIME.2017.1,
  author =	{Artale, Alessandro and Kontchakov, Roman and Kovtunova, Alisa and Ryzhikov, Vladislav and Wolter, Frank and Zakharyaschev, Michael},
  title =	{{Ontology-Mediated Query Answering over Temporal Data: A Survey}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{1:1--1:37},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.1},
  URN =		{urn:nbn:de:0030-drops-79338},
  doi =		{10.4230/LIPIcs.TIME.2017.1},
  annote =	{Keywords: Description Logic, Temporal Logic, Ontology Mediated Query Answering, Data Complexity}
}
Document
Invited Talk
DOI: 10.4230/LIPIcs.TIME.2017.2
Advances in Quantitative Analysis of Free-Choice Workflow Petri Nets (Invited Talk)

Authors: Javier Esparza

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
We survey recent results on the development of efficient algorithms for the quantitative analysis of business processes modeled as workflow Petri nets. The algorithms can be applied to any workflow net, but have polynomial runtime in the free-choice case.
Cite as

Javier Esparza. Advances in Quantitative Analysis of Free-Choice Workflow Petri Nets (Invited Talk). In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 2:1-2:6, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{esparza:LIPIcs.TIME.2017.2,
  author =	{Esparza, Javier},
  title =	{{Advances in Quantitative Analysis of Free-Choice Workflow Petri Nets}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{2:1--2:6},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.2},
  URN =		{urn:nbn:de:0030-drops-79266},
  doi =		{10.4230/LIPIcs.TIME.2017.2},
  annote =	{Keywords: Free-choice Petri Nets, concurrency theory, quantitative verification}
}
Document
Invited Talk
DOI: 10.4230/LIPIcs.TIME.2017.3
Plan and Program Synthesis: A New Look at Some Old Problems (Invited Talk)

Authors: Sheila A. McIlraith

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
The proliferation of programmable devices, personal assistants, and autonomous systems presents fundamental challenges to the deployment of safe, predictable systems that can work together, interact seamlessly with humans, and that are taskable and instructable by people who may not know how to program. In this talk, we will revisit the classical problem of program synthesis through the lens of AI automated planning. We will present recent advances in AI automated planning principles and computational methods that support the synthesis of plans with goals and preferences specified in Linear Temporal Logic and Regular Expressions. Moving from automated planning in deterministic domains to planning in nondeterministic domains, we will explore the pathway to synthesizing programs that are taskable and instructable by exploiting state-of-the-art AI planning technology.
Cite as

Sheila A. McIlraith. Plan and Program Synthesis: A New Look at Some Old Problems (Invited Talk). In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, p. 3:1, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{mcilraith:LIPIcs.TIME.2017.3,
  author =	{McIlraith, Sheila A.},
  title =	{{Plan and Program Synthesis: A New Look at Some Old Problems}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{3:1--3:1},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.3},
  URN =		{urn:nbn:de:0030-drops-79343},
  doi =		{10.4230/LIPIcs.TIME.2017.3},
  annote =	{Keywords: planning, program synthesis, linear temporal logic, regular expressions}
}
Document
DOI: 10.4230/LIPIcs.TIME.2017.4
Possible and Certain Answers for Queries over Order-Incomplete Data

Authors: Antoine Amarilli, Mouhamadou Lamine Ba, Daniel Deutch, and Pierre Senellart

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
To combine and query ordered data from multiple sources, one needs to handle uncertainty about the possible orderings. Examples of such "order-incomplete" data include integrated event sequences such as log entries; lists of properties (e.g., hotels and restaurants) ranked by an unknown function reflecting relevance or customer ratings; and documents edited concurrently with an uncertain order on edits. This paper introduces a query language for order-incomplete data, based on the positive relational algebra with order-aware accumulation. We use partial orders to represent order-incomplete data, and study possible and certain answers for queries in this context. We show that these problems are respectively NP-complete and coNP-complete, but identify many tractable cases depending on the query operators or input partial orders.
Cite as

Antoine Amarilli, Mouhamadou Lamine Ba, Daniel Deutch, and Pierre Senellart. Possible and Certain Answers for Queries over Order-Incomplete Data. In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 4:1-4:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{amarilli_et_al:LIPIcs.TIME.2017.4,
  author =	{Amarilli, Antoine and Ba, Mouhamadou Lamine and Deutch, Daniel and Senellart, Pierre},
  title =	{{Possible and Certain Answers for Queries over Order-Incomplete Data}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{4:1--4:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.4},
  URN =		{urn:nbn:de:0030-drops-79311},
  doi =		{10.4230/LIPIcs.TIME.2017.4},
  annote =	{Keywords: certain answer, possible answer, partial order, uncertain data}
}
Document
DOI: 10.4230/LIPIcs.TIME.2017.5
Constraint Identification Using Modified Hoare Logic on Hybrid Models of Gene Networks

Authors: Jonathan Behaegel, Jean-Paul Comet, and Maxime Folschette

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
We present a new hybrid Hoare logic dedicated for a class of linear hybrid automata well suited to model gene regulatory networks. These automata rely on Thomas' discrete framework in which qualitative parameters have been replaced by continuous parameters called celerities. The identification of these parameters remains one of the keypoints of the modelling process, and is difficult especially because the modelling framework is based on a continuous time. We introduce Hoare triples which handle biological traces and pre/post-conditions. Observed chronometrical biological traces play the role of an imperative program for classical Hoare logic and our hybrid Hoare logic, defined by inference rules, is proved to be sound. Furthermore, we present a weakest precondition calculus (a la Dijkstra) which leads to constraints on dynamical parameters. Finally, we illustrate our "constraints generator" with a simplified circadian clock model describing the rhythmicity of cells in mammals on a 24-hour period.
Cite as

Jonathan Behaegel, Jean-Paul Comet, and Maxime Folschette. Constraint Identification Using Modified Hoare Logic on Hybrid Models of Gene Networks. In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 5:1-5:21, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{behaegel_et_al:LIPIcs.TIME.2017.5,
  author =	{Behaegel, Jonathan and Comet, Jean-Paul and Folschette, Maxime},
  title =	{{Constraint Identification Using Modified Hoare Logic on Hybrid Models of Gene Networks}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{5:1--5:21},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.5},
  URN =		{urn:nbn:de:0030-drops-79203},
  doi =		{10.4230/LIPIcs.TIME.2017.5},
  annote =	{Keywords: Hoare logic, weakest precondition, linear hybrid automata, constraint synthesis, gene networks}
}
Document
DOI: 10.4230/LIPIcs.TIME.2017.6
Hierarchical Cost-Parity Games

Authors: Laura Bozzelli, Aniello Murano, Giuseppe Perelli, and Loredana Sorrentino

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
Cost-parity games are a fundamental tool in system design for the analysis of reactive and distributed systems that recently have received a lot of attention from the formal methods research community. They allow to reason about the time delay on the requests granted by systems, with a bounded consumption of resources, in their executions. In this paper, we contribute to research on Cost-parity games by combining them with hierarchical systems, a successful method for the succinct representation of models. We show that determining the winner of a Hierarchical Cost-parity Game is PSpace-Complete, thus matching the complexity of the proper special case of Hierarchical Parity Games. This shows that reasoning about temporal delay can be addressed at a free cost in terms of complexity.
Cite as

Laura Bozzelli, Aniello Murano, Giuseppe Perelli, and Loredana Sorrentino. Hierarchical Cost-Parity Games. In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 6:1-6:17, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{bozzelli_et_al:LIPIcs.TIME.2017.6,
  author =	{Bozzelli, Laura and Murano, Aniello and Perelli, Giuseppe and Sorrentino, Loredana},
  title =	{{Hierarchical Cost-Parity Games}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{6:1--6:17},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.6},
  URN =		{urn:nbn:de:0030-drops-79175},
  doi =		{10.4230/LIPIcs.TIME.2017.6},
  annote =	{Keywords: Parity Games, Cost-Parity Games, Hierarchical Systems, System Verification}
}
Document
DOI: 10.4230/LIPIcs.TIME.2017.7
Timed-Automata-Based Verification of MITL over Signals

Authors: Thomas Brihaye, Gilles Geeraerts, Hsi-Ming Ho, and Benjamin Monmege

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
It has been argued that the most suitable semantic model for real-time formalisms is the non-negative real line (signals), i.e. the continuous semantics, which naturally captures the continuous evolution of system states. Existing tools like UPPAAL are, however, based on omega-sequences with timestamps (timed words), i.e. the pointwise semantics. Furthermore, the support for logic formalisms is very limited in these tools. In this article, we amend these issues by a compositional translation from Metric Temporal Interval Logic (MITL) to signal automata. Combined with an emptiness-preserving encoding of signal automata into timed automata, we obtain a practical automata-based approach to MITL model-checking over signals. We implement the translation in our tool MightyL and report on case studies using LTSmin as the back-end.
Cite as

Thomas Brihaye, Gilles Geeraerts, Hsi-Ming Ho, and Benjamin Monmege. Timed-Automata-Based Verification of MITL over Signals. In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 7:1-7:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{brihaye_et_al:LIPIcs.TIME.2017.7,
  author =	{Brihaye, Thomas and Geeraerts, Gilles and Ho, Hsi-Ming and Monmege, Benjamin},
  title =	{{Timed-Automata-Based Verification of MITL over Signals}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{7:1--7:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.7},
  URN =		{urn:nbn:de:0030-drops-79126},
  doi =		{10.4230/LIPIcs.TIME.2017.7},
  annote =	{Keywords: real-time temporal logic, timed automata, real-time systems}
}
Document
DOI: 10.4230/LIPIcs.TIME.2017.8
Dynamic Controllability Made Simple

Authors: Massimo Cairo and Romeo Rizzi

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
Simple Temporal Networks with Uncertainty (STNUs) are a well-studied model for representing temporal constraints, where some intervals (contingent links) have an unknown but bounded duration, discovered only during execution. An STNU is dynamically controllable (DC) if there exists a strategy to execute its time-points satisfying all the constraints, regardless of the actual duration of contingent links revealed during execution. In this work we present a new system of constraint propagation rules for STNUs, which is sound-and-complete for DC checking. Our system comprises just three rules which, differently from the ones proposed in all previous works, only generate unconditioned constraints. In particular, after applying our sound rules, the network remains an STNU in all respects. Moreover, our completeness proof is short and non-algorithmic, based on the explicit construction of a valid execution strategy. This is a substantial simplification of the theory which underlies all the polynomial-time algorithms for DC-checking. Our analysis also shows: (1) the existence of late execution strategies for STNUs, (2) the equivalence of several variants of the notion of DC, (3) the existence of a fast algorithm for real-time execution of STNUs, which runs in O(KN) total time in a network with K contingent links and N time points, considerably improving the previous O(N^3)-time bound.
Cite as

Massimo Cairo and Romeo Rizzi. Dynamic Controllability Made Simple. In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 8:1-8:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{cairo_et_al:LIPIcs.TIME.2017.8,
  author =	{Cairo, Massimo and Rizzi, Romeo},
  title =	{{Dynamic Controllability Made Simple}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{8:1--8:16},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.8},
  URN =		{urn:nbn:de:0030-drops-79136},
  doi =		{10.4230/LIPIcs.TIME.2017.8},
  annote =	{Keywords: Simple Temporal Network with Uncertainty, Dynamic controllability}
}
Document
DOI: 10.4230/LIPIcs.TIME.2017.9
Incorporating Decision Nodes into Conditional Simple Temporal Networks

Authors: Massimo Cairo, Carlo Combi, Carlo Comin, Luke Hunsberger, Roberto Posenato, Romeo Rizzi, and Matteo Zavatteri

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
A Conditional Simple Temporal Network (CSTN) augments a Simple Temporal Network (STN) to include special time-points, called observation time-points. In a CSTN, the agent executing the network controls the execution of every time-point. However, each observation time-point has a unique propositional letter associated with it and, when the agent executes that time-point, the environment assigns a truth value to the corresponding letter. Thus, the agent observes but, does not control the assignment of truth values. A CSTN is dynamically consistent (DC) if there exists a strategy for executing its time-points such that all relevant constraints will be satisfied no matter which truth values the environment assigns to the propositional letters. Alternatively, in a Labeled Simple Temporal Network (Labeled STN) - also called a Temporal Plan with Choice - the agent executing the network controls the assignment of values to the so-called choice variables. Furthermore, the agent can make those assignments at any time. For this reason, a Labeled STN is equivalent to a Disjunctive Temporal Network. This paper incorporates both of the above extensions by augmenting a CSTN to include not only observation time-points but also decision time-points. A decision time-point is like an observation time-point in that it has an associated propositional letter whose value is determined when the decision time-point is executed. It differs in that the agent - not the environment - selects that value. The resulting network is called a CSTN with Decisions (CSTND). This paper shows that a CSTND generalizes both CSTNs and Labeled STNs, and proves that the problem of determining whether any given CSTND is dynamically consistent is PSPACE-complete. It also presents algorithms that address two sub-classes of CSTNDs: (1) those that contain only decision time-points; and (2) those in which all decisions are made before execution begins.
Cite as

Massimo Cairo, Carlo Combi, Carlo Comin, Luke Hunsberger, Roberto Posenato, Romeo Rizzi, and Matteo Zavatteri. Incorporating Decision Nodes into Conditional Simple Temporal Networks. In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 9:1-9:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{cairo_et_al:LIPIcs.TIME.2017.9,
  author =	{Cairo, Massimo and Combi, Carlo and Comin, Carlo and Hunsberger, Luke and Posenato, Roberto and Rizzi, Romeo and Zavatteri, Matteo},
  title =	{{Incorporating Decision Nodes into Conditional Simple Temporal Networks}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{9:1--9:18},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.9},
  URN =		{urn:nbn:de:0030-drops-79155},
  doi =		{10.4230/LIPIcs.TIME.2017.9},
  annote =	{Keywords: Conditional Simple Temporal Networks with Decisions, Dynamic Consistency, SAT Solver, Hyper Temporal Networks, PSPACE}
}
Document
DOI: 10.4230/LIPIcs.TIME.2017.10
A Streamlined Model of Conditional Simple Temporal Networks - Semantics and Equivalence Results

Authors: Massimo Cairo, Luke Hunsberger, Roberto Posenato, and Romeo Rizzi

Published in: LIPIcs, Volume 90, 24th International Symposium on Temporal Representation and Reasoning (TIME 2017)

Abstract
A Conditional Simple Temporal Network (CSTN) augments a Simple Temporal Network to include a new kind of time-points, called observation time-points. The execution of an observation time-point generates information in real time, specifically, the truth value of a propositional letter. In addition, time-points and temporal constraints may be labeled by conjunctions of (positive or negative) propositional letters. A CSTN is called dynamically consistent (DC) if there exists a dynamic strategy for executing its time-points such that no matter how the observations turn out during execution, the time-points whose labels are consistent with those observations have all been executed, and the constraints whose labels are consistent with those observations have all been satisfied. The strategy is dynamic in that its execution decisions may react to observations. The original formulation of CSTNs included propositional labels only on time-points, but the DC-checking algorithm was impractical because it was based on a conversion of the semantic constraints into an exponentially-sized Disjunctive Temporal Network. Later work added propositional labels to temporal constraints, and yielded a sound-and-complete propagation-based DC-checking algorithm, empirically demonstrated to be practical across a variety of CSTNs. This paper introduces a streamlined version of a CSTN in which propositional labels may appear on constraints, but not on time-points. This change simplifies the definition of the DC property, as well as the propagation rules for the DC-checking algorithm. It also simplifies the proofs of the soundness and completeness of those rules. This paper provides two translations from traditional CSTNs to streamlined CSTNs. Each translation preserves the DC property and, for any DC network, ensures that any dynamic execution strategy for that network can be extended to a strategy for its streamlined counterpart. Finally, this paper presents an empirical comparison of two versions of the DC-checking algorithm: the original version and a simplified version for streamlined CSTNs. The comparison is based on CSTN benchmarks from earlier work. For small-sized CSTNs, the original version shows the best performance, but the performance difference between the two versions decreases as the number of time-points in the CSTN increases. We conclude that the simplified algorithm is a practical alternative for checking the dynamic consistency of CSTNs.
Cite as

Massimo Cairo, Luke Hunsberger, Roberto Posenato, and Romeo Rizzi. A Streamlined Model of Conditional Simple Temporal Networks - Semantics and Equivalence Results. In 24th International Symposium on Temporal Representation and Reasoning (TIME 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 90, pp. 10:1-10:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)

Copy BibTex To Clipboard

@InProceedings{cairo_et_al:LIPIcs.TIME.2017.10,
  author =	{Cairo, Massimo and Hunsberger, Luke and Posenato, Roberto and Rizzi, Romeo},
  title =	{{A Streamlined Model of Conditional Simple Temporal Networks - Semantics and Equivalence Results}},
  booktitle =	{24th International Symposium on Temporal Representation and Reasoning (TIME 2017)},
  pages =	{10:1--10:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-052-1},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{90},
  editor =	{Schewe, Sven and Schneider, Thomas and Wijsen, Jef},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.TIME.2017.10},
  URN =		{urn:nbn:de:0030-drops-79145},
  doi =		{10.4230/LIPIcs.TIME.2017.10},
  annote =	{Keywords: Conditional Simple Temporal Networks, Dynamic Consistency, Temporal Constraints}
}
  • Refine by Author
  • 5 Wijsen, Jef
  • 3 Cairo, Massimo
  • 3 Rizzi, Romeo
  • 2 Geeraerts, Gilles
  • 2 Hunsberger, Luke
  • Show More...

  • Refine by Classification
  • 1 Information systems → Incomplete data
  • 1 Information systems → Inconsistent data
  • 1 Information systems → Integrity checking
  • 1 Information systems → Relational database model
  • 1 Information systems → Relational database query languages
  • Show More...

  • Refine by Keyword
  • 2 Dynamic Consistency
  • 2 Temporal Logic
  • 1 Access Control
  • 1 Algorithms
  • 1 Archaeology
  • Show More...

  • Refine by Type
  • 28 document
  • 1 volume

  • Refine by Publication Year
  • 26 2017
  • 1 2009
  • 1 2019
  • 1 2023

Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail
© 2023-2024 Schloss Dagstuhl – LZI GmbH Imprint Privacy Contact