Pedro Cabalar

Associate Professor

Department of Computer Science
Corunna University,
Galicia, Spain

Short bio.
Teaching
Research
Publications


Facultade de Informática,
Campus de Elviña S/N
E-15071, A Coruña, Spain.

Tel.:   +34 881011265
Fax:    +34 981 167160
e-mail: 
 


Short Bio.

Born in Cabanas, Corunna, on 20th of July of 1969 (Neil Amstrong was very busy that day...). Some facts, in reverse chronological order:

Research


I'm currently interested in the following areas related to Artificial Intelligence, and especially to Knowledge Representation:
  • Knowledge Representation, Reasoning about Actions and Change
    Work in this field is mostly oriented to the design and development of action theories and languages (see Functional Action Language, FAL). Other topics of interest include the study of theoretical foundations of causality or the application to spatio-temporal reasoning. Some links and incoming events:
  • Logic Programming (LP) and Nonmonotonic Reasoning (NMR)
    both theoretical foundantions and practical applications. I'm interested in the three well-known LP semantics of stable models, well-founded semantics and Clark's completion, and their application as NMR frameworks for actions reasoning. In the theoretical field, I'm mostly concerned with logical interpretations of general NMR (LP, Default Logic, Modal nonmonotonic logics, etc) and especially in the logical characterisation of stable models: Equilibrium Logic. Several related links and events:

  • Applied logics
    my research on the two topics above relies on applications of modal, temporal, multi-valued, intuitionistic and conditional logics, always under the perspective of their use for NMR.

Research projects:

  • MERLOT: MEdical Reasoning with LOgical Tools
    TIN2013-42149-P, Spanish Ministry of Economy and Competitivity (MINECO) January 2014 - December 2016.
  • FEAST: Foundations and Extensions of Answer Set Programming Technology
    TIN2009-14562-C05-04, Spanish Ministry of Science and Innovation (MICINN) inside a coordinated project with other 4 Spanish nodes: University of Málaga, Politechnic Univ. of Madrid, Univ. of Cadiz, and Univ. Rey Juan Carlos, Móstoles. January 2010 - December 2012.

  • Logics, Deduction and Programming for Intelligent Systems: Extensions and Applications of Answer Set Programming
    TIN2006-15455-C03-02, Spanish Ministry of Education and Science (MEC) inside a coordinated project with University of Málaga (Spain), and Univ. Rey Juan Carlos, Móstoles (Spain). October 2006 - October 2009.

  • Genetic Algorithms in Satisfiability Problems: Formal Study and Application to Answer Set Programming
    INCITE08-PXIB105159PR, Xunta de Galicia (Spain). October 2008 - October 2011.

PhD supervising:

  • Martín Diéguez Lodeiro, "Temporal Answer Set Programming." PhD thesis, supervisor: Pedro Cabalar. Computer Science Department, Facultad de Informática, University of Corunna, February 23rd, 2015.
    Dissertation Award 2016 (Universtity of Corunna).

  • Jorge Fandiño García, "A Causal Semantics for Logic Programming." PhD thesis, supervisor: Pedro Cabalar. Computer Science Department, Facultad de Informática, University of Corunna, September 11th, 2015.

Other research activities include:


Publications* by year

* - the electronic versions of the papers included below correspond to preliminary drafts, in a previous stage to their final publication.

Unpublished drafts

F. Aguado, P. Cabalar, M. Diéguez, G. Pérez and C. Vidal "Temporal Equilibrium Logic with Past Operators".

P. Cabalar, D. Pearce and A. Valverde, "Stable Reasoning".

2016


P. Cabalar, C. Pérez and G. Pérez "Equilibrium Graphs," in Proc. of the 9th Intl. Workshop on Answer Set Programming and Other Computing Paradigms (ASPOCP'16),  New York, USA, October 16, 2016 (to appear).

F. Aguado, P. Cabalar, M. Diéguez, G. Pérez and C. Vidal "Temporal Logic Programs with Variables". Theory and Practice of Logic Programming, 2016 (to appear).

P. Cabalar and J. Fandinno "Justifications for Programs with Disjunctive and Causal-choice Rules," in Proc. of the 32nd Intl. Conf. on Logic Programming (ICLP'16), New York, USA, October 16-21, 2016. Theory and Practice of Logic Programming, 2016 (to appear).

P. Cabalar, R. Kaminski, M. Ostrowski and T. Schaub, "An ASP Semantics for Default Reasoning with Constraints," 
International Joint Conference on Artificial Intelligence (IJCAI'16), New York, USA, July 9-15th, 2016.

P. Cabalar and P. E. Santos, "A Qualitative Spatial Representation of String Loops as Holes," 
Artificial Intelligence 238, pp. 1-10, 2016.

P. Cabalar and J. Fandinno, "Enablers and Inhibitors in Causal Justifications of Logic Programs,"
Theory and Practice of Logic Programming, 2016. [extended journal version of LPNMR'15 paper].

P. Santos and P. Cabalar, "Framing Holes within a Loop Hierarchy," Spatial Cognition and Computation 16 (1), 54-95, 2016.


2015

P. Cabalar, "Stable Models for Temporal Theories - Invited Talk," in Proc. of the 13th Intel. Conf. on Logic Programming and Non-Monotonic Reasoning (LPNMR'15), Lecture Notes in Artificial Intelligence LNAI 9345, 2015.

P. Cabalar and J. Fandinno, "Enablers and Inhibitors in Causal Justifications of Logic Programs," in Proc. of the 13th Intel. Conf. on Logic Programming and Non-Monotonic Reasoning (LPNMR'15), Lecture Notes in Artificial Intelligence LNAI 9345, 2015. [One of the 4 best paper awards]

P. Cabalar, M. Diéguez and C. Vidal, "An Infinitary Encoding of Temporal Equilibrium Logic," in Proc. of the 31st Intl. Conf. on Logic Programming (ICLP'15), Cork, Ireland, August 31 - Sept. 4th, 2015. Theory and Practice of Logic Programming 15 (4-5), 666-680, 2015.

F. Aguado, P. Cabalar, D. Pearce, G. Pérez and C. Vidal, "A Denotational Semantics for Equilibrium Logic," in Proc. of the 31st Intl. Conf. on Logic Programming (ICLP'15), Cork, Ireland, August 31 - Sept. 4th, 2015. Theory and Practice of Logic Programming 15 (4-5), 620-634, 2015.

F. Aguado, P. Ascariz, P. Cabalar, G. Pérez and C. Vidal, "Formal Veri fication for ASP: a Case Study using the PVS Theorem Prover," in Proc. of the 15th Intl. Conf. on Computational and Mathematical Methods in Science and Engineering (CMMSE'15), Rota, Cádiz, Spain, July 6-10, 2015.

P. Cabalar and J. Fandinno. "Explaining preferences and preferring explanations," in Advances in Knowledge Representation, Logic Programming, and Abstract Argumentation, Essays Dedicated to Gerhard Brewka on the Occasion of His 60th Birthday. Thomas Eiter, Hannes Strass, Mirosław Truszczyński and Stefan Woltran (eds). Lecture Notes in Computer Science, Volume 9060, 2015.


2014

P. Cabalar, J. Fandinno and M. Fink, "A Complexity Assessment for Queries involving Sufficient and Necessary Causes," in Proc. of the 14th European Conference on Logics in Artificial Intelligence (JELIA'14), Funchal, Madeira, Portugal, September 24th-26th, 2014. Lecture Notes in Artificial Intelligence (8761), pp. 300-310, Springer-Verlag, 2014.

P. Cabalar, L. Fariñas del Cerro, D. Pearce and A. Valverde, "A Free Logic for Stable Models with Partial Intensional Functions," Proc. of the 14th European Conference on Logics in Artificial Intelligence (JELIA'14), Funchal, Madeira, Portugal, September 24th-26th, 2014.
Lecture Notes in Artificial Intelligence (8761), pp. 340-354, Springer-Verlag, 2014.

P. Cabalar, J. Fandinno and M. Fink, "Causal Graph Justifications of Logic Programs," in Proc. of the 30th International Conference on Logic Programming (ICLP'14), July 19-22, 2014, Vienna, Austria (to appear). [extended version]. Theory and Practice of Logic Programming 14 (4-5), 603-618, 2014.

P. Cabalar and M. Diéguez, "Strong Equivalence of Non-Monotonic Temporal Theories," in Proc. of the 14th International Conference on Principles of Knowledge Representation and Reasoning (KR'14), Vienna, Austria. July 20-24, 2014. [extended version].

P. Cabalar and M. Diéguez, "Temporal Stable Models are LTL-representable," in Proc. of the 7th Intl. Workshop on Answer Set Programming and Other Computing Paradigms (ASPOCP'14), Vienna, Austria, July 23rd, 2014. NOTE: the proof in this paper has been later proved to be wrong.

2013


P. Cabalar and J. Fandinno, "An algebra of causal chains," in Proc. of the 6th International Workshop on Answer Set Programming and Other Computing Paradigms (ASPOCP'13), Istambul, Turkey,  2013.

F. Aguado, P. Cabalar, M. Diéguez, G. Pérez, C. Vidal, "Temporal equilibrium logic: a survey." Journal of Applied Non-Classical Logics 23(1-2): 2-24 (2013).

P. E. Santos, P. Cabalar, "An Investigation of Actions, Change and Space." Proceedings of the 23rd International Conference on Automated Planning and Scheduling, ICAPS 2013, Rome, Italy, June 10-14, 2013. (special track for presenting journal papers. It contains a summary of Cabalar & Santos 2011, AIJ).

P. E. Santos and P. Cabalar, "An investigation of actions, change, space within a hole-loop dichotomy" in Proc. of the 11th Intl. Symp. on Logical Formalizations of Commonsense Reasoning, Ayia Napa, Cyprus, 27-29 May 2013.

P. Cabalar, "Setting the Stage for Answer Set Functions," ALP Newsletter, September 2013.

2012


P. E. Santos and P. Cabalar, "Knots World: an investigation of actions, change and space," in: Proceedings of the Spatio-temporal Dynamics Workshop (STeDy'12), Montpellier 2012. p. 36-44 (inside ECAI 2012).

F. Aguado, P. Cabalar, M. Diéguez, G. Pérez and C. Vidal, "Paving the Way for Temporal Grounding", in Proc. of the 28th International Conference on Logic Programming (ICLP'12), Budapest, Hungary, September 2012 (to appear).

P. Cabalar, "Causal Logic Programming" (warning: this is a corrected, post-edition version) in Correct Reasoning: Essays on Logic-Based AI in Honour of Vladimir Lifschitz, Esra Erdem, Joohyung Lee, Yuliya Lierler and David Pearce (eds.), pp. 102-116, Springer, 2012.


2011

P. Cabalar and S. Demri, "Automata-based Computation of Temporal Equilibrium Models," in 21st International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR'11), Odense, Denmark, 2011.

P. Cabalar, "Answer Set; Programming?" in Logic Programming, Knowledge Representation and Nonmonotonic Reasoning: essays dedicated to Michael Gelfond on the occasion of his 65th birthday, Marcello Balduccini and Tran Cao Son (eds), pp. 334-343, Springer, 2011.

P. Cabalar, "A logical Characterisation of Ordered Disjunction" in AI Communications 24, 2, pp. 165-175, 2011.

P. Cabalar, "Functional Answer Set Programming", Theory and Practice of Logic Programming, 11 (2-3), pp. 203-233, 2011.

P. Cabalar and M. Diéguez, "An Experiment on Tabled Evaluation for Hidden Predicates," 1st Workshop on Grounding and Transformations for Theories with Variables (GTTV'11), inside LPNMR'11 Vancouver, BC, Canada, May 16, 2011.

F. Aguado, P. Cabalar, G. Pérez and C. Vidal, "Loop Formulas for Splitable Temporal Logic Programs", 11th International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR'11) Vancouver, BC, Canada, May 16-19, 2011.

P. Cabalar and M. Diéguez, "STeLP - a Tool for Temporal Answer Set Programming".
11th International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR'11) Vancouver, BC, Canada, May 16-19, 2011.

P. Cabalar and P. E. Santos, "Formalising the Fisherman's Folly puzzle", Artificial Intelligence 175(1), pp. 346-377, 2011.
A preliminary draft is available here.


P. Cabalar, "Logic Programs and Causal Proofs", 10th Intl. Symposium on Logical Formalization on Commonsense Reasoning (Commonsense'11), (AAAI Spring Symposium Series) Stanford University (CA) USA, March 21-23, 2011.

2010

P. Cabalar, "A Normal Form for Linear Temporal Equilibrium Logic", 12th European Conference on Logics in Artificial Intelligence (JELIA'10), Helsinki, Finland, September 13-15, 2010. Lecture Notes in Computer Science vol. 6341, pp. 64-76, 2010. (This is a revised post-proceedings version where some typos were corrected).

P. Cabalar, "A Logical Characterisation of Ordered Disjunction", 3rd Workshop on Answer Set Programming and Other Computing Paradigms (ASPOCP'10), Edinburgh, UK, July 20th 2010.


2009

P. Cabalar, "Existential Quantifiers in the Rule Body", 23rd Workshop on (Constraint) Logic Programming (WLP'09), Potsdam, Germany, September 15/16, 2009.

P. Cabalar, D. Pearce and A. Valverde, "Safety Preserving Transformations for General Answer Set Programs", 19th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR'09), Coimbra, Portugal, September 9-11, 2009.

P. Cabalar, D. Pearce and A. Valverde, "A Revised Concept of Safety for General Answer Set Programs", 10th International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR'09), Potsdam, Germany, 14-18 September 2009, Lecture Notes in Artificial Intelligence (5753), pp. 58-70, 2009.

2008

P. Cabalar, "Partial Functions and Equality in Answer Set Programming", 24th International Conference on Logic Programming (ICLP'08), Udine, Italy, December 2008. Lecture Notes in Artificial Intelligence, vol. 5293, pp. 8-20, 2008.

F. Aguado, P. Cabalar, G. Pérez and C. Vidal, "Strongly Equivalent Temporal Logic Programs", 11th European Conference on Logics in Artificial Intelligence (JELIA'08), Dresden, Germany, September 2008, Lecture Notes in Artificial Intelligence (5293), pp. 8-20, 2008.

P. E. Santos and P. Cabalar, "The space within the Fisherman's Folly: playing with a puzzle in mereotopology", Spatial Cognition and Computation 8:47-64, 2008.

Author Posting. (c) 'Taylor & Francis Group, LLC', 2008.
This is the author's version of the work. It is posted here by permission of 'Taylor & Francis Group, LLC' for personal use, not for redistribution.
The definitive version was published in Spatial Cognition & Computation, Volume 8 Issue 1, January 2008.
doi:10.1080/13875860801944804



2007

P. Cabalar, S. Odintsov, D. Pearce and A. Valverde, "Partial Equilibrium Logic", Annals of Mathematics and Artificial Intelligence (50), pp. 305-331, 2007.

P. Cabalar, D. Pearce and A. Valverde, "Minimal Logic Programs", 23rd International Conference on Logic Programming (ICLP'07), Porto, Portugal, September 2007.
Lecture Notes in Computer Science (4670), pp. 104-118, 2007.
An extended version of this paper including proofs of theorems is available here (with some minor typos corrected).
Program available minlp.pl . It's written for SWI-Prolog interpreter and can be simply executed from the command line by typing
$ swipl -q -f minlp.pl
For further help call predicate help(minlp).
This program has been used to generate the list of 162 possible (minimal) logic programs for 2 variables.

P. Cabalar and G. P. Vega, "Temporal Equilibrium Logic: a first approach", 11th International Conference on Computer Aided Systems Theory, (EUROCAST'07), Las Palmas de Gran Canaria, Spain, February 2007. Lecture Notes in Computer Science (4739), pp. 241-248, 2007.

P. Cabalar, D. Pearce, P. Rondogianis and W. Wadge, "A Purely Model-Theoretic Semantics for Disjunctive Logic Programs with Negation", 9th International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR'07), Tempe, AZ. May 14-17 2007, Lecture Notes in Artificial Intelligence (4483), pp- 44-57, 2007.

P. E. Santos and P. Cabalar, "Holes, Knots and Shapes: A Spatial Ontology of a Puzzle", 8th International Symposium on Logical Formalizations of Commonsense Reasoning (Commonsense'07), inside the AAAI Spring Symposium Series 2007, Stanford, CA, USA, March 2007.

P. Cabalar and P. Ferraris, "Propositional Theories are Strongly Equivalent to Logic Programs", Theory and Practice of Logic Programming 7 (6), pp. 745-759, 2007.

2006

P. Cabalar, S. Odintsov, D. Pearce and A. Valverde, "On the Logic and Computation of Partial Equilibrium Models", 10th European Conference on Logics in Artificial Intelligence (JELIA'06), Lecture Notes in Artificial Intelligence (4160), pp. 82-94, 2006.
An extended version of this paper including proofs of theorems is available here.

P. Santos and P. Cabalar, "Passing through Holes and Getting Entangled by Strings: An Automated Solution for a Spatial Puzzle", Workshop on Spatial and Temporal Reasoning, (inside the European Conference on Artificial Intelligence, ECAI'06), Riva del Garda, Italy, August 2006.

P. Cabalar and P. Santos, "Strings and holes: an exercise on spatial representation and reasoning"
, Proceedings of the 10th Ibero-American Artificial Intelligence Conference (IBERAMIA'06), Ribeirão Preto, Brazil, Lecture Notes in Artificial Intelligence (4140), pp. 419-429, October 2006.

P. Cabalar, S. Odintsov and D. Pearce, "Strong Negation in Well-Founded and Partial Stable Semantics for Logic Programs", Proceedings of the 10th Ibero-American Artificial Intelligence Conference (IBERAMIA'06), Ribeirão Preto, Brazil, Lecture Notes in Artificial Intelligence (4140), pp. 592-601, October 2006. [PDF slides 805K]

P. Cabalar, S. Odintsov, D. Pearce and A. Valverde, "Analysing and Extending Well-Founded and Partial Stable Semantics using Partial Equilibrium Logic
", Proceedings of the International Conference on Logic Programming (ICLP'06), Lecture Notes in Computer Science (4079), pp. 346-360, Seattle, USA, August 2006. [PDF slides 560K]

P. Cabalar, S. Odintsov and D. Pearce, "Logical Foundations of Well-Founded Semantics", Proceedings of the 10th International Conference on Principles of Knowledge Representation and Reasoning (KR'06), Lake District, UK, June 2006 [PDF slides 670K].

2005

P. Cabalar, S. Odintsov and D. Pearce, "A Logic for Reasoning about Well-Founded Semantics: Preliminary Report", proceedings of the 11th Conference of the Spanish for AI (CAEPIA'05), pp. 183-192, Santiago de Compostela, Spain, 2005.

P. Cabalar, D. Pearce and A. Valverde, "Reducing Propositional Theories in Equilibrium Logic to Logic Programs", 12th Portuguese Conference on Artificial Intelligence (EPIA'05). Lecture Notes in Computer Science 3808, pp. 4-17, 2005.

P. Cabalar, "A Functional Action Language Front-end", presentation at the 3rd Workshop on Answer Set Programming (ASP'05), Bath, UK, July 2005. [link to FAL page]

2004

P. Cabalar and D. Lorenzo, "Logic Programs with Functions and Default Values," 9th European Conference on Logics in Artificial Intelligence (JELIA'04), Lisbon, Portugal, September 2004. Lecture Notes in Artificial Intelligence 3229, pp. 294-306.
A preliminary report was presented at the Workshop on Applications of Logic and Mathematics to Programming, 2nd Altea International Seminars, Altea, Spain, October 2003.

P. Cabalar and D. Lorenzo, "New insights on the intuitionistic interpretation of Default Logic," Proceedings of the 16th European Conference on Artificial Intelligence (ECAI'04), pp. 798-802, Valencia, Spain, August 2004. An online extended report contains the proofs for the main results.

2003

P. Cabalar, "A Preliminary Study on Reasoning about Causes," 6th Intl. Symposium on Logical Formalizations of Commonsense Reasoning, inside the AAAI 2003 Spring Symposium Series, Stanford, Palo Alto, USA, March 2003. [Powerpoint slides 189K]

2002

P. Cabalar, "A rewriting method for Well-Founded semantics with explicit negation," International Conference on Logic Programming (ICLP'02), Copenhagen, Denmark, July 2002, Lecture Notes in Computer Science (2401): 378-392, 2002. [Powerpoint slides 160K]

P. Cabalar, "A Three-valued characterization for strong equivalence of logic programs," 18th National Conference on Artificial Intelligence (AAAI'02),  Edmonton, Canada, July 2002.  (Extended version published at NMR'02; see below).

P. Cabalar, "Alternative characterizations for strong equivalence of logic programs," 9th Intl. Workshop on Non-monotonic Reasoning (NMR'02),  Toulouse, France, April 2002.


2001

P. Cabalar, "Pertinence for Causal Representation of Action Domains," PhD dissertation, Computer Science Dept., University of Corunna, december 2001. [Presentation slides 137K]

P. Cabalar, "Well Founded Semantics as Two-dimensional Here-and-There," Proceedings of the Workshop on Answer Set Programming, ASP 2001, (AAAI Press, technical report SS-01-01), inside the 2001 AAAI Spring Symposium Series, Stanford, 26-28 March 2001.

2000

P. Cabalar, R. P. Otero, S. G. Pose, "Temporal Constraint Networks in Action," W.Horn (ed.) Proceedings of the 14th European Conference on Artificial Intelligence (ECAI'00), IOS Press, Amsterdam, 2000.
A larger preliminary version in Proc. of the Temporal Reasoning Workshop (TARRAT'99), associated to CAEPIA-TTIA'99, Murcia, Spain. 1999.

P. Cabalar, M. Cabarcos, R. P. Otero, "PAL: Pertinence Action Language," Proceedings of the 8th Intl. Workshop on Non-Monotonic Reasoning NMR'2000,  April 9-11, Breckenridge, Colorado, USA, April 2000.  (Collocated with KR'2000, April 12-15) [PAL web page]

1999

P. Cabalar, "Temporal Answer Sets," Proceedings of the Joint Conference on Declarative Programming, (APPIA-GULP-PRODE'99), L'Aquila, Italy, September 6-9, 1999.

R. P. Otero, P. Cabalar, "Pertinence and Causality," Proceedings of the 3rd Workshop on Nonmonotonic Reasoning, Action, and Change (NRAC), IJCAI'99, Stockholm, Sweden. August 1999.



Old research work related to temporal expert systems and DEVS:

P. Cabalar, M. Cabarcos, R. P. Otero, A. Barreiro, "Introducing Planning in Discrete Event Systems," Lecture Notes in Computer Science, (1333):146-159, 1997.

M. Cabarcos, M. Otero, P. Cabalar, R. P. Otero, "Efficient Concurrent Execution of Medtool Expert Systems," Conference on Artificial Intelligence Applications (EXPERSYS'96), Paris, 1996.

R. P. Otero, A. Barreiro, P. Cabalar, D. Lorenzo, "Discrete Event Simulation in an Environment for Temporal Expert Systems," Lecture Notes in Computer Science, (1030):271-282, 1996.

R. P. Otero, D. Lorenzo, P. Cabalar, "Automatic Induction of DEVS Structures," Lecture Notes in Computer Science, (1030):305-313, 1996.

R. P. Otero, D. Lorenzo, P. Cabalar, "Applying Induction in Temporal Expert Systems," Proceedings of the Workshop of Data Engineering for Inductive Learning, IJCAI'95, Montréal, 1995.
last updated: May 27th 2016