@article{DelgrandeLiuSchaubetal.2006,
  author    = {Delgrande, James Patrick and Liu, Daphne H. and Schaub, Torsten and Thiele, Sven},
  title     = {COBA 2.0 : a consistency-based belief change system},
  year      = {2006},
  language  = {en}
}
@article{NicolasSchaub1998,
  author    = {Nicolas, Pascal and Schaub, Torsten},
  title     = {Un cadre g{\´e}n{\´e}ral pour l'interrogation automatique en logiques des d{\´e}fauts},
  year      = {1998},
  language  = {fr}
}
@article{LindauerHoosHutteretal.2015,
  author    = {Lindauer, Marius and Hoos, Holger H. and Hutter, Frank and Schaub, Torsten},
  title     = {An automatically configured algorithm selector},
  series = {The journal of artificial intelligence research},
  volume    = {53},
  journal   = {The journal of artificial intelligence research},
  publisher = {AI Access Foundation},
  address   = {Marina del Rey},
  issn      = {1076-9757},
  pages     = {745 -- 778},
  year      = {2015},
  abstract  = {Algorithm selection (AS) techniques - which involve choosing from a set of algorithms the one expected to solve a given problem instance most efficiently - have substantially improved the state of the art in solving many prominent AI problems, such as SAT, CSP, ASP, MAXSAT and QBF. Although several AS procedures have been introduced, not too surprisingly, none of them dominates all others across all AS scenarios. Furthermore, these procedures have parameters whose optimal values vary across AS scenarios. This holds specifically for the machine learning techniques that form the core of current AS procedures, and for their hyperparameters. Therefore, to successfully apply AS to new problems, algorithms and benchmark sets, two questions need to be answered: (i) how to select an AS approach and (ii) how to set its parameters effectively. We address both of these problems simultaneously by using automated algorithm configuration. Specifically, we demonstrate that we can automatically configure claspfolio 2, which implements a large variety of different AS approaches and their respective parameters in a single, highly-parameterized algorithm framework. Our approach, dubbed AutoFolio, allows researchers and practitioners across a broad range of applications to exploit the combined power of many different AS methods. We demonstrate AutoFolio can significantly improve the performance of claspfolio 2 on 8 out of the 13 scenarios from the Algorithm Selection Library, leads to new state-of-the-art algorithm selectors for 7 of these scenarios, and matches state-of-the-art performance (statistically) on all other scenarios. Compared to the best single algorithm for each AS scenario, AutoFolio achieves average speedup factors between 1.3 and 15.4.},
  language  = {en}
}
@article{HoosLindauerSchaub2014,
  author    = {Hoos, Holger and Lindauer, Marius and Schaub, Torsten},
  title     = {claspfolio 2},
  series = {Theory and practice of logic programming},
  volume    = {14},
  journal   = {Theory and practice of logic programming},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068414000210},
  pages     = {569 -- 585},
  year      = {2014},
  abstract  = {Building on the award-winning, portfolio-based ASP solver claspfolio, we present claspfolio 2, a modular and open solver architecture that integrates several different portfolio-based algorithm selection approaches and techniques. The claspfolio 2 solver framework supports various feature generators, solver selection approaches, solver portfolios, as well as solver-schedule-based pre-solving techniques. The default configuration of claspfolio 2 relies on a light-weight version of the ASP solver clasp to generate static and dynamic instance features. The flexible open design of claspfolio 2 is a distinguishing factor even beyond ASP. As such, it provides a unique framework for comparing and combining existing portfolio-based algorithm selection approaches and techniques in a single, unified framework. Taking advantage of this, we conducted an extensive experimental study to assess the impact of different feature sets, selection approaches and base solver portfolios. In addition to gaining substantial insights into the utility of the various approaches and techniques, we identified a default configuration of claspfolio 2 that achieves substantial performance gains not only over clasp's default configuration and the earlier version of claspfolio, but also over manually tuned configurations of clasp.},
  language  = {en}
}
@article{TranPontelliBalduccinietal.2022,
  author    = {Tran, Son Cao and Pontelli, Enrico and Balduccini, Marcello and Schaub, Torsten},
  title     = {Answer set planning},
  series = {Theory and practice of logic programming},
  journal   = {Theory and practice of logic programming},
  publisher = {Cambridge University Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068422000072},
  pages     = {73},
  year      = {2022},
  abstract  = {Answer Set Planning refers to the use of Answer Set Programming (ASP) to compute plans, that is, solutions to planning problems, that transform a given state of the world to another state. The development of efficient and scalable answer set solvers has provided a significant boost to the development of ASP-based planning systems. This paper surveys the progress made during the last two and a half decades in the area of answer set planning, from its foundations to its use in challenging planning domains. The survey explores the advantages and disadvantages of answer set planning. It also discusses typical applications of answer set planning and presents a set of challenges for future research.},
  language  = {en}
}
@article{BrainGebserPuehreretal.2007,
  author    = {Brain, Martin and Gebser, Martin and P{\"u}hrer, J{\"o}rg and Schaub, Torsten and Tompits, Hans and Woltran, Stefan},
  title     = {Debugging ASP programs by means of ASP},
  isbn      = {978-3-540- 72199-4},
  year      = {2007},
  language  = {en}
}
@article{MileoSchaubMericoetal.2011,
  author    = {Mileo, Alessandra and Schaub, Torsten and Merico, Davide and Bisiani, Roberto},
  title     = {Knowledge-based multi-criteria optimization to support indoor positioning},
  series = {Annals of mathematics and artificial intelligence},
  volume    = {62},
  journal   = {Annals of mathematics and artificial intelligence},
  number    = {3-4},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {1012-2443},
  doi       = {10.1007/s10472-011-9241-2},
  pages     = {345 -- 370},
  year      = {2011},
  abstract  = {Indoor position estimation constitutes a central task in home-based assisted living environments. Such environments often rely on a heterogeneous collection of low-cost sensors whose diversity and lack of precision has to be compensated by advanced techniques for localization and tracking. Although there are well established quantitative methods in robotics and neighboring fields for addressing these problems, they lack advanced knowledge representation and reasoning capacities. Such capabilities are not only useful in dealing with heterogeneous and incomplete information but moreover they allow for a better inclusion of semantic information and more general homecare and patient-related knowledge. We address this problem and investigate how state-of-the-art localization and tracking methods can be combined with Answer Set Programming, as a popular knowledge representation and reasoning formalism. We report upon a case-study and provide a first experimental evaluation of knowledge-based position estimation both in a simulated as well as in a real setting.},
  language  = {en}
}
@article{FandinoLifschitzLuehneetal.2020,
  author    = {Fandi{\~n}o, Jorge and Lifschitz, Vladimir and L{\"u}hne, Patrick and Schaub, Torsten},
  title     = {Verifying tight logic programs with Anthem and Vampire},
  series = {Theory and practice of logic programming},
  volume    = {20},
  journal   = {Theory and practice of logic programming},
  number    = {5},
  publisher = {Cambridge Univ. Press},
  address   = {Cambridge [u.a.]},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068420000344},
  pages     = {735 -- 750},
  year      = {2020},
  abstract  = {This paper continues the line of research aimed at investigating the relationship between logic programs and first-order theories. We extend the definition of program completion to programs with input and output in a subset of the input language of the ASP grounder gringo, study the relationship between stable models and completion in this context, and describe preliminary experiments with the use of two software tools, anthem and vampire, for verifying the correctness of programs with input and output. Proofs of theorems are based on a lemma that relates the semantics of programs studied in this paper to stable models of first-order formulas.},
  language  = {en}
}
@article{DelgrandeSchaub2000,
  author    = {Delgrande, James Patrick and Schaub, Torsten},
  title     = {A consistency-based model for belief change: preliminary report},
  year      = {2000},
  language  = {en}
}
@article{DelgrandeSchaub2000,
  author    = {Delgrande, James Patrick and Schaub, Torsten},
  title     = {The role of default logic in knowledge representation},
  isbn      = {0-7923-7224-7},
  year      = {2000},
  language  = {en}
}
@article{DelgrandeSchaub2001,
  author    = {Delgrande, James Patrick and Schaub, Torsten},
  title     = {How to reason credulously and skeptically within a single extension},
  year      = {2001},
  language  = {en}
}
@article{SchaubWang2001,
  author    = {Schaub, Torsten and Wang, Kewen},
  title     = {A comparative study of logic programs with preference},
  year      = {2001},
  language  = {en}
}
@article{DelgrandeLangSchaub2007,
  author    = {Delgrande, James Patrick and Lang, J{\´e}r{\^o}me and Schaub, Torsten},
  title     = {Belief change based on global minimisation},
  year      = {2007},
  language  = {en}
}
@article{DurzinskyMarwanOstrowskietal.2011,
  author    = {Durzinsky, Markus and Marwan, Wolfgang and Ostrowski, Max and Schaub, Torsten and Wagler, Annegret},
  title     = {Automatic network reconstruction using ASP},
  series = {Theory and practice of logic programming},
  volume    = {11},
  journal   = {Theory and practice of logic programming},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068411000287},
  pages     = {749 -- 766},
  year      = {2011},
  abstract  = {Building biological models by inferring functional dependencies from experimental data is an important issue in Molecular Biology. To relieve the biologist from this traditionally manual process, various approaches have been proposed to increase the degree of automation. However, available approaches often yield a single model only, rely on specific assumptions, and/or use dedicated, heuristic algorithms that are intolerant to changing circumstances or requirements in the view of the rapid progress made in Biotechnology. Our aim is to provide a declarative solution to the problem by appeal to Answer Set Programming (ASP) overcoming these difficulties. We build upon an existing approach to Automatic Network Reconstruction proposed by part of the authors. This approach has firm mathematical foundations and is well suited for ASP due to its combinatorial flavor providing a characterization of all models explaining a set of experiments. The usage of ASP has several benefits over the existing heuristic algorithms. First, it is declarative and thus transparent for biological experts. Second, it is elaboration tolerant and thus allows for an easy exploration and incorporation of biological constraints. Third, it allows for exploring the entire space of possible models. Finally, our approach offers an excellent performance, matching existing, special-purpose systems.},
  language  = {en}
}
@article{GebserSchaub2013,
  author    = {Gebser, Martin and Schaub, Torsten},
  title     = {Tableau calculi for logic programs under answer set semantics},
  series = {ACM transactions on computational logic},
  volume    = {14},
  journal   = {ACM transactions on computational logic},
  number    = {2},
  publisher = {Association for Computing Machinery},
  address   = {New York},
  issn      = {1529-3785},
  doi       = {10.1145/2480759.2480767},
  pages     = {40},
  year      = {2013},
  abstract  = {We introduce formal proof systems based on tableau methods for analyzing computations in Answer Set Programming (ASP). Our approach furnishes fine-grained instruments for characterizing operations as well as strategies of ASP solvers. The granularity is detailed enough to capture a variety of propagation and choice methods of algorithms used for ASP solving, also incorporating SAT-based and conflict-driven learning approaches to some extent. This provides us with a uniform setting for identifying and comparing fundamental properties of ASP solving approaches. In particular, we investigate their proof complexities and show that the run-times of best-case computations can vary exponentially between different existing ASP solvers. Apart from providing a framework for comparing ASP solving approaches, our characterizations also contribute to their understanding by pinning down the constitutive atomic operations. Furthermore, our framework is flexible enough to integrate new inference patterns, and so to study their relation to existing ones. To this end, we generalize our approach and provide an extensible basis aiming at a modular incorporation of additional language constructs. This is exemplified by augmenting our basic tableau methods with cardinality constraints and disjunctions.},
  language  = {en}
}
@article{OstrowskiSchaub2012,
  author    = {Ostrowski, Max and Schaub, Torsten},
  title     = {ASP modulo CSP The clingcon system},
  series = {Theory and practice of logic programming},
  volume    = {12},
  journal   = {Theory and practice of logic programming},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068412000142},
  pages     = {485 -- 503},
  year      = {2012},
  abstract  = {We present the hybrid ASP solver clingcon, combining the simple modeling language and the high performance Boolean solving capacities of Answer Set Programming (ASP) with techniques for using non-Boolean constraints from the area of Constraint Programming (CP). The new clingcon system features an extended syntax supporting global constraints and optimize statements for constraint variables. The major technical innovation improves the interaction between ASP and CP solver through elaborated learning techniques based on irreducible inconsistent sets. A broad empirical evaluation shows that these techniques yield a performance improvement of an order of magnitude.},
  language  = {en}
}
@article{BrewkaEllmauthalerKernIsberneretal.2018,
  author    = {Brewka, Gerhard and Ellmauthaler, Stefan and Kern-Isberner, Gabriele and Obermeier, Philipp and Ostrowski, Max and Romero, Javier and Schaub, Torsten and Schieweck, Steffen},
  title     = {Advanced solving technology for dynamic and reactive applications},
  series = {K{\"u}nstliche Intelligenz},
  volume    = {32},
  journal   = {K{\"u}nstliche Intelligenz},
  number    = {2-3},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {0933-1875},
  doi       = {10.1007/s13218-018-0538-8},
  pages     = {199 -- 200},
  year      = {2018},
  language  = {en}
}
@article{GebserSchaubThiele2007,
  author    = {Gebser, Martin and Schaub, Torsten and Thiele, Sven},
  title     = {GrinGo : a new grounder for answer set programming},
  isbn      = {978-3-540- 72199-4},
  year      = {2007},
  language  = {en}
}
@article{BesnardSchaub1995,
  author    = {Besnard, Philippe and Schaub, Torsten},
  title     = {An approach to context-based default reasoning},
  issn      = {0169-2968},
  year      = {1995},
  language  = {en}
}
@article{DimopoulosGebserLuehneetal.2019,
  author    = {Dimopoulos, Yannis and Gebser, Martin and L{\"u}hne, Patrick and Romero Davila, Javier and Schaub, Torsten},
  title     = {plasp 3},
  series = {Theory and practice of logic programming},
  volume    = {19},
  journal   = {Theory and practice of logic programming},
  number    = {3},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068418000583},
  pages     = {477 -- 504},
  year      = {2019},
  abstract  = {We describe the new version of the Planning Domain Definition Language (PDDL)-to-Answer Set Programming (ASP) translator plasp. First, it widens the range of accepted PDDL features. Second, it contains novel planning encodings, some inspired by Satisfiability Testing (SAT) planning and others exploiting ASP features such as well-foundedness. All of them are designed for handling multivalued fluents in order to capture both PDDL as well as SAS planning formats. Third, enabled by multishot ASP solving, it offers advanced planning algorithms also borrowed from SAT planning. As a result, plasp provides us with an ASP-based framework for studying a variety of planning techniques in a uniform setting. Finally, we demonstrate in an empirical analysis that these techniques have a significant impact on the performance of ASP planning.},
  language  = {en}
}
@article{KaminskiSchaubSiegeletal.2013,
  author    = {Kaminski, Roland and Schaub, Torsten and Siegel, Anne and Videla, Santiago},
  title     = {Minimal intervention strategies in logical signaling networks with ASP},
  series = {Theory and practice of logic programming},
  volume    = {13},
  journal   = {Theory and practice of logic programming},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068413000422},
  pages     = {675 -- 690},
  year      = {2013},
  abstract  = {Proposing relevant perturbations to biological signaling networks is central to many problems in biology and medicine because it allows for enabling or disabling certain biological outcomes. In contrast to quantitative methods that permit fine-grained (kinetic) analysis, qualitative approaches allow for addressing large-scale networks. This is accomplished by more abstract representations such as logical networks. We elaborate upon such a qualitative approach aiming at the computation of minimal interventions in logical signaling networks relying on Kleene's three-valued logic and fixpoint semantics. We address this problem within answer set programming and show that it greatly outperforms previous work using dedicated algorithms.},
  language  = {en}
}
@article{SchaubBrueningNicolas1996,
  author    = {Schaub, Torsten and Br{\"u}ning, Stefan and Nicolas, Pascal},
  title     = {XRay : a prolog technology theorem prover for default reasoning: a system description},
  isbn      = {3-540-61511-3},
  year      = {1996},
  language  = {en}
}
@article{BesnardSchaub1996,
  author    = {Besnard, Philippe and Schaub, Torsten},
  title     = {A simple signed system for paraconsistent reasoning},
  isbn      = {3-540-61630-6},
  year      = {1996},
  language  = {en}
}
@article{GebserSchaubTompitsetal.2007,
  author    = {Gebser, Martin and Schaub, Torsten and Tompits, Hans and Woltran, Stefan},
  title     = {Alternative characterizations for program equivalence under aswer-set semantics : a preliminary report},
  year      = {2007},
  language  = {en}
}
@article{GebserObermeierSchaubetal.2018,
  author    = {Gebser, Martin and Obermeier, Philipp and Schaub, Torsten and Ratsch-Heitmann, Michel and Runge, Mario},
  title     = {Routing driverless transport vehicles in car assembly with answer set programming},
  series = {Theory and practice of logic programming},
  volume    = {18},
  journal   = {Theory and practice of logic programming},
  number    = {3-4},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068418000182},
  pages     = {520 -- 534},
  year      = {2018},
  abstract  = {Automated storage and retrieval systems are principal components of modern production and warehouse facilities. In particular, automated guided vehicles nowadays substitute human-operated pallet trucks in transporting production materials between storage locations and assembly stations. While low-level control systems take care of navigating such driverless vehicles along programmed routes and avoid collisions even under unforeseen circumstances, in the common case of multiple vehicles sharing the same operation area, the problem remains how to set up routes such that a collection of transport tasks is accomplished most effectively. We address this prevalent problem in the context of car assembly at Mercedes-Benz Ludwigsfelde GmbH, a large-scale producer of commercial vehicles, where routes for automated guided vehicles used in the production process have traditionally been hand-coded by human engineers. Such adhoc methods may suffice as long as a running production process remains in place, while any change in the factory layout or production targets necessitates tedious manual reconfiguration, not to mention the missing portability between different production plants. Unlike this, we propose a declarative approach based on Answer Set Programming to optimize the routes taken by automated guided vehicles for accomplishing transport tasks. The advantages include a transparent and executable problem formalization, provable optimality of routes relative to objective criteria, as well as elaboration tolerance towards particular factory layouts and production targets. Moreover, we demonstrate that our approach is efficient enough to deal with the transport tasks evolving in realistic production processes at the car factory of Mercedes-Benz Ludwigsfelde GmbH.},
  language  = {en}
}
@article{LindauerHoosLeytonBrownetal.2017,
  author    = {Lindauer, Marius and Hoos, Holger and Leyton-Brown, Kevin and Schaub, Torsten},
  title     = {Automatic construction of parallel portfolios via algorithm configuration},
  series = {Artificial intelligence},
  volume    = {244},
  journal   = {Artificial intelligence},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0004-3702},
  doi       = {10.1016/j.artint.2016.05.004},
  pages     = {272 -- 290},
  year      = {2017},
  abstract  = {Since 2004, increases in computational power described by Moore's law have substantially been realized in the form of additional cores rather than through faster clock speeds. To make effective use of modern hardware when solving hard computational problems, it is therefore necessary to employ parallel solution strategies. In this work, we demonstrate how effective parallel solvers for propositional satisfiability (SAT), one of the most widely studied NP-complete problems, can be produced automatically from any existing sequential, highly parametric SAT solver. Our Automatic Construction of Parallel Portfolios (ACPP) approach uses an automatic algorithm configuration procedure to identify a set of configurations that perform well when executed in parallel. Applied to two prominent SAT solvers, Lingeling and clasp, our ACPP procedure identified 8-core solvers that significantly outperformed their sequential counterparts on a diverse set of instances from the application and hard combinatorial category of the 2012 SAT Challenge. We further extended our ACPP approach to produce parallel portfolio solvers consisting of several different solvers by combining their configuration spaces. Applied to the component solvers of the 2012 SAT Challenge gold medal winning SAT Solver pfolioUZK, our ACPP procedures produced a significantly better-performing parallel SAT solver.},
  language  = {en}
}
@article{GebserKaminskiKaufmannetal.2018,
  author    = {Gebser, Martin and Kaminski, Roland and Kaufmann, Benjamin and L{\"u}hne, Patrick and Obermeier, Philipp and Ostrowski, Max and Romero Davila, Javier and Schaub, Torsten and Schellhorn, Sebastian and Wanko, Philipp},
  title     = {The Potsdam Answer Set Solving Collection 5.0},
  series = {K{\"u}nstliche Intelligenz},
  volume    = {32},
  journal   = {K{\"u}nstliche Intelligenz},
  number    = {2-3},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {0933-1875},
  doi       = {10.1007/s13218-018-0528-x},
  pages     = {181 -- 182},
  year      = {2018},
  abstract  = {The Potsdam answer set solving collection, or Potassco for short, bundles various tools implementing and/or applying answer set programming. The article at hand succeeds an earlier description of the Potassco project published in Gebser et al. (AI Commun 24(2):107-124, 2011). Hence, we concentrate in what follows on the major features of the most recent, fifth generation of the ASP system clingo and highlight some recent resulting application systems.},
  language  = {en}
}
@article{GebserKaufmannSchaub2012,
  author    = {Gebser, Martin and Kaufmann, Benjamin and Schaub, Torsten},
  title     = {Conflict-driven answer set solving: From theory to practice},
  series = {Artificial intelligence},
  volume    = {187},
  journal   = {Artificial intelligence},
  number    = {8},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0004-3702},
  doi       = {10.1016/j.artint.2012.04.001},
  pages     = {52 -- 89},
  year      = {2012},
  abstract  = {We introduce an approach to computing answer sets of logic programs, based on concepts successfully applied in Satisfiability (SAT) checking. The idea is to view inferences in Answer Set Programming (ASP) as unit propagation on nogoods. This provides us with a uniform constraint-based framework capturing diverse inferences encountered in ASP solving. Moreover, our approach allows us to apply advanced solving techniques from the area of SAT. As a result, we present the first full-fledged algorithmic framework for native conflict-driven ASP solving. Our approach is implemented in the ASP solver clasp that has demonstrated its competitiveness and versatility by winning first places at various solver contests.},
  language  = {en}
}
@article{BesnardSchaubTompitsetal.2002,
  author    = {Besnard, Philippe and Schaub, Torsten and Tompits, Hans and Woltran, Stefan},
  title     = {Paraconsistent reasoning via quantified boolean formulas},
  isbn      = {3-540-44190-5},
  year      = {2002},
  language  = {en}
}
@article{GebserKaufmannNeumannetal.2007,
  author    = {Gebser, Martin and Kaufmann, Benjamin and Neumann, Andr{\´e} and Schaub, Torsten},
  title     = {Clasp : a conflict-driven answer set solver},
  isbn      = {978-3-540- 72199-4},
  year      = {2007},
  language  = {en}
}
@article{BrainFaberMarateaetal.2007,
  author    = {Brain, Martin and Faber, Wolfgang and Maratea, Marco and Polleres, Axel and Schaub, Torsten and Schindlauer, Roman},
  title     = {What should an ASP solver output? : a multiple position paper},
  year      = {2007},
  language  = {en}
}
@article{ThielscherSchaub1995,
  author    = {Thielscher, Michael and Schaub, Torsten},
  title     = {Default reasoning by deductive planning},
  year      = {1995},
  language  = {en}
}
@article{BanbaraSohTamuraetal.2013,
  author    = {Banbara, Mutsunori and Soh, Takehide and Tamura, Naoyuki and Inoue, Katsumi and Schaub, Torsten},
  title     = {Answer set programming as a modeling language for course timetabling},
  series = {Theory and practice of logic programming},
  volume    = {13},
  journal   = {Theory and practice of logic programming},
  number    = {2},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068413000495},
  pages     = {783 -- 798},
  year      = {2013},
  abstract  = {The course timetabling problem can be generally defined as the task of assigning a number of lectures to a limited set of timeslots and rooms, subject to a given set of hard and soft constraints. The modeling language for course timetabling is required to be expressive enough to specify a wide variety of soft constraints and objective functions. Furthermore, the resulting encoding is required to be extensible for capturing new constraints and for switching them between hard and soft, and to be flexible enough to deal with different formulations. In this paper, we propose to make effective use of ASP as a modeling language for course timetabling. We show that our ASP-based approach can naturally satisfy the above requirements, through an ASP encoding of the curriculum-based course timetabling problem proposed in the third track of the second international timetabling competition (ITC-2007). Our encoding is compact and human-readable, since each constraint is individually expressed by either one or two rules. Each hard constraint is expressed by using integrity constraints and aggregates of ASP. Each soft constraint S is expressed by rules in which the head is the form of penalty (S, V, C), and a violation V and its penalty cost C are detected and calculated respectively in the body. We carried out experiments on four different benchmark sets with five different formulations. We succeeded either in improving the bounds or producing the same bounds for many combinations of problem instances and formulations, compared with the previous best known bounds.},
  language  = {en}
}
@article{GebserSabuncuSchaub2011,
  author    = {Gebser, Martin and Sabuncu, Orkunt and Schaub, Torsten},
  title     = {An incremental answer set programming based system for finite model computation},
  series = {AI communications : AICOM ; the European journal on artificial intelligence},
  volume    = {24},
  journal   = {AI communications : AICOM ; the European journal on artificial intelligence},
  number    = {2},
  publisher = {IOS Press},
  address   = {Amsterdam},
  issn      = {0921-7126},
  doi       = {10.3233/AIC-2011-0496},
  pages     = {195 -- 212},
  year      = {2011},
  abstract  = {We address the problem of Finite Model Computation (FMC) of first-order theories and show that FMC can efficiently and transparently be solved by taking advantage of a recent extension of Answer Set Programming (ASP), called incremental Answer Set Programming (iASP). The idea is to use the incremental parameter in iASP programs to account for the domain size of a model. The FMC problem is then successively addressed for increasing domain sizes until an answer set, representing a finite model of the original first-order theory, is found. We implemented a system based on the iASP solver iClingo and demonstrate its competitiveness by showing that it slightly outperforms the winner of the FNT division of CADE's 2009 Automated Theorem Proving (ATP) competition on the respective benchmark collection.},
  language  = {en}
}
@misc{LifschitzSchaubWoltran2018,
  author    = {Lifschitz, Vladimir and Schaub, Torsten and Woltran, Stefan},
  title     = {Interview with Vladimir Lifschitz},
  series = {K{\"u}nstliche Intelligenz},
  volume    = {32},
  journal   = {K{\"u}nstliche Intelligenz},
  number    = {2-3},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {0933-1875},
  doi       = {10.1007/s13218-018-0552-x},
  pages     = {213 -- 218},
  year      = {2018},
  abstract  = {This interview with Vladimir Lifschitz was conducted by Torsten Schaub at the University of Texas at Austin in August 2017. The question set was compiled by Torsten Schaub and Stefan Woltran.},
  language  = {en}
}
@article{DelgrandeSchaubTompits2006,
  author    = {Delgrande, James Patrick and Schaub, Torsten and Tompits, Hans},
  title     = {A Preference-Based Framework for Updating logic Programs : preliminary reports},
  year      = {2006},
  language  = {en}
}
@article{LinkeSchaub1998,
  author    = {Linke, Thomas and Schaub, Torsten},
  title     = {An approach to query-answering in Reiter's default logic and the underlying existence of extensions problem.},
  isbn      = {3-540-65141-1},
  year      = {1998},
  language  = {en}
}
@inproceedings{GebserHinrichsSchaubetal.2010,
  author    = {Gebser, Martin and Hinrichs, Henrik and Schaub, Torsten and Thiele, Sven},
  title     = {xpanda: a (simple) preprocessor for adding multi-valued propositions to ASP},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41466},
  year      = {2010},
  abstract  = {We introduce a simple approach extending the input language of Answer Set Programming (ASP) systems by multi-valued propositions. Our approach is implemented as a (prototypical) preprocessor translating logic programs with multi-valued propositions into logic programs with Boolean propositions only. Our translation is modular and heavily benefits from the expressive input language of ASP. The resulting approach, along with its implementation, allows for solving interesting constraint satisfaction problems in ASP, showing a good performance.},
  language  = {en}
}
@article{CabalarDieguezSchaubetal.2020,
  author    = {Cabalar, Pedro and Dieguez, Martin and Schaub, Torsten and Schuhmann, Anna},
  title     = {Towards metric temporal answer set programming},
  series = {Theory and practice of logic programming},
  volume    = {20},
  journal   = {Theory and practice of logic programming},
  number    = {5},
  publisher = {Cambridge Univ. Press},
  address   = {Cambridge [u.a.]},
  issn      = {1471-0684},
  doi       = {10.1017/S1471068420000307},
  pages     = {783 -- 798},
  year      = {2020},
  abstract  = {We elaborate upon the theoretical foundations of a metric temporal extension of Answer Set Programming. In analogy to previous extensions of ASP with constructs from Linear Temporal and Dynamic Logic, we accomplish this in the setting of the logic of Here-and-There and its non-monotonic extension, called Equilibrium Logic. More precisely, we develop our logic on the same semantic underpinnings as its predecessors and thus use a simple time domain of bounded time steps. This allows us to compare all variants in a uniform framework and ultimately combine them in a common implementation.},
  language  = {en}
}
@article{PearceSarsakovSchaubetal.2002,
  author    = {Pearce, David and Sarsakov, Vladimir and Schaub, Torsten and Tompits, Hans and Woltran, Stefan},
  title     = {A polynomial translation of logic programs with nested expressions into disjunctive logic programs},
  isbn      = {3-540-43930-7},
  year      = {2002},
  language  = {en}
}
@article{AngerGebserJanhunenetal.2006,
  author    = {Anger, Christian and Gebser, Martin and Janhunen, Tomi and Schaub, Torsten},
  title     = {What's a head without a body?},
  year      = {2006},
  language  = {en}
}
@article{MileoSchaub2007,
  author    = {Mileo, Alessandra and Schaub, Torsten},
  title     = {Qualitative constraint enforcement in advanced policy specification},
  year      = {2007},
  language  = {en}
}
@article{DelgrandeSchaub2005,
  author    = {Delgrande, James Patrick and Schaub, Torsten},
  title     = {Expressing default logic variants in default logic},
  issn      = {0955-792X},
  year      = {2005},
  abstract  = {Reiter's default logic is one of the best known and most studied of the approaches to nonmonotonic reasoning. Several variants of default logic have subsequently been proposed to give systems with properties differing from the original. In this paper, we examine the relationship between default logic and its major variants. We accomplish this by translating a default theory under a variant interpretation into a second default theory, under the original Reiter semantics, wherein the variant interpretation is respected. That is, in each case we show that, given an extension of a translated theory, one may extract an extension of the original variant default logic theory. We show how constrained, rational, justified, and cumulative default logic can be expressed in Reiter's default logic. As well, we show how Reiter's default logic can be expressed in rational default logic. From this, we suggest that any such variant can be similarly treated. Consequently, we provide a unification of default logics, showing how the original formulation of default logic may express its variants. Moreover, the translations clearly express the relationships between alternative approaches to default logic. The translations themselves are shown to generally have good properties. Thus, in at least a theoretical sense, we show that these variants are in a sense superfluous, in that for any of these variants of default logic, we can exactly mimic the behaviour of a variant in standard default logic. As well, the translations lend insight into means of classifying the expressive power of default logic variants; specifically we suggest that the property of semi-monotonicity represents a division with respect to expressibility, whereas regularity and cumulativity do not},
  language  = {en}
}
@article{DelgrandeSchaub2004,
  author    = {Delgrande, James Patrick and Schaub, Torsten},
  title     = {Reasoning with sets of preferences in default logic},
  issn      = {0824-7935},
  year      = {2004},
  abstract  = {We present a general approach for representing and reasoning with sets of defaults in default logic, focusing on reasoning about preferences among sets of defaults. First, we consider how to control the application of a set of defaults so that either all apply (if possible) or none do (if not). From this, an approach to dealing with preferences among sets of default rules is developed. We begin with an ordered default theory, consisting of a standard default theory, but with possible preferences on sets of rules. This theory is transformed into a second, standard default theory wherein the preferences are respected. The approach differs from other work, in that we obtain standard default theories and do not rely on prioritized versions of default logic. In practical terms this means we can immediately use existing default logic theorem provers for an implementation. Also, we directly generate just those extensions containing the most preferred applied rules; in contrast, most previous approaches generate all extensions, then select the most preferred. In a major application of the approach, we show how semimonotonic default theories can be encoded so that reasoning can be carried out at the object level. With this, we can reason about default extensions from within the framework of a standard default logic. Hence one can encode notions such as skeptical and credulous conclusions, and can reason about such conclusions within a single extension},
  language  = {en}
}
@article{DelgrandeSchaubTompitsetal.2004,
  author    = {Delgrande, James Patrick and Schaub, Torsten and Tompits, Hans and Wang, Kewen},
  title     = {A classification and survey of preference handling approchaches in nonmonotonic reasoning},
  issn      = {0824-7935},
  year      = {2004},
  abstract  = {In recent years, there has been a large amount of disparate work concerning the representation and reasoning with qualitative preferential information by means of approaches to nonmonotonic reasoning. Given the variety of underlying systems, assumptions, motivations, and intuitions, it is difficult to compare or relate one approach with another. Here, we present an overview and classification for approaches to dealing with preference. A set of criteria for classifying approaches is given, followed by a set of desiderata that an approach might be expected to satisfy. A comprehensive set of approaches is subsequently given and classified with respect to these sets of underlying principles},
  language  = {en}
}
@article{BorchertAngerSchaubetal.2004,
  author    = {Borchert, P. and Anger, Christian and Schaub, Torsten and Truszczynski, M.},
  title     = {Towards systematic benchmarking in answer set programming : the dagstuhl initiative},
  isbn      = {3-540- 20721-x},
  year      = {2004},
  language  = {en}
}
@article{DelgrandeSchaub2004,
  author    = {Delgrande, James Patrick and Schaub, Torsten},
  title     = {Consistency-based approaches to merging knowledge based : preliminary report},
  isbn      = {92-990021-0-X},
  year      = {2004},
  language  = {en}
}
@article{KonczakLinkeSchaub2004,
  author    = {Konczak, Kathrin and Linke, Thomas and Schaub, Torsten},
  title     = {Graphs and cologings for answer set programming : adridged report},
  isbn      = {3-540- 20721-x},
  year      = {2004},
  language  = {en}
}
@article{FloeterSelbigSchaub2004,
  author    = {Fl{\"o}ter, Andr{\´e} and Selbig, Joachim and Schaub, Torsten},
  title     = {Finding metabolic pathways in decision forests},
  isbn      = {3-540-23221-4},
  year      = {2004},
  language  = {en}
}
@article{BoeselLinkeSchaub2004,
  author    = {Boesel, Andreas and Linke, Thomas and Schaub, Torsten},
  title     = {Profiling answer set programming : the visualization component of the noMoRe System},
  isbn      = {3-540-23242-7},
  year      = {2004},
  language  = {en}
}