TY - JOUR A1 - Besnard, Philippe A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - Paraconsistent reasoning via quantified boolean formulas Y1 - 2002 SN - 3-540-44190-5 ER - TY - JOUR A1 - Brain, Martin A1 - Gebser, Martin A1 - Pührer, Jörg A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - "That is illogical, Captain!" : the debugging support tool spock for answer-set programs ; system description Y1 - 2007 ER - TY - JOUR A1 - Pearce, David A1 - Sarsakov, Vladimir A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - A polynomial translation of logic programs with nested expressions into disjunctive logic programs : preliminary report Y1 - 2002 ER - TY - JOUR A1 - Schaub, Torsten H. A1 - Woltran, Stefan T1 - Answer set programming unleashed! JF - Künstliche Intelligenz N2 - Answer Set Programming faces an increasing popularity for problem solving in various domains. While its modeling language allows us to express many complex problems in an easy way, its solving technology enables their effective resolution. In what follows, we detail some of the key factors of its success. Answer Set Programming [ASP; Brewka et al. Commun ACM 54(12):92–103, (2011)] is seeing a rapid proliferation in academia and industry due to its easy and flexible way to model and solve knowledge-intense combinatorial (optimization) problems. To this end, ASP offers a high-level modeling language paired with high-performance solving technology. As a result, ASP systems provide out-off-the-box, general-purpose search engines that allow for enumerating (optimal) solutions. They are represented as answer sets, each being a set of atoms representing a solution. The declarative approach of ASP allows a user to concentrate on a problem’s specification rather than the computational means to solve it. This makes ASP a prime candidate for rapid prototyping and an attractive tool for teaching key AI techniques since complex problems can be expressed in a succinct and elaboration tolerant way. This is eased by the tuning of ASP’s modeling language to knowledge representation and reasoning (KRR). The resulting impact is nicely reflected by a growing range of successful applications of ASP [Erdem et al. AI Mag 37(3):53–68, 2016; Falkner et al. Industrial applications of answer set programming. K++nstliche Intelligenz (2018)] Y1 - 2018 U6 - https://doi.org/10.1007/s13218-018-0550-z SN - 0933-1875 SN - 1610-1987 VL - 32 IS - 2-3 SP - 105 EP - 108 PB - Springer CY - Heidelberg ER - TY - GEN A1 - Schaub, Torsten H. A1 - Woltran, Stefan T1 - Special issue on answer set programming T2 - Künstliche Intelligenz Y1 - 2018 U6 - https://doi.org/10.1007/s13218-018-0554-8 SN - 0933-1875 SN - 1610-1987 VL - 32 IS - 2-3 SP - 101 EP - 103 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Besnard, Philippe A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - Paraconsistent reasoning via quantified boolean formulas : Part II: Circumscribing inconsistent theories Y1 - 2003 SN - 3-540- 409494-5 ER - TY - JOUR A1 - Delgrande, James A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - A model-theoretic approach to belief change in answer set programming JF - ACM transactions on computational logic N2 - We address the problem of belief change in (nonmonotonic) logic programming under answer set semantics. Our formal techniques are analogous to those of distance-based belief revision in propositional logic. In particular, we build upon the model theory of logic programs furnished by SE interpretations, where an SE interpretation is a model of a logic program in the same way that a classical interpretation is a model of a propositional formula. Hence we extend techniques from the area of belief revision based on distance between models to belief change in logic programs. We first consider belief revision: for logic programs P and Q, the goal is to determine a program R that corresponds to the revision of P by Q, denoted P * Q. We investigate several operators, including (logic program) expansion and two revision operators based on the distance between the SE models of logic programs. It proves to be the case that expansion is an interesting operator in its own right, unlike in classical belief revision where it is relatively uninteresting. Expansion and revision are shown to satisfy a suite of interesting properties; in particular, our revision operators satisfy all or nearly all of the AGM postulates for revision. We next consider approaches for merging a set of logic programs, P-1,...,P-n. Again, our formal techniques are based on notions of relative distance between the SE models of the logic programs. Two approaches are examined. The first informally selects for each program P-i those models of P-i that vary the least from models of the other programs. The second approach informally selects those models of a program P-0 that are closest to the models of programs P-1,...,P-n. In this case, P-0 can be thought of as a set of database integrity constraints. We examine these operators with regards to how they satisfy relevant postulate sets. Last, we present encodings for computing the revision as well as the merging of logic programs within the same logic programming framework. This gives rise to a direct implementation of our approach in terms of off-the-shelf answer set solvers. These encodings also reflect the fact that our change operators do not increase the complexity of the base formalism. KW - Theory KW - Answer set programming KW - belief revision KW - belief merging KW - program encodings KW - strong equivalence Y1 - 2013 U6 - https://doi.org/10.1145/2480759.2480766 SN - 1529-3785 VL - 14 IS - 2 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Brain, Martin A1 - Gebser, Martin A1 - Pührer, Jörg A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - Debugging ASP programs by means of ASP Y1 - 2007 SN - 978-3-540- 72199-4 ER - TY - JOUR A1 - Gebser, Martin A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - Alternative characterizations for program equivalence under aswer-set semantics : a preliminary report Y1 - 2007 ER - TY - JOUR A1 - Bordihn, Henning A1 - Fernau, Henning A1 - Holzer, Markus A1 - Manca, Vincenzo A1 - Martin-Vide, Carlos T1 - Iterated sequential transducers as language generating devices JF - Theoretical computer science N2 - Iterated finite state sequential transducers are considered as language generating devices. The hierarchy induced by the size of the state alphabet is proved to collapse to the fourth level. The corresponding language families are related to the families of languages generated by Lindenmayer systems and Chomsky grammars. Finally, some results on deterministic and extended iterated finite state transducers are established. KW - finite state sequential transducers KW - state complexity KW - Lindenmayer systems Y1 - 2006 U6 - https://doi.org/10.1016/j.tcs.2006.07.059 SN - 0304-3975 VL - 369 IS - 1 SP - 67 EP - 81 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Stoffel, Dominik A1 - Kunz, Wolfgang A1 - Gerber, Stefan T1 - And/Or reasoning graphs for determining prime implicants in multi-level combinational networks Y1 - 1997 ER - TY - THES A1 - Gerber, Stefan T1 - Using software for fault detection in arithmetical circuits Y1 - 1995 ER - TY - JOUR A1 - Baier, Thomas A1 - Di Ciccio, Claudio A1 - Mendling, Jan A1 - Weske, Mathias T1 - Matching events and activities by integrating behavioral aspects and label analysis JF - Software and systems modeling N2 - Nowadays, business processes are increasingly supported by IT services that produce massive amounts of event data during the execution of a process. These event data can be used to analyze the process using process mining techniques to discover the real process, measure conformance to a given process model, or to enhance existing models with performance information. Mapping the produced events to activities of a given process model is essential for conformance checking, annotation and understanding of process mining results. In order to accomplish this mapping with low manual effort, we developed a semi-automatic approach that maps events to activities using insights from behavioral analysis and label analysis. The approach extracts Declare constraints from both the log and the model to build matching constraints to efficiently reduce the number of possible mappings. These mappings are further reduced using techniques from natural language processing, which allow for a matching based on labels and external knowledge sources. The evaluation with synthetic and real-life data demonstrates the effectiveness of the approach and its robustness toward non-conforming execution logs. KW - Process mining KW - Event mapping KW - Business process intelligence KW - Constraint satisfaction KW - Declare KW - Natural language processing Y1 - 2018 U6 - https://doi.org/10.1007/s10270-017-0603-z SN - 1619-1366 SN - 1619-1374 VL - 17 IS - 2 SP - 573 EP - 598 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Przybylla, Mareen A1 - Romeike, Ralf T1 - Empowering learners with tools in CS education BT - physical computing in secondary schools JF - it - Information Technology N2 - In computer science, computer systems are both, objects of investigation and tools that enable creative learning and design. Tools for learning have a long tradition in computer science education. Already in the late 1960s, Papert developed a concept which had an immense impact on the development of informal education in the following years: his theory of constructionism understands learning as a creative process of knowledge construction that is most effective when learners create something purposeful that they can try out, show around, discuss, analyse and receive praise for. By now, there are numerous learning and programming environments that are based on the constructionist ideas. Modern tools offer opportunities for students to learn in motivating ways and gain impressive results in programming games, animations, implementing 3D models or developing interactive objects. This article gives an overview of computer science education research related to tools and media to be used in educational settings. We analyse different types of tools with a special focus on the categorization and development of tools for student adequate physical computing activities in the classroom. Research around the development and evaluation of tools and learning resources in the domain of physical computing is illustrated with the example of "My Interactive Garden", a constructionist learning and programming environment. It is explained how the results from empirical studies are integrated in the continuous development of the learning material. KW - tools KW - media KW - resources KW - computer science education KW - physical computing Y1 - 2018 U6 - https://doi.org/10.1515/itit-2017-0032 SN - 1611-2776 SN - 2196-7032 VL - 60 IS - 2 SP - 91 EP - 101 PB - De Gruyter CY - Berlin ER - TY - GEN A1 - Frank, Mario A1 - Kreitz, Christoph T1 - A theorem prover for scientific and educational purposes T2 - Electronic proceedings in theoretical computer science N2 - We present a prototype of an integrated reasoning environment for educational purposes. The presented tool is a fragment of a proof assistant and automated theorem prover. We describe the existing and planned functionality of the theorem prover and especially the functionality of the educational fragment. This currently supports working with terms of the untyped lambda calculus and addresses both undergraduate students and researchers. We show how the tool can be used to support the students' understanding of functional programming and discuss general problems related to the process of building theorem proving software that aims at supporting both research and education. Y1 - 2018 U6 - https://doi.org/10.4204/EPTCS.267.4 SN - 2075-2180 IS - 267 SP - 59 EP - 69 PB - Open Publishing Association CY - Sydney ER - TY - GEN A1 - Schäpers, Björn A1 - Niemueller, Tim A1 - Lakemeyer, Gerhard A1 - Gebser, Martin A1 - Schaub, Torsten H. T1 - ASP-Based Time-Bounded Planning for Logistics Robots T2 - Twenty-Eighth International Conference on Automated Planning and Scheduling (ICAPS 2018) N2 - Manufacturing industries are undergoing a major paradigm shift towards more autonomy. Automated planning and scheduling then becomes a necessity. The Planning and Execution Competition for Logistics Robots in Simulation held at ICAPS is based on this scenario and provides an interesting testbed. However, the posed problem is challenging as also demonstrated by the somewhat weak results in 2017. The domain requires temporal reasoning and dealing with uncertainty. We propose a novel planning system based on Answer Set Programming and the Clingo solver to tackle these problems and incentivize robot cooperation. Our results show a significant performance improvement, both, in terms of lowering computational requirements and better game metrics. Y1 - 2018 SN - 2334-0835 SN - 2334-0843 SP - 509 EP - 517 PB - ASSOC Association for the Advancement of Artificial Intelligence CY - Palo Alto ER - TY - CHAP A1 - Knoth, Alexander Henning A1 - Kiy, Alexander T1 - (Self-)confident through the introductory study phase with the Reflect App BT - (Self-)confident through the introductory study phase with the Reflect App T2 - CEUR Workshop Proceedings T2 - Selbst-bewusst durch die Studieneingangsphase mit der Reflect-App Y1 - 2014 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84921875162&partnerID=MN8TOARS SN - 1613-0073 IS - 1227 SP - 172 EP - 179 PB - CEUR-WS CY - Freiburg ER - TY - JOUR A1 - Ly, Ibrahim A1 - Tarkhanov, Nikolai Nikolaevich T1 - A variational approach to the Cauchy problem for nonlinear elliptic differential equations N2 - We discuss the relaxation of a class of nonlinear elliptic Cauchy problems with data on a piece S of the boundary surface by means of a variational approach known in the optimal control literature as "equation error method". By the Cauchy problem is meant any boundary value problem for an unknown function y in a domain X with the property that the data on S, if combined with the differential equations in X, allow one to determine all derivatives of y on S by means of functional equations. In the case of real analytic data of the Cauchy problem, the existence of a local solution near S is guaranteed by the Cauchy-Kovalevskaya theorem. We also admit overdetermined elliptic systems, in which case the set of those Cauchy data on S for which the Cauchy problem is solvable is very "thin". For this reason we discuss a variational setting of the Cauchy problem which always possesses a generalised solution. Y1 - 2009 UR - http://dx.doi.org/10.1515/jiip U6 - https://doi.org/10.1515/Jiip.2009.037 SN - 0928-0219 ER - TY - JOUR A1 - Prasse, Paul A1 - Iversen, Pascal A1 - Lienhard, Matthias A1 - Thedinga, Kristina A1 - Herwig, Ralf A1 - Scheffer, Tobias T1 - Pre-Training on In Vitro and Fine-Tuning on Patient-Derived Data Improves Deep Neural Networks for Anti-Cancer Drug-Sensitivity Prediction JF - MDPI N2 - Large-scale databases that report the inhibitory capacities of many combinations of candidate drug compounds and cultivated cancer cell lines have driven the development of preclinical drug-sensitivity models based on machine learning. However, cultivated cell lines have devolved from human cancer cells over years or even decades under selective pressure in culture conditions. Moreover, models that have been trained on in vitro data cannot account for interactions with other types of cells. Drug-response data that are based on patient-derived cell cultures, xenografts, and organoids, on the other hand, are not available in the quantities that are needed to train high-capacity machine-learning models. We found that pre-training deep neural network models of drug sensitivity on in vitro drug-sensitivity databases before fine-tuning the model parameters on patient-derived data improves the models’ accuracy and improves the biological plausibility of the features, compared to training only on patient-derived data. From our experiments, we can conclude that pre-trained models outperform models that have been trained on the target domains in the vast majority of cases. KW - deep neural networks KW - drug-sensitivity prediction KW - anti-cancer drugs Y1 - 2022 U6 - https://doi.org/10.3390/cancers14163950 SN - 2072-6694 VL - 14 SP - 1 EP - 14 PB - MDPI CY - Basel, Schweiz ET - 16 ER - TY - JOUR A1 - Everardo Pérez, Flavio Omar A1 - Osorio, Mauricio T1 - Towards an answer set programming methodology for constructing programs following a semi-automatic approach BT - extended and revised version JF - Electronic notes in theoretical computer science N2 - Answer Set Programming (ASP) is a successful rule-based formalism for modeling and solving knowledge-intense combinatorial (optimization) problems. Despite its success in both academic and industry, open challenges like automatic source code optimization, and software engineering remains. This is because a problem encoded into an ASP might not have the desired solving performance compared to an equivalent representation. Motivated by these two challenges, this paper has three main contributions. First, we propose a developing process towards a methodology to implement ASP programs, being faithful to existing methods. Second, we present ASP encodings that serve as the basis from the developing process. Third, we demonstrate the use of ASP to reverse the standard solving process. That is, knowing answer sets in advance, and desired strong equivalent properties, “we” exhaustively reconstruct ASP programs if they exist. This paper was originally motivated by the search of propositional formulas (if they exist) that represent the semantics of a new aggregate operator. Particularly, a parity aggregate. This aggregate comes as an improvement from the already existing parity (xor) constraints from xorro, where lacks expressiveness, even though these constraints fit perfectly for reasoning modes like sampling or model counting. To this end, this extended version covers the fundaments from parity constraints as well as the xorro system. Hence, we delve a little more in the examples and the proposed methodology over parity constraints. Finally, we discuss our results by showing the only representation available, that satisfies different properties from the classical logic xor operator, which is also consistent with the semantics of parity constraints from xorro. KW - answer set programming KW - combinatorial optimization problems KW - parity aggregate operator Y1 - 2020 U6 - https://doi.org/10.1016/j.entcs.2020.10.004 SN - 1571-0661 VL - 354 SP - 29 EP - 44 PB - Elsevier CY - Amsterdam [u.a.] ER -