Conjunctive Query Answering in SH using Knots ⋆ (2009)
Abstract. Answering conjunctive queries (CQs) has been recognized as a key task for the usage of Description Logics (DLs) in a number of applications. The problem has been studied by many authors,...
H.: A RuleML Syntax for Answer-Set Programming (2009)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
The need for sharing knowledge on the Web—and in particular rules in a standardized format—is an important issue. RuleML [1] has been the most prominent effort in this direction so far....
DLV: An Advanced System for Knowledge Representation and Reasoning (2009)
Nicola Leone, Wolfgang Faber, Gerald Pfeifer, Annamaria Bria, Francesco Calimeri, Gelsomina Catalano, ...
DLV [5] is a KRR system which is based on Disjunctive Logic Programming (DLP) [6] under the stable model semantics (also called Answer Set Programming) [4]. Roughly, a DLP program is a set of...
We consider the computation of eigenvectors x = (x1,..., xn) over the integers, where each component xi satisfies |xi | ≤ b for an integer b. We address various problems in this context, and...
Conditional Planning with External Functions (2009)
Davy Van Nieuwenborgh, Thomas Eiter, Dirk Vermeir
Abstract. We introduce the logic-based planning language K c as an extension of K [5]. K c has two advantages upon K. First, the introduction of external function calls in the rules of a planning...
LPForget: A System of Forgetting in Answer Set Programming (2008)
Fu-leung Cheng, Thomas Eiter, Nathan Robinson, Abdul Sattar, Kewen Wang
Abstract. A novel declarative approach of forgetting in answer set programming (ASP) has been proposed recently. In this paper we report a system prototype of forgetting in ASP, called LPForget. It...
Maintenance Goals of Agents in a Dynamic Environment: Formulation and Policy Construction ∗ (2008)
Chitta Baral, Thomas Eiter, Marcus Bjärel, Mutsumi Nakamura
The notion of maintenance often appears in the AI literature in the context of agent behavior and planning. In this paper, we argue that earlier characterizations of the notion of maintenance are not...
Embedding Non-Ground Logic Programs into Autoepistemic Logic for Knowledge Base Combination (2008)
De Bruijn, Jos, Eiter, Thomas, Polleres, Axel, Tompits, Hans
In the context of the Semantic Web, several approaches to the combination of ontologies, given in terms of theories of classical first-order logic, and rule bases have been proposed. They either cast...
On Reversing Actions: Algorithms and Complexity ∗ (2008)
Reversing actions is the following problem: After executing a sequence of actions, which sequence of actions brings the agent back to the state just before this execution (an action reversal)....
dlvhex: A Tool for Semantic-Web Reasoning under the Answer-Set Semantics ⋆ (2008)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
Abstract. We briefly report about the development status of dlvhex, a reasoning engine for HEX-programs, which are nonmonotonic logic programs featuring both higher-order atoms as well as external...
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
Combining description logic systems with other reasoning systems, possibly over the Web, has become an important research issue and calls for advanced methods and algorithms. Among several approaches...
Integration of Multiple Semantics in an Answer Set Framework 1 (2008)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
di semantiche multiple in un framework con
dlvhex: Current Status and Future Issues (2008)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
Abstract — The Semantic Web vision needs formalisms for the Rule Layer that guarantee transparent interoperability with the Ontology Layer, clear semantics and full declarativity. hex-programs are...
Springer. Abduction and the Dualization Problem ⋆ (2008)
Abstract. Computing abductive explanations is an important problem, which has been studied extensively in Artificial Intelligence (AI) and related disciplines. While computing some abductive...
Abstract Complexity Results for Explanations in the Structural-Model Approach (2008)
Thomas Eiter, Thomas Lukasiewicz
We analyze the computational complexity of Halpern and Pearl’s (causal) explanations in the structural-model approach, which are based on their notions of weak and actual cause. In particular, we...
Categories and Subject Descriptors (2008)
This paper considers the problem of dualizing a monotone CNF (equivalently, computing all minimal transversals of a hypergraph), whose associated decision problem is a prominent open problem in...
Assumption Sets for Extended Logic Programs (2008)
Thomas Eiter, Nicola Leone, David Pearce
Generalising the ideas of [10] we define a simple extension of the notion of unfounded set, called assumption set, that applies to disjunctive logic programs with strong negation. We show that...
Management]: Languages—query languages (2008)
Evgeny Dantsin, Thomas Eiter, Georg Gottlob, Andrei Voronkov
This article surveys various complexity and expressiveness results on different forms of logic programming. The main focus is on decidable forms of logic programming, in particular, propositional...
Theoretical Computer Science, to appear. Decision Lists and Related Boolean Functions ¢¡¤£ (2008)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
We consider Boolean functions represented by decision lists, and study their relationships to other classes of Boolean functions. It turns out that the elementary class of 1-decision lists has...
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
Abstract. Recently, several approaches for updating knowledge bases represented as logic programs have been proposed. We present a generic framework for declarative specifications of update policies,...
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer
Most recently, Answer Set Programming (ASP) has been attracting interest as a new paradigm for problem solving. An important aspect, for which several approaches have been presented, is the handling...
On Reversing Actions: Algorithms and Complexity ∗ (2008)
Reversing actions is the following problem: After executing a sequence of actions, which sequence of actions brings the agent back to the state just before this execution (an action reversal)....
Complexity Results for Checking Equivalence of Stratified Logic Programs ∗ (2008)
Thomas Eiter, Michael Fink, Hans Tompits, Stefan Woltran
Recent research in nonmonotonic logic programming under the answer-set semantics focuses on different notions of program equivalence. However, previous results do not address the important classes of...
Reasoning methods for personalization on the semantic web (2008)
Grigoris Antoniou, Matteo Baldoni, Cristina Baroglio, Viviana Patti, Robert Baumgartner, Thomas Eiter, ...
Abstract — The Semantic Web vision of a next generation Web, in which machines are enabled to understand the meaning of information in order to better interoperate and better support humans in...
Dr. Thomas Eiter, Wolfgang Faber
Answer Set Programming (ASP) hat sich in den letzten Jahren zu einer
Table of Contents Foundations of Rule-Based Query Answering........................ 1 (2008)
François Bry, Norbert Eisinger, Thomas Eiter, Tim Furche, Georg Gottlob, Clemens Ley, ...
Oracle File System Translator (2008)
Simona Citrigno, Thomas Eiter, Wolfgang Faber, Georg Gottlob, Christoph Koch, Nicola Leone, ...
During the last years, much research has been done concerning semantics and complexity of Disjunctive Deductive Databases (DDDBs). While DDDBs — function-free disjunctive logic programs with...
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer
Most recently, Answer Set Programming (ASP) has been attracting interest as a new paradigm for problem solving. An important aspect, for which several approaches have been presented, is the handling...
A Polynomial-time Algorithm for Constructing k-Maintainable Policies (2008)
In this paper we present a polynomial time algorithm for constructing k-maintainable policies (Nakamura, Baral, & Bjareland 2000). Our algorithm, in polynomial time, constructs a k-maintainable...
FDNC: Decidable Nonmonotonic Disjunctive Logic Programs with Function Symbols (2008)
Ab Wissensbasierte Systeme, Mantas Simkus, Thomas Eiter, Mantas ˇ Simkus, Thomas Eiter
R e s e a r c h R e p o r t
Semantic forgetting in answer set programming (2008)
The notion of forgetting, also known as variable elimination, has been investigated extensively in the context of classical logic, but less so in (nonmonotonic) logic programming and nonmonotonic...
Semantic forgetting in answer set programming (2008)
The notion of forgetting, also known as variable elimination, has been investigated extensively in the context of classical logic, but less so in (nonmonotonic) logic programming and nonmonotonic...
DEFAULT REASONING FROM CONDITIONAL KNOWLEDGE BASES: COMPLEXITY AND TRACTABLE CASES (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
www.kr.tuwien.ac.at
New Tractable Cases in Default Reasoning from Conditional Knowledge Bases (2007)
Thomas Eiter, Thomas Lukasiewicz
Abstract. We present new tractable cases for default reasoning from conditional knowledge bases. In detail, we introduce q-Horn conditional knowledge bases, which allow for a limited use of...
Complexity Results Eigenvector, Yuri Gurevich, Thomas Eiter, Thomas Eiter, Thomas Eiter, ...
logic over strings. Journal of the ACM, 47(1):77-131, 2000.
On Satisfiability of Partially Defined Double and Bidual Horn Functions (extended abstract) (2007)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
Introduction A partially defined Boolean function (pdBF) is a natural generalization of the familiar concept of Boolean function, by allowing that the function value on some vectors is unknown [5]....
Thomas Eiter, Michael Fink, Gianluigi Greco, Domenico Lembo
Abstract. Many data integration systems provide transparent access to heterogeneous data sources through a unified view of all data in terms of a global schema, which may be equipped with integrity...
Transforming co-NP Checks to Answer Set Computation by Meta-Interpretation (2007)
Abstract. Many NP-complete problems can be encoded in the answer set semantics of logic programs in a very concise way, where the encoding re ects the typical \guess and check " nature of NP...
THE DLV SYSTEM FOR KNOWLEDGE REPRESENTATION AND REASONING (2007)
Abtg Wissensbasierte Systeme, Georg Gottlob, Christoph Koch, Cristinel Mateis, Simona Perri, Francesco Scarcello, ...
2
Thomas Eiter, Nicola Leone, David Pearce
Generalising the ideas of [10] we define a simple extension of the notion of unfounded set, called assumption set, that applies to disjunctive logic programs with strong negation. We show that...
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer
Most recently, Answer Set Programming (ASP) has been attracting interest as a new paradigm for problem solving. An important aspect, for which several approaches have been presented, is the handling...
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
In Part I of this series of papers, we have proposed a new logic-based planning language, called K. This language facilitates the description of transitions between states of knowledge and it is well...
Abtg Wissensbasierte Systeme, Generating All Abductive, Thomas Eiter, Thomas Eiter, Kazuhisa Makino, Kazuhisa Makino
www.kr.tuwien.ac.at
Reinhard Pichler, Hypergraphs Acyclicity, Nicola Leone, Francesco Buccafurri, Thomas Eiter, Georg Gottlob, ...
ACTL formulas having linear counterexamples. JCSS, 62(3):463-515, 2001.
CAUSES AND EXPLANATIONS IN THE STRUCTURAL-MODEL APPROACH: TRACTABLE CASES (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
Abstract. In this paper, we continue our research on the algorithmic aspects of Halpern and Pearl’s causes and explanations in the structural-model approach. To this end, we present new...
NEW RESULTS ON MONOTONE DUALIZATION AND GENERATING HYPERGRAPH TRANSVERSALS (2007)
Abtg Wissensbasierte Systeme, Hypergraph Transversals, Kazuhisa Makino, Thomas Eiter, Thomas Eiter, Georg Gottlob, ...
2 and Kazuhisa Makino 3 Abstract. We consider the problem of dualizing a monotone CNF (equivalently, computing all minimal transversals of a hypergraph), whose associated decision problem is a...
NONMONOTONIC KNOWLEDGE BASES (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Giuliana Sabbatini, ...
www.kr.tuwien.ac.at
V. S. Subrahmanian, Piero Bonatti, Thomas Eiter, Sarit Kraus, Robert Ross
Bar-Ilan University
Thomas Eiter, Nicola Leone, Cristinel Mateis, Gerald Pfeifer, Francesco Scarcello
Abstract. dlv is a deductive database system, based on disjunctive logic programming, which offers front-ends to several advanced KR formalisms. The system has been developed since the end of 1996 at...
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
We consider the problem of dualizing a Boolean function f given by CNF, i.e., computing a CNF for its dual f d. While this problem is not solvable in quasi-polynomial total time in general (unless...
Thomas Eiter, Daniel Veit, Jorg P. Muller, Martin Schneider
Abstract A fundamental task in multi-agent systems is matchmaking, which is to retrieve and classify service descriptions of agents that (best) match a given service request. Several approaches to...
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
, which extends the declarative planning language K by action costs and optimal plans that minimize overall action costs (cheapest plans). As shown, this novel language allows for expressing some...
INFORMATION SITE SELECTION (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Hans Tompits, ...
Abstract. With the World Wide Web, a vast number of information sources has become available. In order to access and process these data, suitable tools and methods for building an information...
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
Model-based reasoning has been proposed as an alternative form of representing and accessing logical knowledge bases. In this approach, a knowledge base is represented by a set of characteristic...
COMPLEXITY OF NESTED CIRCUMSCRIPTION AND NESTED ABNORMALITY THEORIES (2007)
Abtg Wissensbasierte Systeme, Marco Cadoli, Marco Cadoli, Thomas Eiter, Thomas Eiter, Georg Gottlob, ...
www.kr.tuwien.ac.at
Discrete Applied Mathematics, 96-97:55--88, 1999. Bidual Horn Functions and Extensions (2007)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
Partially defined Boolean functions (pdBf) (T; F), where T; F f0; 1g n are disjoint sets of true and false vectors, generalize total Boolean functions by allowing that the function values on some...
Journal of the ACM, to appear. Existential Second-Order Logic over Strings (2007)
Thomas Eiter, Georg Gottlob, Yuri Gurevich
Existential second-order logic (ESO) and monadic second-order logic (MSO) have attracted much interest in logic and computer science. ESO is a much more expressive logic over successor structures...
Francesco Buccafurri, Thomas Eiter, Georg Gottlob, Nicola Leone
In case an ACTL formula fails over a transition graph M, it is most useful to provide a counterexample, i.e., a computation tree of M witnessing the failure. If there exists a single path in M which...
REASONING ABOUT EVOLVING NONMONOTONIC KNOWLEDGE BASES (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Giuliana Sabbatini, ...
1 Abstract. Recently, several approaches to updating knowledge bases modeled as extended logic programs have been introduced, ranging from basic methods to incorporate (sequences of) sets of rules...
Thomas Eiter, V. S. Subrahmanian
Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various situations...
Abteilung fur Datenbanken und AI (2007)
We study the complexity of data disjunctions in disjunctive deductive databases (DDDBs), i.e., minimal clauses R(c 1) \Delta \Delta \Delta R(c k), k 2, derived from the database in which all atoms...
1 Comparing Environments for Developing Software Agents (2007)
Thomas Eiter, Viviana Mascardi
In the last years, dozens of environments for modeling, testing and finally implementing multi-agent systems have been developed. Unfortunately, no standard criteria for understanding what kind of...
ANSWER SET PLANNING UNDER ACTION COSTS (2007)
Abtg Wissensbasierte Systeme, Axel Polleres, Thomas Eiter, Thomas Eiter, Wolfgang Faber, Wolfgang Faber, ...
, Axel Polleres 1 Abstract.More recently, planning based on answer set programming has been proposed as an approach towards realizing declarative planning systems. In this paper, we present the...
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
, which extends the declarative planning language K by action costs and optimal plans that minimize overall action costs (cheapest plans). As shown, this novel language allows for expressing some...
Complexity of Nested Circumscription and Abnormality Theories (2007)
Marco Cadoli, Thomas Eiter, Georg Gottlob
We propose L Circ, an extension of circumscription by allowing propositional combinations and nesting of circumscriptive theories. As shown, Lifschitz 's nested abnormality theories (NATs,...
Evgeny Dantsin, Thomas Eiter, Georg Gottlob, Andrei Voronkov
This paper surveys various complexity results on different forms of logic programming. The main focus is on decidable forms of logic programming, in particular, propositional logic programming and...
Thomas Eiter, Nicola Leone, Domenico Sacc A
Partial stable models for deductive databases, i.e., normal function-free logic programs (also called datalog programs), have two equivalent definitions: one based on 3-valued logics and another...
Thomas Eiter, Viviana Mascardi, V. S. Subrahmanian
Abstract The use of agents in today's Internet world is expanding rapidly. Yet, agent developers proceed largely under the optimistic assumption that agents will be error-free. Errors may arise...
Running head: On the Dierence of Horn Theories Mailing address: (2007)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino, Kazuhisa Makino
In this paper, we consider computing the dierence between two Horn theories. This problem may arise, for example, if we take care of a theory change in a knowledge base. In general, the dierence of...
This paper addresses complexity issues for important problems arising with disjunctive logic programming. In particular, the complexity of deciding whether a disjunctive logic program is consistent...
On the Difference of Horn Theories (Extended Abstract) (2007)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
Abstract. In this paper, we consider computing the difference between two Horn theories. This problem may arise, for example, if we take care of a theory change in a knowledge base. In general, the...
COMPLEXITY RESULTS FOR EXPLANATIONS IN THE STRUCTURAL-MODEL APPROACH (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
Abstract. We analyze the computational complexity of Halpern and Pearl's (causal) explanations in the structural-model approach, which are based on their notions of weak and actual causality. In...
Siam Journal on Computing, 31(1):269-288, 2001. Disjunctions of Horn Theories and their Cores (2007)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
In this paper, we study issues on disjunctions of propositional Horn theories. In particular, we consider the problems of deciding whether a disjunction of Horn theories is Horn, and, if not,...
A LOGIC PROGRAMMING APPROACH TO KNOWLEDGE-STATE PLANNING: SEMANTICS AND COMPLEXITY (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres, ...
Abstract. We propose a new declarative planning language, called K, which is based on principles and methods of logic programming. In this language, transitions between states of knowledge can be...
A LOGIC PROGRAMMING APPROACH TO KNOWLEDGESTATE PLANNING, II: THE DLV (2007)
Abtg Wissensbasierte Systeme, Nicola Leone, Gerald Pfeifer, Axel Polleres, Thomas Eiter, Thomas Eiter, ...
Abstract. In Part I of this series of papers, we have proposed a new logic-based planning language, called K. This language facilitates the description of transitions between states of knowledge and...
COMPUTING PREFERRED ANSWER SETS BY META-INTERPRETATION IN ANSWER SET PROGRAMMING (2007)
Abtg Wissensbasierte Systeme, Nicola Leone, Gerald Pfeifer, Thomas Eiter, Thomas Eiter, Wolfgang Faber, ...
1, Nicola Leone 2, Gerald Pfeifer 3 Abstract. Most recently, Answer Set Programming (ASP) is attracting interest as a new paradigm for problem solving. An important aspect which needs to be supported...
Theoretical Computer Science, to appear. Decision Lists and Related Boolean Functions ;y (2007)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
We consider Boolean functions represented by decision lists, and study their relationships to other classes of Boolean functions. It turns out that the elementary class of 1-decision lists has...
We consider the computation of eigenvectors x = (x 1; : : : ; xn) over the integers, where each component x i satisfies jx i j b for an integer b. We address various problems in this context, and...
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
Abstract. A partially dened Boolean function (pdBf) (T; F) generalizes a Boolean function, by allowing that the function values on some inputs are unknown, where T; F f0; 1g n are disjoint sets of...
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
Abstract. In this paper, we study issues on disjunctions of propositional Horn theories. In particular, we consider deciding whether a disjunction of Horn theories is Horn, and, if not, computing a...
Acta Informatica, 32(2):117-187, 1995. Generating Boolean -Expressions (2007)
In this paper, we consider the class of Boolean -functions, which are the Boolean functions denable by -expressions (Boolean expressions in which no variable occurs more than once). We present an...
USING METHODS OF DECLARATIVE LOGIC PROGRAMMING FOR INTELLIGENT INFORMATION AGENTS (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Giuliana Sabbatini, ...
www.kr.tuwien.ac.at
COMPLEXITY AND EXPRESSIVE POWER OF LOGIC PROGRAMMING (2007)
Abtg Wissensbasierte Systeme, Georg Gottlob, Thomas Eiter, Andrei Voronkov, Evgeny Dantsin, Evgeny Dantsin
1 Thomas Eiter, 2 Georg Gottlob, 3 Andrei Voronkov 4 Abstract. This paper surveys various complexity and expressiveness results on different forms of logic programming. The main focus is on decidable...
COMPARING ENVIRONMENTS FOR DEVELOPING SOFTWARE AGENTS (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Viviana Mascardi, Viviana Mascardi
2 Abstract. In the last years, dozens of environments for modeling, testing and finally implementing multi-agent systems have been developed. Unfortunately, no standard criteria for understanding...
PROBABILISTIC OBJECT BASES (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz, James J. Lu, ...
2 V.S. Subrahmanian 3 Abstract. Though there are many applications where an object oriented data model is a good way of representing and querying data, current object database systems are unable to...
COMPLEXITY RESULTS FOR STRUCTURE-BASED CAUSALITY (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
Abstract. We analyze the computational complexity of causal relationships in Pearl's structural models, where we focus on causality between variables, event causality, and probabilistic...
Heterogeneous Active Agents, I: Semantics (2007)
Abtg Wissensbasierte Systeme, George Pick, Thomas Eiter, Thomas Eiter, V. S. Subrahmanian, V. S. Subrahmanian
www.kr.tuwien.ac.at
Heterogeneous Active Agents, II: Algorithms and Complexity (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, V. S. Subrahmanian, V. S. Subrahmanian
2 Abstract. In Part I of this series of papers, we developed a language called Agent Programs for defining the operational behavior of software agents and defined a set of successively more...
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Viviana Mascardi, Viviana Mascardi, V. S. Subrahmanian, ...
Abstract. The use of agents in today's Internet world is expanding rapidly. Yet, agent developers proceed largely under the optimistic assumption that agents will be error-free. Errors may arise...
ON ACTL FORMULAS HAVING DETERMINISTIC COUNTEREXAMPLES (2007)
Abtg Wissensbasierte Systeme, Georg Gottlob, Nicola Leone, Francesco Buccafurri, Francesco Buccafurri, Thomas Eiter, ...
3 Nicola Leone 3 Abstract. In case an ACTL formula OE fails over a labeled transition graph M, it is most useful to provide a counterexample, i.e., a computation tree of M witnessing the failure. If...
I N F S Y S R E S E a R C H (2007)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
We give a precise picture of the computational complexity of causal relationships in Pearl's structural models, where we focus on causality between variables, event causality, and probabilistic...
CHECK PROGRAMS IN ANSWER SET PROGRAMMING: A META-INTERPRETER AND APPLICATIONS (2007)
Ag Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Axel Polleres, Axel Polleres
www.kr.tuwien.ac.at
Chapter 4 DECLARATIVE PROBLEM-SOLVING USING THE DLV SYSTEM (2007)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer
Abstract The need for representing indefinite information led to disjunctive deductive databases, which also fertilized work on disjunctive logic programming. Based on this paradigm, the DLV system...
Springer. Abduction and the Dualization Problem (2007)
Abstract. Computing abductive explanations is an important problem, which has been studied extensively in Artificial Intelligence (AI) and related disciplines. While computing some abductive...
Foundations of rule-based query answering (2007)
François Bry, Norbert Eisinger, Thomas Eiter, Tim Furche, Georg Gottlob, Clemens Ley, ...
Abstract. This survey article introduces into the essential concepts and methods underlying rule-based query languages. It covers four complementary areas: declarative semantics based on adaptations...
DATA COMPLEXITY OF QUERY ANSWERING IN EXPRESSIVE DESCRIPTION LOGICS VIA TABLEAUX (2007)
Ab Wissensbasierte Systeme, Magdalena Ortiz, Diego Calvanese, Thomas Eiter, Magdalena Ortiz, Diego Calvanese, ...
Abstract. The logical foundations of the standard web ontology languages are provided by expressive Description Logics (DLs), such as SHIQ and SHOIQ. In the Semantic Web and other domains, ontologies...
REPAIR LOCALIZATION FOR QUERY ANSWERING FROM INCONSISTENT DATABASES (2007)
Ab Wissensbasierte Systeme, Thomas Eiter, Michael Fink, Gianluigi Greco, Domenico Lembo, Thomas Eiter, ...
Abstract. Query answering from inconsistent databases amounts to finding “meaningful ” answers to queries posed over database instances that do not satisfy integrity constraints specified over...
COMBINING ANSWER SET PROGRAMMING WITH DESCRIPTION LOGICS FOR THE SEMANTIC WEB (2007)
Ag Wissensbasierte Systeme, Thomas Eiter, Giovambattista Ianni, Thomas Lukasiewicz, Roman Schindlauer, Hans Tompits, ...
Roman Schindlauer1 Hans Tompits1 Abstract. We propose a combination of logic programming under the answer set semantics with the description logics SHIF(D) and SHOIN(D), which underly the Web...
SEMANTIC FORGETTING IN ANSWER SET PROGRAMMING (2007)
Ab Wissensbasierte Systeme, Thomas Eiter, Kewen Wang, Thomas Eiter, Kewen Wang
Abstract. The notion of forgetting, also known as variable elimination, has been investigated extensively in the context of classical logic, but less so in (nonmonotonic) logic programming and...
Embedding non-ground logic programs into autoepistemic logic for knowledge-base combination (2007)
Jos De Bruijn, Thomas Eiter, Axel Polleres, Hans Tompits
In the context of the Semantic Web, several approaches to the combination of ontologies, given in terms of theories of classical first-order logic, and rule bases have been proposed. They either cast...
A Knowledge-Based Approach for Selecting Information Sources (2006)
Eiter, Thomas, Fink, Michael, Tompits, Hans
Through the Internet and the World-Wide Web, a vast number of information sources has become available, which offer information on various subjects by different providers, often in heterogeneous...
Forgetting and Conflict Resolving in Disjunctive Logic Programming (2006)
Eiter, Thomas, Wang, Kewen, Yolanda Gil
Yes
LPForget: A system of forgetting in answer set programming (2006)
Cheng, Fu-Leung, Eiter, Thomas, Robinson, Nathan Mark, Sattar, Abdul, Wang, Kewen
Yes
Forgetting in Managing Rules and Ontologies (2006)
Eiter, Thomas, Ianni, Giovambattista, Schindlauer, Roman, Tompits, Hans, Wang, Kewen
The language of HEX-programs under the answer-set semantics is designed for interoperating with heterogeneous sources via external atoms and for meta-reasoning via higher-order literals in the...
LPForget: A system of forgetting in answer set programming (2006)
Cheng, Fu-Leung, Eiter, Thomas, Robinson, Nathan Mark, Sattar, Abdul, Wang, Kewen
Forgetting in Managing Rules and Ontologies (2006)
Eiter, Thomas, Ianni, Giovambattista, Schindlauer, Roman, Tompits, Hans, Wang, Kewen
The language of HEX-programs under the answer-set semantics is designed for interoperating with heterogeneous sources via external atoms and for meta-reasoning via higher-order literals in the...
Answer set programming for the semantic web (2006)
Thomas Eiter, Thomas Eiter, Giovambattista Ianni, Axel Polleres, Roman Schindlauer
Abstract. The purpose of this tutorial is to get the audience familiar with the Answer Set Programming (ASP) Paradigm in the perspective of its fruitful usage for Semantic Web applications. ASP is a...
Reasoning with rules and ontologies (2006)
Thomas Eiter, Giovambattista Ianni, Axel Polleres, Roman Schindlauer, Hans Tompits
Abstract. For realizing the Semantic Web vision, extensive work is underway for getting the layers of its conceived architecture ready. Given that the Ontology Layer has reached a certain level of...
Exploiting conjunctive queries in description logic programs (2006)
Thomas Eiter, Giovambattista Ianni, Thomas Krennwallner, Roman Schindlauer
Abstract. We present cq-programs, which enhance nonmonotonic description logics (dl-) programs by conjunctive queries (CQ) and union of conjunctive queries (UCQ) over Description Logics knowledge...
Forgetting in managing rules and ontologies (2006)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
The language of HEX-programs under the answer-set semantics is designed for interoperating with heterogeneous sources via external atoms and for meta-reasoning via higher-order literals in the...
Magdalena Ortiz, Diego Calvanese, Thomas Eiter
Description Logics (DLs) are the formal foundations of the standard web ontology languages OWL-DL and OWL-Lite. In the Semantic Web and other domains, ontologies are increasingly seen also as a...
dlvhex: A system for integrating multiple semantics in an answer-set programming framework (2006)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
Abstract. We briefly report on the development status of dlvhex, a reasoning engine for HEX-prog-rams, which are nonmonotonic logic programs with higher-order atoms and external atoms. Higherorder...
Replacements in non-ground answer-set programming (2006)
Thomas Eiter, Michael Fink, Hans Tompits, Patrick Traxler, Stefan Woltran
Replacements in non-ground answer-set programming (2006)
Thomas Eiter, Michael Fink, Hans Tompits, Patrick Traxler, Stefan Woltran
In this paper, we propose a formal framework for specifying rule replacements in nonmonotonic logic programs within the answer-set programming paradigm. Of particular interest are replacement schemas...
Forgetting in managing rules and ontologies (2006)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
The language of HEX-programs under the answer-set semantics is designed for interoperating with heterogeneous sources via external atoms and for meta-reasoning via higher-order literals in the...
Forgetting and conflict resolving in disjunctive logic programming (2006)
We establish a declarative theory of forgetting for disjunctive logic programs. The suitability of this theory is justified by a number of desirable properties. In particular, one of our results...
COMPARING ACTION DESCRIPTIONS BASED ON SEMANTIC PREFERENCES (2006)
Ab Wissensbasierte Systeme, Thomas Eiter, Esra Erdem, Michael Fink, Ján Senko, Thomas Eiter, ...
Abstract. We consider action domain descriptions whose meaning can be represented by transition diagrams. We introduce several semantic measures to compare such action descriptions, based on...
COMPUTATIONAL ASPECTS OF MONOTONE DUALIZATION: A BRIEF SURVEY (2006)
Ab Wissensbasierte Systeme, Thomas Eiter, Kazuhisa Makino, Georg Gottlob, Thomas Eiter, Kazuhisa Makino, ...
Abstract.Dualization of a monotone Boolean function represented by a conjunctive normal form (CNF) is a problem which, in different disguise, is ubiquitous in many areas including Computer Science,...
DATA COMPLEXITY OF QUERY ANSWERING IN EXPRESSIVE DESCRIPTION LOGICS WITH NOMINALS (2006)
Ab Wissensbasierte Systeme, M. Magdalena, Ortiz Diego, Calvanese Thomas Eiter, M. Magdalena Ortiz, Diego Calvanese, ...
Abstract. The formal foundations of the standard web ontology languages, OWL-Lite and OWL-DL, are provided by expressive Description Logics (DLs), such as SHIF and SHOIQ. In the Semantic Web and...
Undoing the effects of action sequences (2006)
Thomas Eiter, Esra Erdem, Wolfgang Faber
Thomas Eiter1 Esra Erdem2 Wolfgang Faber3 Abstract. When an agent has executed a single action or a sequence of actions, it maysometimes be desirable that the effects of this execution are undone and...
Data complexity of answering unions of conjunctive queries in SHIQ (2006)
Magdalena Ortiz, Diego Calvanese, Thomas Eiter
The novel context of accessing and querying large data repositories through ontologies that are formalized in terms of expressive DLs requires on the one hand to consider query answering as the...
Resolving conflicts in action descriptions (2006)
Thomas Eiter, Esra Erdem, Michael Fink, Ján Senko
Abstract. We study resolving conflicts between an action description and a set of conditions (possibly obtained from observations), in the context of action languages. In this formal framework, the...
Forgetting and conflict resolving in disjunctive logic programming (2006)
We establish a declarative theory of forgetting for disjunctive logic programs. The suitability of this theory is justified by a number of desirable properties. In particular, one of our results...
Supervised Dr, Diego Calvanese, Dr. Thomas Eiter
2003–2004 Universidad de las Américas, Puebla.
Thomas Eiter, Esra Erdem, Michael Fink, Ján Senko
Abstract. We consider action domain descriptions whose meaning can be represented by transition diagrams. We introduce several semantic measures to compare such action descriptions, based on...
Resolving conflicts in action descriptions (2006)
Thomas Eiter, Esra Erdem, Michael Fink, Ján Senko
We study the problem of resolving conflicts between an action description and a set of conditions (possibly obtained from observations), in the context of action languages. In this formal framework,...
dlvhex: A system for integrating multiple semantics in an answer-set programming framework (2006)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
Abstract. We briefly report on the development status of dlvhex, a reasoning engine for HEX-programs, which are nonmonotonic logic programs with higher-order atoms and external atoms. Higherorder...
Data complexity of answering unions of conjunctive queries in SHIQ (2006)
Magdalena Ortiz, Diego Calvanese, Thomas Eiter
The novel context of accessing and querying large data repositories through ontologies that are formalized in terms of expressive DLs, requires on the one hand to consider query answering as the...
LPForget: A system of forgetting in answer set programming (2006)
Cheng, Fu-Leung, Eiter, Thomas, Robinson, Nathan Mark, Sattar, Abdul, Wang, Kewen
Forgetting in Managing Rules and Ontologies (2006)
Eiter, Thomas, Ianni, Giovambattista, Schindlauer, Roman, Tompits, Hans, Wang, Kewen
The language of HEX-programs under the answer-set semantics is designed for interoperating with heterogeneous sources via external atoms and for meta-reasoning via higher-order literals in the...
04171 Abstracts Collection -- Logic Based Information Agents (2006)
Dix, Jürgen, Eiter, Thomas, Franconi, Enrico
From 18.04.04 to 23.04.04, the Dagstuhl Seminar 04171 ``Logic Based Information Agents'' was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar,...
Forgetting in managing rules and ontologies (2006)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits, Kewen Wang
Abstract. The language of HEX-programs under the answer-set semantics is designed for interoperating with heterogeneous sources via external atoms and for meta-reasoning via higher-order literals in...
Forgetting and Conflict Resolving in Disjunctive Logic Programming (2006)
We establish a declarative theory of forgetting for disjunctive logic programs. The suitability of this theory is justified by a number of desirable properties. In particular, one of our results...
Data complexity of answering conjunctive queries over SHIQ knowledge bases (2005)
Calvanese, Diego, Eiter, Thomas, Franconi, Enrico
An algorithm for answering conjunctive queries over SHIQ knowledge bases that is coNP in data complexity is given. The algorithm is based on the tableau algorithm for reasoning with individuals in...
Semantical Characterizations and Complexity of Equivalences in Answer Set Programming (2005)
Eiter, Thomas, Fink, Michael, Woltran, Stefan
In recent research on non-monotonic logic programming, repeatedly strong equivalence of logic programs P and Q has been considered, which holds if the programs P union R and Q union R have the same...
Answer set programming (ASP) with disjunction offers a powerful tool for declaratively representing and solving hard problems. Many NP-complete problems can be encoded in the answer set semantics of...
On Solution Correspondences in Answer Set Programming (2005)
Thomas Eiter, Hans Tompits, Stefan Woltran
We introduce a general framework for specifying program correspondence under the answer-set semantics. The framework allows to define different kinds of equivalence notions, including previously...
H.: DLV-HEX: Dealing with Semantic Web under Answer-Set Programming (2005)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
We present an implementation of HEX programs, which are nonmonotonic logic programs admitting higher-order atoms as well as external atoms. Higher-order features are widely acknowledged as useful for...
Updating action domain descriptions (2005)
Thomas Eiter, Esra Erdem, Michael Fink, Ján Senko
How can an intelligent agent update her knowledge base about an action domain, relative to some conditions (possibly obtained from earlier observations)? We study this question in a formal framework...
Semantical Characterizations and Complexity of Equivalences in Answer Set Programming (2005)
Thomas Eiter, Michael Fink, Stefan Woltran
In recent research on nonmonotonic logic programming, repeatedly strong equivalence of logic programs P and Q has been considered, which holds if the programs P ∪ R and Q ∪ R have the same answer...
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
We introduce HEX programs, which are nonmonotonic logic programs admitting higher-order atoms as well as external atoms, and we extend the wellknown answer-set semantics to this class of programs....
Thomas Eiter, Michael Fink, Hans Tompits
Through the Internet and the World-Wide Web, a vast number of information sources has become available, which offer information on various subjects by different providers, often in heterogeneous...
Data integration and answer set programming (2005)
Abstract. The rapid expansion of the Internet and World Wide Web led to growing interest in data and information integration, which should be capable to deal with inconsistent and incomplete data....
CAUSES AND EXPLANATIONS IN THE STRUCTURAL-MODEL APPROACH: TRACTABLE CASES (2005)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Lukasiewicz, Thomas Eiter, Thomas Lukasiewicz
Abstract. This paper continues the research on the computational aspects of Halpern and Pearl’s causes and explanations in the structural-model approach. To this end, we first explore how an...
Testing strong equivalence of datalog programs: Implementation and examples (2005)
Thomas Eiter, Wolfgang Faber, Patrick Traxler
Abstract. In this work we describe a system for determining strong equivalence of disjunctive non-ground datalog programs under the stable model semantics. The problem is tackled by reducing it to...
REASONING UNDER MINIMAL UPPER BOUNDS IN PROPOSITIONAL LOGIC (2005)
Ab Wissensbasierte Systeme, Thomas Eiter, Georg Gottlob, Thomas Eiter, Georg Gottlob
Abstract. Reasoning from the minimal models of a theory, as fostered by circumscription, is in the area of Artificial Intelligence an important method to formalize common sense reasoning. However, as...
Abtg Wissensbasierte Systeme, Thomas Eiter, Michael Fink, Gianluigi Greco, Domenico Lembo, Thomas Eiter, ...
Abstract. Information integration systems providing the user with transparent access to heterogeneous data sources through a unified global view of all data, have emerged as a crucial issue in many...
Thomas Eiter, Michael Fink, Stefan Woltran, Thomas Eiter, Michael Fink, Stefan Woltran
Abstract. In recent research on non-monotonic logic programming, repeatedly strong equivalence of logic programs P and Q has been considered, which holds if the programs P ∪ R and Q ∪ R have the...
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
We introduce HEX programs, which are nonmonotonic logic programs admitting higher-order atoms as well as external atoms, and we extend the wellknown answer-set semantics to this class of programs....
Nonmonotonic Description Logic Programs: Implementation and Experiments (2005)
Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, Hans Tompits
Abstract. The coupling of description logic reasoning systems with other reasoning formalisms (possibly over the Web) is becoming an important research issue and calls for advanced methods and...
The infomix system for advanced integration of incomplete and inconsistent data (2005)
Nicola Leone, Gianluigi Greco, Giovambattista Ianni, Vincenzino Lio, Giorgio Terracina, Thomas Eiter, ...
The task of an information integration system is to combine data residing at different sources, providing the user with a unified view of them, called global schema. Users formulate queries over the...
Thomas Eiter, Michael Fink, Hans Tompits, Stefan Woltran
Recent research in nonmonotonic logic programming under the answer-set semantics studies different notions of equivalence. In particular, strong and uniform equivalence are proposed as useful tools...
On Eliminating Disjunctions in Stable Logic Programming (2004)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Hans Tompits, ...
Abstract. Disjunction is generally considered to add expressive power to logic programs under the stable model semantics, which have become a popular programming paradigm for knowledge representation...
Thomas Eiter, Wolfgang Faber, Michael Fink, Gerald Pfeifer
Answer Set Programming has become a host for expressing knowledge representation problems, which reinforces the interest in efficient methods for computing answer sets of a logic program. While for...
Simplifying logic programs under uniform and strong equivalence (2004)
Thomas Eiter, Michael Fink, Hans Tompits, Stefan Woltran
Abstract. We consider the simplification of logic programs under the stablemodel semantics, with respect to the notions of strong and uniform equivalence between logic programs, respectively. Both...
Reasoning about evolving nonmonotonic knowledge bases (2004)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
Abstract. Recently, several approaches to updating knowledge bases modeled as extended logic programs (ELPs) have been introduced, ranging from basic methods to incorporate (sequences of) sets of...
Thomas Eiter, Wolfgang Faber, Michael Fink, Gerald Pfeifer, Stefan Woltran
Answer Set Programming has become a host for expressing knowledge representation problems, which reinforces the interest in efficient methods for computing answer sets of a logic program. While for...
Towards Automated Integration of Guess and Check Programs in Answer Set Programming (2004)
Many NP-complete problems can be encoded in the answer set semantics of logic programs in a very concise way, where the encoding reflects the typical "guess and check" nature of NP...
Combining Answer Set Programming with Description Logics for the Semantic Web (2004)
Thomas Eiter, Thomas Lukasiewicz, Roman Schindlauer, Hans Tompits
Towards the integration of rules and ontologies in the Semantic Web, we propose a combination of logic programming under the answer set semantics with the description (D), which underly the Web...
Thomas Eiter, Wolfgang Faber, Michael Fink, Gerald Pfeifer, Stefan Woltran
We present new complexity results on answer set checking for nonground programs under a variety of syntactic restrictions. For several of these problems, the kind of representation of the answer set...
Reasoning Methods for Personalization on the Semantic Web (2004)
Grigoris Antoniou, Matteo Baldoni, Cristina Baroglio, Viviana Patti, Robert Baumgartner, Thomas Eiter, ...
The Semantic Web vision of a next generation Web, in which machines are enabled to understand the meaning of information in order to better interoperate and better support humans in carrying out...
On Eliminating Disjunctions in Stable Logic Programming (2004)
Thomas Eiter, Michael Fink, Hans Tompits, Stefan Woltran
Disjunction is generally considered to add expressive power to logic programs under the stable model semantics, which have become a popular programming paradigm for knowledge representation and...
Thomas Eiter, Wolfgang Faber, Michael Fink, Gerald Pfeifer, Stefan Woltran
We present new complexity results on answer set checking for nonground programs under a variety of syntactic restrictions. For several of these problems, the kind of representation of the answer set...
Simplifying Logic Programs under Uniform and Strong Equivalence (2004)
Thomas Eiter, Michael Fink, Hans Tompits, Stefan Woltran
We consider the simplification of logic programs under the stablemodel semantics, with respect to the notions of strong and uniform equivalence between logic programs, respectively. Both notions have...
DIAGNOSING PLAN EXECUTION DISCREPANCIES IN (2004)
Executio Nd, Iscrepancies In, A Logic-baseda, Thomas Eiter, Esra Erdem, ...
MAINTENANCE GOALS OF AGENTS IN A DYNAMIC ENVIRONMENT: FORMULATION AND POLICY CONSTRUCTION (2004)
Ab Wissensbasierte Systeme, Chitta Baral, Thomas Eiter, Marcus Bjäreland, Mutsumi Nakamura, Chitta Baral, ...
Abstract.The notion of maintenance often appears in the AI literature in the context of agent behavior and planning. In this paper, we argue that earlier characterizations of the notion of...
Plan Reversals for Recovery in Execution Monitoring (2004)
Thomas Eiter, Esra Erdem, Wolfgang Faber
In this paper, we introduce a new method to recover from discrepancies in a general monitoring framework where the agent finds some explanations (points of failure) for discrepancies. According to...
Thomas Eiter, Wolfgang Faber, Michael Fink, Gerald Pfeifer
Answer Set Programming has become a host for expressing knowledge representation problems, which reinforces the interest in efficient methods for computing answer sets of a logic program. While for...
COMBINING ANSWER SET PROGRAMMING WITH DESCRIPTION LOGICS FOR THE SEMANTIC WEB (2004)
Ab Wissensbasierte Systeme, Thomas Eiter, Thomas Lukasiewicz, Roman Schindlauer, Hans Tompits, Thomas Eiter, ...
Abstract. Towards the integration of rules and ontologies in the Semantic Web, we propose a combination of logic programming under the answer set semantics with the description logics SHIF(D) and...
Plan Reversals for Recovery in Execution Monitoring (2004)
Thomas Eiter, Esra Erdem, Wolfgang Faber
In this paper, we introduce a new method to recover from discrepancies in a general monitoring framework where the agent finds some explanations (points of failure) for discrepancies. According to...
Well-founded semantics for description logic programs in the semantic web (2004)
Thomas Eiter, Thomas Lukasiewicz, Roman Schindlauer, Hans Tompits
Abstract. In previous work, towards the integration of rules and ontologies in the Semantic Web, we have proposed a combination of logic programming under the answer set semantics with the...
Towards automated integration of guess and check programs in answer set programming (2004)
Abstract. Many NP-complete problems can be encoded in the answer set semantics of logic programs in a very concise way, where the encoding reflects the typical “guess and check ” nature of NP...
Combining answer set programming with description logics for the Semantic Web (2004)
Thomas Eiter, Thomas Lukasiewicz
Towards the integration of rules and ontologies in the Semantic Web, we propose a combination of logic programming under the answer set semantics with the description logics SHIF(D) and SHOIN (D),...
On Eliminating Disjunctions in Stable Logic Programming (2004)
Thomas Eiter, Michael Fink, Hans Tompits, Stefan Woltran
Disjunction is generally considered to add expressive power to logic programs under the stable model semantics, which have become a popular programming paradigm for knowledge representation and...
Plan Reversals for Recovery in Execution Monitoring (2004)
Thomas Eiter, Esra Erdem, Wolfgang Faber
In this paper, we introduce a new method to recover from discrepancies in a general monitoring framework where the agent finds some explanations (points of failure) for discrepancies. According to...
Reasoning about evolving nonmonotonic knowledge bases (2004)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
Abstract. Recently, several approaches to updating knowledge bases modeled as extended logic programs (ELPs) have been introduced, ranging from basic methods to incorporate (sequences of) sets of...
Esra Erdem, Thomas Eiter, Wolfgang Faber
Planning has played an important role in many relevant areas of AI. The classical planning problem consists of the following task: Given a state
Well-founded semantics for description logic programs in the semantic web (2004)
Thomas Eiter, Thomas Lukasiewicz, Roman Schindlauer, Hans Tompits
Abstract. In previous work, towards the integration of rules and ontologies in the Semantic Web, we have proposed a combination of logic programming under the answer set semantics with the...
Probabilistic reasoning about actions in nonmonotonic causal theories (2003)
Thomas Eiter, Thomas Lukasiewicz
We present the language PC+ for probabilistic reasoning about actions, which is a generalization of the action language C+ that allows to deal with probabilistic as well as nondeterministic effects...
Generating all abductive explanations for queries on propositional Horn theories (2003)
Abstract. Abduction is a fundamental mode of reasoning, which has taken on increasing importance in Artificial Intelligence (AI) and related disciplines. Computing abductive explanations is an...
A Knowledge-Based Approach for Selecting Information Sources (2003)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Hans Tompits, ...
Abstract. Through the Internet and the World Wide Web, a vast number of information sources has become available, which offer information on various subjects by different providers, often in...
Answer Set Planning under Action Costs (2003)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
Recently, planning based on answer set programming has been proposed as an approach towards realizing declarative planning systems. In this paper, we present the language extends the declarative...
Eliminating Disjunction from Propositional Logic Programs under Stable Model Preservation (2003)
Thomas Eiter, Michael Fink, Hans Tompits, Stefan Woltran
In general, disjunction is considered to add expressive power to propositional logic programs under stable model semantics, and to enlarge the range of problems which can be expressed. However, from...
Monitoring Agents Using Declarative Planning (2003)
Abtg Wissensbasierte Systeme, Jürgen Dix, Thomas Eiter, Michael Fink, Axel Polleres, Yingqian Zhang, ...
We consider the following problem: Given a particular description of a multi-agent system (MAS), is it implemented properly? We assume we are given (possibly incomplete) information and aim at...
Monitoring Agents Using Declarative Planning (2003)
Jürgen Dix, Thomas Eiter, Michael Fink, Axel Polleres, Yingqian Zhang
We present an agent monitoring approach, which aims at refuting from (possibly incomplete) information at hand that a multi-agent system (MAS) is implemented properly. In this approach, agent...
Probabilistic Reasoning about Actions in Nonmonotonic Causal Theories (2003)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
The action language is an important high-level formalism for describing actions, which has evolved from a number of earlier proposals for action languages, and which is based on McCain and...
Probabilistic reasoning about actions in nonmonotonic causal theories (2003)
We present the language ¡£¢¥¤ for probabilistic reasoning about actions, which is a generalization of the action language ¢¥¤ that allows to deal with probabilistic as well as...
Monitoring Agents Using Declarative Planning (2003)
Jürgen Dix, J Urgen Dix, Thomas Eiter, Michael Fink, Axel Polleres, Yingqian Zhang
In this paper we consider the following problem: Given a particular description of a multi-agent system (MAS), is it implemented properly? We assume that we are given (possibly incomplete)...
Tomhas Eiter, Abtg Wissensbasierte Systeme, Wolfgang Faber, Michael Fink, Stefan Woltran, Thomas Eiter, ...
We present new complexity results on answer set checking for non-ground programs under a variety of syntactic restrictions. For several of these problems, the kind of representation of the answer set...
Uniform Equivalence of Logic Programs under the Stable Model Semantics (2003)
In recent research on nonmonotonic logic programming, repeatedly strong equivalence of logic programs P and Q has been considered, which holds if the programs P [ R and Q [ R have the same stable...
Generating all abductive explanations for queries on propositional Horn theories (2003)
Abstract. Abduction is a fundamental mode of reasoning, which has taken on increasing importance in Artificial Intelligence (AI) and related disciplines. Computing abductive explanations is an...
Uniform Equivalence of Logic Programs under the Stable Model Semantics (2003)
Abstract. In recent research on nonmonotonic logic programming, repeatedly strong equivalence of logic programs P and Q has been considered, which holds if the programs P ∪ R and Q ∪ R have the...
The DLV System for Knowledge Representation and Reasoning (2002)
Leone, Nicola, Pfeifer, Gerald, Faber, Wolfgang, Eiter, Thomas, Gottlob, Georg, Perri, Simona, ...
This paper presents the DLV system, which is widely considered the state-of-the-art implementation of disjunctive logic programming, and addresses several aspects. As for problem solving, we provide...
Complexity of Nested Circumscription and Nested Abnormality Theories (2002)
Cadoli, Marco, Eiter, Thomas, Gottlob, Georg
The need for a circumscriptive formalism that allows for simple yet elegant modular problem representation has led Lifschitz (AIJ, 1995) to introduce nested abnormality theories (NATs) as a tool for...
New Results on Monotone Dualization and Generating Hypergraph Transversals (2002)
Eiter, Thomas, Gottlob, Georg, Makino, Kazuhisa
We consider the problem of dualizing a monotone CNF (equivalently, computing all minimal transversals of a hypergraph), whose associated decision problem is a prominent open problem in...
Computing Preferred Answer Sets by Meta-Interpretation in Answer Set Programming (2002)
Eiter, Thomas, Faber, Wolfgang, Leone, Nicola, Pfeifer, Gerald
Most recently, Answer Set Programming (ASP) is attracting interest as a new paradigm for problem solving. An important aspect which needs to be supported is the handling of preferences between rules,...
The DLV System for Knowledge Representation and Reasoning (2002)
Nicola Leone, Gerald Pfeifer, Wolfgang Faber, Thomas Eiter, Georg Gottlob, Simona Perri, ...
Disjunctive Logic Programming (DLP) is an advanced formalism for knowledge representation and reasoning, which is very expressive in a precise mathematical sense: it allows to express every property...
Answer set planning under action costs (2002)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
Recently, planning based on answer set programming has been proposed as an approach towards realizing declarative planning systems. In this paper, we present the language K c, which extends the...
Thomas Eiter, Viviana Mascardi, V. S. Subrahmanian
Abstract The use of agents in today’s Internet world is expanding rapidly. Yet, agent developers proceed largely under the optimistic assumption that agents will be error-free. Errors may arise in...
New results on monotone dualization and generating hypergraph transversals (2002)
Thomas Eiter, Georg Gottlob, Kazuhisa Makino
We consider the problem of dualizing a monotone CNF (equivalently, computing all minimal transversals of a hypergraph), whose associated decision problem is a prominent open problem in...
Using Methods of Declarative Logic Programming for Intelligent Information Agents (2002)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
At present, the search for specific information on the World Wide Web is faced with several problems, which arise on the one hand from the vast number of information sources available, and on the...
Causes and explanations in the structural-model approach: Tractable cases (2002)
In this paper, we continue our research on the algorithmic aspects of Halpern and Pearl’s causes and explanations in the structural-model approach. To this end, we present new characterizations of...
Modal Nonmonotonic Logics Revisited: Efficient Encodings for the Basic Reasoning Tasks (2002)
Thomas Eiter, Volker Klotz, Hans Tompits, Stefan Woltran
Abstract. Modal nonmonotonic logics constitute a well-known family of knowledge-representation formalisms capturing ideally rational agents reasoning about their own beliefs. Although these...
Causes and explanations in the structural-model approach: Tractable cases (2002)
Thomas Eiter, Thomas Lukasiewicz
In this paper, we continue our research on the algorithmic aspects of Halpern and Pearl's causes and explanations in the structural-model approach. To this end, we present new characterizations...
Complexity results for explanations in the structural-model approach (2002)
Thomas Eiter, Thomas Lukasiewicz
We analyze the computational complexity of Halpern and Pearl's (causal) explanations in the structural-model approach, which are based on their notions of weak and actual causality. In...
A Generic Approach for Knowledge-Based Information Site Selection (2002)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
With the advent of the World Wide Web, a vast number of heterogenous information sources has become available. In order to access and process these data, suitable tools and methods for building an...
On computing all abductive explanations (2002)
We consider the computation of all respectively a polynomial subset of the explanations of an abductive query from a Horn theory, and pay particular attention to whether the query is a positive or...
New results on monotone dualization and generating hypergraph transversals (2002)
Thomas Eiter, Georg Gottlob, Kazuhisa Makino
ac.jp This paper considers the problem of dualizing a monotone CNF (equivalently, computing all minimal transversals of a hypergraph), whose associated decision problem is a prominent open problem in...
Hypergraph transversal computation and related problems in logic and AI (2002)
Abstract. Generating minimal transversals of a hypergraph is an important problem which has many applications in Computer Science. In the present paper, we address this problem and its decisional...
Complexity Results for Explanations in the Structural-Model Approach (2002)
Abtg Wissensbasierte Systeme, Revised Version, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
We analyze the computational complexity of Halpern and Pearl's (causal) explanations in the structural-model approach, which are based on their notions of weak and actual cause. In particular,...
Answer set planning under action costs (2002)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
Recently, planning based on answer set programming has been proposed as an approach towards realizing declarative planning systems. In this paper, we present the language K c, which extends the...
Causes and Explanations in the Structural-Model Approach: Tractable Cases (2002)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
In this paper, we continue our research on the algorithmic aspects of Halpern and Pearl's causes and explanations in the structural-model approach. To this end, we present new characterizations...
Answer set planning under action costs (2002)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
Abstract. We present §© ¨ , which extends the declarative planning language § by action costs and optimal plans that minimize overall action costs (cheapest plans). As shown, this novel language...
Answer set planning under action costs (2002)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
Abstract. We present Kc, which extends the declarative planning language Kby action costs and optimal plans that minimize overall action costs (cheapest plans). As shown, this novel language allows...
Complexity Results for Explanations in the Structural-Model Approach (2002)
Thomas Eiter, Thomas Lukasiewicz
We analyze the computational complexity of Halpern and Pearl's (causal) explanations in the structural-model approach, which are based on their notions of weak and actual causality. In...
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
In this paper, we consider an approach to update nonmonotonic knowledge bases represented as extended logic programs under the answer set semantics. In this approach, new information is incorporated...
Complexity results for explanations in the structural-model approach (2002)
We analyze the computational complexity of Halpern and Pearl’s (causal) explanations in the structural-model approach, which are based on their notions of weak and actual causality. In particular,...
Hypergraph transversal computation and related problems in logic and AI (2002)
Abstract. Generating minimal transversals of a hypergraph is an important problem which has many applications in Computer Science. In the present paper, we address this problem and its decisional...
On computing all abductive explanations (2002)
We consider the computation of all respectively a polynomial subset of the explanations of an abductive query from a Horn theory, and pay particular attention to whether the query is a positive or...
A Logic Programming Approach to Knowledge-State Planning: Semantics and Complexity (2001)
Eiter, Thomas, Faber, Wolfgang, Leone, Nicola, Pfeifer, Gerald, Polleres, Axel
We propose a new declarative planning language, called K, which is based on principles and methods of logic programming. In this language, transitions between states of knowledge can be described,...
Second-order logic over strings: Regular and nonregular fragments (2001)
Thomas Eiter, Georg Gottlob, Thomas Schwentick
Abstract. By a well-known result due to Buchi and Trakhtenbrot, all monadic second-order sentences over words describe regular languages. In this paper, we investigate prefix classes of general...
Complexity results for structure-based causality (2001)
Thomas Eiter, Thomas Lukasiewicz
We analyze the computational complexity of causal relationships in Pearl's structural models, where we focus on causality between variables, event causality, and probabilistic causality. In...
A framework for declarative update specifications in logic programs (2001)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
Recently, several approaches for updating knowledge bases represented as logic programs have been proposed. In this paper, we present a generic framework for declarative specifications of update...
Complexity results for structure-based causality (2001)
Thomas Eiter, Thomas Lukasiewicz
We analyze the computational complexity of causal relationships in Pearl's structural models, where we focus on causality between variables, event causality, and probabilistic causality. In...
A data model and algebra for probabilistic complex values (2001)
Thomas Eiter, Thomas Lukasiewicz, Michael Walter
Abstract We present a probabilistic data model for complex values. More precisely, we introduce probabilistic complex value relations, which combine the concept of probabilistic relations with the...
Computing Stable Models with Quantified Boolean Formulas: Some Experimental Results (2001)
Uwe Egly, Thomas Eiter, Volker Klotz, Hans Tompits, Stefan Woltran
Quantified boolean formulas (QBFs) are extensions of ordinary propositional formulas which admit efficient representations of many important reasoning tasks. The existence of sophisticated...
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Tu Wien, Tu Wien
Preferred and Weakly Preferred Answer Sets are extensions to Answer Set Programming (ASP) which allow the user to specify priorities for rules. In this paper we present a first implementation of...
Probabilistic Object Bases (2001)
Thomas Eiter, James J. Lu, Thomas Lukasiewicz, V. S. Subrahmanian
There are many applications where an object oriented data model is a good way of representing and querying data. However, current object database systems are unable to handle the case of objects...
Reasoning about Evolving Nonmonotonic Knowledge Bases (2001)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
this paper, we introduce a framework for reasoning about evolving knowledge bases, which are represented as extended logic programs and maintained by an update policy. We rst describe a formal model...
Thomas Eiter, Wolfgang Faber, Tu Wien
Preferred and Weakly Preferred Answer Sets are extensions to Answer Set Programming (ASP) which allow the user to specify priorities for rules. In this paper we present a first implementation of...
Thomas Eiter, Wolfgang Faber, Tu Wien
Preferred and Weakly Preferred Answer Sets are extensions to Answer Set Programming (ASP) which allow the user to specify priorities for rules. In this paper we present a first implementation of...
An Update Front-End for Extended Logic Programs (2001)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
Abstract. In recent years, several approaches for dealing with updates of logic programs have been proposed. In this paper, we describe the system upd, an implementation of the update formalism due...
Schneider: Matchmaking for Structured Objects (2001)
Thomas Eiter, Daniel Veit, Jörg P. Müller, Martin Schneider
Abstract A fundamental task in multi-agent systems is matchmaking, which is to retrieve and classify service descriptions of agents that (best) match a given service request. Several approaches to...
A framework for declarative update specifications in logic programs (2001)
Thomas Eiter, Michael Fink, Giuliana Sabbatini, Hans Tompits
Recently, several approaches for updating knowledge bases represented as logic programs have been proposed. In this paper, we present a generic framework for declarative specifications of update...
Heterogenous Active Agents (2000)
Subrahmanian, VS, Bonatti, Piero, Dix, Jurgen, Eiter, Thomas, Kraus, Sarit, Ozcan, Fatma, ...
Software agents are the latest advance in the trend toward smaller, modular pieces of code, where each module performs a well-defined, focused task or set of tasks. Programmed to interact with and...
QUIP - A Tool for Computing Nonmonotonic Reasoning Tasks (2000)
Egly, Uwe, Eiter, Thomas, Tompits, Hans, Woltran, Stefan
In this paper, we outline the prototype of an automated inference tool, called QUIP, which provides a uniform implementation for several nonmonotonic reasoning formalisms. The theoretical basis of...
DLV - A System for Declarative Problem Solving (2000)
Eiter, Thomas, Faber, Wolfgang, Koch, Christoph, Leone, Nicola, Pfeifer, Gerald
DLV is an efficient logic programming and non-monotonic reasoning (LPNMR) system with advanced knowledge representation mechanisms and interfaces to classic relational database systems. Its core...
On Updates of Logic Programs: Semantics and Properties (2000)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Giuliana Sabbatini, ...
www.kr.tuwien.ac.at
Solving advanced reasoning tasks using quantified Boolean formulas (2000)
Uwe Egly, Thomas Eiter, Hans Tompits, Stefan Woltran
We consider the compilation of different reasoning tasks into the evaluation problem of quantified boolean formulas (QBFs) as an approach to develop prototype reasoning systems useful, e.g., for...
Default reasoning from conditional knowledge bases: Complexity and tractable cases (2000)
Thomas Eiter, Thomas Lukasiewicz
Conditional knowledge bases have been proposed as belief bases that include defeasible rules (also called defaults) of the form " ! ", which informally read as "generally,...
Heterogeneous Active Agents, III: Polynomially implementable agents (2000)
Thomas Eiter, V. S. Subrahmanian
In [17], two of the authors have introduced techniques to build agents on top of arbitrary data structures, and to "agentize " new/existing programs. They provided a series of...
Prioritizing default logic (2000)
In nonmonotonic reasoning conflicts among defaults are ubiquitous. For instance, more specific rules may be in conflict with more general ones, a problem which has been studied intensively in the...
Extension of the relational algebra to probabilistic complex values (2000)
Thomas Eiter, Thomas Lukasiewicz, Michael Walter
Abstract. We present a probabilistic data model for complex values. More precisely, we introduce probabilistic complex value relations, which combine the concept of probabilistic relations with the...
On the Complexity of Theory Curbing (2000)
Abstract. In this paper, we determine the complexity of propositional theory curbing. Theory Curbing is a nonmonotonic technique of common sense reasoning that is based on model minimality but unlike...
Using the dlv system for planning and diagnostic reasoning (2000)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
dlv is a state-of-the-art system for disjunctive logic programming, which may be used as an implementation bed for solving declarative knowledge representation problems. In this paper, we review the...
Planning under incomplete knowledge (2000)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer, Axel Polleres
Abstract. We propose a new logic-based planning language, called K. Transitions between states of knowledge can be described in K, and the language is well suited for planning under incomplete...
On Updates of Logic Programs: Semantics and Properties (2000)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Michael Fink, Michael Fink, Giuliana Sabbatini, ...
www.kr.tuwien.ac.at
DLV { A System for Declarative Problem Solving (2000)
Thomas Eiter, Wolfgang Faber, Christoph Koch, Nicola Leone, Gerald Pfeifer
DLV is an ecient logic programming and nonmonotonic reasoning (LPNMR) system with advanced knowledge representation mechanisms and interfaces to classic relational database systems. Its core language...
Extension of the relational algebra to probabilistic complex values (2000)
Thomas Eiter, Thomas Lukasiewicz, Michael Walter
Abstract. We present a probabilistic data model for complex values. More precisely, we introduce probabilistic complex value relations, which combine the concept of probabilistic relations with the...
A Data Model and Algebra for Probabilistic Complex Values (2000)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz, Michael Walter, ...
. We present a probabilistic data model for complex values. More precisely, we introduce probabilistic complex value relations, which combine the concept of probabilistic relations with the idea of...
Solving advanced reasoning tasks using quantified Boolean formulas (2000)
Uwe Egly, Thomas Eiter, Hans Tompits, Stefan Woltran
We consider the compilation of different reasoning tasks into the evaluation problem of quantified boolean formulas (QBFs) as an approach to develop prototype reasoning systems useful for, e.g.,...
Probabilistic Object Bases (1999)
Eiter, Thomas, Lu, James, Lukasiewicz, Thomas, Subrahmanian, V.S.
There are many applications where an object oriented data model is a good way of representing and querying data. However, current object database systems are unable to handle the case of objects...
Probabilistic Object Bases (1999)
Eiter, Thomas, Lu, James, Lukasiewicz, Thomas, Subrahmanian, V.S.
There are many applications where an object oriented data model is a good way of representing and querying data. However, current object database systems are unable to handle the case of objects...
Computing intersections of Horn theories for reasoning with models (1999)
Thomas Eiter, Toshihide Ibaraki, Kazuhisa Makino
We consider computational issues when combining logical knowledge bases represented by their characteristic models; in particular, we study taking their logical intersection. We present efficient...
The diagnosis frontend of the dlv system (1999)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer
This paper presents the Diagnosis Frontend of dlv, which is a knowledge representation system under development at the Technische Universitat Wien. The kernel language of the system is an extension...
The diagnosis frontend of the dlv system (1999)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer
This paper presents the Diagnosis Front-End of dlv, which is a knowledge representation system under development at the Technische Universitat Wien. The kernel language of the system is an extension...
Generalized Quantifiers in Logic Programs (1999)
Abstract. Generalized quantifiers are an important concept in modeltheoretic logic which has applications in different fields such as linguistics, philosophical logic and computer science. In this...
Heterogeneous Active Agents, II: Algorithms and Complexity (1999)
Thomas Eiter, V. S. Subrahmanian
In Part I of this series of papers, we developed a language called Agent Programs for defining the operational behavior of software agents and defined a set of successively more satisfying...
Prioritizing Default Logic: Abridged Report (1999)
Abstract. A number of prioritized variants of Reiter's default logic have been described in the literature. In this paper, we introduce two natural principles for preference handling and show...
Preferred answer sets for extended logic programs (1999)
In this paper, we address the issue of how Gelfond and Lifschitz's answer set semantics for extended logic programs can be suitably modified to handle prioritized programs. In such programs an...
Preferred answer sets for extended logic programs (1999)
In this paper, we address the issue of how Gelfond and Lifschitz's answer set semantics for extended logic programs can be suitably modified to handle prioritized programs. In such programs an...
Preferred answer sets for extended logic programs (1999)
In this paper, we extend Gelfond and Lifschitz 's answer set semantics to prioritized extended logic programs. In such programs, an ordering on the program rules is used to express preferences....
Expressive Power and Complexity of Partial Models for Disjunctive Deductive Databases (1999)
This paper investigates the expressive power and complexity of partial model semantics for disjunctive deductive databases. In particular,...
Enhancing Model Checking in Verification by AI Techniques (1999)
Francesco Buccafurri, Thomas Eiter, Georg Gottlob, Nicola Leone
Model checking is a fruitful application of computational logic with high relevance to the verification of concurrent systems. While model checking is capable of automatically testing that a...
Complexity Results for Default Reasoning from Conditional Knowledge Bases (1999)
Thomas Eiter, Thomas Lukasiewicz
Conditional knowledge bases have been proposed as belief bases that include defeasible rules (also called defaults) of the form " ! ", which informally read as "generally, if then...
Complexity Results for Default Reasoning from Conditional Knowledge. . . (1999)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz
. Conditional knowledge bases have been proposed as belief bases that include defeasible rules (also called defaults) of the form " ! ", which informally read as "generally, if then...
Probabilistic Object Bases (1999)
Abtg Wissensbasierte Systeme, Thomas Eiter, Thomas Lukasiewicz, Thomas Lukasiewicz, James J. Lu, ...
. There are many applications where an object oriented data model is a good way of representing and querying data. However, current object database systems are unable to handle the case of objects...
Heterogeneous Active Agents, III: Polynomially Implementable Agents (1999)
Abtg Wissensbasierte Systeme, T. J. Rogers, Thomas Eiter, Thomas Eiter, V. S. Subrahmanian, V. S. Subrahmanian
. In (Eiter, Subrahmanian, and Pick 1999), the authors have introduced techniques to build agents on top of arbitrary data structures, and to "agentize" new/existing programs. They provided...
Preferred Answer Sets for Extended Logic Programs (1999)
Abtg Wissensbasierte Systeme, Gerd Brewka, Gerhard Brewka, Thomas Eiter, Thomas Eiter
. In this paper, we address the issue of how Gelfond and Lifschitz's answer set semantics for extended logic programs can be suitably modified to handle prioritized programs. In such programs an...
Disjunction of Horn theories and their cores (1999)
Abtg Wissensbasierte Systeme, Kazuhisa Makino, Thomas Eiter, Thomas Eiter, Toshihide Ibaraki, Toshihide Ibaraki
. In this paper, we study issues on disjunctions of propositional Horn theories. In particular, we consider deciding whether a disjunction of Horn theories is Horn, and, if not, computing a Horn core...
Complexity and Expressive Power of Logic Programming (1999)
Abtg Wissensbasierte Systeme, Georg Gottlob, Andrei Voronkov, Evgeny Dantsin, Evgeny Dantsin, Thomas Eiter, ...
. This paper surveys various complexity and expressiveness results on different forms of logic programming. The main focus is on decidable forms of logic programming, in particular, propositional...
Preferred answer sets for extended logic programs (1998)
In this paper, we address the issue of how Gelfond and Lifschitz's answer set semantics for extended logic programs can be suitably modified to handle prioritized programs. In such programs an...
A first-order representation of stable models (1998)
Lu, James, Eiter, Thomas, Subrahmanian, V.S
Turi (1991) introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained...
Decision lists and related Boolean functions (1998)
Ibaraki, Toshihide, Eiter, Thomas, Makino, Kazuhisa
We consider Boolean functions represented by decision lists, and study their relationships to other classes of Boolean functions. It turns out that the elementary class of 1decision lists has...
Heterogeneous active agents (1998)
Pick, George, Subrahmanian, V.S, Eiter, Thomas
Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various situations...
Computing intersections of Horn theories for reasoning with models (1998)
Ibaraki, Toshihide, Eiter, Thomas, Makino, Kazuhisa
Modelbased reasoning has been proposed as an alternative form of representing and accessing logical knowledge bases. In this approach, a knowledge base is represented by a set of characteristic...
Existential second-order logic over strings (1998)
Gurevich, Yuri, Gottlob, Georg, Eiter, Thomas
Existential secondorder logic (ESO) and monadic secondorder logic (MSO) have attracted much interest in logic and computer science. ESO is a much more expressive logic over word structures than...
Enhancing symbolic model checking by AI techniques (1998)
Leone, Nicola, Gottlob, Georg, Eiter, Thomas, Buccafurri, Francesco
Comparisons of different cellular devices and the investigation of their computing power can be made in terms of their capabilities to timeconstruct and timecompute functions. Timeconstruction...
Heterogeneous Active Agents (1998)
Subrahmanian, V.S., Eiter, Thomas, Pick, George
Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various situations...
Heterogeneous Active Agents (1998)
Subrahmanian, V.S., Eiter, Thomas, Pick, George
Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various situations...
Heterogeneous active agents (1998)
Eiter, Thomas, Subrahmanian, V.S, Pick, George
Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various situations...
Computing intersections of Horn theories for reasoning with models (1998)
Eiter, Thomas, Ibaraki, Toshihide, Makino, Kazuhisa
Modelbased reasoning has been proposed as an alternative form of representing and accessing logical knowledge bases. In this approach, a knowledge base is represented by a set of characteristic...
Decision lists and related Boolean functions (1998)
Eiter, Thomas, Ibaraki, Toshihide, Makino, Kazuhisa
We consider Boolean functions represented by decision lists, and study their relationships to other classes of Boolean functions. It turns out that the elementary class of 1decision lists has...
A first-order representation of stable models (1998)
Eiter, Thomas, Lu, James, Subrahmanian, V.S
Turi (1991) introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained...
Preferred answer sets for extended logic programs (1998)
In this paper, we address the issue of how Gelfond and Lifschitz's answer set semantics for extended logic programs can be suitably modified to handle prioritized programs. In such programs an...
The KR System dlv: Progress Report, Comparisons and Benchmarks (1998)
Thomas Eiter, Nicola Leone, Cristinel Mateis, Gerald Pfeifer, Tu Wien, Tu Wien, ...
Universit`a della Calabria
A First-Order Representation of Stable Models (1998)
Thomas Eiter, James Lu, V. S. Subrahmanian
Turi (1991) introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained...
Deontic Action Programs (1998)
Thomas Eiter, V. S. Subrahmanian
Abstract: We introduce the concept of an Action Policy in the context of databases. Intuitively, such a policy tells us which from a collection of actions must be executed (i.e. are obligatory),...
Expressive Power and Complexity of Partial Models for Disjunctive Deductive Databases (1998)
Eiter Leone Sacc, Thomas Eiter, Nicola Leone, T. Eiter, N. Leone
This paper investigates the expressive power and complexity of partial model semantics for disjunctive deductive databases. In particular, partial stable, regular model, maximal stable (M-stable),...
Preferred Answer Sets for Extended Logic Programs (1998)
Gerd Brewka, Gerhard Brewka, Thomas Eiter, Thomas Eiter
. In this paper, we address the issue of how Gelfond and Lifschitz's answer set semantics for extended logic programs can be suitably modified to handle prioritized programs. In such programs an...
Heterogeneous Active Agents (1998)
Thomas Eiter, V. S. Subrahmanian
Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various situations...
The Diagnosis Frontend of the dlv System (1998)
Thomas Eiter, Wolfgang Faber, Nicola Leone, Gerald Pfeifer
This paper presents the Diagnosis Front-End of dlv, which is a knowledge representation system under development at the Technische Universitat Wien. The kernel language of the system is an extension...
Heterogeneous Active Agents (1998)
George Pick, Thomas Eiter, Thomas Eiter, V. S. Subrahmanian, V. S. Subrahmanian
.Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various...
First-Order Representation of Stable Models (1998)
Thomas Eiter, Thomas Eiter, James Lu, James Lu, V. S. Subrahmanian, V. S. Subrahmanian
Turi (1991) introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained...
Decision Lists and Related Boolean Functions (1998)
Thomas Eiter, Thomas Eiter, Toshihide Ibaraki, Toshihide Ibaraki, Kazuhisa Makino, Kazuhisa Makino
. We consider Boolean functions represented by decision lists, and study their relationships to other classes of Boolean functions. It turns out that the elementary class of 1-decision lists has...
The KR System dlv: Progress Report, Comparisons and Benchmarks (1998)
Thomas Eiter, Nicola Leone, Cristinel Mateis, Gerald Pfeifer, Tu Wien, Tu Wien, ...
dlv is a knowledge representation system, based on disjunctive logic programming, which offers frontends to several advanced KR formalisms. The system has been developed since one year at the...
Computing Intersections Of Theories For Reasoning With Models (1998)
Thomas Eiter, Thomas Eiter, Toshihide Ibaraki, Toshihide Ibaraki, Kazuhisa Makino, Kazuhisa Makino
. Model-based reasoning has been proposed as an alternative form of representing and accessing logical knowledge bases. In this approach, a knowledge base is represented by a set of characteristic...
Progress Report on the Disjunctive Deductive Database System (1998)
Thomas Eiter, Nicola Leone, Cristinel Mateis, Gerald Pfeifer, Francesco Scarcello
. dlv is a deductive database system, based on disjunctive logic programming, which offers front-ends to several advanced KR formalisms. The system has been developed since the end of 1996 at...
Preferred Answer Sets for Extended Logic Programs (1998)
In this paper, we extend Gelfond and Lifschitz's answer set semantics to prioritized extended logic programs. In such programs, an ordering on the program rules is used to express preferences....
A First-Order Representation of Stable Models (1998)
Thomas Eiter, James Lu, V. S. Subrahmanian
Turi (1991) introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained...
Decision lists and related boolean functions (1998)
Thomas Eiter, Thomas Eiter, Toshihide Ibaraki, Toshihide Ibaraki, Kazuhisa Makino, Kazuhisa Makino
Abstract. We consider Boolean functions represented by decision lists, and study their relationships to other classes of Boolean functions. It turns out that the elementary class of 1-decision lists...
Enhancing symbolic model checking by AI techniques (1997)
Buccafurri, Francesco, Eiter, Thomas, Gottlob, Georg, Leone, Nicola
Comparisons of different cellular devices and the investigation of their computing power can be made in terms of their capabilities to timeconstruct and timecompute functions. Timeconstruction...
Existential second-order logic over strings (1997)
Eiter, Thomas, Gottlob, Georg, Gurevich, Yuri
Existential secondorder logic (ESO) and monadic secondorder logic (MSO) have attracted much interest in logic and computer science. ESO is a much more expressive logic over word structures than...
Modular logic programming and generalized quantifiers (1997)
Thomas Eiter, Georg Gottlob, Ag Informatik
Abstract. The research on systems of logic programming with modules has followed two mainstreams, programming-in-the-large, where compositional operators are provided for combining separate and...
Computing Non-Ground Representations of Stable Models (1997)
Thomas Eiter, James Lu, V. S. Subrahmanian
Abstract. Turi [20] introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained...
Modular logic programming and generalized quantifiers (1997)
Helmut Veith, Thomas Eiter, Thomas Eiter, Georg Gottlob, Georg Gottlob
The research on logic programming with modules has followed two mainstreams: Programming-in-the-large, where compositional operators are provided for combining separate and independent modules, and...
On the indiscernibility of individuals in logic programming (1997)
Thomas Eiter, Georg Gottlob, Nicola Leone
According to Leibniz ' principle, two individuals a and b are indiscernible, if they share the same properties. Indiscernibility of objects provides a potential for optimization in deductive...
On the Partial Semantics for Disjunctive Deductive Databases (1997)
Thomas Eiter, Nicola Leone, T. Eiter, N. Leone
preliminary report Partial stable models for deductive databases, i.e., normal function-free logic programs (also called datalog programs), have two equivalent denitions: one based on 3-valued logics...
We consider disjunctive Datalog, a powerful database query language based on disjunctive gic programming. Briefly, disjunctive Datalog is a variant of Datalog where disjunctions may appear in the...
Abduction from logic programs: Semantics and complexity (1997)
Thomas Eiter, Georg Gottlob, Nicola Leone
Abduction-- from observations and a theory, find using hypotheses an explanation for the observations-- gained increasing interest during the last years. This form of reasoning has wide applicability...
The dlv system: Model generator and application frontends (1997)
Simona Citrigno, Thomas Eiter, Wolfgang Faber, Georg Gottlob, Christoph Koch, Nicola Leone, ...
ay
Semantics and Complexity of Abduction from Default Theories (1997)
Thomas Eiter, Georg Gottlob, Nicola Leone
Abductive reasoning (roughly speaking, find an explanation for observations out of hypotheses), has been recognized as an important principle of common-sense reasoning. Since logical knowledge...
Default Logic as a Query Language (1997)
Marco Cadoli, Thomas Eiter, Georg Gottlob
| Research in non-monotonic reasoning has focused largely on the idea of representing knowledge about the world via rules that are generally true but can be defeated. Even if relational databases are...
Semantics and Complexity of Abduction from Default Theories (Extended Abstract) (1997)
Thomas Eiter, Georg Gottlob, Nicola Leone
Since logical knowledge representation is commonly based on nonclassical formalisms like default logic, autoepistemic logic, or circumscription, it is necessary to perform abductive reasoning from...
Default Logic as a Query Language (1997)
Marco Cadoli, Thomas Eiter, Georg Gottlob
Research in NMR has focused largely on the idea of representing knowledge about the world via rules that are generally true but can be defeated. Even if relational databases are nowadays the main...
Existential Second-Order Logic over Strings (1997)
Thomas Eiter, Thomas Eiter, Georg Gottlob, Georg Gottlob, Yuri Gurevich, Yuri Gurevich
. Existential second-order logic (ESO) and monadic second-order logic (MSO) have attracted much interest in logic and computer science. ESO is a much more expressive logic over word structures than...
Distance Measures for Point Sets and Their Computation (1997)
We consider the problem of measuring the similarity or distance between two finite sets of points in a metric space, and computing the measure. This problem has applications in, e.g., computational...
Enhancing Symbolic Model Checking by AI Techniques (1997)
Nicola Leone, Francesco Buccafurri, Francesco Buccafurri, Georg Gottlob, Georg Gottlob, Thomas Eiter, ...
. Model checking is a fruitful application of computational logic with high relevance to the verification of concurrent systems. While model checking is capable of automatically testing that a...
System: Model Generator and Application Frontends (1997)
Simona Citrigno, Thomas Eiter, Wolfgang Faber, Georg Gottlob, Christoph Koch, Nicola Leone, ...
During the last years, much research has been done concerning semantics and complexity of Disjunctive Deductive Databases (DDDBs). While DDDBs --- function-free disjunctive logic programs with...
The dlv System: Model Generator and Application Frontends (1997)
Simona Citrigno Thomas, Thomas Eiter, Wolfgang Faber, Georg Gottlob, Christoph Koch, Nicola Leone, ...
During the last years, much research has been done concerning semantics and complexity of Disjunctive Deductive Databases (DDDBs). While DDDBs | function-free disjunctive logic programs with negation...
Annals of Pure and AppliedLogic, 78 (1996), 111--125. (1997)
Normal Forms For, Thomas Eiter, Georg Gottlob, Yuri Gurevich
We start with a simple proof of Leivant's normal form theorem for \Sigma 1 formulas over finite successor structures. Then we use that normal form to prove the following: (i) over all finite...
Existential Second-Order Logic over Strings (Extended Abstract) (1997)
Thomas Eiter, Georg Gottlob, Yuri Gurevich, G. Gottlob, Y. Gurevich
Existential second-order logic (ESO) and monadic second-order logic (MSO) have attracted much interest in logic and computer science. ESO is a much moreexpressive logic over word structures than MSO....
The Architecture of a Disjunctive Deductive Database System (1997)
Thomas Eiter, Nicola Leone, Cristinel Mateis, Gerald Pfeifer, Francesco Scarcello, Ag Informatik, ...
Disjunctive Deductive Databases (DDDBs) --- function-free disjunctive logic programs with negation in rule bodies allowed --- have been recently recognized as a powerful tool for knowledge...
A Deductive System for Non-Monotonic Reasoning (1997)
Thomas Eiter, Nicola Leone, Cristinel Mateis, Gerald Pfeifer, Francesco Scarcello
. Disjunctive Deductive Databases (DDDBs) --- function-free disjunctive logic programs with negation in rule bodies allowed --- have been recently recognized as a powerful tool for knowledge...
Computing Non-Ground Representations of Stable Models (1997)
Thomas Eiter, James Lu, V. S. Subrahmanian, Ag Informatik
Abstract. Turi [20] introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained...
On the Indiscernibility of Individuals in Logic Programming (1997)
EITER, THOMAS, GOTTLOB, GEORG, LEONE, NICOLA
According to Leibniz' principle, two individuals a and b are indiscernible, if they share the same properties. Indiscernibility of objects provides a potential for optimization in deductive systems,...
Querying disjunctive databases through nonmonotonic logics (1996)
Piero A. Bonatti, Thomas Eiter
Query languages for retrieving information from disjunctive databases are an interesting open area of research. In this paper we study the expressive power of major non-monotonic formalisms-- such as...
Thomas Eiter Georg, Thomas Eiter, Georg Gottlob, Georg Gottlob, Yuri Gurevich, Yuri Gurevich
We start with a simple proof of Leivant's normal form theorem for \Sigma 1 1 formulas over finite successor structures. Then we use that normal form to prove the following: (i) over all finite...
Thomas Eiter, Georg Gottlob, Yuri Gurevich
We start with a simple proof of Leivant's normal form theorem for 1 1 formulas over nite successor structures. Then we use that normal form to prove the following: (i) over all nite structures,...
Querying Disjunctive Databases Through Nonmonotonic Logics (1996)
Piero A. Bonatti, Thomas Eiter
Query languages for retrieving information from disjunctive databases are an interesting open area of research. In this paper we study the expressive power of major non-monotonic formalisms { such as...
Thomas Eiter, Georg Gottlob, Yuri Gurevich
We start with a simple proof of Leivant's normal form theorem for \Sigma 1 1 formulas over finite successor structures. Then we use that normal form to prove the following: (i) over all finite...
On the Indiscernibility of Individuals in Logic Programming (1996)
Thomas Eiter, Thomas Eiter, Georg Gottlob, Georg Gottlob, Nicola Leone, Nicola Leone
According to Leibniz's principle, two individuals a and b are indiscernible, if they share the same properties. Indiscernibility of objects provides a potential for optimization in deductive...
Thomas Eiter, Georg Gottlob, Yuri Gurevich
We start with a simple proof of Leivant's normal form theorem for \Sigma 1 1 formulas over finite successor structures. Then we use that normal form to prove the following: (i) over all finite...
Mannila: Recognizing renamable generalized propositional Horn formulas is NP-complete (1995)
Yamasaki and Doshita have dened an extension of the class of propositional Horn formulas; later, Gallo and Scutella generalized this class to a hierarchy 0 1 : : : k : ::, where 0 is the set of Horn...
Identifying the minimal transversals of a hypergraph and related problems (1995)
The paper considers two decision problems on hypergraphs, hypergraph saturation and recognition of the transversal hypergraph, and discusses their significance for several search problems in applied...
Note on the Complexity of Some Eigenvector Problems (1995)
Thomas Eiter, Thomas Eiter, Georg Gottlob, Georg Gottlob
We consider the computation of eigenvectors x = (x 1 ; : : : ; n) over the integers, where each component x i satisfies jx i j c for a constant c. We address decisional problems in this context, and...
Identifying the Minimal Transversals of a Hypergraph and Related Problems (1995)
The paper considers two decision problems on hypergraphs, hypergraph saturation and recognition of the transversal hypergraph, and discusses their significance for several search problems in applied...
Thomas Eiter, Georg Gottlob, Yuri Gurevich
We start with a simple proof of Leivant's normal form theorem for \Sigma 1 1 formulas over finite successor structures. Then we use that normal form to prove the following: (i) over all finite...
The complexity of logic-based abduction (1995)
Abduction is an important form of nonmonotonic reasoning allowing one to find explanations for certain symptoms or manifestations. When the application domain is described by a logical theory, we...
Mannila: Recognizing renamable generalized propositional Horn formulas is NP-complete (1995)
Thomas Eiter, Pekka Kilpeläinen, Heikki Mannila
Yamasaki and Doshita have defined an extension of the class of propositional Horn formulas; later, Gallo and Scutellà generalized this class to a hierarchy Γ0 ⊆ Γ1 ⊆... ⊆ Γk ⊆..., where...
Exact Transversal Hypergraphs and Application to Boolean µ-Functions (1994)
Call an hypergraph, that is a family of subsets (edges) from a nite vertex set, an exact transversal hypergraph i each of its minimal transversals, i.e., minimal vertex subsets that intersect each...
Adding Disjunction to Datalog (Extended Abstract) (1994)
Thomas Eiter, Georg Gottlob, Heikki Mannila
) Thomas Eiter Georg Gottlob Heikki Mannila Christian Doppler Laboratory for Expert Systems, Information Systems Department Technical University of Vienna, Paniglgasse 16, A-1040 Wien, Austria...
Computing Discrete Fréchet Distance (1994)
Thomas Eiter, Thomas Eiter, Heikki Mannila, Heikki Mannila
The Frechet distance between two curves in a metric space is a measure of the similarity between the curves. We present a discrete variation of this measure.
Exact Transversal Hypergraphs and Application to Boolean µ-Functions (1994)
Call an hypergraph, that is a family of subsets (edges) from a finite vertex set, an exact transversal hypergraph iff each of its minimal transversals, i.e., minimal vertex subsets that intersect...
Propositional Circumscription and Extended Closed World Reasoning are \Pi P 2 -complete (1993)
Circumscription and the closed world assumption with its variants are well-known nonmonotonic techniques for reasoning with incomplete knowledge. Their complexity in the propositional case has been...
Complexity Aspects of Various Semantics for Disjunctive Databases (1993)
This paper addresses complexity issues for important problems arising with disjunctive databases. In particular, the complexity of inference of a literal and a formula from a propositional...
Complexity Results for Disjunctive Logic Programming and Application to Nonmonotonic Logics (1993)
Ben-Eliyahu and Dechter have shown that stable semantics of a large class of extended propositional disjunctive logic programs (EDLPs) can be efficiently expressed in the language of propositional...
The Complexity of Nested Counterfactuals and Iterated Knowledge Base Revisions (1993)
We consider the computational complexity of evaluating nested counterfactuals over a propositional knowledge base. Counterfactual implication p ? q models a statement "if p, then q," where...
The Complexity of Logic-Based Abduction (1993)
Thomas Eiter, Thomas Eiter, Georg Gottlob, Georg Gottlob
Abduction is an important form of nonmonotonic reasoning allowing one to find explanations for certain symptoms or manifestations. When the application domain is described by a logical theory, we...
The Complexity of Nested Counterfactuals and Iterated Knowledge Base Revisions (1993)
We consider the computational complexity of evaluating nested counterfactuals over a propositional knowledge base. A counterfactual p ? q is a conditional query with the meaning "If p would be...
Thomas Eiter, Georg Gottlob, Yuri Gurevich
We introduce curbing, a new nonmonotonic technique of commonsense reasoning that is based on model minimality but unlike circumscription treats disjunction inclusively. A finitely axiomatized...
Thomas Eiter, Georg Gottlob, Yuri Gurevich
We introduce curbing, a new nonmonotonic technique of commonsense reasoning that is based on model minimality but unlike circumscription treats disjunction inclusively. A first-order theory T is...
Circumscriptive Approach For, Thomas Eiter, Georg Gottlob, Yuri Gurevich
Weintroduce curbing, a new nonmonotonic technique of commonsense reasoning that is based on model minimality but unlike circumscription treats disjunction inclusively. A first-order theory T is...
A circumscriptive approach for inclusive interpretation of disjunctive information*
On the Complexity of Propositional Knowledge Base Revision, Updates, and Counterfactuals (1992)
Thomas Eiter, Georg Gottlob, Expert Systems
We study the complexity of several recently proposed methods for updating or revising propositional knowledge bases. In particular, we derive complexity results for the following problem: given a...
On the Complexity of Propositional Knowledge Base Revision, Updates, and Counterfactuals (1992)
We study the complexity of several recently proposed methods for updating or revising propositional knowledge bases under the principle of minimal change. In particular, we derive complexity results...
An Efficient Method for Eliminating Varying Predicates from a Circumscription (1992)
Marco Cadoli, Thomas Eiter, Georg Gottlob
Circumscription appears to be the most powerful and well-studied technique used in formalizing common-sense reasoning. The general form of predicate circumscription allows for fixed and varying...
On computing all abductive explanations (preliminary report (1988)
Abtg Wissensbasierte Systeme, Kazuhisa Makino, Thomas Eiter, Thomas Eiter
1 and Kazuhisa Makino 2 Abstract. We consider the computation of all respectively a polynomial subset of the explanations of an abductive query from a Horn theory, and pay particular attention to...